检索结果-南通市图书馆

Novel Superconducting Electrides in Ca–S System under High Pressures

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2021年第3期38卷 69-74页

作者： Yun-Xian Liu Chao Wang Shuai Han Xin Chen Hai-Rui Sun Xiao-Bing Liu Laboratory of High Pressure Physics and Material Science(HPPMS) School of Physics and Physical EngineeringQufu Normal UniversityQufu 273165China

Due to their unique structure properties,most of the electrides that possess extra electrons locating in interstitial regions as anions are *** and superconducting electrides are very rare under ambient *** systematically search possible compounds in Ca-S systems stabilized under various pressures up to 200 GPa,and investigate their crystal structures and properties using first-principles *** predict a series of novel stoichiometries in Ca-S systems as potential superconductors,including P2_(1)/m Ca_(3)S, Pnma Ca_(3)S,Pnma Ca_(2)S,Cmcm Ca_(2)S,Fddd CaS_(2),Immm CaS_(3) and C2/c CaS_(4).The P4mbm Ca_(3)S phase exhibits a maximum Tc value of ~*** is interesting to notice that the P2_(1)/m Ca_(3)S and Pnma Ca_(2)S stabilized at 60 and 50 GPa behave as superconducting electrides with critical temperatures Tc of 7.04 K and 0.26 K,*** importantly,our results demonstrate that P2_(1)/m Ca_(3)S and Pnma Ca_(2)S are dynamically stable at 5 GPa and 0 GPa,respectively,indicating a high possibility to be quenched to ambient condition or synthesized using the large volume press.

关键词： ambient stabilized locating

An All-Polarization-Maintaining Multi-Branch Optical Frequency Comb for Highly Sensitive Cavity Ring-Down Spectroscopy

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2020年第6期37卷 26-30页

作者： Kai Ning Lei Hou Song-Tao Fan Lu-Lu Yan Yan-Yan Zhang Bing-Jie Rao Xiao-Fei Zhang Shou-Gang Zhang Hai-Feng Jiang Key Laboratory of Time and Frequency Primary Standards National Time Service CenterChinese Academy of SciencesXi’an 710600China School of Astronomy and Space Sciences University of Chinese Academy of SciencesXi’an 710069China Institute of Photonics and Photon-Technology Northwest UniversityXi’an 710069China

We demonstrate a multi-branch all polarization-maintaining Er:fiber frequency comb with five application ports for precise measurement of atomic/molecular transition frequencies in the near-infrared region.A fully stabilized Er:fiber frequency comb with a nonlinear amplifying loop mirror is *** in-loop relative instability of stabilized carrier-envelope-offset frequency is 5.6×10-18 at 1 s integration time,while that of the repetition rate is well below 1.8×10-12 limited by the measurement noise floor of the commercial frequency *** application ports are individually optimized for applications with different wavelengths(1064 nm,1083 nm,1380 nm,1637 nm and 1750 nm).The beat note between the optical frequency comb and continuous laser exhibits the signal-to-noise ratio of at least 30 dB at a resolution bandwidth of 100 *** in-loop frequency instability of the comb is evaluated to be good enough for measurement of rotation-resolved transitions of molecules below 1 kHz resolution.

关键词： stabilized Polarization Highly

Channeling Alignment for Epitaxial Light-Mass Film on Heavy-Mass Substrate

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 1994年第5期11卷 293-296页

作者： YIN Shiduan XIAO Guangming ZHU Peiran Institute of Semiconductors Academia SinicaBeijing 100083 Institute of Physics Academia SinicaBeijing 100080

A simple procedure for obtaining a background-free backscattering spectrum of a light-mass film on a heavy-mass substrate by a normal incidence/grazing exit geometry has been *** this method such films can be aligned rapidly and accurately,and the impurity or defect information on the films can be obtained without need for *** is given from MeV^(3)Li^(+)analysis of a deposited film of Si on a single crystal substrate of yttria-stabilized,cubic zirconia.

关键词： film cubic stabilized

Preparation of electrolyte membranes for micro tubular solid oxide fuel cells

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2008年第9期51卷 808-812页

作者： TAN XiaoYao YIN WeiNing MENG Bo MENG XiuXia YANG NaiTao MA ZiFeng School of Chemical Engineering Shandong University of TechnologyZibo 255049China Department of Chemical Engineering Shanghai Jiaotong UniversityShanghai 200240China

Yttria-stabilized zirconia (YSZ) micro tubular electrolyte membranes for solid oxide fuel cells (SOFCs) were prepared via the combined wet phase inversion and sintering technique. The as-derived YSZ mi- cro tubes consist of a thin dense skin layer and a thick porous layer that can serve as the electrode of fuel cells. The dense and the porous electrolyte layers have the thickness of 3-5 μm and 70-90 μm, respectively, while the inner surface porosity of the porous layer is higher than 28.1%. The two layers are perfectly integrated together to preclude the crack or flake of electrolyte film from the electrode. The presented method possesses distinct advantages such as technological simplicity, low cost and high reliability, and thus provides a new route for the preparation of micro tubular SOFCs.

关键词： solid oxide fuel cell micro tube yttrium stabilized zirconia (YSZ) phase inversion

Finite element method based on combination of "saddle point" variational formulations

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 1997年第3期40卷 285-300页

作者：周天孝 Aeronautical Computing Technology Research Institute Xi'an 710068 China

A modified mixed/hybrid finite element method, which is no longer required to satisfy the Babuska-Brezzi condition, is referred to as a stabilized method Based on the duality of vanational principles in solid mechanics, a new type of stabilized method, called the combinatorially stabilized mixed/hybrid finite element method, is presented by weight-averaging both the primal and the dual "saddle-point" schemes. Through a general analysis of stability and convergence under an abstract framework, it is shown that for the methods only an inf-sup inequality much weaker than Babuska-Brezzi condition needs to be satisfied. As a concrete application, it is concluded that the combinatorially stabilized Raviart and Thomas mixed methods permit the C -elements to replace the H(div; Ω)-elements.

关键词： mixed/hybrid finite element stabilized method error estimates saddle point problem.

A Study on the Far Wake of Elliptic Cylinders

在线全文

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2017年第1期113卷 35-55页

作者： Subhankar Sen Sanjay Mittal Department of Mechanical Engineering Indian Institute of Technology KanpurIndia Department of Aerospace Engineering Indian Institute of Technology KanpurIndia

The evolution of far wake of stationary elliptic cylinders with angle of attack is investigated for the unsteady flow at Re=200 using a stabilized finite-element *** Reynolds number,Re,is based on the major axis of cylinder and free-stream *** aspect ratios,AR considered are 0.2,0.5 and 0.8 while the angle of attack,αvaries from 0° to 90°.With increasingα,the Karman or primary shedding frequency of each cylinder decreases monotonically while the primary wavelength and time-averaged as well as *** increase *** time-averaged lift and moment coefficients initially increase withαand then *** power spectrum analysis of unsteady transverse velocity signal at various stations along the wake centerline is used to study the associated *** Karman or primary shedding frequency exists for eachα.For the AR=0.2 cylinder,the secondary and subsequently,low magnitude tertiary frequencies appear in the wake asαcontinues to increase from 30°.In contrast to the decaying nature of primary frequency withα,secondary frequency exhibits a nonmonotonic *** secondary frequency in general is not a sub-harmonic of the *** suggests that the secondary structures do not form due to merging of primary *** increasingα,the location of formation of secondary structures advances *** a given orientation,the upstream advancement is more dominant with decreasing *** spectrum analysis indicates that the wake state for confined flow is characterized by the primary frequency alone,*** imposition of blockage suppresses the formation of secondary structures.

关键词： Elliptic cylinder stabilized finite-element far wake angle of attack blockage

SYNTHESIS AND LIGHTFASTNESS PROPERTIES OF DYES CONTAINING HINDERED PIPERIDINE RESIDUES AS INTERNAL STABILIZING GROUPS

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of China Textile University(English Edition) 1991年第4期9卷 24-33页

作者：戴瑾瑾 John Griffiths Department of Textile Chemical Engineering CTU Department of Colour Chemistry Univ.of LeedsU.K.

The representative azo and anthraquinone dyes containing an insulated hindered piperidinegroup were *** effect of these pendent groups on lightfastness properties of the dyeswas studied,both in ethyl acetate solution and on cellulose acetate and polyester *** differ-ent trend of fading rates of azo dyes and anthraquinone dyes in solution and on substrates suggestsdifferent fading mechanisms operating in each case.

关键词： lightfastness synthesis dyes hindered piperidine group intra-molecular stabilized dye

TOTAL SYNTHESIS OF SARCOPHINE

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1992年第1期37卷 86-87页

作者：郑其煌苏镜娱曾陇梅 Department of Chemistry Zhongshan University Guangzhou 510275 PRC

Sarcophine 1 is one of cembranolides, most of which have cytotoxicity and antitumour activity. 1 is an effective chemical protector owing to its toxicity. We now report the synthesis of sarcophine 1. The important intermediate 3, 7-dimethyl-6, 7-epoxy-8-thiophenyl-2-octenal 2 and 6-methyl-8-trimethylsiloxy-oct-6-ene-2-one-1-acid acetate 3, i. e. fragment C1—C8 and C9—

关键词： acetate epoxy cytotoxicity hexane stabilized lactone starting sulfur EtOH

PHASE-LOCKING OF HIGH POWER GYROTRON OSCILLATOR

在线全文

学校读者我要写书评

暂无评论

Journal of Electronics(China) 1996年第1期13卷 89-96页

作者： Tang Changjian (Department of Applied Physics, Chengdu University of Science & Technology of China, Chengdu 610065)Yang Zhonghai Liu Pukun(Institute of High Energy Electronics, University of Electronic Science & Technology of China, Chengdu 610054) Department of Applied Physics Chengdu University of Science & Technology of China Chengdu Institute of High Energy Electronics University of Electronic Science & Technology of China Chengdu

The phase-locking process is studied for high-power gyrotron oscillator driven by an external signal. The phase-locking nonlinear differential equations are derived, and the condition of phase-locking is shown and analyzed. The phase-locking signal can be introduced after gyrotron oscillates into saturation or before it. Two different ways of inputting signal make markable influence on the phase-locking process, this phenomenon is discussed. In this paper, the numerical calculations and analysis are given for gyrotron TE13 mode.

关键词： Microwave oscillator Gyrotron Self-consistent nonlinear theory Phase-locking stabilized frequency