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黑山南北高速公路板式桥梁横梁计算方法的研究

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公路 2024年第2期69卷 19-23页

作者：凤跃森郑君长简佳峰中交第一公路勘察设计研究院有限公司西安市710068 中国路桥工程有限责任公司北京市100011

以黑山南北高速公路连接线处的DRCKA桥为研究对象,对其桥墩处横梁建立若干局部分析模型,参考国内横梁分析方法提出了恒载及活载的施加方式,进而对其进行配筋及裂缝计算,并与该桥整体结构模型分析的结果进行了对比。结果表明,所述横梁局... 详细信息

以黑山南北高速公路连接线处的DRCKA桥为研究对象,对其桥墩处横梁建立若干局部分析模型,参考国内横梁分析方法提出了恒载及活载的施加方式,进而对其进行配筋及裂缝计算,并与该桥整体结构模型分析的结果进行了对比。结果表明,所述横梁局部分析模型计算结果能够较好地与整体结构模型计算结果相吻合,在实际工程应用中可采用局部模型进行计算,以简化横梁计算工作。

关键词：桥梁工程板式桥横梁局部模型剪力计算方法研究

前南斯拉夫地区桥梁设计规范与中国规范关于汽车荷载的对比分析研究

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公路 2024年第2期69卷 30-33页

作者：蔡锋高翊宸孙文涛简佳峰中交第一公路勘察设计研究院有限公司西安市710068

分别以我国及前南斯拉夫地区典型高速公路桥梁为研究对象,采用有限元分析软件Midas/Civil对桥梁建立模型,计算其在前南斯拉夫规范和我国规范规定的汽车荷载作用下的效应值。计算结果表明,前南斯拉夫地区桥梁设计规范中汽车荷载效应与我... 详细信息

分别以我国及前南斯拉夫地区典型高速公路桥梁为研究对象,采用有限元分析软件Midas/Civil对桥梁建立模型,计算其在前南斯拉夫规范和我国规范规定的汽车荷载作用下的效应值。计算结果表明,前南斯拉夫地区桥梁设计规范中汽车荷载效应与我国15规范大致吻合(差异在20%左右),在对这类桥梁进行初步设计或施工图设计时,辅以必要的调整系数,采用我国15规范对其进行结构尺寸或配筋的初拟,基本可以满足前南斯拉夫规范要求。本研究成果可为我国境外桥梁工程项目设计提供参考。

关键词：桥梁工程汽车荷载前南斯拉夫规范中国规范对比分析研究

领导-成员交换组合对追随力的影响--传统性和感知人力资源管理强度的调节作用

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管理科学学报 2024年第7期27卷 84-99页

作者：贾建锋赵若男蔡亚华刘伟鹏东北大学工商管理学院沈阳110169 工业智能与系统优化国家级前沿科学中心沈阳110819 智能工业数据解析与优化教育部重点实验室沈阳110819 上海财经大学商学院上海200433

随着员工地位提升,员工追随力的激发成为组织关心的议题.从员工和领导对彼此关系质量(LMX)感知存在不对等的现象入手,基于角色理论,本研究构建了员工和领导的LMX组合对追随力影响的理论模型并考察了传统性和感知人力资源管理强度的边界... 详细信息

随着员工地位提升,员工追随力的激发成为组织关心的议题.从员工和领导对彼此关系质量(LMX)感知存在不对等的现象入手,基于角色理论,本研究构建了员工和领导的LMX组合对追随力影响的理论模型并考察了传统性和感知人力资源管理强度的边界作用.通过收集75位领导和350位员工的配对样本数据,并进行潜在剖面分析、多项式回归和响应面分析,研究发现:员工和领导之间存在四种LMX组合.具体来说,“高-高”组合比“低-低”组合更容易激发追随力;“高-低”组合比“低-高”组合更容易激发追随力.同时,LMX不同组合与追随力之间的关系也受到传统性和感知人力资源管理强度的调节.具体来说,高传统性下,“高-高”组合和追随力之间的关系与“低-低”组合相比得到了增强,“低-高”组合和追随力之间的关系与“高-低”组合相比得到了增强;高感知人力资源管理强度下,“低-低”组合和追随力之间的关系与“高-高”组合相比得到了增强,“高-低”组合和追随力之间的关系与“低-高”组合相比得到了增强.研究深化了LMX组合对追随力产生的差异影响及其边界作用,为解决员工和领导关系不对等问题提供了理论依据和实证支持.

关键词：领导-成员交换组合追随力传统性感知人力资源管理强度角色理论

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电力工程施工管理中存在的问题及应对办法

电站系统工程 2024年第5期40卷 77-78页

作者：贾剑锋吕国芳王宝山中国机械设备工程股份有限公司哈尔滨电站设备成套设计研究所有限公司

电力施工管理中存在的问题包括进度延误、质量不稳定、安全风险高和成本控制不力。为解决这些问题,应采取适当的应对办法,包括建立有效的进度管理机制、加强质量监控、强化安全管理和制定详细的成本计划。

关键词：电力工程施工管理应对办法

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电力工程施工项目管理及成本控制重点探寻

电站系统工程 2024年第4期40卷 83-84页

作者：贾剑锋王辰吕国芳吴楠魏经明中国机械设备工程股份有限公司哈尔滨电站设备成套设计研究所有限公司

电力施工项目管理及成本控制是电力行业的重要组成部分,对于提高项目的管理水平和经济效益至关重要。电力施工项目管理及成本控制是电力行业中非常重要的一项工作。因此对电力工程管理模式的创新与成本控制,展开相关分析。

关键词：电力施工项目管理成本控制措施方法

Theoretical Analysis of the Mechanism of Cationic Pd(Ⅱ)-catalyzed Fujiwara-Moritani Reaction

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Chinese Journal of Structural Chemistry 2021年第5期40卷 576-587,528页

作者： REN Ying WANG Tao ZHANG Ting-Ting jia jian-feng WU Hai-Shun Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education School of Chemistry and Materials ScienceShanxi Normal UniversityLinfen 041000China

A systematic theoretical investigation has been studied on Fujiwara-Moritani reaction between 3-methoxyacetanilide with n-butyl acrylate by means of density functional theory(DFT) calculations when two types of Pd(Ⅱ) catalysts are employed. In [Pd(MeCN)_4](BF_4)_2 catalytic cycle, a 1,4-benzoquinone(BQ)-induced C-H activation of trans-(MeCN)_2Pd(BQ)~(2+) with 3-methoxyacetanilide occurs as the first step to give DC-4_(MeCN), facilitating the insertion of n-butyl acrylate and β-hydride elimination, followed by recycling of catalyst through hydrogen abstraction of monocationic BQ fragment. In Pd(OAc)_(2) catalytic cycle, it is proposed that the most favored reaction pathway should proceed in dicationic mechanism involving a BQ-assisted hydrogen transfer for C-H activation by Pd active catalyst(HOAc)_(2)Pd(BQ)^(2+) to generate DC-4_(HOAc), promoting acrylate insertion and β-hydride elimination, followed by the regeneration of catalyst to give the final product. The calculations indicate that the rate-determining step in [Pd(MeCN)_(4)](BF_4)_(2) catalytic system is the acrylate insertion, while it is the regeneration of catalyst in the Pd(OAc)_(2) catalytic system. In particular, the roles of BQ and ligand effects have also been investigated.

关键词： C-H bond activation DFT studies Pd(Ⅱ)catalyst reaction mechanism

The noise spectral characteristics and noise reduction schemes of screw air-source heat pump:A case study

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Building Simulation 2024年第1期17卷 53-70页

作者： Dongsheng Liu Yaohan feng Jikang jia Pengfei Si Ya feng China Southwest Architecture Design and Research Institute Co.Ltd. Chengdu 610041China CSCEC Green Construction Engineering Research Center Chengdu 610041China

The screw air-source heat pump can cause incessant high noise levels during operation,which might hinder adoption of this energy-efficient heat ***,acoustic measurements and comparison testing were performed in this *** measurements revealed that the compressor is the main noise source of the heat pump,and it shows a multipeak frequency distribution and a wide frequency spectrum under different work conditions,with multiple peaks at 63,250,and 1000 ***,a compressor sound insulation cover with broadband absorption was proposed,and it was experimentally proven that the insulation cover can reduce the maximum sound pressure level of one unit from 89.8 dBA to 79.1 ***,we proposed several noise reduction strategies and compared their noise reduction effects using computer *** results showed that the noise problem can be effectively improved through the rational design of the sound barrier and the layout and opening options of heat *** distance between the sound barrier and heat pump and the sound attenuation due to diffraction ALa exhibit a U-shaped *** buildings of different heights,the optimal heights of noise barrier are *** 5.5-meter is the optimal height of the sound barrier for single-story *** conclusions can be applied to other building projects for heat pump noise reduction.

关键词： acoustic simulation broadband noise noise reduction air-source heat pump sound barrier

Grain refinement of 5A06 aluminum alloy welds caused by tungsten inert gas welding arc characteristics under Ar-He alternating gas supply conditions:a coupled method of water-cooled copper plate test/numerical simulation

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Journal of Iron and Steel Research International 2024年第3期31卷 767-777页

作者： Hong-bin Dai jian Miao jia-xin Lin School of Materials Science and Engineering Harbin University of Science and TechnologyHarbin 150040HeilongjiangChina

The welding arc,as a carrier for the conversion of electrical energy to thermal energy,has a direct impact on the quality of welding by its properties and *** the tungsten inert gas(TIG)welding process under the condition of Ar-He alternating gas supply,the arc is alternately converted between Ar arc and He arc with an alternating gas supply cycle,which has obvious arc change *** FLUENT software was used to numerically simulate the characteristics of the TIG arc under the condition of alternating gas supply,and the arc temperature field,arc pressure,electric potential and current density distribution under the condition of alternating gas supply were *** with the real-time data of arc pressure measured by the water-cooled copper plate with holes,it is proved that the TIG arc has obvious dynamic characteristics under the condition of Ar-He alternating gas *** unique dynamic TIG arc acts on the 5A06 aluminum alloy weld,causing the molten pool to stir,resulting in uniform microstructure and grain refinement at the weld,and thereby improving the mechanical properties of the welded joint.

关键词： Alternating gas supply Grain refinement Numerical simulation Tungsten argon arc morphology Microstructure Mechanical property

Calmodulin-like 5 promotes PEDV replication by regulating late-endosome synthesis and innate immune response

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Virologica Sinica 2024年第3期39卷 501-512页

作者： Wen-Jun Tian Xiu-Zhong Zhang Jing Wang jian-feng Liu Fu-Huang Li Xiao-jia Wang National Key Laboratory of Veterinary Public Health and Safety College of Veterinary MedicineChina Agricultural UniversityBeijing 100193China College of Animal Science and Technology China Agricultural UniversityBeijing 100193China Beijing General Station of Animal Husbandry Service(South Section) Beijing102218China

The infection caused by porcine epidemic diarrhea virus(PEDV)is associated with high mortality in piglets *** factors involved in the efficient replication of PEDV,however,remain largely *** recent proteomic study in the virus-host interaction network revealed a significant increase in the accumulation of CALML5(EF-hand protein calmodulin-like 5)following PEDV infection.A further study unveiled a biphasic increase of CALML5 in 2 and 12 h after viral *** trends were observed in the intestines of piglets in the early and late stages of the PEDV ***,CALML5 depletion reduced PEDV mRNA and protein levels,leading to a one-order-of-magnitude decrease in virus *** the early stage of PEDV infection,CALML5 affected the endosomal trafficking pathway by regulating the expression of endosomal sorting complex related cellular ***5 depletion also suppressed IFN-βand IL-6 production in the PEDV-infected cells,thereby indicating its involvement in negatively regulating the innate immune *** study reveals the biological function of CALML5 in the virology field and offers new insights into the PEDV-host cell interaction.

关键词： Porcine epidemic diarrhea virus(PEDV) EF-hand protein calmodulin-like 5(CALML5) Late endosomes Innate immune response