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MT1M and MT1G promoter methylation as biomarkers for hepatocellular carcinoma

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World Journal of Gastroenterology 2014年第16期20卷 4723-4729页

作者： Xiang-Fen Ji Yu-chen Fan shuai Gao Yang Yang Jian-Jun Zhang Kai Wang Department of Hepatology Qilu Hospital of Shandong University Institute of Hepatology Shandong University

AIM: To investigate the potential of promoter methylation of two tumor suppressor genes (TSGs) as biomarkers for hepatocellular carcinoma (HCC).

关键词： MT1M MT1G Methylation Serum biomarker Hepatocellular carcinoma

Critical tectonic events and their geological controls on deep buried coalbed methane accumulation in Daning-Jixian Block, eastern Ordos Basin

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Frontiers of Earth Science 2023年第1期17卷 197-217页

作者： Taotao YAN Shan HE shuai ZHENG Yadong BAI Wei chen Yanjun MENG Shangwen JIN Huifang YAO Xiaobao JIA College of Mining Engineering Taiyuan University of TechnologyTaiyuan 030024China Coal Reservoir Laboratory of National Engineering Research Center of CBM Development&Utilization China University of GeosciencesBeijing 100083China Shanxi CBM Exploration and Development Branch PetroChina Huabei Oilfield CompanyChangzhi 046000China China Coal Geology Group Co. LtdBeijing 100083China Research Institute of Petroleum Exploration and Development-Northwest PetroChinaLanzhou 730000China Beijing Furuibao Energy Technology Company Beijing 100176China Shanxi Province 148 Ecological Geology Technology Co. LtdTaiyuan 030053China

Commercial exploration and development of deep buried coalbed methane (CBM) in Daning-Jixian Block, eastern margin of Ordos Basin, have rapidly increased in recent decades. Gas content, saturation and well productivity show significant heterogeneity in this area. To better understand the geological controlling mechanism on gas distribution heterogeneity, the burial history, hydrocarbon generation history and tectonic evolution history were studied by numerical simulation and experimental simulation, which could provide guidance for further development of CBM in this area. The burial history of coal reservoir can be classified into six stages, i.e., shallowly buried stage, deeply burial stage, uplifting stage, short-term tectonic subsidence stage, large-scale uplifting stage, sustaining uplifting and structural inversion stage. The organic matter in coal reservoir experienced twice hydrocarbon generation. Primary and secondary hydrocarbon generation processes were formed by the Early and Middle Triassic plutonic metamorphism and Early Cretaceous regional magmatic thermal metamorphism, respectively. Five critical tectonic events of the Indosinian, Yanshanian and Himalayan orogenies affect different stages of the CBM reservoir accumulation process. The Indosinian orogeny mainly controls the primary CBM generation. The Yanshanian Orogeny dominates the second gas generation and migration processes. The Himalayan orogeny mainly affects the gas dissipation process and current CBM distribution heterogeneity.

关键词： deep buried coalbed methane coal reservoir accumulation evolution numerical simulation Daning-Jixian Block

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硅碳负极的失效机理与FEC的改善作用

华南师范大学学报（自然科学版） 2024年第2期56卷 18-24页

作者：王海李素丽郭若愚黄玲玲黄浩南陈帅许梦清李伟善华南师范大学化学学院锂离子电池材料国家地方联合工程研究中心广州510006 珠海冠宇电池股份有限公司珠海519180

采用含和不含氟代碳酸乙烯酯(FEC)的电解液,研究了一种硅碳材料作为锂离子电池负极的充放电行为,对充放电循环前后的硅碳电极进行了组成和形貌的谱学表征,并通过计算比较了电解液主要成分的还原活性。结果表明:不含FEC的电解液,硅碳负... 详细信息

采用含和不含氟代碳酸乙烯酯(FEC)的电解液,研究了一种硅碳材料作为锂离子电池负极的充放电行为,对充放电循环前后的硅碳电极进行了组成和形貌的谱学表征,并通过计算比较了电解液主要成分的还原活性。结果表明:不含FEC的电解液,硅碳负极首次充放电库伦效率低、容量衰减快,这是因为硅碳表面不能形成稳定的SEI,嵌锂后体积膨胀使SEI开裂,电解液持续分解。相反,含FEC的电解液,因FEC比电解液其他组分更容易在硅碳负极上还原,生成含氟的聚合物,形成稳定的SEI,抑制电解液还原分解,并缓冲硅碳负极的体积膨胀,从而显著提高库伦效率和循环稳定性。添加5%的FEC,硅碳负极首次充放电库伦效率从83%提高到86%;添加10%的FEC,0.2 C充放电循环50次后,硅碳负极的容量保持率从28%提高到75%。

关键词：锂离子电池硅碳负极失效氟代碳酸乙烯酯

Experimental study on concrete box culverts in trenches

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Frontiers of Structural and Civil Engineering 2009年第1期3卷 73-80页

作者： Baoguo chen Junjie ZHENG jie HAN School of Civil Engineering and Mechanics Huazhong University of Science and TechnologyWuhan 430074China Engineering Faculty China University of GeosciencesWuhan 430074China Civil Environmentaland Architectural Engineering Departmentthe University of KansasKS 66045USA

Concrete box culverts are widely used in expressways in mountain *** problems frequently take place due to improperly estimated vertical earth pressures on *** prevailing Chinese General Code for Design of Highway Bridges and Culverts(CGCDHBC)stipulates the computation of the design load on culverts primarily based on the linear earth pressure theory,which cannot accurately describe the variation of the vertical load on culverts in *** this paper,a full-scale experiment and numerical simulation were conducted to evaluate the variation of vertical earth pressures on culvert and soil arching in *** variations of foundation pressure and settlement were also *** result revealed that the soil arch forms when the backfill on the culvert reaches a certain *** soil arching effect reduces the stress concentration on the crown of the culvert but it is *** vertical earth pressure on top of the culvert is significantly different from that recommended by the CGCDHBC.

关键词： culvert vertical earth pressure soil arch fullscale experiment numerical simulation

含蜡油气水合物生成特性及其浆液黏度影响因素

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中国海上油气 2024年第3期36卷 221-229页

作者：张自印庄乐泉曹波波罗泽利敬加强孙杰陈星宇中海石油(中国)有限公司深圳分公司广东深圳518000 西南石油大学石油与天然气工程学院四川成都610500 油气消防四川省重点实验室四川成都610500

蜡、水合物及其耦合沉积是海洋油气多相混输工艺潜在风险问题。以天然气、去离子水、3#工业白油和石蜡为实验介质,依托可视化高压反应釜,基于正交实验设计的方法,分别选用L9(34)和L16(45)正交表设计并开展了无蜡和含蜡2种体系下天然气... 详细信息

蜡、水合物及其耦合沉积是海洋油气多相混输工艺潜在风险问题。以天然气、去离子水、3#工业白油和石蜡为实验介质,依托可视化高压反应釜,基于正交实验设计的方法,分别选用L9(34)和L16(45)正交表设计并开展了无蜡和含蜡2种体系下天然气水合物生成实验;以流体当量黏度为评价指标,分析了含蜡量、搅拌速率、流体平衡温度、含水率、起始压力对水合物浆液当量黏度的影响显著程度。实验结果表明:黏度值恒定并不能判断反应釜中水合物生成是否结束,因为在剪切稳定阶段,脱离搅拌中心区域的水合物与搅拌区域新生成的水合物存在一种“动态平衡”状态;含蜡量越高,水合物生长诱导期越长;在含蜡量2%与3%水合物的快速生长阶段,扭矩与转速会发生2次突变,第1次突变原因是蜡晶的大量析出导致搅拌中心区域油相胶凝结构增强,第2次突变原因是水合物大量生成并与析出的蜡晶相互吸附形成了蜡-水合物聚集体,在离心作用下脱离了搅拌中心区域;各因素对于无蜡和含蜡体系水合物浆液当量黏度的影响显著程度相似,搅拌速率均为主要影响因素。研究结果对深水油气管道的安全运行具有重要的理论意义和实用价值。

关键词：蜡-水合物聚集体蜡晶当量黏度水合物正交实验影响因素

Review of High-Precision Sr Isotope Analyses of Low-Sr Geological Samples

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Journal of Earth Science 2015年第5期26卷 763-774页

作者： jie Lin Yongsheng Liu Haihong chen Lian Zhou Zhaochu Hu Shan Gao State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences

Isotope plays an important role in both tracing and dating in earth science, especially 87Rb-86 Sr system. With the development of earth science, whole-rock analysis can＇t sufficiently meet the requirements for scientific research and the micro-analysis becomes more and more significant. Laser ablation multi-collector inductively-coupled plasma mass-spectrometry（LA-MC-ICP-MS） has been extensively applied in micro-zone analysis due to its low sample-consumption, high accuracy, in situ and low requirements on matrix, but it is still difficult to accurately measure Sr isotope compositions especially for the samples with high Rb/Sr ratios and low Sr contents as it is restricted by severe quality discrimination and various types of mass spectrum interferences. Consequently, thermal ionization mass-spectrometry（TIMS）, as the most accurate and precise method to analyze isotopic ratios, is still the most popular method of analyzing Sr ratios, especially for the samples with low Sr contents. This paper makes a systematic review on the high-precision Sr isotope analyses of low-Sr geological samples, including the micro-sampling technique, ultra-low procedural blank chemical method and TIMS measurement technique. The combination of ultra-low procedural blank and TIMS can be used to perform high-precision micro-analysis of the samples with ng magnitude, which will be undoubtedly an important direction for Rb-Sr geochronology, geochemistry and environmental studies.

关键词： Sr isotope compositions Ultra-low procedural blank TIMS Micro-sampling Sr-specific resin Micro-ion exchange column

紫花苜蓿青贮饲料对草鱼生长性能和肌肉品质的影响

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草地学报 2024年第09期32卷 2990-2998页

作者：陈辰滑少波李杰勤姜华黄鹤平姜婉琦姚敏学李向飞初晓辉刘秦华南京农业大学蒙草生态环境(集团)股份有限公司安徽省饲草生物育种国际合作研究中心云南农业大学

为了更好地在渔业中利用青贮饲料，本试验研究了不同收获期紫花苜蓿(Medicago sativa L.)调制而成的青贮饲料在南京秋季对草鱼(Ctenopharyngodon idella)生长性能、肠道消化力和肉质等的影响。试验设对照组(CON组)、初花期(CH组)和盛花... 详细信息

为了更好地在渔业中利用青贮饲料，本试验研究了不同收获期紫花苜蓿(Medicago sativa L.)调制而成的青贮饲料在南京秋季对草鱼(Ctenopharyngodon idella)生长性能、肠道消化力和肉质等的影响。试验设对照组(CON组)、初花期(CH组)和盛花期(KH组)紫花苜蓿青贮饲料替代15%蛋白预混料。挑选150条初始体重为(1000±50) g的草鱼，随机分成三组，每组50条，饲喂60 d后取样分析。结果表明，与CON组相比，CH组和KH组对草鱼最终体重、质量增加率和特定生长率无显著影响，CH组草鱼肠道蛋白酶活性显著增加(P<0.05),KH组草鱼肠道蛋白酶活性显著降低(P<0.05);CH组和KH组草鱼肌肉质构指标均无显著差异；KH组谷草转氨酶和谷丙转氨酶显著高于CON组与CH组(P<0.05)。综上所述，初花期和盛花期紫花苜蓿青贮饲料替代15%蛋白预混料未影响秋季草鱼增重，呈现提高草鱼肉质的趋势，且初花期紫花苜蓿青贮饲料替代组提高了草鱼肠道蛋白酶活性。因此，初花期紫花苜蓿青贮饲料替代15%蛋白预混料饲养草鱼的潜力巨大。

关键词：紫花苜蓿青贮饲料草鱼消化酶肌肉品质

Design of a linear-rotary ultrasonic motor for optical focusing inspired by the bionic motion principles of the earthworms

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International Journal of Smart and Nano Materials 2022年第2期13卷 346-365页

作者： Yingzhi Wang jie Deng Shijing Zhang He Li Weishan chen Yingxiang Liu State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbinHeilongjiang ProvinceChina

Multi-motor configuration of multi-DOF(degree of freedom)optical system is a major source of redundant structure,putting a limitation on the simple and miniaturized ***,a novel two-DOF ultrasonic motor(USM)is proposed to provide a feasible method of application in the lens autofocus of the optical *** proposed USM operates by one longitudinal mode and two orthogonal bending modes,which is inspired by the bionic motion principle of the *** frequency degeneration among the three working modes is per-formed,and the working principle of the USM is verified via the FEM simulation.A prototype of the two-DOF USM is fabricated,and its mechanical output characteristics are *** experimental results indicate that the prototype achieves the maximum rotary and linear speeds of 3319.6 rpm and 57.6 mm/s,***,we demonstrate the result of a simple focusing experiment using the prototype and obtain a series of clear pictures,which verifies the feasibility of application in the optical focusing system.

关键词： Ultrasonic motor bondedtype two-DOF motions optical focusing bionic motion

Verification of workflow nets with transition conditions

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第7期13卷 483-509页

作者： Zhao-xia WANG Jian-min WANG Xiao-chen ZHU Li-jie WEN School of Software Tsinghua UniversityBeijing 100084China Department of Computer Science and Technology Tsinghua UniversityBeijing 100084China MOE Key Laboratory for Information System Security Tsinghua UniversityBeijing 100084China National Laboratory for Information Science and Technology Tsinghua UniversityBeijing 100084China SDepartment of Logistical Information&Engineering Logistical Engineering UniversityChongqing 400016China

Workflow management is concerned with automated support for business *** management systems are driven by process models specifying the tasks that need to be executed,the order in which they can be executed,which resources are authorised to perform which tasks,and data that is required for,and produced by,these *** workflow instances may run over a sustained period of time,it is important that workflow specifications be checked before they are *** verification is usually concerned with control-flow dependencies only;however,transition conditions based on data may further restrict possible choices between *** this paper we extend workflow nets where transitions have concrete conditions associated with them,called *** then demonstrate that we can determine which execution paths of a WTC-net that are possible according to the control-flow dependencies,are actually possible when considering the conditions based on ***,we are able to more accurately determine at design time whether a workflow net with transition conditions is sound.

关键词： Workflow nets Transition condition Verification Process model