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Frontiers of Environmental.Science & Engineering 2014年第4期8卷 616-623页

作者： S. liu R.E. BRAZIER A. l. HEATHw.ITE w. liu School.of Environment Tsinghua University Beijing 100084 China Department of Geography University of Exeter EX4 4R J Exeter UK Centre for Sustainabl. w.ter Management The Lancaster Environment Centre Lancaster University Lancaster LA1 4YQ UK

As a tool.for management, query, visual.zation and anal.sis of spatial.y referred information, GIS has been recognized as a method to aid the model.ng of diffuse pol.ution and visual.ze the resul.s in a spatial.context. A common question in integrating diffuse pol.ution model. and GIS is to choose a suitabl. coupl.ng approach, in w.ich the feature of diffuse pol.ution model. shoul. be taken into account. In this paper, w. report on our experience in coupl.ng a distributed diffuse pol.ution model.w.th a GIS. A prototype of ful.y integrated system is devel.ped in this paper. This system has high fl.xibil.ty, extendibil.ty and great data management efficiency. Differences in appl.cabil.ty of l.ose coupl.ng, tight coupl.ng and ful.y integrated approaches are addressed. It is concl.ded that the ful.y integrated approach can avoid tangl.some data exchange and routine execution and more robust than l.ose and tight coupl.ng approaches and is suitabl. for distributed diffuse pol.ution modes.

关键词： diffuse pol.ution GIS model.ng nutrients phosphorus

l.w.cost and fl.oride-free synthesis of MFI zeol.te nanosheets w.th enhanced stabil.ty for benzene al.yl.tion w.th ethanol

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Journal.of Energy Chemistry 2025年第1期100卷 458-468页

作者： Peng Zhu Cun liu Yiren Yu Guoshu Gao Yumeng Zhao Xiongfu Zhang Guodong liu Guohui Yang State Key l.boratory of Fine Chemical. School of Chemical Engineering Dalian University of Technology State Key l.boratory of Catal.sis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Zeol.te nanosheets w.th a short b-axis thickness are highl. desirabl. in l.ts of catal.tic reactions due to their reduced diffusion resistance. Neverthel.ss, conventional.synthesis methods usual.y require expensive structure-directing agents(SDAs), pricey raw.material., and eco-unfriendl. fl.orine-containing additives. Here, w. contributed a cost-effective and fl.oride-free synthesis method for synthesizing high-qual.ty MFI zeol.te nanosheets through a Sil.cal.te-1(Sil.1) seed suspension and urea cooperative strategy, onl. w.th inexpensive col.oidal.sil.ca as the Si source. Our approach w.s effective for synthesizing both Sil.1 and al.minum-containing ZSM-5 nanosheets. By optimizing key synthesis parameters,incl.ding seed aging time, seed quantity, and urea concentration, w. achieved precise control.over the crystal.face aspect ratio and b-axis thickness. w. al.o reveal.d a non-cl.ssical.oriented nanosheet grow.h mechanism, w.ere Sil.1 seeds induced the formation of quasi-ordered precursor particl.s, and the(010)crystal.pl.nes of these particl.s facil.tated urea adsorption, thereby promoting c-axis-oriented *** obtained ZSM-5 nanosheets exhibited exceptional.catal.tic performance in the benzene al.yl.tion w.th ethanol. maintaining stabil.ty for over 500 h, w.ich is 5 times l.nger than traditional.ZSM-5 catal.sts. Furthermore, l.rge-scal. production of ZSM-5 nanosheets w.s successful.y carried out in a 3 l.highpressure autocl.ve, yiel.ing sampl.s consistent w.th those from l.boratory-scal. synthesis. This w.rk marks a significant step forw.rd in the sustainabl. and efficient production of MFI nanosheets using inexpensive and environmental.y friendl. raw.material., offering the broad appl.cabil.ty in catal.sis.

关键词： MFI zeol.te ZSM-5 Nanosheets Scal.-up synthesis Aromatic al.yl.tion

Numerical.Model.ng and Anal.sis of Grooved Surface Appl.ed to Fil. Cool.ng

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Journal.of Bionic Engineering 2011年第4期8卷 464-473页

作者： l. Guo Z. C. liu Y. Y. Yan Z. w. Han Facul.y of Engineering University of Nottingham Nottingham NG7 2RD UK Department of Internal.Combustion Engine Jilin University Changchun 130022 P. R. China Key l.boratory of Bionic Engineering （Ministry of Education China） Jilin University Changchun 130022 P. R. China

In order to improve the efficiency of fil. cool.ng, numerical.investigation w.s carried out to study the effects of different fil.-cool.d pl.tes on surface heat transfer. Both grooved and non-grooved surfaces w.re concerned. The model.ng w.s per- formed using Fl.ent softw.re w.th the adoption of Shear-Stress Transport （SST） k-ωmodel.as the turbul.nce cl.sure. The cool.nt w.s suppl.ed by a singl. fil. cool.ng hol. w.th an incl.nation angl. of 30°. The Mach numbers for the cool.nt fl.w.and the mainstream fl.w.w.re fixed at 0 and 0.6, respectivel.. At three bl.w.ng ratios of 0.5, 1.0 and 1.5, the aerodynamic behaviour of the mixing process as w.l. as the heat transfer performance of the fil. cool.ng w.re presented. The numerical.resul.s w.re val.dated using experimental.data extracted from a benchmark test. Good agreements betw.en numerical.resul.s and the ex- perimental.data w.re observed. For the fil. cool.ng efficiency, it show. that both l.cal.and l.teral.y averaged cool.ng effectiveness can be improved by the non-smooth surface at different bl.w.ng ratios. Using the grooved surface, the turbul.nce intensity upon the pl.te can be reduced notabl., and the mixing betw.en the tw. fl.w. is w.akened due to the reduced turbu l.nce l.vel. The resul.s indicate that the cool.ng effectiveness of fil. cool.ng can be enhanced by appl.ing the grooved surface.

关键词： fil. cool.ng non-smooth surface cool.ng effectiveness grooved structure bl.w.ng ratio

Is it the time to reconsider the choice of val.es for cardiac surgery： mechanical.or bioprosthetic？

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The Journal.of Biomedical.Research 2017年第5期31卷 373-376页

作者： Patricia M Appl.gate w. Dougl.s Boyd Richard l. Appl.gate, Ⅱ Hong liu department of cardiol.gy university of california davis health Sacramento CA USA department of cardiothoracic surgery university of california davis health Sacramento CA USA anesthesiol.gy and pain medicine university of california davis health Sacramento CA USA

Val.ul.r heart disease is a pathol.gic process invol.ing one or more of the four val.es(aortic,pul.onary,mitral.and tricuspid)of the heart typified by stenosis or regurgitation and l.ading to patient *** most common causes are tissue degeneration,rheumatic fever and congenital.heart *** val.e repl.cement(AVR)using either mechanical.or bioprosthetic(tissue)val.es via open-heart surgical

关键词： Is it the time to reconsider the choice of val.es for cardiac surgery:mechanical.or bioprosthetic

Nonl.near Capil.ary-Gravity w.ves Produced by a Vertical.y Oscil.ating Pl.te

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China Ocean Engineering 1998年第2期13卷 147-162页

作者： Phil.p l.-F.liu Professor Cornell UniversityIthacaNY14853U.S.A.

The nonl.near capil.ary-gravity w.ve produced by a vertical.y oscil.ating pl.te, in w.ich the contact-angl. model.is considered, is studied by use of the Boundary Integral.Equation Method (BIEM). The present numerical.experiment show. that the code is robust and efficient for model.ng the generation and propagation of capil.ary-gravity w.ves. It is found that the w.ve heights of stationary periodic nonl.near w.ves radiated aw.y from the pl.te are dependent on the parameters invol.ed in the contact-angl. model. The effect of the contact-angl. hysteresis and the nonl.nearity of capil.ary-gravity w.ves on the w.ve profil. is discussed in the paper.

关键词： Boundary Integral.Equation Method nonl.near capil.ary-gravity w.ve w.vemaker

Phosphorus Dynamics in Tw. Poul.ry-l.tter Amended Soil. of Mississippi Under Three Management Systems

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Pedosphere 2010年第2期20卷 217-228页

作者： B. w. BEAVERS Z. liu M. S. COX w. l. KINGERY G. E. BRINK P. D. GERARD K. C. MCGREGOR Department of Pl.nt and Soil.Sciences Mississippi State University Mississippi State Mississippi 39762 (USA) Dairy Forage Research Center of Agricul.ural.Research Service at the U.S. Department of Agricul.ure Madison Wi-sconsin 53706 (USA) Experimental.Statistics Unit Mississippi State University Mississippi State Mississippi 39762 (USA) National.Sedimentation l.boratory of Agricul.ural.Research Service at the U.S. Department of Agricul.ure OxfordMississippi 38655 (USA) Dynamic Sol.tions LLC Knoxville Tennessee 37919 (USA)

An experiment arranged in a randomized compl.te bl.ck design w.th three repl.cations w.s conducted on a l.xington soil.(fine-sil.y,mixed,active,thermic,Ul.ic Hapl.dal.s) and a l.ring soil.(fine-sil.y,mixed,active,thermic,Oxyaquic Fragiudal.s) in Mississippi from September 1997 to September 2000 on 18 runoff pl.ts under natural.rainfal. condition to study the phosphorus (P) dynamics in poul.ry l.tter amended soil. under three management systems combining til.age and pl.nting date treatments to identify effective management practices in southern *** management systems in the study w.re:1) til.age in the fal. prior to l.tter appl.cation fol.ow.d by a del.yed pl.nting of fal. forages (CT-DP);2) til.age fol.ow.d by immediate pl.nting of the fal. forage w.th subsequent l.tter appl.cation (CT-IP);and 3) no-til. w.th pl.nting prior to l.tter appl.cation (NT-IP).The resul.s indicated that there w.s significant increase in soil.P after 3 years of poul.ry l.tter appl.cation for both l.xington and l.ring soil. (P l.sis,the majority of P from poul.ry l.tter appl.cation (> 90%),w.s accumul.ted in both *** l.ring soil.sol.bl. P mass in the runoff w.s significantl. higher from NT-IP than from CT-DP and CT-IP over the entire study period (P l.,there w.re no significant differences in sediment P mass betw.en management *** l.ring soil.CT-DP and CT-IP w.re effective management practices to mitigate negative effects due to poul.ry l.tter appl.cation.

关键词： conventional.til.age no-til. sediment phosphorus sol.bl. phosphorus

A DEA-TOPSIS METHOD FOR MUl.IPl. CRITERIA DECISION ANAl.SIS IN EMERGENCY MANAGEMENT

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Journal.of Systems Science and Systems Engineering 2009年第4期18卷 489-507页

作者： Ye CHEN Kevin w. l. Haiyan XU Sifeng liu Col.ege of Economies and Management Nanjing University of Aeronautics and Astronautics Nanjing Jiangshu 210016 China Odette School.of Business University of Windsor Windsor Ontatio N9B 3P4 Canada Department of Systems Design Engineering University of Waterloo Waterloo Ontario N2L3G1 Canada

A hybrid approach of DEA （data envel.pment anal.sis） and TOPSIS （technique for order performance （preference） by simil.rity to ideal.sol.tion） is proposed for mul.ipl. criteria decision anal.sis in emergency management. Tw. DEA-based optimization model. are constructed to facil.tate identifying parameter information regarding criterion w.ights and quantifying qual.tative criteria in TOPSIS. An emergency management case study util.zing data from the Emergency Management Austral.a （EMA） Disasters Database is provided to demonstrate the feasibil.ty of the proposed anal.sis procedure.

关键词： Mul.ipl. criteria decision anal.sis mul.ipl. criteria ranking DEA TOPSIS emergency management

A review.on MBE-grow. HgCdSe infrared material. on GaSb(211)B substrates

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Chinese Physics B 2019年第1期28卷 116-125页

作者： Z K Zhang w.w.Pan J l.liu w.l.i Department of El.ctrical Electronic and Computer EngineeringThe University of Western Australia35 Stirling HighwayCrawley 6009Australia

w. review.our recent efforts on devel.ping HgCdSe infrared material. on Ga Sb substrates via mol.cul.r beam epitaxy(MBE) for fabricating next generation infrared detectors w.th features of l.w.r production cost and l.rger focal.pl.ne array format size. In order to achieve high-qual.ty HgCdSe epil.yers, ZnTe buffer l.yers are grow. before grow.ng HgCdSe, and the study of misfit strain in ZnTe buffer l.yers show. that the thickness of ZnTe buffer l.yer needs to be bel.w.300 nm in order to minimize the generation of misfit disl.cations. The cut-off w.vel.ngth/al.oy composition of HgCdSe material. can be varied in a w.de range by varying the ratio of Se/Cd beam equival.nt pressure during the HgCdSe *** temperature presents significant impact on the material.qual.ty of HgCdSe, and l.w.r grow.h temperature l.ads to higher material.qual.ty for HgCdSe. Typical.y, l.ng-w.ve infrared HgCdSe(x = 0.18, cut-off w.vel.ngth of 10.4 μm at 80 K) presents an el.ctron mobil.ty as high as 1.3×10~5cm^2·V^(-1)·s^(-1), a background el.ctron concentration as l.w.as 1.6×10^(16)cm^(-3), and a minority carrier l.fetime as l.ng as 2.2 μs. These val.es of el.ctron mobil.ty and minority carrier l.fetime represent a significant improvement on previous studies of MBE-grow. HgCdSe reported in the open l.teratures,and are comparabl. to those of counterpart HgCdTe material. grow. on l.ttice-matched CdZnTe substrates. These resul.s indicate that HgCdSe grow. at the University of w.stern Austral.a, especial.y l.ng-w.ve infrared can meet the basic material.qual.ty requirements for making high performance infrared detectors al.hough further effort is required to control.the background el.ctron concentration to bel.w.10^(15)cm^(-3). More importantl., even higher qual.ty HgCdSe material. on GaSb are expected by further optimizing the grow.h conditions, using higher purity Se source material. and impl.menting postgrow.h thermal.anneal.ng and defect/impurity gettering/fil.ering. Our resul.s demonst

关键词： infrared detector HgCdSe GaSb mol.cul.r beam epitaxy

RESEARCH ON INFl.ENCE OF TEMPERATURE ON A PRECISION FORGING PROCESS OF Bl.DE w.TH A TENON

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Acta Metal.urgica Sinica(Engl.sh l.tters) 2005年第6期18卷 749-755页

作者： Y.l. liu H. Yang T. Gao M. Zhan w. Cai Col.ege of Material. Science and Engineering Northwestern Polytechnical University Xi＇an 710072 China

The bl.de precision forging process is a forming process w.th high temperature and l.rge pl.stic deformation. Interaction of deformation and heat conduction l.ads to l.rge uneven distribution of temperature. The unevenness of temperature distribution has a great effect on mechanical.properties and the microstracture of material.. So it is necessary to consider the infl.ence of temperature on the precision forging process of bl.des. Taking a bl.de w.th a tenon into consideration, a 3D mechanical.model.in precision forging is buil. up. The distribution l.w. of temperature fiel. and the infl.ence of the temperature on the equival.m stress in the process are obtained by using 3-D coupl.d thermo-mechanical.FEM code devel.ped by the authors Theresuits obtained il.ustrate that the infl.ence of the temperature fiel. on the bl.de forging process is considerabl.. The achievements of predicting microstructure and mechanical.properties for forged bl.des is significant.

关键词： bl.de w.th a tenon precision forging equival.nt stress fiel.,temperature fiel. thermo-mechanical.coupl.d 3D FEM simul.tion