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Nuclear Science and Techniques 2016年第3期27卷 153-158页

作者： Xiu-fang Li De-Qing fang Yu-Gang Ma Shanghai Institute of Applied Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

The effective neutron and proton root-meansquare radius of stable and unstable nuclei(^(12-15,17)B,^(12-20)C,^(14-21)N,^(16-24)O and ^(18-21,23-26)F) were deduced from the charge-changing cross section,σ_(cc),and the interaction cross sections,σ_I,by using a statistical abrasion-ablation model *** extracted proton radii are in good agreement with the data from the Atomic Data and Nuclear Data Tables within the ***,we can observe that the neutron skin thickness increases monotonously with the increasing neutron number in these isotopes,which is consistent with the systematical trend of theoretical calculations.

关键词：中子皮厚度作用截面同位素变化截面电荷均方根半径测定不稳定核

Synthesis and Crystal Structure of (4S)-5-(2-Methoxy-2-oxoethylamino)-5-oxo- 4-(3,4,5-trimethoxybenz.mido) Pentanoic Acid

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Chinese Journal of Structural Chemistry 2005年第6期24卷 706-710页

作者： LIXun XUWen-fang CollegeofPharmacy ShandongUniversityJinan250012China

The crystal structure of (4S)-5-(2-methoxy-2-oxoethylamino)-5-oxo-4-(3,4,5- trimethoxybenz.mido) pentanoic acid 5 (C18H24N2O9, Mr = 412.39) has been determined by single- crystal X-ray diffraction analysis. The crystal belongs to monoclinic, space group P21/c with a = 27.665(9), b = 5.1444(16), c = 13.907(4) ?, β = 98.401(5)o, V = 1958.0(11) ?3, z.= 4, Dc = 1.399 g/cm3, μ = 0.113 mm-1, F(000) = 872, R = 0.0606 and wR = 0.1405 (I > 2σ(I)). The results con- firmed that 5 could be assigned to the tautomeric form. The intermolecular hydrogen bonds between O(5)–H(5)…O(7), N(2)–H(2)…O(6) and N(1)–H(1)…O(4) have been observed.

关键词： synthesis APN pentanoic acid crystal structure

Estimation in Discrete Reliability Growth,a Growth Model with Coefficient Condition

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Journal of Systems Science & Complexity 2016年第4期29卷 1112-1122页

作者： SHAO Xiang fang Xiangz.ong School of Mathematics Science Peking UniversityBeijing 100871China

This paper considers the well known problem of estimating reliability in discrete reliability growth context with sequence of dichotomous success-failure outcomes. More precisely, the authors generaliz. the simple order relationship constraint with some coefficients. The authors prove that under some mild conditions, the generaliz.d constraint MLE problem can be transformed to a traditional isotonic problem. The authors also study the lower confidence limit estimation of reliability with sample space ranking method. A simulation is conducted to illustrate the superiority of the proposed method.

关键词： Confidence limit discrete reliability growth isotonic regression point estimation

Development of MRPC technology for STAR-TOF

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Nuclear Science and Techniques 2005年第4期16卷 231-237页

作者： SUN Yong-Jie LI Cheng SHAO Ming CHEN Hong-fang G. EPPLEY F.GEURTS H. HUANG HUANG Sheng-Li W.J. LIOPE T. NUSSBAUM RUAN Li-Juan J. SCHAMBACH WANG Xiao-Lian WU Jian z. XU Department of Modern Physics University of Science and Technology of China Hefei 230026 China Rice University Bonner Nuclear Lab Houston TX 77005 USA University of California- Los Angeles Los Angeles CA90095 USA Brookhaven National Laboratory Upton New York 11973 USA University of Texas Austin TX 78712 USA）

A prototype of multi-gap resistive plate chamber (MRPC) modules with 6 gas gaps of 220 μm used for the time-of-flight (TOF) detectors has been developed by STAR TOF group. A tray (TOFr) composed of 28 MRPC modules was constructed and operated in STAR for the d+Au collisions and Au+Au collisions during 2003 RHIC and 2004 RHIC run. Results show its time resolution is 85 ps with the average efficiency of 95% and clear identification of K/π up to 1.6 GeV and proton/ K up to 3.0 GeV.

关键词： MRPC技术 STAR-TOF RHIC PID 气体电力探测技术

Optimiz.tion of electrocatalytic properties of NiMoCo foam electrode for water electrolysis by post-treatment processing

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Rare Metals 2015年第11期34卷 802-807页

作者： Jian-Wei Wang Yue-Fa Wang Jing-Guo z.ang Yan-Lin Yu Ge-Ge z.ou Lei Cheng Lin-Shan Wang z.z.k fang State Key Laboratory of Nonferrous Metals and Processes General Research Institute for Nonferrous Metals GRIPM Advanced Materials Co. Ltd General Research Institute for Nonferrous Metals Department of Metallurgical Engineering University of UtahSalt Lake City

Hydrogen is a potential alternative to fossil fuels in coping with the increased global energy demand,and water electrolysis is an attractive approach for H2production. Nickel–molybdenum–cobalt（Ni Mo Co） foam electrodes used for water electrolysis were prepared by the electrodeposition method, and the influence of heat treatments on the surface structure of Ni Mo Co foam electrodes,mechanical properties, and electrochemical performance of the synthesiz.d electrodes was investigated in order to optimiz. the post-treatment processes. The residual carbon in the surface of the electrode was removed by decarboniz.tion in the atmospheric condition. The carbon content decreases to lower than 200 ×10-6when the temperature exceeds 500 °C. Next, the material is reduced in hydrogen atmosphere from 500 to 1100 °C to remove the surface oxides. As the temperature increases, the surface molybdenum content increases significantly between 500 and 800 °C, the surface grains become coarser, and the tensile strength and elongation increase as well. The lowest polariz.tion overpotential is obtained at 800 °C. Below 800 °C, the electrode is only partially reduced and some black oxide z.nes are observed on the electrode surface,which leads to the higher polariz.tion overpotential. Thesamples heat-treated at the temperatures of higher than 800 °C show better strength and toughness as well as brighter appearance. However, the surface particle coarsening leads to a decrease in the specific surface area and a higher overpotential.

关键词： Water electrolysis Foam electrode Ni Mo Co Post-tr

Differentially Private Event Histogram Publication on Sequences overGraphs

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Journal of Computer Science & Technology 2017年第5期32卷 1008-1024页

作者： Ning Wang Yu Gu Jia Xu fang-fang Li Ge Yu College of Computer Science and Engineering Northeastern University Shenyang 110819 China College of Computer Electronics and Information Guangxi University Nanning 530004 China

The big data era is coming with strong and ever-growing demands on analyz.ng personal information and footprints in the cyber world. To enable such analysis without privacy leak risk, differential privacy (DP) has been quickly rising in recent years, as the first practical privacy protection model with rigorous theoretical guarantee. This paper discusses how to publish differentially private histograms on events in time series domain, with sequences of personal events over graphs with events as edges. Such individual-generated sequences commonly appear in formaliz.d industrial workflows, online game logs, and spatial-temporal trajectories. Directly publishing the statistics of sequences may compromise personal privacy. While existing DP mechanisms mainly target at normaliz.d domains with fixed and aligned dimensions, our problem raises new challenges when the sequences could follow arbitrary paths on the graph. To tackle the problem, we reformulate the problem with a three-step framework, which 1) carefully truncates the original sequences, trading off errors introduced by the truncation with those introduced by the noise added to guarantee privacy, 2) decomposes the event graph into path sub-domains based on a group of event pivots, and 3) employs a deeply optimiz.d tree-based histogram construction approach for each sub-domain to benefit with less noise addition. We present a careful analysis on our framework to support thorough optimiz.tions over each step of the framework, and verify the huge improvements of our proposals over state-of-the-art solutions.

关键词： differential privacy histogram publication sequence graph

Effect of the Electron—Phonon Coupling on Barrier D^— Quantum Dots in Magnetic Fields

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Communications in Theoretical Physics 2002年第1期37卷 99-104页

作者： XIEWen－fang DepartmentofPhysics GuangzhouUniversityGuangzhou510405China

The influence of the electron-phonon coupling on the energy of low-lying states of the barrier D- center, which consists of a positive ion located on the z.axis at a distance from the two-dimensional quantum dot plane and two electrons in the dot plane bound by the ion, is investigated at arbitrary strength of magnetic field by making use of the method of few-body physics. Discontinuous ground-state energy transitions induced by the magnetic field are reported. The dependence of the binding energy of the D- ground state on the quantum dot radius is obtained. A considerable enhancement of the binding is found for the D- ground state, which results from the confinement of electrons and electron-phonon coupling.

关键词： quantum dot electron-phonon interaction few-body physics

Estimation method for parameters of overlapping nuclear pulse signal

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Nuclear Science and Techniques 2017年第1期28卷 80-87页

作者： Hong-Quan Huang Xiao-Feng Yang Wei-Cheng Ding fang fang College of Nuclear Technology and Automation Engineering Chengdu University of Technology Fundamental Science on Radioactive Geology and Exploration Technology Laboratory East China Institute of Technology

Identification of nuclear pulse signal is of importance in radioactive measurements,especially in recogniz.ng adjacent overlapping nuclear *** this article,we propose an estimation method for parameters of typical overlapping nuclear pulse ***,the nuclear pulses are regarded as individual genes and the norm is set as the fitness ***,the global optimal solution is found by searching the population of genetic algorithm,so as to estimate the parameters of nuclear *** high precision,this method can identify parameters of overlapping nuclear pulses in the Sallen-Key Gaussian signal decomposition *** pulse recognition method is of great significance to improve the precision of radioactive measurement and is suitable for serious overlap of nuclear pluses.

关键词： Nuclear pulse Overlapping Parameter identification

On t-Dimension over Strong Mori Domains

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Acta Mathematica Sinica,English Series 2006年第1期22卷 131-138页

作者： fang Gui WANG Institute of Mathematics and Software Science Sichuan Normal University Chengdu 610068 P. R. China

In this note we prove that if R is a strong Mori domain with t-dim R = n and with countably many prime v-ideals, then there is a chain of rings between R and R^w R1=R belong to R2……belong to Rn lohtuin in R^w such ... 详细信息

关键词： Strong Mori domain t-dimension w-integral closure

Langmuir-Blodgett Films with Bilayer Alternation of Hemicyanine Dye and Cadmium Stearate

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Chinese Physics Letters 1991年第11期8卷 603-606页

作者： J.Y.fang z.M.Sun S.J.Xiao z.H.Lu Y.Wei P.Stroeve Laboratory of Molecular and Biomolecular Electronics Southeast UniversityNanjing 210018 Laboratory of Solid State Microstructures Nanjing UniversityNanjing 210008 Department of Chemical Engineering University of CsdiforniaDavlsCA 95616U.S.A

Multilayers consisting of bilayer alternation of hemicyanine dye and cadmium stearate have been prepared by the Langmuir-Blodgett technique.x-ray diffraction and optical absorption spectra are used to characterixe thleir periodic structures and optical *** results show that a well ordered superlattice is produced and the hemicyanine dye is in non-aggregated formation in the alternating multilayers.

关键词： properties technique cyanine