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Chinese Chemical Letters 2007年第2期18卷 201-204页

作者： Bin Guan dong xing yuan Environmental Science Research Center Xiamen University Xiamen 361005 China

A simple, fast and reliable method, using high performance anion chromatography with pulsed amperometric detection, had been developed for the analysis of neomycin in water samples. The elution and separation were carried out with an isocratic mobile phase, containing 10 mmol/L NaOH. The influence of the concentration and pH of the mobile phase on the separation and detection was investigated. A quadruple-potential waveform used for the detection was optimized. The detection limit of neomycin was down to 0.027 μg/mL. The linearity of neomycin calibration curve ranged from 0.050 to 0.505 μg/mL with correlation coefficient of 0.9997. R.S.D. (n = 11) was 4.0%.

关键词： Neomycin High performance anion chromatography Pulsed amperometric detection

Kinetics and products of ozonation of *** Red 195 in a semi-batch reactor

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Chinese Chemical Letters 2015年第1期26卷 93-99页

作者： Rui Zhang dong-xing yuan Bao-Min Liu College of the Environment & Ecology Xiamen University State Key Laboratory of Marine Environmental Science Xiamen University

Textile wastewater shows great threats to the environment if not well pretreated before discharge. A promising technique, ozonation, was applied to remove the color in dye solutions containing C.I. Reactive Red 195 （RR195） in a semi-batch reactor. The decolorization of RRI95 by the ozone process followed pseudo-first-order kinetics. Several factors which influenced the efficiency of decolorization were studied and the reaction rate constant （k） obtained with different operational parameters was compared. Our results showed that RRI95 was more easily degraded in acidic than in alkaline conditions. The dyeing auxiliaries （sodium carbonate and sodium chloride） that acted as radical scavengers could enhance the decolorization process, and the ozonation time for total color removal lengthened if the initial dye concentration was higher. The analysis of the ozonation products was performed by liquid chromatography-tandem mass spectrometer and a possible degradation pathway was predicted according to the ozonation products and structure of RR195. Our results indicated that ozonation was effective in the color removal of dyes, but further treatment might be necessary since the ozonation products are high toxic.

关键词： Ozonation C.I. Reactive Red 195 Decolourization Kinetics Degradation pathway

Determination of sulfite in water samples by flow injection analysis with fluorescence detection

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Chinese Chemical Letters 2010年第12期21卷 1457-1461页

作者： Li Qian Yin dong xing yuan Min Zhang State Key Laboratory of Marine Environmental Science Environmental Science Research Centre Xiamen University Xiamen 361005 China

A fast,sensitive,and reliable method for the determination of sulfite（SO3^2-） in fresh water and seawater samples was *** proposed method was based on the reaction of o-phthalaldehyde（OPA）-sulfite-NH_3 in alkaline solution,with flow injection analysis and fluorescence *** experimental parameters were investigated in pure water and seawater matrixes. The detection limits（S/N = 3） were 0.006μmol/L in pure water and 0.018μmol/L in seawater for SO3^2-.The method was successfully applied to analyze SO3^2- iin the samples of rain water and flue gas desulfurization seawater.

关键词： Sulfite Fluorophotometry FIA Flue gas desulfurization seawater Rainwater

Sequential analysis of dimethyl sulfur compounds in seawater

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Chinese Chemical Letters 2007年第1期18卷 99-102页

作者： Meng Li dong xing yuan Quan Long Li Xiao Ying Jin State Key Lab of Marine Environmental Science Xiamen University Environmental Science Research Centre of Xiamen University Xiamen 361005 China

A sequential method for the determination of dimethyl sulfur compounds, including dimethylsulfide （DMS）, dimethylsulfonio- propionate （DMSP） and dimethylsulfoxide （DMSO）, in seawater samples has been developed. Detection limit of 2.5 pmol of DMS in 25 mL sample, corresponding to 0.10 nmol/L, was achieved. Recoveries for dimethyl sulfur compounds were in the range of 68.6- 78.3%. The relative standard deviations （R.S.D.s） for DMS, DMSP and DMSO determination were 3.0, 5.4 and 7.4%, respectively.

关键词： Dimethylsulfide (DMS) Dimethylsulfoniopropionate (DMSP) Dimethylsulfoxide (DMSO) Purge and trap Microwave irradiation Sequential analysis

The Wear Process of PTFE Coatings Under Vacuum Conditions

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Journal of Harbin Institute of Technology(New Series) 2014年第1期21卷 121-124页

作者： xing-dong yuan Yong Liu De-Zhuang Yang Shi-Yu He School of Materials Science and Engineering Shandong Jianzhu University Space Material and Environment Engineering Lab. Harbin Institute of Technology

The wear process of PTFE coatings sliding against GCr15-bearing steel ball under vacuum conditions was investigated,and the hardness of the PTFE coatings on both sides of wear track was measured. The experimental results showed that the friction coefficient of the PTFE coatings increases with the increase of sliding distance under different sliding velocities. And the friction coefficient of the PTFE coatings increases with the increase of sliding distance under different sliding loads. The wear rate of PTFE coatings decreases with the increase of sliding distance. And the majority of the wear produced during the whole wear process of PTFE coatings sliding against GCr-15 steel ball comes from the early period of friction. The hardness of PTFE coatings on both sides of wear track increases as the distance increases and distributes symmetrically around the wear track. Scanning electron microscope( SEM) was utilized to investigate the worn surface of PTFE coating. It was found that the worn surface of PTFE coating is characterized by sever plastic deformation and spalling of the PTFE coating. The edge of wear track is characterized by micro cracking.

关键词： sliding wear two-body abrasion polymers high vacuum

Analysis of Transition Mechanism of Cubic Boron Nitride Single Crystals under High Pressure-High Temperature with Valence Electron Structure Calculation

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Chinese Physics Letters 2019年第1期36卷 10-13页

作者： Mei-Zhe Lv Bin Xu Li-Chao Cai Feng Jia xing-dong yuan School of Materials Science and Engineering Shandong University School of Materials Science and Engineering Shandong Jianzhu University

The possibilities of hexagonal boron nitride(hBN) and lithium boron nitride(Li_3BN_2) transition into cubic boron nitride(cBN) under synthetic pressure 5.0 GPa and synthetic temperature 1700 K are analyzed with the use of the empirical electron theory of solids and molecules. The relative differences in electron density are calculated for dozens of bi-phase interfaces hBN/cBN, Li_3BN_2/cBN. These relative differences of hBN/cBN are in good agreement with the first order of approximation(<10%), while those of Li_3BN_2/cBN are much greater than 10%.This analysis suggests that Li_3BN_2 is impossible to be intermediate phase but is a catalyst and cBN should be directly transformed by hBN.

关键词： Transition Mechanism Cubic Boron Valence Electron Structure Calculation

PRECONCENTRATION OF TRACE ZINC IN SEAWATER ON CPPI RESIN BY FIA AND ON-LINE DETECTION BY ICP-AFS

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Chinese Chemical Letters 1990年第3期1卷 237-238页

作者： dong xing yuan Peng yuan YANG Xiao Ru WANG Ben Li HUANG Department of Chemistry,Xiamen University,Xiamen,361005

A quite new type of chelating resin Carboxymethylated Polyethylenimine-Polymethylenepolyphenylene Isocyanate(CPPI)is used for the preconcentration of Zn from high salt water such as seawater. The preconcentration is controlled through the technique of Flow Injection Analysis(FIA).The concentrated sample solution is then directly transferred to an Inductively Coupled Plasma-Atomic Fluorescence Spectrometer(ICP-AFS)for *** detection limit of Zn by the technique is about 0.06 ppb.

关键词： CPPI PRECONCENTRATION OF TRACE ZINC IN SEAWATER ON CPPI RESIN BY FIA AND ON-LINE DETECTION BY ICP-AFS FIA ICP LINE

龙门山后山断裂中段汶川-茂县断裂的晚第四纪活动性分析

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地震地质 2017年第3期39卷 572-586页

作者：王旭光李传友吕丽星董金元中国地震局地质研究所活动构造与火山重点实验室100029

龙门山断裂带位于青藏高原东缘与四川盆地交界处,构造位置非常重要,对中国西南地区地形地貌、地质构造以及地震的发生等影响深远。通过卫星影像解译以及野外调查,初步分析认为岷江在汶川-茂县断裂区段主要发育5级阶地。结合前人研究获... 详细信息

龙门山断裂带位于青藏高原东缘与四川盆地交界处,构造位置非常重要,对中国西南地区地形地貌、地质构造以及地震的发生等影响深远。通过卫星影像解译以及野外调查,初步分析认为岷江在汶川-茂县断裂区段主要发育5级阶地。结合前人研究获得的阶地年龄,文中将T_1—T_5阶地年龄分别限定在3~10ka、约20ka、40~50ka、60ka和80ka。另外,通过对区域内断裂沿线的阶地、冲沟等地质地貌的野外调查,结合卫星影像解译和差分GPS测量等工作,认为汶川-茂县断裂在T_3阶地(40~50kaBP)形成后、T_2阶地(约20ka BP)形成前有过活动,而在T_2阶地形成以来不再活动。结合中央断裂、前山断裂均为全新世活动断裂的认识,推测龙门山断裂带的活动已转移到更靠近盆地的中央断裂和前山断裂上。

关键词：河流阶地断裂活动性汶川-茂县断裂龙门山断裂带

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DynaCT在间接门静脉造影中的应用探讨

中国临床医学影像杂志 2015年第4期26卷 297-299页

作者：董兴元赵罡卢再鸣中国医科大学附属盛京医院辽宁沈阳110004

目的:探讨Dyna CT技术在肝脏间接门静脉造影中的应用价值。方法:选取32例肝脏肿瘤介入治疗患者,在行常规DSA间接门静脉造影后进行旋转数字造影采集,并行Dyna CT重建以观察门静脉显影情况。结果 :32例患者中,门静脉显影30例,因门静脉左... 详细信息

目的:探讨Dyna CT技术在肝脏间接门静脉造影中的应用价值。方法:选取32例肝脏肿瘤介入治疗患者,在行常规DSA间接门静脉造影后进行旋转数字造影采集,并行Dyna CT重建以观察门静脉显影情况。结果 :32例患者中,门静脉显影30例,因门静脉左支或右支有瘤栓部分不显影者2例,Dyna CT重建得到的影像比常规DSA间接门静脉造影看到的门静脉走行更清晰。结论:应用Dyna CT技术可以在术中很好地显示门静脉及其分支,更清晰显示门静脉对肝脏的供血情况,比常规DSA间接门静脉造影显示门静脉更具优势。所以该技术在间接门静脉造影中具有非常高的临床实用价值。

关键词：体层摄影术,X线计算机门静脉造影术

Insight Into the Separation-of-Variable Methods for the Closed-Form Solutions of Free Vibration of Rectangular Thin Plates

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 329-355页

作者： Yufeng xing Ye yuan Gen Li Institute of Solid Mechanics Beihang University(BUAA)Beijing100191China

The separation-of-variable(SOV)methods,such as the improved SOV method,the variational SOV method,and the extended SOV method,have been proposed by the present authors and coworkers to obtain the closed-form analytical solutions for free vibration and eigenbuckling of rectangular plates and circular cylindrical *** taking the free vibration of rectangular thin plates as an example,this work presents the theoretical framework of the SOV methods in an instructive way,and the bisection–based solution procedures for a group of nonlinear eigenvalue ***,the explicit equations of nodal lines of the SOV methods are presented,and the relations of nodal line patterns and frequency orders are *** is concluded that the highly accurate SOV methods have the same accuracy for all frequencies,the mode shapes about repeated frequencies can also be precisely captured,and the SOV methods do not have the problem of missing roots as well.

关键词： Separation-of-variable method Rayleigh quotient nodal line eigenvalue equation bisection method