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Journal of Hydrodynamics 2011年第5期23卷 625-636页

作者： SHAN Tie-bing YANG Jian-min LI Xin XIAO long-fei State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Shanghai 200240 China

This article mainly concentrates on a large-volume drilling semi-submersible platform, aiming to reveal wave run-up characteristics along square columns and give the relationship between air gap distributions and wave parameters. The tests with fixed model were conducted firstly on its encountering a series of monochromatic waves. A wide range of wave slope （H/L ） were selected to investigate the air gap response in detail. As can be seen, larger wave steepness will generally cause smaller air gap in the same wave period, which indicates nonlinear effects of incoming wave can amplify wave elevation. Model tests with mooring condition were also conducted in the same wave conditions. As was expected, the maximum relative wave elevation reduces obviously compared with the fixed one. However, wave shape close to columns show higher harmonic characteristics due to interaction between waves and the columns of semi-submersible platform. Meaningful conclusions from the model tests are drawn in this article, which is helpful in air gap design of floating offshore platform to a certain extent. In addition, the experimental results will provide an important reference for further research on validation and update of theoretical models of air gap.

关键词： wave run-up air gap diffraction-radiation effects wave steepness

Identification and geochemical significance of unusual C24 tetracyclic terpanes in Shahejie Formation source rocks in the Bozhong subbasin,Bohai Bay Basin

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Petroleum Science 2022年第5期19卷 1993-2003页

作者： Ning Wang Yao-Hui Xu fei-long Wang Yan Liu Qian Huang Xing Huang Key Laboratory of Exploration Technologies for Oil and Gas Resources Ministry of EducationYangtze UniversityWuhan430100China Hubei Key Laboratory of Petroleum Geochemistry and Environment(Yangtze University) Wuhan430100China Bohai Petroleum Research Institute Tianjin BranchCNOOC(China)Ltd.Tianjin300452China

C_(24)tetracyclic terpanes are common compounds in source rocks and crude oils,and C_(24)17,21-secohopane is the most common and widely used source-related *** this study,three unusual C_(24)tetracyclic terpanes were detected on the m/z 191 chromatogram of saturated hydrocarbons in the Shahejie Formation source rocks in the Bozhong *** on the mass spectra characteristics,diagnostic ion fragments,retention time and comparisons with published literature,three unusual C_(24)tetracyclic terpanes were identified as 10β(H)-des-A-oleanane,10β(H)-des-A-lupane and C_(24)*** the best of our knowledge,this is the first study to detect and publicly report these three compounds in source rock samples from the Shahejie Formation of the Bozhong subbasin,Bohai Bay *** results indicated that 10β(H)-des-A-oleanane and 10β(H)-des-A-lupane likely originated from terre strial angiosperms,while C_(24)des-A-hopane likely originated fro m prokaryotic o *** rrestrial angiosperms provide the material basis for the generation of compounds A and B,and the distribution and concentration of these two compounds are affected by thermal *** the low maturity stage(0.5%

关键词： Unusual tetracyclic terpanes 10β(H)-des-A-oleanane 10β(H)-des-A-lupane Geochemical significance Shahejie Formation Bozhong subbasin

Determination of diastereoisomeric alkaloids in urine by capillary electrophoresis with electrochemiluminescence detection

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Chinese Chemical Letters 2011年第2期22卷 197-200页

作者： Yan Ming Liu long fei Peng Lin Mei Li Juan Liu College of Chemistry and Chemical Engineering Xinyang Normal University Xinyang 464000 China Received 1 July 2010

A new and simple capillary electrophoresis with electrochemiluminescence detection was developed for the separation and the quantification of a pair of diastereoisomenc alkaloids（ephedrine and pseudoephedrine）.The limits of detection（S/N = 3） were 4.5×10^-8 mol/L for ephedrine and 5.2×10^-8 mol/L for pseudoephedrine,*** RSDs of migration time and peak area were less than 1.3 and 2.5%（n = 5）,*** applicability of the propose method was illustrated in the determination of ephedrine and pseudoephedrine in human urine,ephedrine in nasal drops,and the monitoring of pharmacokinetics for pseudoephedrine.

关键词： CE Electrochemiluminescence Alkaloids Urine analysis Pharmacokinetics

Synthesis and Crystal Structure of a 3-D Hydrogen-bonded Supramolecular Decavanadate Compound [Habo]_6[V_(10)O_(28)]·2C_3H_7OH·2H_2O

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Chinese Journal of Structural Chemistry 2005年第10期24卷 1186-1192页

作者： CHEN Lian LIN Zheng-Zhong JIANG fei-long YUAN Da-Qiang HONG Mao-Chun State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

A new inorganic-organic hybrid supramolecular compound [Habo]6[V10O28]·2C3H7OH·2H2O 1 （abo = R（-）-2-amino-1-butanol） has been synthesized from VO2^＋ in organic solvents and its crystal structure was reported as follows： monoclinic, space group P21/n, a = 11.419（9）, b = 16.811（16）, c = 15.521（12） A, β= 102.98（2）°, V= 2903（4） A^3, Z = 4, C15H46N3O19V5, Mr = 827.25, Dc = 1.893 g/cm^3, 2（MoKα） = 0.71073 A, μ = 1.636 mm^-1, F（000） = 1696, the final R = 0.0696 and wR = 0.1361 for 4641 observed reflections with I 〉 2σ（I）. The compound is based on decavanadate clusters [V10O28]^6-. The hydrogen bonding interactions among Habo^＋ cations, solvents and decavanadate clusters extend 1 into a three-dimensional supramolecular architecture.

关键词： decavanadate hydrogen bond three-dimensional crystal structure

Colorimetric detection of D-amino acids based on anti-aggregation of gold nanoparticles

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Chinese Chemical Letters 2014年第7期25卷 995-1000页

作者： long-fei Yuan Yu-Jian He Hong Zhao Ying Zhou Pei Gu College of Chemistry and Chemical Engineering University of Chinese Academy of Sciences State Key Laboratory of Natural and Biomimetic Drugs Peking University

A new method has been proposed to realize the visual detection of D-amino acids （DAAs） via the antiaggregation of 4-mercaptobenzoic acid modified gold nanoparticles （AuNPs） in the presence of D-amino acid oxidase （DAAO）. The negatively charged AuNPs were prepared using sodium citrate as a reducer and stabilizer. The presence of 4-mercaptobenzoic acid （4-MBA） and Cu2＋ induces the aggregation of AuNPs, resulting in a color change from ruby red to royal purple. However, DAAO could oxidize DAAs to generate H2O2. In the presence of H2O2, the mercapto （-SH） group in 4-mercaptobenzoic acid can be oxidized to form a disulfide （-S-S-） bond. Based on these facts, the pre-incubation of DAAs and 4-mercaptobenzoic acid with DAAO would significantly reduce the concentration of free 4-mercaptobenzoic acid molecules, thus the aggregation of AuNPs was interrupted since due to the lack of inducer. As the concentration of DAAs increases, the color of the AuNPs solution would progress from royal purple to ruby red. Consequently, DAAs could be monitored by the colorimetric response of AuNPs using a UV-vis spectrophotometer or even naked eyes. This DAAO mediated visual detection method could determine D- alanine （D-Ala） as a representative DAA with concentrations ranging from 1.5 × 10^-7mol L 1 to 3.0 × 10^-5 mol L^-1, and the detection limit was as low as 7.5 × 10^-8 mol L^-1. The proposed method is convenient, low-cost and free of complex equipment, making it feasible to analyze the concentration of D-AIa in real samples of β-amyloid peptide （Aβ1-42）.

关键词： Gold nanoparticles D-Amino acids D-Amino acid oxidase Anti-aggreagtion Colorimetric detection

Application of image alignment and time averaging methods in AFM detection for single DNA molecules

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Chinese Science Bulletin 2010年第16期55卷 1613-1618页

作者： WANG ChunMei SUN JieLin long fei ZHAO Jun HU Jun School of Life Science and Biotechnology Shanghai Jiao Tong University Shanghai 200240 China Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China

Enhancement of the SNR (signal to noise ratio) in single-molecule imaging is significantly important for improving image resolu-tion and distinguishing the fine structures of single molecules at a higher precision *** processing techniques have dem-onstrated the remarkable capability to improve the SNR and the resolution level by breaking through some inherent limitations unresolved by instrument hardware *** this paper, we focus on single-biomolecule imaging using atomic force mi-croscopy (AFM), a unique method in separated single-biomolecule imaging, and there was few suitable image processing tech-niques reported to increase the SNR of a single molecule’s AFM *** the typical samples of separately dispersed DNA molecules, we replaced the classified averaging method, which is usually used when the molecules’ structure can be easily and repeatedly prepared, with the time averaging method to improve the SNR in a single molecule’s AFM *** the time averaging technique with the image alignment method for the series of time-lapse AFM images of a single DNA molecule, we were able to improve the image’s SNR and recover some buried signals from the background ***, the fine structures of single molecules can potentially be further resolved if other image processing techniques are applied collaboratively with some newly developed imaging methods like Vibrating Mode Scanning Polarization Force Microscopy (VSPFM), and such combination will also be advantageous for the manipulation of single-biomolecules by *** addition, the proposed algorithms for the estimations of drift, distortion and SNR are applicable for quantitative status characterization of AFM imaging.

关键词：图象排列 DNA AFM 时间平均 SNR

A new way to measure the departure from thermodynamic equilibrium in stellar atmospheres

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Chinese Journal of Astronomy and Astrophysics 2009年第2期9卷 205-212页

作者： Zhong-Quan Qu long-fei Hao Xiao-Li Yan Cheng-Lin Xu Yunnan Astronomical Observatory/National Astronomical Observatories Chinese Academy of Sciences Kunming 650011 China Graduate School Chinese Academy of Sciences Beijing 100049 China Mathematics Department Yunnan Normal University Kunming 650122 China

A new way to measure the departure from thermodynamic equilibrium is proposed based on the departure factor which evaluates the deviation from a Boltzmann level distribution, used by Short and Hauschildt （2005） and others. The way is based on an explicit relationship describing the departure factor as a function of line to continuum source, dynamic temperature and line photon frequency, under three assumptions that the scattering can be neglected, the background continuum can be treated as a Planck function, and finally the complete redistribution can be true. It has the advantage that the departure can be very conveniently evaluated from the spectral analysis with only the radiative transfer involved. Some physical insights are recovered for some extreme cases. Some example calculations of the departure are presented for the quiet Sun, faint solar flare and strong solar flare for the generally used solar chromospheric lines： Hα, Hβ, CaII H, K and triplet. It is revealed that in the case of solar flares, the departure is less than thermodynamic equilibrium along the larger depth range than in the quiet sun due to chromospheric condensation. It becomes hard to distinguish the departures for the different lines of the same atom or ion. It is expected that this investigation can be constructive for studying stellar atmospheres in cases where the three assumptions are close to reality.

关键词： line formation -- radiative transfer -- stars atmospheres

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三维高熵合金的合成及其电解水应用研究进展

现代化工 2025年第1期45卷 17-23页

作者：王帅任李萍陈春迎王龙飞王奇陈新范金鹏陈杰中煤能源研究院有限责任公司陕西西安710054 西安交通大学化学工程与技术学院陕西西安710000

概述了三维高熵合金材料的合成方法及其在电催化分解水领域的应用研究进展。重点介绍了脱合金法和湿化学法合成三维高熵合金,以及多孔结构、凸立方型结构、介孔球的三维高熵合金在电催化分解水方面所取得的突破性进展。最后指出,三维高... 详细信息

概述了三维高熵合金材料的合成方法及其在电催化分解水领域的应用研究进展。重点介绍了脱合金法和湿化学法合成三维高熵合金,以及多孔结构、凸立方型结构、介孔球的三维高熵合金在电催化分解水方面所取得的突破性进展。最后指出,三维高熵合金的可控合成方法及其电催化水分解机制方面仍缺少系统性的梳理,在实际应用方面亟待寻找简易、高效的宏量制备方法。

关键词：高熵合金三维形貌析氢反应析氧反应协同效应

Genomic analysis of a pure culture of magnetotactic bacterium Terasakiella ***-1

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Journal of Oceanology and Limnology 2021年第6期39卷 2097-2106页

作者： Haijian DU Wenyan ZHANG Wei LIN Hongmiao PAN Tian XIAO long-fei WU College of Life Science Shandong UniversityQingdao 266237China CAS Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Ecology and Environmental Science Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Institutions of Earth Science Chinese Academy of SciencesBeijing 100029China France-China Joint Laboratory for Evolution and Development of Magnetotactic Multicellular Organisms Chinese Academy of SciencesBeijing 100029China Aix-Marseille University CNRSLCBMarseille F-13402France

Magnetotactic bacteria(MTB)display magnetotaxis ability because of biomineralization of intracellular nanometer-sized,membrane-bound organelles termed *** having been discovered more than half a century,only a few representatives of MTB have been isolated and cultured in the *** this study,we report the genomic characterization of a novel marine magnetotactic spirillum strain SH-1 belonging to the genus Terasakiella that was recently isolated.A gene encoding haloalkane dehalogenase,which is involved in the degradation of chlorocyclohexane,chlorobenzene,chloroalkane,and chloroalkene,was ***-1 genome contained cysCHI and soxBAZYX genes,thus potentially capable of assimilatory sulfate reduction to H_(2)S and using thiosulfate as electron donors and oxidizing it to *** of SH-1 also contained genes encoding periplasmic dissimilatory nitrate reductases(napAB),assimilatory nitrate reductase(nasA)and assimilatory nitrite reductases(nasB),suggesting that it is capable of gaining energy by converting nitrate to *** pure culture of Terasakiella ***-1 together with its genomic results off ers new opportunities to examine biology,physiology,and biomineralization mechanisms of MTB.

关键词： magnetotactic bacteria magnetotaxis pure culture comparative genomic analysis

Enhanced strength-plasticity synergy of copper composites by designing uniformly dispersed yttria nanoparticles and a heterogeneous grain structure

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Rare Metals 2024年第12期43卷 6704-6716页

作者： Xue-Hui Zhang Hai-Xiang Yuan fei Huang Hang Wang Bin Yang long-fei Zeng Xin-Hao Li Ya-Jian Huang Tahir Ahmad School of Materials Science and Engineering Jiangxi University of Science and Technology Periodical Press Jiangxi University of Science and Technology College of Rare Earth Jiangxi University of Science and Technology College of Engineering and Emerging Technologies University of the Punjab

Designing heterogeneous grain structure（HGS）has been proven to be an effective strategy for overcoming the strength-plasticity dilemma in copper and copper ***,the construction of HGS in dispersionstrengthened copper（DSC） for enhancing strength-plasticity synergy remains ***,we proposed a novel method,multistep ball milling and reduction process followed by spark plasma sintering,to prepare DSC with an HGS to ameliorate the strength-plasticity dilemma in ***-and nano-CuO and nano-Y2O3powders were chosen as raw materials in this new *** Cu-7vol% Y2O3composite,exhibiting a compressive yield strength of 438 MPa and a failure strain of 46.3%,exhibits a superior strength-plasticity tradeoff in comparison with other DSC *** experiments indicate that the back-stress at the heterointerfaces between coarse grains and fine grains maybe not only raise the yield strength of Cu-Y2O3composite,but also significantly enhance the strain hardening to increase the plasticity of the *** new HGS designing route in this study offers a feasible pathway to develop DSC with a remarkable enhancement in strength and plasticity.

关键词： Dispersion strengthened copper Heterogeneous grain structure Multistep ball milling and reduction Strength-plasticity synergy