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新载体pET-DB对带有His-tag的仓鼠二氢叶酸还原酶的高效表达与纯化

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生物化学与生物物理进展 2004年第7期31卷 655-658页

作者：朱志勇谭波张文河张洪杰北京师范大学生物化学与分子生物学系北京100875 中国科学院生物物理研究所北京100101

报道了带有His tag的仓鼠二氢叶酸还原酶基因的克隆和在DB序列增强下T7启动子调控该基因在大肠杆菌中的可溶性高效表达 ,SDS PAGE分析表明 ,带有His tag的仓鼠二氢叶酸还原酶的含量可占大肠杆菌细胞总蛋白质含量的 4 6 % .该酶的纯化可... 详细信息

报道了带有His tag的仓鼠二氢叶酸还原酶基因的克隆和在DB序列增强下T7启动子调控该基因在大肠杆菌中的可溶性高效表达 ,SDS PAGE分析表明 ,带有His tag的仓鼠二氢叶酸还原酶的含量可占大肠杆菌细胞总蛋白质含量的 4 6 % .该酶的纯化可用常规的金属络合树脂一步纯化至SDS PAGE一条带 ,经凝血酶切去His tag的仓鼠二氢叶酸还原酶与用等电聚焦法获得的无His tag的酶有相同的酶活性 .

关键词：蛋白质表达二氢叶酸还原酶 pET—DB载体 His—tag

Cloud Computing:A Synthesis Models for Resource Service Management

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Cloud Computing:A Synthesis Models for Resource Service Mana...

Triboelectric nanogenerator integrated with a simple controlled switch for regularized water wave energy harvesting

2010 Second International Conference on Communication Systems, Networks and Applications (ICCSNA 2010)

作者： Mengkun Li Department of Computer science and technology china university of Petroleum (beijing) beijing china Ming Chen Department of Computer science and technology china university of Petroleum (beijing) beijing china Jun Xie College of Information Engineering Capital normal university beijing 100048 china

A computational is a wide-area computing environment for cross-domain resource sharing and service *** clouds generally emphasize sharing resources and services on demand,the scheduling strategy based on selecting resource that are near and owns more bandwidth available has better *** notion of game theory is proposed in this paper,which can be used as the criteria for cloud selection taking physical distance,bandwidth available and cost into consideration,combine the performance optimization and the price optimization to implement scheduling optimization in a whole sense so as to improve the stability and effectiveness of clouds resource scheduling.A synthesis-based Resource Allocation for Clouds framework is described.A modeling is developed to enable performance of the algorithm to be investigated quantitatively.

关键词： Cloud Resource Service Synthesis Scheduling

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Nano Research 2024年第8期17卷 7585-7592页

作者： hongbo Yang Xi Liang Junwu Kan Zhong Lin Wang Tao Jiang Zhanyong hong College of Engineering Zhejiang Normal UniversityJinhua 321004China beijing Key Laboratory of Micro-Nano Energy and Sensor Center for High-Entropy Energy and SystemsBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing 101400China The beijing Key Laboratory for Nano-Photonics and Nano-Structure Department of PhysicsCapital Normal UniversityBeijing 100048China Guangzhou Institute of Blue Energy Guangzhou 510555China Georgia Institute of Technology AtlantaGA 30332-0245USA Yonsei Frontier Lab Yonsei UniversitySeoul 03722Republic of Korea

Ocean is full of low-frequency,irregular,and widely distributed wave energy,which is suitable as the energy source for maritime Internet of Things(IoTs).Utilizing triboelectric nanogenerators(TENGs)to harvest ocean wave energy and power sensors is proven to be an effective ***,in random ocean waves,the irregular electrical energy output by general TENGs restricts the *** present,achieving regularized water wave energy harvesting relies on rather complex mechanical structure designs,which is not conducive to *** this work,we proposed a novel mechanical controlled TENG(MCTENG)with a simple controlled switch to realize the regularization *** structural parameters of the MC-TENG are optimized,and the optimal output voltage,output current,and transferred charge respectively reach 1684.2 V,85.4μA,and 389.9 nC,generating a peak power density of 38.46 W·m^(−3)·Hz^(−1).Under real water wave environment,the output of the MC-TENG is regularized and keeps stable regardless of any wave ***,the potential applications of the MC-TENG are demonstrated in powering environmental temperature,humidity,and wind speed *** work renders a simple approach to achieve effective regularized ocean wave energy harvesting,promoting the TENG industrialization toward practical application of maritime IoTs.

关键词： water wave energy harvesting triboelectric nanogenerators random excitation mechanical control regular output

Control of facies and fluid potential on hydrocarbon accumulation and prediction of favorable Silurian targets in the Tazhong Uplift,Tarim Basin,china

维普期刊数据库评论

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Petroleum Science 2011年第1期8卷 24-33页

作者： Yu Yixing Chen Dongxia Pang hong Shi Xiuping Pang Xiongqi State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing 102249China

Exploration practices show that the Silurian hydrocarbon accumulation in the Tazhong Uplift is extremely *** research indicates that the oil and gas accumulation is controlled by favorable facies and low fluid *** the macro level,hydrocarbon distribution in this uplift is controlled by structural zones and sedimentary *** the micro level,oil occurrences are dominated by lithofacies and petrophysical *** control of facies is embodied in high porosity and permeability controlling hydrocarbon ***,the macro oil and gas distribution in the uplift is also influenced by the relatively low fluid potential at local highs,where most successful wells are *** wells are also closely related to the adjacent ***,the Silurian hydrocarbon accumulation mechanism in the Tazhong Uplift can be described as *** by structures,the deep and overpressured fluids migrated through faults into the sand bodies with relatively low potential and high porosity and *** released overpressure expelled the oil and gas into the normal-pressured zones,and the hydrocarbon was preserved by the overlying caprock of poorly compacted Carboniferous and Permian *** a mechanism reflects favorable facies and low potential controlling hydrocarbon *** on the statistical analysis of the reservoirs and commercial wells in the uplift,a relationship between oil-bearing property in traps and the facies-potential index was established,and a prediction of two favorable targets was made.

关键词： Tazhong Uplift Silurian control of facies fluid potential oil and gas prediction

学习焦虑、学习态度和投入动机与学业成绩关系的研究——关于《心理统计学》学习经验的调查

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心理发展与教育 2005年第1期21卷 55-59,86页

作者：王爱平车宏生北京师范大学心理学院北京100875

本研究对122名本科生《心理统计学》课程的学习经验进行调查,其结果为:(1)在该课程的学习经验和考试成绩上男、女生差异显著,它表现在学习态度层面的有用性和成就态度,投入动机层面的自我投入上女生均优于男生;研究还发现,考分低则焦虑... 详细信息

本研究对122名本科生《心理统计学》课程的学习经验进行调查,其结果为:(1)在该课程的学习经验和考试成绩上男、女生差异显著,它表现在学习态度层面的有用性和成就态度,投入动机层面的自我投入上女生均优于男生;研究还发现,考分低则焦虑水平较高;(2)学习焦虑、学习态度、投入动机与考试成绩之间有显著相关,其中学习焦虑与成绩呈负相关,学习态度、投入动机与成绩呈正相关;(3)学习焦虑,学习态度和投入动机均影响学习成绩。学习成绩不仅受到学习焦虑和投入动机的直接影响,还受到学习态度等因素的间接影响。

关键词：学习态度学习焦虑学习经验动机学习成绩考试成绩女生调查统计学心理

Detecting short-term gravitational waves from post-merger hyper-massive neutron stars with a kilohertz detector

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Chinese Physics B 2024年第8期33卷 222-228页

作者：陈奕康朱宗宏 Institute for Frontier in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Department of Astronomy Beijing Normal UniversityBeijing 100875China

Gravitational waves emanating from binary neutron star inspirals,alongside electromagnetic transients resulting from the aftermath of the GW170817 merger,have been successfully ***,the intricate post-merger dynamics that bridge these two sets of observables remain *** includes if,and when,the post-merger remnant star collapses to a black hole,and what are the necessary conditions to power a short gamma-ray burst,and other observed electromagnetic *** focus is on the detection of gravitational wave(GW)emissions from hyper-massive neutron stars(NSs)formed through binary neutron star(BNS)*** several kilohertz GW detectors,we simulate BNS mergers within the detection limits of LIGO-Virgo-KARGA *** objective is to ascertain the fraction of simulated sources that may emit detectable post-merger GW *** kilohertz detectors equipped with a new cavity design,we estimate that approximately 1.1%-32%of sources would emit a detectable post-merger GW *** fraction is contingent on the mass converted into gravitational wave energy,ranging from 0.01M_(sun)to 0.1M_(sun).Furthermore,by evaluating other well-regarded proposed kilohertz GW detectors,we anticipate that the fraction can increase to as much as 2.1%-61%under optimal performance conditions.

关键词： neutron star mergers gravitational waves

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中介效应检验程序及其应用

心理学报 2004年第5期36卷 614-620页

作者：温忠麟张雷侯杰泰刘红云华南师范大学教育科学学院广州510631 香港中文大学教育学院香港北京师范大学心理学院北京100875

讨论了中介变量以及相关概念、中介效应的估计;比较了检验中介效应的主要方法;提出了一个检验程序,它包含了依次检验和Sobel检验.该程序检验的第一类和第二类错误率之和通常比单一检验方法小,既可以做部分中介检验,也可以做完全中介检验... 详细信息

讨论了中介变量以及相关概念、中介效应的估计;比较了检验中介效应的主要方法;提出了一个检验程序,它包含了依次检验和Sobel检验.该程序检验的第一类和第二类错误率之和通常比单一检验方法小,既可以做部分中介检验,也可以做完全中介检验.作为示范例子,引入中介变量研究学生行为对同伴关系的影响.

关键词：中介变量检验第一类错误率功效同伴关系

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新西兰教育服务贸易研究

外国教育研究 2006年第4期33卷 15-19页

作者：洪成文张薇薇赵应生北京师范大学教育管理学院北京100875

教育服务贸易是当下国际教育领域中备受关注的话题,而新西兰教育服务贸易在最近十年的发展尤其迅速。文章主要介绍新西兰发展教育服务贸易的背景、教育服务贸易发展的现状,并在此基础上总结其经验与得失,以便学者们关注教育服务贸易的... 详细信息

教育服务贸易是当下国际教育领域中备受关注的话题,而新西兰教育服务贸易在最近十年的发展尤其迅速。文章主要介绍新西兰发展教育服务贸易的背景、教育服务贸易发展的现状,并在此基础上总结其经验与得失,以便学者们关注教育服务贸易的比较研究。

关键词：新西兰教育服务贸易世界贸易组织

The Role of Family Migration in Child Development:A Propensity Score Matching Analysis Based on Migrant and Non-Migrant Infants and Young Children

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Frontiers of Education in china 2024年第2期19卷 138-151页

作者： hong Xiumin LIU Qianqian ZHANG Mingzhu Faculty of Education Beijing Normal UniversityBeijing 100875China Shandong Province Pre-Primary School Center Jinan 250012China

Based on the survey data of 4,739 infants and young children(IYC)under 3 years old,the study uses the propensity score matching(PSM)method to examine the role of family migration in infant and young child development(IYCD).The study finds that the development of migrant IYC is significantly behind that of non-migrant IYC in the real-world *** controlling for confounders at the individual and family levels,there is no significant statistical difference in early development between migrant IYC and non-migrant ***,family migration does not play a significant role in IYCD in different subgroups after *** protect the rights of migrant families and IYC in accessing public services,the Chinese government should build a social security policy system for migrant families and ensure starting point fairness for migrant IYC.

关键词： migrant families infants and young children(IYC) early development propensity score matching(PSM)