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Clinical Application of Bioprosthesis in China:Current status and Future

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Current Medical science 2019年第4期39卷 523-525页

作者： Yin WANG Wei-wei JIANG Nian-guo d0NG department of Cardiovascular surgery Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China department of Gastroenterology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China

China is one of the countries which have a high incidence of heart valvular disease,but the use of biological valve is limited in China before because the majority of patients are young patients suffering from rheumatic heart *** biological valve has a good application prospect in *** the one hand,the new generation of biological valves have been significantly improved in the aspects of anti-calcification treatment,anti-metabolism,material quality control,valve frame mechanics design,and leaflet sewing technology,and the application effect is improved;on the other hand,surgeons should adapt to the new concept changes,and correctly understand and rationally apply biological valves,master valve repair,atrial fibrillation ablation and other techniques,combined with interventional,minimally invasive techniques,etc.,according to the specific conditions of the disease and choose the surgery type to ensure the patients5 long-term life quality.

关键词： biological valve valve surgery clinical application China

Wetting kinetics of siC nanoparticle reinforced sn-Pb eutectic solders

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China Welding 2010年第3期19卷 16-20页

作者：陈茂爱蒋元宁 d．P．sekulic 赵慧 Key Lab for Liquid-solid structure Evolution and Materials Processing（ Ministry of Education） and Institute for Materials Joining Shandong University Jinan 250061. department of Mechanical Engineering University of Kentucky Lexington KY 40506 USA. Creative Thermal solutions Inc. Urbana-Champagne IL 61802 USA.

siC nanoparticles reinforced eutectic sn-Pb solder were prepared by mechanical mixing method. Reactive wetting of the resultant composite solders on Cu substrates was investigated using real time, in-situ visualization of the triple-line movement. It was found that spreading rates of all solder pastes in this work do not obey Tanner＇ s law of non-reactive spreading. siC nano-particles slow down both the pre-melting and post-melting spreading rates of composite solder pustes. As the content of siC nano-particles increase, the melting point of composite solders decrease, and the spreading time of molten composite solder pastes increases.

关键词： wetting kinetics composite solder nanoparticle spreadability

A trap with light-emitting diode(LEd)lights:Evaluating the effect of location and orientation of lights on the catch rate of snow crab(Chionoecetes opilio)

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Aquaculture and Fisheries 2019年第6期4卷 255-260页

作者： Khanh Q.Nguyen Paul d.Winger Fisheries and Marine Institute Memorial University of Newfoundland155 Ridge RoadSt.John'sNLA1C 5R3Canada Nha Trang University 2 Nguyen Dinh ChieuNha Trang57000Viet Nam

This study investigated the effect of installing underwater light-emitting diode(LEd)lights in different locations(close and distant to the trap entrance)and orientations(normal and upside down direction)inside baited traps targeting snow crab(Chionoecetes opilio)off the coast of Newfoundland and Labrador,*** experimental treatments were evaluated in comparison with traditional baited traps(control).Our results showed each of the experimental treatments produced significantly higher(39%–57%;48%on average)catch per unit effort(CPUE)compared to the control traps,with no significant differences for both legal and sublegal-sized crab among the different experimental *** soak times significantly increased the CPUE of the illuminated traps,but did not affect the catch rate of the control *** results also indicated crab size frequency distributions were independent of experiment *** results suggest that fishing enterprises could improve their catching performance by adding LEd lights to their traps,but the location and orientation of the lights appears unimportant.

关键词： LEd Crab trap CPUE Inshore fishery Catchability

UsING LIFE CYCLE AssEssMENT METHOds TO GUIdE ARCHITECTURAL dECIsION-MAKING FOR sUsTAINABLE PREFABRICATEd MOdULAR BUILdINGs

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Journal of Green Building 2012年第3期7卷 151-170页

作者： Jeremy Faludi Michael d.Lepech George Loisos Principal Faludi Design Minneapolis College of Art&design department of Civil and Environmental Engineering Stanford University Loisos+Ubbelohde Architects

Within this work,life cycle assessment modeling is used to determine top design priorities and quantitatively inform sustainable design decision-making for a prefabricated modular building.A case-study life-cycle assessment was performed for a 5,000 ft2 prefabricated commercial building constructed in san Francisco,California,and scenario analysis was run examining the life cycle environmental impacts of various energy and material design substitutions,and a structural design *** show that even for a highly energy-efficient modular building,the top design priority is still minimizing operational energy impacts,since this strongly dominates the building life cycle’s environmental ***,as an energy-efficient building approaches net zero energy,manufacturing-phase impacts are dominant,and a new set of design priorities *** and end-of-life disposal impacts were of low to negligible importance in both cases.

关键词： life cycle assessment design priorities modular building green building priorities energy efficiency materials renewable energy

A Pt/MnV_(2)O_(6) nanocomposite for the borohydride oxidation reaction

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Journal of Energy Chemistry 2021年第4期30卷 428-436页

作者： Jadranka Milikic Marta Martins Ana s.dobrota Gamze Bozkurt Gulin s.P.soylu Ayse B.Yurtcan Natalia V.skorodumova Igor A.Pasti Biljana sljukic diogo M.F.santos Faculty of Physical Chemistry University of BelgradeStudentski trg 12-1611158 BelgradeSerbia CeFEMA Instituto Superior TécnicoUniversidade de LisboaLisbonPortugal Project Coordination Implementation and Research Center Erzurum Technical UniversityErzurumTurkey Faculty of Engineering Chemical Engineering DepartmentIstanbul University-Cerrahpasa34320 AvcilarIstanbulTurkey department of Chemical Engineering Atatürk UniversityErzurumTurkey department of Materials science and Engineering School of Industrial Engineering and ManagementKTH-Royal Institute of TechnologyBrinellvägen 2310044 StockholmSweden department of Physics and Astronomy Uppsala UniversityBox 51675120 UppsalaSweden

Problems associated with carbon support corrosion under operating fuel cell conditions require the identification of alternative supports for platinum-based nanosized *** supported on manganese vanadate(Pt/MnV_(2)O_(6))was prepared by microwave irradiation method and characterized using X-ray diffraction,Fourier-transform infrared spectroscopy,X-ray photoelectron spectroscopy,scanning electron microscopy with energy dispersive spectroscopy,and transmission electron *** borohydride oxidation reaction(BOR)on Pt/MnV_(2)O_(6) was studied in highly alkaline media using voltammetry,chronoamperometry,and electrochemical impedance *** electrocatalytic activity of Pt/MnV_(2)O_(6) was also compared with that of commercial Pt/C(46 wt%Pt)*** apparent activation energy of BOR at Pt/MnV_(2)O_(6) was estimated to be 32 k J mol^(-1) and the order of reaction to be 0.51,indicating that borohydride hydrolysis proceeds in parallel with its ***-term stability of Pt/MnV_(2)O_(6) under BOR typical conditions was observed.A laboratory-scale direct borohydride fuel cell assembled with a Pt/MnV_(2)O_(6) anode reached a specific power of 274 W g^(-1).Experimental results on Pt/MnV_(2)O_(6) were complemented by dFT calculations,which indicated good adherence of Pt to MnV_(2)O_(6),beneficial for electrocatalyst stability.

关键词： Borohydride oxidation reaction Platinum-based electrocatalyst Manganese vanadate density functional theory

On the Base Point Locus of surface Parametrizations:Formulas and Consequences

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Communications in Mathematics and statistics 2022年第4期10卷 757-783页

作者： david A.Cox sonia Pérez-díaz J.Rafael sendra department of Mathematics and statistics Amherst CollegeAmherstMA 01002USA Universidad de Alcalá Dpto.de Física y Matemáticas28871 MadridSpain

This paper shows that the multiplicity of the base point locus of a projective rational surface parametrization can be expressed as the degree of the content of a univariate *** a consequence,we get a new proof of the degree formula relating the degree of the surface,the degree of the parametrization,the base point multiplicity and the degree of the rational map induced by the *** addition,we extend both formulas to the case of dominant rational maps of the projective plane and describe how the base point loci of a parametrization and its reparametrizations are *** an application of these results,we explore how the degree of a surface reparametrization is affected by the presence of base points.

关键词： Base point Hilbert-samuel multiplicity surface parametrization Reparametrization Parametrization degree surface degree

Numerical study on static and dynamic fracture evolution around rock cavities

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Journal of Rock Mechanics and Geotechnical Engineering 2013年第4期5卷 262-276页

作者： s.Y.Wang L.sun C.Yang s.Q.Yang C.A.Tang ARC Centre of Excellence for Geotechnical science and Engineering The University of Newcastle department of Civil Engineering Catholic University of America school of Transportation Southeast University Centre for Geotechnical and Materials Modelling Department of CivilSurveying and Environmental EngineeringThe University of Newcastle state Key Laboratory for Geomechanics and deep Underground Engineering School of Mechanics and Civil EngineeringChina University of Mining and Technology school of Civil and Hydraulic Engineering Dalian University of Technology

In this paper,a numerical code,RFPA2d（rock failure process analysis）,was used to simulate the initiation and propagation of fractures around a pre-existing single cavity and multiple cavities in brittle *** static and dynamic loads were applied to the rock specimens to investigate the mechanism of fracture evolution around the cavities for different lateral pressure *** addition,characteristics of acoustic emission（AE） associated with fracture evolution were ***,the evolution and interaction of fractures between multiple cavities were investigated with consideration of stress redistribution and transference in compressive and tensile stress *** numerically simulated results reproduced primary tensile,remote,and shear crack fractures,which are in agreement with the experimental ***,numerical results suggested that both compressive and tensile waves could influence the propagation of tensile cracks;in particular,the reflected tensile wave accelerated the propagation of tensile cracks.

关键词： Cracks dynamic loading Numerical simulations Acoustic emission(AE) Heterogeneity

China＇s Macroeconomic Outlook and Risk Assessment： Counterfactual Analysis, Policy simulation, and Long-Term Governance- A summary of Annual Report （2015-2016）

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Frontiers of Economics in China-selected Publications from Chinese Universities 2016年第2期11卷 173-191页

作者： Kevin X. d. Huang Guoqiang Tian department of Economics Vanderbilt University Nashville TN 37235-1819 USA Institute for Advanced Research (IAR) Shanghai University of Finance and Economics (SUFE) Shanghai 200433 China school of Economics and Institute for Advanced Research (IAR) Shanghai University of Finance and Economics (SUFE) Shanghai 200433 China department of Economics Texas A&M University College Station TX 77843 USA

Abstract This summary report highlights the confluence of continued downward pressures and deflation scares in the face of looming uncertainty in China＇s key macroeconomic landscapes. Counterfactual analyses and policy simulations are conducted, in addition to benchmark forecasts, based on IAR-CMM model and taking into account both cyclical and secular factors. Economic deceleration is projected to continue in the short to medium term, with real GdP growth declining to 6.3% （5.5% using more reliable instead of official data） in 2016 and facing a significant risk of sliding further down in 2017. Five key factors contributing to the weak outlook, additional to frictions and impediments associated with economic transition/restructuring and lackluster domestic/external demands, are identified, including： lack of new growth/ development engine, exhaustion of government-led driving force, the crowding-out of private sectors by state-owned enterprises （sOEs） with excess capacity／capital overhang, nonperforming government sectors and officials, and twist or misinterpretation of the ＂New Normal.＂ A root cause of these problems, lying with sluggishness in China＇s transformation into a market based economy, has to do with overpowered government but underpowered market in resource allocation and government underperformance in enforcing integrity and transparency in the marketplace and in providing public goods and services. At the nexus between inclusive growth and institutional transformation are market oriented and rule of law governed structural reforms and harmonious development. As such, fundamental institutional reforms that dialectically balance demand and supply side factors and properly weigh short run stabilization against long run development should be elevated to the top of the agenda.

关键词： macroeconomic forecast risk assessment policy simulation,alternative scenarios long-term governance

Effect of La^(3+)substitution on structural,microstructure,magnetic properties,and microwave absorbing ability of yttrium iron garnet

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Journal of Rare Earths 2023年第4期41卷 578-587页

作者： sari Hasnah dewi Ade Mulyawan Yosef sarwanto didin s.Winatapura Wisnu Ari Adi National Research and Innovation Agency Kawasan PuspiptekSerpongTangerang SelatanBanten15314Indonesia

synthesis and characterization of lanthanum-doped yttrium iro n garnet(YIG)in the compositional se ries of Y_(3-x)La_(x)Fe_(5)O_(12)(x=0.0,0.1,0.3,and 0.5)were carried *** compositions were made by using solid state reaction method with ball-milling *** phase formation,surface morphology,magnetic properties,and microwave absorbing ability of all compositions were characterized by using an X-ray diffractometer,a scanning electron microscope,a vibrating sample magnetometer,and a Vector network *** results reveal that all compositions are crystallized into Y_(3)Fe_(5)O_(12)phase(space group la-3d(230).It was observed that the lattice constant is increased from 1.2373 to 1.2421 nm with the increase of lanthanum substitution level from x=*** crystallite size of Y_(3-x)La_(x)Fe_(5)O_(12)series calculated by scherrer method is found to decrease from 78 nm in x=0.0-63 nm in x=*** particle size distribution from the surface morphology image analysis is shifted to lower-range number with the increase of lanthanum substitution level from x=0.0 to *** substitution process also affects the lattice distortion in La-doped samples and changes the bond angles and bond lengths of the YIG *** the results,a linear correlation between the Fe'-O-Fe bond angle with magnetic properties parameters of saturation magnetization(M_(s))and remanence magnetization(M_(r))was *** to the lanthanum substitution process,all La^(3+)-doped samples possess higher M_(s)and M_(r)values compared to the original *** results of Vector network analyzer show that the improvement of the M_(s)and M_(r)plays an important role in enhancing the microwave absorbing ability of the *** minimum RL changes from-8.22 dB(~85.22%microwave absorption)in x=0.0 to-14.21 dB(~96.25%microwave absorption)in x=*** enhancement is mainly ascribed to the natural magnetic resonance loss and dipoIe-polarization loss due to the substitution *** decr

关键词： Yttrium iron garnet Rare-earth doping solid-state reaction Magnetic properties structural properties Microwave absorbing ability