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考虑界面黏结滑移的聚丙烯纤维混凝土梁弯剪破坏特征研究

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公路 2025年第2期70卷 105-114页

作者：张君健王华逸周明刘新华何雄君湖北交投鄂西高速公路建设管理有限公司武汉理工大学交通与物流工程学院中交第二公路勘察设计研究院有限公司

掺加聚丙烯纤维是提高混凝土开裂性能的有效途径之一。基于混凝土塑性损伤模型和内聚力模型考虑聚丙烯纤维增强混凝土(PFRC)和钢筋—混凝土界面的非线性行为，研究PFRC—钢筋梁的抗弯剪性能。建立有限元模型对掺加不同体积比纤维用量的P... 详细信息

掺加聚丙烯纤维是提高混凝土开裂性能的有效途径之一。基于混凝土塑性损伤模型和内聚力模型考虑聚丙烯纤维增强混凝土(PFRC)和钢筋—混凝土界面的非线性行为，研究PFRC—钢筋梁的抗弯剪性能。建立有限元模型对掺加不同体积比纤维用量的PFRC梁进行了数值分析，通过定义不同的材料模型来描述梁在弯剪作用下的开裂行为。结果表明，聚丙烯纤维能有效提升混凝土抵抗弯剪破坏的能力，采用黏聚力单元模拟界面黏结滑移能更准确地描述梁的开裂特征。研究结果对于理解聚丙烯纤维维对PFRC梁抗弯剪性能的影响具有较高的参考价值。

关键词：桥梁工程聚丙烯纤维增强混凝土梁混凝土塑性损伤模型内聚力模型数值分析

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Temperature Dependence of Atomic Decay Rate

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Chinese Physics Letters 2012年第2期29卷 75-78页

作者： zhang jian-jun CHENG Ze Department of Physics Huazhong University of Science and TechnologyWuhan 430074

We investigate the decay rate of an atom in a two-dimensional optical microcavity in which there exists a BoseEinstein condensation of *** is found that below the critical temperature To,the atomic decay rate depends on the absolute temperature ***,at absolute zero temperature almost all photons are in the condensate state,and the atom can be approximately treated as if it is in vacuum.

关键词： absolute decay approximate

Thermal Decomposition Kinetics and Mechanism of Tb(Ⅲ) m-Methylbenzoate Complex with 1,10-Phenanthroline in Static Air Atmosphere

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Chemical Research in Chinese Universities 2002年第1期18卷 25-29页

作者： zhang jian-jun WANG Rui-fen zhang jian-ling WANG Shu-ping Experimental Center Hebei Normal UniversityShijiazhuang 050016P.R.China Department of Chemistry Hebei Normal UniversityShijiazhuang 050091.P.R.China Institute of Chemistry Chinese Academy of SciencesBeijing 100080P.R.China

The thermal behavior of [Tb_2( m -MBA)_6(phen)_2](H_2O)_2( m -MBA=C_8H_7O_2, methoxybenzoate; phen=C_ 12 H_8N_2, 1,10-phenanthroline) in static air atmosphere was investigated by means of TG-DTG and DTA methods. The thermal decomposition of the title compound takes place mainly in two steps. The intermediate and the residue for each decomposition were identified by the TG curve. By the kinetic method of processing thermal analysis data put forward by Malek et al ., it is defined that the kinetics model for the first-step thermal decomposition is SB( m,n ).

关键词： Thermal decomposition Non-isothermal kinetics Tb(Ⅲ) complex m-Methylbenzoate 1,10-Phenanthroline

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地方自主运营城际铁路客流提升策略

交通企业管理 2025年第1期40卷 31-33页

作者：陶涛杨东剑张建军马丽深圳市地铁集团有限公司

近年来,伴随我国城市化水平不断提高,城市群和都市圈之间的联系日益紧密,人们对于快速、便捷的交通出行需求也日益增长。城际铁路作为一种高效、环保的交通方式,在连接城市间、促进区域经济发展中发挥着重要作用。然而,随着市场竞争的... 详细信息

近年来,伴随我国城市化水平不断提高,城市群和都市圈之间的联系日益紧密,人们对于快速、便捷的交通出行需求也日益增长。城际铁路作为一种高效、环保的交通方式,在连接城市间、促进区域经济发展中发挥着重要作用。然而,随着市场竞争的加剧和旅客出行需求的变化,地方自主运营的城际铁路面临着经营压力大、客票收入不高等问题。因此.

关键词：地方自主运营城际铁路客流特征运力配置品牌建设多元化服务

Broadband channel measurement and analysis

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The Journal of China Universities of Posts and Telecommunications 2006年第3期13卷 24-28页

作者： zhang Ming zhang jian-hua jianG jun zhang Ping WU Yu-fei Wireless Technology Innovation Labs (WTI) Beijing University of Posts and Telecommunications Beijing 100876 China

An outdoor propagation measurement campaign for beyond 3G （B3G） as well as a wide-band indoor measurement campaign have been performed recently in Beijing, China, in which the sounding signals are transmitted by an one-antenna base station and received by a two-antenna mobile receiver operated at 3.49～3.51 GHz bandwidth. Different scenarios： stationary line-of-sight （LoS）, stationary non-LoS （NLoS） scenarios, and dynamic NLoS are deliberately chosen in a classic urban environment and office environment. The initial results are presented in this article. Parameters including vector channel impulse response, path loss, rays number, excess delay spread etc. are extracted, analyzed, and briefly reported here.

关键词： Broadband measurement Beyond 3G path loss,multipath delay rays number

Preparation, Crystal Structure and Thermal Decomposition Process of Dysprosium Benzoate Complex with 1,10-Phenanthroline

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Chinese Journal of Structural Chemistry 2008年第2期27卷 233-237页

作者： XU Su-Ling zhang jian-jun REN Ning zhang Hai-Yan HU Rui-Sheng Experimental Center Hebei Normal UJziversity Shijiazhuang 050016 China Department of Engineering Shijiazhuang Foreign Economy and Trade Vocational College Shijiazhuang 050061 China Department of Chemistry Handan College Handan 056005 China School of Chemical Engineering Shijiazhuang College Shijiazhuang 050035 China

A dinuclear dysprosium（III） complex with benzoic acid and 1,10-phenanthroline, [Dy（BA）3phen]2 （BA = benzoate, PHEN = 1,10-phenanthroline）（C66H46Dy2NaO12, Mr = 1412.07） was synthesized and characterized by elemental analysis, UV, IR, X-ray diffraction, molar conductance and TG-DTG techniques. It crystallizes in triclinic, space group P1 with a = 10.773（2）, b = 11.933（3）, c = 12.417（5） A, α= 105.226（3）,β= 93.470（3）, γ= 113.475（2）°, V= 1388.0（7）, Z = 1, Dc = 1.689 g/cm3, μ（MoKa） = 2.742 mm-1 and F（000） = 698. R = 0.0210, wR = 0.0538. In the crystal, each Dy（III） ion is eight-coordinated by one bidentate chelating carboxylate group, four bidentate bridging carboxylate groups and one 1,10-phenanthroline molecule. The thermal decomposition process of [Dy（BA）3phen]2 has been determined by thermal analysis.

关键词： benzoic acid crystal structure 1,10-phenanthroline dysprosium complex thermal analysis

Seasonal variations in the influence of vegetation cover on soil water on the loess hillslope

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Journal of Mountain Science 2020年第9期17卷 2148-2160页

作者： SHEN Ming-shuang zhang jian-jun zhang Shou-hong zhang Hai-bo SUN Ruo-xiu zhang Yi-zhou School of Soil and Water Conservation Beijing Forestry UniversityBeijing 100083China National Station for Forest Ecosystem Research in Ji County Ji County 042200Shanxi ProvinceChina

Soil water is the key factor that restricts the restoration of the local ecological systems in the Loess Plateau of *** the effects of vegetation types on soil water and its seasonal variation helps to understand hydrological characteristics and provides insights into the sustainable restoration of ***,the Caijiachuan watershed was chosen as the research object to investigate the water status of a 0-10 m soil layer under different vegetation types including Pinus tabulaeformis,Robinia pseudoacacia,Platycladus orientalis,apple orchard,natural forestland,farmland and *** comparing the difference between soil water of different land use types and that of grassland during the same period,the seasonal changes of soil water status of different types were *** results show that(1)in the 0-10 m soil layer,the largest value of soil water content was in the0.3-0.4 m layer,and the lowest was in the 5.6-5.8 m *** depths at which the vegetation cover influenced the soil water were up to 10 m;(2)among summer,fall and spring,the soil water storage wasthe highest in the *** addition,the lowest value of relative accumulation was in the fall,which was the period in which the soil water recovered;(3)the soil water in the 0-10 m layer was in a relatively deficient state in the artificial forestlands,apple orchards and native forestlands,while the relative accumulation was in the *** addition,the relative deep soil layers(8-10 m)had more serious deficits in the areas in which ***,*** and the apple orchard grew;(4)during the study period,the farmland in the summer had the largest relative accumulation(182.71 mm),and the land under *** in the fall had the lowest relative deficit(512.20 mm).In the Loess Plateau,vegetation cover will affect the change of deep soil moisture and artificial forest will cause soil water loss in different degrees.

关键词： Seasonal variation Soil water Vegetation cover Hillslope Loess Plateau

Effects of Carrier Gas on Carbon Incorporation in GaN

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Chinese Physics Letters 2014年第3期31卷 122-124页

作者： zhang jian-Li LIU jun-Lin PU Yong FANG Wen-Qing zhang Meng jianG Feng-Yi National Engineering and Technology Research Center for LED on Si Substrate Nanchang University Nanchang 330047

GaN epitaxial layers were grown on Si （111） substrates by metal organic chemical vapor deposition. Carbon concentrations in the films grown in different ambients were measured by secondary ion mass spectrometry. The results show that the carbon incorporation is strongly dependent on the H2 flow rate when the NH3 flow rate is small, but insensitive to the H2 flow rate when the NH3 flow rate is sufficient large. We conclude that H2 can inhibit the dissociation of NH3 and result in a less active N source; an insufficiently active N source causes more N vacancies, which enhances carbon incorporation.

关键词： Gallium nitride

An improved method of potential of mean force for protein-protein interactions

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Chinese Science Bulletin 2008年第8期53卷 1145-1151页

作者： SU Yux LI WenFei zhang jian WANG jun WANG Wei National Laboratory of Solid State Microstructure and Department of Physics Nanjing University Nanjing 210093 China

In this work, the traditional method of potential of mean force (PMF) is improved for describing the protein-protein interactions. This method is developed at atomic level and is distance-dependent. Compared with the traditional method, our model can reasonably consider the effects of the environ- mental factors. With this modification, we can obtain more reasonable and accurate pair potentials, which are the pre-requisite for precisely describing the protein-protein interactions and can help us to recognize the interaction rules of residues in protein systems. Our method can also be applied to other fields of protein science, e.g., protein fold recognition, structure prediction and prediction of thermo- stability.

关键词：基础知识 PMF 双蛋白交互作用