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工程热物理学报 2006年第1期27卷 1-4页

作者：罗二仓戴巍 radebaugh ray 中国科学院理化技术研究所北京100080 美国国家标准技术研究所科罗拉多80305

本文从解析的角度论证了交变流动回热器不仅具有经典热力学理论所认为的回热功能,而且具有热声理论所论述的热声功能,并指出交变流动斯特林热机进行的不是传统热力分析认为的两个等温过程和两个等容回热过程组成的斯特林循环。

关键词：交变流动回热器热声功能回热功能

可用于THz探测器的百赫兹高频脉管制冷性能

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稀有金属材料与工程 2008年第A4期37卷 266-270页

作者：甘智华邱利民 Michael Lewis Srinivas Vanapalli ray radebaugh 浙江大学浙江杭州310027 National Institute of Standards and Technology BoulderCO80305 USA MESA+ Institute of Nanotechnology University of Twente7500 AE EnschedeNetherlands

THz探测技术的发展对低温制冷技术提出了更为紧凑高效的需求,为了进一步减小低温制冷机的体积,提高制冷机运行频率是一个重要的方法。近期的研究表明,如果配合制冷机频率的提高,增加相应的充气压力,缩小制冷机的体积等可以使制冷机工作... 详细信息

THz探测技术的发展对低温制冷技术提出了更为紧凑高效的需求,为了进一步减小低温制冷机的体积,提高制冷机运行频率是一个重要的方法。近期的研究表明,如果配合制冷机频率的提高,增加相应的充气压力,缩小制冷机的体积等可以使制冷机工作在百赫兹、甚至千赫兹的水平上,为低温制冷机走向微型化提供了参考。本文给出了世界上首例采用线性压缩机驱动的、运行在百赫兹以上频率,并在80K有2W制冷量的高效脉管制冷机,其无负荷制冷温度为50K,并且该制冷机具有快速降温的特点,从环境温度冷却到80K的时间为7min,达到50K仅需要11min。

关键词：脉管制冷高频回热器 THz应用

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美国小型制冷机的发展

低温与特气 1989年第4期 1-7页

作者： ray radebaugh 杨志宏美国国家标准技术研究所浙江大学

在近几年里,美国各种小型制冷机都取得了巨大的进展。本文介绍了布雷顿、焦耳—汤姆逊、斯特林、脉冲管和磁制冷器的进展情况。工作可靠性要求已成为新的研究领域的主要推动力。评论了最近几年在改进制冷机可靠性方面采取的各种方法,对... 详细信息

在近几年里,美国各种小型制冷机都取得了巨大的进展。本文介绍了布雷顿、焦耳—汤姆逊、斯特林、脉冲管和磁制冷器的进展情况。工作可靠性要求已成为新的研究领域的主要推动力。评论了最近几年在改进制冷机可靠性方面采取的各种方法,对不同工作循环制冷机的利弊作了比较,并对每种制冷机的最新改进进行了讨论。

关键词：制冷机斯特林制冷功率冰机制冷装置制冷器回热器美国美利坚合众国北美洲

1985年以来低温制冷机的研制和应用(节译)

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电子科学技术评论 2005年第4期 60-61,24页

作者： ray radebaugh 王和军美国国家标准技术研究所中国电子科技集团公司第16研究所合肥230061

大约从1985年开始,低温制冷机取得许多重大的新进展,使制冷机在效率、寿命、紧凑性和最低极限温度方面均有较大的突破。如电力能源的高温超导体,卫星用红外探测器、核磁共振成像(MRI)系统的超导磁体冷却,低温外科手术,以及医学、工业和... 详细信息

大约从1985年开始,低温制冷机取得许多重大的新进展,使制冷机在效率、寿命、紧凑性和最低极限温度方面均有较大的突破。如电力能源的高温超导体,卫星用红外探测器、核磁共振成像(MRI)系统的超导磁体冷却,低温外科手术,以及医学、工业和空间应用的小型气体液化。本文揭示各种类型低温制冷机的新的进展,如何提高制冷机的性能来满足一些新的应用。

关键词：低温制冷机空间应用标准技术研究所美国核磁共振成像高温超导体红外探测器极限温度

Numerical simulation of square shaped particle sedimentation

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Particuology 2024年第1期84卷 107-116页

作者： Govind Sharma Bahni ray Department of Mechanical Engineering Indian Institute of Technology DelhiHauz KhasNew Delhi110016India

Direct numerical simulations of square particle sedimentation in a viscous incompressible fluid are presented to examine the effects of sharp edges for various particle-to-fluid density ratios and different initial inclination *** settling process exhibits four different motion regimes;non-oscillatory,non-uniform centered oscillatory,uniform off-centered oscillatory,and non-uniform off-centered(irregular)*** moderate density ratios,we observe that the rotational motion of settling square particle varies with the initial inclination *** employ Dynamic Time Warping and Fast Fourier Transform to analyze translational and angular *** systems are described using phase-space plots,and a chaotic phenomenon is observed at a higher density ratio.

关键词： Sedimentation Distributed Lagrangian multiplier Phase synchronization Oscillations

TALYS calculation and a short review of the experimental status of proton capture studies on p-nuclei:A guide to future investigation

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Chinese Physics C 2024年第6期48卷 102-111页

作者： Indrani ray Argha Deb Physics Department Jadavpur UniversityKolkata-700032India

TALYS calculations were performed to obtain the theoretical proton capture cross-sections on the p-nuclei.A short review on the status of related experimental studies was also *** basic properties such as Q-values,Coulomb barrier,Gamow peak,Gamow Window,and decay properties of the parent and daughter nuclei were *** experimental parameters,e.g.,beam energy,beam current,targets,and detectors,used in experimental investigations reported in the literature,were *** results of the TALYS calculations in the Gamow region were compared with the corresponding experimental values wherever *** study is expected to facilitate the planning of future experiments.

关键词： p-nuclei proton capture cross-section gamma ray Gamow energy TALYS TENDL KADoNis

Functional cure of chronic hepatitis B-hope or hype?

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World Journal of Hepatology 2024年第9期16卷 1199-1205页

作者： Gautam ray Gastroenterology Unit Department of MedicineB.R.Singh HospitalKolkata 700014West BengalIndia

Chronic hepatitis B constitutes a substantial disease burden *** steps advocated by the World Health Organization in 2016 to eradicate hepatitis B by 2030 has failed to achieve significant progress,especially with respect to immu-nization coverage and linkage to *** lack of governmental and public awar-eness regarding the long-term implications of hepatitis B burden cause under-funding of developmental *** presently approved treatment modalities have limited efficacy in complete viral eradication,hence the need for newer molecules to achieve functional cure(sustained undetectable hepatitis B surface antigen(HBsAg)and hepatitis B virus DNA in peripheral blood after a finite period of therapy).However,preliminary results from trials of novel therapies show their inadequacy to achieve this end by themselves but better performance with a low baseline serum HBsAg with nucleos(t)ide analogues(NA)treatment which need to be combined with/without pegylated interferon as an *** therapy is limited by cost and adverse events and need to show incremental benefit over the standard of care(long-term NA therapy)with respect to efficacy and drug toxicities,making the development process ***,while such therapies continue to be tested,strategies should still focus on prevention of transmission by non-pharmaceutical measures,vaccination and increasing linkage to care.

关键词： Hepatitis B Drugs Clinical trial Therapy Novel therapies Functional cure

A new method for deriving broad-band polar motion geodetic excitations

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Geodesy and Geodynamics 2024年第5期15卷 453-464页

作者： Wei Chen Jiesi Luo Jim ray Jiancheng Li Hubei Luojia Laboratory School of Geodesy and GeomaticsWuhan UniversityWuhan 430079China National Oceanic and Atmospheric Administration Silver SpringMDUSA Central South University Changsha 410083China

While the geodetic excitationχ(t)of polar motion p(t)is essential to improve our understanding of global mass redistributions and relative motions with respect to the terrestrial frame,the widely adopted method to deriveχ(t)from p(t)has biases in both amplitude and phase *** study has developed a new simple but more accurate method based on the combination of the frequency-and time-domain Liouville's equation(FTLE).The FTLE method has been validated not only with 6-h sampled synthetic excitation series but also with daily and 6-h sampled polar motion measurements as well asχ(t)produced by the interactive webpage tool of the International Earth Rotation and Reference Systems Service(IERS).Numerical comparisons demonstrate thatχ(t)derived from the FTLE method has superior performances in both the time and frequency domains with respect to that obtained from the widely adopted method or the IERS webpage tool,provided that the input p(t)series has a length around or more than 25 years,which presents no practical limitations since the necessary polar motion data are readily *** FTLE code is provided in the form of Mat Lab function.

关键词： Earth rotation Polar motion Geodetic excitation Liouville's equation Mat Lab

Painlevéintegrability,auto-Bäcklund transformations,new abundant analytic solutions including multi-soliton solutions for time-dependent extended KdV8 equation in nonlinear physics

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Journal of Ocean Engineering and Science 2024年第5期9卷 489-507页

作者： Shailendra Singh S.Saha ray National Institute of Technology Department of MathematicsRourkela 769008India

In this paper,a new eighth-order(1+1)-dimensional time-dependent extended KdV equation has been *** considered equation is being found completely integrable by using the Painlevéanalysis ***,three auto-Bäcklund transformations have been generated by truncating the Painlevéseries at a constant *** auto-Bäcklund transformations have been used to derive various analytic solution families for the newly developed *** solutions include the kink-antikink soliton,kink-soliton,antikink-soliton,periodic-soliton,complex kink-soliton and complex periodic-soliton ***-soliton solutions including N-soliton solution,have been obtained by using the simplified Hirota’s method for the considered *** the results are being expressed graphically to signify the physical importance of the considered equation.

关键词： Higher-order KdV equation Painlevéanalysis Auto-Bäcklund transformation Simplified Hirota method

Population Dynamics in an Advective Environment

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Communications on Applied Mathematics and Computation 2024年第1期6卷 399-430页

作者： King-Yeung Lam ray Lee Yuan Lou Department of Mathematics The Ohio State UniversityColumbusOH43210USA School of Mathematical Sciences CMA-Shanghai and MOE-LSCShanghai Jiao Tong UniversityShanghai200240China

We consider a one-dimensional reaction-diffusion equation describing single-and two-species population dynamics in an advective environment,based on the modeling frameworks proposed by Lutscher et *** *** analyze the effect of rate of loss of individuals at both the upstream and downstream *** the single-species case,we prove the existence of the critical domain size and provide explicit formulas in terms of model *** further derive qualitative properties of the critical domain size and show that,in some cases,the critical domain size is either strictly decreasing over all diffusion rates,or monotonically increasing after first decreasing to a *** also consider competition between species differing only in their diffusion *** two species having large diffusion rates,we give a sufficient condition to determine whether the faster or slower diffuser wins the *** also briefly discuss applications of these results to competition in species whose spatial niche is affected by shifting isotherms caused by climate change.

关键词： Reaction-diffusion-advection Critical domain size Competition Climate change