75 research outputs found

    Flooding Efficiency of Flooding systems and Wettability Study on the Simulaitn Rock Surface

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    为了研究驱油体系在模拟岩芯表面的润湿性,为微重力应用研究提供依据,选择胜利纯梁采油厂c6—41井原油,应用正交实验设计,通过最低瞬时界面张力测定,筛选出阴离子表面活性剂sDc—V、非离子表面活性剂FBB、HPAM和复碱的驱油体系配方.开展室内模拟驱油实验,同时测定驱油体系溶液对模拟岩芯的接触角,并且关联驱油效率和接触角之间的关系,发现驱油效率越高,接触角值越小

    第十八届美国理论与应用力学大会总结

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    1会议概况2018年6月5—9日,第18届美国理论与应用力学大会(18th U.S. National Congress of Theoretical and Applied Mechanics, USNCTAM2018)在美国芝加哥召开.本次大会由美国力学国家委员会和中国力学学会联合主办,旨在探讨和交流近四年世界范围内在理论和应用力学领域的基础研究、创新技术的最新进展,吸引了来自世界各地的近千名专家学

    Effects of Temperature on the Intercalation-Deintercalation Process of Lithium Ion in the Spinel LiMn_2O_4

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    E-mail: [email protected], [email protected][中文文摘]运用电化学阻抗谱研究了商品化尖晶石LiMn2O4电极在1mol/L LiPF6-EC(碳酸乙烯酯):DEC(碳酸二乙酯)电解液中―10~30℃范围内的阻抗谱特征、固体电解质相界面(SEI)膜阻抗、电子电阻和电荷传递电阻等随温度的变化.研究结果表明,尖晶石LiMn2O4电极的阻抗谱特征与温度有关,随温度的升高,与活性材料电子电导率相关的半圆和与SEI膜相关的半圆会发生重叠而成为一个半圆.通过选取适当的等效电路拟合了实验所得的电化学阻抗谱数据,测得尖晶石LiMn2O4电极在1mol/LLiPF6-EC:DEC电解液中,锂离子迁移通过SEI膜的离子跳跃能垒平均值为15.49kJ/mol;电子电导率的热激活化能平均值为24.21kJ/mol;嵌入反应活化能平均值为53.07kJ/mol。[英文文摘]Variations of impedance spectra,electronic resistance,and the resistances of the solid electrolyte interphase(SEI) film,as well as the charge transfer reaction of commercially spinel LiMn2O4 electrode were investigated by electrochemical impedance spectroscopy(EIS) in 1 mol/L LiPF6-EC(ethylene carbonate):DEC(diethyl carbonate) electrolyte solutions with the temperature in the range of-10~30 ℃.It is found that,the common EIS features of spinel LiMn2O4 electrode are related to the temperature,the semicircles observed in the Nyquist diagram which related to the electronic conductivity of the material and the semicircles related to the SEI film become to overlap each other to form one semicircle at higher temperatures. The experimental EIS data was simulated by a suitable equivalent circuit that includes elements related to the electronic and ionic transport in addition to the charge transfer process. In 1 mol/L LiPF6-EC:DEC electrolyte solutions, the energy barriers for the ion jump relating to migration of lithium ions through the SEI film of the spinel LiMn2O4 electrode were determined to be 15.49 kJ/mol, the thermal active energy of the electronic conductivities to be 24.21 kJ/mol, and the intercalation-deintercalation reaction active energies to be 53.07 kJ/mol, respectively.国家重点基础研究和发展规划(No2009CB220102);中国矿业大学青年科技基金(NoON080282),中国矿业大学人才引进经费(NoZX280),中国矿业大学科技攀登计划(NoON090237)资助项

    Diagnosis of Electrochemical Impedance Spectroscopy in Lithium Ion Batteries

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    Corresponding author e-mail: [email protected]; [email protected][中文文摘]电化学阻抗谱(EIS)是研究电极/电解质界面发生的电化学过程的最有力工具之一,广泛应用于研究锂离子在锂离子电池嵌合物电极活性材料中的嵌入和脱出过程。本文从分析嵌合物电极的EIS谱特征入手,探讨了电化学阻抗谱中各时间常数的归属问题,重点讨论了与锂离子嵌脱过程相关的动力学参数,如电荷传递电阻、活性材料的电子电阻、扩散以及锂离子扩散迁移通过固体电解质相界面膜(SEI膜)的电阻等,对电极极化电位和温度的依赖关系。[英文文摘]Electrochemical impedance spectroscopy(EIS) is one of the most powerful tools to analyze electrochemical processes occurring at electrode/electrolyte interfaces,and has been widely used to analyze the insertion /desertion process of lithium ion in the intercalation electrode for lithium ion battery.In this paper,the ascription of each time constant of EIS spectra is discussed,based on analyzing the common EIS features of intercalation electrode.The kinetic parameters in the lithium ion insertion/desertion,desertion,dependent on temperature and electrode polarization,such as the charge transfer resistance,the electronic resistance of activated material,the resistance of SEI film that lithium ion transferring through,are also discussed based on the theoretical analysis.国家重点基础研究发展计划(973)项目(No.2009CB220102);中国矿业大学青年科技基金项目(No.ON080282)资

    Y型聚乙二醇干扰素琢-2b注射液治疗HCV基因2/3型慢性丙型肝炎患者疗效和安全性的多中心随机对照试验研究

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    目的以标准剂量的聚乙二醇干扰素(Peg IFN)α-2a联合利巴韦林作为阳性对照,评价新型试验药物Y型Peg IFNα-2b注射液联合利巴韦林治疗2型/3型慢性丙型肝炎(CHC)患者的疗效和安全性。方法采用多中心、随机开放、阳性药对照的Ⅲ期临床试验,筛选符合要求的2型/3型CHC患者,按照2:1的比例随机分配到Y型Peg IFNα-2b组和Peg IFNα-2a组,同时口服利巴韦林,疗程24 w,停药随访24 w。采用Abbott Real Time HCV Genotype II检测HCV基因型,采用Cobas Taq Man实时定量PCR法检测血清HCV RNA水平。详细记录不良事件。主要疗效指标为持续病毒学应答(SVR),并进行非劣效检验。结果本试验实际入组2型/3型CHC患者255例,实际治疗241例。全分析集(FAS)数据显示,158例试验组和83例对照组患者SVR分别为85.4%(95%CI 79.94%~90.94%)和79.5%(95%CI 70.84%~88.20%,P=0.2402);对符合方案分析集(PPS)人群分析显示,试验组和对照组患者SVR分别为87.9%(95%CI 82.45%~93.27%)和85.9%(95%CI 77.82%~94.01%,P=0.7060),率差的95%可置信区间均符合非劣效标准;对PPS人群分析显示,85.8%受试者获得了早期病毒学应答(RVR),RVR的阳性预测值为90.1%;试验组和对照组不良事件发生率相似,分别为95.6%和95.2%,严重不良事件发生率分别为3.8%和3.6%。结论应用Peg IFNα联合利巴韦林治疗2型/3型CHC患者,新型试验药物Y型Peg IFNα-2b具有与对照药物Peg IFNα-2a相似的疗效和安全性。国家科技部“十二五”重大专项(编号:2012ZX10002-003);“重大新药创制”十二五科技重大专项(编号:2012ZX09303019)

    旋转振动圆柱绕流周期解和Floquet稳定性

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    对低雷诺数旋转振动圆柱绕流问题运用低维Galerkin方法将N-S方程约化为一组非线 性常微分方程组.运用打靶法数值求解了这组方程的周期解,并用 Floquet理论对周期解的稳 定性进行了分析,研究了流动失稳的机制

    Centrifuge modeling of cyclic loading induced by ice sheet

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    前言吸力式基础的应用起源于欧洲,最初用作浮动结构的稳固基础,1994年欧洲Europipe16/-11E第一次将海洋采油平台建在吸力式基础上[1].…

    Effect of Electrolytes on Kinetic Behavior of Colloidal Dispersions of Mg-Al Hydrotalcite-Like Compounds

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    采用动态光散射法研究了电解质对Mg-A1类水滑石(HTlc)溶胶聚集动力学行为的影响,发现随惰性电解质(NaCl,NaNO3)浓度的增大,Mg-A1 HTlc溶胶经历稳定、慢速聚集和快速聚集三个区域,而特性吸附电解质(NaOH)在所研究的浓度范围(0~4 mmol/L)内未观察到快速聚集.NaCl和NaNO3的临界聚沉浓度分别为127和180mmol/L,慢速聚集区稳定比与NaCl,NaNO3和NaOH浓度间的关系式分别为:logW=10.18-4.44logC,logW=11.98-4.79logC,logW=1.92-0.74logC.NaOH诱导体系聚集的能力大大高于NaCl和NaNO

    纹影测量成像系统及方法

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    一种纹影测量成像系统和方法,该系统包括光源,用于输出光信号;以及沿所述光源输出光信号路径依次设置的第一聚焦透镜、狭缝光阑、第一准直透镜、流场观测区域、第二聚焦透镜、刀口、第二准直透镜、数字微阵列反射镜、汇聚透镜和单点光电探测器;压缩算法模块,其与单点光电探测器电信号连接,用于重构图像,通过对图像的纹影计算方法计算出观测流场的结构分布。本发明将压缩感知理论与纹影测量相结合,创造性的提出稀疏纹影测量方法,具有高通量、高信噪比、快速灵活的特点,适宜于常规光强、弱光、微弱光、超微弱光和单光子纹影测量方式,是一种大动态范围的稀疏纹影测量方法
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