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Journal of Hydrodynamics 2000年第4期12卷 26-35页

作者： Su Xiao bin, Wei Gang Hydrodynamics Department of Meteorology college, p. L. A. University of Science and Engineering. Nanjing, 211101, p.R.china (Received dec.1, 1999) Hydrodynamics Dep. Meteorology Coll. PLA Univ. of Sci. and Eng. Nanjing 211101 China

Three dimensional structure of baroclinic wavy jet was experimentally studied in rotating annulus subject to a negative radial temperature gradient. General features of wavy surface jet in the system were obtained. Based on the precise measurements of velocity distribution of the jet with LDV and the three dimensional temperature field in the convective system, three dimensional thermodynamic structures of jet were gained, and by using a correlation of three dimensional disturbed temperature, the unstable mechanism of disturbed temperature of baroclinic fluid in a rotating system was further discussed.

关键词： baroclinic wave rotating fluid jet correlation coefficien8

Mixed iridium-nickel oxides supported on antimony-doped tin oxide as highly efficient and stable acidic oxygen evolution catalysts

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Materials Futures 2024年第1期3卷 165-180页

作者： Jonathan Ruiz Esquius Alec p LaGrow Haiyan Jin Zhipeng Yu Ana Araujo Rita Marques Adélio Mendes Lifeng Liu clean Energy cluster International Iberian Nanotechnology LaboratoryAv.Mestre JoséVeigaBraga 4715-330Portugal carbon Science and Technology Institute INCAR-CSICFrancisco Pintado Fe 26Oviedo 33011Spain Scientific Imaging Section Okinawa Institute of Science and Technology Graduate UniversityKunigami-gunOkinawa 904-0412Japan Songshan Lake Materials Laboratory Dongguan 523808People’s Republic of China Laboratory for process Engineering EnvironmentBiotechnology and EnergyFaculty of EngineeringUniversity of PortoRua Dr Roberto FriasPorto 4200-465Portugal Associate Laboratory in chemical Engineering Faculty of EngineeringUniversity of PortoRua Dr Roberto FriasPorto 4200-465Portugal.

proton exchange membrane(pEM)water electrolysis represents a promising technology for green hydrogen production,but its widespread deployment is greatly hindered by the indispensable usage of platinum group metal catalysts,especially iridium(Ir)based materials for the energy-demanding oxygen evolution reaction(OER).Herein,we report a new sequential precipitation approach to the synthesis of mixed Ir-nickel(Ni)oxy-hydroxide supported on antimony-doped tin oxide(ATO)nanoparticles(IrNiyO_(x)/ATO,20 wt.%(Ir+Ni),y=0,1,2,and 3),aiming to reduce the utilisation of scarce and precious Ir while maintaining its good acidic OER *** tested in strongly acidic electrolyte(0.1 M HclO_(4)),the optimised IrNi1Ox/ATO shows a mass activity of 1.0 mAµgIr^(−1) and a large turnover frequency of 123 s^(−1) at an overpotential of 350 mV,as well as a comparatively small Tafel slope of 50 mV dec^(−1),better than the IrOx/ATO control,particularly with a markedly reduced Ir loading of only 19.7µgIr cm^(−2).Importantly,IrNi1O_(x)/ATO also exhibits substantially better catalytic stability than other reference catalysts,able to continuously catalyse acidic OER at 10 mA cm^(−2) for 15 h without obvious *** in-situ synchrotron-based x-ray absorption spectroscopy confirmed that the Ir^(3+)/Ir^(4+)species are the active sites for the acidic ***,the performance of IrNi1Ox/ATO was also preliminarily evaluated in a membrane electrode assembly,which shows better activity and stability than other reference *** IrNi1Ox/ATO reported in this work is a promising alternative to commercial IrO_(2) based catalysts for pEM electrolysis.

关键词： mixed oxides oxygen evolution reaction polymer electrolyte membrane antimony doped tin oxide membrane electrode assembly

NUMERIcAL SIMULATION OF HUMAN AIR BREATHING NEAR THE NOSE OUTLET

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Journal of Hydrodynamics 1999年第3期11卷 105-110页

作者： Ma Heng Buji people′s Hospital, Shengzhen 518112, p.R.china An Yi ran, Zhuang Ning Department of Mechanics, peking University, Beijing 100871, p.R.china Yan Dong Beijing Zhongguancun Hospital, Beijing 100080, p.R.china (Received dec. 30, 1998

Numerical method is used to simulate the air breathing near the outlet of human nose. The process of breathing is visualized. The distribution of the exhausted air density may be useful in designing the medical equipm... 详细信息

关键词： human breathing N S equations air refreshing

chronic effect of endosulfan on the testicular functions of rat

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Asian Journal of Andrology 1999年第4期1卷 203-206页

作者： K.c.chitra c.Latchoumycandane p.p.Mathur School of Life Sciences Pondicherry University Pondicherry 605 014 IndiaSchool of Life Sciences Pondicherry University Pondicherry 605 014 IndiaSchool of Life Sciences Pondicherry University Pondicherry 605 014 India

Aim: To find out the toxic effect of endosulfan on the testicular function of pubertal rats. Methods: Male rats of pu-bertal age were orally administered endosulfan at a dose of 1.0 mg/kg body weight for 30 days. Twenty-four hours af-ter the last treatment, the rats were sacrificed and the testis, epididymis, seminal vesicles and ventral prostate were re-moved and weighed. A 10 % testicular homogenate was prepared for biochemical estimations. Results: In endosul-fan-treated rats, there were a reduction in the body weight and the weights of testis and accessory sex organs, a de-crease in the testicular lactate and pyruvate activities, and in the testicular DNA and RNA concentrations, whereas thetesticular protein concentration was slightly increased; the specific activity of testicular steroidogenic enzyme, 3β-OH-steroid dehydrogenase and the ascorbic acid level were decreased, which were correlated with a decrease in steroidoge-nesis. The lysosomal enzyme acid phosphatase and brash-border enzyme alkaline phosphatase activities were also de-creased in the testis of treated rats. conclusion: In pubertal rats, endosulfan treatment inhibits the testicular functions.(Asian J Androl 1999 dec; 1: 203-206)

关键词： pesticides endosulfan testis steroidogenesis rats estrogens

Formation of self-assembled nanodomain structures in single crystals of uniaxial ferroelectrics lithium niobate, lithium tantalate and strontium–barium niobate

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Journal of Advanced Dielectrics 2014年第1期4卷 87-94页

作者： V.Ya.Shur V.A.Shikhova p.S.Zelenovskiy D.V.pelegov L.I.Ivleva J.dec Ferroelectric Laboratory Institute of Natural Sciences Ural Federal University51 Lenin Ave.Ekaterinburg 620000Russia General physics Institute of the Russian Academy of Sciences 38 Vavilov Str. Moscow 119991Russia Institute of Materials Science University of Silesia4 Uniwersytecka Str.Katowice PL-40-007Poland

The formation and evolution of the self-assembled nanodomain structures during polarization reversal have been comparatively analyzed in single crystals of various uniaxial ferroelectrics:LiNbO_(3)(LN),LiTaO_(3)(LT)and Sr_(x)Ba_(1-x)Nb_(2)O_(6)(SBN).Several experimental methods have been used for visualization of the micro-and nanodomain *** static domain images have been obtained by optical microscopy and piezoresponse force *** Raman confocal microscopy allowed us to obtain the domain images in the *** equilibrium slow switching with effective screening resulted in growth of polygon-shaped microdomains:hexagons in LN,triangles in LT and squares in SBN,which corresponds to crystal *** in nonequilibrium conditions(noneffective screening of depolarization field)brings to appearance of similar nanodomain structures in all studied crystals as a result of different processes:(1)formation of nanodomain ensembles,(2)discrete switching,(3)incomplete merging and(4)spontaneous backswitching.

关键词： Nanodomain structures self-assembling lithium niobate lithium tantalate strontium-barium niobate.

Research on the UV Dielectric coatings with High Damage Threshold

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chinese Journal of Lasers 1997年第3期 38-46页

作者： GAO Huailin SHAN Yusheng WANG Naiyan(china Institute of Atomic Energy, p.O.Box 2757, Beijing 102413, china)Received Oct. 21 1996 Revised manuscript received dec.16 1996

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关键词： KrF laser UV delectric coating damage threshold

Saturable Excited State Absorption of cr4+ : YAG for Q-switching Nd : YAG Laser

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chinese Journal of Lasers 1997年第3期 2-6页

作者： WAN Xiaoke LIN Lihuang OUYANG Bin DING YanhuaXU Jun DENG peizhen(Shanghai Institute of Optics & Fine Mechanics, chinese Academy of Sciences pOBox 800211, Shanghai 201800)Received Nov 8 1996 Revised manuscript received dec13 1996

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ＳａｔｕｒａｂｌｅＥｘｃｉｔｅｄＳｔａｔｅＡｂｓｏｒｐｔｉｏｎｏｆＣｒ４＋ＹＡＧｆｏｒＱ┐ｓｗｉｔｃｈｉｎｇＮｄＹＡＧＬａｓｅｒＷＡＮＸｉａｏｋｅＬＩＮＬｉｈｕａｎｇＯＵＹＡＮＧＢｉｎＤＩＮＧＹａｎｈｕａＸＵＪｕｎＤＥＮＧＰｅｉｚｈｅｎ（Ｓｈａｎｇ...

关键词： cr~4+∶YAG ESA Qswitching

Dark current suppression in HOT LWIR HgcdTe heterostructures operating in non-equilibrium mode

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红外与毫米波学报 2015年第4期34卷 385-390页

作者： Martyniuk p Gawron W pawluczyk J Keblowski A Madejczyk p Rogalski A Institute of Applied physics Military University of Technology2 Kaliskieg0 Str. 00-908 Warsaw Poland Vigo System S. A. 129/133 Poznaflska Str. 05-850 O z ar6w Mazowiecki Poland

Typically,infrared detectors require cryogenic cooling to limit dark current w hich is directly dependent on Auger generation-recombination mechanism and highly influential in Hg cd Te-narrow band gap *** Auger suppressed architectures have an advantage over conventional detectors allow ing operation at elevated temperatures>200 *** w ith combination of exclusion and extraction heterojunctions has been proposed to low er Auger *** paper presents a new long-w ave(≈10μm)infrared Hg cd Te architecture w ith graded gap/doping interfaces and extra barrier located in exclusion heterojunction to suppress dark current for high operating temperature *** barrier implementation reduces dark current by more than 20 A/cm2for room temperature operation.

关键词：红外技术毫米波技术光电技术应用

Xenoesterogens and male infertility:myth or reality?

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Asian Journal of Andrology 2000年第4期2卷 263-269页

作者： Roya Rozati p.p.Reddy p.Reddanna Rubina Mujtaba Assisted conception Services Unit Mahavir Hospital and Research Centre Hyderabad(A. P.) 500 028 IndiaInstitute of Genetics and Hospital for Genetic Diseases Hyderabad IndiaDepartment of Animal Sciences School of Life Sciences University of Hyderabad IndiaAssisted Conception Services Unit Mahavir Hospital and Research Centre Hyderabad(A. P.) 500 028 India

Aim: To evaluate the role of polychlorinated biphenyls (pcBs) as a potential environmental hazard in the deteriora-tion of male fertility. Methods: Fifty-three males were studied. After a thorough case history evaluation and rele-vant clinical and laboratory investigations, pcBs were estimated in the seminal plasma of 21 infertile men with 'Unex-plained Male Factor' and 32 fertile controls. peak retention times of the eluants were compared with those of the com-mercially available standard pcB Mix, and the results confirmed spectrophotometrically. Seminal pcB concentrafonswere compared between i) fertile and infertile men and ii) men from different areas and diets. The relationship betweenpcB concentrations and measures of sperm quality such as the total motile sperm count, was assessed. Results:pcBs were detected in seminal plasma of infertile men but absent from controls. Sperm quantity and quality were sig-nificantly lower in infertile men compared to controls. The highest average pcB concentrations were found in fish-eat-ing urban dwellers, and followed in succession by fish-eating rural dwellers, non fish-eating urban dwellers and nonfish-eating mral dwellers. The total motile sperm counts were inversely proportional to the pcB concentrations and weresignificantly lower than those of the respective controls. conclusion: pcBs may be instrumental in the deteriorationof sperm quantity and quality, a contaminated fish diet being the main source of exposure.(Asian J Androl 2000 dec; 2: 263-269 )

关键词： polychlorinated biphenyls xenoestrogens male infertility sperm

INcORpORATING MULTIpLE-HMM AcOUSTIc MODELING IN A MODULAR LARGE VOcABULARY SpEEcH REcOGNITION SYSTEM IN TELEpHONE ENVIRONMENT

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INCORPORATING MULTIPLE-HMM ACOUSTIC MODELING IN A MODULAR LA...