下载文档原格式
the final of catal pol concentrati on were 0125,015,1,215,5mg ·mL -1,res pectively .The cortical neur on was identified by NF 2200antigen and its survival activity detected byM TT assay .The axonal gr owth of cultured cortical neur on were observed by inverted m icr os 2copy with m icr ometer .Result:I m munocyt oche m istry de monstrated more than 95%of the p ri m ary cultured cortical neur ons were posi 2tive for NF 2200antigen,which indicated the cultured cells were neur ons .Neur ons survived gr owing on the concentrati on of 0125,015,1,215,5mg ·mL -1.Compared with blank and 1mg ·mL -1citicoline gr oup,neur ons survival rates were not statistical significantdifference .However,it de monstrated that catal pol significantly p r omoted axonal gr owth fr om 125mg ·mL-1(P <0105).I nterestedly,compared with the dose of 215mg ·mL -1,axonal gr owth was shorter at the dose of 5mg ·mL-1,and 215mg ·mL -1catal pol showedthe str ongest p r omoti on effect .Conclusi on:The catal pol can enhance cortical neur on axonal gr owth,but not p r omote cortical neur onsurvival .[Key words] catal pol;cortical neur ons;p ri m ary culture;axon length[责任编辑 古云侠]鹅绒藤对小鼠镇静催眠作用的研究彭晓东3,闫乾顺,王 锐,杨卫东,彭建中(宁夏医学院,宁夏银川750004)[摘要] 目的:研究鹅绒藤全草水提物和氯仿提取物对小鼠的镇静催眠作用。
PM2.5是大气颗粒物的一种，空气动力学直径≤2.5μm ，能够透过肺泡进入血液循环系统诱发呼吸道感染、心血管疾病、肺癌、免疫系统衰竭等多种全身性疾病，严重危害人体健康［1-5］。
越来越多的证据证明，孕期PM2.5暴露可引起胎盘结构异常和功能改变，诱发早产、子痫前期、复发性流产等不良妊娠结局［6-9］。
然而，关于PM2.5对妊娠结局和子代发育影响的研究目前多集Metformin ameliorates PM2.5-induced functional impairment of placental trophoblasts by inhibiting ferroptosisLI Shuxian 1,YU Shuping 2,MU Yaming 2,WANG Kai 2,LIU Yu 1,ZHANG Meihua 11Key Laboratory of Maternal &Fetal Medicine of National Health Commission of China ，Shandong Provincial Maternal and Child HealthCare Hospital Affiliated to Qingdao University,Jinan 250014,China;2Shandong Second Medical University,Weifang 261053,China摘要：目的探究PM2.5损伤胎盘滋养细胞导致不良妊娠结局的作用机制及二甲双胍的挽救作用。
方法将16只孕鼠随机分为空白组（n =8），PM2.5染毒组（n =8），两组分别在妊娠1.5、7.5、12.5d 通过气管滴注PBS 和PM2.5悬浮液。
观察PM2.5对孕鼠妊娠结局的影响，并通过HE 染色观察小鼠胎盘病理结构，检测胎盘组织铁死亡相关指标。
体外构建PM2.5暴露的人类胎盘滋养细胞系HTR8/SVneo 细胞染毒模型，利用CCK8实验检测细胞活性；利用EDU 染色检测细胞增殖能力；利用划痕实验检测细胞迁移能力；利用Transwell 实验检测细胞侵袭能力；利用成管实验检测细胞管生成能力；通过ELISA 和Western blotting 等方法分析铁死亡相关指标的表达。
海风藤提取物对胶原诱导性关节炎大鼠的影响目的：研究海风藤正丁醇提取物对胶原诱导性关节炎大鼠滑膜组织中NF-κB、IκB和IκK的影响，探讨其治疗作用机制。
方法：通过建立胶原诱导性关节炎（CIA）大鼠模型，观察大鼠足趾肿胀度的变化，蛋白印迹法检测大鼠踝关节滑膜组织中NF-κB、IκB和IκK的表达水平。
结果：海风藤正丁醇提取物能改善大鼠活动减少、精神不佳等一般状态，下调滑膜组织中NF-κB、IκK的表达及上调滑膜组织中IκB的表达。
结论：海风藤正丁醇提取物对类风湿性关节炎有一定的治疗作用，其机理与调节滑膜组织中NF-κB、IκB和IκK的表达水平有关。
标签：海风藤；胶原诱导性关节炎；NF-κB；IκB；IκKAbstract：Objective To investigate the therapeutic effect of Piperis kadsurae caulis extraction on collagen-induced rheumatoid arthritis rats，and its effects on NF-κB，IκB and IκK in synovial tiss ue，and to explore its therapeutic mechanism.Methods CIA rat model was induced by injecting bovine type II collagen.The swelling level of paw was observed and the expression of NF-κB，IKB and IκK were evaluated by Western blotting.Results The ethyl acetate extraces of Piperis kadsurae caulis could inhibit the paw swelling and down-regulate the expression of NF-κB，IκB and IκK.Conclusion The ethyl acetate extraces of Piperis kadsurae caulis have certain therapeutic on rheumatoid arthritis by reducing the expression of NF-κB，IκB and IκK in synovial tissue.Keywords：Piperis kadsurae caulis；collagen-induced rheumatoid arthritis；NF-κB；IκB；IκK海风藤是胡椒科植物风藤（Piper kadsura （Choisy）Owchi.）的干燥藤茎，辛、苦，微温，具有祛风湿、通经络、止痹通等功效[1]。
黎琳莹，林以琳，温耀升，等. 异硫氰酸烯丙酯对产气荚膜梭菌的抑菌作用及在熟猪肉糜中的应用[J]. 食品工业科技，2023，44（23）：127−133. doi: 10.13386/j.issn1002-0306.2023020200LI Linying, LIN Yilin, WEN Yaosheng, et al. Inhibitory Effect of Allyl Isothiocyanate on Clostridium perfringens and Its Application of Cooked Pork[J]. Science and Technology of Food Industry, 2023, 44(23): 127−133. (in Chinese with English abstract). doi:10.13386/j.issn1002-0306.2023020200· 生物工程 ·异硫氰酸烯丙酯对产气荚膜梭菌的抑菌作用及在熟猪肉糜中的应用黎琳莹1，林以琳1，温耀升2，廖彩虎2, *，余以刚1,*（1.华南理工大学食品科学与工程学院，广东广州 510640；2.韶关学院英东食品学院，广东韶关 512005）摘 要：本文旨在研究异硫氰酸烯丙酯（Allyl isothiocyanate ，AITC ）对产气荚膜梭菌（Clostridium perfringens ，C.perfringens ）的抑菌效果及作用机制。
首先，通过测定最小抑菌浓度（Minimum inhibition concentration ，MIC ）、绘制生长曲线评估AITC 对C. perfringens 的抑菌效果，并采用扫描电镜观察细胞形态、碘化丙啶染色实验测定细胞膜完整性，评估AITC 对C. perfringens 细胞膜的影响；进一步通过SDS-PAGE 图谱分析和ATP 酶活力测定研究AITC 对C. perfringens 细胞代谢的影响；最后，研究了AITC 对熟猪肉糜中C. perfringens 的抑制效果。
中 国 药 科 大 学 学 报Jou rnal of Ch ina Pharm aceu tical U n iversity 1996,27(6):345～349促进剂对青蒿琥酯体外经皮渗透的影响α孙国庆 平其能 厉 程(中国药科大学药剂学教研室,南京210009)摘 要 以离体小鼠皮肤为渗透屏障,采用预处理法研究了多种促进剂对青蒿琥酯经皮渗透的增强作用,结果表明,药物经皮渗透符合零级动力学过程,几种渗透促进剂的促进作用大小依次为:薄荷油>氮酮>氮酮2丙二醇(1∶1)>桉叶油>松节油>油酸>桉叶油2丙二醇(1∶1)>二甲基亚砜>吐温280>二甲基甲酰胺。
各促进剂在实际处方中的作用效能有所下降,但作用大小次序不变。
氮酮的促渗作用呈现浓度依赖性,其最佳浓度为3%。
关键词 青蒿琥酯;渗透促进剂;透皮速率 青蒿琥酯(artesunate)是我国科学工作者创制的具有倍半萜内酯结构的新型抗疟药青蒿素的衍生物,其化学名为二氢青蒿素2 102Α2琥珀酸单酯,具有较青蒿素更高的抗疟活性,尤其对恶性疟、脑疟、间日疟及抗氯喹的疟原虫具有良好的治疗效果。
青蒿琥酯一般采用口服、肌注及静注方式给药,由于其体内代谢迅速,消除半衰期很短,有肝脏首过效应,临床需多次给药,才能有效地降低复燃率,给患者带来诸多不便[1]。
长时间维持一定的有效血药浓度对于疟疾的防治、降低复燃率具有十分重要的意义。
根据青蒿琥酯临床治疗的药物动力学特征及药剂学原理,专家估计了青蒿琥酯透皮给药的可能性,周钟鸣等对青蒿素的经皮吸收制剂进行了初步研究,取得了一定的成果[2]。
本实验利用小鼠皮肤为渗透屏障,研究促进剂对青蒿琥酯透皮吸收的促进效果,为创制能长时间维持有效血药浓度,减少给药次数,全面改善抗疟疗效的青蒿琥酯经皮吸收制剂打下基础。
1 实验部分1.1 材料与仪器青蒿琥酯(药用,广西桂林制药厂),油酸、氮酮、松节油、桉叶油、薄荷油、羟丙甲纤维素、聚乙烯吡咯烷酮等均为药用规格,无水乙醇、乙醚、1,22丙二醇均为分析纯。
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。
张冰心，隋静，裴令栋，等. 百里香精油成分对壳聚糖膜结构特性的影响及其迁移机制[J]. 食品工业科技，2023，44（10）：249−255.doi: 10.13386/j.issn1002-0306.2022080217ZHANG Bingxin, SUI Jing, PEI Lingdong, et al. Effect of Thyme Essential Oil Components on the Structure Properties of Chitosan Films and Its Migration Mechanism[J]. Science and Technology of Food Industry, 2023, 44(10): 249−255. (in Chinese with English abstract). doi: 10.13386/j.issn1002-0306.2022080217· 包装与机械 ·百里香精油成分对壳聚糖膜结构特性的影响及其迁移机制张冰心1，隋 静2，裴令栋3，宿玲绮1，彭 勇1,*（1.山东农业大学食品科学与工程学院，山东泰安 271018；2.莱芜职业技术学院，山东济南 250002；3.辰欣药业股份有限公司，山东济宁 272000）摘 要：为探究百里香精油成分百里香酚、芳樟醇和石竹烯从壳聚糖膜中的迁移机制，对其构建的壳聚糖复合膜物理性能、抗菌性能、迁移特性和化学结构进行研究。
结果表明，百里香精油、百里香酚和石竹烯均提高了壳聚糖膜的阻水性，其中石竹烯的水蒸气透过率比对照下降了15.04%，并且，百里香酚和石竹烯也降低了复合膜的膨胀度（下降24.31%和11.64%）和断裂伸长率（下降13.46%和27.88%），但显著（P <0.05）提高了壳聚糖膜的抗菌性，以百里香精油复合膜抗菌效果最好。
所有精油成分均增加了壳聚糖膜的吸热峰温度，提高了复合膜的热稳定性。
鹅绒委陵菜多糖对荷瘤小鼠细胞因子的影响成英;宋九华;刘素君【摘要】[ Objective ] To study the effects of polysaccharides from Potentilla anserine ( PAP) on the levels of interleukin-2 (IL-2) and tumor necrosis factor-α (TNF-α) from peripheral blood. [Method] The mice models with tumor S180 were established and treated with 50, 100 and 200 mg/kg PAP by gastric perfusion, respectively. The inhibition rate ofS180 tumor was measured to investigate the antitumor activity in vivo of PAP. The levels of IL-2 and TNF-a in mice peripheral blood were determined with ELISA. [ Result ] The tumor inhibition rates were 46. 41 % , 52. 29% and 59.48% in different groups treated with 50,100 and 200mg/kg PAP in vivo, respectively. Of these, the inhibition rate of CY andlow-dose PAP was equal to that of medium-and high-dose PAP, significantly higher than that of cyclophosphamide. Three dose groups of PAP could significantly increase the content of IL-2 and TNF-a spleen index. [ Conclusion ] The compound PAP could improve the antitumor activity and immunological function of S180 tumor-bearing mice.%[目的]研究鹅绒委陵菜多糖(PAP)对荷瘤小鼠外周血细胞因子白介素-2(TL-2)和肿瘤坏死因子-α(TNF-α)的影响.[方法]建立肉瘤S180小鼠动物模型,灌胃给予50、100和200mg/kg剂量的PAP,以抑瘤率为指标,考察鹅绒委陵菜多糖的体内抗肿瘤活性,测定其抑瘤率；ELISA法测定荷瘤小鼠血清中白细胞介素-2(IL-2)和肿瘤坏死因子-α(TN-α)的水平.[结果]低、中、高3个剂量的PAP对S180荷瘤小鼠的抑瘤率分别为46.41％、52.29％和59.48％；其中CY和低剂量的多糖组合抑瘤率与中、高剂量的多糖抑瘤率相当,并明显高于单用环磷酰胺组的抑瘤率；低、中、高3个剂量的PAP能明显提高荷瘤小鼠血清中IL-2、TNF-α的水平.[结论]鹅绒委陵菜多糖具有提高荷瘤小鼠细胞免疫的作用.【期刊名称】《安徽农业科学》【年(卷),期】2012(040)009【总页数】3页(P5177-5178,5180)【关键词】鹅绒委陵菜多糖;抗肿瘤;细胞因子【作者】成英;宋九华;刘素君【作者单位】乐山师范学院天然产物研究所,四川乐山614004;乐山师范学院天然产物研究所,四川乐山614004;乐山师范学院天然产物研究所,四川乐山614004【正文语种】中文【中图分类】S567;R284鹅绒委陵菜(Potentilla anserina L)属蔷薇科委陵菜属多年生匍匐草本植物，俗称人参果，又称蕨麻，可食用［1］。
许庆鹏，姜秀杰，张家瑜，等. 冷等离子体联合L-谷氨酸与盐胁迫对红小豆萌发富集γ-氨基丁酸的效果及工艺条件[J]. 食品工业科技，2023，44（22）：160−168. doi: 10.13386/j.issn1002-0306.2022120205XU Qingpeng, JIANG Xiujie, ZHANG Jiayu, et al. Effect and Process Conditions of Cold Plasma Combined withL-Glutamic Acid and Salt Stress on Germination and Enrichment of γ-Aminobutyric Acid in Adzuki Bean[J]. Science and Technology of Food Industry, 2023,44(22): 160−168. (in Chinese with English abstract). doi: 10.13386/j.issn1002-0306.2022120205· 工艺技术 ·冷等离子体联合L-谷氨酸与盐胁迫对红小豆萌发富集γ-氨基丁酸的效果及工艺条件许庆鹏，姜秀杰，张家瑜，魏春红，周航庆，张东杰*（黑龙江八一农垦大学食品学院，黑龙江大庆 163319）摘 要：为探究等离子体联合盐胁迫对红小豆萌发后γ-氨基丁酸（γ-Aminobutyric acid ，GABA ）含量的富集作用及效果。
本实验以红小豆为原料，考察大气冷等离子电压、频率、时间处理种子对其发芽过程中GABA 含量的影响，同时采用L-谷氨酸（L-Glu ）联合盐胁迫的发芽方法，通过考察单因素（发芽时间、CaCl 2、L-Glu 和NaCl 浓度）对GABA 富集量的影响及响应面优化试验确定该法富集GABA 最佳工艺。
结果表明，大气冷等离子体技术处理种子对其萌发富集γ-氨基丁酸有促进作用，电压90 kV 、频率120 Hz 、时间20 min 条件下大气冷等离子体处理效果较好。
