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地应力影响下的五孔掏槽爆破岩石损伤效应研究

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火工品 2025年第1期 89-96页

作者：杨赛群葛立芳李洪伟夏治园安徽江南爆破工程有限公司安徽宣城242000 安徽江南化工股份有限公司安徽合肥230088 安徽理工大学化工与爆破学院安徽淮南232001

在地下矿山开采过程中,地应力对巷道掘进效率的影响日益显著。本研究以某地下铁矿为研究对象,采用有限元软件LS-DYNA模拟不同地应力条件下五孔掏槽爆破掏槽孔孔间延期时间对岩石损伤程度的影响。通过现场爆破实验和块度识别软件验证模... 详细信息

在地下矿山开采过程中,地应力对巷道掘进效率的影响日益显著。本研究以某地下铁矿为研究对象,采用有限元软件LS-DYNA模拟不同地应力条件下五孔掏槽爆破掏槽孔孔间延期时间对岩石损伤程度的影响。通过现场爆破实验和块度识别软件验证模拟结果,探究了地应力、孔间延期时间与岩石损伤程度之间的关系。研究结果表明,地应力由0 MPa增加到10 MPa,五孔掏槽爆破掏槽孔最佳延期时间由60 ms减少为10 ms,相应的岩石损伤程度降低79%。地应力对爆破远区岩石裂纹的发育影响较大,而对近区影响较小。现场实验进一步证实了数值模拟的结论,表明可以根据实际地应力大小合理设置延期时间,有效降低大块率,提高爆破效率。

关键词：五孔掏槽爆破地应力延期时间 LS-DYNA 损伤程度

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Brownian Dynamics Simulations of Rigid Polyelectrolyte Chains Grafting to Spherical Colloid

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Chinese Journal of Polymer Science 2018年第6期36卷 791-798页

作者： Qing-Hai Hao Zhen Zheng Gang xia hong-ge Tan College of Science Civil Aviation University of China

Brownian dynamics simulations are employed to explore the effects of chain stiffness and trivalent salt concentration on the conformational behavior of spherical polyelectrolyte brush. The rigid brush adopts bundle-like morphology at a wide range of trivalent salt concentration. The number variation of bundles pinned on the colloid surface shows a non-monotonic profile as a function of the chain stiffness. The radial distributions of monomers and ions and the charge ratio between condensed ions and monomers are calculated. The charge inversion is observed for the high salt concentration regardless of chain rigidity. Furthermore, the pair correlation functions of monomer-monomer and monomer-salt cation are used to elucidate the aggregated mechanism of the bundle-like structure.

关键词： Brownian dynamics simulation Spherical polyelectrolyte brush Chain stiffness Trivalent salt concentration Pinned bundle morphology

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中华绒螯蟹核糖体DNA全序列分析

水产学报 2010年第5期34卷 696-703页

作者：俞菊华李红霞戈贤平李建林唐永凯中国水产科学研究院淡水渔业研究中心农业部水生动物遗传和养殖生物学重点实验室

核糖体DNA通常被选作系统发育研究的分子标记,核糖体DNA中IGS部分序列的变异在一定程度上影响着生物的生长。报道了中华绒螯蟹核糖体DNA全序列的分离和序列特征。中华绒螯蟹核糖体DNA全长11660bp,包括18S(1873bp),ITS1(317bp),5.8S(163b... 详细信息

核糖体DNA通常被选作系统发育研究的分子标记,核糖体DNA中IGS部分序列的变异在一定程度上影响着生物的生长。报道了中华绒螯蟹核糖体DNA全序列的分离和序列特征。中华绒螯蟹核糖体DNA全长11660bp,包括18S(1873bp),ITS1(317bp),5.8S(163bp),ITS2(614bp),28S(4461bp)和IGS(4240bp);不同部分AT含量在40.1%～48.6%之间,低于果蝇(55.8%～80.0%),高于鲤(22.0%～43.7%)。平均100个核苷酸含简单重复序列(SSR)数由高到低依次为ITS2(0.98%),IGS(0.49%),28S(0.38%),ITS1(0.32%),18S(0.21%),5.8S(0%)。个体内差异分析结果表明,中华绒螯蟹个体内存在两类ITS2序列,其中一类在405nt处有一12bp(CGCAGGACCACC)插入序列。中华绒螯蟹rDNA的IGS部分长4240bp,AT含量为42.6%。IGS部分包含一个有约7个连续136～139bp单元组成的重复序列区,重复序列单元中存在XhoⅠ内切酶位点,为河蟹特有的重复序列;重复序列区后有一个由182个碱基对形成的柄和21bp的环组成的发夹结构。中华绒螯蟹核糖体DNA序列的揭示将为继续研究不同地理种群间的差异标记和挖掘与生长率相关的核糖体DNA分子特性提供理论基础。

关键词：中华绒螯蟹核糖体DNA 个体内差异 IGS结构

A New Furostanol Saponin from Dioscorea futshauensis

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Chinese Chemical Letters 2002年第3期13卷 241-244页

作者： hong Wei LIU ge xia QU Xin Sheng YAO Department of Natural Products Chemistry Shenyang Pharmaceutical UniversityShenyang 110015

A new furostanol saponin presenting moderate bioactivity of inducing morphological deformation of Pyricularia oryzae mycelia was isolated from Dioscorea futshauensis *** by bioactivity-guided fractionation. The structure was established as 26-O-b-D-glucopyranosyl-3b, 26-diol-23(S)-methoxyl-(25R)-furost-5,20 (22)-diene-3-O-[a-L-rhamnopyranosyl (12)-b-D- glucopyranosyl (13)]-b-D-glucopyranoside on the basis of chemical evidencesand spectral analysis, especially by 2D-NMR techniques.

关键词： Furostanol glycoside Dioscorea futshauensis Pyricularia oryzae.

教育公平基础上的义务教育资源配置——基于罗尔斯的《正义论》

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邯郸学院学报 2016年第3期26卷 98-100页

作者：苏红霞康香阁周冰毅郭丽娜邯郸学院学报编辑部河北邯郸056005 丛台小学河北邯郸056005

我国教育发展的现状表现为不断增长的教育需求与教育资源相对短缺和教育公平与教育资源非均衡性矛盾,这在一定程度上影响了教育公平的实现。罗尔斯在《正义论》中提出阶级之间的沟壑应通过学校体系的设计填平。根据义务教育公共产品的性... 详细信息

我国教育发展的现状表现为不断增长的教育需求与教育资源相对短缺和教育公平与教育资源非均衡性矛盾,这在一定程度上影响了教育公平的实现。罗尔斯在《正义论》中提出阶级之间的沟壑应通过学校体系的设计填平。根据义务教育公共产品的性质,在义务教育资源配置中,政府角色定位和学校本位需求有助于实现教育资源的最优配置。

关键词：教育公平《正义论》政府定位学校本位

A Control Method for Congested Traffic in the Car-Following Model

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Chinese Physics Letters 2012年第5期29卷 49-51页

作者： ge hong-xia YU Jian LU Zhao-Ming Faculty of Science Ningbo UniversityNingbo 315211 Department of Civil and Architectural Engineering City University of Hong KongKowloonHong Kong

A simple control method to suppress traffic congestion is proposed for the car-following *** stability conditions are derived by using the control method,and the feedback signals,which act on our traffic system,are extended to the car-following *** control signals will play an effect only if the traffic is *** corresponding numerical simulation results agree well with our theoretical analysis,and our control method can successfully suppress traffic jams.

关键词： traffic method stability

Key to the fungus-feeder Phlaeothripinae species from China(Thysanoptera: Phlaeothripidae)

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Zoological Systematics 2014年第3期39卷 313-358页

作者： Li-hong Dang ge-xia Qiao Key Laboratory of Zoological Systematics and Evolution Institute of Zoology Chinese Academy of Sciences Bio-resources Key Laboratory of Shaanxi Province School of Biological Sciences & Engineering Shaanxi University of Technology

In China, 31 genera and 95 species of fungivorous Phlaeothripinae are recorded here, of which 7 species are newly recorded and illustrated. An illustrated identification key to the 94 species is also provided, togethe... 详细信息

关键词： Key Phlaeothripinae fungus-feeder China.

Surface Patterns of a Tetrahedral Polyelectrolyte Brush Induced by Grafting Density and Charge Fraction

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Chinese Journal of Polymer Science 2020年第4期38卷 394-402,I0007页

作者： hong-ge Tan Gang xia Li-xiang Liu xiao-Hui Niu Qing-Hai Hao College of Science Civil Aviation University of ChinaTianjin 300300China

A tetrahedral polyelectrolyte brush in the presence of trivalent counterions is researched under the condition of good solution by mea ns of molecular dynamics simulati *** density and charge fraction are varied to gen erate a series of surface patter *** microphase separation happens and various interesting pinned patches appear at appropriate charge fraction and grafting *** a careful analysis on the brush thickness,the pair correlation functions,the distributions of net charge,and the four states of trivalent counterions in the brush,we find that the ordered surface patterns and special properties are induced by the pure electrostatic correlation effect of trivalent ions even in the good ***,the dependences of electrostatic correlation on the charge fraction of tethered chains are evaluated for fixed grafting den ***,our results can serve as a guide for precise control over the stimuli-responsive materials rational and self-assembly of nanoparticles.

关键词： Surface patterns Tetrahedral polyelectrolyte brush Molecular dyn amics simulation Electrostatic cor relation

A New Spirostanol Saponin from Dioscorea futshauensis

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Chinese Chemical Letters 2001年第7期12卷 613-616页

作者： hong Wei LIU Hisayoshi KOBAYASHI ge xia QU Xin Sheng YAO Department of Natural Products Chemistry Shenyang Pharmaceutical UniversityShenyang 110015 Institute of Molecular&Cellular Biosciences The University of TokyoTokyoJapan 113

A new spirostanol saponin presenting strong activity of inducing morphological deformation of Pyricularia oryzae mycelia was isolated from Dioscorea futshauensis R. Kunth by bioactivity-guided fractionation. The structure was established as (25S)-spirost-5-en-3 beta, 27-diol-3-O- [alpha -L-rhamnopyranosyl (1 -->2)-beta -D glucopyranosyl (1 -->3)]-beta -D-glucopyranoside on the basis of chemical evidences and spectral analysis, especially by 2D-NMR techniques.

关键词： New spirostanol glycoside Dioscorea futshauensis Pyricularia oryzae