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Application of convolution perfectly matched layer in finite element method calculation for 2D acoustic wave

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Chinese Journal of Acoustics 2012年第1期31卷 18-28页

作者： li Yifeng liN Zhiqi li guofeng WANG Yun College of Electronics and Information Engineering NanJing Univ. of Technology NanJing 210009 College of Electrical and Electronic Engineering ChangChun Univ. of Technology ChangChun 130012） Institute of Phys. and Electronics and Info. Engineering LangFang Teachers College LangFang 065000 Institute of Mathematics and Information Sciences LangFang Teachers College LangFang 065000

A method was presented to extend the Convolution Perfectly Matched Layer （CPML）, which bases on the complex coordinates transformation and complex frequency shifted stretched- coordinate metrics, to the 2D acoustic equation calculated with the method of Finite Element Method （FEM）. This non-physical layer is used at the computational edge of a FEM as an Ab- sorbing Boundary Condition （ABC） to truncate unbounded media. In this paper, the CPML equations have been presented in frequency domain and in time domain, respectively, and the calculations have been realized in the FEM software of COMSOL. The main advantage of CPML over the classical PML layer is that it is based on the unsplit components of the wave field leading to a more stable, highly effective absorption and a more facility to realize. The results of numerical simulation demonstrate that CPML has better absorbability than PML and it absorbs the out^oin~ energy more effectivelv.

关键词：卷积完全匹配层有限元计算声波方程有限元方法二维有限元分析软件应用高效吸收

Sedimentary systems of the Oligocene Huagang Formation in the central anticline zone of the Xihu Depression,East China Sea Shelf Basin

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Energy Geoscience 2024年第1期5卷 275-282页

作者： Wenbo Zheng guofeng Yin li Sun Shuijian Wei Xiuping Wei Bo Niu Petroleum Exploration and Production Research Institute of SINOPEC Beijing100083China Shanghai Offshore Oil&Gas Branch SINOPECShanghai200120China

The Xihu Depression is the largest hydrocarbon-bearing depression of the East China Sea Shelf Basin(also referred to as the ECSSB).However,the depositional systems and reservoir distribution of the Oligocene Huagang Formation in the Xihu Depression are still *** the guidance of sedimentology and stratigraphy,this study documented a marine-terrestrial transitional environment in the restricted bay setting of the Oligocene Huagang Formation through core description,well logging,and seismic data *** study also revealed that the Oligocene Huagang Formation is dominated by tidal delta,estuary,and gravity flow deposits in the central anticline zone of the Xihu *** new understanding of the sedimentary systems and the discovery of the transgressive gap in the eastern Diaoyu Islands uplift explain the origin of fine-grained sediments and the EW-trending sand bodies in the central depression and the sand bodies parallel to shoreline in the west slope belt,which cannot be explained by previous study results,such as southern transgression or fluvial deltas and even lacustrine ***,the tidal channels,tidal sand flats,and gravity flow sand bodies formed by the transgressive tides are high-quality *** study will provide a basis for well placement and serve as guidance for the selection of favorable hydrocarbon exploration areas in the Xihu Depression.

关键词： Estuary Sedimentary system Oligocene Huagang Formation Central anticline Xihu Depression East China Sea Shelf Basin

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2021年度新疆阿克苏地区细绒棉品质分析

中国棉花 2024年第2期51卷 33-37页

作者：王娟李国锋王永斌张小建甘莉莉王晓辉阿克苏地区纤维检验所新疆阿克苏843000 阿克苏职业技术学院新疆阿克苏843000

对2021年度(棉花年度,下同)的新疆阿克苏地区细绒棉仪器化公证检验数据进行统计,分析了细绒棉纤维颜色级、长度、马克隆值、断裂比强度、长度整齐度指数、轧工质量等主要指标,并比对了2019年度、2020年度、2021年度各指标变化趋势,以真... 详细信息

对2021年度(棉花年度,下同)的新疆阿克苏地区细绒棉仪器化公证检验数据进行统计,分析了细绒棉纤维颜色级、长度、马克隆值、断裂比强度、长度整齐度指数、轧工质量等主要指标,并比对了2019年度、2020年度、2021年度各指标变化趋势,以真实反映阿克苏地区细绒棉品质状况。总体来看,2021年度阿克苏地区细绒棉长度、马克隆值B级以上占比较前2年有较大提升,颜色级白棉3级及以上细绒棉占比较前2年有所降低,断裂比强度指标高于2019年度、低于2020年度,长度整齐度指数及轧工质量变化不大。

关键词：阿克苏地区细绒棉纤维品质公证检验长度断裂比强度

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责任关怀理念融入高职院校化工专业人才培养模式的创新研究

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化工管理 2024年第20期 45-48页

作者：贾琪王明权李国峰杨伟强李帅迪力奴尔·库尔班江董静新疆应用职业技术学院新疆奎屯833299 南京科技职业学院江苏南京210048 中国石油独山子石化公司炼油一部新疆克拉玛依834000

文章从教师团队建设、教材体系、教学内容、教学方法、科普实践及平台构建等多个方面系统分析了责任关怀理念融入新疆高职院校化工专业人才培养模式的创新策略,旨在全面增强职业院校化工类师生的责任关怀意识和专业素养,推动化工企业践... 详细信息

文章从教师团队建设、教材体系、教学内容、教学方法、科普实践及平台构建等多个方面系统分析了责任关怀理念融入新疆高职院校化工专业人才培养模式的创新策略,旨在全面增强职业院校化工类师生的责任关怀意识和专业素养,推动化工企业践行责任关怀理念,为当地石油化工行业绿色、健康、安全可持续发展提供一定的保障。

关键词：新疆高职院校责任关怀化工专业人才培养教学改革

Convergent synthesis and immunological study of oligosaccharide derivatives related to galactomannan from Antrodia cinnamomea

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Chinese Chemical Letters 2024年第5期35卷 155-160页

作者： Shuying li Weiwei ZhuGe Xuan Sun Chongzhen Sun Zhaojun liu Chenghe Xiong Min Xiao guofeng Gu National Glycoengineering Research Center and Shandong Key Laboratory of Carbohydrate Chemistry and Glycobiology Shandong UniversityQingdao 266237China NMPA Key Laboratory for Quality Research and Evaluation of Carbohydrate-based Medicine Shandong UniversityQingdao 266237China

The galactomannan from Antrodia cinnamomea(AC)is characterized as one of the important bioactive components that exhibits potential immunostimulatory *** biological function of its corresponding oligosaccharide fragments has not been revealed *** this study,we reported the first chemical synthesis of the series of oligosaccharide fragments related to AC galactomannan via the convergent glycosylation *** preliminary immunological evaluation of these synthesized AC oligosaccharides disclosed that the backbone tetrasaccharide 1d showed the best immunomodulatory ability on enhancing proliferation,phagocytosis and cytokines secretion of Raw264.7 macrophages in vitro,indicating its immense potential as an immunostimulant candidate.

关键词： Antrodia cinnamomea Galactomannan Oligosaccharide Immunostimulatory propriety Chemical synthesis

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软岩及土质隧洞围岩稳定性评价新方法

岩石力学与工程学报 2014年第9期33卷 1812-1821页

作者：李宁刘乃飞李国峰西安理工大学岩土工程研究所陕西西安710048 中国科学院寒区旱区环境与工程研究所冻土工程国家重点实验室甘肃兰州730000

首先提出对于软岩(土质)隧洞及时支护下的围岩变形稳定性可转化为支护结构的安全性这一评判理念,在此基础上进一步将初期支护(喷层)不出现拉压破坏时围岩与支护结构的对应变形作为评判标准,提出软质隧洞围岩稳定性评判新思路;考虑到支... 详细信息

首先提出对于软岩(土质)隧洞及时支护下的围岩变形稳定性可转化为支护结构的安全性这一评判理念,在此基础上进一步将初期支护(喷层)不出现拉压破坏时围岩与支护结构的对应变形作为评判标准,提出软质隧洞围岩稳定性评判新思路;考虑到支护结构内力的监测不便、不准,而支护结构的收敛变形监测较为方便与可靠这一工程现实,再次通过数值试验的方法,将支护结构的极限应力科学地转化为对应的支护结构的允许变形,进而建立能够考虑初期支护安全性的围岩稳定性评价新方法。该评判方法在新疆库尉输水隧洞工程的成功应用表明其具有较好的可靠性和适用性。

关键词：岩石力学软岩隧洞及时支护混凝土喷层应力稳定性评价

Interfacial molecular screening of polyimide dielectric towards high-performance organic field-effect transistors

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Chinese Chemical Letters 2024年第2期35卷 268-271页

作者： Yingshuang Zheng Huchao li Ting Jiang Fei Jiao Jie li Yong Lei guofeng Tian Jinshun Bi Yundong Xuan liqiang li Deyang Ji Wenping Hu Department of Chemistry Tianjin Key Laboratory of Molecular Optoelectronic SciencesInstitute of Molecular Aggregation ScienceTianjin UniversityTianjin 300072China GPL Photonics Laboratory State Key Laboratory of Applied OpticsChangchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Department of Chemistry Tianjin Key Laboratory of Molecular Optoelectronic SciencesSchool of ScienceCollaborative Innovation Center of Chemical Science and EngineeringTianjin UniversityTianjin 300072China Joint School of National University of Singapore and Tianjin University Fuzhou 350207China Fachgebiet Angewandte Nanophysik Institut für Physik & IMN MacroNanoTechnische Universität IlmenauIlmenau 98693Germany State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China Institute of Microelectronics Chinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100101China

The compatibility of the gate dielectrics with semiconductors is vital for constructing efficient conducting channel for high charge ***,it is still a highly challenging mission to clearly clarify the relationship between the dielectric layers and the chemical structure of semiconductors,especially vacuum-deposited small ***,interfacial molecular screening of polyimide(Kapton)dielectric in organic field-effect transistors(OFETs)is comprehensively *** is found that the semiconducting small molecules with alkyl side chains prefer to form a high-quality charge transport layer on polyimide(PI)dielectrics compared with the molecules without alkyl side *** this basis,the fabricated transistors could reach the mobility of 1.2 cm^(2) V^(−1)s^(−1) the molecule with alkyl side chains on bare PI *** is more,the compatible semiconductor and dielectric would further produce a low activation energy(E_(A))of 3.01 meV towards efficient charge transport even at low temperature(e.g.,100 K,0.9 cm^(2) V^(−1)s^(−1)).Our research provides a guiding scheme for the construction of high-performance thin-film field-effect transistors based on PI dielectric layer at room and low temperatures.

关键词： Interfacial molecular screening Polyimide dielectrics Organic semiconductors Interface engineering Thin-film transistors

青海高原地区中老年人多维度认知功能及影响因素的性别差异分析

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中国神经免疫学和神经病学杂志 2024年第1期31卷 25-33页

作者：刘文增赵婷婷侯永兰张桂娟钟欣李国峰李鹤张占军朱爱琴青海省人民医院老年医学科 810007 河南省漯河市中心医院 462300 青海大学研究生院 810000 中国中医科学院中医临床基础医学研究所 100700 北京师范大学老年脑健康研究中心 100875

目的探讨高原地区中老年人多维度认知功能的性别差异,以及不同性别中老年人发生轻度认知功能障碍(mild cognitive impairment, MCI)的影响因素。方法采用横断面随机抽样调查方法,选取青海地区(平均海拔3 000 m)中老年人500名(男性299... 详细信息

目的探讨高原地区中老年人多维度认知功能的性别差异,以及不同性别中老年人发生轻度认知功能障碍(mild cognitive impairment, MCI)的影响因素。方法采用横断面随机抽样调查方法,选取青海地区(平均海拔3 000 m)中老年人500名(男性299名、女性201名)。收集被调查者人口学信息、慢性病史、运动、经济和婚姻状况以及外周血指标,并进行多维度认知功能和心理评估,包括简易智能状态量表(mini mental state examination, MMSE)筛查、Rey-Osterrieth复杂图形测验-延迟回忆(complex figure test delay recall, CFT-DR)、连线测验A和B(trail making test, TMT-A&B)和数字符号转换测验(symbol-digit modalities test, SDMT)等,采用协方差分析不同性别人群年龄和教育程度对认知功能的影响。应用Logistic回归分析MCI发生的影响因素。结果与女性比较,男性总体认知、情景记忆、工作记忆评分均增高(P<0.05和P<0.01),但注意力和执行力以及睡眠质量和抑郁状态评分明显降低(P<0.01)。校正受教育程度和年龄后,男性在不同年龄组和受教育程度组中总体认知、情景记忆、注意力和执行力均优于女性(P<0.05,P<0.01)。进一步对比发现女性MCI患病率高于男性(25.9%比19.4%;χ^(2)=4.461,P<0.05)。Logistic回归分析显示,高龄(OR男80岁~=3.636,OR女70岁~=2.578,OR男70岁~=2.914,OR女80岁~=1.500)是中老年人群发生MCI的危险因素(P<0.05,P<0.01),受教育程度高(OR男初中=0.146,OR女初中=0.166,OR女高中=0.151)是中老年人群发生MCI的保护因素(P<0.01)。而未婚是男性发生MCI的危险因素(OR=1.855,P<0.05),睡眠质量差(OR=1.083,P<0.05)和高同型半胱氨酸血症(OR=1.081,P<0.05)是女性发生MCI的危险因素,教师职业是女性MCI的保护因素(OR=0.206,P<0.05)。结论高原地区不同性别中老年人群存在多维度认知域的减退,其影响因素不同,随着增龄和教育水平低的影响,女性认知功能下降趋势比男性明显。女性是MCI发生的高危人群,针对性别差异应采取不同的预防和延缓认知损伤的措施。

关键词：高原地区中老年人群多维度认知域轻度认知障碍性别差异

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巨厚煤层三软回采巷道恒阻让压互补支护研究

岩石力学与工程学报 2011年第8期30卷 1619-1626页

作者：张国锋于世波李国峰霍君英中国矿业大学力学与建筑工程学院北京100083 中国矿业大学深部岩土力学与地下工程国家重点实验室北京100083

针对沈阳清水煤矿第三系巨厚大地压软围岩煤层回采巷道开掘后支护失效严重、围岩大变形及4次返修无法稳定的现象,分析围岩塑性流变、非对称变形破坏、支护体与围岩大变形不协调等变形力学机制。提出采用恒阻大变形锚杆初次支护,在恒阻... 详细信息

针对沈阳清水煤矿第三系巨厚大地压软围岩煤层回采巷道开掘后支护失效严重、围岩大变形及4次返修无法稳定的现象,分析围岩塑性流变、非对称变形破坏、支护体与围岩大变形不协调等变形力学机制。提出采用恒阻大变形锚杆初次支护,在恒阻力作用下保护锚固体的承载力,通过恒阻锚杆的延伸多次释放变形能,将集中应力转移到深部,调动深部围岩承载能力,形成稳定的塑性承载圈;然后针对回采巷道变形特点采用顶板加强、两帮让压、底角加固的二次互补加强支护,形成适应三软巷道变形特征的围岩–支护协同承载体,将围岩变形速率控制在合理范围。基于该方法下提出的锚索+恒阻大变形锚杆+钢带+底角锚注联合支护设计,在该矿南二采区205工作面运输顺槽中使用后,顶板下沉降低75%,两帮收缩减小60%,底臌减小42%,巷道支护状况得到明显改善。实践证明,恒阻让压互补支护系统可有效控制三软巷道围岩稳定。

关键词：采矿工程三软大变形回采巷道恒阻大变形锚杆恒阻让压互补支护