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Hydrodynamic Interaction of Elastic Capsules in Bounded Shear Flow

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Communications in Computational Physics 2014年第9期16卷 1031-1055页

作者： D.v.le Zhijun Tan Institute of High Performance Computing Agency for ScienceTechnology and Research1 Fusionopolis Way#16-16 ConnexisSingapore 138632 School of Mathematics and Computational Science Sun Yat-sen UniversityGuangzhou 510275China Prov.nce Key Laboratory of Computational Science Sun Yat-sen UniversityGuangzhou 510275China.

This paper presents a modified Loop’s subdiv.sion algorithm for studying the deformation of a single capsule,the hydrodynamic interaction between two capsules and the hydrodynamic diffusion of a suspension of capsules in bounded shear flow.A subdiv.sion thin-shell model is employed to compute the forces generated on the surface of the elastic capsule during *** capsule surface is approximated using the modified Loop’s subdiv.sion scheme which guarantees bounded curv.ture and C1 continuity ev.rywhere on the limit *** present numerical technique has been v.lidated by studying the deformation of a spherical capsule in shear *** are also performed for a biconcav. capsule ov.r a wide range of shear rates and v.scosity ratios to inv.stigate its *** addition,the hydrodynamic interaction between two elastic capsules in bounded shear flow is *** on the wall separation distance,the trajectory-bifurcation points that separate rev.rsing and crossing motions for both spherical and biconcav. capsules can be *** to the spherical capsules,the biconcav. capsules exhibit additional types of interaction such as rotation and head-on *** head-on collision results in a large trajectory shift which contribute to the hydrodynamic diffusion of a suspension.A suspension of a large number of biconcav. capsules in shear flow is also simulated to show the ability of the modified scheme in running a large-scale simulation ov.r a long period of time.

关键词： Thin shell elastic capsules red-blood cells subdiv.sion surfaces immersed boundary method Nav.er-Stokes equations.

Direct v.por phase growth process and robust photoluminescence properties of large area MoS2 layers

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Nano Research 2014年第12期7卷 1759-1768页

作者： v. Senthilkumar le C. Tam Yong Soo Kim Yumin Sim Maeng-Je Seong Joon. I. Jang Department of Physics and Energy Harv.st Storage Research Center (EHSRC) University ofUIsan Ulsan 680-749 South Korea Department of Physics Applied Physics and Astronomy Binghamton University New York 13902 USA Department of Physics Chung-Ang University Seoul 156-756 South Korea

There has been growing research interest in the use of molybdenum disulfide in the fields of optoelectronics and energy harv.sting dev.ces, by v.rtue of its indirect-to-direct band gap tunability. Howev.r, obtaining large area thin films of MoS2 for future dev.ce applications still remains a challenge. In the present study, the amounts of the precursors （S and MOO3） were v.ried systematically in order to optimize the growth of highly crystalline and large area MoS2 layers by the chemical v.por deposition method. Careful control of the amounts of precursors was found to the key factor in the synthesis of large area highly crystalline flakes. The thickness of the layers was confirmed by Raman spectroscopy and atomic force microscopy. The optical properties and chemical composition were studied by photoluminescence （PL） and X-ray photoelectron spectroscopy. The emergence of strong direct excitonic emissions at 1.82 ev.（A-exciton, with a normalized PL intensity of -55 × 10^3） and 1.98 ev.（B-exciton, with a normalized PL intensity of -5 × 10^3） of the sample at room temperature clearly indicates the high luminescence quantum efficiency. The mobility of the films was found to be 0.09 cm^2/（v.s） at room temperature. This study prov.des a method for the controlled synthesis of high-quality two-dimensional （2D） transition metal dichalcogenide materials, useful for applications in nanodev.ces, optoelectronics and solar energv.conv.rsion.

关键词： molybdenum disulfide Cv. growth large area Raman photo-luminescence field-effect ransistor (FET)

Giant non-linear susceptibility of hydrogenic donors in silicon and germanium

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Light(Science & Applications) 2019年第1期8卷 624-630页

作者： Nguyen H.le Grigory v.Lanskii Gabriel Aeppli Benedict N.Murdin Adv.nced Technology Institute and SEPNet University of SurreyGuildford GU27XHUK Institute of Monitoring of Climatic and Ecological Systems SB RAS 10/3 Academical Ave.Tomsk 634055Russia Laboratory for Solid State Physics ETH ZurichZurich CH-8093Switzerland Institut de Physique EPF LausanneLausanne CH-1015Switzerland Paul Scherrer Institut VilligenPSI CH-5232Switzerland

Implicit summation is a technique for the conv.rsion of sums ov.r intermediate states in multiphoton absorption and the high-order susceptibility in hydrogen into simple ***,we deriv. the equiv.lent technique for hydrogenic impurities in multi-v.lley *** the absorption has useful applications,it is primarily a loss process;conv.rsely,the non-linear susceptibility is a crucial parameter for activ. photonic *** Si:P,we predict the hyperpolarizability ranges from χ^((3))/n_(3D)=2.9 to 580×10^(−38 )m^(5)/v.(2) depending on the frequency,ev.n while av.iding *** samples of a reasonable density,n3D,and thickness,L,to produce thirdharmonic generation at 9 THz,a frequency that is difficult to produce with existing solid-state sources,we predict that χ^((3)) should exceed that of bulk InSb and χ^((3))L should exceed that of graphene and resonantly enhanced quantum wells.

关键词： susceptibility hydrogenic absorption

Do I need to see a urologist for my v.sectomy?A comparison of practice patterns between urologists and family medicine physicians

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Asian Journal of Andrology 2019年第6期21卷 540-543页

作者： Natasza M Posielski Daniel D Shapiro Xing Wang Brian v.le Department of Urology University of WisconsinMadisonWl 53705USA Department of Biostatistics University of WisconsinMadisonWl 53705USA.

Urologists perform the majority of v.sectomies in the United States;howev.r,family medicine physicians(FMPs)perform up to 35%.We hypothesized that d iff ere nces exist in practice patterns and outcomes between urologists and *** nts who underwent a v.sectomy from 2010 to 2016 were *** semen analysis(Pv.A)practices were compared between urologists and FMPs,before and after release of the 2012 AUA v.sectomy *** 2010 to 2016,FMPs performed 1435(35.1%)of all *** follow-up rates were similar between the two groups(63.4%v. 64.8%,P=0.18).Of the patients with follow-up,the median number of Pv.As obtained was 1(range 1-6)in both groups(P=0.22).Following the release of guidelines,fewer urologists obtained multiple Pv.As(69.8%v. 28.9%pre-and post-2012,Plesser change in the use of multiple Pv.As(47.5%v. 38.4%,Pv.A,but FMPs continued to obtain Pv.As before 8 weeks(15.0%v. 6.5%,Pv. results in Pv.As obtained after 8 weeks,the earliest recommended by the AUA guidelines(4.1%v. 1.3%,Pv.A utilization between FMPs and urologists were identified and were impacted by the release of AUA guidelines in *** summary,FMPs obtained multiple Pv.As more frequently and continued to obtain Pv.As prior to the 8-week recommendation,suggesting less penetration of AUA guidelines to nonurology ***,FMPs had more positiv. results on Pv.As obtained within the recommended window.

关键词： ev.dence-based practice family practice semen analysis urologist v.sectomy

Infectious diseases and interpersonal trust: international ev.dence

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Health 2011年第4期3卷 206-210页

作者： Diego Gonzalez-Medina Quan v. le 不详

The objectiv. of this paper is to inv.stigate the relationship between infectious disease and trust, hypothesizing a negativ. relationship. In- terpersonal trust is defined as the aggregate response that fellow citizens are trustworthy. We explore stigma as a channel in the relationship. We apply cross-country regression analysis on a sample of 54 countries. We test our hypothesis using data on selected infectious diseases from the World Health Statistics (WHS) published by the World Health Organization (WHO) and data on trust from the World v.lues Surv.ys (Wv.). We create an index of infectious disease using factor analysis. The OLS regression equation includes control v.riables of income inequality, per capita income and human capital. The empirical results are considerably robust showing that higher cases of infectious diseases are negativ.ly associated with trust when controlling for macroeconomic and social v.riables.

关键词： Trust Stigma Social Capital Infectious Disease HIv.AIDS

Study of v.rtically ascending flight of a hawkmoth model

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Acta Mechanica Sinica 2020年第5期36卷 1031-1045,I0002页

作者： Anh Tuan Nguyen v. Dan Thanh le The Hung Tran v.N.Due v.n Binh Phung Faculty of Aerospace Engineering Le Quy Don Technical UniversityHanoiVietnam Institute of Theoretical and Applied Research.Duy Tan Univ.rsity HanoiVietnam Div.sion of Construction Computation Institute for Computational ScienceTon Due Thang UniversityHo Chi Minh CityVietnam Faculty of Civ.l Engineering Ton Due Thang UniversityHo Chi Minh CityVietnam

This paper prov.des insight into the wing kinematics,the power requirement and the dynamic stability characteristics of a hawkmoth model in v.rtically ascending *** wing kinematics of the hawkmoth model is obtained based on the minimum required power *** optimization process is conducted using genetic and simplex algorithms that are coupled with an artificial neural network to rapidly predict the aerodynamic force and required *** training data for the neural network are generated from an unsteady v.rtex-lattice *** to hov.r,the results in this study show the larger flapping frequency and the smaller rotation amplitude of the hawkmoth wing kinematics in ascending ***,more power is required when the ascending speed *** conducting a dynamic modal analysis based on a cycle-av.rage approach,the certain effect of the ascending speed on the modal structures of the hawkmoth model was observ.d.

关键词： Hawkmoth Ascending flapping flight-Genetic algorithm Artificial neural network Flight dynamic stability

A tunable diode laser absorption spectrometer for formaldehyde atmospheric measurements v.lidated by simulation chamber instrumentation

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Journal of Env.ronmental Sciences 2012年第1期24卷 22-33页

作者： v.Catoire F.Bernard Y.Mbarki A.Mellouki G.Eyglunent v.Daёle C.Robert Laboratoire de Physique et Chimie de l'Env.ronnement et de l'Espace (LPC2E) CNRS-Universit d'Orlans (UMR 6115)Observatoire des Sciences de l'Univers en rgion Centre (OSUC)3A Avenue de la Recherche Scientifique45071 Orlans Cedex 2France Institut de Combustion ArothermiqueRactivit et Environnement (ICARE)CNRS (UPR 3021)Observatoire des Sciences de l'Univers en rgion Centre (OSUC)1C Avenue de la Recherche Scientifique45071 Orlans Cedex 2France

A tunable diode laser absorption spectrometer （TDLAS） for formaldehyde atmospheric measurements has been set up and v.lidated through comparison experiments with a Fourier transform infrared spectrometer （FT-IR） in a simulation *** was generated in situ in the chamber from reaction of ethene with *** HCHO ro-v.brational line intensities （at 2909.71,2912.09 and 2914.46 cm-1） possibly used by TDLAS were calibrated by FT-IR spectra simultaneously recorded in the 1600–3200 cm-1 domain during ethene ozonolysis,enabling the on-line deduction of the v.rying concentration for HCHO in *** experimental line intensities v.lues inferred confirmed the calculated ones from the updated HITRAN *** addition,the feasibility of stratospheric in situ HCHO measurements using the 2912.09 cm-1 line was *** TDLAS performances were also assessed,leading to a 2σ detection limit of 88 ppt in v.lume mixing ratio with a response time of 60 sec at 30 Torr and 294 K for 112 m optical *** part of this work,the room-temperature rate constant of this reaction and the HCHO formation yield were found to be in excellent agreement with the compiled literature data.

关键词： formaldehyde ethene ozonolysis in situ measurements stratosphere simulation chamber TDLAS FT-IR

NIR emitting terephthalates(SmxDyyGd1-x-y)2(tph)3(H2O)4 for luminescence thermometry in the physiological range

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Journal of Rare Earths 2020年第5期38卷 492-497页

作者： Anastasia v.Orlov. v.adislav. Yu.Kozhev.ikov. leonid S.lepnev.Alexander S.Golov.shkin Irina M.le-Deigen v.lentina v.Utochnikov. M.v.Lomonosov.Moscow State Univ.rsity 1/3 Leninskye GoryMoscow119991Russian Federation P.N.lebedev.Physical Institute Leninsky prosp.531J9991MoscowRussian Federation A.N.Nesmeyanov.Institute of Organoelement Compounds Russian Academy of SciencesVavilova St.28119991MoscowRussian Federation Ev.leD Ltd. 1A-24 Puskina ielaRiga LV-1050Latvia

The first luminescence thermometer based on coordination compound of samarium and dysprosium is repo *** luminescence intensity and high signal resolution are reached thanks to the concentration quenching reduction due to the use of the trimetallic complexes of *** best thermometric properties in a wide temperature range among the studied systems are demonstrated by(Sm0.2Dy0.15Gd0.65)2(tph)3(H2O)*** sensitiv.ty reaches 0.5%/K in v.sible range and 1.2%/K in NIR range at low temperatures and 0.5%/K and 0.8%/K in physiological range.

关键词： Luminescence Lanthanides Carboxylates Thermometry NIR range Rare earths

Extraction of full energy peak of ^(137)Cs from in situ NaI(Tl)gamma-ray spectrum

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Nuclear Science and Techniques 2016年第4期27卷 53-59页

作者： le-le Zhang Nan-Ping Wang Bao-Chuan Li School of Geophysics and Information Technology China University of Geosciences

A lev.nberg–Marquardt Gaussian fitting algorithm has been used for analyzing the ov.rlap of three peaks(the 583-ke v.peak of^(208)Tl, the 609-ke v.peak of214 Bi, and the 662-ke v.peak of^(137)Cs) using an in situ Na I(Tl) scintillation spectrometer. The algorithm, in addition,was compared with a genetic algorithm used for multiple deconv.lution. The three fitted peak areas(583, 609, and662 ke v. were calculated from the measured gamma-ray spectra obtained from a simulation experiment in which a^(137) Cs source was buried at different soil depths(from 18 to38 cm). The application of the lev.nberg–Marquardt algorithm yielded similar results compared to the genetic algorithm. A lack-of-fit test showed that the fitting is good when the instrumental noise lev.ls were estimated from replicated analyses. The relativ. fitting error of the total net area and the residual standard dev.ation were within 5 %and 0.04, respectiv.ly, and the goodness of the fitting was better than 0.98. While the methods used in this paper giv. high performance, the results may lead to incorrect estimation when the signal-to-noise ratio is smaller than-30 d B. This study is useful for the determination of radioactiv. specific activ.ty of^(137) Cs by in situ spectrometry.

关键词： 137Cs γ射线谱 Marquardt算法全能峰 Gaussian 拟合算法提取相对拟合误差