Vortex shear effects in layered superconductors

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伊顿 PS-386 合成变速箱润滑油数据表

Eaton PS-386 Synthetic Transmission FluidPS-386 is a synthetic transmission fluid designed for fuel efficiency, extended drain intervals and severe service in heavy duty commercial vehicle transmissions which require a non-EP transmission lubricant. It is specially formulated to protect higher torque transmissions coupled with increased horsepower engines. It is approved for use in Eaton transmissions such as UltraShift PLUS, Fuller Advantage, FR and RT Series transmissions. Features:•Uniquely formulated toprovide up to 1.5 percent fueleconomy improvement whilemaintaining excellent shearstability.•Provides high performanceand extended draincapabilities in transmissions.•Excellent thermal andoxidation stability whichresists deposit and sludgeformation.•Advanced additive systemprovides excellent protectionfrom corrosion, foaming, rust,and wear.•High viscosity index syntheticbase fluid allows for superiorhigh and low temperatureperformance.•Provides friction retention,friction durability, andexcellent shear stability toensure and maintain smoothtransmission operationsthroughout the extendeddrain interval.•Formulated to reduce sumpoperating temperatures.S U P P O R TB AC K ED B YApplications:Recommended where wear, lowtemperatures or heat presentmajor problems and a non-EPlubricant is required. T ypicalusage includes transmissions,transfer cases, and wheel endhubs. Recommended commercialvehicle applications include linehaul, vocational, off-road, pick-upand delivery, and buses.APPROVALSEaton PS-386 SyntheticT ransmission Fluid is approved for these OEM specificatons:• Eaton PS-386 (supercedes PS-164 Rev 7)• Mack TO-A Plus• Navistar MPAPS B-6816 Type II• API MT-1Eaton ® PS-386 Synthetic Transmission FluidS U P P O R TB AC K ED B YNote: Features and specifications listed in this document are subject to change without notice and represent the maximum capa-bilities of the software and products with all options installed. Although every attempt has been made to ensure the accuracy of information contained within, Eaton makes no representation about the completeness, correctness or accuracy and assumes no responsibility for any errors or omissions. Features and functionality may vary depending on selected options.Eaton, Fuller, Roadranger, Solo, UltraShift and Fuller Advantage are registered trademarks of Eaton. All trademarks, logos and copyrights are those of their respective owners.For spec’ing or service assistance, call 1-800-826-HELP (4357) or visit /roadranger . In Mexico, call 001-800-826-4357.Roadranger: Eaton and trusted partnersproviding the best products and services in the industry, ensuring more time on the road.EatonVehicle Group13100 E. Michigan Ave.Kalamazoo, MI 49053 USA 800-826-HELP (4357)/roadranger © 2016 EatonAll Rights Reserved. Printed in USA.TCSL0022 0716T echnical DataT ypicalT est Characteristics P S -386methodViscosity, cSt ASTM D-445 100 °C 14.8 40 °C 95.1Viscosity, cP -40 °C 51,900 ASTM D-2983Viscosity index 163 ASTM D-2270Pour point, °C (°F) -42 (-44)ASTM D-97Fire point, °C (°F) 276 (528) ASTM D-92Flash point, °C (°F) 238 (460) ASTM D-92APIgravity,************°C 34.9 ASTM D-287Density, k g/l at 15.6 °C, 0.850 (7.09) ASTM D-1298(lbs/gal. at 60 °F)HandlingPlease refer to safety data sheet for details.Shelf lifeThe product in the original package can be stored for at least three years at ambient storage conditions without any deterioration.NoteThe data contained in this publication are based on our current knowledge and experience. In view of the many factors that may affect processing and application of our product, these data do not relieve processors from carrying out their own investigations and tests; neither do these data imply any guarantee of certainproperties, nor the suitability of the product for a specific purpose. Any descriptions, drawings, photographs, data, proportions, weights etc. given herein may change without prior information and do not constitute the agreed contractual quality of the product. It is the responsibility of the recipient of our products to ensure that any proprietary rights and existing laws and legislation are observed.。

一种基于粒子群算法的高聚物浆液参数识别方法[发明专利]

专利名称：一种基于粒子群算法的高聚物浆液参数识别方法专利类型：发明专利
发明人：李晓龙,姚文艺,贾赫扬,钟燕辉,张蓓,申震洲,李阳
申请号：CN202010855134.7
申请日：20200824
公开号：CN112017733A
公开日：
20201201
专利内容由知识产权出版社提供
摘要：本发明涉及化学注浆领域，涉及一种基于粒子群算法的高聚物浆液参数识别方法，包括：预处理；初始化每个粒子的速度、位置、适应值、个体历史最优适应值、个体历史最优位置、群体历史最优适应值、群体历史最优位置和当前迭代次数；粒子群算法迭代求解；判断是否执行了预定次数的运算或群体历史最优适应值是否达到了精度要求；识别得到化学反应动力学参数。

本发明通过利用粒子群算法从而可快速高效地识别高聚物浆液化学反应动力学参数，且得到的参数更为准确。

申请人：郑州大学
地址：450001 河南省郑州市高新技术开发区科学大道100号
国籍：CN
代理机构：长沙楚为知识产权代理事务所(普通合伙)
代理人：李大为
更多信息请下载全文后查看。

Vortex_Generators

Original idea from Donald E. SteinVortex generators have been utilizedon most of commercial aircraft. Ifobserved carefully, one can seevortex generators installed at specificlocations on Boeing aircraft: forinstance, on wing upper surface & onthe engine nacelles for the B737 &the B767. (see pictures, page 5)Some specific examples of vortexgenerator applications are shown inthe accompanying photographs.These devices have been installed in each case to enhance flying qualities, but each application has its own story. A brief discussion of what vortex generators do is necessary before the design decision process for specific applications can be discussed. As can be observed from the previous photographs, these devices are used in assorted sizes and combinations, and can be mounted in various locations on an airplane. What they all have in common, however, is that they all act like miniature wings, each creating lift perpendicular to its own surface. By creating lift, they each shed a downstream vortex which can influence airflow in two distinct ways:• The vortex interacts with the boundarylayer air on the aircraft surface behind thedevice by inducing high energy air fromoutside the boundary layer down to thesurface displacing low energy air in theprocess as shown in Figure 1.The air adjacent to the surface is re-energized, and by suitable tailoring of theconfiguration, the vortex generators can beused to delay, control, or sometimesprevent separation of the boundary layerfrom the surface. The wing vortexgenerators installed on the 737, 757 and767 are applications which take advantage of this mechanism.• The vortex is oriented by appropriate placement of the vortex generator in order to redirect airflowin the flow field so that adverse interactions are prevented or delayed. With this mechanism, the generators act as a flow deflector. The large vortex generators installed on the 767 and 737-300 nacelles are examples of applications which take advantage of this mechanism.Vortex generators have been used to increase aircraft speeds, improve initial buffet boundaries, improve control authority, and reduce vibrations induced by boundary layer separation on some aircraft. However, these reasons do not explain why vortex generators have been used on the Boeing 737, 757, and 767 aircraft. Vortex generators are used on these aircraft to improve high Mach pitch characteristics beyond initial buffet and to lower stall speeds in the landing configuration.Figure 1. A vortex generator reduces the boundary layer height & reduces boundary layer separationTo further indicate why vortex generators were used on these latest aircraft, the case history for the 767 is presented to explain why the airplane was configured with wing vortex generators and with the large vortex generator installed on each engine fan cowl.WING VORTEX GENERATORSDuring the early design phase of the 767, morestringent high angle of attack stabilityrequirements were established. Specifically, thenew requirements established criteria foracceptable stick force vs. g (load factor)characteristics for pitch maneuvers above theangle of attack for initial buffet.Reduced stick force gradients at angles of attackbeyond initial buffet are typical for low tail, sweptwing aircraft due to the tendency for theboundary layer air on the outboard wing panel toseparate prior to the inboard wing. Although theprobability of encountering these characteristicsin normal service is very small, history hasshown that high speed upsets followed by high load factor recoveries do occur. It was the Boeing Company's desire that this new requirement be met by aerodynamic means,although a solution by means of a pitch augmentation control system was carefully considered . This alternative was not desired since it would add cost and complexity to the airplane.Early 767 wind tunnel test results showed, as expected, that the configuration with the best aerodynamic cruise efficiency displayed predicted stick force per g characteristics similar to previous low tail, swept wing transports and did not meet the more stringent design criteria beyond initial buffet. For optimum efficiency, a wing is designed to achieve an approximate elliptic spanwise lift distributionat cruise angle ofattack as shown inFigure 2.This loading minimizeslift induced drag andthereby maximizes liftto drag ratio. Theelliptical lift distributionis accomplished byproper selection ofairfoil camber and twist along the wing span.The resulting sectional lift coefficient variation with span is presented in Figure 3. On a swept wing planform, the largest increase in section lift coefficient with increasing angle of attack occurs on the outboard region of the span as seen in Figure 4. This is because wing sweepback causes the outboard wing to operate in a local upwash field created by the inboard wing; therefore, the outboard wing effectively operates at a higher angle of attack than the inboard wing.Figure 2. A wing is designed to achieve an approximately elliptical spanwise lift distribution at cruise angle of attack Figure 3. Sectional lift coefficient variation relative to spanFigure 4. On swept wing airplanes, the greatest increase in section lift coefficient with increasing angle of attack occurs on the outboard region of the spanAnother important factor is the spanwise flow of the low energy boundary layer air which makes the outboard wing more susceptible to initial flow separation. The loss of outboard wing lift at high angles of attack is the direct cause of the reduction in stick force per g for swept wing airplanes.Several candidate design modifications were studied as configuration options for improving the stick force per g characteristics to meet the new design requirements:• Several T-tail configurations were studied in order to separate the wing flow field from the horizontal tail• The wing span loading was modified by retwisting the wing to unload the outboard wing• The inboard wing airfoils were modified in order to promote initial separation on the inboard wingEach of the above options resulted in a significantly less efficient airplane. A better solution was desired, and vortex generators provided that solution. A 1/10 scale model of the 767 airplane was built and tested at a high Reynolds number wind tunnel in order to obtain data simulating full scale 767 conditions. Vortex generators were evaluated in detail. The test results were very encouraging because it was determined that only a few small vortex generators located on the wing just outboard of the nacelle were very effective in improving the wing stall pattern and hence the stick force characteristics. It remained to be proven on the flight vehicle.The early flight tests on the 767 airplane without the vortex generators confirmed the initial wind tunnel test results. When vortex generators were added, the stick force characteristics beyond initial buffet met the new Boeing design requirements. The vortex generators also provided increased buffet intensity with increasing load factor thereby contributing additional deterrence to a pilot as he pulled into these conditions. The production vortex generator configuration required only seven 3/4 inch high vortex generators per wing shown in Figure 5. The effect on weight and drag were negligible.NACELLE CHINEThe large vortex generator installed on the inboard side of the nacelle is commonly called a nacelle chine as shown in the 767 photograph at the end of the article. These devices are used on both the 767 and 737 airplanes. Modem efficient aircraft utilize high bypass ratio engines mounted from pylons off the wing. In order to minimize landing gear length (minimize weight) and to maintain adequate runway clearance (minimize foreign object ingestion), the engines are installed in relative close proximity to the wing as shown in Figure 6.Figure 5. Model 767 wing vortex generators Figure 6. Relationship of landing gear length to nacelle lipheight on high-bypass ratio engines.This close coupling of the large engines with thewing results in increased flowfield interactionbetween the engines and the wing at high angles ofattack, and can result in reduced airplaneperformance unless special consideration is givento counteracting these effects. One such adverseinteraction is a loss in maximum wing lift capabilityin the landing configuration. At the high angles ofattack required at low airspeeds, vortices are shedfrom the fan cowl. For engine installations wherethe nacelle is located further below the wing, such as JT9D installations on the 747, these vortices pass underneath the wing. For more close couplednacelle configurations, these vortices flow over thetop of the wing and interact with the wing flowfield. The effect of these vortices is generally favorable as long as they remain intact. Unfortunately the wing, at high angle of attack, will impose large adverse pressure fields on these vortices as they flow rearward along the wing surface as shown in Figure 7.These vortices will break up and burst, causing the boundary layer airover the wing behind the engine to separate. This results in lowermaximum lift levels than would be the case with less closely couplednacelles as shown in Figure 8.The solution was the development of a large vortex generatorinstalled on the inboard side of the engine nacelle which wassufficient to delay the nacelle vortex bursting phenomenon. TheBoeing invention disclosure identifies this as a vortex control device(VCD), but it is more commonly known as a nacelle chine. The nacelle chine was sized andpositioned on the inboard side of the nacelle tocontrol where the nacelle vortex is shed so that it willnot attach to the wing. The strong vortex shed bythe nacelle chine will cause the nacelle vortex toflow over the wing as shown in Figure 9 delaying thewing influence to burst the vortices until a higherangle of attack. The result is that the lift loss shown in Figure 9 is essentially regained as shown in Figure 10. Due to air condensation under certain atmospheric conditions, the vortex shed by the nacelle chine can be clearly viewed from the cabin as shown in Figure 11. In terms of airplane performance, the nacelle chine reduced approach speeds by 5 knots and landing field lengths by approximately 250 feet for the 767-200 as shown in Figure 12. The nacelle chine is a significant contributor to thesuperior short field performance of the 767.Figure 7. Wing vorticies resulting from close coupling of largeengines to the wing Figure 8. Effect of nacelle chines on lift Figure 9. Effect of the nacelle chine on the nacelle vortex Figure 10. Regained lift loss due to theuse of chinesOPERATIONAL CONSIDERATIONSEach airplane in the fleet should be periodically inspected to determine if all the vortex generators are installed. On most models, dispatch is allowed with a limited number of missing vortex generators. The Configuration Deviation List (CDL) in the Airplane Flight Manual should be consulted to determine the minimum number required for dispatch and whether operational limitations are to be imposed. Repair and replacement of vortex generators is explained in the appropriate Maintenance Manual for each model.CONCLUSIONS Array Vortex generators are avaluable aerodynamic toolwhich can be used byaircraft designers toenhance airplane flyingqualities. Judicious use ofvortex generators resultsin optimum aerodynamiccharacteristics over a widerange of flight conditions(e.g. from cruise flight toFigure 12. Approach speed & landing field length effect of nacelle chineshigh g and/or high angle ofattack maneuvers into heavy buffet). The use of these devices on the new Boeing aircraft have contributed to:• more efficient aerodynamic designs with low fuel bum performance• aircraft with lower initial cost and maintenance expense。

基于Real-ESRGAN的岩石CT图像超分辨率重建

基于Real−ESRGAN 的岩石CT 图像超分辨率重建李刚，张亚兵，杨庆贺，邹军鹏，才天，刘航，赵艺鸣（辽宁工程技术大学矿业学院，辽宁阜新　123000）摘要：图像采集设备和地质环境等因素导致岩石CT 图像分辨率低、细节不清晰，而现有图像超分辨率重建方法在表征内部高密度矿物质颗粒和孔裂隙时容易丢失细节。

针对上述问题，采用改进的增强型超分辨率生成对抗网络（Real−ESRGAN ）对岩石CT 图像进行超分辨率重建。

选取山西晋城无烟煤矿业集团有限责任公司赵庄煤矿15号煤层底板的砂岩为研究对象，研究不同图像放大倍数下Real−ESRGAN 的重建性能，并将其与超分辨率卷积神经网络（SRCNN ）、超分辨率生成对抗网络（SRGAN ）、增强型超分辨率生成对抗网络（ESRGAN ）、增强的深度超分辨率网络（EDSR ）等算法进行对比。

试验结果表明：① 使用Real−ESRGAN 重建的高分辨率图像在视觉效果上比原始CT 图像更清晰，重建图像中裂隙轮廓和高密度矿物质颗粒更加突出，图像可视性得到了极大提高。

② 在客观评估方面，Real−ESRGAN 算法在2倍超分辨率重建后图像的峰值信噪比（PSNR ）高达36.880 dB ，结构相似性（SSIM ）达0.933。

但随着放大倍数的增加，6倍超分辨率重建图像上的孔隙出现模糊，PSNR 降至32.781 dB ，SSIM 为0.896。

③ Real−ESRGAN 重建超分辨图像的孔隙率和喉道长度分布占比与原始CT 图像相比非常接近，保留了岩石重要的细观结构信息。

关键词：岩石CT 图像；超分辨率重建；生成对抗网络；图像处理；岩石细观结构中图分类号：TD67 文献标志码：ASuper-resolution reconstruction of rock CT images based on Real-ESRGANLI Gang, ZHANG Yabing, YANG Qinghe, ZOU Junpeng, CAI Tian, LIU Hang, ZHAO Yiming(College of Mining, Liaoning Technical University, Fuxin 123000, China)Abstract : Due to factors such as image acquisition equipment and geological environment, rock CT images have low resolution and unclear details. However, existing image super-resolution reconstruction methods are prone to losing details when characterizing high-density mineral particles and pores and cracks inside. To solve the above problems, an improved enhanced super-resolution generative adversarial network (Real-ESRGAN) is used for super-resolution reconstruction of rock CT images. The sandstone of the 15th coal seam floor in Zhaozhuang Coal Mine, Shanxi Jincheng Anthracite Mining Group Co., Ltd. is selected as the research object to study the reconstruction performance of Real-ESRGAN under different image magnifications. It is compared with algorithms such as super-resolution convolutional neural network (SRCNN), super-resolution generative adversarial network (SRGAN), enhanced super-resolution generative adversarial network (ESRGAN), and enhanced deep super-resolution network (EDSR). The experimental results show the following points. ① The high-resolution images reconstructed using Real-ESRGAN have clearer visual effects than the original CT images. The contours of cracks and high-density mineral particles in the reconstructed images are more prominent,greatly improving the visibility of the images. ② In terms of objective evaluation, the Real-ESRGAN algorithm收稿日期：2023-08-26；修回日期：2023-11-16；责任编辑：盛男。

Vortex Charging Effect in a Chiral $p_xpm i p_y$-Wave Superconductor

1
I. INTRODUCTION
The discovery of many types of superconductors from heavy fermion compounds to high-Tc cuprates has driven us to study a large variety of new physics beyond the standard BCS theory for conventional s-wave superconductors. The study of the unconventional superconductivity was stimulated by the discovery of superﬂuid 3 He in which a spin triplet p-wave state realizes. Unlike the conventional s-wave state, the p-wave state has both spin and orbital degrees of freedom. This is the most pronounced feature of the unconventional superconductors observed in their thermodynamics and impurity eﬀects or detected by tunneling spectroscopy, NMR, µSR measurements, and so on. Sr2 RuO4 is the ﬁrst layered perovskite compound showing superconductivity without CuO2 planes.1 The recent experimental and theoretical studies have indicated that the superconducting pairing symmetry of Sr2 RuO4 is not a simple s-wave. The absence of a Hebel-Slichter peak in NQR2 and the sensitivity of Tc on non-magnetic impurities3 point towards unconventional pairing. The indication of broken time reversal symmetry,4 observed in µSR measurements, gives a strong argument for the unconventional paring state. The Knight shift experiment shows that the spin susceptibility is not aﬀected by the superconducting state,5 which is the strong evidence of a spin-triplet pairing. Sigrist et al. suggested that a px ± ipy -wave state, which breaks the time reversal symmetry in a tetragonal crystal ﬁeld, is the most likely pairing state for Sr2 RuO4 .6 The line node behavior is reported in the latest experiments7–9 −1 related to the low temperature thermodynamical measurements, such as speciﬁc heat and NMR T1 . An orbital 10 11,12 dependent superconductivity and gap anisotropy were suggested to understand the line node behavior. Here we focus on the px ± ipy -wave pairing state, since this representation is the simplest and essential form. We will see rich physics of this chiral state. The most intriguing character of the px ± ipy -wave state is that the Cooer pair has ±1 angular momentum, i.e. the pair electrons are rotating. This property is similar to that of the A phase of the superﬂuid 3 He. Due to the violation of the time reversal symmetry, we have two types of vortices, one of which is in the same direction to the angular momentum of the rotating Cooper pair, and the other is in the opposite direction. The rotating pair shows up in quasiparticle states around a vortex core. In this letter we present an interesting new physics related to a vortex. We focus on a vortex charging eﬀect.13 It was pointed out that for an s-wave superconductor the vortex charge is proportional to the slope of the density of states at the Fermi level.14 Hayashi et al. has proposed that the vortex charge is determined by the quasiparticle structure in the vortex core15 rather than the slope of the density of states. Very recently, it has been reported that Chern-Simons terms lead to a fractional vortex charge for the px ± ipy -wave state.16 Thus the origin of the vortex charge is still controversial. To make this point clearer, we investigate the vortex charging eﬀect in the chiral px ± ipy wave state, concentrating our attention on a microscopic origin of the vortex charge. This is demonstrated by solving the BdG equation self-consistently, including both charge and current screenings. This is the ﬁrst full self-consistent BdG study of a single vortex. We would like to show how the rotating Cooper pair shows up in the vortex charging eﬀect. This paper is organized as follows. In Sec. II, we present our formulation for calculating the quasiparticle states near the vortex core based on the BdG equation. In Sec. III, we show numerical results. We give summary and discussions in Sec. IV.

杰克逊 DMC-GX85KK 相机产品说明书

LUMIX GX85 4K Mirrorless Interchangeable Lens Camera Kit, 12-32mm Lens, 16 Megapixels, Dual Image Stabilization, Electronic Viewfinder, WiFi - Black DMC-GX85KK TYPE Type Digital Single Lens Mirrorless cameraRecording media SD Memory Card, SDHC Memory Card, SDXC Memory CardRecording media (Compatible with UHS-I UHS Speed Class 3 standard SDHC / SDXC Memory Cards)Image sensor size 17.3 x 13.0 mm (in 4:3 aspect ratio)Lens mount Micro Four Thirds mountIMAGE SENSOR Type Live MOS SensorTotal pixels 16.84 MegapixelsCamera effective pixels 16.00 MegapixelsColor filter Primary color filterDust reduction system Supersonic wave filterRECORDING SYSTEMAspect ratio 4:3, 3:2, 16:9, 1:1Image quality RAW, RAW+Fine, RAW+Standard, Fine, StandardImage quality MPO+Fine / MPO+Standard (with 3D lens in Micro Four Thirds system standard)Color Space sRGB, AdobeRGBContinuous recordable time (Motion picture) A VCHD [FHD/60i]: Approx. 100 min (rear monitor), 90 min(LVF) with H-FS12032Continuous recordable time (Motion picture) MP4 [4K/30p]: Approx. 80 min (rear monitor), 70 min (LVFH-FS12032Actual recordable time (Motion picture) A VCHD [FHD/60i]: Approx. 50 min (rear monitor), 45 min (LVFH-FS12032Actual recordable time (Motion picture) MP4 [4K/30p]: Approx. 40 min (rear monitor), 35 min (LVF) withFS12032Recording file formatStill image JPEG (DCF, Exif 2.3), RAW, MPO (When attaching 3D lens in Micro Four Thirds system standMotion picture A VCHD (Audio format: Dolby Digital 2ch), MP4 (Audio format: AAC 2ch)File size(Pixels)Still Image [4:3] 4592x3448(L) / 3232x2424(M) / 2272x1704(S) / 1824x1368 (When attaching 3D lens in MicFour Third system standard)Still Image [3:2] 4592x3064(L) / 3232x2160(M) / 2272x1520(S) / 1824x1216 (When attaching 3D lens in MicFour Third system standard)Still Image [16:9] 4592x2584(L) / 3840x2160(M) / 1920x1080(S) / 1824x1024 (When attaching 3D lens in MFour Third system standard)Still Image [1:1] 3424x3424(L) / 2416x2416(M) / 1712x1712(S) / 1712x1712 (When attaching 3D lens in MicFour Third system standard)Motion picture*MP4 N/AA VCHD N/AMP4* [4K] 3840x2160: 4K/30p 100Mbps, 4K/24p 100MbpsMP4* [Full HD] 1920x1080: FHD/60p 28Mbps, FHD/60p 28MbpsMP4* [HD] 1280x720: HD/30p 10MbpsMP4* [VGA] 640x480: VGA/30p 4MbpsA VCHD* [Full HD] 1920x1080 FHD/60p: 28Mbps, 60p recordingA VCHD* [Full HD] 1920x1080 FHD/60i: 17Mbps, 60i recordingA VCHD* [Full HD] 1920x1080 FHD/30p: 24Mbps, 60i recording (sensor output is 30fps)A VCHD* [Full HD] 1920x1080 FHD/24p: 24Mbps, 24p recordingWiFi FUNCTION WiFi IEEE 802.11b/g/n, 2412 MHz - 2462 MHz (1-11 ch), Wi-Fi / WPA / WPA2, Infrastructure modeNFC NoQR Code Connection YesPassword-less connection Yes (ON / OFF selectable)VIEWFINDER Type LCD Live View Finder (2,764,800 dots equivalent)Field of view Approx. 100%Magnification Approx. 1.39x / 0.7x (35mm camera equivalent) with 50 mm lens at infinity; -1.0 m-1Eye point Approx. 17.5 mm from eyepiece lensDiopter adjustment -4.0 - +3.0 (dpt)Eye sensor YesEye sensor adjustment High / LowFOCUS Type Contrast AF systemDFD technology YesPost Focus YesFocus Stacking N/AFocus mode AFS (Single) / AFF (Flexible) / AFC (Continuous) / MFAF mode Face/Eye Detection / Tracking / 49-Area / Custom Multi / 1-Area / PinpointAF mode (Full area touch is available)AF detective range EV -4 - 18 (ISO100 equivalent)Starlight AF YesAF assist lamp YesAF lock Yes (AF/AE LOCK button)Others One Shot AF, Shutter AF, Half Press Release, Quick AF, Continuous AF (during motion picturerecording), Eye Sensor AF, AF+MF, MF Assist, Touch MF Assist, Focus Peaking, Touch AF/AE Function,Touch Pad AF, Touch ShutterEXPOSURE CONTROLLight metering system 1728-zone multi-pattern sensing systemLight metering mode Multiple / Center Weighted / SpotMetering range EV 0 - 18 (F2.0 lens, ISO100 equivalent)Exposure mode Program AE, Aperture Priority AE, Shutter Priority AE, ManualISO sensitivity (Standard Output Sensitivity) Auto / Intelligent ISO / 100 (Extended) / 200 / 400 / 800 / 1603200 / 6400 / 12800 / 25600 (Changeable to 1/3 EV step)ISO sensitivity (Standard Output Sensitivity) (Up to ISO6400 in motion picture recording) (ISO Auto in Mmode)Exposure compensation 1/3 EV step ±5EV (±3EV for motion picture)AE lock Yes (AF/AE LOCK button)AE bracket N/AWHITE BALANCE White balance Auto / Daylight / Cloudy / Shade / incandescent / Flash / White Set 1, 2, 3, 4 / Color temperasettingWhite balance adjustment Blue/Amber bias, Magenta/Green biasColor temperature setting 2500-10000K in 100KWhite balance bracket N/ASHUTTER Type Focal-plane shutterShutter speed Still image: Still image: Time (Max. 2 minutes), 1/4,000 - 60Shutter speed Motion picture: 1/16,000 - 1/25Shutter speed Electronic shutter: 1/16,000 - 1Self timer 10sec, 3 images / 2sec / 10secRemote control N/ASCENE GUIDE Still image N/AMotion picture N/ABRACKET AE bracket 3, 5, 7 frames in 1/3, 2/3 or 1 EV Step, Max. ±3 EV, single/burstAperture Bracket 3, 5 or all positions in 1 EV stepFocus Bracket 1 to 999 frames, focus steps can be set in 5 levelsWhite balance bracket 3 exposures in blue/amber axis or in magenta/green axisPANORAMA SHOT Panorama shot Yes (Standard / Wide)BURST SHOOTINGBurst speed [Mechanical shutter] AFS: H: 8 frames/sec, M: 6 frames/sec (with Live View), L: 2 frames/secLive View)Burst speed [Mechanical shutter] AFC: H: 6 frames/sec, M: 6 frames/sec (with Live View), L: 2 frames/sec(with Live View)Burst speed [Electronic shutter] SH: 40 frames/secBurst speed [Electronic shutter] AFS: H: 10 frames/sec, M: 6 frames/sec (with Live View), L: 2 frames/secLive View)Burst speed [Electronic shutter] AFC: H: 6 frames/sec, M: 6 frames/sec (with Live View), L: 2 frames/sec (Live View)Number of recordable images More than 13 images (when there are RAW files with the particular speed)Number of recordable images More than 100 images (when there are no RAW files)Number of recordable images (depending on memory card type, aspect, picture size and compression)4K PHOTO MODE4K Photo mode* 4K Burst: 30 frames/sec4K Photo mode* 4K Burst (S/S): 30 frames/sec4K Photo mode* 4K Pre-Burst: 30 frames/sec, approx. 2 seconds4K Photo mode* (depending on memory card size and battery power)Exif information YesSelectable aspect ratio Yes (4:3 / 3:2 / 16:9 / 1:1 are selectable)Exposure mode Program AE/ Aperture-Priority / Sutter-Priority / Manual ExposureMarking function Yes (in 4K Burst (S/S) mode)Loop rec function Yes (in 4K Burst (S/S) mode)FLASH Flash type TTL Built-in-Flash, GN6.0 equivalent (ISO200 ・m) / GN4.2 equivalent (ISO100 ・m), Built-inup (Reference）Flash Mode Auto*, Auto/Red-eye Reduction*, Forced On, Forced On/Red-eye Reduction, Slow Sync., SlowSync./Red-eye Reduction, Forced Off * For iA, iA+ only.Synchronization speed Less than 1/160 secondFlash output adjustment 1/3EV step ±3EVFlash synchronization 1st. Curtain Sync, 2nd Curtain Sync.Synchronization for flash dimming and exposure compensation YesWireless control N/AREAR MONITOR Type TFT LCD monitor with static touch controlMonitor size Tilt 3.0-inch / 3:2 aspect / Wide viewing anglePixels Approx. 1,040k dotsFiled of view Approx. 100%Monitor adjustment Brightness, Contrast, Saturation, Red-Green, Blue-YellowLIVE VIEW Digital zoom 2x, 4xExtra Tele Conversion Still image: Max. 2xExtra Tele Conversion Motion picture: 2.4x (FHD), 3.6x (HD), 4.8x (VGA)Other functions Level Gauge, Real-time Histogram, Guide Lines (3 patterns), Highlight display (Still imagmotion picture), Zebra pattern (Still image / motion picture)DIRECTION DETECTION FUNCTIONDirection Detection Function YesSELF SHOT Self Shot Mode N/AShutter N/AEffect N/AFUNCTION BUTTONFn1, Fn2, Fn3, Fn4, Fn5, Fn6 N/AFn1, Fn2, Fn3, Fn4, Fn5, Fn6, Fn7, Fn8, Fn9 4K Photo Mode / Wi-Fi / Q.MENU / LVF/Monitor Switch / ALOCK / AF-ON / Preview / One Push AE / Touch AE / Level Gauge / Focus Area Set / Zoom Control / CurButton Lock / Dial Operation Switch / Photo Style / Filter Select / Aspect Ratio / Picture Size / Quality /Metering Mode / Bracket / Focus Mode / Highlight Shadow / i. Dynamic / i. Resolution / Post Focus / HDRShutter Type / Flash Mode / Flash Adjust. / Ex. Tele Conv. / Digital Zoom / Stabilizer / Snap Movie / MotioSet / Picture Mode / Silent Mode / Peaking / Histogram / Guide Line / Zebra Pattern / Monochrome Live VRec Area / Step Zoom / Zoom Speed / Touch Screen / Sensitivity / White Balance / AF Mode/MF / Drive MRestore to DefaultFn1, Fn2, Fn3, Fn4, Fn5, Fn6, Fn7, Fn8, Fn9, Fn10 N/APHOTO STYLE Still image and motion picture Standard / Vivid / Natural / Monochrome / L. Monochrome / Scenery / PortCustomCREATIVE CONTROLStill image Expressive / Retro / Old Days / High Key / Low Key / Sepia / Monochrome / Dynamic MonochrRough Monochrome / Silky Monochrome / Impressive Art / High Dynamic / Cross Process / Toy Effect / TPop / Bleach Bypass / Miniature Effect / Soft Focus / Fantasy / Star Filter / One Point Color / SunshineMotion picture Expressive / Retro / Old Days / High Key / Low Key / Sepia / Monochrome / DynamicMonochrome / Impressive Art / High Dynamic / Cross Process / Toy Effect / Toy Pop / Bleach Bypass /Miniature Effect / Fantasy / One Point ColorCREATIVE VIDEO MODEExposure mode Program AE / Aperture-Priority / Sutter-Priority / Manual ExposureMOTION PICTURE FUNCTIONCinelike gamma N/AFlicker reduction [1/50] / [1/60] / [1/100] / [1/120] / OFFPLAYBACK Playback function 30-thumbnail display, 12-thumbnail display, Calendar display, Zoomed playback (MaxSlideshow (All / Picture Only / Video Only / 4K PHOTO / Post Focus / 3D / Category Selection / Favorite,duration & effect is selectable), Playback Mode (Normal / Picture Only / Video Only / 4K PHOTO / Post F3D Play / Category / Favorite), Location Logging, RAW Processing, Light Composition, Clear Retouch, TiEdit, Text Stamp, Video Divide, Time Lapse Video, Stop Motion Video, Resize, Cropping, Rotate, RotationDisplay, Favorite, DPOF Print Set, Protect, Face Recognition Edit, Picture Sort, Creating Still Pictures froMotion PictureIMAGE PROTECTION / ERASEProtection Single / MultiErase Single / Multi / All / Except FavoritePRINT Direct Print PictBridge compatibleINTERFACE USB USB 2.0 High Speed MultiHDMI N/AHDMI** microHDMI TypeD / VIERA LinkHDMI** Video: Auto / 4K / 1080p / 1080i / 720p / 480pHDMI** Audio: StereoAudio video output NoRemote input N/AExternal microphone input N/AMicrophone Stereo, Wind-cut: OFF / Standard / HighSpeaker MonauralLANGUAGE OSD language Japanese, English, German, French, Italian, Spanish, Portuguese, Chinese (Traditional) GENERAL POWERBattery Li-ion Battery Pack (7.2V, 1025mAh, 7.4Wh) (Included)Battery AC Adaptor (Input: 110 - 240V AC) (Included, connect with USB cable)Battery life (CIPA standard) Approx. 290 images (rear monitor), 270 images (LVF) with H-FS12032Battery grip N/ADIMENSIONS / WEIGHTDimensions (W x H x D) 122 x 70.6 x 43.9 mm / 4.80 x 2.78 x 1.73 inch (excluding protrusions)Weight Approx. 426g / 0.94 lb (SD card, Battery, Body)Weight Approx. 383g / 0.84 lb (Body only)Weight Approx. 493g / 1.09 lb (SD card, Battery, H-FS12032 lens included)OPERATING ENVIRONMENTOperating temperature 0℃ to 40℃ (32°F to 104°F)Operating humidity 10%RH to 80％RHSTANDARD ACCESSORIESSoftware ・ The software to edit and playback images on computer is not bundled with DMC-GX85. To doPHOTOfunSTUDIO is available for download at Panasonic website using computer connected to the Interhttp://panasonic.jp/support/global/cs/soft/download/d_pfs99pe.html (For Windows)・ The software to process RAW file on computer is not bundled with DMC-GX85. To do this, SILKYPIXDeveloper Studio is available for download at Ichikawa Soft Laboratory's website using computer connectthe Internet.http://www.isl.co.jp/SILKYPIX/english/p/ (For Windows / Mac)Standard accessories DMC-GX85K KitStandard accessories Hot Shoe Cover, Battery Pack, AC Adaptor, USB Connection Cable, Shoulder StrapCapStandard accessories ・ The DMC-GX85 Operating Instructions for advanced features is available fordownloaded at Panasonic LUMIX Customer Support Site using PC, smartphone or tablet connected to theInternet.INTERCHANGEABLE LENS-1Lens Name LUMIX G V ARIO 12-32mm / F3.5-5.6 ASPH. / MEGA O.I.S.Lens Construction 8 elements in 7 groups (3 aspherical lenses, 1 ED lens)Nano Surface Coating -Mount Micro Four Thirds mountOptical Image Stabilizer Yes (MEGA O.I.S.)Focal Length f=12-32mm (35mm camera equivalent 24-64mm)Aperture Type 7 diaphragm blades / Circular aperture diaphragmAperture range N/AAperture N/AMaximum Aperture F3.5(Wide) - F5.6(Tele)Minimum Aperture F22Closest Focusing Distance 0.20m/0.66ft (at focal lenghts 12-20mm) / 0.30m/0.98ft (at focal lenghts 21-32mmMaximum magnification Approx. 0.13x / 0.26x (35mm camera equivalent)Diagonal Angle of View 84°(Wide) to 37°(TELE)Weatherproof N/AGeneralFilter Size 37mm / 1.5inMax. Diameter φ55.5mm / 2.2inOverall Length Approx. 24mm / 0.94in (from the tip of the lens to the base side of the lens mount)Weight [g] Approx. 70g (excluding lens cap, lens rear cap )Weight [oz] Approx. 2.47oz (excluding lens cap, lens rear cap )Others N/AINTERCHANGEABLE LENS-2Lens Name N/ALens Construction N/ANano Surface Coating N/AMount N/AOptical Image Stabilizer N/AFocal Length N/AAperture Type N/AAperture range N/AAperture N/AMaximum Aperture N/AMinimum Aperture N/AClosest Focusing Distance N/AMaximum magnification N/ADiagonal Angle of View N/AWeatherproof N/AGeneralFilter Size N/AMax. Diameter N/AOverall Length N/AWeight [g] N/AWeight [oz] N/AOthers N/ANOTES Image Stabilization System Image Sensor Shift Type (5-axis)TIME LAPSE SHOT YesSTOP MOTION ANIMATION YesSILENT MODE YesNOTE * About motion picture recording / 4K Photo recording- Use a card with SD Speed Class with "Class 4" or higher when recording motion pictures.- Use a card with SD Speed Class with "UHS-I UHS Speed Class 3 (U3)" when recording motion pictures w[MP4] in [4K] or [4K PHOTO].(SD speed class is the speed standard regarding continuous writing.)- Recording stops when the continuous recording time exceeds 29 minutes and 59 seconds or the file size ex4GB with [MP4] in [FHD] [HD] [VGA].- MP4 motion pictures with [MP4] in [4K]:- When using an SDHC memory card: You can continue recording without interruption even if the file sizeexceeds 4 GB, but the motion picture file will be divided and recorded/played back separately.- When using an SDXC memory card: You can record a motion picture in a single file.- When the ambient temperature is high or continuous recording is performed, the camera may stop therecording to protect itself. Wait until the camera cools down.** For [4K] video output, use an HDMI cable that has the HDMI logo on it, and that is described as"4Kcompatible".UPC885170285316。

托福阅读第三篇tpo75R -3原文+译文+题目+答案+背景知识

托福阅读第三篇tpo75R-3原文+译文+题目+答案+背景知识原文 (1)译文 (4)题目 (7)答案 (13)背景知识 (14)原文Seismic Waves①Seismic waves-energy waves produced by earthquakes-permit scientists to determine the location,thickness,and properties of Earth's internal zones.They are generated when rock masses are suddenly disturbed,such as when they break or rupture.Vibrations spread out in all directions from the source of the disturbance, traveling at different speeds through parts of Earth's crust and interior that differ in chemical composition and physical properties.The principal categories of these waves are primary,secondary,and surface. All three types of waves are recorded on an instrument called a seismograph.②Primary waves,or P-waves,are the speediest of the three kinds of waves and therefore the first to arrive at a seismograph station after there has been an earthquake.They travel through the upper crust of Earth at speeds of4to5kilometers per second,but near the base of the crust they speed along at6or7kilometers per second.In these primary waves,pulses of energy are transmitted as a succession of compressions and expansions that parallel the direction of propagation of the wave itself.Thus,a given segment of rock set in motion during an earthquake is driven into its neighbor and bounces back.The neighbor strikes the next particle and rebounds and subsequent particles continue the motion.Vibrational energy is an accordion-like push-pull movement that can be transmitted through solids,liquids and gases.Of course,the speed of Pwave transmission will differ in materials of different density and elastic properties.③Secondary waves,or S-waves,travel1to2kilometers per second slower than do P-waves.Unlike the movement of P-waves,rock vibration in secondary waves is at right angles to the direction of propagation of the energy.This type of wave is easily demonstrated by tying a length of rope to a hook and then shaking the free end.A series of undulations will develop in the rope and move toward the hook-thatis,in the direction of propagation.Any given particle along the rope, however,will move up and down in a direction perpendicular to the direction of propagation.It is because of their more complex motion that S-waves travel more slowly than Pwaves.They are the second group of oscillations to arrive at a seismograph station.Unlike Pwaves, secondary waves will not pass through liquids or gases.④Both P-and S-waves are sometimes also termed body waves because they are able to penetrate deep into the interior or body of our planet.Body waves travel faster in rocks of greater elasticity,and their speeds therefore increase steadily as they move downward into more elastic zones of Earth's interior and then decrease as they begin to make their ascent toward Earth's surface.The change in velocity that occurs as body waves invade rocks of different elasticity results in a bending or refraction of the wave.The many small refractions cause the body waves to assume a curved travel path through Earth.⑤Not only are body waves subjected to refraction,but they may also be partially reflected off the surface of a dense rock layer in much the same way as light is reflected off a polished surface.Many factorsinfluence the behavior of body waves.An increase in the temperature of rocks through which body waves are traveling will cause a decrease in velocity,whereas an increase in confining pressure will cause a corresponding increase in wave velocity.In a fluid where no rigidity exists,S-waves cannot propagate and P-waves are markedly slowed.⑥Surface waves are large-motion waves that travel through the outer crust of Earth.Their pattern of movement resembles that of waves caused when a pebble is tossed into the center of a pond.They develop whenever P-or S-waves disturb the surface of Earth as they emerge from the interior.Surface waves are the last to arrive at a seismograph station.They are usually the primary cause of the destruction that can result from earthquakes affecting densely populated areas.This destruction results because surface waves are channeled through the thin outer region of Earth,and their energy is less rapidly scattered into the large volumes of rock traversed by body waves.译文地震波①地震波是由地震产生的能量波，它们使科学家能够确定地球内部区域的位置、厚度和性质。

多翼离心风机气动噪声的降噪_张胜利

文章编号：1006-1355(2011)03-0166-05多翼离心风机气动噪声的降噪张胜利1,2，席德科1,2，李华星1,2，陆森林1,2，张仲寅1,2（1.西北工业大学航空学院，西安710072；2.陕西省风机泵工程研究中心，西安710072）摘要：针对多翼离心风机气动噪声的主要噪声源提出降噪方案。

首先，对于多翼离心风机涡流噪声的降噪，主要通过优化叶轮、蜗壳的结构几何参数和在叶轮出口加装旋转扩压器等方式进行。

其次，对于多翼离心风机旋转噪声的降噪，主要通过改变蜗舌形式进行。

最后对优化进出口安装角的叶轮和在叶轮出口加装旋转扩压器这两种降噪措施进行试验验证。

结果表明，改进后的风机与原型相比达到显著的降噪效果。

关键词：声学；多翼离心风机；气动噪声；降噪；实验研究；叶轮中国分类号：TH432文献标识码：ADOI 编码：10.3969/j.issn.1006-1355-2011.03.039Noise Reduction and Test Research of Aerodynamic Noise forMulti-blade Centrifugal FanZHANG Sheng-li 1,2,XI De-ke 1,2,LI Hua-xing 1,2,LU Sen-lin 1,2,ZHANG Zhong-yin 1,2(1.Aeronautics School Northwest Polytechnical Univercity ，Xi ’an 710072，China ;2.Shaanxi Province Fan &Pump Engineering Research Center ，Xi ’an 710072，China)Abstract :In this paper,some schemes of reducing the aerodynamic noise are proposed for multi-blade centrifugal fans.Firstly,the vortex noise can be reduced mainly through the optimization of the geometric parameters of the impeller and volute and installing a rotation diffuser in the outlet of the impeller.Secondly,the discrete noise can be reduced mainly by changing the form of volute tongue.Finally,the experimental verification is carried out for the two improved fans,one is designed with optimization of inlet and outlet blade angles,and the other is installed a rotation diffuser in the outlet.The tests show that the noise of the improved fans is reduced obviously in comparison with the prototype.Key words :acoustics ;multi-blade centrifugal fan ;aerodynamic noise;noise reduction ;test research ;impelle多翼离心风机（如图1）在工作时产生的噪声是环境噪声污染的主要来源之一，如厨房的吸油烟机的噪声可高达55～60dB [1]。

中图法与科图法简表对照一览-河海大学图书馆

写在前面春回大地，万象更新，在这春意盎然的时节里，新一期《图书馆最新资源速递》又如期与您见面了。

根据广大读者的需求，今年我馆在购置中文期刊时，新增订了近200种，为了方便您查找，我们已编制了《河海大学图书馆2008年度馆藏中文期刊目录》，并分发给各单位。

同时，我们将这近200种新增订的中文期刊目录单独列出，编辑在本辑《图书馆最新资源速递》的最后，以节省您查找新刊的时间。

本期继续报道外文会议录信息，希望我们的外文会议录专集对您查找会议文献有所帮助。

《图书馆最新资源速递》编辑体例如下：1、整体按分类编排：由于我馆的中文期刊是按《中图法》分类，中外文图书及外文期刊是按《科图法》分类，而这两种分类法又不尽相同，故我们将这两种分类的大类进行比较，相对集中并于目录中体现，目的是使推介的每一学科的内容尽量集中，以便读者更方便的使用；2、每一大类的内容按最新中文期刊目录、最新外文期刊目录、中文图书提要、外文图书提要的顺序编排；3、每一种推介的文献都注明了我馆的馆藏地。

4、我们的联系方式是：读者服务部（西康校区）：电话：83787308、83787307、83787302E-mail：zhongqz@ tsgxp@ tsgcbb@读者服务部（江宁校区）：电话：83787648E-mail：tsgcm@本期责任编辑：中文期刊——梁军；中文图书——许平；外文期刊——余清芬；外文图书——杨小莉。

本期供稿人员：周冰杨小莉宋艺丁马大勇郑林吴丽娣刘忠锦邓鸣超杨露曦熊易胡玲玲吴立志王唏红封丽陆艳洪建河海大学图书馆读者服务部2008. 4.3目录20 社会科学（C 社会科学总论） (5)中文期刊 (5)27 经济、经济学（F 经济） (9)中文期刊 (9)中文图书 (16)31/34 政治、社会生活/法律、法学（D 政治、法律） (17)中文期刊 (17)中文图书 (22)37 文化、科学、教育、体育（G 文化、科学、教育、体育） (27)中文期刊 (27)41 语言、文字学（H语言、文字） (29)中文期刊 (29)50 自然科学（N 自然科学总论） (31)中文期刊 (31)51-54 数学/力学/物理学/化学（O 数理科学和化学） (33)中文期刊 (33)中文图书 (36)外文期刊 (36)55-56 天文学/地球科学（P 天文学、地球科学） (58)中文期刊 (58)外文期刊 (60)58 生物科学(Q 生物科学) (87)中文图书 (87)65 农业科学（S 农业科学） (88)中文期刊 (88)中文图书 (89)外文期刊 (90)71-86 技术科学（T/X 工业技术/环境科学、安全科学） (91)中文期刊 (91)中文图书 (104)外文期刊 (136)外文会议录 (195)河海大学图书馆2008年新增中文现刊馆藏目录 (253)20 社会科学（C 社会科学总论）中文期刊社会科学[月刊]=Jornal of Social Sciences/上海社会科学院.—10期，2007年.—上海：上海社会科学院《社会科学》编辑部，（200020）.15.00元ISSN 0257-5833 CN 31-1112索书号：C/5 馆藏地：西康校区四楼本期目录内容新苏南模式与两新·组织党建运行机制——以江苏昆山市为实例…………………王世谊 (4) 政府在公民维权中的指导责任和接受监督……………………………………………汤啸天(16) 地方政府考核：双重委托人失效及其政策含义………………………………徐风华王俊杰(25) 泛长江三角洲：世界第六大都市圈未来“一体两翼·新格局…………………………张颊瀚(34) 税费改革后农村公共服务提供机制的比较研究——基于湖北与浙江农村的调查………………………………………………………………………………伏玉林符钢战(40) 论上海发展面临的虚拟经济膨胀问题…………………………………………………高炜宇(47) 社会情境理论：贫困现象的另一种解释…………………………………………………周怡(56) 浦东新郊区建设和人口城市化再推进研究……………………………………………孙嘉丰(63) 后形而上时代的“沟通主义法律观”——啜法律的沟通之维》代译序………………邓正来(69) 单位人格刑事责任沦纲……………………………………………………………………杜文(72) 沦行政行为的代表性…………………………………………………………樊明亚赖声利 (80) 对我国学前教育改革若干问题的文化观照……………………………………………华爱华(87) 《沦语》：孔子弟子博弈之成果——兼谈战国后期儒家八派之争及荀卿的态度……李露平(96) 中西和谐社会思想之异同：经济学说史的视角………………………………………钟祥财(105) 清末新政对民生问题的恶性操作与社会矛盾的激化…………………………………陆兴龙(115) 《月令》；农耕民族的人生模型……………………………………………………………薛富(123) 书生立武勋——湘军功成的内在因素…………………………………………………李志茗(134) 塞上海柴拉报势考略……………………………………………………………………褚晓琦(147) 墓惠与商道：近代上海慈善组织兴起的原因探析……………………………………汪华(154) 走向·间性哲学·的跨文化研究…………………………………………………………周宁(162) 空间，性别与认同——女性写作的·地理学·转向…………………………………陈惠芬（170）月西方理论和方法解析中国古代诗词——叶嘉莹中西诗学研究之阐释……………徐志啸（183）法商研究[双月刊]=Studies in LAW And Business/中南财经政法大学.—第1期，2008年.—武汉市：《法商研究》编辑部，（430073）.18.00元ISSN 1672-0393 CN 42-1664/D索书号：C5/73 馆藏地：本部四楼本期目录内容“美国对华铜版纸案”述评——基于反补贴申诉的考察……………………李仲平李炼(3) 美国反补贴法适用探析——以对“非市场经济国家”的适用为考察对象…………徐泉(10) WTO法律体系下实施“双反”措施的合法性研究——由“美国对华铜版纸案”引发的思考………………………………………………………………………………………臧立(16)从立法中心主义转向司法中心主义?——关于几种“中心主义”研究范式的反思、延伸与比较……………………………………………………………………………………喻中(22) 转化型抢劫罪主体条件的实质解释——以相对刑事责任年龄人的刑事责任为视角………………………………………………………………………………………刘艳红(29) 论我国股权激励的本土创新——股权分置改革视野下的反思与重构………………官欣荣(42) 论以人为本的“人”……………………………………………………………………胡锦光(48) 限时刑法探究……………………………………………………………………………黄明儒(55) 农民土地产权资本化经营实现的法律保障……………………………………………李丽峰(61) 城市土地节约利用法律制度：现状、问题与对策……………………………………王文革(69) 论现行保证制度的局限及其完善——以成本收益分析为中心………………………许德风(78) 保护传统文化的政策目标论纲…………………………………………………………黄玉烨(86) 我国新能源与可再生能源立法之新思维………………………………………………杨解君(92) 美国监管影响分析制度述评……………………………………………………………马英娟(98) 论犯罪的相对性——从绝对理性到相对理性…………………………………………张建军(107) 基于信息的荐证广告之法律规制——以保健品广告为中心…………………………吴元元(113) 环境罚款数额设定的立法研究…………………………………………………………程雨燕(121) 委托调解若干问题研究——对四个基层人民法院委托调解的初步考察……………李浩(133) 中国法律史研究思路新探………………………………………………………………邓建鹏(141) 中国法学会商法学研究会2007年年会综述…………………………………………冯兴俊(147) 第十五届全国经济法理论研讨会综述…………………………………………………管斌(153)复印报刊资料·社会学[月刊]Sociology.—第2期，2008年.—北京：中国人民大学书报资料中心，（100086）.10.00元ISSN 1001-344X CN 11-4250/C索书号：C91/3 馆藏地：本部四楼江宁二楼本期目录内容理论研究中国社会发展范式的转换：普遍性与特殊性……………………………………………刘新刚(3) 欧洲社会模式的反思与展望……………………………………………(英)安东尼·吉登斯(10) 分支学科自我行动与自主经营——理解中国人何以将自主经营当作其参与市场实践的首选方式……………汪和建(21) 声望危机下的学术群体——当代知识分子身份地位研究……………………………刘亚秋(37) 中国城市教育分层研究(1949-2003) …………………………………………………郝大海(51) 法律执行的社会学模式——对法律援助过程的法社会学分析………………王晓蓓郭星华(63) 社会发展系统打造农村现代职业体系的创新探索——武汉农村家园建设行动计划和实践的社会学分析之一……………………郑杭生(69) “活着的过去”和“未来的过去”——民俗制度变迁与新农村建设的社会学视野…………………………………杨敏(76) 社会问题解决社会问题的关键：协调好社会各群体之间的关系…………………………………李强(87) 环球视窗美国式的贫困与反贫困...........................................................................张锐(89) 索引 (92)英文目录 (96)领导科学[半月刊]=Leadership Science—第21期，2007年.—河南：领导科学杂志社编辑出版，（450002）.3.80元ISSN1003-2606 CN41-1024/C索书号： C93/8 馆藏地：本部四楼江宁二楼本期目录内容领导科学界的首要政治任务…………………………………………………………本刊编辑部（1）学习贯彻十七大精神把思想和行动统一到党的十七大精神上来——在2007年度省领导与社科葬专家学者座谈会上的讲话…………………………………………………………………………………徐光春（4）新一届中央领导集体治国理政的新方略(上) …………………………………………姜平（9）理论前沿关于领导、发展、以人为本的关系解读…………………………………………………王伟凯（ll）领导方法有效解决集体上访问题的思考与实践…………………………………………………陈丰林（14）引导信访户从“上访路”走上“致富路”………………………………………………邱金义（16）增强班子合力关键要合理分工…………………………………………………………枣甘（13）高校党建工作进网络的探索…………………………………………………张进超詹爱琴（17）市县领导欠发达地区构建和谐社会的着力点……………………………………………………丁善余（20）拓展农业发展思路的五种渠道…………………………………………………………盛高攀（22）乡镇领导推进乡镇党委和谐班子建设的途径……………………………………………………王晓宏（23）乡镇党委如何统揽工作全局……………………………………………………………刘久正（25）职工论坛建立体现科学发展观要求的干部政绩考核机制………………………………………盛克勤（30）组织部门信访工作机制探索……………………………………………………………钟群妹（26）用人之道有效规范干部选任初始提名工作……………………………………………李明辉韩振松（32）如何用好有过失的干部…………………………………………………………………蒋红波（34）办公室领导办公室工作如伺体现科学发展观要求…………………………………………………王合清（36）怎样在被动服务中求得主动……………………………………………………………方黎（38）学术动态中国领导科学研究会2007年年会将在上海市召开 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(44)名家在线科学大家平民本色——记中国测绘科学研究院名誉院长、中国工程院院士刘先林眉 (56)群星闪烁 (59)公务员管理提高公务员考试科学性 (61)加强县乡公务员队伍建设必须从优化人员结构入手 (63)“在线学习”引领干部培训“网络化” (66)事业单位聘用制推行中常见问题与对策分析 (68)如何做好当前外国专家管理与服务工作 (68)西部地区海外引才的一道亮丽风景线 (70)巧用职称评聘“杠杆”支撑人才活力 (72)人才资源配置流动人员人事档案管理难点与对策 (74)搞好毕业生人事档案管理 (77)县域人才开发如何与国际化接轨 (79)集团文化建设落地的关键点 (80)国有企业“二线”人员的开发 (81)简明定位“薪”事不再重重 (83)公备员在受处分期间受到新的处分，处分期如何计算 (85)未满服务期辞职应如何承担违约责任 (86)27 经济、经济学（F 经济）中文期刊世界经济[月刊]=The Journal of World Economy /中国经济学会中国社会科学院世界经济与政治研究所．—第2期，2008年2月．—北京：《世界经济》编辑部，（100732）．15.00元ISSN1002-9621 CN11—1138/F索书号：F1/45本期目录内容国际贸易与国际投资研发全球化与本土知识交流：对北京跨国公司研发机构的经验分析…………………………………………………………………梁正，薛澜，朱琴，朱雪炜(3) 区际壁垒与贸易的边界效应…………………………………………赵永亮，徐勇，苏桂富(17) 国际金融国际分工体系视角的货币国际化：美元和日元的典型事实……………………徐奇渊，李婧(30) 存在金融体制改革的“中国模式”吗…………………………………………………应展宇等(40) 宏观经济学习惯形成与最优税收结构…………………………………………………………邹薇，刘勇(55) R&D溢出渠道、异质性反应与生产率：基于178个国家面板数据的经验研究……………………………………………………………………………高凌云，王永中(65) 中国经济三种自主创新能力与技术进步：基于DEA方法的经验分析……………李平，随洪光(74) 经济史明代海外贸易管制中的寻租、暴力冲突与国家权力流失：一个产权经济学的视角……………………………………………………………………………………郭艳茹(84) 会议综述第一届青年经济学家研讨会(YES)综述 (95)经济与管理研究[月刊]=Research on Economics and Management/首都经济贸易大学．—第2期，2008年2月．—北京：《经济与管理研究》编辑部，（100026）．10.00元ISSN1000-7636 CN11—1384/F索书号：F2/8本期目录内容会议纪要努力探索中国特色国有公司治理模式——中国特色国有公司治理高层论坛综述 (5)专题论坛改革开放与国有经济战略性调整………………………………………………………王忠明(13) 股权多元化的国有控股公司治理结构特点及其构建………………………………魏秀丽(21) 剩余权的分配与国企产权改革……………………………兰纪平，罗鹏，霍立新，张凤环(28) 企业创新需求与我国自主创新能力的形成：基于收入分配视角………………………张杰，刘志彪(33) 集成创新过程中的三方博弈分析……………………………………………宋伟，彭小宝(38) 创新与企业战略制定模式的演进………………………………………刘鹏，金占明，李庆(43) 企业管理大型国际化零售企业经营绩效的影响因素分析………………………………蔡荣生，王勇(49) 跨团队冲突与组织激励机制分析………………………………………………李欣午(54) 运用基尼系数增强企业薪酬制度的公平性……………………………王令舜，马彤(59) 三农研究乡村旅游发展的公共属性、政府责任与财政支持研究……………单新萍，魏小安(64) 论失地农民长效保障机制的构建………………………………………………魏秀丽(69) 资本市场外资银行进入与东道国银行体系的稳定性：以新兴市场国家为例………………张蓉(74) 挤兑风险与道德风险的权衡：显性存款保险制度下最优保险范围的制定…冯伟，曹元涛(80) 贸易经济在反倾销中对出口商利益的考量………………………………………………金晓晨(86) 我国加征出口关税政策思辨…………………………………………夏骋祥，李克娟(90) 名刊要览公司治理和并购收益 (94)规制——自由化的必由之路：以色列电信市场1984-2005 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馆藏地：西康校区四楼本期目录内容贯彻落实科学发展观开创中央企业又好又快发展新局面.................................李荣融（4）努力做好新形势下的监事会工作..................................................................黄丹华（8）资产评估行业发展的重要里程碑...............................................................朱志刚（13）加快评估立法步伐加强评估法律体系建设................................................石秀诗（15）资产评估行业将进入新的发展时期............................................................李伟（16）提升资产评估执业质量促进资本市场健康发展..........................................李小雪（17）评估准则对中国不动产及相关资产评估的作用..............................埃尔文.费南德斯（18）发挥评估准则对中国资产评估行业健康发展的作用.......................................林兰源（20）正确发展适合中国国情的评估准则..........................................格来格.麦克纳马拉（21）财政部国资委关于印发《中央企业国有资本收益收取管理暂行办法》的通知 (22)财政部关于印发《中央国有资本经营预算编报试行办法》的通知 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(55)国有公司治理结构存在的问题及其法律风险防范……………………………………王玉宝（61）加强对外投资及多种经营监管…………………………………………………………张凯（64）盈余管理对企业有益性的探讨…………………………………………………………葛晓红（66）国有企业引进战略投资者的策略……………………………………………屈艳芳郭敏（68）促进我国企业内部控制的建设………………………………………………张宜霞文远怀（71）企业年金信托管理的治理结构研究(一) ……………………………………李连仁周伯岩（74）美英国家政府绩效考评对我国的启示与借鉴…………………………………………聂常虹（76）复印报刊资料·外贸经济、国际贸易[月刊]=Economy of Foreign Trade And Internaional Trade.—第1期，2008年.—北京：中国人民大学书报资料中心，（100086）.11.00元ISSN 1001-3407 CN 11-4289/F索书号：F7/17 馆藏地：西康校区四楼本期目录内容本刊综述2007年国际贸易与我国对外贸易问题综述………………………………………………王亚星(3) 研究与探讨试论新贸易理论之新……………………………………………………………郭界秀朱廷捃(9) 比较优势理论的有效性：基于中国历史数据的检验……………………………………管汉晖(14) 制度分析视角中的贸易开放与经济增长——以投资效率为中心……………………盘为龙(23) 国际贸易、外国直接投资、经济增长对环境质量的影响——基于环境库兹涅茨曲线研究的回顾与展望…………………………胡亮潘厉(30) 贸易政策贸易模式与国家贸易政策差异…………………………………………………………曹吉云(37) 分工演进对贸易政策的影响分析——基于交易成本的考虑…………………张亚斌李峰(44) 中国贸易结构的变化特点、决定要素以及政策建议……………………………………章艳红(50) 专题：进出口贸易二元经济结构、实际汇率错位及其对进出口贸易影响的实证分析……………………吕剑(56) 人民币汇率波动性对中国进出口影响的分析……………………………………谷宇高铁梅(66) 中国对外贸易出口结构存在的问题……………………………………………………魏浩(75) 服务贸易国际知识型服务贸易发展的现状、前景及我国对策分析……………………潘菁刘辉煌(80) 国际服务外包趋势与我国服务外包的发展……………………………………李岳云席庆高(86) 文摘加快我国资本输出和经济国际化的建议......................................................裴长洪(90) 双赢的中美经贸关系缘何被扭曲...............................................................李若谷(91) 索引 (93)英文目录 (96)复印报刊资料·市场营销 [月刊]=Marketing.—第2期，2008年.—北京：中国人民大学书报资料中心，（100086）.6.00元ISSN 1009-1351 CN 11-4288/F索书号：F7/26 馆藏地：西康校区四楼视点营销资讯 (4)特别关注激情燃烧的岁月——行将远去的2007…………………………………………………刘超等(6) 营销创新数字营销上路……………………………………………………………………………岳占仁(12) 手机广告：精准营销的黄金地段…………………………………………………………王浩(15) 论坛营销分析中小企业网上营销安全问题分析...............................................................潘素琼(17) 如何克服电子邮件营销中的广种薄收.........................................................郝洁莹(19) 国产洗发水何以走出迷局? (21)营销人物校长茅理翔………………………………………………………………………………叶丽雅(23) 营销策略博客营销策略……………………………………………………………………………缪启军(26) 企业社会责任标准下的出口营销策略转变……………………………………于晓玲胡日新(29) 品牌管理品牌管理的价值法则……………………………………………………………………辰平(30) 品牌延伸：中国企业需要补课……………………………………………………………曾朝晖(33) 渠道管理渠道模式：一半是火焰一半是海水………………………………………………………钱言(36) 弱势品牌渠道拓展之路…………………………………………………………吴勇毅陈绍华(39) 销售管理销售经理管控销售队伍的四种工具……………………………………………………谢宗云(41) 遭遇难题，见招拆招……………………………………………………………虞坚老树(44) 销售冠军是怎样炼成的——专访苏宁朝阳路店店长刘玉君…………………………齐鹏(47) 成功策划“右手之戒”成就戴比尔斯 (49)拉芳舍一个休闲餐饮王国扩张之谜……………………………………………………王翼(51) 阿尔迪最赚钱的“穷人店”………………………………………………………………杨育谋(53) 个案解读LG巧克力手机得失之间…………………………………………………………………林景新(56) 南京菲亚特：四面楚歌……………………………………………………………………陈宇祥(58) 奥克斯：反思“三大败笔”…………………………………………………………………刘步尘(62)财经科学[月刊]=Finance And Economics—第4期，2007年.—成都：《财经科学》编辑部，（610074）.8.00元ISSN1000-8306 CN51-1104/F索书号： F8/19 馆藏地：本部四楼江宁二楼。

中考英语太空探索成就单选题40题

中考英语太空探索成就单选题40题1. The first artificial satellite was launched by the Soviet Union in 1957. What was the name of this satellite?A. Sputnik 1B. Explorer 1C. Apollo 1D. Shenzhou 1答案：A。

解析：1957年苏联发射的第一颗人造卫星叫斯普特尼克1号。

选项B“Explorer 1”是美国发射的第一颗人造卫星；选项C“Apollo 1”是美国阿波罗计划中的一艘飞船，但不是第一颗人造卫星；选项D“Shenzhou 1”是中国发射的神舟一号飞船，与苏联发射的第一颗人造卫星无关，所以正确答案是A。

2. In which year did the United States send the first man to the moon?A. 1961B. 1969C. 1971D. 1979答案：B。

解析：1969年美国实现了首次载人登月。

1961年是苏联宇航员加加林首次进入太空的年份；1971年不是首次载人登月的时间；1979年与首次载人登月事件无关，所以正确答案是B。

3. Who was the first man in space?A. Neil ArmstrongB. Yuri GagarinC. Buzz AldrinD. Alan Shepard答案：B。

解析：尤里·加加林是第一个进入太空的人。

尼尔·阿姆斯特朗是第一个登上月球的人；巴兹·奥尔德林是第二个登上月球的人；艾伦·谢泼德是美国第一位进入太空的宇航员，但不是世界上第一个进入太空的人，所以正确答案是B。

4. The Apollo program was carried out by the United States. How many manned lunar landings were there in this program?A. 5B. 6C. 7D. 8答案：B。

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a r X i v :c o n d -m a t /0209286v 1 [c o n d -m a t .s u p r -c o n ] 12 S e p 2002Vortex shear eﬀects in layered superconductorsV.Braude and A.SternDepartment of Condensed Matter Physics,The Weizmann Institute of Science,Rehovot 76100,Israel(February 1,2008)Motivated by recent transport and magnetization measurements in BSSCO samples [B.Khaykovich et al.,Phys.Rev B 61,R9261(2000)],we present a simple macroscopic model describing eﬀects of inhomogeneous current distribution and shear in a layered superconductor.Pa-rameters of the model are deduced from a microscopic calculation.Our model accounts for the strong current non-linearities and the re-entrant temperature dependence observed in the experiment.I.INTRODUCTIONTransport measurements are widely used in studies of vortex dynamics of high-T c superconductors.When the current distribution in the sample is not homogeneous,the results of the measurements are usually interpreted in terms of a local resistivity tensor.Due to high anisotropy of these materials the in-plane resistivity ρxy is much smaller than the out-of-plane resistivity ρz .Commonly the resistivity is assumed to be a local function of the current density,and to depend on the applied magnetic ﬁeld and the temperature 2–4.A recent experiment by Khaykovich et al.1does not ﬁt into this scheme.In this experiment transport and magnetization measurements10101010012342030405060708090R [Ω]I c [A]T [K]10-710-510-310-10123R [Ω]I c [A]T [K]FIG.1.Resistance at various I a (left axis,log scale)and magnetically measured critical current (right axis,linear scale,open circles)vs T for the irradiated sample,H a =200Oe (a)and H a =500Oe (b)(taken from Khaykovich et al.1)in BSCCO crystals at elevated transport currents and perpendicular magnetic ﬁeld are performed,using high quality BSCCO platelets with current leads attached to the top surface and an array of 2DEG Hall sensors to the bottom surface.At a ﬁrst glance,the pictures that emerge from the transport and the magnetization mea-surements are mutually contradicting.Transport mea-surements reveal ﬁnite resistivity below the magnetic ir-reversibility line,in the superconducting state.This re-sistivity is non-monotonic with temperature,showing re-entrant behavior,and non-linear with current.As seen in the graphs of R vs.T ,Fig.1,at low transport currents R (T )is monotonic,dropping below experimental resolu-tion when temperature is reduced.At elevated currents,the resistance initially drops as T is lowered,but then goes up,the bump being steeper at lower currents.Also R (T )shows strong non-linearity,so that an increase of the current by 30%or less may result in enhancement of R by orders of magnitude.The source of this resistance is,presumably,vortex ﬂow as a response to the electric current.In contrast,local magnetization measurements in the presence of transport current,shown in Fig.2a,indicate that the vortices are pinned.These measurements can be well described in terms of the Bean model of the critical state 6,7.The model states that below the irreversibil-ity line the local current density equals either zero,or the critical current density,directed in such a way as to obtain the total transport current and the magnetiza-tion.The spatial distribution of the magnetic ﬁeld is then given by the Biot-Savart law 8.Since the current density nowhere exceeds the critical one,the Bean model predicts zero resistance.Within the Bean model ﬁnite resistivity can be expected only above the magnetically measured irreversibility line,which in Fig.2a occurs above 1600Oe.Indeed,at low I a the measurements (carried below the irreversibility line)show practically zero resistance.However,at elevated currents,substantial resistance is measured concurrently with the hysteretic magnetization well below the irreversibility line,as seen in Fig.2a.Fig-ure 2b shows the corresponding ﬁeld proﬁle B z (x ),ob-tained by the array of Hall sensors at 400Oe in presence of transport current on increasing and decreasing H a .A clear Bean proﬁle is observed.Fitting this proﬁle to the-200-150-100-50050100024681012040080012001600B z - H a [G ]R [m Ω]H a [Oe]= 30 K I a = 25 mATa 350400450B z [G ]Sensors #FIG.2.(a)Resistance (right axis)and hysteretic magneti-zation loop in the sample center (left axis)vs.H a at T =30K and I a =25mA.(b)Proﬁle of magnetic induction across the sample at 400Oe on increasing (•)and decreasing (◦)ﬁelds (taken from Khaykovich et al.1).theoretical ﬁeld distribution in platelet sample results in total critical current of I c =4.2A,which is more than two orders of magnitude higher than the transport cur-rent of 25mA.Figure 1shows I c (T )determined from the Bean proﬁles together with the resistive data.The re-entrant resistance always occurs in the region where zero resistance is expected,since the transport current is much lower than the critical current.Thus,the main puzzling observations of Khaykovich et al.are the nonvanishing resistance below the irreversibil-ity line,which indicates ﬂux ﬂow,coexisting with mag-netization measurements which indicate that the vortices are pinned,the re-entrant behavior of the resistance with the temperature and its strongly nonlinear dependence on the current.Khaykovich et al.1suggest the following qualitative un-derstanding of the observation.BSCCO,being a strongly anisotropic type II high T c superconducting material,consists of superconducting CuO 2layers,separated by in-sulating barriers.Each layer can carry current,resulting in total parallel current along the sample.Also,due to Josephson coupling between the layers,current can ﬂow perpendicular to the layers.Because of large anisotropy a typical ratio of the perpendicular and parallel resis-tivities is ≃104in the normal state.In perpendicular magnetic ﬁeld the ﬂux penetrates the system in form of vortices,but,due to weak interlayer coupling,these are two dimensional “pancakes”,rather than three di-mensional ﬁlaments.Pancakes in the same layer repelone another,while those in diﬀerent layers attract via Josephson and magnetic coupling 7.In the experiment,the leads are attached to the top surface of the crystal.Hence the current distribution is non-homogeneous along the sample thickness,planes near the bottom of the crys-tal carrying much lower current than those at the top.As temperature decreases,pinning of vortices becomes more eﬀective.Eventually the critical current density exceeds current density near the bottom.Then pancake vortices at the bottom stop moving,while pancakes at the top maintain their high velocity,since current den-sity there is much higher than the critical current den-sity.As a result,velocity gradient of pancake motion be-tween diﬀerent layers is increased.This,in turn,leads to shear-induced phase slippage between the adjacent CuO 2planes,reducing the Josephson coupling and increasing the perpendicular resistance ρz .The larger ρz causes the current to ﬂow in a thinner part of the sample,thus mak-ing the process self-enhancing.Since all of the transport current ﬂows in a few layers near the top of the sample,ﬁnite resistance exists at currents much lower than the critical current expected from the Bean model.Magne-tization measurements,on the other hand,measure the magnetic response of all layers.When the vortices are pinned in most layers,this response is irreversible.In this work we take this qualitative explanation as a starting point and construct macroscopic and micro-scopic models to analyze the experiment.We start by presenting a macroscopic model in which the sample is assumed to be constructed of a resistive part,an inter-face and a dissipationless part.The perpendicular resis-tivity of the resistive part is assumed to depend on ”vor-tex shear”.The parameters of this model are introduced phenomenologically.We then examine the dependence of the sample’s resistance on these parameters,and the con-clusions that may be drawn regarding the dependence of the resistance on the temperature and current.Following that we construct a microscopic model aimed at deriving an expression relating the conductivity in the direction perpendicular to the layers to the inter-layer variation of the current parallel to the layers.Finally we compare the conclusions of our model to the experimental ﬁndings.Although we ﬁnd a general agreement,we also point out some remaining diﬃculties,associated mostly with the lack of quantitative information regarding several of the parameters of the model.II.THE MACROSCOPIC MODELAs we focus here on the consequences of inhomogene-ity in the current distribution in z direction,we use a one-dimensional model in which all quantities can vary only in this direction.Since scales of interest are much larger than the microscopic scale deﬁned by the spac-ing between adjacent superconducting layers,we take a continuous limit in z direction.dissipationlessinterface 0d d zresistive FIG.3.The macroscopic model.The model is described as follows.A current J in is injected into a system of depth d from above.Part of the current then ﬂows horizontally as j x and the rest -vertically down as J z (then,of course,returning ver-tically up at the other end of the system).Below the depinning temperature T d ,when there is non-zero criti-cal current density j c ,the system can be divided into two parts,by the value of the in-plane current j x .The up-per part of the system carries current density larger than j c ,so it has ﬁnite resistance,while at the lower part the current density is smaller than j c ,and thus it has zero resistance.Accordingly,we consider the system as con-sisting of two phases:a resistive phase at the top,having parallel resistivity R x and perpendicular resistivity ρz /2,and a dissipationless phase with zero resistivity.Note,that since the current ﬁrst ﬂows down and then up,the total perpendicular resistivity it experiences is ρz .Fur-thermore,we assume that current crossing the interface between the two phases faces a resistance R int /2.The position of the interface is determined by the condition j x =j c .This condition also ﬁxes the current J out ﬂowing through the dissipationless region:J out R int =j c R x .(1)At high temperatures j c is zero,and the system consistsonly of the dissipative phase.The basic equations governing the distribution of the current in the dissipative phase are the two Kirchoﬀequa-tions.The continuity equation is (note that in the geom-etry we consider J z and j x have diﬀerent dimensions,since J z is a two dimensional current density,while j x is a three dimensional current density):∂z J z +j x =0(2)and the equation giving the total voltage is:V = zJ z (z ′)ρz (z ′)dz ′+j x (z )R x .(3)As we show below in the microscopic analysis,the z -axis resistivity depends on the diﬀerence between j x in adja-cent layers ∂z j x ,and this dependence may be approxi-mated by ρz =ρ0+ρ21+(f∂2z J z )2,(4)while R x is assumed to be a constant parameter.Theterm f∂z j x in the resistivity ρz is a contribution of the ”shear”between vortices in diﬀerent layers to the out-of-plane resistance.It originates from the eﬀect of a veloc-ity gradient between vortices in adjacent planes on the Josephson coupling between the planes.Substituting Eq.(2)into Eq.(3)and diﬀerentiating with respect to z we obtain:J z (ρ0+ρ0∂2z J z(6)is satisﬁed.Designating J ≡J z ,J ′′≡∂2z J z and solvingfor J ′′,we obtainJ ′′=1(R x ρ1/J )2+f 2(ρ20−ρ21) .(7)The condition (6)requires that plus sign be taken inEq.(7)and that J <J 0≡R x /f .This means that as J in →J 0,both J ′′and J ′diverge,so that the voltage V also diverges,and the system becomes insulating.In fact,as J in →J 0,current gradients in the system become large,and then the quasi-particle channel for z -axis cur-rents needs to be taken into account,as analyzed below.When doing this,we ﬁnd that J 0is actually not a cut-oﬀvalue for the injected current,but rather a parameter that signiﬁes the importance of shear eﬀects.Thus,when J in becomes comparable with J 0,shear becomes strong,and the resistance is strongly non-linear with J in .Substituting the solution for J ′′into Eq.(4),the per-pendicular resistivity can be expressed in terms of J :ρz =ρ01+1−κ2,(8)where we used reduced quantities κ≡J/J 0and r ≡ρ1/ρ0.It is plotted in Fig.4.Again,this is valid for J not too close to J 0.It is possible to integrate Eq.(7).Some intuition to it may be obtained by noticing that Eq.(7)may be viewed as an equation of motion for a particle whose one dimen-sional coordinate is J ,its ”time”is z ,and the potentialJ in =−R x J′(0)larger currents produce larger current gradients,which,in turn,increase the vertical resistivity ρz .The low temperature case,where there is an interface,is more complicated and depends on the value of the in-terface resistance R int .To investigate the dependence of the resistance on the current,we need to diﬀerentiate the expression R =−R x J ′(0)2(U (J out )−U (J in ))+j 2cdJ in=−R xdJ in+R xJ ′(0)J in J ′(0)dU (J in )J 2.(18)Substituting dU (J )/dJ =J ′′and multiplying by a posi-tive quantity −R x J ′(0),we obtaindRJ in−R 2(J in ).(19)The above derivative is deﬁnitely positive at J in ≈J 0,since,as we saw above,the Cooper pair channel gets blocked,and the resistance of the system rises abruptly as J in approaches J 0.Hence it is only left to determine the dependence on J in for J in <<J 0.For this case we can neglect the quasi-particle contribution and use the expression (7)for J ′′(0).After a minor manipulation we obtaindR1−dJ inJ in =J out∝R x ρ0(1−r 2)r 2+(j c f/R int )2(1−r 2)−R 2int .(21)The result is a decreasing function of R int .It is positive for small R int (which should be larger than fj c in order tosatisfy J out <J 0),negative for large R int and vanishes at R int =R int,0,given byR int,0=(R x ρ0+j 2c f 2/2)2−R 2x ρ20(1−r 2).(22)Thus,the dependence of theis controlled by the value of R int ,as For fj c <R int <R int,0the tonically with the current.But if R resistance decreases for small currents where J 1is the solution of an R x ρ0(1−r 2)r 2+(J 1/J 0)2(1−r 2)=The physical explanation for this the current is increased,the interface wards,increasing the thickness of the layer.If the interface is highly most of the current is shunted sipationless)part of the system,so upper layer thickness increases the tem.However,if the interface is R int ),most of the current ﬂows and by increasing its thickness the tem is decreased.Of course,at large rapid increase of ρz due to shear has the resistance increases anyway.Ascurrent appears only when J in≈above and below T d.The diﬀerence between the qualitative arguments of Ref.[the following qualitative way.J inﬂows into the system andJ(z)with an interface at z=d increased one may expect theincrease,thus increasingρz, pushing the interface upwards.crease inρz and the motion of then to increase the resistance.ferent picture:as J in is downward,thus reducing thethe interface and thethen in opposite directions.B.Dependence on theFor the case when there is noincreasing R x makes the mogeneous,so that j x(0)and janother way,J0≡R x/f grows. fects of inter-layer vortex shearvertical resistivityρz decreases. tance R is inﬂuenced by twoof R x directly increases R,this small currents.On the otherofρz it tends to decrease R, nant at strong currents,when Hence the resistance grows with it decreases with R x as J inC.Dependence on theNext we discuss thetance on the critical current.We pendence of various parameters on j c and consider only athe position of the interface and redistribution.To determine∂Rdj c=∂R∂J in J in=J out dJ out∂j c=−R x∂J in.(25)rents the dependence on j c becomes weaker.This is incontrast to the dependence on J in,which becomes verystrong as J in→J0.All this,of course,is valid when j cis strong enough that there is an interface in the system.III.PERPENDICULAR RESISTIVITY DUE TOPARALLEL CURRENT GRADIENTThe interplane transport properties of high-T c su-perconductors have been a subject of intense re-search over the past decade,both theoretical9,10andexperimental2,4,11–13.This transport,being of Joseph-son nature,is determined by the phase coherence be-tween the adjacent layers.For a superconductor in a perpendicular magneticﬁeld,the pancake vortex struc-ture determines the above properties through the phase distribution.The vortex structure in high-T c supercon-ductors exhibits a rich variety of phenomena,including decoupling,melting,pinning,Bose glass formation etc., due to thermalﬂuctuations14–17,point defects16–18or columnar defects17,19–22.For the perpendicular resistiv-ityρz,the microscopic origin of the dissipation is less obvious than for the in-plane resistivityρx,where it is understood in terms of the Lorentz force,acting on the pancakes.Koshelev10proposed a microscopic mechanism for interplane dissipation,in which the pancake dynam-ics are shown to inﬂuence the interplane conduction,and calculatedρz for the simplest case of non-interacting pan-cakes.Following Ref.10we analyze a simple microscopic model aimed at a derivation of a formula for a contri-bution to the resistivity inˆz direction(perpendicular to the layers)ρ3D z of a superconducting slab due to a gradi-ent in the current inˆx direction(parallel to the layers). Weﬁrst deriveρ3D z for a3-dimensional sample assum-ing no interactions between the vortex pancakes.Then we show how the results are modiﬁed in presence of in-terlayer and intralayer correlations between the pancake positions.Finally,we transform the3-D resistivity pa-rameters into a form appropriate for the1-dimensional model used in the previous section.That is,we show how R x,ρ0and f of the macroscopic model are derived from the resistivities of the3-dimensional model.A.Noninteracting pancakesWe assume a layered superconductor with noninter-acting pancake vortices in it.The vortices are mobile, and their relative diﬀusive motion provides a mechanism for perpendicular resistance.In addition,each layer car-ries a diﬀerent current,causing diﬀerent drift velocities of vortices in adjacent layers.This increases the decay of phase correlations in time,thus enhancing the perpen-dicular resistance.We start from the Kubo formula forﬁnite tempera-tures:σ3D z=sj2Jr2.(32)Now we assume that the pancakes in the layers are ran-domly placed,so that∇φv(−R1)∇φv(−R2) =0and∇φv(−R1,i)∇φv(−R1,j) =δi,j ∇φv(−R1,i)2 .(33)Then the square of a sum breaks into a sum of squares,so thatS(r,t)2 = i ([r−∆R1,i(t)]∇φv(−R1,i))2+ ([r−∆R2,i(t)]∇φv(−R2,i))2 .(34)Now we can write for each layer∆R(t)≈v t+δR(t),(35)where v is the drift velocity of vortices due to the cur-rent,andδR(t)is the diﬀusion term.It gives the maincontribution at zero current gradient,and we will copyit from the Koshelev’s ing the expression(32)we writeS(r,t)2 = i(r−v1t)2 R x;1,iR22,i2+ S diff(t)2 .(36)Now we calculate the averages:i R x2 12 d RR min,(37)where n is the density of the vortices and R min and R max-the lower and upper cutoﬀradii.Substituting this,weobtainS(r,t)2 =[(r−v1t)2+(r−v2t)2]πn ln R maxR min+ S2diff(t) ,(38) whereV=(v1+v2)/2and∆v=v1−v2.(39) Substituting this result back into Eq.(27)and using Koshelev’s result for S diff,we obtain:σ3D z(∆v)=sj2JR min−2πnDt ln(R2J/R2min)=sj2Jn ln(R J/a0)2πn ln(R J/a0)F 4Dππ2y−2j2J2Ds(Φ0/c)∂z j3Dx[n ln(R J/a0)]3/2exp(−πn ln(R J/a0)[4T/s2(Φ0/c)∂z j3Dx]2)πn ln(R J/a0)/s2(Φ0/c)∂z j3Dx].(44)Expanding this,we obtain for small current gradients:ρ3D z(∂z j3Dx )=T4n ln(R J/a0)D[s2c∂z j3Dx]2 ,(45)i.e.a parabolic dependence on∂z j3Dx.On the other hand,for large current gradients,ρ3D z(∂z j3Dx )=2D(ρ3D1)2+(f3D∂z j3Dx )2which gives a correct valueat zero current gradient and the asymptotic behavior at large current gradients.It also approximates quite wellthe behavior ofρ3D(∂z j3Dx )in the intermediate range ofcurrent paring the coeﬃcients,we obtain ρ3D0=16DTsj2J[n ln(R J/a0)]2f3D=2Dsc[n ln(R J/a0)]3/2.(47)B.Correlations between pancake positions Here we demonstrate how the results obtained above are modiﬁed in presence of inter-and intralayer correla-tions between pancake positions.Weﬁrst consider the eﬀect of interlayer correlations. The presence of such correlations can be crudely de-scribed by regarding pancakes in diﬀerent layers as tied together into vertical line segments of length L z,which move as a whole.These segments should be used instead of independent pancakes of previous subsection.The phase diﬀerencesδφ(r,t)and corresponding Josephson currents are created only at the ends of these segments (more exactly,between layers,where one segment ends and another one starts),while the middle parts of the segments do not contribute toδφ(r,t).This means,that the eﬀective concentration of vortices is reduced by a fac-tor L z/s.Next,since each line segment has an increased “mass”,the mobilityµand the diﬀusion constant D are now reduced by another factor L z/s.Finally,the ver-tical separation between the segments is L z instead of s for free pancakes.This means that the velocity diﬀerence between the segments due to current gradient is increased by L z/s.To take into account this and the reduction in the mobility in Eq.(43),theﬂux quantumΦ0should be multiplied by(L z/s)2.This speciﬁes,how the resistiv-ity parameters are modiﬁed in the presence of interlayer correlations.Next we turn to consider the intralayer correlations. Roughly speaking,these correlations cause pancakes in each layer to aggregate in clusters of size L xy,so that there are(L xy/a0)2pancakes in a cluster.Pancakes inside each cluster are ordered,while diﬀerent clusters move independently(actually,there is a hard-core repul-sion between them).Since vortices in the same cluster are not independent,Eq.(34)for the phase correlation square now reads asS(r,t)2 = α i∈α[r−∆R1,i(t)]∇φv(−R1,i) 2+ i∈α[r−∆R2,i(t)]∇φv(−R2,i) 2 ,(48)whereαis an index of a cluster,while i-of an indi-vidual pancake.For clusters which are far enough away, the diﬀerences in the location of individual pancakes in-side the cluster can be neglected.Then each such clus-ter gives a contribution to S(r,t)2 ,which is(L xy/a0)4 times larger than a contribution of an individual pancake. On the other hand,the concentration of the clusters is n(a0/L xy)2.To take both eﬀects into account,we should multiply n by(L xy/a0)2in theﬁnal result.Also,the diﬀusion constant(and the mobility)of each cluster is reduced by a factor(L xy/a0)2,while theﬂux quantum Φ0should be multiplied by the same factor.Substituting all these prescriptions into Eq.(47),we obtain the resis-tivity parameters in the presence of correlations between pancake positions:ρ3D0=16DT(L z/s)3[n ln(R J/a0)]2ρ3D1=(8π−16)DT(L z/s)3[n ln(R J/a0)]2 f3D=2Ds(L z/s)1/2Φ0j x(z)j redz(x,z)≡j3Dz(x,z)V(x,z)E redz(x,z)≡E3Dz(x,z)V(z) L x/20dx E red x(x,z)=j x(z)ρ3D x L x/20dx j red x(x,z)E z(z) L x/20dx E red z(x,z)=J z(z)ρ3D0 L x/20dx j red z(x,z)+J z(z)f3D L x/20dx j red z(x,z)∂z j x(z)j red x(x,z).(53) Then,in order to obtain the equations of the macroscopic model,we make two assumptions:ﬁrst,we neglect thederivative∂z j redx (x,z);second,we assume that the reduced quantities are not aﬀected by shear eﬀects,so we calculatethem from a linear model with f=0.The parameters of the macroscopic1D model are then given byR x=ρ3D x L x/20dx j red x(x,z) L x/20dx E red x(x,z)ρ0/2=ρ3D0 L x/20dx j red z(x,z) L x/20dx E red z(x,z)f/2=f3D L x/20dx j red z(x,z)j red x(x,z) L x/20dx E red z(x,z),(54)whereρ0and f are divided by2,since,as we explained in the beginning of the previous section,the perpendicular resistivity of the macroscopic model is taken to beρz/2. Toﬁnd the reduced quantities,we need toﬁnd the cur-rent distribution in a sample with constant resistivities ρ3D x andρ3D z.This amounts to solving the Laplace equa-tion with the boundary conditions j0x(x=0,z)=j0x(x= L x,z)=j0z(x,z=∞)=0,and j0z(x,z=0)=0,ex-cept two narrow regions near x=0and x=L x,where j0z(x,z=0)is,respectively,positive and negative.This describes contacts,attached to the top of the sample, where the currentﬂows into and out of the system.For simplicity we assumed here that the system is inﬁnitely thick inˆz direction.Choosing an appropriate form for j0z(x,z=0),we obtain:j0z(x,z)=sinh k0(w+αz)cos k0xsinh2k0(w+αz)+sin2k0x,(55)where w is the width of the contacts(w≪L x),α≡πL ycosh k0(w+αz)log coth k0(w+αz)/2ρ0/2=ρ3D0πsinh k0(w+αz)arctan1/sinh2k0(w+αz)f/2=f3D πsinh2k0(w+αz)arctan21/sinh k0(w+αz).(56)Here aﬁnite z should be taken,so that k0αz∝1.Then the hyperbolic functions give factors of order1,and the 1D parameters are given byR x=ρ3D x2L xL x L yf/2=f3Dπthe model.Hence we make only qualitative statements based on robust features of the model.First,the model predicts that the resistance grows with the current(at least for not too small currents),and thiscurrent non-linearity becomes very strong as J in→J0. This is consistent with the experimental ingthe results of the microscopic calculation Sec.III,we found that without correlations between the pancakes J0 is much larger than the relevant J in.However,in pres-ence of correlations its value is suppressed by a factor of (L xy/a0)(L z/s)5/2,thus making its value much closer to J in.If the ratios L xy/a0,L z/s are assumed to be10-15, J0becomes comparable with the experimentally relevant currents.This provides an explanation to the experimen-tal fact that the current non-linearity becomes strong be-low the depinning transition temperature T d,where cor-relations between the pancakes start to build up.Next, the model explains the feature of re-entrance,that is, the experimental observation that below the depinning transition the resistance increases as the temperature is decreased.According to the model,if the interface resis-tance R int is large enough,the resistance of the system grows with j c,which naturally starts to grow as the tem-perature is decreased below T d.Moreover,the model predicts that this rise in the resistance should be more pronounced for smaller currents,as indeed observed. Some ingredients are missing from our model.First, the model approximates R x to be independent of the intra-layer current.This approximation is presumably good above the depinning temperature,but becomes poor below that temperature,where intra-layer current induces vortex depinning.Second,a missing ingredient in our work is a microscopic derivation of the interface resistance R int,separating between the resistive and non-resistive parts of the sample.The microscopic origin we have in mind is that in the region between the two phases the pancake mobility is very sensitive to parallel current variation.Then a small current gradient is enough to cre-ate a large pancake velocity gradient,which would cause a large perpendicular resistance in that region.Our at-tempts to provide a microscopic derivation of R int and its temperature dependence led us to results that heavily depend on various microscopic parameters whose values and temperature dependences are not known.We were therefore led to leave R int as a phenomenological param-eter.Altogether,then,our work is able to explain the qual-itative features of the non-linear transport observed in Ref.1and unravel a unique feature of transport in super-conducting BSCCO samples in perpendicular magnetic ﬁeld.ACKNOWLEDGMENTSWe thank E.Zeldov and V.Geshkenbein for useful discussions.This work is supported by the Israel Science Foundation and the Victor Ehrlich chair.。

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