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Rapid Determination of Ranitidine in Human Plasma by Liquid Chromatography-Tandem Mass Spectrometry and Its Application to a Clinical Pharmacokinetic Study

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Chemical Research in Chinese Universities 2010年第6期26卷 910-914页

作者： ZHANG Chao WANG Lu GUAN Xin J. Paul Fawcett ZHAO Li-mei sun yan-tong GU Jing-kai Research Center for Drug Metabolism College of Life Science Jilin University Changchun 130021 P R. China Liaoning Province Academy of Analytic Science Shenyang 110015 P. R. China School of Pharmacy University of Otago PO Box 56 Dunedin New Zealand Second Clinical Hospital Affiliated to the Chinese Medical University Shenyang 110004 P. R. China

A rapid and sensitive assay based on high performance liquid chromatography-tandem mass spectrometry（LC-MS/MS） was developed for the determination of ranitidine（RAN） in human plasma with codeine as internal standard（IS）.After protein precipitation with acetonitrile,the analyte and IS were separated on a Zorbax SB-Aq C18 column（150 mm×4.6 mm i.d.,5 μm） eluted with a mobile phase consisting of methanol/acetonitrile/10 mmol/L ammonium acetate containing 1% formic acid（pH=2.4）（volume ratio 12.5：12.5：75） at a flow rate of 1.0 mL/*** was performed by electrospray ionization in the positive ion mode followed by the multiple reaction monito-ring（MRM） of the transitions of RAN at m/z 315.1→176.3 and of IS at m/z 300.1→*** method was linear over a concentration range of 1―1000 ng/mL（r=0.9991） with a lower limit of quantitation（LLOQ） of 1 ng/mL and a limit of detection（LOD） of 0.3 ng/*** as relative error was from-0.01% to-1.7% and intra-day and inter-day precisions as relative standard deviation were ≤8.9% and ≤5.5%,*** method was successfully applied to a pharmacokinetic study of ranitidine,getting a single oral dose（160 mg） to healthy volunteers.

关键词： Ranitidine Pharmacokinetics Human plasma Protein precipitation LC-MS/MS

Rapid Quantification of Astilbin in Rat Plasma by Liquid Chromatography-tandem Mass Spectrometry and Its Application to Pharmacokinetic Study

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Chemical Research in Chinese Universities 2013年第6期29卷 1078-1082页

作者： YIN Lei ZHANG Yun-hui ZHAO Sen CHENG Long-mei SHI Mei-yun yanG yan sun yan-tong LIU Xi-dong FAWCETT J. Paul School of Life Sciences Jilin University Changchun 130012 P.R.China Clinical Pharmacology Center Research Institute of Translational Medicine the First Hospital of Jilin University Changchun 130061 P.R.China National Engineering Laboratory for AIDS Vaccine the Ministry of EducationJilin University Changchun 130012 P.R.China Key Laboratory for Molecular Enzymology and Engineering the Ministry of EducationJilin University Changchun 130012 P.R.China School of Pharmaceutical Sciences Jilin University Changchun 130021 P. R. China School of Pharmacy University of Otago Dunedin 9054 New Zealand

Astilbin is a potential immunosuppressive agent with minor cytotoxicity. Its oral bioavailability is supposed to be rather low and therefore a sensitive analytical method is required for its pharmacokinetic study after oral administration. A simple, sensitive and rapid liquid chromatography-tandem mass spectrometry（LC-MS/MS） method was developed and validated for the determination of astilbin in rat plasma. Plasma samples were subjected to liquid-liquid extraction with ethyl acetate and separated by reversed phase high performance liquid chromatography（HPLC） with methanol-0.01%（volume fraction） formic acid（50：50, volume ratio） as mobile phase. Quantitive determination was achieved on negative LC-MS/MS by a multiple reaction moitoring method with transitions m/z 449.1→150.9（quantifier） and m/z 449.1→284.9（qualifier） for astilbin and m/z 128.9→42.0 for internal standard（IS）. A lower limit of quantification（LLOQ） of ng/mL was achieved within a short cycle time of 3.4 min. The method was successfully applied to a pharmacokinetic study involving oral and intravenous administrations of 6 mg/kg astilbin to six rats.

关键词： Astilbin Liquid chromatography-tandem mass spectrometry(LC-MS/MS) Pharmacokinetics Rat Plasma

Boosting hydrocarbon conversion via Cu-doping induced oxygen vacancies on CeO2 in CO2 electroreduction

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Journal of Energy Chemistry 2025年第1期100卷 66-76页

作者： Lei Xue tong Shi Chenhui Han Heng Zhang Fenrong Liu Haorun Li yan Wang Xiaojun Gu Shanghong Zeng Inner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials School of Chemistry and Chemical Engineering Inner Mongolia University State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Institute of Catalysis Department of Chemistry Zhejiang University National Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization Baotou Research Institute of Rare Earths

Conversion of CO2back to hydrocarbons is the most direct way of closing the“carbon cycle”,and its significance is further enlarged if this process is driven by renewable energies such as ***,precisely controlling the product selectivity towards hydrocarbons against the competitive hydrogen evolution remains challenging,especially for Cu-based ***,we report a novel defect engineering strategy,by which Cu-doping-induced oxygen vacancies on CeO2nanorods were effectively created,with adjustable vacancy/Cu *** resulting optimum catalyst shows up to 79% catalytic current density to hydrocarbons （excluding CO）,with 49% faradaic efficiency to *** and density functional theory unveil that the ratio between oxygen vacancy and Cu affects significantly the formation of*CHO and activation of H2O,which leads to the following deep hydrogenation to *** findings may spur new insights for designing and developing more controllable chemical process relevant to CO2utilization.

关键词： Oxygen vacancy Hydrocarbon production Reaction mechanism

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鸡胚脑细胞谷氨酸释放的模拟微重力效应

生物化学与生物物理进展 2002年第1期29卷 128-132页

作者：王彦孙彤张锦珠中国科学院生物物理研究所北京100101

用回转器旋转鸡胚蛋研究对脑细胞的模拟微重力生物效应 .采用连续荧光法测量孵化 10d (E10 )和孵化13d (E13)鸡胚的脑细胞谷氨酸的初始释放速率、在KCl去极化及单个电脉冲刺激后的释放速率和释放量以及谷氨酸的含量 ,并对旋转处理组和... 详细信息

用回转器旋转鸡胚蛋研究对脑细胞的模拟微重力生物效应 .采用连续荧光法测量孵化 10d (E10 )和孵化13d (E13)鸡胚的脑细胞谷氨酸的初始释放速率、在KCl去极化及单个电脉冲刺激后的释放速率和释放量以及谷氨酸的含量 ,并对旋转处理组和静止对照组进行了比较 .结果如下 :旋转组和对照组脑细胞的谷氨酸初始释放速率没有显著差异 ,E10鸡胚经 2 4h旋转后 ,在KCl刺激下脑细胞的谷氨酸释放速率和释放量皆高于对照组 ,经 4h旋转后谷氨酸含量显著增高 (P <0 0 1) ;但旋转 2 4h的E13鸡胚上述指标皆无显著改变 ,表明微重力对鸡胚脑细胞神经递质释放的影响与胚龄有关 .鸡胚脑细胞在电脉冲刺激下谷氨酸释放的动态过程表明 :脉冲电场引起的谷氨酸释放与细胞内钙离子迅速增加有关 .

关键词：微重力生物效应鸡胚脑细胞谷氨酸释放

A Novel Model for Describing Rail Weld Irregularities and Predicting Wheel-Rail Forces Using a Machine Learning Approach

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 555-577页

作者： Linlin sun Zihui Wang Shukun Cui Ziquan yan Weiping Hu Qingchun Meng State Key Laboratory of High-Speed Railway Track System China Academy of Railway Sciences Corporation LimitedBeijing100081China Railway Engineering Research Institute China Academy of Railway Sciences Corporation LimitedBeijing100081China School of Aeronautic Science and Engineering Beihang UniversityBeijing100191China

Rail weld irregularities are one of the primary excitation sources for vehicle-track interaction dynamics in modern high-speed *** can cause significant wheel-rail dynamic interactions,leading to wheel-rail noise,component damage,and *** researchers have employed the vehicle-track interaction dynamic model to study the dynamic interactions between wheel and rail induced by rail weld geometry ***,the cosine wave model used to simulate rail weld irregularities mainly focuses on the maximum value and neglects the geometric *** this study,novel theoretical models were developed for three categories of rail weld irregularities,based on measurements of the high-speed railway from Beijing to *** vertical dynamic forces in the time and frequency domains were compared under different running *** forces generated by the rail weld irregularities that were measured and modeled,respectively,were compared to validate the accuracy of the proposed ***,based on the numerical study,the impact force due to rail weld irrregularity is modeled using an Artificial Neural Network(ANN),and the optimum combination of parameters for this model is *** results showed that the proposed model provided a more accurate wheel/rail dynamic evaluation caused by rail weld irregularities than that established in the *** ANN model used in this paper can effectively predict the impact force due to rail weld irrregularity while reducing the computation time.

关键词： Rail weld irregularity high-speed railway vehicle-track coupled dynamics wheel/rail dynamic vertical force artificial neural networks

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论动词与构式的动态作用力关系

林区教学 2017年第4期 44-45页

作者：孙彦彤哈尔滨师范大学西语学院

构式是形式和意义的匹配,动词能投射自身的题元结构并与构式具有特定关系。Goldberg把动词和构式的关系界定为：增添,动态作用力,前提条件和同时进行的行为或动作。动态作用力就是动词的意义与构式的意义通过一定的动态作用力而把二者... 详细信息

构式是形式和意义的匹配,动词能投射自身的题元结构并与构式具有特定关系。Goldberg把动词和构式的关系界定为：增添,动态作用力,前提条件和同时进行的行为或动作。动态作用力就是动词的意义与构式的意义通过一定的动态作用力而把二者合为一的关系,分析动词与构式存在动态作用力关系背后的物理现实及心理表征时间等原因,以理解动词和构式的互动关系。

关键词：动词构式动态作用力

考虑运动学误差的框架锯主运动系统动力学分析

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组合机床与自动化加工技术 2022年第4期 148-152页

作者：孙同岩张进生孙德鹏山东大学机械工程学院济南250061 山东大学高效洁净机械制造教育部重点实验室济南250061 山东省石材工程技术研究中心济南250061

针对框架锯主运动系统双连杆长度误差引起的锯框运动稳定性、可靠性差,造成石材板材加工形面精度低的问题,考虑主运动系统运动学误差,探究其动力学参数变化规律。以双连杆长度存在误差的主运动系统为研究对象,建立了主运动系统的运动学... 详细信息

针对框架锯主运动系统双连杆长度误差引起的锯框运动稳定性、可靠性差,造成石材板材加工形面精度低的问题,考虑主运动系统运动学误差,探究其动力学参数变化规律。以双连杆长度存在误差的主运动系统为研究对象,建立了主运动系统的运动学模型,并基于达朗贝尔原理建立了动力学模型。基于MATLAB分别对运动学与动力学模型进行了求解,分析了运动误差的变化规律,并得出了连杆长度误差对其受力的影响特性。研究结果表明,将各构件x和y方向受力独立分析,较传统仿真分析方法精确度提高了15.49%;锯框加速度的变化影响主运动系统各构件的受力,连杆长度误差的存在导致其加速度存在偏差(0.096 m/s;),且连杆受力随加速度幅值的增大逐渐增大(1200 N)。

关键词：主运动系统误差分析运动学动力学 MATLAB

区域经济发展中的金融支持研究——以“蓝黄两区”为例

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山东财政学院学报 2014年第1期 5-17页

作者：孙国茂孙同岩山东高校资本市场创新发展协同创新中心山东济南250002 济南大学经济学院山东济南250002

基于金融发展与经济增长关系研究的理论,选取"蓝黄两区"1978-2011年间经济增长和金融发展的相关历史数据,通过单位根检验、协整检验、Granger检验和脉冲响应函数分析等方法实证检验了"蓝黄两区"金融发展对经济增长的支持效果。结果表明... 详细信息

基于金融发展与经济增长关系研究的理论,选取"蓝黄两区"1978-2011年间经济增长和金融发展的相关历史数据,通过单位根检验、协整检验、Granger检验和脉冲响应函数分析等方法实证检验了"蓝黄两区"金融发展对经济增长的支持效果。结果表明,改革开放以来,"蓝黄两区"金融发展与经济增长存在负向关系,金融发展没有很好地发挥对经济增长的促进作用,而且存在金融抑制的现象。基于实证检验结果,"两区"金融业发展滞后的根本原因在于其经济增长方式的制约和金融制度性缺陷。可从优化金融市场结构、改善金融生态环境、建立区域金融中心等方面提高"两区"金融支持能力。

关键词： “蓝黄两区” 经济增长金融支持

液-质联用法研究磷霉素钙在健康人体的生物等效性

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中国医院药学杂志 2011年第1期31卷 5-8页

作者：孙严彤王利君褚扬韩江彬魏岩吉林大学药物代谢研究中心吉林长春130021 吉林大学药学院吉林长春130021 长春市公安局司法鉴定中心吉林长春130021

目的：建立液-质联用法测定人血浆中磷霉素钙的浓度，研究磷霉素钙的人体药动学及生物等效性。方法：血浆样品中加入内标阿德福韦，经乙腈蛋白沉淀，SB-Aq C18色谱柱进行分离，流动相流速为1．0mL·min^-1,梯度洗脱方式，采用多反应监测... 详细信息

目的：建立液-质联用法测定人血浆中磷霉素钙的浓度，研究磷霉素钙的人体药动学及生物等效性。方法：血浆样品中加入内标阿德福韦，经乙腈蛋白沉淀，SB-Aq C18色谱柱进行分离，流动相流速为1．0mL·min^-1,梯度洗脱方式，采用多反应监测（MRM）的负离子方式检测。结果：在100～25000μg·L^-1范围内呈良好的线性关系，日内及日间精密度（RSD）小于8％。受试制剂和参比制剂的tmax分别为（1．8±0．2）h和（2．4±0．5）h，（Cmax分别为（6034．0±1540．9）μg·L^-1和（6182．5±1221．4）μg·L^-1，AUG0-t分别为（43755．6±7198．0）μg·h·L^-1。和（43720．1±9134．2）μg·h·L^-1。结论：本法准确，灵敏无杂质干扰。两种制剂生物等效。

关键词：磷霉素钙液相色谱-串联质谱法生物等效性