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GDI发动机活塞的停止过程特性

北京工业大学学报 2014年第9期40卷 1389-1393页

作者：李学军韩立伟马玉静吉林大学汽车动态模拟国家重点实验室长春130025 长春大学电子信息工程学院长春130022 长城汽车股份有限公司河北保定071000

基于发动机动力学理论,建立发动机停止过程中活塞的动力学模型,推导出停油熄火后缸内气体力矩以及曲轴输出力矩的计算公式.以三菱公司的4G15GDI发动机为例进行了仿真计算和台架实验,详细分析了发动机停止过程的缸内气体力矩和曲轴输出... 详细信息

基于发动机动力学理论,建立发动机停止过程中活塞的动力学模型,推导出停油熄火后缸内气体力矩以及曲轴输出力矩的计算公式.以三菱公司的4G15GDI发动机为例进行了仿真计算和台架实验,详细分析了发动机停止过程的缸内气体力矩和曲轴输出力矩特性、曲轴速度特性及活塞停止位置概率分布.仿真和实验结果显示：停机过程的缸内气体力矩和曲轴输出力矩变化过程是周期衰减过程,经过1.28 s转速由2000 r/s降至0 r/s.活塞自由停止位置约90%分布在上止点前60°~80°CA.

关键词：停机过程缸内直喷发动机力矩特性活塞位置

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进气温度对甲醇均质压燃燃烧特性的影响

吉林大学学报（工学版） 2009年第1期39卷 17-20页

作者：韩立伟洪伟张纪鹏郭英男常国锋吉林大学汽车工程学院长春130022

在一台快速压缩机上模拟甲醇HCCI的燃烧过程,通过缸压曲线和活塞位移曲线等数据进行计算分析,研究了进气温度对甲醇均质压燃燃烧特性的影响规律。结果表明,当其他边界条件一定时,随着甲醇混合气进气温度的增加,甲醇HCCI的燃烧始点提前,... 详细信息

在一台快速压缩机上模拟甲醇HCCI的燃烧过程,通过缸压曲线和活塞位移曲线等数据进行计算分析,研究了进气温度对甲醇均质压燃燃烧特性的影响规律。结果表明,当其他边界条件一定时,随着甲醇混合气进气温度的增加,甲醇HCCI的燃烧始点提前,缸内压力升高率峰值增加,放热率峰值增加,燃烧持续期缩短。

关键词：动力机械工程甲醇均质充气压缩点燃燃烧特性进气温度快速压缩机

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

Synergistic promotion strategy of “dual-site” and “dual-path” to enhance the C–C coupling between CO2 and HCHO driven by photoelectrocatalysis

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Journal of Energy Chemistry 2025年第1期100卷 39-49页

作者： Hongqiang Yang Jianfeng Zheng Guoyu Wang Yifei Gao Yatao Yang Jia li Xiaojin han Yan Cui Zhanggen Huang National Key Laboratory of High Efficiency and Low Carbon Utilization of Coal Institute of Coal Chemistry Chinese Academy of Science University of Chinese Academy of Science Shenyang University of Chemical Technology

Photoelectrocatalytic coupling CO2and volatile organic compounds （VOCs） is a promising green strategy for the synergistic conversion of the two carbon-containing resources to *** catalytic efficiency is always at the mercy of chemical inertness of CO2and the competitive hydrogen evolution of ***,a modified g-C3N4/ZnAl-LDH Z-scheme heterojunction catalyst with dual reaction site was rationally designed and precisely *** Faraday efficiency of ethanol reached 68.67%with a corresponding formation rate of 227.3μmol *** revealed by in-situ characterizations and density functional theory calculations,CO2and HCHO were absorbed at Zn site and N site,***,*CO generated from CO2and HCHO was converted to*CH3O and*CHO on the dual-active-site *** detailed reaction mechanism experiments indicated that C–C coupling only occurred between*CO and*CH3O in electrocatalysis *** from the“*CO+*CH3O”path,another“*CO+*CHO”coupling path was also detected in photoelectrocatalytic *** selectivity of ethanol was significantly enhanced due to the synthesis of dual-site catalyst and the dual-path coupling path between CO2and HCHO simultaneously driven by light and electricity.

关键词： Photoelectrocatalysis Z-scheme C–C coupling Ethanol

1986—2018年国家自然科学基金民族医药领域资助情况分析

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中国中药杂志 2019年第13期44卷 2886-2892页

作者：朱田田刘学伟韩立炜张凤珠甘肃中医药大学甘肃兰州730000 齐齐哈尔医学院黑龙江齐齐哈尔161006 国家自然科学基金委员会医学科学部北京100085

该文对1986—2018年国家自然科学基金民族医学、民族药学相关研究的申请和资助情况进行总结;对蒙古族、维吾尔族、藏族、壮族、苗族等民族医药领域资助项目的类别、数量与经费、主要研究内容等进行分析,旨在为民族医药项目的申报提供一... 详细信息

该文对1986—2018年国家自然科学基金民族医学、民族药学相关研究的申请和资助情况进行总结;对蒙古族、维吾尔族、藏族、壮族、苗族等民族医药领域资助项目的类别、数量与经费、主要研究内容等进行分析,旨在为民族医药项目的申报提供一定的参考。结果表明,民族医药项目的申请数量和资助数量的增长速度在2011年之后有显著提升,但其整体研究水平还有待进一步提高,且缺乏适合民族医药研究的特色与途径,尚需内地医学高等学府和科研机构给予更大的关注,共同推动民族医药领域基础研究的发展。

关键词：国家自然科学基金民族医学民族药学资助项目

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石墨烯-导电聚合物复合材料制备

化工新型材料 2016年第10期44卷 45-48页

作者：何亚萍韩权李伟李玺蔺倩西安文理学院化工学院西安710065

导电聚合物以其良好的生物兼容性,导电和非导电的可控的半导体性能,易于合成,好的氧化还原性质,宽的电化学活性范围和高的稳定性在传感器研究领域备受关注。石墨烯(GE)具有优良的光电磁性能,将其与导电聚合物复合有望改善其原有性能。... 详细信息

导电聚合物以其良好的生物兼容性,导电和非导电的可控的半导体性能,易于合成,好的氧化还原性质,宽的电化学活性范围和高的稳定性在传感器研究领域备受关注。石墨烯(GE)具有优良的光电磁性能,将其与导电聚合物复合有望改善其原有性能。采用电化学方法,分别利用方法选择和参数选择制备出石墨烯/聚苯胺(GE/PANI)复合材料,并对其电化学性能进行了研究。实验结果表明,复合材料中PANI能够较均匀的分散在GE片层上,且颗粒大小均匀。

关键词：电化学导电聚合物石墨烯聚苯胺

护肝片中五味子含量测定方法的建立及不同厂家产品含量的比较

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北京中医药大学学报 2011年第4期34卷 258-262页

作者：朱翔韩立炜马伟辰倪健吴清北京中医药大学中药学院北京100102 山东省淄博职业学院药学系

目的建立护肝片中4种木脂素类有效成分的含量测定方法,并采用新方法比较不同厂家产品含量的差异。方法采用RP-HPLC法,色谱柱：Hypersil C18柱（250 mm×4.6 mm,5μm）;流动相：乙腈-水系统梯度洗脱;检测波长：250 nm;流速：1mL/min;进样... 详细信息

目的建立护肝片中4种木脂素类有效成分的含量测定方法,并采用新方法比较不同厂家产品含量的差异。方法采用RP-HPLC法,色谱柱：Hypersil C18柱（250 mm×4.6 mm,5μm）;流动相：乙腈-水系统梯度洗脱;检测波长：250 nm;流速：1mL/min;进样量10μL。结果五味子醇甲、五味子酯甲、五味子甲素、五味子乙素的平均回收率依次为98.06%、98.28%、97.49%、99.82%,RSD依次为0.83%、1.80%、1.11%、0.83%。所收集的各厂家护肝片每片中五味子醇甲、五味子酯甲、五味子甲素、五味子乙素的含量依次为0.2128~0.6151 mg、0.0047~0.140 6 mg、0.0516~0.3050 mg、0.0913~0.3460 mg。结论本方法准确简便可行,可用于护肝片中五味子多指标成分的含量测定,且新方法测得不同厂家的产品质量差异显著。

关键词：护肝片高效液相色谱法含量测定五味子醇甲五味子酯甲五味子甲素五味子乙素

遵义市中小型水利工程移民实物调查细则编制探析

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水利建设与管理 2017年第5期37卷 50-53页

作者：韩曦李伟遵义水利水电勘测设计研究院贵州遵义563000 西北农林科技大学陕西杨凌712100

移民实物调查是编制中小型水利工程征地移民规划、论证移民补偿策略措施和实施移民征地的核心基础,也是工程规模确定、设计方案比选等工作开展的重要依据。根据水利水电工程建设征地补偿和移民安置条例要求,结合建设征地移民工作中常见... 详细信息

移民实物调查是编制中小型水利工程征地移民规划、论证移民补偿策略措施和实施移民征地的核心基础,也是工程规模确定、设计方案比选等工作开展的重要依据。根据水利水电工程建设征地补偿和移民安置条例要求,结合建设征地移民工作中常见的歧义和矛盾,从建设征地范围、农村部分和专业项目调查内容、社会经济调查内容、调查组织及程序和调查成果提交等方面,对遵义市中小型水利工程移民实物调查细则编制要求进行详细的论述,确保移民安置相关问题得到有效解决。

关键词：中小型水利工程建设征地移民实物调查

Potential role and therapeutic implications of glutathione peroxidase 4 in the treatment of Alzheimer's disease

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Neural Regeneration Research 2025年第3期20卷 613-631页

作者： Yanxin Shen Guimei Zhang Chunxiao wei Panpan Zhao Yongchun Wang Mingxi li li Sun Department of Neurology and Neuroscience Center The First Hospital of Jilin UniversityJilin UniversityChangchunJilin ProvinceChina Cognitive Impairment Center Department of NeurologyThe First Hospital of Jilin UniversityJilin UniversityChangchunJilin ProvinceChina

Alzheimer's disease is an age-related neurodegenerative disorder with a complex and incompletely understood pathogenesis. Despite extensive research, a cure for Alzheimer's disease has not yet been found. Oxidative stress mediates excessive oxidative responses, and its involvement in Alzheimer's disease pathogenesis as a primary or secondary pathological event is widely accepted. As a member of the selenium-containing antioxidant enzyme family, glutathione peroxidase 4 reduces esterified phospholipid hydroperoxides to maintain cellular redox homeostasis. With the discovery of ferroptosis, the central role of glutathione peroxidase 4 in anti-lipid peroxidation in several diseases, including Alzheimer's disease, has received widespread attention. Increasing evidence suggests that glutathione peroxidase 4 expression is inhibited in the Alzheimer's disease brain, resulting in oxidative stress, inflammation, ferroptosis, and apoptosis, which are closely associated with pathological damage in Alzheimer's disease. Several therapeutic approaches, such as small molecule drugs, natural plant products, and non-pharmacological treatments, ameliorate pathological damage and cognitive function in Alzheimer's disease by promoting glutathione peroxidase 4 expression and enhancing glutathione peroxidase 4 activity. Therefore, glutathione peroxidase 4 upregulation may be a promising strategy for the treatment of Alzheimer's disease. This review provides an overview of the gene structure, biological functions, and regulatory mechanisms of glutathione peroxidase 4, a discussion on the important role of glutathione peroxidase 4 in pathological events closely related to Alzheimer's disease, and a summary of the advances in small-molecule drugs, natural plant products, and non-pharmacological therapies targeting glutathione peroxidase 4 for the treatment of Alzheimer's disease. Most prior studies on this subject used animal models, and relevant clinical studies are lacking. Future clinica

关键词： apoptosis ferroptosis inflammation lipid peroxidation natural plant products neurodegenerative disorder neuroprotection oxidative stress small-molecule drugs