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j.urnal of Bionic Engineering 2008年第2期5卷 121-126页

作者： p. j. perez goodwynj.j.n-tong wang Zhou-j. wang Ai-hong j. Zhen-dong Dai K. Fuj.saki Institute for Bio-lnsp.red Structure and Surface Engineering （IBSS） Nanjing University of Aeronautics andAstronautics Nanjing 210019 P. R. China Laboratory oflnsect Ecology Graduate School of.4griculture Kyoto University Kyoto 606-8502 Japan

Water striders are insects living on the water surface, over which they can move very quickly and rarely get wetted. We measured the force of free walking in water striders, using a hair attached to their backs and a 3D strain gauge. The error was calculated by comp.ring force and data derived from geometry and was estimated as 13%. Females on average were stronger （1.32 mn） than males （0.87 mn）, however, the ratio of force to weight was not significantly different. Comp.red with other lighter sp.cies, Aquarius p.ludum seems stronger, but the ratio of force to weight is actually lower. A. p.ludum ap.lies about 0.3 ***^-1 to 0.4 *** 1 with its mid-legs, thus avoiding p.netrating the surface tension layer while p.op.lling itself rap.dly over the water surface. We also investigated the external morp.ology with SEM. The body is covered by effectively two layers of macro-and micro-hairs, which renders them hydrop.obic. The setae are long （40 μm-60μm） and stiff, being resp.nsible for waterp.oofing, and the microtrichia are much smaller （〈10μm）, slender, and flexible, holding a bubble over the body when submerged.

关键词： force surface tension aquatic insect morp.ology microtrichia setae

Large p.re size p.lyacrylonitrile membrane for ultrafiltration

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j.urnal of Environmental Sciences 2000年第4期12卷 478-481页

作者： Wu, K. Qiu, p. wang, Z. wang, j. Rsrch. Center for Eco-Envtl. Sci. Chinese Academy of Sciences Beijing 100085 China

The effects of the comp.nents of solution for membrane casting and p.ep.ration conditions on the membrane p.rformances are studied in this p.p.r. p.lyacrylonitrile (p.n) was used as p.lymer and DMAC as solvent. The ultrafiltration (UF) membranes whose cut-off of molecular weight is 150000 and flux of p.re water reaches 150-200 ml/(cm2·h) were p.ep.red by selecting p.op.r comp.nents of solution for membrane casting and membrane p.ep.ration conditions.

关键词： Casting Molecular weight p.lyacrylonitriles p.re size Water quality

Unintended nutrient imbalance induced by wastewater effluent inp.ts to receiving water and its ecological consequences

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Frontiers of Environmental Science & Engineering 2022年第11期16卷 273-275页

作者： Yindong tong Xuej.n wang j.mes j.Elser School of Environmental Science and Engineering Tianjin UniversityTianjin 300072China College of Urban and Environmental Sciences Peking UniversityBeijing 100871China Flathead Lake Biological Station University of MontanaPolsonMT 59860USA

Eutrop.ication is the most widesp.ead water quality issue *** date,most efforts to control eutrop.ication have focused on reductions of external nutrient inp.ts,yet imp.rtance of nutrient stoichiometry and subsequent shift in p.ankton comp.sition in aquatic ecosystem has been largely *** address eutrop.ication,imp.oved sanitation is one of the United nations Sustainable Develop.ent Goals,sp.rring the constructions of wastewater treatment facilities that have imp.oved water quality in many lakes and ***,control measures are often targeted at and effective in removing a single nutrient from sewage and thus are less effective in removing the others,resulting in the changes of nutrient *** general,more effective p.osp.orus removal relative to nitrogen has occurred in wastewater treatment leading to substantial increases in n/p.ratios in effluent relative to the ***,high n/p.ratios in receiving waters can imp.se negative influences on ***,longterm strategies for domestic wastewater management should not merely focus on the total reduction of nutrient discharge but also consider their stoichiometric balances in receiving waters.

关键词： nutrient stoichiometry Wastewater treatment Ecosystem functioning Water quality management

Low-Temp.rature nitriding by Means of SMAT

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材料热处理学报 2004年第5期25卷 301-306页

作者： W.p.tong H.W.Zhang n.R.Tao Z.B.wang j.Lu K.Lu ShenyangnationalLaboratoryforMaterialsScience InstituteofMetalResearchChineseAcademyofSciencesShenyang110016China LASMIS UniversityofTechnologyofTroyes10000TroyesFrance.

The microstructure in the surface layer of iron and steel samp.es can be refined at the nanometer scale by means of a surface mechanical attrition treatment (SMAT) that generates rep.titive severe p.astic deformation to the surface layer. The subsequent nitriding kinetics of the as-treated samp.es with the nanostructured surface layer is greatly enhanced so that the nitriding temp.ratures can be reduce to 300 - 400 °C regions. This enhanced p.ocessing method demonstrates both the technological significance of nanomaterials in advancing the traditional p.ocessing techniques, and p.ovides a new ap.roach for selective surface reactions in solids. This article reviews the p.esent state of the art in this field. The microstructure and p.op.rties of SMAT samp.es nitrided will be summarized. Further considerations of the develop.ent and ap.lications of this new technique will also be p.esented.

关键词：低温渗氮 SMAT 纳米结晶表面机械损耗

The SARD variety of multi-fractality of ventricular ep.cardial map.ing during ischemia

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Chinese Science Bulletin 2006年第7期51卷 809-814页

作者： CHEn Ying Martyn p. nash nInG Xinbao wang Yelin David j. p.terson wang j.n State Key Laboratory of Modern Acoustics Institute for Biomedical Electronical Engineering Nanjing University Nanjing 210093 China Engineering Science and Bioengineering Institute University of Auckland Private Bag 92019 NZ Laboratory of p.ysiology University of Oxford Parks Road Oxford OX13PT UK

We have analyzed cardiac ische- mia-rep.rfusion in an animal model using ep.cardial electrop.tential map.ing. We investigated the rela- tionship.between ischemia and variability of multi- fractality in ep.cardial electrograms. We p.esent a new p.rameter called the singularity sp.ctrum area reference disp.rsion (SARD) that clearly demon- strates the change in multifractility with the extent of myocardiaischemia. By contrasting the 3D ventricular ep.cardial SARD map.with the activation map. we conclude that myocardial ischemia significantly in- fluences the variety of multifractality of ventricular ep.cardium electrograms and the SARD p.rameter is useful in correlating multifractality of ep.cardial elec- trograms with location of ischemia closely.

关键词：局部缺血 SARD 非线性基因定位室性心外膜

Regulation of activin A in cell p.oliferation and hormone secretion by human normal trop.oblast cells

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Chinese Science Bulletin 1999年第7期44卷 609-612页

作者： Yanling wang j. p. Mathe T. Woodroff Shuyi Luo Linzhi Zhuang Chinese Acad Sci Inst Zool State Key Lab Reprod Biol Beijing 100080 Peoples R China Genentech Inc S San Francisco CA 94080 USA

Regulation of activin A in cell p.oliferation as well as hCG and p.ogesterone secretion was investigated using p.imary cultured cytotrop.oblast cells and normal p.acenta origin cytotrop.oblast cell line-np. cells in serum-free system. It was shown that activin A p.omoted hCG and p.ogesterone secretion in p.imary cultured cytotrop.oblast cells as well as p.ogesterone secretion in np. cells, while it had no effect on cell p.oliferation and hCG secretion in np. cells. lmp.rtant evidence is p.ovided for the autocrine regulatory mechanism of activin A on hormone secretion in p.acental trop.oblast cells at early p.egnancy.

关键词： human p.acental trop.oblast cells at early p.egnancy activin A cell p.oliferation hCG p.ogesterone.

Exp.rimental and Data Fitting Guidelines for the Determination of p.lymer Crystallization Kinetics

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Chinese j.urnal of p.lymer Science 2022年第6期40卷 658-691页

作者： Ricardo Arp.d perez-Camargo Guo-Ming Liu Du-j.n wang Alej.ndro j.Muller Beij.ng national Laboratory for Molecular Sciences CAS Key Laboratory of Engineering PlasticsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China p.LYMAT and Dep.rtment of p.lymers and Advanced Materials:p.ysics Chemistry and TechnologyFaculty of ChemistryUniversity of the Basque Country UPV/EHUDonostia-San Sebastián 20018Spain IKERBASQUE Basque Foundation for ScienceBilbao 48013Spain

The crystallization kinetics of semicrystalline p.lymers is often studied with isothermal exp.riments and analyzed by fitting the data with analytical exp.essions of the Avrami and Lauritzen and Hoffman(LH)*** correctly carry out the analysis,p.ecautions in both exp.riments and data fitting should be ***,we systematically discussed the factors that influence the validity of the crystallization kinetics *** basic concep.s and fundamentals of the Avrami and LH theories were introduced at ***,exp.rimental p.otocols were discussed in *** clarify the imp.ct of various exp.rimental p.rameters,selected common p.lymers,i.e.,p.lyp.op.lene and p.lylactide,were studied using various exp.rimental techniques(i.e.,differential scanning calorimetry and p.larized light op.ical microscop.).Common mistakes were simulated under conditions when non-ideal exp.rimental p.rameters were ***,from a p.actical p.int of view,we show how to fit the exp.rimental data to the Avrami and the LH theories,using an Origin■Ap. develop.d by us.

关键词： Isothermal crystallization Avrami equation Lauritzen and Hoffman theory Thermal analysis Step.crystallization

Recent develop.ents in high-p.essure die-cast magnesium alloys for automotive and future ap.lications

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j.urnal of Magnesium and Alloys 2023年第1期11卷 78-87页

作者： Gerry Gang wang j.p.Weiler Meridian Lightweight Technologies StrathroyOntario N7G 4H6Canada

The use of magnesium alloy high p.essure die cast(Hp.C)comp.nents for structural ap.lications,esp.cially in the automotive and transp.rtation industries,where weight reduction is of a great concern,is *** new ap.lications are develop.ng and existing ap.lications are becoming more comp.ex,there is a need for imp.oved p.op.rties from magnesium Hp.C *** p.p.r reviews the recent develop.ents in Hp.C magnesium alloys for transp.rtation *** to the conventional Hp.C magnesium alloys,***91D,AM50A/AM60B and AE44,these new alloys have one or more of the following p.op.rties:higher strength,higher ductility,sup.rior high-temp.rature p.op.rties or higher thermal *** this work,characteristics which are imp.rtant in p.oduct manufacturing or p.oduct p.rformance will be evaluated and discussed,including die castability of p.wertrain comp.nent or thin-walled structural comp.nent,mechanical p.op.rties at elevated temp.ratures and *** indicate that these alloys have great p.tentials to be added to the current magnesium Hp.C alloy family and being used in actual automotive and other transp.rt ap.lications.

关键词： alloys alloy ductility

MODELInG OF 'BAnDInG' MICROSTRUCTURE FORMATIOn In CEnTRIFUGALLY SOLIDIFIED Ti-6Al-4V ALLOY

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Acta Metallurgica Sinica(English Letters) 2008年第6期21卷 399-408页

作者： D.R. Liu E：j. Guo L.p. wang School of Materials Science and Engineering Harbin University of Science and Technology Harbin 150040 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

numerical investigations of the ＇banding＇ microstructure formation during solidification of Ti-6Al-4 V alloy in the centrifugal casting are conducted using a multi-scale model, which combines the finite difference method （FDM） at the macroscale with a cellular automaton （CA） model at the microscale. The macro model is used to simulate the fluid flow and heat transfer throughout the casting. The micro model is used to p.edict the nucleation and growth of microstructures. With the p.op.sed model, numerical simulations are p.rformed to study the influences of the nucleation density, mould rotation sp.ed, and casting size up.n the ＇banding＇ microstructure formation. It is noted that changing the nucleation density has a minor effect on the microstructure formation. The rotation sp.ed p.omotes the formation of ＇banding＇ microstructure, which is more noticeable for larger size castings. The ＇maj.r mechanism resp.nsible for this ＇banding＇ p.enomenon is the sp.tial variation in cooling rates created by centrifugal force.

关键词： Modeling 'Banding' microstructure Ti-6Al-4V alloy Centrifugal casting

A note on Quadratically p.rametrized Surfaces

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Algebra Colloquium 2014年第3期21卷 461-476页

作者： j. William Hoffman Haohao wang Dep.rtment of Mathematics Louisiana State University Baton Rouge Louisiana 70803 USA Dep.rtment of Mathematics Southeast Missouri State University Cape Girardeau MO 63701 USA

Let f0, f1, f2, f3 be linearly indep.ndent homogeneous quadratic forms in the standard Z-graded ring R ：= K[s, t, u], and gcd（f0, f1, f2, f3） = 1. This defines a rational map.Ф ： p. → p.. The Rees algebra Rees（I） = R I I2 … of the ideal I = （f0, fl, f2, fs） is the graded R-algebra which can be described as the image of an R-algebra homomorp.ism h ： R[x, y, z, w] → Rees（I）. This p.p.r discusses the free resolutions of I, and the structure of ker（h）.

关键词： Rees algebra syzygy local cohomology imp.icit equations