Speckle interferometric observations of the collision of comet Shoemaker-Levy 9 with Jupite

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常用色谱术语（中英文对照）

常用色谱术语（中英文对照）色谱图 chromatogram色谱峰chromatographicpeak峰底peak base峰高h，peak height峰宽W，peak width半高峰宽Wh/2，peak width athalf height 峰面积A，peak area拖尾峰tailing area前伸峰leading area假峰ghost peak畸峰distorted peak反峰negative peak拐点inflection point原点origin斑点spot区带zone复班multiple spot区带脱尾zone tailing基线base line基线漂移baseline drift基线噪声N，base line noise统计矩moment一阶原点矩γ1，first origin moment二阶中心矩μ2，second central moment三阶中心矩μ3，third central moment液相色谱法liquidchromatography，LC液液色谱法liquid liquidchromatography，LLC液固色谱法liquid solidchromatography，LSC正相液相色谱法normal phaseliquid chromatography反相液相色谱法reversed phaseliquid chromatography，RPLC 柱液相色谱法liquid columnchromatography高效液相色谱法high performanceliquid chromatography，HPLC尺寸排除色谱法size exclusionchromatography，SEC凝胶过滤色谱法gel filtrationchromatography凝胶渗透色谱法gel permeationchromatography，GPC亲和色谱法affinitychromatography离子交换色谱法ion exchangechromatography，IEC离子色谱法ionchromatography离子抑制色谱法ion suppressionchromatography离子对色谱法ion pairchromatography疏水作用色谱法hydrophobicinteraction chromatography制备液相色谱法preparativeliquid chromatography平面色谱法 planarchromatography纸色谱法 paperchromatography薄层色谱法 thin layerchromatography，TLC高效薄层色谱法 highperformance thin layerchromatography，HPTLC浸渍薄层色谱法 impregnatedthin layer chromatography凝胶薄层色谱法 gel thin layerchromatography离子交换薄层色谱法 ion exchangethin layer chromatography 制备薄层色谱法 preparativethin layer chromatography薄层棒色谱法 thin layer rodchromatography液相色谱仪 liquidchromatograph制备液相色谱仪preparativeliquid chromatograph 凝胶渗透色谱仪 gel permeationchromatograph涂布器 spreader点样器 sampleapplicator色谱柱 chromatographiccolumn棒状色谱柱 monolith columnmonolith column 微粒柱 microparticlecolumn填充毛细管柱 packedcapillary column空心柱 open tubularcolumn微径柱 microborecolumn混合柱 mixed column组合柱 coupled column预柱 precolumn保护柱 guard column预饱和柱 presaturationcolumn浓缩柱 concentratingcolumn抑制柱 suppressioncolumn薄层板 thin layerplate浓缩区薄层板 concentratingthin layer plate荧光薄层板 fluorescencethin layer plate反相薄层板reversed phasethin layer plate梯度薄层板 gradient thinlayer plate烧结板 sintered plate展开室 developmentchamber往复泵 reciprocatingpump注射泵 syringe pump气动泵 pneumatic pump蠕动泵 peristalticpump检测器 detector微分检测器 differentialdetector积分检测器 integraldetector总体性能检测器 bulk propertydetector溶质性能检测器 solute propertydetector(示差)折光率检测器 [differential] refractive indexdetector 荧光检测器 fluorescencedetector紫外可见光检测器 ultravioletvisible detector电化学检测器 electrochemicaldetector蒸发(激光)光散射检测器 [laser] light scattering detector光密度计 densitometer薄层扫描仪 thin layer scanner柱后反应器 post-columnreactor体积标记器 volume marker记录器 recorder积分仪 integrator馏分收集器 fractioncollector工作站 work station固定相 stationaryphase固定液 stationaryliquid载体 support柱填充剂 column packing化学键合相填充剂 chemicallybonded phase packing薄壳型填充剂 pellicularpacking多孔型填充剂 porous packing吸附剂 adsorbent离子交换剂 ion exchanger基体 matrix载板 support plate粘合剂 binder流动相 mobile phase洗脱(淋洗)剂 eluant，eluent展开剂 developer等水容剂 isohydricsolvent改性剂 modifier显色剂 color[developing] agent死时间 t0，dead time保留时间 tR，retentiontime调整保留时间 t''R，adjustedretention time死体积 V0，dead volume保留体积 vR，retentionvolume调整保留体积 v''R，adjustedretention volume柱外体积 Vext，extra-columnvolune粒间体积 V0，interstitialvolume(多孔填充剂的)孔体积 VP，pore volume of porous packing 液相总体积 Vtol，total liquidvolume洗脱体积 ve，elutionvolume流体力学体积 vh，hydrodynamicvolume相对保留值 ri.s，relativeretention value分离因子α，separation factor流动相迁移距离 dm，mobile phase migration distance流动相前沿 mobile phasefront溶质迁移距离 ds，solute migration distance比移值 Rf，Rf value高比移值 hRf，high Rf value相对比移值 Ri.s，relative Rfvalue保留常数值 Rm，Rm value板效能 plateefficiency折合板高 hr，reduced plate height分离度 R，resolution液相载荷量 liquid phaseloading离子交换容量 ion exchangecapacity负载容量 loadingcapacity渗透极限 permeabilitylimit排除极限 Vh，max，exclusion limit拖尾因子 T，tailing factor柱外效应 extra-columneffect管壁效应 wall effect间隔臂效应 spacer armeffect边缘效应 edge effect斑点定位法 localization ofspot放射自显影法 autoradiography原位定量 in situquantitation生物自显影法 bioautography归一法 normalizationmethod内标法 internalstandard method外标法 external standardmethod叠加法 addition method普适校准(曲线、函数)calibration function or curve[function] 谱带扩展(加宽) band broadening(分离作用的)校准函数或校准曲线 universalCalibration function or curve [of separation]加宽校正 broadeningcorrection加宽校正因子 broadeningcorrection factor溶剂强度参数ε0，solvent strength parameter洗脱序列 eluotropicseries洗脱(淋洗) elution等度洗脱 gradientelution梯度洗脱 gradientelution(再)循环洗脱 recycling elution线性溶剂强度洗脱 linear solventstrength gradient 程序溶剂 programmedsolvent程序压力 programmedpressure程序流速 programmed flow展开 development上行展开 ascendingdevelopment下行展开 descendingdevelopment双向展开 two dimensionaldevelopment环形展开 circulardevelopment离心展开 centrifugaldevelopment向心展开 centripetaldevelopment径向展开 radialdevelopment多次展开 multipledevelopment分步展开 stepwisedevelopment连续展开 continuousdevelopment梯度展开 gradientdevelopment匀浆填充 slurry packing停流进样 stop-flowinjection阀进样 valve injection柱上富集 on-columnenrichment流出液 eluate柱上检测 on-columndetection 柱寿命 column life柱流失 column bleeding显谱 visualization活化 activation反冲 back flushing脱气 degassing沟流 channeling过载 overloading(文章来源：网络)。

2024年全国统一高考英语试卷(新课标Ⅰ卷)含答案

2024年普通高等学校招生全国统一考试（新课标Ⅰ卷）英语（适用省份：福建、湖南、湖北、河北、广东、山东、江苏、江西、河南、安徽）第一部分听力（共两节，满分30分）第一节（共5小题；每小题1.5分，满分7.5分）听下面5段对话，每段对话后有一个小题，从题中所给的A、B、C三个选项中选出最佳选项，听完每段对话后，你都有10秒钟的时间来回答有关小题和阅读下一小题。

每段对话仅读一遍。

例：How much is the shirt？A. £19. 15.B. £9. 18.C. £9. 15.答案是C。

1. What is Kate doing？A. Boarding a flight.B. Arranging a trip.C. Seeing a friend off.2. What are the speakers talking about？A. A pop star.B. An old song.C. A radio program.3. What will the speakers do today？A. Go to an art show.B. Meet the man's aunt.C. Eat out with Mark.4. What does the man want to do？A. Cancel an order.B. Ask for a receipt.C. Reschedule a delivery.5. When will the next train to Bedford leave？A. At 9：45.B. At 10：15.C. At 11：00.第二节（共15小题；每小题1.5分，满分22.5分）听下面5段对话或独白。

每段对话或独白后有几个小题，从题中所给的A、B、C三个选项中选出最佳选项。

听每段对话或独白前，你将有时间阅读各个小题，每小题5秒钟；听完后，各小题将给出5秒钟的作答时间。

特性结构表面

The role of natural and synthetic zeolites as feed additives on the prevention and/or the treatment of certain farmanimal diseases:A reviewD.Papaioannou,P.D.Katsoulos,N.Panousis *,H.KaratziasClinic of Productive Animal Medicine,School of Veterinary Medicine,Aristotle University of Thessaloniki,54124Thessaloniki,GreeceReceived 4April 2005;received in revised form 12May 2005;accepted 12May 2005Available online 28June 2005AbstractThe present review comments on the role of the use of zeolites as feed additives on the prevention and/or the treatment of certain farm animal diseases.Both natural and synthetic zeolites have been used in animal nutrition mainly to improve performance traits and,based on their fundamental physicochemical properties,they were also tested and found to be eﬃcacious in the prevention of ammonia and heavy metal toxicities,poisonings as well as radioactive elements uptake and metabolic skeletal defects.During the last decade,their utilization as mycotoxin-binding adsorbents has been a topic of considerable interest and many published research data indicate their potential eﬃcacy against diﬀerent types of mycotoxins either as a primary material or after speciﬁc modiﬁcations related to their surface properties.Ingested zeolites are involved in many biochemical processes through ion exchange,adsorption and catalysis.Recent ﬁndings support their role in the prevention of certain metabolic diseases in dairy cows,as well as their shifting eﬀect on nitrogen excretion from urine to faeces in monogastric animals,which results in lower aerial ammonia concentration in the conﬁnement facilities.Moreover,new evidence provide insights into potential mechanisms involved in zeolites supporting eﬀect on animals suﬀered from gastrointestinal disturbances,including intestinal parasite infections.All the proposed mechanisms of zeolites Õeﬀects are summarized in the present review and possible focus topics for further research in selected areas are suggested.Ó2005Elsevier Inc.All rights reserved.Keywords:Zeolites;Animal health;Prevention;Treatment1.IntroductionZeolites are crystalline,hydrated aluminosilicates of alkali and alkaline earth cations,consisting of three-dimensional frameworks of SiO 4À4and AlO 5À4tetrahedra linked through the shared oxygen atoms.Both natural and synthetic zeolites are porous materials,character-ized by the ability to lose and gain water reversibly,to adsorb molecules of appropriate cross-sectional diame-ter (adsorption property,or acting as molecular sieves)and to exchange their constituent cations without majorchange of their structure (ion-exchange property)[1,2].The exploitation of these properties underlies the use of zeolites in a wide range of industrial and agricultural applications and particularly in animal nutrition since mid-1960s [3].Many researchers have proved that the dietary inclu-sion of zeolites improves average daily gain and/or feed conversion in pigs [1,4–13],calves [1,7],sheep [7,14–16],and broilers [17–19].Zeolites also enhance the reproduc-tive performance of sows [1,20,21],increase the milk yield of dairy cows [22,23]and the egg production of laying hens [24,25]and have beneﬁcial eﬀects on egg weight and the interior egg characteristics [24–26].How-ever,the extent of performance enhancement eﬀects is related to the type of the used zeolite,its purity and1387-1811/$-see front matter Ó2005Elsevier Inc.All rights reserved.doi:10.1016/j.micromeso.2005.05.030*Corresponding author.Tel.:+302310994501;fax:+302310994550.E-mail address:panousis@vet.auth.gr (N.Panousis)./locate/micromesoMicroporous and Mesoporous Materials 84(2005)161–170physicochemical properties,as well as to the supplemen-tation level used in the diets.Besides,the particle size of the zeolitic material,crystallite size and the degree of aggregation,as well as the porosity of individual parti-cles determine the access of ingestaﬂuids to the zeolitic surface during passage across gastrointestinal tract and strongly aﬀect its ion exchange,adsorption and catalytic properties.Table1summarizes the possible mechanisms by which zeolites may exert their performance promot-ing properties in farm animals.Apart from the positive eﬀects on animalsÕperfor-mance,dietary supplementation of zeolites appears to represent an eﬃcacious,complementary,supportive strategy in the prevention of certain diseases and the improvement of animalsÕhealth status.The aim of the present review article is to address the data concerning the inﬂuence of the in-feed inclusion of natural and syn-thetic zeolites on certain diseases of farm animals,to summarize the proposed mechanisms of zeolitesÕeﬀects and to suggest possible focus topics for further research in selected areas.2.Ameliorative eﬀect on the consequences of mycotoxicosesIn the recent years,high incidence rates of contami-nation of cereal grains and animal feed with mycotoxins are reported worldwide[38].One of the latest ap-proaches to this global concern has been the use of nutritionally inert adsorbents in the diet that sequester mycotoxins,thus reducing intestinal absorption and, additionally,avoiding toxic eﬀects for livestock and the carry-over of toxin compounds to animal products. For this purpose,phyllosilicates such as hydrated sodium calcium aluminosilicates(HSCAS)and benton-ite––which consist of layered crystalline structures and possess similar physicochemical properties with zeo-lites––have beenﬁrst used successfully in poultry,pig, sheep,cattle and laboratory animals[33,34,39–47].Apart from phyllosilicates,the use of zeolites has shown,lately,very promising results as well.In general, adsorption process on binders is strongly related to charge distribution,pore dimensions and accessible sur-face area of the adsorbent,as well as to polarity,solubil-ity and molecular dimensions of the certain mycotoxin which is to be adsorbed[46].Molecular sizes of aﬂatox-ins range from5.18A˚(B1and B2)to6.50A˚(G1and G2) and only zeolites with entry channels wide enough to permit the diﬀusion of aﬂatoxin molecules to the intra-crystalline structure are capable of demonstrating a clear sequestering eﬀect.Clinoptilolite,a natural zeolite,has high adsorption indexes in vitro,more than80%,for aﬂatoxins B1[48,49]and G2[48]and the adsorption pro-cess begins with a fast reaction whereby most of the toxin is adsorbed within theﬁrst few minutes[48].On the contrary,Lemke et al.[50]conducted a variety of in vitro adsorption studies and reported a limited degree of clinoptilolite ability to bind aﬂatoxin B1eﬀectively. According to them,adsorbent materials should be checked through a multi-tiered system of in vitro tests in order potential interactive factors,such as intestinal physicochemical variables and feed components,to be precluded.Indeed,a previous in vitro study had demon-strated average aﬂatoxin retention in natural zeolites of 60%,but also a nitrogen compound-related adsorbent eﬀectiveness,when liquid media quality parameters had been taken into account[51].The in vivo eﬃcacy of zeolites to ameliorate the consequences of aﬂatoxico-sis,mainly in poultry,has also been veriﬁed in many cases(Table2).In the case of phyllosilicates,the results of in vitro mycotoxin–clay interaction tests suggest the existence of areas of heterogenous adsorption aﬃnities onto sur-face,the presence of diﬀerent adsorption mechanisms or both[57].Nevertheless,the formation of strong bonds by chemisorption and the interaction of b-car-bonyl group of aﬂatoxin B1with the uncoordinated edge site aluminum ions in these adsorbents have been suggested as the binding mechanism which interprets their well-established high aﬃnity for aﬂatoxin B1 [39,58,59].Although the exact binding mechanisms of zeolites on aﬂatoxins have not been determined the pos-sibility to act through similar with phyllosilicates mech-anism cannot be precluded and should be investigated.As far as other mycotoxins are concerned,mineral adsorbents exert a lower eﬃcacy against mycotoxins containing less polar functional groups,which are required for eﬃcient chemisorption on hydrophilic negatively charged mineral surfaces to occur.This limi-tation can be overcome by the use of chemically modi-ﬁed clays.Modiﬁcations consist of alterations ofTable1Proposed mechanisms involved in animalsÕperformance promoting properties of the dietary use of zeolitesMechanismsAmmonia binding eﬀect Elimination of toxic eﬀects of NHþ4produced by intestinal microbial activity[8,10]Fecal elimination of p-cresol Reduction of the absorption of toxic products of intestinal microbial degradation,such as p-cresol[27] Retarding eﬀect on digesta transit Slower passage rate of digesta through the intestines and more eﬃcient use of nutrients[1,25,28] Enhanced pancreatic enzymes activity Favorable eﬀect on feed components hydrolysis over a wider range of pH,improved energy and protein retention[29,30]Aﬂatoxin sequestering eﬀect Elimination of mycotoxin growth inhibitory eﬀects[31–37]162 D.Papaioannou et al./Microporous and Mesoporous Materials84(2005)161–170surface properties resulting in an increased hydropho-bicity,by exchange of structural charge-balance cations with high molecular weight quaternary amines.In vitro results have veriﬁed the binding eﬃcacy of modiﬁed montmorilonite and clinoptilolite against zearalenone and ochratoxin A[60,61].However,naturally occurring clays also exert a moderate binding eﬃcacy against mycotoxins,other than aﬂatoxins,as evidenced for zearalenone and ochratoxin A by in vitro[57]andﬁeld trials[62,63],as well as for cyclopiazonic acid in exper-iments with broilers[45].Remarkable conclusions related to zeolitesÕeﬃcacy against zearalenone toxicosis have also been drawn by in vivo studies.Feeding zearalenone to rats,Smith[64] demonstrated that the dietary use of a synthetic anion exchange zeolite could alter the faecal and urinary excre-tory patterns of zearalenone due to the elimination of its intestinal absorption.Recently,the dietary use of a clin-optilolite-rich tuﬀwas also eﬀective in decreasing zearal-enone and a-zearalenole excretion in pigs fed diets contaminated with500ppb zearalenone[65].Addition-ally,in aﬁeld-case of zearalenone toxicosis with mean concentrations of660ppb,Papaioannou et al.[20] reported that the supplementation of a clinoptilolite rich tuﬀat the rate of2%in the ration of pregnant sows im-plied a rather protective role against the consequences of zearalenone ingestion,as evidenced by the improvement of indicative performance traits.Similar results were also obtained in swine with the dietary use of a modiﬁed clinoptilolite–healandite rich tuﬀat0.2%and with zea-ralenone concentration exceeding3.5ppm[66].Apart from surface interactions,the in vivo eﬃcacy of mineral adsorbents against zearalenone could also re-sult from other implicating mechanisms.The entero-he-patic circulation of zearalenone and its derivatives in pigs retards their elimination and enhances the duration of adverse eﬀects[67].Whether certain types of zeolites are able to aﬀect the entero-hepatic cycling of zearale-none,thus counteracting the toxic eﬀects of its biological action,is a hypothesis that awaits further research, although there is evidence of Ca-enriched clinoptiloliteÕs high aﬃnity to the bile acids in the intestinal tract[68].3.Supportive eﬀect on diarrhoea syndromeThere is an abundance of published data which indi-cate that the dietary use of natural zeolites reduces the incidence and decreases the severity and the duration of diarrhoea in calves[1,69–72]and pigs[1,5,13,72–75]. The exact mechanism of zeolitesÕeﬀect is not quite clear so far,although there is evidence that the use of zeolites may eliminate various predisposing and/or causative fac-tors which are associated in the culmination of intestinal disturbances in an interactive way.Apart from zeolitesÕretarding eﬀect on intestinal passage rate[1]and their water adsorption property,which leads to the appear-ance of drier and more compact faeces,as in the case of phillipsite[75]or clinoptilolite[76],Vrzgula et al.[71]also proposed that the ameliorative eﬀect on diar-rhoea syndrome of calves might result from either the alteration of metabolic acidosis,through eﬀects on os-motic pressure in the intestinal lumen,or the increased retention of the enteropathogenic Escherichia coli.As far as we know,there is no evidence in the available lit-erature for retention of enteropathogenic E.coli on the outer surface of zeolite particles.However,clinoptilolite and mordenite are capable to adsorb and partially inac-tivate the thermo-labile(LT)E.coli enterotoxin in vitro, thus constricting its attachment to the intestinalTable2In vivo studies concerning the eﬀect of the dietary use of zeolites during aﬂatoxicosesType of zeolite Dietary inclusion rate(%)Animal model ObservationsClinoptilolite1Broilers Growth depression caused by2.5ppm aﬂatoxin(aﬂ)was alleviated by15%[31] Clinoptilolite5Geese Prophylactic eﬀect on growth rate and liver enzymatic activity[32]Mordenite0.5Broilers Reducing eﬀect on toxicity of aﬂ(3.5mg kgÀ1diet)as indicated byweight gain and changes in uric acid and albumin concentrations[33] Clinoptilolite0.5Weaned piglets Growth inhibitory eﬀects and alterations of liver enzyme activity inducedby500ppb aﬂwere prevented[34]Synthetic zeolite0.5Broilers No signiﬁcant eﬀect on biochemical or haematological indexes whenadministered simultaneously with2.5mg aﬂkgÀ1diet[52]Clinoptilolite0.5Pregnant rats No eﬀect on maternal and developmental toxicities of aﬂ(2mg kgÀ1body weight)[53]Clinoptilolite5Quail chicks Growth inhibitory eﬀects of2mg kgÀ1diet diminished by70%[35] Clinoptilolite 1.5Broilers Growth inhibitory eﬀects of100ppb aﬂdiminished over a studyperiod of42days[36]Clinoptilolite 1.5–2.5Broilers Adverse eﬀects of2.5mg kgÀ1diet on biochemical and haematologicalproﬁles were reduced[54]Zeolite NaA1Broilers Protection against growth inhibitory eﬀects of2.5mg kgÀ1diet[37] Clinoptilolite 1.5–2.5Broilers Moderate to signiﬁcant decrease of incidence and severity of certaintarget-organs degenerative changes induced by2.5mg aﬂkgÀ1diet[55] Clinoptilolite2Laying hens Signiﬁcant decrease in liver mycotoxin concentration and liver weightduring aﬂatoxicosis caused by2.5mg kgÀ1diet[56]D.Papaioannou et al./Microporous and Mesoporous Materials84(2005)161–170163cell-membrane receptors[77].Furthermore,the adsorp-tion capacity of clinoptilolite and mordenite has been proved to be higher than94%for virions of bovine rota-virus and coronavirus,although infectivity level of zeolite–virus complex seems to remain unchanged[78]. Interactions among virions and the outer surface of adsorbent particles have been proposed,since the former have dimensions considerably larger(60–80nm and 60–220nm for rota-and coronavirus particles,respec-tively)than the entry channels of the aforementioned zeolites.In a more recent study of Rodrigues-Fuentes et al.[68],dealing with the development and the properties of an anti-diarrhoeic drug for humans based on clinop-tilolite,zeolite had no eﬀect on rate of passage of inges-ta,neither acted as a water adsorbent.Instead,they proposed that the anti-diarrhoeic eﬀect of clinoptilolite is due to the adsorption of(i)bile acids,‘‘one of the endogenic causes of diarrhoea’’,(ii)aﬂatoxin B1,‘‘a mycotoxin that produces severe toxicity in animals and humans’’and(iii)glucose,‘‘whose high content in intes-tinalﬂuid acts as an irritant factor and whose transport through the intestinal cells is reversed during diarrhoea’’.Concerning the newborn animals,the administration of zeolites appears to reduce the incidence of diarrhoea through the enhancement of passive immunity,as they increase the net absorption of colostrum immunoglobu-lins in calves[71,79,80]and pigs[81].Intestinal hypersensitivity to feed antigens or the mal-absorption syndrome,induced by a low enzyme activity, can both predispose to post-weaning infectious enteritis in pigs.According to Papaioannou et al.[13],clinoptil-olite has the ability to adsorb dietary substances,which may result in intestinal hypersensitivity phenomena[82], or to support the maintenance and even the restoration of the digestive enzyme activity in newly weaned piglets. This should also be evaluated in future studies as an additional explanation for clinoptilolitesÕminimising ef-fect on diarrhoea syndrome.4.Prevention of metabolic diseases in dairy cowsMilk fever and ketosis are of the most common metabolic diseases in high producing dairy cows.In the recent years,a number of experiments have been con-ducted in order to control these diseases using zeolites as feed additives.The results of these experiments are very promising but further investigation is required to deﬁne the exact mechanisms of zeolitesÕaction.k feverInitially,a series of experiments has been conducted in order to study the potential use of synthetic zeolite A for the prevention of milk fever in dairy cows.The objective of these experiments was to reduce the bio-availability of dietary Ca in the gastrointestinal tract by the administration of synthetic zeolite A,based on the evidence that one of the best ways to prevent milk fever is to feed cows with low calcium diets during the dry period[83–87].The results obtained were satisfac-tory as the administration of synthetic zeolite A,either as an oral drench or supplemented to the total mixed ra-tion,during the dry period reduced the bioavailability of dietary Ca and eﬃciently protected against milk fever, by stimulating Ca-homeostatic mechanisms prior to par-turition[88–93].Furthermore,Thilsing-Hansen et al.[92]proposed that the best ratio zeolite/Ca for the pre-vention of milk fever was10–20and that zeolite had the same eﬃciency either administrated for the last4 or2weeks of the dry period.More recently,Katsoulos et al.[94]showed that clin-optilolite was eﬀective in the prevention of milk fever as well.The incidence of milk fever was signiﬁcantly lower in cows that were receiving a concentrate supplemented with clinoptilolite at the level of2.5%(5.9%)during the last month of the dry period and the onset of lactation compared to the animals in the control group(38.9%), which were not receiving clinoptilolite,whereas was not signiﬁcantly diﬀerent than those that were receiving 1.25%clinoptilolite(17.6%)with the concentrates at the same period.The authors suggested that clinoptilolite might have had similar eﬀect with zeolite A in activating Ca homeostatic mechanisms prior to parturition.As a consequence,the animals receiving2.5%clinoptilolite responded faster and more eﬃciently in the drop of serum Ca observed at the day of calving and did not show any clinical signs of milk fever the following days. However,the exact mechanism for this positive eﬀect of clinoptilolite is currently unknown and should be fur-ther investigated.4.2.KetosisThe best strategy to prevent ketosis in dairy cows is to improve the energy uptake both in the dry period and the onset of lactation[95].According to Katsoulos et al.[23],the use of clinoptilolite has been shown to be eﬀective in improving the energy balance at this critical period as they observed that feeding dairy cows on a diet supplemented with clinoptilolite at the level of2.5%of the concentrate feed,resulted in signiﬁcantly lower incidence of ketosis(5.9%)during theﬁrst month after parturition,compared to the control group(38.9%) and the group of the animals receiving a concentrate supplemented with1.25%clinoptilolite(35.3%).These researchers suggested that clinoptilolite improved the energy status of the cows,either via prepartum enhance-ment of propionate production in rumen or through the improvement of the post-ruminal digestion of starch.164 D.Papaioannou et al./Microporous and Mesoporous Materials84(2005)161–1705.Protective role in intoxications and poisonings5.1.Ammonia toxicityWhite and Ohlrogge[96]ﬁrst stated that ammonium ions formed by the enzyme decomposition of non-pro-tein nitrogen were immediately ion exchanged into the zeolite structure and held there for several hours until released by the regenerative action of Na+,entering the rumen in saliva during the after-feeding fermenta-tion period.From both in vitro and in vivo experimentsthey found that up to15%of the NHþ4in the rumencould be taken up by the zeolite.These observations were the causation for the conduction of many experi-ments in order to determine the inﬂuence of zeoliteson rumen NHþ4concentration and their potential usefor the counteraction of the toxic eﬀects of urea inclu-sion in ruminantsÕrations.Hemken et al.[97]showed that supplementation of 6%clinoptilolite,in the ration of dairy cows containing urea,signiﬁcantly reduced rumen NH3concentration. The same trend was observed by the dietary addition of5%clinoptilolite in steers[98]and lambs[99].Fur-thermore,clinoptilolite was eﬀective in reducing rumen ammonia concentration even when no urea was present in the ration of steers receiving a high concentrate diet, and that this reduction was linearly associated to the percentage of clinoptilolite inclusion[100].Nestorov [101]referred that simultaneous administration of clin-optilolite and urea in sheep protects rumenﬂora from toxic eﬀects of ammonia by inhibiting the reduction of microbiota population.In contrast to the former observations,Bergero et al.[102]and Bosi et al.[103]found that daily administration of250g or200g of clinoptilolite, respectively,in dairy cows did not aﬀect rumen NHþ4 concentration.The same result had the dietary inclu-sion of2%synthetic zeolite A in dairy cows ration [104]and5%clinoptilolite in steers receiving a high roughage diet[98].The binding of NHþ4to zeolites has been noted in pigsas well,and many researchers suggested this action as the possible mechanism for the observed improved per-formance of the animals receiving zeolites.There are evi-dences that clinoptilolite elevates nitrogen excretion in feces[8,105]and reduces the ammonia concentration in blood serum[8,10,106],when supplemented to the basal diets of pigs.Furthermore,Pond et al.[10]and Yannakopoulos et al.[12]found that clinoptilolite reduced the weight of the organs involved in the metab-olism of ammonia(liver and kidneys),as the conse-quence of the reduced ammonia concentration in the gastrointestinal tract.Such observations result fromthe direct binding of NHþ4to zeolites,as clinoptilolitehas no adverse eﬀect on the ureolytic bacteria of the large intestine and urease activity[107]anophosphate poisoningThe dietary use of clinoptilolite appears to be eﬀective in the prevention of organophosphates poisoning. Experiments in sheep have shown that the oral adminis-tration of clinoptilolite at the dose of2g/kg of body weight,earlier or simultaneously with an organophos-phate(VX),partially protects from poisoning by inhib-iting the decrease in cholinesterase activity[108]and by protecting rumenﬂora[109].The protective eﬀect of clinoptilolite on cholinesterase activity has been ob-served in mice receiving higher doses of organophos-phates as well[110,111].5.3.Heavy metal toxicity and adsorption of radioactive elementsZeolites,due to their high ion-exchange capacity, have been used eﬀectively for the prevention of heavy metal toxicity in animals.Pond et al.[112]found that clinoptilolite protects growing mice from lead(Pb)tox-icity when added to their ration in such quantities that the ratio clinoptilolite/Pb to be10/1.According to Pond et al.[113],similar protection is provided in swine as well.The selectivity of clinoptilolite for cadmium(Cd) and Pb has been studied in vitro in order to be investi-gated whether its use reduces the levels of these elements in rumen and abomasalﬂuid.The experiments showed that clinoptilolite bent the91%of Pb and the99%of Cd in rumenﬂuid within24h,and in the abomasalﬂuid the94%of Pb within less than1h[114].The toxic eﬀects of long-term ingestion of Cd(100ppm CdCl2)on female rats and their progeny were not diminished by the simul-taneous feeding of a clinoptilolite-rich tuﬀat5%in the diet[115].Adversely,the eﬃcacy of clinoptilolite against Cd toxicity has been proved in pigs by the same authors who observed that3%clinoptilolite supplementation prevented the cadmium-induced iron deﬁcient anemia in growing swine that were receiving150ppm CdCl2 [116].The results of these experiments suggest the feasi-bility of using zeolites and mainly clinoptilolite as a feed additive in the prevention of certain types of heavy metal intoxications in farm animals or in aquatic biolog-ical systems,as is the case in the study of Jain[117], where is ascertained the capacity of zeolite to enhance the removal of Pb from water,thus decreasing its avail-ability to the teleostﬁsh Heteropneustes fossilis.Apart from heavy metals,zeolites can also bind radioactive elements,thus being suggested as a means of altering their uptake and excretion from the body. Zeolitic matrix exchanges radio-nuclides in the gastroin-testinal tract and is excreted by normal processes,there-by eliminating radioactive elementsÕassimilation into the body.Arnek and Forsberg[118]proved the selectiv-ity of some natural zeolites such as clinoptilolite, chabazite and modernite for cesium and GomonajD.Papaioannou et al./Microporous and Mesoporous Materials84(2005)161–170165et al.[119]the selectivity of clinoptilolite for strodium and zirconium.Phillippo et al.[120]showed that the dietary use of clinoptilolite may constitute a simple and cost-eﬀective method for minimizing the adsorption of radioactive cesium by sheep grazing contaminated pastures,although there might be no eﬀect on cesium already been built-up in the body due to a previous exposure.Furthermore,Forsberg et al.[121]observed that the administration of mordenite in sheep and goats increased the excretion of cesium with feces and reduced its accumulation in tissues.On the other hand,Rachu-bik and Kowalski[122]demonstrated that synthetic zeolite-enriched diets exerted an inconsistent pattern of radiostrontium assimilation in the bone tissue and liver or kidneys of rats intragastrically dosed with an aqueous solution of90SrCl2.5.4.Copper toxicityIvan et al.[123]observed that the inclusion of ben-tonite,a phyllosilicate,in the ration of sheep at the rate of0.5%signiﬁcantly reduced the Cu concentration in liver and suggested the use of this material in order to prevent copper poisoning.In contrast,clinoptilolite does not seem to be eﬀective,as Pond[124]found that the addition of2%clinoptilolite to the basal diet of sheep containing10or20ppm Cu did not protect against the toxic signs of Cu and increased the mortality in lambs fed the diet with20ppm Cu.A lack of any ef-fect on liver Cu accumulation was also found in growing pigs which were on diets supplemented with0.5%syn-thetic zeolite A and250ppm Cu[125].Clinoptilolite was expected to exchange Cu in the lumen of the intes-tine,thereby decreasing the toxicity of excess Cu for sheep,whose tolerance for Cu is low compared with that of other food animals.However,such action was not observed probably due to a shift in ion-exchange relativeto Cu and NHþ4or to some other complex interaction,which resulted in a net increase in Cu available for absorption from the intestinal tract[124].The optimum ratio of clinoptilolite to Cu in the diet for reducing the intestinal absorption of the latter has not been deter-mined,but such information,according to Pond[126], is needed in order to establish appropriate levels of die-tary clinoptilolite supplementation.6.Impact on parasite infectionsConsidering the potential eﬃcacy of zeolites against parasite infections,the results of the experimentsﬁrst conducted in rats were encouraging for their use in other animal species as well.According to Wells and McHugh [127],the administration of clinoptilolite at the rate of 10%of a conventional diet facilitated the removal of parasites from the intestinal lumen of rats infected with the nematode Nippostrongylus brasiliensis.Furthermore, Wells and Kilduﬀ[128]observed a more accelerated intestinal a-D-glucosidase and aminopeptidase activity restitution in rats fed a commercial diet supplemented with clinoptilolite(5%)and recovering from N.brasilien-sis infection.Conﬁrming the observations in rats,Deli-giannis et al.[129]recently proved the eﬃcacy of clinoptilolite against parasite infections in growing lambs.They showed that feeding lambs,primarily infected with a single dose of gastrointestinal(GI) nematodes,with a concentrate mixture containing3% clinoptilolite signiﬁcantly decreased their total worm burden and faecal egg counts per capita fecundity and demonstrated that clinoptilolite supplementation re-duced the establishment of GI nematodes and resulted in a good performance of the animals.Interestingly,zeolites have also been tested as anthel-mintic loaded carriers,through retarding drug release and prolonging its therapeutic action.Sustained-release mechanism implies a slow desorption of the drug mole-cules from the external surface and the internal zeolitic cavities,as they are progressively replaced by host pro-teins and water molecules,respectively,during the intes-tinal transport of the drug-zeolite compound.Promising results were obtained,atﬁrst,as regards tetramisole-loaded synthetic zeolite Y[130]and recently,pyrantel-and fenbendazole-loaded synthetic zeolite Y in rats infested with N.brasiliensis and dichlorvos-loaded zeo-lite Y in pigs infected with Ascaris suum[131].In the case of tetramisole and dichlorvos,anthelmintic mole-cules are small enough toﬁt through the entry channels of zeolite Y(windows of7.4A˚),while fenbendazole loading requires an initial partial dealumination of the zeolitic carrier and large pyrantel molecules allow only outer surface loading to occur.7.Prevention of metabolic skeletal defectsThe dietary inclusion of synthetic zeolite A(at the rates of0.75%or1.5%)in broilers which are on a diet with inadequate or marginal levels of calcium results in an increase of bone ash content along with a reduc-tion of rachitic lesions[132].Accordingly,the incorpora-tion of zeolite A in the same diets at1%exerts a clear beneﬁcial eﬀect in reducing the incidence of tibial dys-chondroplasia[132–134].Although tibial dyschondro-plasia is a metabolic cartilage disease which represents the endpoint of several mechanisms,the incidence is in-creased when high dietary levels of phosphorus are used [135]or when dietary calcium is lower than0.85%[136]. Similarly,the beneﬁcial eﬀect of zeolite A is inconsistent and largely depends on the dietary level of calcium. According to Watkins and Southern[137],the dietary use of0.75%zeolite A in broilers is accompanied by alterations in mineral absorption and tissue distribution,166 D.Papaioannou et al./Microporous and Mesoporous Materials84(2005)161–170。

A radio study of the superwind galaxy NGC1482

Mon. Not. R. Astron. Soc. 000, 1–?? ( )Printed 2 February 2008A (MN L TEX style ﬁle v1.4)A radio study of the superwind galaxy NGC 1482Ananda Hota1,2⋆ and D.J. Saikia2†1 2Joint Astronomy Programme, Indian Institute of Science, Bangalore 560 012, India National Centre for Radio Astrophysics, TIFR, Pune University Campus, Post Bag 3, Pune 411 007, IndiaarXiv:astro-ph/0411628v1 23 Nov 2004Accepted. ReceivedABSTRACTWe present multifrequency radio continuum as well as H i observations of the superwind galaxy NGC1482, with both the Giant Metrewave Radio Telescope (GMRT) and the Very Large Array (VLA). This galaxy has a remarkable hourglass-shaped optical emission line outﬂow as well as bi-polar soft X-ray bubbles on opposite sides of the galactic disk. The low-frequency, lower-resolution radio observations show a smooth structure. From the non-thermal emission, we estimate the available energy in supernovae, and examine whether this would be adequate to drive the observed superwind outﬂow. The high-frequency, high-resolution radio images of the central starburst region located at the base of the superwind bi-cone shows one prominent peak and more extended emission with substructure. This image has been compared with the infrared, optical red-continuum, Hα, and, soft and hard X-ray images from Chandra to understand the nature and relationship of the various features seen at diﬀerent wavelengths. The peak of infrared emission is the only feature which is coincident with the prominent radio peak, and possibly deﬁnes the centre of the galaxy. The H i observations with the GMRT show two blobs of emission on opposite sides of the central region. These are rotating about the centre of the galaxy and are located at ∼2.4 kpc from it. In addition, these observations also reveal a multicomponent H iabsorption proﬁle against the central region of the radio source, with a total width of ∼250 km s−1 . The extreme blue- and red-shifted absorption components are at 1688 and 1942 km s−1 respectively, while the peak absorption is at 1836 km s−1 . This is consistent with the heliocentric systemic velocity of 1850±20 km s−1 , estimated from a variety of observations. We discuss possible implications of these results. Key words: galaxies: individual (NGC1482) – galaxies: active – galaxies: starburst – galaxies: kinematics and dynamics – radio continuum: galaxies – radio lines: galaxies1INTRODUCTIONGalactic-scale outﬂows along the minor-axes of nearby edgeon galaxies have been observed over a wide frequency range extending from radio continuum to X-ray wavelengths. The more prominent outﬂows with an outﬂow mass and kinetic energy of approximately 105 − 107 M⊙ and 1053 − 1055 ergs respectively are often referred to as superwinds, and these have been observed over a wide range of redshifts (e.g. Heckman, Armus & Miley 1990; Pettini et al. 2001; Veilleux 2002a, 2003). The superwind could contain diﬀerent phases of the metal enriched interstellar medium (ISM) such as hot X-ray emitting gas, warm ionized gas emitting ultraviolet (UV) and optical emission lines, synchrotron emitting relativistic plasma and magnetic ﬁelds, dust, as well as H iand molecular gas (Dahlem 1997; Strickland 2001). These superwinds play an important role in heating and supplying kinetic energy to the Inter Galactic Medium (IGM) and enriching it with metals. Many of these outﬂows are interpreted as the combined eﬀect of numerous supernovae and stellar winds in the nuclear starforming region of the parent Seyfert or starburst galaxy. An active galactic nucleus (AGN) or winds from the tori in the nuclear regions could also contribute to the observed outﬂows (Heckman et al. 1990; Balsara & Krolik 1993; Baum et al. 1993; Krolik & Kriss 1995; Colbert et al. 1996a,b; Weaver 2001; Veilleux 2002b). In this paper we present a detailed radio study of the interesting superwind galaxy NGC1482, which has received relatively little attention. The basic properties of this galaxy are summarised in Table 1. In an emission-line survey of early-type spirals Hameed & Devereux (1999) noticed the presence of “ﬁlaments and/or chimneys of ionized⋆ hota@ncra.tifr.res.in † djs@ncra.tifr.res.in c RAS2Ananda Hota and D.J. SaikiaTable 1. Basic Data on NGC 1482.a RA (J2000)b (h m s) 03 54 38.92 DEC (J2000)b (◦ ′ ′′ ) −20 30 07.6 Typec SA0/a a × bd (′ × ′ ) 2.5 × 1.4 Vsys e (km s−1 ) 1850±20 if (◦ ) 58 log(LF IR )g (L⊙ ) 10.66 Dh (Mpc) 24.7a Taken from the NASA Extragalactic Database (NED), unless stated otherwise. b The position of radio peak from our high-resolution, VLA A-array, 8460 MHz image c Morphological type. d Optical major and minor axes. e Heliocentric optical systemic velocity (Veilleux & Rupke, private communication). This is consistent with H i observations of Roth et al. (1991) and those presented in this paper. f Inclination angle, from Strickland et al. (2004). g Log of the far infra-red luminosity (Condon et al. 1990) using the revised distance. h Distance estimated using the galaxy recessional velocity with respect to the cosmic microwave background radiation and H0 =71 km s−1 Mpc−1 (Spergel et al. 2003). For this distance 1′′ =120 pc.gas extending perpendicular to the disk”. Veilleux & Rupke (2002) imaged the galaxy in Hα and N ii and highlighted the remarkable hourglass-shaped optical emission line outﬂow with a velocity of ∼250 km s−1 . They estimated the energy in the optical emission-line outﬂow to be at least 2×1053 ergs. The ionization ratios of the gas in the superwind have been interpreted to be due to shock formation in the outﬂow. More recently, Veilleux et al. (2003 and private communication) have reported an outﬂow velocity of ∼460 km s−1 in one of the ﬁlaments. The soft X-ray image from the Chandra Observatory also exhibits bipolar emission along a similar axis to that of the optical hourglass-shaped structure (Strickland et al. 2004). We have studied this galaxy at radio continuum wavelengths ranging from 335 MHz to 14965 MHz as well as in H i using both the GMRT and the VLA. While VLA images at 1.49 GHz have been presented by Condon et al. (1990), continuum observations at lower and higher frequencies as well as H i images have been presented here for the ﬁrst time. The objectives of the observations were to clarify the radio structure, constrain the energetics and explore evidence of outﬂow at radio wavelengths. We ﬁrst brieﬂy describe the observations in Section 2. The large-scale radio structure, its comparison with the images at other wavelengths, and some of the implications are discussed in Section 3. The small-scale radio structure and a comparative study of this with features seen at other wavelengths are also presented in Section 3. Section 4 describes the H i observations, where we report the detection of both emission and absorption lines, discuss these results and compare with the spectral information at optical and CO wavelengths. In Section 5 we summarise the conclusions.Table 2. Log of the radio observations Telescope GMRT GMRT VLA-BnA GMRT VLA-A VLA-BnA VLA-A VLA-A Freq. MHz 335 615 1365 1409,H i 4860 8460 8460 14965 Obs. date 2002Aug17 2003Mar07 2002May20 2002Nov16 2003Jun26 2002May20 2003Jun26 2003Jun26 t min 60 180 25 180 54 23 60 20 Phase Calib. 0521−207 0453−281 0416−188 0453−281 0416−188 0416−188 0416−188 0348−278 Scal. Jy 9.67 2.21 2.85 1.99 0.68 0.68 0.83 1.02of the error in the ﬂux density is approximately 10% at 335 and and 5% at the higher frequencies.2.1GMRT2OBSERVATIONS AND DATA ANALYSESThe observing log for both the GMRT and VLA observations is presented in Table 2, which is arranged as follows. Column 1: Name of the telescope where we also list the conﬁguration for the VLA observations. Column 2: The frequency of the observations where H i denotes spectral line observations centred at an observed frequency of ∼1412 MHz. Columns 3 and 4: Dates of the observations and the time, t, spent on the source. Columns 5 and 6: The phase calibrator used and its ﬂux density. A conservative estimateThe GMRT consists of thirty antennas, each of 45 m diameter, in an approximate ‘Y’ shape similar to the VLA but with each antenna in a ﬁxed position. Twelve antennas are randomly placed within a central 1 km by 1 km square (the “Central Square”) and the remainder form the irregularly shaped Y (6 on each arm) over a total extent of about 25 km. Further details about the array can be found at the GMRT website at http://www.gmrt.ncra.tifr.res.in. The observations were made in the standard fashion, with each source observation interspersed with observations of the phase calibrator. The primary ﬂux density calibrator was 3C286 whose ﬂux density was estimated on the Baars et al. (1977) scale, using the latest (1999.2) VLA values. The bandwidth of the continuum observations at 335 and 615 MHz was 16 MHz, while for the L-band observations it was 8 MHz. The data analyses were done using the Astronomical Image Processing System (AIPS) of the National Radio Astronomy Observatory. Since GMRT data is acquired in the spectralline mode, gain and bandpass solutions were applied to each channel before combining them. The 335 MHz observations were aﬀected by ionospheric phase ﬂuctuations. A signiﬁcant amount of data had to be edited, and the ﬁrst round of phase self-calibration was done assuming a point source model. In the subsequent runs of self-calibration the image of the target source was used as the model. The position ofc RAS, MNRAS 000, 1–??A radio study of the superwind galaxy NGC 1482NGC14821 2 33R-band4NGC148212335 MHz + R-band34NGC1482-20 29 151365 MHz-20 29 1530-20 29 153030DECLINATION (J2000)30 0030 00DECLINATION (J2000)45DECLINATION (J2000)454530 00151515303045304531 004531 0031 0003 54 43424103 54 43424140 39 38 37 RIGHT ASCENSION (J2000)36353440 39 38 37 RIGHT ASCENSION (J2000)36353403 54 43 42 41 40 39 38 37 RIGHT ASCENSION (J2000) 36 35 34Levs = 2.172E-03 * (-4, -2.82, 2.820, 4, 5.650, 8, 11.31, 16, 22.62, 32, 45.25, 64, 90.50, 128, 181.0, 256)Levs = 2.000E-04 * (-4, -2.82, 2.820, 4, 5.650, 8, 11.31, 16, 22.62, 32, 45.25, 64, 90.50, 128, 181.0, 256)Figure 1. Left panel: An optical R-band image of NGC1482 . Middle panel: The GMRT 335-MHz contour image restored with a circular beam of 11.6 arcsec superimposed on the optical R-band image in grey scale. Right panel: The VLA BnA-array image at 1365 MHz with an angular resolution of 5.13×2.23 arcsec along a PA∼62◦ .the source was determined by aligning its peak with that of the 615 MHz image. The analyses of the H i observations were also done in the standard way. 3C286 was the primary ﬂux density and bandpass calibrator. The total bandwidth for H i observations was 8 MHz and the spectral resolution was 62.5 kHz, which corresponds to 13.3 km s−1 in the centre of the band. We discarded any antennas with more than 3% ﬂuctuations in the bandpass gains during the observations. A few channels in the beginning and approximately ten channels towards the end were also not included in the analyses. The AIPS task UVLIN was used for continuum subtraction and the multi-channel data were then CLEANed using IMAGR. Some of the observed parameters of the GMRT and the VLA continuum images are presented in Table 3 which is arranged as follows. Columns 1 and 2 are similar to that of Table 2, except that we also list the parameters from the NRAO VLA Sky Survey (NVSS). Columns 3 to 5: The resolution of the image with the major and minor axes being listed in arcsec and the position angle (PA) in degrees. Column 6: The rms noise in units of mJy/beam. Columns 7 and 8: The peak and total ﬂux densities in units of mJy/beam and mJy respectively. In addition to the rms noise in the image, we also examined the change in ﬂux density by varying the size of the box around the source. The error in the ﬂux density is approximately 10% at 335 MHz and 5% at the higher frequencies. 2.2 VLAshorter baselines, over the uv ranges speciﬁed in the VLA Calibrator manual. These values of the phase calibrator ﬂux density were incorporated using the task GETJY, and are also listed in Table 2. We attempted to make self-calibrated images for all the diﬀerent data sets. However, the A-array images did not improve after self calibration. Therefore, BnA-array images presented here are self-calibrated ones, while the A-array ones are not.3 3.1RADIO CONTINUUM EMISSION Large-scale structureThe VLA observations were also made in the standard way with a phase calibrator being observed before and after each scan on a source. The primary ﬂux density calibrator was 3C286. However, since 3C286 is signiﬁcantly resolved on the longer baselines at 14965, 8460 and 4860 MHz with the VLA A-array, the following procedure was adopted. The ﬂux density of 3C286 was calculated by the AIPS task SETJY. The ﬂux density of the phase calibrator was estimated by comparing its visibility amplitude with those of 3C286 at thec RAS, MNRAS 000, 1–??In Fig. 1 we show the optical R-band image of the galaxy (Strickland et al. 2004; and Strickland, private communication), our GMRT 335-MHz contour map superimposed on the optical image and our VLA BnA-array 1365-MHz image. The GMRT 335-MHz image, which has an angular resolution of 11.6 arcsec shows the source to be resolved with a deconvolved angular size of 14×8 arcsec along a PA of 107◦ . Its angular dimensions are less than that of the optical galaxy, and shows no evidence of a large-scale outﬂow or halo due to diﬀusion of cosmic ray particles. This is consistent with the NVSS image where the source appears to be a single source with a 45 arcsec beam. The GMRT 615-MHz image is essentially similar to the 335-MHz image and is not shown here, although the ﬂux density estimates are listed in Table 3. The somewhat higher-resolution VLA 1365-MHz image, which has a lower rms noise than the low-frequency GMRT images, shows the central region to be very clearly extended along a PA∼105◦ , but again with no evidence of any large-scale diﬀuse emission. A comparison of the radio image with the Chandra soft X-ray bubbles of plasma shows that the X-ray emission extends far beyond the radio extent as seen in the 335-MHz image (Fig. 2). The non-thermal synchrotron emission appears largely conﬁned to the disk of the galaxy, with no signiﬁcant emission from the outﬂowing superwind plasma.4Ananda Hota and D.J. SaikiaNGC14821 2 3The GMRT images do not appear to have missed significant emission from any diﬀuse component. A comparison of the GMRT ﬂux densities with the known and reliable ﬂux density measurements listed by NED (Fig. 3) shows that these values are consistent with the overall straight, nonthermal spectrum of the source with a spectral index, α, of 0.82 (S∝ ν −α ) between 335 and 1400 MHz. We have not attempted to make a spectral index image from the lowresolution images since the number of beamwidths along the source is small. Adopting the spectral index of 0.82 as the mean value over the region of emission, and assuming the synchrotron emission to have lower and higher cutoﬀs at 107 and 1010 Hz respectively, a proton to electron ratio of unity, a ﬁlling factor of unity and an oblate spheroidal distribution for the emitting region we estimate the minimum energy density and equipartiton magnetic ﬁeld to be ∼5.9×10−11 ergs cm−3 and 25 µG respectively. The radiative life time of an electron radiating in this ﬁeld at 1.4 GHz is ∼2.2×106 yr. These values are similar to estimates for nearby galaxies (e.g. Condon 1992). The proton to electron ratio is not well determined for external galaxies. For a value of ∼50 from studies of cosmic rays in our own Galaxy (e.g Webber 1991), the equipartition magnetic ﬁeld would increase by a factor of ∼2.5. Since the overall spectral index is steep, the contribution of the thermal fraction to the total emission is expected to be small. Using the expression due to Condon (1992) for the thermal fraction in spiral galaxies, as measured globally, we estimate that only 4, 7 and 11 per cent of the total emission could be due to thermal components at 335, 615 and 1400 MHz respectively. From the non-thermal emission, we estimate the supernova rate in this galaxy to be ∼0.14 yr−1 (Condon 1992). The supernova rate appears similar to estimates in other starburst galaxies such as ∼0.1 yr−1 for M82 (e.g. Huang et al. 1994), <0.1 to 0.3 for NGC253 (Ulvestad ∼ & Antonucci 1997), ∼0.1 yr−1 for the clumpy irregular starburst galaxy Mrk 325 (Condon & Yin 1990) and also for the starburst galaxy NGC3448 of the Arp 205 system (Noreau & Kronberg 1987) and ∼0.07 yr−1 for NGC6951 (Saikia et al. 2002). We can examine whether the energy the from the estimated supernova rate is adequate to drive the observed superwind outﬂow. Adopting a value of 1051 ergs for the kinetic energy of a supernova, the available energy over the dynamical lifetime of the bubble, ∼7.5 × 106 yr, is ∼ 1057 ergs. However, the energy which drives the outﬂow depends on the heating eﬃciency of the supernovae, i.e. the fraction of supernova energy which is not radiated away. In a classic paper, Larson (1974) estimates that approximately 10 per cent of the explosion energy is eﬀectively transmitted to the gas. There is a wide range of values in the literature, with many of the simulations of galactic winds assuming a heating eﬃciency of 100 per cent. Melioli & de Gouveia Dal Pino (2004) note that this is often not consistent with the observations, and that the heating eﬃciency may be time dependent and sensitive to the initial conditions of the system, and cannot be assumed to be 100 per cent. For our purposes we assume an eﬃciency of 10 per cent, so that the available energy is ∼ 1056 ergs. Veilleux & Rupke (2002) estimate the kinetic energy involved in the outﬂow of the warm ionized gas to be >2×1053 n−1 ergs, where n−1 is the e,2 e,2 ∼335 MHz + X-ray4-20 29 1530DECLINATION (J2000)4530 0015304531 0003 54 43424140 39 38 37 36 RIGHT ASCENSION (J2000)3534Levs = 2.172E-03 * (-4, -2.82, 4, 16, 64, 128, 256)Figure 2. The GMRT 335-MHz contour image with an angular resolution of 11.6 arcsec superimposed on the soft X-ray image from Chandra X-ray observatory.Table 3. Observed parameters of radio continuum images Telescope Freq. MHz 335 615 1365 1400 1409 4860 8460 8460 14965 Beam size maj. min. PA′′ ′′ ◦rms mJy /b 2.24 0.65 0.17 0.50 0.60 0.04 0.07 0.02 0.09Spk mJy /b 370 140 35 23 21 1.9 1.3 0.9 <0.3Stot. mJy 723 397 198 224 218 44 25 18GMRT GMRT VLA-BnA NVSS GMRT VLA-A VLA-BnA VLA-A VLA-A11.6 8.24 5.13 45.0 2.96 0.64 1.06 0.36 0.2011.6 5.44 2.23 45.0 2.01 0.35 0.55 0.20 0.110 178 62 0 25 12 46 9 5number density in units of 100 cm−3 . They estimate the number density of particles in the entrained material to be <100 cm−3 from their [S ii]λ6731/6716 line ratios. The total ∼ kinetic energy involved in the outﬂow could be signiﬁcantly larger. In addition to the optical line-emitting gas and the known X-ray plumes, there could also be cold gas entrained in the ﬂow. For example, for a sample of far-infrared bright, starburst galaxies, Heckman et al. (2000) estimate the kinetic energy in the cool gas to be ∼1055 ergs. In the case of NGC1482, we need a reliable estimate of total energy in the outﬂow before determining whether the observed supernova rate is adequate to drive the outﬂow.c RAS, MNRAS 000, 1–??A radio study of the superwind galaxy NGC 1482100 ’NED, NVSS’ ’present paper’-20 30 025NGC14824860 MHz10041DECLINATION (J2000)Flux density (Jy)06080.1100.0112140.001 1e+081e+091e+101e+111e+121e+131e+141e+1516 03 54 39.6 39.4 39.2 39.0 38.8 RIGHT ASCENSION (J2000) Cont peak flux = 1.9464E-03 JY/BEAM Levs = 3.154E-05 * (-4, -2.82, 2.820, 4, 5.650, 8, 11.31, 16, 22.62, 32, 45.25, 64, 90.50, 128, 181.0, 256) 38.6 38.4 38.2Frequency (Hz)Figure 3. The integrated spectrum of NGC1482 using values from NED, NVSS (+)and from the observations presented here (×).-20 30 02NGC14828460 MHz3.2Small-scale structureDECLINATION (J2000)04The 4860 MHz, VLA A-array image (Fig. 4) shows a prominent peak of emission with a brightness of 1.95 mJy/beam and more diﬀuse emission along a PA of ∼100◦ , similar to the orientation of the galaxy. The diﬀuse emission is more prominent on the eastern side of the peak, the total ﬂux density on this side being 27 mJy compared with 15 mJy on the western side. The brightest feature on the eastern side, which we call the secondary peak, is located at RA: 03 54 39.12, Dec: −20 30 08.60 and has a peak brightness of 0.65 mJy/beam. This image shows a sharper boundary on the southern side than on the northern one, as is also seen in the VLA BnA-array image at 1365 MHz (Fig. 1). The somewhat lower-resolution VLA BnA-array, 8460 MHz snap-shot image shows basically a similar structure with the peak brightness being 1.30 mJy/beam. Smoothing the 4860 MHz image to that of the BnA array 8460 MHz one yields a peak brightness of 2.38 mJy/beam and a spectral index of ∼1 for the prominent peak of emission. The spectral index of the central region between 4860 and 8460 MHz is also ∼1, showing that the entire region has a steep radio spectrum. The expected brightness of this peak of emission at 14965 MHz with a similar resolution to that of the VLA BnA-array image is ∼0.7 mJy/beam. Its non-detection with a 3σ upper limit of ∼0.3 mJy/beam in the image with a resolution of ∼0.15 arcsec is consistent with this. Although its steep spectral index does not suggest it to be an AGN, it is diﬃcult to rule out the possibility of there being a weak AGN with more extended emission associated with it. It is relevant to note here that from optical spectroscopic observations, Kewley et al. (2000) have classiﬁed it to be a starburst galaxy without an AGN. The brightness temperature of the peak of emission, estimated from the 4860 MHz image (e.g. Condon et al. 1991) is only ∼630◦ K making it diﬃcult to use it as a diagnostic to identify whether it is an AGN. The VLA A-array 8460 MHz image with a resolution of ∼0.27 arcsec shows the peak feature to have a possible extension to the south and again more emission on the eastern side of this peak (9 mJy) compared with the western side (6 mJy). The peak brightness here is 0.9 mJy/beam. The brightness temperature estimated for the peak is ∼740◦ K.c RAS, MNRAS 000, 1–??060810121416 03 54 39.6 39.4 39.2 39.0 38.8 RIGHT ASCENSION (J2000) Cont peak flux = 1.3016E-03 JY/BEAM Levs = 7.321E-05 * (-4, -2.82, 2.820, 4, 5.650, 8, 11.31, 16, 22.62, 32, 45.25, 64, 90.50, 128, 181.0, 256) 38.6 38.4 38.2NGC14828460 MHz-20 30 0204DECLINATION (J2000)06081012141603 54 39.6 39.4 39.2 39.0 38.8 RIGHT ASCENSION (J2000) Cont peak flux = 9.0944E-04 JY/BEAM Levs = 2.524E-05 * (-4, -2.82, 2.820, 4, 5.650, 8, 11.31, 16, 22.62, 32, 40, 50, 60, 70, 80, 90, 100, 200, 300, 400)38.638.438.2Figure 4. Top panel: VLA A-array image at 4860 MHz with an angular resolution of 0.64×0.35 arcsec along a PA∼12◦ . Middle panel: VLA snapshot image with the BnA array at 8460 MHz. The angular resolution is 1.06×0.55 arcsec along a PA∼46◦ . Bottom panel: VLA A-array image at 8460 MHz with an angular resolution of 0.36×0.20 arcsec along a PA∼9◦ .6Ananda Hota and D.J. SaikiaNGC1482 0 1 2 3 4860 MHz + R-band 4NGC1482 0 10 20 304860 MHz + H alpha 40-20 30 02-20 30 02 04DECLINATION (J2000)DECLINATION (J2000)040606 08 10 1208101214141616 03 54 39.6 39.4 39.2 39.0 38.8 38.6 RIGHT ASCENSION (J2000) 38.4 38.203 54 39.639.439.2 39.0 38.8 38.6 RIGHT ASCENSION (J2000)38.438.2Peak contour flux = 1.9695E-03 JY/BEAM Levs = 3.154E-05 * (2.820, 4, 5.650, 8, 11.31, 16, 22.62, 32, 45.25, 64, 90.50, 128, 181.0, 256)Peak contour flux = 1.9695E-03 JY/BEAM Levs = 3.154E-05 * (-4, -2.82, 2.820, 4, 5.650, 8, 11.31, 16, 22.62, 32, 45.25, 64, 90.50, 128, 181.0, 256)4860 MHz + hard x-rayNGC1482 0 10 20NGC1482 100 200 3004860 MHz + K-band 400 5003040-20 30 02-20 30 02 0404DECLINATION (J2000)DECLINATION (J2000)0606 08 10 12 14 16 03 54 39.80810121416 03 54 39.6 39.4 39.2 39.0 38.8 38.6 RIGHT ASCENSION (J2000) 38.4 38.239.639.439.2 39.0 38.8 38.6 RIGHT ASCENSION (J2000)38.438.2Peak contour flux = 1.9478E-03 JY/BEAM Levs = 3.154E-05 * (2.820, 4, 5.650, 8, 11.31, 16, 22.62, 32, 45.25, 64, 90.50, 128, 181.0, 256)Peak contour flux = 1.8393E-03 JY/BEAM Levs = 3.154E-05 * (-4, -2.82, 2.820, 4, 5.650, 8, 11.31, 16, 22.62, 32, 45.25, 64, 90.50, 128, 181.0, 256)Figure 6. The 4860 MHz VLA A-array contour map with an angular resolution of 0.64×0.35 arcsec along a PA∼12◦ is shown superimposed on an optical R-band image (upper left), narrow-band Hα image (upper right), the Chandra 2-8 keV hard X-ray image (lower left) and the infrared K-band 2MASS image (lower right) of only the central region of the galaxy.The linear resolution in the VLA A-array 8460 MHz image is approximately 30 pc, and its peak luminosity is 6.5×1019 W Hz−1 . The peak luminosity in the other regions of the source is typically 1018 W Hz−1 . It is of interest to compare this with other galaxies. For example, the median luminosity at 8.4 GHz of the components observed in M82 which is at a distance of 3.4 Mpc is ∼2×1018 W Hz−1 (Huang et al. 1994; Allen & Kronberg 1998) when observed with a linear resolution of ∼3 pc. Considering a more distant galaxy, the median luminosity for the archetypal starburst galaxy in the southern hemisphere, NGC1808 (distance∼10.9 Mpc), is about 8×1018 W Hz−1 with a linear resolution of 30 pc (Collison et al. 1994). The luminosities in NGC1482 appear similar to the discrete features in some of the well-known archetypal starburst galaxies.3.3Comparison with other wavebandsThe high-resolution radio images, which deﬁne the structure of the circumnuclear starburst region, consist of one prominent peak of emission and several weaker secondary peaks. A superposition of the VLA 4860 MHz image on the optical, hourglass-shaped structure traced by the Hα emission (Fig. 5) shows that the starburst region lies at the base of this structure, and possibly provides the energy to drive the outﬂow. The 4860 MHz image and the two Hα peaks of emission at the extremeties appear to lie along a line perpendicular to the axis of the outﬂow. The 4860 MHz image appears displaced to the north in the central visible Hα region of emission; this apparent displacement could be largely due to obscuration of the northern part by the dust lane. In order to understand the nature of the prominent rac RAS, MNRAS 000, 1–??A radio study of the superwind galaxy NGC 1482NGC14820.2 0.4 0.674860 MHz + H alpha0.8 1.0 1.2Table 4. Nuclear emission peaks at diﬀerent wavebands Peaks RA(J2000) 03 03 03 03 03 03 03 03 54 54 54 54 54 54 54 54 38.92 38.92 39.10 39.31 39.05 39.18 38.92 39.18 Dec.(J2000) −20 −20 −20 −20 −20 −20 −20 −20 30 30 30 30 30 30 30 30 07.5 07.6 08.2 10.1 11.2 10.5 09.3 09.9-20 29 1530DECLINATION (J2000)4530 00Radio 4860 MHz Radio 8460 MHz X-ray West X-ray East Hα West Hα East R-band West R-band East15304531 0003 54 43424140 39 38 37 RIGHT ASCENSION (J2000)363534Levs = 3.154E-05 * (4, 15, 40)Figure 5. The VLA A-array 4860 MHz image, superimposed on the grey scale image of Hα emission. Only three of the radio contours are shown.dio peak we have compared the 4860 MHz radio image with the optical R-band continuum, Hα, hard X-ray and infrared images (Fig. 6). The positions of the peaks in J2000 coordinates at the diﬀerent wavelengths are listed in Table 4. These positions have been estimated from the FITS images kindly provided by Strickland and Veilleux (private communication). The R-band image shows two prominent peaks of emission with the peak brightness of the eastern one being brighter by a factor of ∼1.14, and a dust lane to the north. The northern part of the the 4860 MHz image is seen through the dust lane. The R-band peaks possibly arise due to a combination of enhanced emission in the sites of star formation and diﬀerential extinction in the circumnuclear region. These peaks skirt the southern edge of the radio continuum image and are not coincident with the radio peak. The Hα image also shows two peaks of emission with the maximum value for the eastern one being brighter than the western one by a factor of ∼2. The Hα peaks also lie along the southern boundary of the image, are within ∼1.′′ 5 of the peaks in the R-band image, and are not coincident with the radio peaks. The 2 to 8 keV hard X-ray Chandra image also shows two compact peaks of emission. Such features have been seen in a number of nearby starburst galaxies such as M82 (Zezas et al. 2001), NGC4038/4039 (Zezas et al. 2002) and NGC3256 (Lira et al. 2002), and are interpeted to be due to X-ray binaries or supernova remnants. In NGC1482, the western hard X-ray peak is within 0.5 arcsec of the secondary radio peak (see Fig. 6). The point source subtracted hard Xray image (Strickland et al. 2004), not shown here, reveals more extended emission coincident with the secondary peak in the 4860 MHz image. These are possibly due to one or more supernova remnants. The eastern hard X-ray peak (seec RAS, MNRAS 000, 1–??Fig. 6) lies at the southern edge of the radio image and does not have any compact component associated with it. No hard X-ray peak is seen at the position of the prominent peak in the radio image. A superposition of the radio image on the infrared 2MASS (2 Micron All Sky Survey) K-band image (Jarrett et al. 2003) shows the infrared peak to be coincident with the prominent radio peak. The infrared image, which is largely due to a population of old giant stars, also appears asymmetric with more emission on the eastern side than the western one. This asymmetry is similar to what is seen in the radio image, and reﬂects a greater degree of circumnuclear activity on the eastern side of this peak. The coincidence of the radio and infrared peaks suggest that this is possibly the centre of the galaxy. The centre of the galaxy estimated from the outer isophotes of the R-band image is at RA 03 54 38.91 and Declination −20 30 07.2, which is within an arcsec of the radio peak in the high-resolution images. The geometrical centre of a line joining the peaks of the red- and blue-shifted H i emission blobs (RA: 03 54 38.8 and Dec.: −20 30 10 in J2000 co-ordinates, Section 4.1) is within 2 arcsec of this position, and hence co-incident with it within the errors.4H I OBSERVATIONSThe H i spectra towards diﬀerent regions of the galaxy show signiﬁcant H i emission from two diametrically opposite regions located at a distance of ∼20 arcsec from the nuclear region, while H i in absorption is seen against the radio continuum source. These observations which have an rms noise of ∼0.6 mJy/beam per channel are described below.4.1H i emissionThe global H i proﬁle from a tapered image with an angular resolution of 8.19×6.52 arcsec along a PA of 36◦ is shown in Fig. 7. This spectrum has been obtained by specifying a box around the visible extent of the galaxy, and there is a hint that it could be double-humped. The heliocentric velocities at zero intensity range from ∼1690 to 2020 km s−1 , indicating a systemic velocity of 1855±20 km s−1 . The total width is ∼330 km s−1 , similar to that of typical spiral galaxies. The published H i spectrum by Roth, Mould & Davies (1991) is very similar and has a central velocity of 1859 km s−1 with a velocity resolution of 7.3 km s−1 . The total H i ﬂux density estimated from our spectrum is 9±1 Jy km s−1 , implying。

《眼科学词汇翻译》word版

眼科学词汇翻译ophthalmology, OPH, Ophth 眼科学visionics 视觉学visual optics 视觉光学visual physiology 视觉生理学physiology of eye 眼生理学visual electro physiology 视觉电生理学pathology of eye 眼病理学dioptrics of eye 眼屈光学neuro ophthalmology 神经眼科学ophthalmiatrics 眼科治疗学ophthalmic surgery 眼科手术学cryo ophthalmology 冷冻眼科学right eye, RE, oculus dexter, OD 右眼left eye, LE, oculus sinister, OS 左眼oculus uterque, OU 双眼eyeball phantom 眼球模型eye bank 眼库prevention of blindness, PB 防盲primary eye care 初级眼保健low vision 低视力blindness 盲totol blindness 全盲imcomplete blindness 不全盲congenital blindness 先天性盲acquired blindness 后天性盲曾用名“获得性盲”。

functional blindness 功能性盲organic blindness 器质性盲occupational blindness 职业性盲legal blindness 法定盲visual aura 视觉先兆visual disorder 视觉障碍visual deterioration 视力减退transitional blindness 一过性盲amaurosis 黑●amaurosis fugax 一过性黑●toxic amaurosis 中毒性黑●central amaurosis 中枢性黑●uremic amaurosis 尿毒性黑●cortical blindness 皮质盲macropsia 视物显大症曾用名“大视”。

observations中文翻译

observations中文翻译"Observations"的中文翻译可以是"观察"、"观测"或者"观察结果"。

以下是一些关于"observations"的中英文对照例句和用法：1. The scientist made detailed observations of the bird's behavior. 科学家对鸟的行为进行了详细的观察。

2. Her observations led to significant discoveries in the field of astronomy. 她的观测结果在天文学领域带来了重大的发现。

3. The teacher asked the students to write down their observations during the experiment. 老师要求学生们在实验过程中记录下观察结果。

4. Through careful observations, the researchers were able to identify a new species of insect. 通过仔细观察，研究人员成功鉴定了一种新的昆虫物种。

5. The police officer's observations were crucial in solving the crime. 警察的观察结果对破案起到了关键作用。

6. The book contains a collection of observations about human behavior. 这本书收集了关于人类行为的观察。

7. The scientist used a microscope to make magnified observations of the cells. 科学家使用显微镜对细胞进行放大观察。

全息干涉与散斑干涉综述

全息干涉与散斑干涉技术综述报告全息干涉无损检测技术是无损检测技术中的一个新分支，它是20世纪60年代末期发展起来的，是全息干涉计量技术的重要应用。

我们知道结构在外力的作用下，将产生表面变形。

若结构存在缺陷，则对应缺陷表面部位的表面变形与结构无缺陷部位的表面变形是不同的。

这是因为缺陷的存在，使得缺陷部位的结构的刚度、强度、热传导系数等物理量均发生变化的结果。

因而缺陷部位的局部变形与结构的整体变形就不一样。

应用全息干涉计量技术就可以把这种不同表面的变形转换为光强表示的干涉条纹由感光介质记录下来。

而激光散斑技术是在激光全息实验中，我们观察被激光所照射的试件表面，就可以看到上面有无数的小斑点，因而观察不到条纹，因此在前期，散斑是被看作是噪声来对待的，直到随着人们对全息干涉技术的进一步了解，才发现虽然这些斑点的大小位置都是随机分布的，但所有的斑点综合是符合统计规律的，在同样的照射和记录条件下，一个漫反射表面对应着一个确定的散斑场，即散斑与形成散斑的物体表面是一一对应的。

在一定范围内，散斑场的运动是和物体表面上各点的运动一一对应的，这就启发人们根据散斑运动检测，来获得物体表面运动的信息，从而计算位移、应变和应力等一些力学量。

因此全息和激光散斑方法由于其固有的高灵敏度，在非破坏性测试领域发现了越来越多的应用。

可探测到表面及地下的裂缝、空洞、脱层和分层等缺陷。

由于这些方法测量了在外部加载或其他条件的影响下，在这三个维度下研究对象的变形，它们也可以用于质量控制，也可以用于设计阶段。

激光散斑的方法，还利用了电子检测和处理的发展(称为电视全息术)，并可用于实时定量评价。

本综述报告主要介绍利用光纤光刻技术，对全息和激光散斑测量方法进行了全面的研究，这两种方法都适用于焊接、复合材料的检验。

IntroductionHolography is a two step process of recording a wavefrontand then reconstructing the wave. While Holography is oftenused to obtain the recreations of beautiful 3-dimensional scenes,there are several engineering applications, the most common andimportant one being Holographic Non-Destructive Testing . Thisis accomplished with holographic interferometry, whereininterferometry is carried out with holographically generatedwavefronts .A speckle pattern is generated when an object with a roughsurface is illuminated with a highly coherent source of lightsuch as laser. Initially this speckle noise was considered asthe bane of holographers, until it was realized that these specklescarry information about the surface that produce them. Again,as in the case of holography, the combination of interferometric concepts with speckle pattern correlation gave rise to speckle interferometry . The developments in electronic detection and processing further added wings to laser speckle methods giving rise to Electronic Speckle Pattern Interferometry (ESPI), or “TV Holography”. This paper describes a brief outline of holographic and speckle methods for Non-Destructive Testing applications, wherein the deformations of an object under load are measured in a non-contact way. Measurement of surface shapes using contouring and derivatives of displacement using Shearography are also presented.1.HolographyThe schematic for recording a hologram is shown in Fig.1. The light from a laser is split into two beams. One beam illuminates the object and the other beam is used as a reference. At the recording plane, an interference of theFig. 1 : Experimental arrangement for recording a hologram. wavefront scattered by the object with the reference wavefront takes place. A recording is made on a high resolution photographic plate. The developed plate, now called a “Hologram”, when illuminated by the reference wave, reconstructs the object wave. There are several recording geometries such as in-line, off-axis, image plane, Fourier Transform, reflection and rainbow holograms. The theory behind the recording and reconstruction of object wavefront is well documented .1.1Holographic Interferometry (HI)While holography is used to obtain recreations of beautiful 3-D scenes, most engineering applications of holography make use of its ability to record slightly different scenes and display the minute differences between them. This technique is called Holographic Interferometry (HI). Herewe deal with Interference of two waves of which atleast one of the waves is generated holographically.Methods of Holography Interferometry are classified as (i) Real-time HI, (ii) Double-Exposure HI, and (iii) Time average HI. In holographic interferometry, we record the holograms of the two states of an object under test, one without loading and one with loading. When such a doubly exposed hologram is reconstructed, we see the object superposed with a fringe pattern which depicts the deformation undergone by the object due to loading. The theory behind the fringe formation in HI is as follows [3]:Let the O1 and O2 represent the undeformed and deformed object waves, which are written asO1(x，y) = |O(x，y)| exp[-i Φ(x，y)] (1)O2(x，y) = |O(x，y)| exp[-i Φ(x，y) + δ] (2) where δis the phase change due to displacement or deformation of the object. The intensity due to superposition of these two waves isI(x，y) = |O1(x，y) + O(x，y)|2= O1O1* + O2O2* + O1O2* + O1* O2= I1 + I2+ 2I1I2Cos δ(3)where I1 and I2 are the intensities of O1 & O2. The Phase Difference δ is given byδ = (K2-K1).L (4)where K2 is the observation vector, K1 is the illumination vector and L is the displacement vector. Thus the evaluationof the phase δis gives the displacement. The fringes formed represent contours of constant displacement.1.2Holographic Non-Destructive Testing (HNDT)This powerful technique of Holographic interferometry, is an invaluable aid in Engineering design, Quality Control and Non-Destructive testing and Inspection. In HNDT, the object under study is subjected a very small stress or excitation and its behavior is studied using HI.The defects in the object can be spotted as an anomaly in the otherwise regular fringe pattern. HNDT is a highly sensitive, whole-field, non-contact technique and is applicable to objects of any shape and size. The types of excitation used for HNDT are mechanical, thermal, pneumatic or vibrational. Defects such as cracks, voids, debonds, delaminations, residual stress, imperfect fits, interior irregularities, inclusions could be seen. HNDT is applied to inspect the disbonds between the plies of an aircraft tyre, delamination of the composite material of a helicopter rotor blade, PCB inspection, rocket castings, pressure vessels, andso on.Use of double-pulsed laser makes HI more attractive for study of transients and impact loads. Fig.2 shows the double exposure hologram of a turbine blade subjected to an impact loading (recorded using a double-pulsed Ruby laser).Fig. 2 : Double-pulse hologram of a turbine blade impact loaded with a small metallic ball.Time average HI, wherein a hologram of a vibratingobject is recorded, provides information about the modes and the vibration amplitudes at various points on the object. Figs.3(a) and (b) show the time average holograms of a rectangular plate vibrating at 1826 Hz and 5478 Hz, from which the resonant mode patterns could be easily studied . In HNDT, this technique is used for study of vibrations of machinery, car doors, engines and gear boxes and to identify the points where they should be bolted to arrest the vibration and noise.Fig. 3 : (a) and (b) Time averaged hologram of a centrally clamped plate at (0,0) and (1,0) mode when vibrated at 1826 Hzand5478Hz respectively2 22 22. Electronic Speckle Pattern Interferometry(ESPI)Recent holographic applications in engineering use a video camera for image acquisition, which is coupled to a computer image processing system. This is termed as TV Holography, though technically called Electronic Speckle Pattern Interferometry (ESPI). The technique makes use of the speckle pattern produced when an object with a rough surface is illuminated with a laser [4-6]. The correlation between the speckle patterns, before and after an object is deformed, are carried out using image processing techniques. Figure 4 shows the schematic of an ESPI system. The object is illuminated by the light from a laser and is imaged by a CCD camera. An in-line reference beam, derived from the same laser, is added at the image plane. The specklecorrelation is carried out by storing an image while the object is in its initial state, and subtracting the subsequent frame fromthis stored frame, displaying the difference on the monitor. When the object is subjected to some loading or excitation, the correlated areas appear black while the uncorrelated areas would be bright, resulting in a fringe pattern. As in HI,the fringes represent contours of constantdisplacement of the object points.The fringe formation in ESPI is well documented . The intensity distributions I 1(x,y) and 12(x,y) recorded before and after the object displacement respectively can be written asFig. 5 : Measurement of Poisson’s ratioI I (x,y) = a 1 +a 2 + 2a 1a 2 cos(ϕ) (5) I 2(x,y) = a 1 +a 2 + 2a 1a 2cos(ϕ+δ) (6)Fig. 4 : Experimental arrangement for ESPIFig. 6 : (a) Delamination in a plate (b) Longitudinal crack in asteel weldmentwhere a 1 and a 2 are the amplitudes of the object and reference waves, δ is the phase difference between them and ϕ is the additional phase change introduced due to the objectmovement. The subtracted signal as displayed on the monitor is given by,I 1 - I 2 = 4 |a 1a 2 Sin[ϕ + (δ/2)] Sin (d/2)|(7)Thus we find the brightness is modulated by a sine factor of the phase. The brightness on the monitor is maximumFig. 7 : Fiber Optic Shearography systemwhen δ = (2m +1)π and zero when δ = 2m π, which producesa fringe pattern on the monitor. The phase change δ is given by equation [4], the same as in holography. Figure 5 shows such an interferogram obtained by ESPI with a plate subjected to four-point bending, from which the Poisson’s ratio of the material of the plate could be calculated directlyfrom the smaller angle between the asymptotes of the hyperbolic fringes [8]. Figure 6(a) shows the delamination between two plates bonded together, while Fig. 6(b) shows a longitudinal crack in a weldments [9].4. Shearography In Shearography, we generate correlation fringes which are contours of constant slope of the out-of-plane displacement of an object under study . In this technique, one speckle field is made to interfere with the same speckle field, but sheared with respect to it. The subtractive correlation of the speckle patterns of the deformed and undeformed yields the derivatives of the displacement profile. Figure 7 shows the schematic of a fiber optic Shearography system. A double image of the laser illuminated object is made on the CCD camera. A small shear is introduced between the two images by tilting one of the mirrors. Incorporation of fiber optics makes the system very compactand the technique applicable to objects at inaccessible locations. Shearography is a very useful tool in experimental stress analysis and NDT as well. With the use of phase shifting techniques, the fringe patterns can also be automatically processed by the computer to obtainquantitative 3-dimensional plots . Figure 8 shows the results of an NDT application of Shearography to detect delamination in glass fiber reinforcedplastic (GFRP). The GFRP specimens were prepared withunidirectional glass fiber mat and epoxy resin with and without programmed defects. The defects were introduced by placing a thin Teflon film of 10 mm diameter and thickness 0.23mm between the layers of glass fiber mat during the lamination. Four layers of Glass fiber mat were used to make the laminate. The specimens were made in the form of circular diaphragm. The diaphragm was clamped along the edgesanFig. 8 : Slope fringes obtained on a circular GFRP specimen which was (a) Defect free (b) Having a programmed delaminationloaded mechanically at the center. The optical configuration of Fig. 8 was used, which is sensitive to the slope of the out- of-plane displacement. Figure 8(a) shows the fringes obtained with a defect-free specimen, while Fig. 8(b) shows the fringeswhen a delamination was introduced between the third and fourth layers. The defect site could be easily seen as a localized fringe. 全息无损检测主要还是采用全息干涉计量技术的三种方法进行，即实时全息干涉法，两次曝光全息法和时间平均全息干涉法。

分子生物学双语专业单词总结

nuclei nucleus 的复数形organelle细胞器assembly集合, 装配, 集会, 集结, 汇编covalent共有原子价的, 共价的Protist原生生物algae藻类, 海藻schematic示意性的图解的, (按照)图式[公式]的compartment区划，区分；间隔，部分bound跳跃, 限制ester[化]酯differentiation区别, 差别; 划分【生】分化, 变异【数】微分法, 求导数spore孢子embryonic[生]胚胎的, 开始的phylogenetic 系统发生的, 动植物种类史的precursor产物母体, 先质, 前体,原先neuron[解]神经细胞, 神经元Polysaccharides多糖glycosidic bonds糖苷键monomer单体gel凝胶(体), 冻胶, (肉、鱼、果子等的)冻tissue【生】组织embed使插入, 使嵌入, 深留, 嵌入, [医]包埋esterify(使)酯化constituent要素；组分［元，件saturated渗透的, 饱和的, 深颜色的choline胆碱intermediate中间的，媒介exterior外部的, 外在的, 表面的, 外交的, [建](适合)外用的peripheral外围的，外围设备neurotransmitter【生化】神经递质, 神经传递素degrade降解; 使退化dipole偶极Dispersion 分散aliphatic脂肪族的, 脂肪质的aromatic【化】芳香族的tertiary第三的, 第三位的, 第三世纪的ray光线, (放、辐)射线crystallography结晶学chiral[化][物]手(征)性的aqueous水的, 水成的amphoteric两性的(酸与碱)collagen【生化】（骨）胶原，成胶质ionize使离子化neutrality 中立, 中性protonate[化]使质子化,给…加质子hydroxyl【化】羟基thiol巯醇Disulfide bond 二硫键Alkyl 烷基ultraviolet radiation紫外线prosthetic groups 辅基conjugate结合；连接；module模数, 模块duplication副本, 复制successive继承的, 连续的divergent发散的, 扩散的, 辐散的, 渐扩的, 非周期变化的ancestral祖先的; 祖传的; 遗传的functionality功能性,泛函性complementary补充的, 补足的coil盘绕, 卷terminus终点, [建]界标, 终点站pleat使...打褶curl(使)卷曲regular规则的, 有秩序的, 经常的, (花)整齐的, 常备军的, 等边的, 合格的, 定期的adjacent邻近的, 接近的parallel平行的, 相同的, 类似的, 并联的minor较小的, 次要的, 二流的, 未成年的disruption中断, 分裂, 瓦解, 破坏conformation构造［象］；形态；结构，组成identical 同一的, 同样的aggregate合计, 总计, 集合体incorporate合并的, 结社的, 一体化的entity实体allosteric[生化]变构(象)的conjugated偶联residue【化】残基;contraction收缩, 缩写式, 紧缩MW分子量Nuclear Magnetic ResonanceNMR核磁共振magnetic磁的, 有磁性的, 有吸引力的resonance共鸣, 回声, 反响, 中介, 谐振, 共振, 共振子prior优先的, 在前的filtration过滤, 筛选isoelectric[物]等电位的, 零电位差的chromatography色谱法bead珠子, 水珠ultracentrifugation超速离心法sedimentation沉淀, 沉降emerge显现, 浮现, 暴露, 形成,ligand配体antigen抗原spectrometry[物]光谱测定法,度谱术vaporize(使)蒸发deflection偏斜,偏转, 偏差electromagnetic电磁的desorption解吸附作用slide滑, 滑动, 幻灯片laborious(指工作)艰苦的, 费力的, (指人)勤劳的derivative派生的事物, 派生词deduce论, 推断, 演绎(from) probe探针, 探测器immobilize 固定不动elute【化】洗脱[提]diffraction【物】(光, 声等的)衍射, 绕射, 折射Proteomics蛋白质组学intact 完整无缺的alignment队列, 结盟novel新奇的, 新颖的, 异常的cluster使成群；把...集成一束gradient坡度; 梯度strip条, 带annealing退火alkali[化]碱,碱性的viscosity粘质, 粘性buoyant有浮力的, 轻快的spectroscopic[物]分光镜的, 借助分光镜的hyperchromicity增色现象, 增色性topoisomerase拓扑异构酶bicyclic双环的pentose sugar戊糖nitrogenous[化]氮的, 含氮的stack堆, 一堆, 堆栈nomenclature 命名法, 术语backbone脊椎, 中枢, 骨干, 支柱, 意志力, 勇气, 毅力, 决心analogous类似的, 相似的, 可比拟的axis轴planar平面的，平坦的diameter直径tilt(使)倾斜glycosyl[生化]糖基crystallize使结晶, 晶化，明确correspond符合, 协调, 通信, 相当, 相应endogenous[生]内长的, 内生的favorable赞成的, 有利的, 赞许的, 良好的, 讨人喜欢的, 起促进作用的exclude拒绝接纳, 把...排除在外, 排斥formic蚁的, 蚁酸的subtle狡猾的, 敏感的, 微妙的, 精细的, 稀薄的tautomeric effect互变(异构)效应keto(酮)form enolate(烯纯) form Urea(H2NCONH2) (尿素）bulk大批, 大量，大部分, 主要部分, 大多数reduce减少, 缩小, 简化, 还原stiff硬的, 僵直的, 拘谨的, 呆板的shear(修)剪, 剪羊毛pellet小球equilibrium平衡, 平静, 均衡centrifugation离心法，离心过滤hypochromicity减色现象extinction消失, 消灭, 废止, [物]消光Extinction coefficients(消光系数)destruction破坏, 毁灭Hybridization(杂交)duplex双的, 二倍的, 二重的counter相反地，相反的，反对的；反击的torsional扭力的, 扭转的facilitate使容易, 使便利, 推动, 帮助, 使容易, 促进Gyrase(旋转酶) resolve使分[溶]解, 使解体; 解析writhe扭曲, 扭歪geometry几何学constant常数, 恒量；不变的, 持续的, 坚决的partition区分, 隔开, 分割isomer异构体reseal重封; 再密封; 重新填缝intercalate设置(闰日、闰月等), 插入compound混合物, [化]化合物restore恢复, 使回复, 归还, 交还, 修复, 重建central dogma【生化】中心法则framework构架, 框架, 结构scaffold[建] 脚手架,绞刑台microscope显微镜secure保护condense(使)浓缩, 精简rotation旋转intrinsical本质的, 固有的cleave劈, 劈开, 裂开Histone octamer(组蛋白八聚体)cocci[微生物]球菌trimmed平衡的; 纵倾的nuclease[生化]核酸酶bead用珠装饰; 把...连成一串solenoid[电]螺线管mitotic有丝分裂的, 间接核分裂的dissociation分解, 分离; 游离radial光线的, 光线状的, 放射状的,centromere(着丝点)Heterochromatin 异染色质Euchromatin(常染色质)chromatid[生物]染色单体flank在...的侧面, 侧翼包围, 守侧面spindle (纺锤体)diffuse散开的, 弥漫的;散播, 传播, 漫射, 扩散, (使)慢慢混合homogeneous同类的, 相似的, 均一的, 均匀的deplete耗尽, 使衰竭scarce缺乏的, 不足的, 稀有的, 不充足的coincident with (与…一致)variant变体; 变形modulate调整, 调节, (信号)调制acetylation(乙酰化)utilization利用tandem串联的, 级联的intersperse散布, 点缀sonication(超声波)moderate中等的, 适度的, 适中的;温和的haploid单倍体cluster群，球；簇scattered离散的，分散的bulk松密度; 胀量kinetochore[生]动粒, 着丝粒, 着丝点cryptic秘密的, 含义模糊的, 神秘的, 隐藏的comprise包含, 由...组成drosophila果蝇Genetic polymorphism遗传多态性substitution 代入法, 置换transversion易位allele等位基因clinic diagnosis临床诊断phylum门indicate指出, 显示, 象征, 预示lagging 滞后progeny子代bidirectional双向的comprise包含, 由...组成coordinate（使）协调，调整replication bubbles (复制泡)adjacent邻近的, 接近的fuse合并, 结合一起interpretation解释, 阐明, 口译, 通译DNAligase连接酶spin旋转, 离心nascent初期的; 初生的, 新生的crucial至关紧要的fidelity 忠实, 诚实, 忠诚, 保真度vitro( 离体)gene locus基因座位facilitate使容易, 使便利, 推动, 帮助recruit使恢复, 补充, 征募wrap缠绕, 包, 覆盖, 裹DNA gyrase促旋酶,旋转酶inhibitor[化]抑制剂, 抑制者proofreading (校正)clamp (嵌紧)scrutiny (监视)processive前进的,进行的,向前的joint共同的, 联合的, 连接的, 合办的junction连接, 接合, 交叉点, 汇合处entry 进入, 入口Clusters(族,群)simultaneously同时地Licensing factor (许可因子)prior优先的, 在前的optimal最佳的, 最理想的tuned调谐的, 已调谐的factory工厂, 制造厂depict描述, 描写scaffold (支架)insoluble不能溶解的, 不能解决的analog类似物, 相似体overhanging (突出于)repress压制prolific多产的, 丰富的, 大量繁殖的Mutagenesis (诱变)heritable (可遗传的)phenotypic表型的truncated缩短了的,被删节的Genetic polymorphisms(遗传多态性)accumulation积聚, 堆积物scramble使混杂; 搅乱carcinogens (致癌剂)deaminating脱氨基de-剥夺, 分离Intercalators(嵌入剂)incorporate(使)合并, 并入, 合编lesion损害, 身体上的伤害suppression 镇压, 抑制reversal (恢复)Spontaneous lesions (自发性损伤)Bulky adducts (聚化加合物)distortion (变形) cleavage劈开, 分裂electrophilic[化]亲电子的readily (迅速地)hereditary世袭的, 遗传的defect过失, 缺点recessive(隐性)homozygotes纯合子homologous相应的, 类似的, 一致的, [生物]同源的chromatid[生物]染色单体haploid生物]单倍体,invasion入侵integration综合stimulation刺激, 鼓舞, 兴奋(作用staggered 交错illegitimate (异常)Screening libraries (筛选文库)strain【生】(品)系, 菌株, 变种propagation (增殖)subtraction减少oligo-nucleotide (寡核苷酸)Recreated vectors(自环化载体)devise设计, 发明, 图谋,Replica (影印)absorbent pad (吸水垫), 氨苄青霉素抗性基因(ampr)β-galactosidase(β-半乳糖苷酶)pioneered (开辟)utilized (利用) integrate使成整体, 使一体化lysogenic溶原的,产噬的compatible谐调的, 一致的, 兼容的concatamers(多联体)spread (涂布)supernatant浮在表面的reconstitute重新组成, 重新设立therapy治疗Electro-poration(电穿孔)pipette吸液管Micro-projectiles (微枪)metallic金属(性)的crown加冕, 顶上有repetitive重复的, 反复性的fraction小部分, 片断, 分数shear剪, 修剪, 剪切exogenous外部发生的, 外源的fractionate分级[离, 别], 把...分成几部分condense(使)浓缩, 精简junk垃圾, 舢板elute【化】洗脱[提]magnetic磁的, 有磁性的, 有吸引力的lysate[生化]溶解产物sucrose[化]蔗糖signature信号;用法说明wheat germ extract麦芽汁抽提培养液protrude突出bake烘焙, 烤, 烧硬immersed浸入的, 沉入的counterpart副本, 极相似的人或物, 配对物posit安置distal远侧的; 末端的segment段, 节, 片断Southern and northern blotting(DNA和RNA斑点杂交)polarity极性verify检验, 校验, 查证, 核实lane（乡间）小路, 巷, 里弄capillary毛细管;毛状的, 毛细作用的vacuum真空的, 产生真空的, 利用真空的stringency (紧严性)imprint留下烙印frog青蛙forensic(法医的)optimization最佳化, 最优化nested嵌套的pathogen病菌, 病原体retardation延迟ascribe归因于, 归咎于Medical diagnosis (医学诊断)kit成套工具, 用具包, 工具箱, 成套用具propagate繁殖, 传播, 宣传breed品种, 种类gland腺Maternity (母系)paternity (父系)pedigree (血统)marrow髓, 骨髓, 精华, 活力ladder梯子, 阶梯basic基本的, 碱性的gatekeeper看门人dictate命令, 支配aberrant异常的retain保持, 保留subsequent后来的, 并发的duplication副本, 复制polarity极性income收入, 收益, 进款, 所得outcome结果, 成果nomenclature命名法, 术语convention大会, 协定, 习俗, 惯例locally在地方上, 在本地, 局部地, 本地性invert使颠倒, 使转化consensus一致同意, 多数人的意见, 舆论cylindrical 圆柱的convert使转变, 转换...,使...改变信仰assign分配, 指派diminish(使)减少, (使)变小supplemental补足的, 追加的migrate移动, 移往, 移植, 随季节而移居, (鸟类的)迁徙abortive早产的, 流产的, 失败的ternary三重的nascent初生的rear后面的, 背面的, 后方的temporal时间的, 当时的, 暂时的,circuitry电路, 线路disaccharide (二糖)chemoauxotroph(化学营养缺陷型)exclusively排外地, 专有地diffusible可散播的, 可传播的, 扩散性的potent有力的, 有效的tetramer四聚物magnitude数量, 巨大, 广大, 量级allolactose异乳糖contiguous邻近的, 接近的, 毗边的defective有缺陷的, (智商或行为有)欠缺的catabolic分解代谢的,异化的attenuator弱化子;precede衰减器span横越领先(于), 在...之前, 先于successive继承的, 连续的Attenuation（弱化作用）occlude使闭塞, 使锢囚subtle狡猾的, 敏感的, 微妙的, 精细的, 稀薄的Sporulation孢子形成Transient短暂的, 瞬时的viability生存能力, 发育能力partition分割, 划分, 瓜分, 分开, 隔离物discard丢弃, 抛弃substitute代替, 替换, 替代endow ( 提供)cascade小瀑布, 喷流counterpart副本, 极相似的人或物, 配对物homologous [生物]同源的hepta七nascent初生的ancillary补助的, 副的Recruit使恢复, 补充, 征募sponsor发起人, 主办者, 保证人, 主办人saddle马鞍, 鞍座, 车座dyad对, 双, 成对物Kink弯曲印迹(imprint)blot弄污dimerization[化]二聚(作用)modulate调整, 调节, (信号)调制ligand[化]配合基[体], 向心配合(价)体steroid类固醇swap交换dissect解剖; 剖开, 切开; 分割homeodomain (同源结构域)anchor抛锚, 锚定tetrahedral有四面的, 四面体的coordinate调整, 整理compact紧凑的, 紧密的, 简洁的comprise包含, 由...组成clamp夹住, 夹紧monomeric单节显性的repertoire系统blob一滴, 水滴, 斑点glucocorticoid(糖皮质素)Constitutive组织的；要素的；本质的，基本的ubiquitous (广泛存在的)diffuse漫射, 扩散Interferon干扰素intracellular细胞内的immunodeficiency免疫缺陷prematurely过早地, 早熟地processive前进的,进行的,向前的fibroblast纤维原细胞myotomes(肌节)somite体节embryonic[生]胚胎的, 开始的undergo经历, 遭受, 忍受yield产, 生长, 生产removal切除trim整理, 修整, 装饰moiety二分之一, 一部分, 半族disperse使)分散, (使)散开, 疏散rill小河, 小溪embed使插入, 使嵌入, 深留machinery机器, 机械Cleft 裂缝, 隙口protuberance突起stalk茎, 柄, 梗, 秆cavity洞, 空穴intervene干涉, 干预, 插入, 介入therapeutic治疗的, 治疗学的heterogeneous nuclear RNA (hnRNA:核内不均一RNA)occurrence发生, 出现, 事件, 发生的事情lariat套索proximity接近, 亲近vertebrate脊椎动物substantially充分地immunoglobulin 免疫球蛋白truncated (截短的)sequentially继续地, 从而。

医学英语词汇(35)

医学英语词汇（35）speak 说，讲，陈述speaker 扬声器，话筒，喇叭speaking tube 传音筒spear drill 矛状锥，剑尖锥spear point drill 剑尖锥spear poing flat drill 剑尖平锥Spec. (1.specification 2.specimen) ①说明书②标本special ①特殊的，专门的②专刊special accessories 专用附件special digital computer 专用计算机special effect generator 特技效果发生器specialist 专家speciality 特点，专业specialize 专门化，特殊化，限定special licence 特别许可证special procedure equipment 特殊程序设备special purpose computer 专用计算机species 种类specific 特有的，专门的，比（的）specific activity 比活性specification (abbr. Spec.) ①说明书②规格，规范specific density 比重specific gravity (abbr. sp. gr.) 比重specific gravity balance 比重天平specific gravity bottle 比重瓶specific heat 比热specific ion electrode 离子选择电极specificity 特异性，专一性specific ratio 比率specific resistance 电阻率，比电阻specific value 比值specific volume 比容specific weight 比重specify ①规定，指定②详细说明specillum 探子，探杆specimen 标本，样品specimen bottle 样本瓶specimen copy 样本specimen disc 样品盘specimen holder 标本夹specimen jar 标本缸specimen trap 标本收集器specimen trimmer 标本粗割机specimen vial 标本管形瓶spectacles 眼镜，平光眼镜spectral 光谱，频谱的spectral lamp 光谱灯spectral line 光谱线spectral phonoangiography 光谱血管音描记术spectral phonocardiogram 光谱心音图spectral phonocardiograph 光谱心音描记器spectro- 光谱，分光spectrochrome 色光谱的spectrocolorimeter ①分光比色计②单色盲分光镜spectrocolorimetry 光谱色度学spectrocomparator 光谱比较仪spectrofluorimeter 荧光分光计spectrofluorometer 荧光分光计spectrofluorometry 荧光光谱测定法spectrofluorophotometer 荧光分光光度计spectrogram 光谱图spectrogrph 摄谱仪，光谱仪spectrographic camera 光谱照像机spectrography 摄谱术spectrometer 分光计，光谱计spectrometry 分光术，光谱测定法spectromicroscope 分光显微镜spectromonitor 分光监视器spectrophotometer 分光光度计，分光比色计spectrophotometer cell 分光光度计比色皿spectrophotometry 分光光度测定法spectropolarimeter 分光偏振计，旋光分光计spectropyrheliometer 日射光谱仪spectroradiometer 分光辐射谱仪spectroscope 分光镜，分光仪spectroscopy 分光镜检查spectrum 光谱，光系，谱specular image 镜像speculum ①窥器，张开器②窥镜speculum forceps 窥器钳speech 语言，演说speech amplifier 音频放大器speech coder 语言编码器speech recognizing machine 语言识别机speed 速率，速度，转数speed autoclave 快速灭菌器speedometer 示速器，里程计spermatangium 精子器SPF (spectrophotofluorometer) 荧光分光光度计sp. gr. (specific gravity) 比重spheno- 楔形，蝶骨sphenoidal rasp 蝶骨锉sphenoid sinus canula 蝶窦套管sphenoid sinus curette 蝶窦刮匙sphenoid sinus rongeur 鼻蝶窦咬骨钳sphenometer （楔形）骨片测量器sphenotribe 碎颅器sphere 球体，区域，范围，界sphere introducer 眼球置入器spherical aberration 球面像差spherical lens 球面镜片spherical projection perimeter 球形投影视野计spherocylinder 球柱透镜spheroid ①球形的②球形体spherometer 球径计sphincter 括约肌sphincteroscope 肛门括约肌镜sphincteroscopy 肛门括约肌匀检查sphincterotome 括约肌切开器sphygmo- 脉，脉搏sphygmobologram 脉能图，胸压曲线sphygmobolograph 脉能描记器sphygmobolometer 脉能描记器，脉压计sphygmobolometry 脉能描记法，脉压测量术sphygmocardiogram 脉搏心动图sphygmocardiograph 脉搏心动描记器sphygmocardioscope 脉搏心音描记器sphygmochronograph 脉搏自动描记器sphygmochronography 脉搏自动描记法sphygmodynamometer 脉搏力计sphygmodynamometry 脉搏测量法sphygmogram 脉搏图，脉搏曲线sphygmograph 脉搏描记器，脉搏计sphygmograph transducer 脉搏计换能器sphygmography 脉搏描记法sphygmoid 脉样的，脉搏状的sphygmology 脉学，脉搏学sphygmomanometer 血压计sphygmomanometroscope 复式血压计sphygmomanometry 血压测量法。

毕业设计论文塑料注射成型

Modeling of morphology evolution in the injection moldingprocess of thermoplastic polymersR.Pantani,I.Coccorullo,V.Speranza,G.Titomanlio* Department of Chemical and Food Engineering,University of Salerno,via Ponte don Melillo,I-84084Fisciano(Salerno),Italy Received13May2005;received in revised form30August2005;accepted12September2005AbstractA thorough analysis of the effect of operative conditions of injection molding process on the morphology distribution inside the obtained moldings is performed,with particular reference to semi-crystalline polymers.The paper is divided into two parts:in the ﬁrst part,the state of the art on the subject is outlined and discussed;in the second part,an example of the characterization required for a satisfactorily understanding and description of the phenomena is presented,starting from material characterization,passing through the monitoring of the process cycle and arriving to a deep analysis of morphology distribution inside the moldings.In particular,fully characterized injection molding tests are presented using an isotactic polypropylene,previously carefully characterized as far as most of properties of interest.The effects of both injectionﬂow rate and mold temperature are analyzed.The resulting moldings morphology(in terms of distribution of crystallinity degree,molecular orientation and crystals structure and dimensions)are analyzed by adopting different experimental techniques(optical,electronic and atomic force microscopy,IR and WAXS analysis).Final morphological characteristics of the samples are compared with the predictions of a simulation code developed at University of Salerno for the simulation of the injection molding process.q2005Elsevier Ltd.All rights reserved.Keywords:Injection molding;Crystallization kinetics;Morphology;Modeling;Isotactic polypropyleneContents1.Introduction (1186)1.1.Morphology distribution in injection molded iPP parts:state of the art (1189)1.1.1.Modeling of the injection molding process (1190)1.1.2.Modeling of the crystallization kinetics (1190)1.1.3.Modeling of the morphology evolution (1191)1.1.4.Modeling of the effect of crystallinity on rheology (1192)1.1.5.Modeling of the molecular orientation (1193)1.1.6.Modeling of theﬂow-induced crystallization (1195)ments on the state of the art (1197)2.Material and characterization (1198)2.1.PVT description (1198)*Corresponding author.Tel.:C39089964152;fax:C39089964057.E-mail address:gtitomanlio@unisa.it(G.Titomanlio).2.2.Quiescent crystallization kinetics (1198)2.3.Viscosity (1199)2.4.Viscoelastic behavior (1200)3.Injection molding tests and analysis of the moldings (1200)3.1.Injection molding tests and sample preparation (1200)3.2.Microscopy (1202)3.2.1.Optical microscopy (1202)3.2.2.SEM and AFM analysis (1202)3.3.Distribution of crystallinity (1202)3.3.1.IR analysis (1202)3.3.2.X-ray analysis (1203)3.4.Distribution of molecular orientation (1203)4.Analysis of experimental results (1203)4.1.Injection molding tests (1203)4.2.Morphology distribution along thickness direction (1204)4.2.1.Optical microscopy (1204)4.2.2.SEM and AFM analysis (1204)4.3.Morphology distribution alongﬂow direction (1208)4.4.Distribution of crystallinity (1210)4.4.1.Distribution of crystallinity along thickness direction (1210)4.4.2.Crystallinity distribution alongﬂow direction (1212)4.5.Distribution of molecular orientation (1212)4.5.1.Orientation along thickness direction (1212)4.5.2.Orientation alongﬂow direction (1213)4.5.3.Direction of orientation (1214)5.Simulation (1214)5.1.Pressure curves (1215)5.2.Morphology distribution (1215)5.3.Molecular orientation (1216)5.3.1.Molecular orientation distribution along thickness direction (1216)5.3.2.Molecular orientation distribution alongﬂow direction (1216)5.3.3.Direction of orientation (1217)5.4.Crystallinity distribution (1217)6.Conclusions (1217)References (1219)1.IntroductionInjection molding is one of the most widely employed methods for manufacturing polymeric products.Three main steps are recognized in the molding:ﬁlling,packing/holding and cooling.During theﬁlling stage,a hot polymer melt rapidlyﬁlls a cold mold reproducing a cavity of the desired product shape. During the packing/holding stage,the pressure is raised and extra material is forced into the mold to compensate for the effects that both temperature decrease and crystallinity development determine on density during solidiﬁcation.The cooling stage starts at the solidiﬁcation of a thin section at cavity entrance (gate),starting from that instant no more material can enter or exit from the mold impression and holding pressure can be released.When the solid layer on the mold surface reaches a thickness sufﬁcient to assure required rigidity,the product is ejected from the mold.Due to the thermomechanical history experienced by the polymer during processing,macromolecules in injection-molded objects present a local order.This order is referred to as‘morphology’which literally means‘the study of the form’where form stands for the shape and arrangement of parts of the object.When referred to polymers,the word morphology is adopted to indicate:–crystallinity,which is the relative volume occupied by each of the crystalline phases,including mesophases;–dimensions,shape,distribution and orientation of the crystallites;–orientation of amorphous phase.R.Pantani et al./Prog.Polym.Sci.30(2005)1185–1222 1186R.Pantani et al./Prog.Polym.Sci.30(2005)1185–12221187Apart from the scientiﬁc interest in understandingthe mechanisms leading to different order levels inside a polymer,the great technological importance of morphology relies on the fact that polymer character-istics (above all mechanical,but also optical,electrical,transport and chemical)are to a great extent affected by morphology.For instance,crystallinity has a pro-nounced effect on the mechanical properties of the bulk material since crystals are generally stiffer than amorphous material,and also orientation induces anisotropy and other changes in mechanical properties.In this work,a thorough analysis of the effect of injection molding operative conditions on morphology distribution in moldings with particular reference to crystalline materials is performed.The aim of the paper is twofold:ﬁrst,to outline the state of the art on the subject;second,to present an example of the characterization required for asatisfactorilyR.Pantani et al./Prog.Polym.Sci.30(2005)1185–12221188understanding and description of the phenomena, starting from material description,passing through the monitoring of the process cycle and arriving to a deep analysis of morphology distribution inside the mold-ings.To these purposes,fully characterized injection molding tests were performed using an isotactic polypropylene,previously carefully characterized as far as most of properties of interest,in particular quiescent nucleation density,spherulitic growth rate and rheological properties(viscosity and relaxation time)were determined.The resulting moldings mor-phology(in terms of distribution of crystallinity degree, molecular orientation and crystals structure and dimensions)was analyzed by adopting different experimental techniques(optical,electronic and atomic force microscopy,IR and WAXS analysis).Final morphological characteristics of the samples were compared with the predictions of a simulation code developed at University of Salerno for the simulation of the injection molding process.The effects of both injectionﬂow rate and mold temperature were analyzed.1.1.Morphology distribution in injection molded iPP parts:state of the artFrom many experimental observations,it is shown that a highly oriented lamellar crystallite microstructure, usually referred to as‘skin layer’forms close to the surface of injection molded articles of semi-crystalline polymers.Far from the wall,the melt is allowed to crystallize three dimensionally to form spherulitic structures.Relative dimensions and morphology of both skin and core layers are dependent on local thermo-mechanical history,which is characterized on the surface by high stress levels,decreasing to very small values toward the core region.As a result,the skin and the core reveal distinct characteristics across the thickness and also along theﬂow path[1].Structural and morphological characterization of the injection molded polypropylene has attracted the interest of researchers in the past three decades.In the early seventies,Kantz et al.[2]studied the morphology of injection molded iPP tensile bars by using optical microscopy and X-ray diffraction.The microscopic results revealed the presence of three distinct crystalline zones on the cross-section:a highly oriented non-spherulitic skin;a shear zone with molecular chains oriented essentially parallel to the injection direction;a spherulitic core with essentially no preferred orientation.The X-ray diffraction studies indicated that the skin layer contains biaxially oriented crystallites due to the biaxial extensionalﬂow at theﬂow front.A similar multilayered morphology was also reported by Menges et al.[3].Later on,Fujiyama et al.[4] investigated the skin–core morphology of injection molded iPP samples using X-ray Small and Wide Angle Scattering techniques,and suggested that the shear region contains shish–kebab structures.The same shish–kebab structure was observed by Wenig and Herzog in the shear region of their molded samples[5].A similar investigation was conducted by Titomanlio and co-workers[6],who analyzed the morphology distribution in injection moldings of iPP. They observed a skin–core morphology distribution with an isotropic spherulitic core,a skin layer characterized by aﬁne crystalline structure and an intermediate layer appearing as a dark band in crossed polarized light,this layer being characterized by high crystallinity.Kalay and Bevis[7]pointed out that,although iPP crystallizes essentially in the a-form,a small amount of b-form can be found in the skin layer and in the shear region.The amount of b-form was found to increase by effect of high shear rates[8].A wide analysis on the effect of processing conditions on the morphology of injection molded iPP was conducted by Viana et al.[9]and,more recently, by Mendoza et al.[10].In particular,Mendoza et al. report that the highest level of crystallinity orientation is found inside the shear zone and that a high level of orientation was also found in the skin layer,with an orientation angle tilted toward the core.It is rather difﬁcult to theoretically establish the relationship between the observed microstructure and processing conditions.Indeed,a model of the injection molding process able to predict morphology distribution in theﬁnal samples is not yet available,even if it would be of enormous strategic importance.This is mainly because a complete understanding of crystallization kinetics in processing conditions(high cooling rates and pressures,strong and complexﬂowﬁelds)has not yet been reached.In this section,the most relevant aspects for process modeling and morphology development are identiﬁed. In particular,a successful path leading to a reliable description of morphology evolution during polymer processing should necessarily pass through:–a good description of morphology evolution under quiescent conditions(accounting all competing crystallization processes),including the range of cooling rates characteristic of processing operations (from1to10008C/s);R.Pantani et al./Prog.Polym.Sci.30(2005)1185–12221189–a description capturing the main features of melt morphology(orientation and stretch)evolution under processing conditions;–a good coupling of the two(quiescent crystallization and orientation)in order to capture the effect of crystallinity on viscosity and the effect ofﬂow on crystallization kinetics.The points listed above outline the strategy to be followed in order to achieve the basic understanding for a satisfactory description of morphology evolution during all polymer processing operations.In the following,the state of art for each of those points will be analyzed in a dedicated section.1.1.1.Modeling of the injection molding processTheﬁrst step in the prediction of the morphology distribution within injection moldings is obviously the thermo-mechanical simulation of the process.Much of the efforts in the past were focused on the prediction of pressure and temperature evolution during the process and on the prediction of the melt front advancement [11–15].The simulation of injection molding involves the simultaneous solution of the mass,energy and momentum balance equations.Theﬂuid is non-New-tonian(and viscoelastic)with all parameters dependent upon temperature,pressure,crystallinity,which are all function of pressibility cannot be neglected as theﬂow during the packing/holding step is determined by density changes due to temperature, pressure and crystallinity evolution.Indeed,apart from some attempts to introduce a full 3D approach[16–19],the analysis is currently still often restricted to the Hele–Shaw(or thinﬁlm) approximation,which is warranted by the fact that most injection molded parts have the characteristic of being thin.Furthermore,it is recognized that the viscoelastic behavior of the polymer only marginally inﬂuences theﬂow kinematics[20–22]thus the melt is normally considered as a non-Newtonian viscousﬂuid for the description of pressure and velocity gradients evolution.Some examples of adopting a viscoelastic constitutive equation in the momentum balance equations are found in the literature[23],but the improvements in accuracy do not justify a considerable extension of computational effort.It has to be mentioned that the analysis of some features of kinematics and temperature gradients affecting the description of morphology need a more accurate description with respect to the analysis of pressure distributions.Some aspects of the process which were often neglected and may have a critical importance are the description of the heat transfer at polymer–mold interface[24–26]and of the effect of mold deformation[24,27,28].Another aspect of particular interest to the develop-ment of morphology is the fountainﬂow[29–32], which is often neglected being restricted to a rather small region at theﬂow front and close to the mold walls.1.1.2.Modeling of the crystallization kineticsIt is obvious that the description of crystallization kinetics is necessary if theﬁnal morphology of the molded object wants to be described.Also,the development of a crystalline degree during the process inﬂuences the evolution of all material properties like density and,above all,viscosity(see below).Further-more,crystallization kinetics enters explicitly in the generation term of the energy balance,through the latent heat of crystallization[26,33].It is therefore clear that the crystallinity degree is not only a result of simulation but also(and above all)a phenomenon to be kept into account in each step of process modeling.In spite of its dramatic inﬂuence on the process,the efforts to simulate the injection molding of semi-crystalline polymers are crude in most of the commercial software for processing simulation and rather scarce in the ﬂeur and Kamal[34],Papatanasiu[35], Titomanlio et al.[15],Han and Wang[36],Ito et al.[37],Manzione[38],Guo and Isayev[26],and Hieber [25]adopted the following equation(Kolmogoroff–Avrami–Evans,KAE)to predict the development of crystallinityd xd tZð1K xÞd d cd t(1)where x is the relative degree of crystallization;d c is the undisturbed volume fraction of the crystals(if no impingement would occur).A signiﬁcant improvement in the prediction of crystallinity development was introduced by Titoman-lio and co-workers[39]who kept into account the possibility of the formation of different crystalline phases.This was done by assuming a parallel of several non-interacting kinetic processes competing for the available amorphous volume.The evolution of each phase can thus be described byd x id tZð1K xÞd d c id t(2)where the subscript i stands for a particular phase,x i is the relative degree of crystallization,x ZPix i and d c iR.Pantani et al./Prog.Polym.Sci.30(2005)1185–1222 1190is the expectancy of volume fraction of each phase if no impingement would occur.Eq.(2)assumes that,for each phase,the probability of the fraction increase of a single crystalline phase is simply the product of the rate of growth of the corresponding undisturbed volume fraction and of the amount of available amorphous fraction.By summing up the phase evolution equations of all phases(Eq.(2))over the index i,and solving the resulting differential equation,one simply obtainsxðtÞZ1K exp½K d cðtÞ (3)where d c Z Pid c i and Eq.(1)is recovered.It was shown by Coccorullo et al.[40]with reference to an iPP,that the description of the kinetic competition between phases is crucial to a reliable prediction of solidiﬁed structures:indeed,it is not possible to describe iPP crystallization kinetics in the range of cooling rates of interest for processing(i.e.up to several hundreds of8C/s)if the mesomorphic phase is neglected:in the cooling rate range10–1008C/s, spherulite crystals in the a-phase are overcome by the formation of the mesophase.Furthermore,it has been found that in some conditions(mainly at pressures higher than100MPa,and low cooling rates),the g-phase can also form[41].In spite of this,the presence of different crystalline phases is usually neglected in the literature,essentially because the range of cooling rates investigated for characterization falls in the DSC range (well lower than typical cooling rates of interest for the process)and only one crystalline phase is formed for iPP at low cooling rates.It has to be noticed that for iPP,which presents a T g well lower than ambient temperature,high values of crystallinity degree are always found in solids which passed through ambient temperature,and the cooling rate can only determine which crystalline phase forms, roughly a-phase at low cooling rates(below about 508C/s)and mesomorphic phase at higher cooling rates.The most widespread approach to the description of kinetic constant is the isokinetic approach introduced by Nakamura et al.According to this model,d c in Eq.(1)is calculated asd cðtÞZ ln2ðt0KðTðsÞÞd s2 435n(4)where K is the kinetic constant and n is the so-called Avrami index.When introduced as in Eq.(4),the reciprocal of the kinetic constant is a characteristic time for crystallization,namely the crystallization half-time, t05.If a polymer is cooled through the crystallization temperature,crystallization takes place at the tempera-ture at which crystallization half-time is of the order of characteristic cooling time t q deﬁned ast q Z D T=q(5) where q is the cooling rate and D T is a temperature interval over which the crystallization kinetic constant changes of at least one order of magnitude.The temperature dependence of the kinetic constant is modeled using some analytical function which,in the simplest approach,is described by a Gaussian shaped curve:KðTÞZ K0exp K4ln2ðT K T maxÞ2D2(6)The following Hoffman–Lauritzen expression[42] is also commonly adopted:K½TðtÞ Z K0exp KUÃR$ðTðtÞK T NÞ!exp KKÃ$ðTðtÞC T mÞ2TðtÞ2$ðT m K TðtÞÞð7ÞBoth equations describe a bell shaped curve with a maximum which for Eq.(6)is located at T Z T max and for Eq.(7)lies at a temperature between T m(the melting temperature)and T N(which is classically assumed to be 308C below the glass transition temperature).Accord-ing to Eq.(7),the kinetic constant is exactly zero at T Z T m and at T Z T N,whereas Eq.(6)describes a reduction of several orders of magnitude when the temperature departs from T max of a value higher than2D.It is worth mentioning that only three parameters are needed for Eq.(6),whereas Eq.(7)needs the deﬁnition ofﬁve parameters.Some authors[43,44]couple the above equations with the so-called‘induction time’,which can be deﬁned as the time the crystallization process starts, when the temperature is below the equilibrium melting temperature.It is normally described as[45]Dt indDtZðT0m K TÞat m(8)where t m,T0m and a are material constants.It should be mentioned that it has been found[46,47]that there is no need to explicitly incorporate an induction time when the modeling is based upon the KAE equation(Eq.(1)).1.1.3.Modeling of the morphology evolutionDespite of the fact that the approaches based on Eq.(4)do represent a signiﬁcant step toward the descriptionR.Pantani et al./Prog.Polym.Sci.30(2005)1185–12221191of morphology,it has often been pointed out in the literature that the isokinetic approach on which Nakamura’s equation (Eq.(4))is based does not describe details of structure formation [48].For instance,the well-known experience that,with many polymers,the number of spherulites in the ﬁnal solid sample increases strongly with increasing cooling rate,is indeed not taken into account by this approach.Furthermore,Eq.(4)describes an increase of crystal-linity (at constant temperature)depending only on the current value of crystallinity degree itself,whereas it is expected that the crystallization rate should depend also on the number of crystalline entities present in the material.These limits are overcome by considering the crystallization phenomenon as the consequence of nucleation and growth.Kolmogoroff’s model [49],which describes crystallinity evolution accounting of the number of nuclei per unit volume and spherulitic growth rate can then be applied.In this case,d c in Eq.(1)is described asd ðt ÞZ C m ðt 0d N ðs Þd s$ðt sG ðu Þd u 2435nd s (9)where C m is a shape factor (C 3Z 4/3p ,for spherical growth),G (T (t ))is the linear growth rate,and N (T (t ))is the nucleation density.The following Hoffman–Lauritzen expression is normally adopted for the growth rateG ½T ðt Þ Z G 0exp KUR $ðT ðt ÞK T N Þ!exp K K g $ðT ðt ÞC T m Þ2T ðt Þ2$ðT m K T ðt ÞÞð10ÞEqs.(7)and (10)have the same form,however the values of the constants are different.The nucleation mechanism can be either homo-geneous or heterogeneous.In the case of heterogeneous nucleation,two equations are reported in the literature,both describing the nucleation density as a function of temperature [37,50]:N ðT ðt ÞÞZ N 0exp ½j $ðT m K T ðt ÞÞ (11)N ðT ðt ÞÞZ N 0exp K 3$T mT ðt ÞðT m K T ðt ÞÞ(12)In the case of homogeneous nucleation,the nucleation rate rather than the nucleation density is function of temperature,and a Hoffman–Lauritzen expression isadoptedd N ðT ðt ÞÞd t Z N 0exp K C 1ðT ðt ÞK T N Þ!exp KC 2$ðT ðt ÞC T m ÞT ðt Þ$ðT m K T ðt ÞÞð13ÞConcentration of nucleating particles is usually quite signiﬁcant in commercial polymers,and thus hetero-geneous nucleation becomes the dominant mechanism.When Kolmogoroff’s approach is followed,the number N a of active nuclei at the end of the crystal-lization process can be calculated as [48]N a ;final Zðt final 0d N ½T ðs Þd sð1K x ðs ÞÞd s (14)and the average dimension of crystalline structures can be attained by geometrical considerations.Pantani et al.[51]and Zuidema et al.[22]exploited this method to describe the distribution of crystallinity and the ﬁnal average radius of the spherulites in injection moldings of polypropylene;in particular,they adopted the following equationR Z ﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃ3x a ;final 4p N a ;final 3s (15)A different approach is also present in the literature,somehow halfway between Nakamura’s and Kolmo-goroff’s models:the growth rate (G )and the kinetic constant (K )are described independently,and the number of active nuclei (and consequently the average dimensions of crystalline entities)can be obtained by coupling Eqs.(4)and (9)asN a ðT ÞZ 3ln 24p K ðT ÞG ðT Þ 3(16)where heterogeneous nucleation and spherical growth is assumed (Avrami’s index Z 3).Guo et al.[43]adopted this approach to describe the dimensions of spherulites in injection moldings of polypropylene.1.1.4.Modeling of the effect of crystallinity on rheology As mentioned above,crystallization has a dramatic inﬂuence on material viscosity.This phenomenon must obviously be taken into account and,indeed,the solidiﬁcation of a semi-crystalline material is essen-tially caused by crystallization rather than by tempera-ture in normal processing conditions.Despite of the importance of the subject,the relevant literature on the effect of crystallinity on viscosity isR.Pantani et al./Prog.Polym.Sci.30(2005)1185–12221192rather scarce.This might be due to the difﬁculties in measuring simultaneously rheological properties and crystallinity evolution during the same tests.Apart from some attempts to obtain simultaneous measure-ments of crystallinity and viscosity by special setups [52,53],more often viscosity and crystallinity are measured during separate tests having the same thermal history,thus greatly simplifying the experimental approach.Nevertheless,very few works can be retrieved in the literature in which(shear or complex) viscosity can be somehow linked to a crystallinity development.This is the case of Winter and co-workers [54],Vleeshouwers and Meijer[55](crystallinity evolution can be drawn from Swartjes[56]),Boutahar et al.[57],Titomanlio et al.[15],Han and Wang[36], Floudas et al.[58],Wassner and Maier[59],Pantani et al.[60],Pogodina et al.[61],Acierno and Grizzuti[62].All the authors essentially agree that melt viscosity experiences an abrupt increase when crystallinity degree reaches a certain‘critical’value,x c[15]. However,little agreement is found in the literature on the value of this critical crystallinity degree:assuming that x c is reached when the viscosity increases of one order of magnitude with respect to the molten state,it is found in the literature that,for iPP,x c ranges from a value of a few percent[15,62,60,58]up to values of20–30%[58,61]or even higher than40%[59,54,57].Some studies are also reported on the secondary effects of relevant variables such as temperature or shear rate(or frequency)on the dependence of crystallinity on viscosity.As for the effect of temperature,Titomanlio[15]found for an iPP that the increase of viscosity for the same crystallinity degree was higher at lower temperatures,whereas Winter[63] reports the opposite trend for a thermoplastic elasto-meric polypropylene.As for the effect of shear rate,a general agreement is found in the literature that the increase of viscosity for the same crystallinity degree is lower at higher deformation rates[62,61,57].Essentially,the equations adopted to describe the effect of crystallinity on viscosity of polymers can be grouped into two main categories:–equations based on suspensions theories(for a review,see[64]or[65]);–empirical equations.Some of the equations adopted in the literature with regard to polymer processing are summarized in Table1.Apart from Eq.(17)adopted by Katayama and Yoon [66],all equations predict a sharp increase of viscosity on increasing crystallinity,sometimes reaching inﬁnite (Eqs.(18)and(21)).All authors consider that the relevant variable is the volume occupied by crystalline entities(i.e.x),even if the dimensions of the crystals should reasonably have an effect.1.1.5.Modeling of the molecular orientationOne of the most challenging problems to present day polymer science regards the reliable prediction of molecular orientation during transformation processes. Indeed,although pressure and velocity distribution during injection molding can be satisfactorily described by viscous models,details of the viscoelastic nature of the polymer need to be accounted for in the descriptionTable1List of the most used equations to describe the effect of crystallinity on viscosityEquation Author Derivation Parameters h=h0Z1C a0x(17)Katayama[66]Suspensions a Z99h=h0Z1=ðx K x cÞa0(18)Ziabicki[67]Empirical x c Z0.1h=h0Z1C a1expðK a2=x a3Þ(19)Titomanlio[15],also adopted byGuo[68]and Hieber[25]Empiricalh=h0Z expða1x a2Þ(20)Shimizu[69],also adopted byZuidema[22]and Hieber[25]Empiricalh=h0Z1Cðx=a1Þa2=ð1Kðx=a1Þa2Þ(21)Tanner[70]Empirical,basedon suspensionsa1Z0.44for compact crystallitesa1Z0.68for spherical crystallitesh=h0Z expða1x C a2x2Þ(22)Han[36]Empiricalh=h0Z1C a1x C a2x2(23)Tanner[71]Empirical a1Z0.54,a2Z4,x!0.4h=h0Zð1K x=a0ÞK2(24)Metzner[65],also adopted byTanner[70]Suspensions a Z0.68for smooth spheresR.Pantani et al./Prog.Polym.Sci.30(2005)1185–12221193。

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3. Data Processing
Atmospherically induced phase ﬂuctuations distort incoming plane wave-fronts from the distant objects which reach the entrance pupil of telescope with patches of random excursions in phase. Such phase distortions restrict the eﬀective angular resolution of most telescopes to 1 second of arc or worse. Speckle interferometry (Labeyrie, 1970) recovers the diﬀraction limited spatial Fourier spectrum and image features of the object intensity distribution from a series of short-exposure (< 20 m sec.) images. Schemes like Knox-Thompson algorithm (Knox-Thompson, 1974), triple correlation (Lohmann et al., 1983) have been successfully employed to restore the Fourier phase of an extended object. All these schemes require statistical treatment of a large number of images. Often, it may not be possible to record a large number of images within the time interval over which the statistics of the atmospheric turbulence remains stationary. There are a number of schemes, viz., Maximum Entropy Method (Jaynes, 1982), CLEAN algorithm (Hogbom, 1974) and Blind Iterative Deconvolution (BID) technique (Ayers and Dainty, 1988) being applied to restore the image using some prior information about the image. Here, we employed a version of BID developed by P. Nisenson (Nisenson, 1991), on degraded images of Jupiter.
1Indian Institute of Astrophysics, Bangalore 560034, India 2Astronomy Department, Osmania University, Hyderabad 500007, India
Abstract Speckle interferometric technique has been used to obtain a series of short exposure images of the collision of comet Shoemaker-Levy 9 with Jupiter during the period of July 17-24, 1994 using the Nasmyth focus of 1.2 meter telescope of Japal-Rangapur Observatory, Hyderabad. The technique of Blind Iterative Deconvolution (BID) was used to remove the atmospherically induced point spread function (PSF) from these images to obtain diﬀraction limited informations of the impact sites on Jupiter.
2
In this technique (see Bates and McDonnell, 1986), the iterative loop is repeated enforcing image-domain and Fourier-domain constraints until two images are found that produce the input image when convolved together. The imagedomain constraint of non-negativity is generally used in iterative algorithms associated with optical processing to ﬁnd eﬀective supports of the object and or point spread function (PSF) from a speckle-gram. Here, the Weiner ﬁlter was used to estimate one function from an initial guess of the PSF.
1
2. Observations
The image scale at the Nasmyth focus (f/13.7) of 1.2 meter telescope of JRO, was enlarged by a Barlow lens arrangement (Saha et al., 1987, Chinnappan et al., 1991). The set up was modiﬁed to suit to requirement of sampling 0.11 arc sec/pixel of the CCD (at 0.55 µ) which is essentially the diﬀraction limit of the said telescope. A set of 3 ﬁlters were used to image Jupiter, viz.,: (i) centered at 5500 ˚A, with FWHM of 300 ˚A, (ii) centered at 6110 ˚A, with FWHM of 99 ˚A, and (iii) RG9 with a lower wavelength cut-oﬀ at 8000 ˚A.
arXiv:astro-ph/9910510v1 28 Octometric observations of the collision of comet Shoemaker-Levy 9 with Jupiter
S K Saha1, R Rajamohon1, P Vivekananda Rao2, G Som Sunder2, R Swaminathan2 and B Lokanadham2
A 1024×1024 pixel water cooled CCD with a pixel size 22µ was used as a detector. 50 speckle-grams were sequentially recorded (each of 100 m sec exposure) in each of the 3 ﬁlters. The exposure time was chosen to obtain a good signalto noise ratio. Since the smearing due to the equatorial rotation of Jupiter is about 0.15 arc sec/min., one can aﬀord to accumulate speckle-grams for 2-3 minutes, if one expected to attain a resolution of 0.5 arc sec. In this experiment, we have recorded 10 speckle-grams/min. Therefore, 20-30 frames with good enough signal-to-noise ratio at the desired spatial frequencies are required to perform speckle reconstruction. 600 images were recorded on July 17, 1994 soon after the fragment E of the Comet SL-9 collided with Jupiter. On July 24, 1994, 80 more images were recorded. A liquid nitrogen cooled 512×512 CCD was used to record 3 images of Jupiter in integrated light on July 22, 1994.
Key words: Speckle Imaging, Image Reconstruction, Jupiter, Shoemaker-Levy 9
1. Introduction
The impact of the collision of the comet Shoemaker-Levy 9 (1993e) with the gaseous planet Jupiter during the period 16th.-22nd. July, 1994, has been observed extensively worldwide, as well as from the Hubble space Telescope. Several observatories in India too had planned observations of the crash phenomena starting from the observations in the visible part of the electro magnetic spectrum to the radio frequencies (Cowsik, 1994). As a part of the programmes, we had developed an interferometer to record the images of the collision of the fragments of Comet Shoemaker-Levy 9 (SL 9) with Jupiter during the period 17-24th. July, 1994, with a goal of achieving features with a resolution of 0.3-0.5 arc sec., in the optical band, using 1.2 meter telescope at Japal-Rangapur Observatory (JRO), Osmania University, Hyderabad. Though, monsoon condition prevailed over large part of the country, we were able to record more than 600 images of the entire planetary disk of Jupiter during the said period. In this paper, we describe the observational technique using interferometer, as well as the image processing technique used to restore the degraded images of Jupiter.

Speckle interferometric observations of the collision of comet Shoemaker-Levy 9 with Jupite

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