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Pulsatile electroosmotic flow of a Maxwell fluid in a parallel flat plate microchannel with asymmetric zeta potentials

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Applied Mathematics and Mechanics(english edition) 2018年第5期39卷 667-684页

作者： M.PeRALTA O.BAUTISTA f.MeNDeZ e.BAUTISTA Seccion de estudios de Posgrado e Investigacion eSIMe Azcapotzalco Instituto Politecnico NacionalCiudad de Mexico 02250Mexico facultad de Ingeniería Universidad Nacional Autonoma de MexicoCiudad de Mexico 04510Mexico

The pulsatile electroosmotic flow （Pe.f. of a Maxwell fluid in a parallel flat plate microchannel with asymmetric wall zeta potentials is theoretically analyzed. By combining the linear Maxwell viscoelastic model, the Cauchy equation, and the electric field solution obtained from the linearized PoissomBoltzmann equation, a hyperbolic par- tial differential equation is obtained to derive the.f.ow field. The Pe.f.is controlled by the angular Reynolds number, the ratio of the zeta potentials of the microchannel walls, the electrokinetic parameter, and the elasticity number. The main results obtained from this analysis show strong oscillations in the velocity profiles when the values of the elas- ticity number and the angular Reynolds number increase due to the competition among the elastic, viscous, inertial, and electric forces in the.f.ow.

关键词： pulsatile electroosmotic flow (Pe.f. flat plate microchannel asymmetric zeta potential Maxwell fluid

Biomimetics of Campaniform Sensilla:Measuring Strain from the Deformation of Holes

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Journal of Bionic engineering 2007年第2期4卷 63-76页

作者： Julian f. V. Vincent Sally e. Clift Carlo Menon Department of Mechanical engineering The University of BathBath BA2 7AYUK Advanced Concepts Team European Space Agency2201 AZ NoordwijkThe Netherlands

We present a bio-inspired strategy for designing embedded strain sensors in space structures. In insects, the campaniform sensillum is a hole extending through the cuticle arranged such that its shape changes in response to loads. The shape change is rotated through 90° by the suspension of a bell-shaped cap whose deflection is detected by a cell beneath the cuticle. It can be sensitive to displacements of the order of 1 nm. The essential morphology, a hole.f.rmed in a plate of fibrous composite mate- rial, was modelled by Skordos et al. who showed that global deformation of the plate （which can be.f.at, curved or a tube） induces higher local deformation of the hole due to its locally higher compliance. further developments reported here show that this approach can be applied to groups of holes relative to their orientation. , The morphology of the sensillum in insects suggests that greater sensitivity can be achieved by arranging several holes in a regular pattern; that if the hole is oval it can be ＂aimed＂ to sense specific strain directions; and that either by controlling the shape of the hole or its relationship with other holes it can have a tuned response to dynamic strains. We investigate space applications in which novel bio-inspired strain sensors could successfully be used.

关键词： campaniform sensillum strain displacement compliance hole remote sensing fibrous composite

Spring tube braces for seismic isolation of buildings

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earthquake engineering and engineering Vibration 2017年第1期16卷 219-231页

作者： V.Karayel e.Yuksel T.Gokce.f.Sahin Institute of Science and Technology Istanbul Technical University lstanbul 34469 Turkey faculty of Civil engineering Istanbul Technical University Maslak Istanbu1 34465 Turkey

Abstract： A new low-cost seismic isolation system based on spring tube bracings has been proposed and studied at the Structural and earthquake engineering Laboratory of Istanbul Technical University. Multiple compression-type springs are positioned in a special cylindrical tube to obtain a symmetrical response in tension and compression-type axial loading. An isolation floor, which consists of pin-ended steel columns and spring tube bracings, is constructed at the.f.undation level or any intermediate level of the building. An experimental campaign with three stages was completed to evaluate the capability of the system. first, the behavior of the spring tubes subjected to axial displacement reversals with varying frequencies was determined. In the second phase, the isolation floor was assessed in the quasi-static tests. finally, a scaled 3D steel frame was tested on the shake table using actual acceleration records. The transmitted acceleration to the.f.oor levels is greatly diminished because of the isolation story, which e.f.cts longer period and higher damping. There are no stability and se.f. centering problems in the isolation floor.

关键词： seismic isolation spring tube base isolation low-cost isolation

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对决

作者： (美)卡尔森(e.f. Carlson)

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从广东看中国的经济改革

科技导报 1991年第3期9卷 19-21页

作者： e.f.沃格尔美国哈佛大学

本刊副主编蔡德诚同志于1990年11月访美时,就中国经济改革问题采访了美国哈佛大学沃格尔(ezra ***)教授。本文根据访谈录音整理,并经沃格尔教授于今年2月参加上海经济发展国际研讨会时审阅认可,同意在本刊发表。

关键词：中国经济经济改革广东

Inter-relationship of Various Results in Analysis of （14.0 MeV／U） Pb＋Pb Reaction Using Mica and CN-85 Track Detectors

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Chinese Physics Letters 2005年第1期22卷 69-71页

作者： f.N.Khattak e.U.Khan TabassumNasir J.J.Baluch f.U.Khan U.W.C. GomalUniversityDeraIsmailKhanPakistan RadiationPhysicsDivision PINSTECHNiloreIslamabadPakistan DepartmentofPhysics GomalUniversityDeraIsmailKhanPakistan

Two detector materials mica and cellulose-nitrate(CN)-85 have been used to study (14.0MeV/u) Pb + Pb reaction. events of different multiplicities were registered in mica and CN-85 detectors using the 2π-geometry technique of solid state nuclear track detection. After removing the target material from the detectors the damaged trails in the detectors were revealed as tracks by proper chemical etching. The irradiated area of each sample was scanned and events of different multiplicities were traced. The binary events were bifurcated into elastic and inelastic events. The elastic binary events and three prong events, observed in the reaction, have been used to search out coe.f.cients Cμν in the presence of both the detectors, for the reaction under study. Using these coe.f.cients 3- and 4-prong events have been analysed. from the detailed analysis of the results of (14.0MeV/u) Pb+Pb reaction, obtained from mica and CN-85 track detectors we observed a great resemblance of results obtained from the two detectors. Combining the results of both the detectors, we report some important outcomes.

关键词： CN-85轨迹探测器高能物理学铅原子碰撞反应固态

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秋季应用乙烯利提高桃花芽对低温逆境的抗性

国外农学(果树) 1988年第4期 10-13页

作者： Durner e.f. 杨儒琳

于10月中旬用乙烯利和氨腈钙(Dormex)对8年生"Cresthaven"桃进行喷布。翌年1月测定了在-23℃田间条件下4小时后的花芽耐寒性差异。乙烯利处理花芽明显地比对照或Dormex处理花芽耐寒。花前至花期进行人工低温测定也显示出同样的差异。乙... 详细信息

于10月中旬用乙烯利和氨腈钙(Dormex)对8年生"Cresthaven"桃进行喷布。翌年1月测定了在-23℃田间条件下4小时后的花芽耐寒性差异。乙烯利处理花芽明显地比对照或Dormex处理花芽耐寒。花前至花期进行人工低温测定也显示出同样的差异。乙烯利处理的花芽盛花期约比对照晚7天。乙烯利处理树产量比其他处理和对照有所增加。

关键词：乙烯利桃花芽花芽发育 2-氯乙基膦酸植物生长调节物质低温逆境抗寒性

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Communications in Theoretical Physics 2020年第7期72卷 104-110页

作者： f Ungan M K Bahar S Pal M e Mora-Ramos faculty of Technology Department of Optical EngineeringSivas Cumhuriyet University58140SivasTurkey faculty of Science Department of PhysicsSivas Cumhuriyet University58140 SivasTurkey Department of Quality Assurance CQA(SA)DGQA Ichapur-Nawabganj24Pgs(North)743144West BengalIndia Centro de Investigación en Ciencias Instituto de Investigación en Ciencias Básicas y AplicadasUniversidad Autónoma del Estado de MorelosAv.Universidad 1001CP62209CuernavacaMorelosMexico facultad de Ciencias Básicas Universidad de MedellínMedellinColombia

We present a theoretical study on the e.f.cts of intense laser field(ILf)and static electric field on the linear and nonlinear optical properties of a cylindrical quantum dot with Rosen-Morse axial potential under the.f.amework of e.f.ctive mass and parabolic band *** study also takes into account the e.f.cts of the structure parameters(η,V1,and R).The analytical expressions of the linear,third-order nonlinear and total optical absorption coe.f.cients(TOACs)and the relative refractive index changes(RRICs)are obtained by using the compact-densitymatrix *** results of numerical calculations show that the resonant peak position of the TOACs and RRICs shifts towards lower energies and the magnitude of the peak increases with the e.f.ct of the static electric field and *** addition,it is observed that while the resonant energies of the TOACs and RRICs of system shift towards the higher(lower)energies with the enhancement ofη,V1,they decrease with the augmentation of ***,the.f.ndings of this study show that the optical properties of the structure can be adjusted by changing the magnitude of structure parameters and applied external fields.

关键词： cylindrical quantum dot nonlinear optical response intense laser field electric field

采用内标光谱分析法测定土壤和水系沉积物中的微迹元素

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国外地质勘探技术 1980年第12期 54-58页

作者： Ciuft, e.f. 孙焕振

本文叙述了在土壤和水系沉积物中分析Pb、Zn、Co、cu、Ni、V和Cr的一种用Lu和Cd作内标的比较快速的定量光谱分析方法。锌在低浓度时通常用光谱法测定是有困难的,但它可以在纯氩气氛中进行测定。本法采用一种新的气体转换技术使其他元素... 详细信息

本文叙述了在土壤和水系沉积物中分析Pb、Zn、Co、cu、Ni、V和Cr的一种用Lu和Cd作内标的比较快速的定量光谱分析方法。锌在低浓度时通常用光谱法测定是有困难的,但它可以在纯氩气氛中进行测定。本法采用一种新的气体转换技术使其他元素也可以在同一次弧烧中进行测定。本法的效率大致为每人每小时可作7个样品的分析,每个样品测定7个元素,即每小时能作49个元素的测定。本法的速度较比色法或采用外标目视估读的半定量法快而且具有更好的定量性。

关键词：内标水系沉积物