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Superconductivity modulated by Binary Doping in Nd1-xBaxFeAsO1-2xF2x

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Journal of modern Physics 2011年第6期2卷 463-471页

作者： C. Q. Qu Z. y Liu y. m Lu C. Z Chen C. B Cai A. H Fang F. Q Huang m. F Wang X. m Xie 不详

Binary doping effect is studied for the Fe-based superconductors of Nd1-xBaxFeAsO1-2xF2x(x = 0.02, 0.05, 0.1, 0.15, 0.2). The X-ray diffractions show that the c-axis lattice constant decreases monotonously with the doping content, in contrast to the little change in the a-axis. Temperature dependences of electric resistivity and magnetic susceptibility reveal that the superconductivity for the studied system emerges at x = 0.1, and enhances together with Hc2(0) as the doping content x increases further. In case of x = 0.2, the superconducting critical temperature reaches as high as 50 K, which is the first demonstration of superconductivity with a high fluorine-doping induced by both electron and hole doping in this family. Negative Hall coefficient (RH) indicates that electron-type carriers are dominated in the present samples. The complicated temperature dependence of RH, is believed to arise from a multiband effect together with a complicated scattering, especially at the tem-perature near the TC.

关键词： Binary Doping Iron-Based Superconductor Flux Pinning Scattering

Enhancing Heat Transfer and Energy Storage Performance of Shell-and-Tube Latent Heat Thermal Energy Storage Unit with Unequal-Length Fins

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Journal of Thermal Science 2023年第6期32卷 2018-2031页

作者： WU yangyang LI Dong yANG Ruitong mÜSLÜm Arıcı LIU Changyu School of Architecture and Civil Engineering Northeast Petroleum UniversityDaqing163318China Engineering Faculty Mechanical Engineering DepartmentKocaeli UniversityUmuttepe CampusKocaeliİzmit41001Turkey

Previous studies in literatures adequately emphasized that inserting fins into phase change material is among the most promising techniques to augment thermal performance of shell-and-tube latent heat thermal energy storage *** this study,the novel unequal-length fins are designed from the perspective of synergistic benefits of heat transfer and energy storage performance,and the effects of arrangement,number and total length of unequal-length fins are numerically *** show that utilization of fins with ascending length,when short and long fins are located in the inlet and outlet of heat transfer fluid respectively,can further promote the heat transfer and energy storage performance compared with equal length fins,and a maximum 6.17%and 0.43%increment of heat transfer performance and stored energy is achieved in full melting time,*** number of unequal-length fins plays a major role in the energy storage,and 18.95%and 0.91%improvement of heat transfer performance and stored energy is realized when equipped with 2 unequal-length fins.A 21.17%improvement of the heat transfer performance is obtained when the total length of unequal-length fins is 18 *** present study is helpful to make further efforts to enhance heat transfer and energy storage of shell-and-tube latent heat thermal energy storage unit with unequal-length fins.

关键词： unequal-length fin enhanced heat transfer energy storage shell and tube heat exchanger PCm

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金属板材成形中拉深损伤模拟的两种求解方法

塑性工程学报 2002年第4期9卷 47-55页

作者：郭英乔 y.m.Li K.Saanouni A.Cherouat G.Loppin K.Debray Lab.GmmS UniversityofReimsChampagneArdenne GSm/LASmIS

讨论用数值模拟预测板材成形中发生拉深损伤破坏的两种不同的求解方法。第一种是采用完全耦合的弹塑性破坯模型的动力显式数值方法。基于状态参量的不可逆热力学过程 ,完全耦合的本构方程考虑各向同性强化和拉深。这些已引入有限元软件A... 详细信息

讨论用数值模拟预测板材成形中发生拉深损伤破坏的两种不同的求解方法。第一种是采用完全耦合的弹塑性破坯模型的动力显式数值方法。基于状态参量的不可逆热力学过程 ,完全耦合的本构方程考虑各向同性强化和拉深。这些已引入有限元软件ABAQUS/E用于对金属成形的模拟。在数值技术方面 ,隐式积分方法被用来对本构方程的局部时间积分 ,动力显式技术用于求解总体平衡方程。第二种方案是采用简化的损伤模型的方法 ,被称为逆法 (InveseApprch)。I.A被限定在考虑各向同性强化和损伤的塑性全量理论基础上的简单的本构关系。做比例加载和临界损伤达到以后的损伤饱和假定 ,可以得到损伤演化方程的封闭解。这两种损伤模型在编程中的实施采用两种方式 :计算中考虑或不考虑损伤作用 ,也就是耦合的或非耦合的计算。

关键词：板材成形深拉深损伤模型数值模拟

Locally advanced pancreatic cancer: staging, operability, and the importance of multimodality therapy

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Hepatobiliary Surgery and Nutrition 2020年第4期9卷 497-500页

作者： Rebecca y.Kim Douglas B.Evans Kathleen K.Christians Department of Surgery and the LaBahn Pancreatic Cancer Program Medical College of WisconsinMilwaukeeWIUSA

The role for surgery in the management of locally advanced pancreatic cancer(LAPC)is nicely discussed in the manuscript by Gemenetzis et *** in the Annals of Surgery(1).As the authors acknowledge,therapeutic selection... 详细信息

关键词： Surgery cancer al.

A model for the chain-to-plane charge transfer in yBa2Cu3O6+x

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Chinese Physics B 2012年第11期21卷 450-454页

作者： V.m.matic N.Dj.Lazarov m.milic Laboratory of Theoretical Physics Institute of Nuclear Sciences “Vinca”Belgrade University

A model for the chain-to-plane charge transfer is proposed to account for the two plateaus,at 60 K and at 90 K,of the Tc(x) characteristics of the yBa2Cu3O6+x high-Tc *** is assumed that the number of holes transferred from a CuO chain of length l to two nearby CuO2 sheets is proportional to l(that is,to the number of oxygen atoms in the chain),if the chain length is greater than,or equal to,a certain critical chain length,lcr,that is required to trigger the charge transfer *** holes are assumed to have been transferred from chains of length l更多还原AbstractFilter('ChDivSummary', 'ChDivSummarymore', 'ChDivSummaryReset');

关键词： yBCO oxygen ordering critical temperature doping

Perfect Single Qubit mirroring Effects on Two and Three maximally Entangled Qubits

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Communications in Theoretical Physics 2013年第1期59卷 7-10页

作者： m.Avila Centro Universitario UAEm Valle de Chalco UAEMex Mar' a IsabelValle de ChalcoEstado de M'exicoCP 56615Mexico

Perfect quantum state mirroring in a chain of N spins is defined as the condition in which the state 丨i 丨of the chain is swapped into the state 丨N - i丨 within a time evolution interval r. Such a phenomenon is an interesting way of transfering entanglement. An expressions for the perfect mirroring of a single qubit contained in a spin chain were proposed in the past. We exploit such an expressions for calculating the evolution times in chains of both two and three spins. In the case of a chain of two qubits, we derive conditions under which the associated four Bell states diagonalize the Hamiltonian. It is found that for the two Bell states 丨Ф＋） and 丨Ф-）, perfect mirroring does not occur （i.e. entanglement is not preserved under swapping）. On the other hand, perfect single qubit mirror effect （entanglement preservation） indeed occurs for the other two Bell states 丨ψ＋） and 丨ψ-） which are mapped into 丨Ф＋） and 丨Ф-） respectively. For the case of a chain of three qubits, the effects of a perfect single qubit mirroring on a set of four maximally entangled three qubit states ψl, ψ2, X1, and X2are studied. Due to the fact that quantum mirroring preserves maximal entanglement, the states ψ1 and ψ2 are not altered. However, quantum mirroring changes the states X1 and X2 only if we apply perfect quantum state mirroring in the site a = 1 of the three qubits spin chain. The above constrains the preservation of maximal entanglement under qubit mirroring of such a state. Due to the fact that swapping has already been experimentally tested, a posible, experimental implementations of single qubit mirroring is possible.

关键词： time evolution of a state perfect quantum state mirroring of a single qubit Bell states Gisinstates quantum mirroring of Bell states quantum mirroring of Gisin states entanglement preset-vation

TREATmENT OF mETALS, POLymER FILmS, AND FABRICS WITHA ONE ATmOSPHERE UNIFORm GLOW DISCHARGE PLASmA(OAUGDP) FOR INCREASED SURFACE ENERGy AND DIRECTIONAL ETCHING

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Acta metallurgica Sinica(English Letters) 2001年第6期14卷 391-407页

作者： J. Reece Roth and Z. y Chen (Plasma Sciences Laboratory, Department of Electrical and Computer Engineering, University of Tennessee, Knoxville, TN 37996-2100, USA) Peter P.- y Tsai (Textiles and Nonwovens Development Center (TANDEC), University of Tenness Plasma Sciences Laboratory Department of Electrical and Computer Engineering University of Tennessee Textiles and Nonwovens Development Center (TANDEC) University of Tennessee

Direct exposure of samples to the active species of air generated by a One Atmosphere Uniform Glow Discharge Plasma (OAUGDP) has been used to etch and to increase the surface energy of metallic surfaces, photoresist, polymer films, and nonwoven fab- rics. The OAUGDP is a non-thermal plasma with the classical characteristics of a DC normal glow discharge that operates in air (and other gases) at atmospheric pres- sure. Neither a vacuum system nor batch processing is necessary. A wide range of applications to metals, photoresist, films, fabrics, and polymeric webs can be accom- modated by direct exposure of the workpiece to the plasma in parallel-plate reactors. This technolopy is simple, it produces effects that can be obtained in no other way at one atmosphere; it generates minimal pollutants or unwanted by-products; and it is suitable for individual sample or online treatment of metallic surfaces, wafers, films, and fabrics. Early exposures of solid materials to the OAUGDP required minutes to produce rela- tively small increases of surface energy. These durations appeared too long for com- mercial application to fast-moving webs. Recent improvements in OAUGDP gas com- position, power density, plasma quality, recireulating gas flow, and impedance match- ing of the power supply to the parallel plate plasma reactor have made it possible to raise the surface energy of a variety of polymeric webs (PP, PET PE etc.) to levels of 60 to 70 dynes/cm with one second of exposure. In air plasmas, the high surface ener- gies are not durable, and fall to 50 dynes/cm after periods of weeks to months. Here, we report the exposure of metallic surfaces, photoresist, polymeric films, and nonwo- ven fabrics made of PP and PET to an impedance matched parallel plate OAUGDP for durations ranging from one second to several tens of seconds. Data will be re- ported on the surface energy, wettability, wickability, and aging effect of polymeric films and fabrics as functions of time of exposur

关键词： atmosphere glow discharge plasma surface energy etching of material surface

Insurance coverage for male infertility care in the United States

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Asian Journal of Andrology 2016年第3期18卷 339-341,I0006页

作者： James m Dupree Department of Urology Divisions of Andrology and Health Services Research and Department of Obstetrics and Gynecology University of Michigan 1500 E Medical Center Drive 3875 Taubman Center SPC 5330 Ann Arbor M148109-5330 USA.

Infertility is a common condition experienced by many men and women, and treatments are expensive. The World Health Organization and American Society of Reproductive medicine define infertility as a disease, yet private companies infrequently offer insurance coverage for infertility treatments. This is despite the clear role that healthcare insurance plays in ensuring access to care and minimizing the financial burden of expensive services. In this review, we assess the current knowledge of how male infertility care is covered by insurance in the United States. We begin with an appraisal of the costs of male infertility care, then examine the state insurance laws relevant to male infertility, and close with a discussion of why insurance coverage for male infertility is important to both men and women. Importantly, we found that despite infertility being classified as a disease and males contributing to almost half of all infertility cases, coverage for male infertility is often excluded from health insurance laws. Excluding coverage for male infertility places an undue burden on their female partners. In addition, excluding care for male infertility risks missing opportunities to diagnose important health conditions and identify reversible or irreversible causes of male infertility. Policymakers should consider providing equal coverage for male and female infertility care in future health insurance laws.

关键词： health policy insurance male infertility public policy

THERmODyNAmIC CRITERION OF SPINODAL DECOmPOSITION IN TERNARy SySTEmS

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Acta metallurgica Sinica(English Letters) 1991年第8期4卷 75-81页

作者： JIANG Bohong ZHANG meihua WEI Qing XU Zuyao(T.y.Hsu) Shanghai Jiaotong University,Shanghai,China Shanghai Jiaotong Univ Shanghai China

By expanding the Gibbs free energy of a ternary system into a Taylor series with respect to the composition,a thermodynamic criterion of spinodal decomposition is conducted as G_(xx)(δx)2+2G_(xx)δxδy+G_(yy)(δy)~2m which,various conditions of spinodal decomposition are *** G_(xx)y)~2-G_(xx)G_(yy)mposition unrestricted by the direction of composition fluctuation;when G_(xx)y)~2-G_(xx)G_(yy)>0,or G_(xx)>0, G_(xy)~2-G_(xx)G_(yy)>0,as well as G_(xx)=0,are all considered as unstable decomposition restricted by the direction of composition fluctuation δx and δ*** phenomenon of turning round in composition during spinodal decomposition is attempted to be explained from above point of *** computer calculated ranges of unstable decomposition according to the criterion of spinodal decomposition on Cu-Ni-Fe ternary system is consistent with the experimental re- sults obtained from literatures.

关键词： spinodal decomposition thermodyamic criterion Cu-Ni-Fe