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竹原纤维再生骨料混凝土配制与性能研究

混凝土 2024年第4期 166-170,177页

作者：王莹徐彬妤张振文章子华宁波大学土木工程与地理环境学院浙江宁波315211

通过正交试验研究竹原纤维掺量、竹原纤维长度和水灰比对混凝土抗压强度、劈裂抗拉强度、抗弯强度和坍落度的影响,得出竹原纤维混凝土的最佳配合比。并将天然骨料全部替换为再生骨料,采用扫描电子显微镜对竹原纤维在混凝土内的作用机理... 详细信息

通过正交试验研究竹原纤维掺量、竹原纤维长度和水灰比对混凝土抗压强度、劈裂抗拉强度、抗弯强度和坍落度的影响,得出竹原纤维混凝土的最佳配合比。并将天然骨料全部替换为再生骨料,采用扫描电子显微镜对竹原纤维在混凝土内的作用机理进行了研究分析。试验结果表明:掺竹原纤维受压试件破坏时具有良好的整体性,纤维在混凝土内部起到了一定的拉结作用;竹原纤维混凝土的最优配合比为竹纤维长度20 mm、竹纤维掺量4 kg/m3、水灰比0.55;竹原纤维-硬化水泥浆体界面过渡区内几乎没有片状的Ca(OH)2晶体,纤维与水泥浆体的界面黏结良好。

关键词：竹原纤维再生混凝土正交试验微观结构

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车路协同背景下路侧智慧综合杆安装技术研究

工程技术研究 2024年第4期9卷 76-78页

作者：魏冉明张子华北京亦庄数字基础设施科技发展有限公司北京100176 北京工业大学材料与制造学部北京100124

在智能交通系统快速发展的背景下,文章针对车路协同技术中路侧智慧综合杆的安装技术进行了深入研究,分析了路侧智慧综合杆在结构设计、功能配置和技术参数方面的关键要求,研究了安装前的准备工作及详细的安装流程,强调了在施工过程中注... 详细信息

在智能交通系统快速发展的背景下,文章针对车路协同技术中路侧智慧综合杆的安装技术进行了深入研究,分析了路侧智慧综合杆在结构设计、功能配置和技术参数方面的关键要求,研究了安装前的准备工作及详细的安装流程,强调了在施工过程中注意安全和质量控制的重要性,并提出了针对智慧综合杆的维护策略,以保证其长期稳定运行。研究结果表明,通过采取相关措施能显著提高智慧综合杆的运行效率和可靠性,对智能交通系统的建设和发展具有重要意义。

关键词：车路协同技术路侧智慧综合杆智能交通系统

政府环保补贴对企业业绩的影响——绿色创新的中介作用

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辽宁工程技术大学学报（社会科学版） 2024年第3期26卷 204-213页

作者：李九斤张子华东北石油大学经济管理学院黑龙江大庆163318 中国财政科学研究院北京100142

基于A股制造业上市公司2015—2021年的面板数据,探究政府环保补贴对制造业企业业绩的影响及其影响机制。结果表明:政府环保补贴和企业业绩呈正相关关系,对制造业企业业绩起促进作用;机制检验表明,绿色创新在政府环保补贴对企业长期业绩... 详细信息

基于A股制造业上市公司2015—2021年的面板数据,探究政府环保补贴对制造业企业业绩的影响及其影响机制。结果表明:政府环保补贴和企业业绩呈正相关关系,对制造业企业业绩起促进作用;机制检验表明,绿色创新在政府环保补贴对企业长期业绩的影响中起部分中介作用;异质性分析发现,政府环保补贴对非国有企业业绩的促进作用更为显著,对东部地区企业长期业绩提升作用更强,对大规模企业短期业绩的促进作用更大。

关键词：环保补贴制造业企业企业业绩绿色创新

地榆皂苷Ⅱ对耐甲氧西林金黄色葡萄球菌的抗菌活性及作用机制研究

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药物评价研究 2024年第1期47卷 103-108页

作者：张子桦吴金婵余咏诗张淼菲张凯嘉曾芝璇卓燕萍杨烨健陈鑫佛山科学技术学院医学院广东佛山528225 佛山科学技术学院食品科学与工程学院广东佛山528225 佛山市中医院广东佛山528225

目的考察地榆皂苷Ⅱ对耐甲氧西林金黄色葡萄球菌(methicillin-resistant Staphylococcus aureus,MRSA)的体外抑菌活性以及抑菌机制。方法肉汤稀释法检测地榆皂苷Ⅱ对16株MRSA的体外抑菌活性;比浊法和菌落计数绘制地榆皂苷Ⅱ对MRSA的... 详细信息

目的考察地榆皂苷Ⅱ对耐甲氧西林金黄色葡萄球菌(methicillin-resistant Staphylococcus aureus,MRSA)的体外抑菌活性以及抑菌机制。方法肉汤稀释法检测地榆皂苷Ⅱ对16株MRSA的体外抑菌活性;比浊法和菌落计数绘制地榆皂苷Ⅱ对MRSA的生长曲线、杀菌曲线;通过DNA外泄实验,分析地榆皂苷Ⅱ对MRSA细胞壁膜通透性的影响;通过DAPI染色后的荧光强度分析,考察地榆皂苷Ⅱ对MRSA DNA和RNA的影响。结果地榆皂苷Ⅱ对16株MRSA的最小抑菌浓度(MIC)范围为128~256μg·mL^(-1),最小杀菌浓度(MBC)范围为2~8mg·mL^(-1)。生长曲线结果显示,地榆皂苷Ⅱ质量浓度为1×MIC(256μg·mL^(-1))及以上时,生长抑制作用明显;杀菌曲线结果显示,地榆皂苷Ⅱ2×MIC、4×MIC作用1 h后对MRSA的抑制作用明显,8×MIC、16×MIC分别作用1、2 h后对MRSA起到了完全抑制的作用。2×MIC的地榆皂苷Ⅱ作用于MRSA后,胞外核酸大分子含量显著高于对照组,6 h后核酸外泄量较对照组高26.23%(P<0.05)。地榆皂苷Ⅱ作用于MRSA菌体后,MRSA DNA和RNA水平明显低于对照组(P<0.01、0.001)。结论地榆皂苷Ⅱ对MRSA有良好的抑菌活性,可以通过抑制细菌核酸合成进而抑制MRSA的生长。

关键词：耐甲氧西林金黄色葡萄球菌地榆皂苷Ⅱ 抗菌细胞壁膜通透性核酸合成

The effect of slow shot speed and casting pressure on the 3D microstructure of high pressure die casting AE44 magnesium alloy

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Journal of Magnesium and Alloys 2023年第2期11卷 753-761页

作者： Chaosheng Ma Wenbo YU Tongtong zhang zihua zhang Yihu Ma Shoumei Xiong Center of Materials Science and Engineering School of Mechanical and Electronic Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Research Center of Rail Vehicles Safety Monitoring and Health Management Beijing Jiaotong UniversityBeijing 100044China School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

3D reconstruction and 2D observation were conducted to characterize the microstructure of the castings produced through high pressure die casting with different parameters.Our results indicate that shrinkage pores generally co-existed with externally solidiﬁed crystals(ESCs).In specimen produced without fast slow shot speed,big net-shrinkage pores accompanied with ESCs were found in the center of the specimen.When the casting pressurization was introduced,the shrinkage pores gathered to the specimen center and became much less due to the optimization of melt feeding.Much more porosity was found near the gate rather than in the middle of the rod bar,especially gas pores.Theﬁlling process simulation reveals that the middle position of the bars wasﬁrstlyﬁlled and followed by the near gate position accompanied with one intense turbulentﬂow.

关键词： HPDC parameters Externally solidiﬁed crystals(ESCs) Porosity 3D reconstruction.

Study on the interfacial shear behavior of steel reinforced concrete （SRC） members with stud connectors after fire

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Frontiers of Structural and Civil Engineering 2014年第2期8卷 140-150页

作者： zihua zhang Junhua LI Lei zhang Kai YU College of Civil Engineering and Environment Ningbo University Ningbo 315211 China

Statically push-out tests of 20 steel reinforced concrete short columns （SRCSC） with stud connectors on the surface of shape steel after fire and two SRCSC under ambient temperature were carried out, in order to study the failure mode, load-slip relationship and the interfacial shear transfer of SRC members after fire. Experimental results show that the typical failure modes and load-slip curves of SRCSC after fire are almost the same as the case under ambient temperature. The interfacial shear transfer of SRCSC declines exponentially not only with the increase of the peak temperature the specimen experienced but also with the increase of the peak temperature duration. The interfacial shear transfer of the specimens with studs arranged at the steel web is much higher than those with studs arranged at the steel flange. Empirical formulas of SRCSC interfacial shear transfer after fire are proposed, and the calculated results generally agree well with the experimental results.

关键词： steel reinforced concrete （SRC） short column stud connector afcer fire interfacial shear transfer

The Static Solution for the Layered Piezoelectric Bounded Domain with Side Face Load by the Modified SBFEM

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Advances in Applied Mathematics and Mechanics 2018年第1期10卷 209-241页

作者： Shan Lu Jun Liu Gao Lin zihua zhang Pengchong zhang State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalianLiaoning 116024China School of Hydraulic Engineering Faculty of Infrastructure EngineeringDalian University of TechnologyDalianLiaoning 116024China Ocean Engineering Joint Research Center of DUT-UWA State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of TechnologyDalianLiaoning 116024China Faculty of Civil Engineering Ningbo University315211China

The static response of two-dimensional horizontal layered piezoelectric bounded domain with side face load was investigated.In this paper,the modified scaled boundary finite element method(SBFEM)is provided as an effective semi analytical methodology.The method is used to solve the static problem for the layered piezoelectric bounded domain.The scaling line definition extends the SBFEM to be more suitable for analyzing the multilayered piezoelectric bounded domain.It avoids the limitations of original SBFEM in modeling the horizontal layered bounded domain.The modified SBFEM governing equation with piezoelectric medium is derived by introducing Duality variable in the Hamilton system.This derivation technology makes the progress be concise.The novel displacement and electric governing equations of the modified SBFEM is given together by the first time.The node forces can be expressed as power exponent function with radial coordinate by introducing the auxiliary variable and using the eigenvalue decomposition.The novel modified SBFEM solution of layered bounded domain with piezoelectric medium is solved.The new power expansion function of layered piezoelectric medium with side face load is proposed.This technology significantly extends the application range of modified SBFEM.The novel treatment of side face load for the layered piezoelectric bounded domain is proposed.Numerical studies are conducted to demonstrate the accuracy of proposed technique in handling with the static problem of layered bounded domain with piezoelectric medium for side face load.The influence of the side face load type and depth are discussed in detail.

关键词： Modified scaled boundary finite element method piezoelectric medium side face load layered bounded domain

Experimental study of structural damage identification based on modal parameters and decay ratio of acceleration signals

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Frontiers of Structural and Civil Engineering 2011年第1期5卷 112-120页

作者： Zhigen WU Guohua LIU zihua zhang College of Civil Engineering and Architecture Zhejiang UniversityHangzhou 310027China

A novel damage assessment method based on the decay ratio of acceleration signals(DRAS)was proposed.Two experimental tests were used to show the efficiency.Three beams were gradually damaged,and then the changes of dynamic parameters were monitored from initial to failure state.In addition,a new method was compared with the linear modal-based damage assessment using wavelet transform(WT).The results clearly show that DRAS increases in linear elasticity state and microcrack propagation state,while DRAS decreases in macrocrack propagation state.Preliminary analysis was developed considering the beat phenomenon in the nonlinear state to explain the turn point of DRAS.With better sensibility of damage than modal parameters,probably DRAS is a promising damage indicator in damage assessment.

关键词： damage assessment decay ratio of acceleration signals(DRAS) wavelet transform(WT) modal analysis reinforced concrete beam beat phenomenon

河曲二人台国家级非物质文化遗产代表性传承人贾德义访谈

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文化遗产 2023年第3期 151-158页

作者：张子华榆林学院文学院陕西榆林719000

贾德义简介:山西河曲人,生于1940年,曾任河曲县文化局副局长、文化馆馆长,1987年评为副研究馆员。现任山西省民歌协会名誉主席、中国民间文艺家协会会员、中国民俗协会会员、中国歌谣协会会员。自上个世纪八十年代末,先后整理出版《河... 详细信息

贾德义简介:山西河曲人,生于1940年,曾任河曲县文化局副局长、文化馆馆长,1987年评为副研究馆员。现任山西省民歌协会名誉主席、中国民间文艺家协会会员、中国民俗协会会员、中国歌谣协会会员。自上个世纪八十年代末,先后整理出版《河曲二人台》《二人台》《西北风情歌--山曲儿精选》《山西二人台传统剧目全编》《山西二人台传统唱腔曲牌全编》《大河西口古渡/河曲民歌》《山西河曲传统二人台》《北方两句头》《过程--从吹鼓手到副教授》(未刊)九部民歌二人台著作,出版文学作品集《喇叭花》一部。2009年5月被认定为国家级非物质文化遗产项目“河曲二人台”代表性传承人。

关键词：代表性传承人副研究馆员中国歌谣中国民俗河曲民歌协会名誉主席副局长八十年代