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巴氏芽孢八叠球菌及相关微生物的生物矿化的分子机理与应用

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中国生物工程杂志 2017年第8期37卷 96-103页

作者：吴洋练继建闫玥齐浩天津大学化工学院天津300072 系统生物工程教育部重点实验室天津300072 天津大学化工协同创新中心合成生物学平台天津300072 天津大学前沿技术研究院天津300072 天津大学水利工程仿真与安全国家重点实验室天津300072

巴氏芽孢八叠球菌是迄今为止所知的利用尿素降解进行生物矿化的最为高效的微生物系统之一,基于其碳酸钙生物矿化形成的"超强能力",巴氏芽孢八叠球菌已经被成功地应用于沙石、土壤等生物固化中,成为一种全新的、具有极大潜力的生物建筑... 详细信息

巴氏芽孢八叠球菌是迄今为止所知的利用尿素降解进行生物矿化的最为高效的微生物系统之一,基于其碳酸钙生物矿化形成的"超强能力",巴氏芽孢八叠球菌已经被成功地应用于沙石、土壤等生物固化中,成为一种全新的、具有极大潜力的生物建筑辅助技术,被称为"生物水泥"。由于巴氏芽孢八叠球菌分离自土壤,没有病原性并具有极好的环境友好性。近年来,其应用领域被拓展到环境治理乃至健康医疗领域,成为全新的研究热点。然而,与应用研究相比,人们对巴氏芽孢八叠球菌生物矿化背后的分子机理还知之甚少。因此,这里针对迄今为止国内外对于巴氏芽孢八叠球菌生物矿化相关的分子机理的研究进行分析介绍,在此基础上综述了包括建工、环境、及医疗健康领域在内的巴氏芽孢八叠球菌的应用,希望能够促进对于该球菌矿化的研究。

关键词：生物矿化巴氏芽孢八叠球菌脲酶

A micro-crosslinked amphoteric hydrophobic association copolymer as high temperature-and salt-resistance fluid loss reducer for water-based drilling fluids

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Petroleum Science 2024年第3期21卷 1980-1991页

作者： jian Li Yu-Xi ji Xiao-Xiao Ni Kai-He Lv Xian-Bin Huang jin-Sheng Sun School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Key Laboratory of Unconventional Oil&Gas Development China University of Petroleum(East China)Qingdao26650ShandongChina Inspection and Testing Center of Huabei Oil Field Company PetroChinaRenqiu062552HebeiChina Drilling Fluid Research Institute CNPC Engineering Technology R&D Company LimitedBeijing102206China

During ultradeep oil and gas drilling,fluid loss reducers are highly important for water-based drilling fluids,while preparing high temperature-and salt-resistance fluid loss reducers with excellent rheology and filtration performance remains a ***,a micro-crosslinked amphoteric hydrophobic association copolymer(i.e.,DADC)was synthesized using N,N-dimethyl acrylamide,diallyl dimethyl ammonium chloride,2-acrylamido-2-methylpropane sulfonic acid,hydrophobic monomer,and pentaerythritol triallyl ether *** to the synergistic effects of hydrogen bonds,electrostatic interaction,hydrophobic association,and micro-crosslinking,the DADC copolymer exhibited outstanding temperature-and *** rheological experiments have shown that the DADC copolymer had excellent shear dilution performance and a certain degree of salt-responsive viscosity-increasing *** DADC copolymer could effectively adsorb on the surface of bentonite particles through electrostatic interaction and hydrogen bonds,which bring more negative charge to the bentonite,thus improving the hydration and dispersion of bentonite particles as well as the colloidal stability of the drilling ***,the drilling fluids constructed based on the DADC copolymer exhibited satisfactory rheological and filtration properties(FLHTHP=12 m L)after aging at high temperatures(up to200℃)and high salinity(saturated salt)***,this work provided new insights into designing and fabricating high-performance drilling fluid treatment agents,demonstrating good potential applications in deep and ultradeep drilling engineering.

关键词： Fluid loss reducer Temperature-and salt-resistance Hydrophobic association Amphoteric Micro-crosslinking

Probing the interaction between asphaltene-wax and its effects on the crystallization behavior of waxes in heavy oil via molecular dynamics simulation

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Petroleum Science 2024年第4期21卷 2839-2848页

作者： Yong Hu Xi Lu Hai-Bo Wang ji-Chao Fang Yi-Ning Wu jian Fang Sun SINOPEC Petroleum Exploration and Production Research Institute Shandong Key Laboratory of Oilfield Chemistry School of Petroleum Engineering China University of Petroleum (East China)

High content of asphaltenes and waxes leads to the high pour point and the poor flowability of heavy oil,which is adverse to its efficient development and its transportation in *** the interaction mechanism between asphaltene-wax is crucial to solve these problems,but it is still *** this paper,molecular dynamics simulation was used to investigate the interaction between asphaltenewax and its effects on the crystallization behavior of waxes in heavy *** show that molecules in pure wax are arranged in a paralleled *** wax molecules in heavy oil,which are close to the surface of asphaltene aggregates,are bent and arranged *** the mass fraction of asphaltenes in asphaltene-wax system(ωasp) is 0-25 wt%,the attraction among wax molecules decreases and the bend degree of wax molecules increases with the increase of ω*** ωaspincreases from 0 to 25 wt%,and the attraction between asphaltene-wax is stronger than that among *** causes that the wax precipitation point changes from 353 to 333 *** the ωaspincreases to 50 wt%,wax molecules are more dispersed owing to the steric hindrance of asphaltene aggregates,and the interaction among wax molecules transforms from attraction to *** causes that the ordered crystal structure of waxes can't be formed at normal ***,the asphaltene,with the higher molecular weight or the more hetero atoms,has more obvious inhibition to the formation of wax ***,resins also have an obvious inhibition on the wax crystal due to the formation of asphalteneresin aggregates with a larger *** results reveal the interaction mechanism between asphaltene-wax,and provide useful guidelines for the development of heavy oil.

关键词： Heavy oil Interaction mechanism Asphaltenes Waxes Molecular dynamics

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大型水电站厂房蜗壳结构形式研究

中国农村水利水电 2006年第1期 69-72页

作者：秦亮练继建郑伟天津大学建筑工程学院天津300072

以某大型水电站厂房蜗壳结构形式研究为背景分别从静力、动力2个方面论述了不同形式的蜗壳结构对电站结构的影响。得出结论认为不同的蜗壳结构形式对电站厂房结构的影响差别主要集中在静力方面,垫层蜗壳方案下,蜗壳周边应力分布不均,对... 详细信息

以某大型水电站厂房蜗壳结构形式研究为背景分别从静力、动力2个方面论述了不同形式的蜗壳结构对电站结构的影响。得出结论认为不同的蜗壳结构形式对电站厂房结构的影响差别主要集中在静力方面,垫层蜗壳方案下,蜗壳周边应力分布不均,对于蜗壳下部混凝土应力状况改变不大,打压蜗壳更有利于减小蜗壳周边混凝土应力,而各种蜗壳结构形式对厂房整体结构的自振特性与动力响应影响较小。

关键词：水电站垫层蜗壳充水预压蜗壳联合承载

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有限深弹性地基上框架内力的计算方法

水利水电技术 2005年第4期36卷 58-59页

作者：王云仓顾辉练继建天津大学建筑工程学院天津300072 水利部河北水利水电勘测设计研究院天津300250

计算坐落在可压缩层或持力层深度有限的弹性基础上的框架结构,需考虑超静定结构和有限深地基的弹性关系,且在计算过程中需计入地基两侧对称或非对称的边荷载作用,计算时采用有限深弹性地基理论和超静定框架内力的计算方法,使计算模型更... 详细信息

计算坐落在可压缩层或持力层深度有限的弹性基础上的框架结构,需考虑超静定结构和有限深地基的弹性关系,且在计算过程中需计入地基两侧对称或非对称的边荷载作用,计算时采用有限深弹性地基理论和超静定框架内力的计算方法,使计算模型更接近工程实践.

关键词：有限深弹性地基超静定结构边荷载作用内力计算

Network analysis reveals context-dependent structural complexity of social calls in serrate-legged small treefrogs

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Current Zoology 2024年第2期70卷 253-261页

作者： Ke Deng Qiao-Ling He Tong-liang Wang ji-Chao Wang jian-Guo Cui CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization&Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041China University of Chinese Academy of Science Beijing 100049China Ministry of Education Key Laboratory for Ecology of Tropical lslands Key Laboratory of Tropical Animal and Plant Ecology of Hainan ProvinceCollege of Life SciencesHainan Normal UniversityHaikou 571158China

Vocal communication plays an important role in survival,reproduction,and animal social *** and mammals produce com-plex vocal sequence to convey context-dependent *** are conspicuous features of the behavior of most anuran species(frogs and toads),and males usually alter their calling strategies according to ecological context to improve the attractiveness/***,very few studies have focused on the variation of vocal sequence in *** the present study,we used both conventional method and network analysis to investigate the context-dependent vocal repertoire,vocal sequence,and call network structure in serrate-legged small treefrogs Kurixalus *** found that male *** modified their vocal sequence by switching to different call types and increasing repertoire size in the presence of a competitive ***,compared with before and after the playback of advertisement calls,males emited fewer advertisement calls,but more aggressive calls,encounter calls,and compound calls during the playback *** analysis revealed that the mean degree,mean closeness,and mean betweenness of the call networks significantly decreased during the playback period,which resulted in lower *** addition,the increased proportion of one-way motifs and average path length also indicated that the connectivity of the call network decreased in competitive ***,the vocal sequence of *** did not display a clear small-world network structure,regardless of *** study presents a paradigm to apply network analysis to vocal sequence in anurans and has important implications for understanding the evolution and function of sequence patterns.

关键词： call network centrality Kurixalus odontotarsus vocal repertoire vocal sequence.

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基于小波消噪的混沌多元回归日径流预测模型

系统仿真学报 2007年第15期19卷 3605-3608页

作者：王秀杰练继建费守明张卓天津大学建工学院天津300072 天津市水利基建管理处天津300204

基于小波消噪理论对水文序列中的噪声进行了处理,然后利用混沌理论中的相空间重构技术计算出饱和嵌入维数作为多元回归模型的可控变量个数,将小波、混沌和多元回归方法结合起来对日径流进行了预测。与消噪前相比,消噪处理后建立的模型... 详细信息

基于小波消噪理论对水文序列中的噪声进行了处理,然后利用混沌理论中的相空间重构技术计算出饱和嵌入维数作为多元回归模型的可控变量个数,将小波、混沌和多元回归方法结合起来对日径流进行了预测。与消噪前相比,消噪处理后建立的模型预测精度有了明显提高:预测合格率提高8%,平均绝对百分比误差为9.53%。因此在对水文时间序列进行混沌分析和预测之前,对其进行小波消噪是完全必要的。

关键词：多元回归模型日径流预测小波消噪混沌嵌入维数

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混流式水轮机轴向动荷载识别

振动与冲击 2007年第4期26卷 123-125页

作者：王海军练继建杨敏王日宣天津大学建筑工程学院天津300072

水轮机轴向动荷载是机组总轴向力的主要组成部分,其特性直接影响水电站厂房设计和安全经济运行。合理对其进行评估具有重要的意义。文中以一水电站厂房结构和机组联合现场振动测试数据为基础,将厂房结构和机组视为一耦联体系,采用改进... 详细信息

水轮机轴向动荷载是机组总轴向力的主要组成部分,其特性直接影响水电站厂房设计和安全经济运行。合理对其进行评估具有重要的意义。文中以一水电站厂房结构和机组联合现场振动测试数据为基础,将厂房结构和机组视为一耦联体系,采用改进遗传算法和有限元技术编写程序,对水轮机轴向动荷载进行识别。识别结果比较理想。该方法简单有效,具有较强的实用性。

关键词：水电站轴向动荷载识别技术遗传算法有限元

粉砂中筒型基础沉贯过程筒–土作用机理试验研究

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岩土工程学报 2015年第4期37卷 683-691页

作者：陈飞练继建马煜祥张杰卜同胜天津大学水利工程仿真与安全国家重点实验室天津300072 水利部水利水电规划设计总院北京100120

筒型基础沉贯安装是一项关键施工过程,目前相关研究多集中在沉贯阻力与吸力的计算方法上,而缺乏对沉贯过程筒–土作用机理研究。针对这一问题,开展了粉砂中筒型基础沉贯试验,得到了静压和吸力沉贯工况下筒壁内、外侧所受土压力发展变化... 详细信息

筒型基础沉贯安装是一项关键施工过程,目前相关研究多集中在沉贯阻力与吸力的计算方法上,而缺乏对沉贯过程筒–土作用机理研究。针对这一问题,开展了粉砂中筒型基础沉贯试验,得到了静压和吸力沉贯工况下筒壁内、外侧所受土压力发展变化规律。静压试验结果表明,筒壁内侧所受土压力远大于外侧,内侧土体挤压程度随下沉深度增加而增大,外侧相反。吸力试验结果表明,施加吸力时内侧土压力减小,外侧土压力先增大后迅速减小至稳定值,吸力产生的渗流可以大大减小端阻力与内侧摩阻力。试验结果还表明现有临界吸力计算公式是过于保守的,并根据试验结果对现有计算所需吸力的方法进行了修正,得到了一种更加准确的计算方法。

关键词：吸力减阻贯入阻力筒壁土压力