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High Voltage 2024年第1期9卷 94-104页

作者： Xu Yang Hong zhao Chengcheng Zhang Chunyang Li xindong zhao Jiaming Yang Xuan Wang Key Laboratory of Engineering Dielectrics and Its Application Harbin University of Science and TechnologyHarbinChina

To enhance the DC electrical performance of cross-linked polyethylene(XLPE),the graftable antioxidant methacrylic acid 2-hydroxy-3-(4-anilinoanilino)propyl ester(GA),which contains carbonyl and amino groups,and the crosslinking coagent trimethylolpropane trimethacrylate(TMPTMA),which contains carbonyl groups,are individually or co-grafted onto *** slightly higher deep trap density introduced by higher grafting concentration of TMPTMA results in more significant suppression effect of conductance current and enhanced breakdown strength at a lower temperature,while the suppression effect for the conductance current at 90°C becomes weakened due to limited trap ***,the deeper energy level introduced by GA suppresses the conductance current and improves the electrical strength of XLPE at 90°C more *** co-grafting,the conductance current of XLPE in a wide range temperature can be significantly reduced,especially for the temperature dependence of conductance current,which is beneficial to suppress the field strength *** results of thermally stimulated current and molecular simulation show that the polar groups of two monomers introduce deep charge traps in *** co-grafting system ensures the rationality of the crosslinking reaction kinetics and does not affect the cable manufacturing.

关键词： crosslinking electrical grafting

金融发展在收入不平等与经济增长关系中的作用

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社会科学战线 2024年第3期345卷 68-81页

作者：赵昕东沈承放华侨大学统计学院福建厦门361021 华侨大学经济与金融学院福建泉州362021

收入不平等—经济增长理论以信贷约束为假设条件,因此在不考虑金融发展水平的条件下分析收入不平等与经济增长关系的结果是不可信的。文章基于中国2008—2019年省际面板数据,探讨了金融发展对收入不平等与经济增长关系的影响。研究发现... 详细信息

收入不平等—经济增长理论以信贷约束为假设条件,因此在不考虑金融发展水平的条件下分析收入不平等与经济增长关系的结果是不可信的。文章基于中国2008—2019年省际面板数据,探讨了金融发展对收入不平等与经济增长关系的影响。研究发现:第一,在控制金融发展水平下,收入不平等对经济增长具有显著负向影响;第二,金融发展对收入不平等与经济增长关系的直接影响效应总体是模糊的,能够削弱收入不平等对人力资本投资的负向影响,增强收入不平等对创新投资的正向影响,但削弱收入不平等对物质资本投资的正向影响;第三,随着经济发展水平的提高,金融业市场化反而对收入不平等对经济增长的负向效应具有增强作用。此外,金融发展能够显著削弱城乡间收入不平等对经济增长的负向影响。最后,文章根据研究结果提出相应的对策建议。

关键词：金融发展收入不平等经济增长物质资本人力资本创新

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中小银行规模、地方政府负债与创业活力

南京社会科学 2024年第4期 36-46,82页

作者：赵昕东吴炜聪华侨大学数量经济研究院福建厦门361000

提高创业活力已经成为促进经济高质量发展的重要推力。本文利用2005—2019年全国29个省市自治区的面板数据,用地方商业银行以及股份制商业银行资产总值占银行业资产总值的比重反映中小银行规模,研究其对地区创业活力的影响。结果发现,... 详细信息

提高创业活力已经成为促进经济高质量发展的重要推力。本文利用2005—2019年全国29个省市自治区的面板数据,用地方商业银行以及股份制商业银行资产总值占银行业资产总值的比重反映中小银行规模,研究其对地区创业活力的影响。结果发现,中小银行规模扩大可以有效促进创业活力;地方商业银行在地方政府的发展偏好影响下,可以通过提高信贷可得性促进创业,而股份制商业银行因为市场化程度高,只能通过提升银行竞争力促进创业。异质性分析发现,中小银行规模扩大对生存型创业的促进作用大于机会型创业。此外,在放开中小银行分支机构数量限制后,中小银行规模扩大对创业将产生显著的促进作用,但是存在着地方政府负债会挤出地方商业银行规模扩大产生的创业促进效应等。为此,应适当放宽中小银行的准入原则,促进银行业的公平有序竞争,支持金融服务较弱地区的中小银行发展,并严格控制地方政府债务规模,遏制隐性债务,健全地方政府举债融资机制。

关键词：中小银行规模创业活力地方政府负债信贷可得性银行竞争

极性分子的结构异同性对接枝改性交联聚乙烯材料直流电性能的影响

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电工技术学报 2024年第1期39卷 34-44页

作者：王凯赵新东郑海峰杨旭邵满志赵洪王暄工程电介质及其应用技术教育部重点实验室(哈尔滨理工大学) 哈尔滨150080 哈尔滨哈普电气技术有限责任公司哈尔滨150040

为改善高压直流电缆运行过程中绝缘层材料的电导率对温度与电场强度敏感性所导致的电场反转问题,以及直流高压长时间作用下的空间电荷积聚现象,该文采用极性基团接枝改性的方式提升交联聚乙烯(XLPE)材料的直流电性能。由于接枝单体一般... 详细信息

为改善高压直流电缆运行过程中绝缘层材料的电导率对温度与电场强度敏感性所导致的电场反转问题,以及直流高压长时间作用下的空间电荷积聚现象,该文采用极性基团接枝改性的方式提升交联聚乙烯(XLPE)材料的直流电性能。由于接枝单体一般为沸点较低的极性小分子化合物,为避免材料在接枝过程中单体的气化损失,首先通过平行双螺杆挤出机配合低温高压计量泵装置实现熔融接枝反应。将丙烯酸酯类小分子化合物(丙烯酸甲酯(MA)、丙烯酸丁酯(BA)、甲基丙烯酸甲酯(MMA))分别预先接枝到低密度聚乙烯(LDPE)大分子链上制备接枝材料,通过红外光谱测试分析得出接枝单体皆成功接枝到LDPE大分子链上,熔融指数与凝胶含量测定表明材料的流变性能并未发生显著改变,X射线衍射测试与扫描电子显微镜观测发现接枝改性材料的结晶特性保持与基础树脂相似。进一步对三种接枝母料按一定比例稀释并完成交联过程,通过变温直流电导测试发现三种接枝改性材料的电导率-温度敏感性均出现不同程度的下降,综合高温空间电荷测试可以得出,接枝MA的XLPE材料电导率-温度敏感性下降幅度最大、空间电荷分布特性优异;结合第一性原理仿真计算可以进一步得到,三种接枝单体改性XLPE模型的陷阱能级较为一致,其直流电性能的改善效果与接枝单体的静电势分布存在显著关联。

关键词：交联聚乙烯接枝改性丙烯酸酯电导率-温度敏感性静电势分布

Degree of bending of concrete-filled rectangular hollow section K-joints under balanced-axial loadings

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Frontiers of Structural and Civil Engineering 2022年第4期16卷 461-477页

作者： Rui zhao Yongjian LIU Lei JIANG Yisheng FU Yadong zhao xindong zhao School of Highway Chang’an UniversityXi’an 710064China Research Center of Highway Large Structure Engineering on Safety of Ministry of Education Xi’an 710064China

It has been found that the fatigue life of tubular joints is not only determined by the hot spot stress,but also by the stress distribution through the tube thickness represented as the degree of bending(DoB).Consequently,the DoB value should be determined to improve the accuracy of fatigue assessment for both stress-life curve and fracture mechanics ***,no DoB parametric formula is available for concrete-filled rectangular hollow section(CFRHS)K-joints,despite their wide use in bridge ***,a robust finite element(FE)analysis was carried out to calculate the DoB of CFRHS K-joints under balanced-axial *** FE model was developed and verified against a test result to ensure accuracy.A comprehensive parametric study including 190 models,was conducted to establish the relationships between the DoBs and four specific *** on the numerical results,design equations to predict DoBs for CFRHS K-joints were proposed through multiple regression analysis.A reduction of 37.17%was discovered in the DoB,resulting in a decrease of 66.85%in the fatigue ***,the CFRHS K-joints with same hot spot stresses,may have completely different fatigue lives due to the different DoBs.

关键词： fatigue assessment K-joint design equations degree of bending fracture mechanics

Structural damage assessment using improved Dempster-Shafer data fusion algorithm

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Earthquake Engineering and Engineering Vibration 2019年第2期18卷 395-408页

作者： Ding Yijie Yao Xiaofei Wang Sheliang zhao xindong School of Civil Engineering Xi'an Univ.of Arch.& Tech. CCCC First Highway Consultants Co. Ltd.

As an efficient tool in handling uncertain issues, Dempster-Shafer evidence theory has been increasingly used in structural health monitoring and damage detection. In applications, however, Dempster-Shafer evidence theory sometimes leads to counter-intuitive results. In this study, a new fusion algorithm of evidence theory is put forward to address various counter-intuitive problems and manage the reliability difference of the evidence. The proposed algorithm comprises the following aspects:(1) Dempster's combination rule is generalized by introducing the concept of evidence ullage. The new rule allows classical Dempster's rule and can resolve counter-intuitive problems cause by evidence conflict and evidence compatibility;(2) a reliability assessing method based on a priori and posterior knowledge is proposed. Compared with conventional reliability assessment, the proposed method can reflect the actual evidence reliabilities and can efficiently reduce decision risk. Numerical examples confirm the validity and utility of the proposed algorithm. In addition, an experimental investigation on a spatial truss structure is carried out to illustrate the identified ability of the proposed approach. The results indicate that the fusion algorithm has no strict request on the accuracy and consistency of evidence sources and can efficiently enhance diagnostic accuracy.

关键词： Dempster-Shafer evidence theory damage detection evidence confl ict evidence reliability spatial truss structure

Optimisation method for carbon black distribution of polypropylene-based semi-conductive screen materials and its effect on charge emission behaviour at screen/insulation interface

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High Voltage 2023年第2期8卷 239-250页

作者： Jiaming Yang Rui Zhang Xu Yang Zhi Sun xindong zhao Hong zhao Xuan Wang Lin Li Heqian Liu Key Laboratory of Engineering Dielectrics and Its Application Harbin University of Science and TechnologyHarbinChina State Grid Heilongjiang Electric Power Company Limited Electric Power Research Institute State Grid Corporation of ChinaHarbinChina

The semi-conductive(SC)screen materials used in polypropylene(PP)-based cables are usually multi-component *** shows poor compatibility with carbon black(CB),and CB particles tend to disperse in the elastomer phase,which results in CB non-uniform dispersion in screen *** non-uniform distribution of CB will cause abnormal electric fields at the screen/insulation interface and affect insulation *** paper prepared modified PP grafted by molecule maleic anhydride,and four PP-based SC shielding materials were blended in combination with PP,PP-g-MAH,and thermoplastic elastomer(POE)as matrix *** CB distribution,electrical conductivity,and basic physical properties of the shielding material were *** screen materials were served as electrodes to test their effects on the space charge and conductivity characteristics of *** relationship between the macroscopic properties and the distribution characteristics of CB was *** show that the selective dispersion of CB in screen material was improved by PPg-MAH and the surface electric potential distribution was *** emission at the screen/insulation interface and conductivity can be reduced by homogenising the CB ***/PP-g-MAH/POE prepared in this paper exhibits relatively uniform CB distribution,which can reduce the charge emission from the screen/insulation interface.

关键词： insulation distribution interface

Research on the threshold effect of population aging on the industrial structure upgrading in China

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Chinese Journal of Population,Resources and Environment 2019年第1期17卷 87-100页

作者： Chengkun Liu Shuyu Li xindong zhao School of Economics and Finanee Huaqiao University Quanzhou China

This paper constructs coefficients of the integral and the internal structure upgrading in the secondary and tertiary industries, selects per capita real gross domestic product as a threshold variable and build panel threshold model according to inter-provincial panel data of China from 1998 to 2016. Results indicated that population aging has a double threshold effect on the integral industrial structure upgrading, whose influence increases first and then decreases, significantly promoting the upgrading process. As for internal structure, population aging has no significant threshold effect on the upgrading in the secondary industry, but exerts a single negative threshold effect in the tertiary industry. When economic development is under the threshold, its negative impact is greater. Further analysis also suggests that regional differences exist significantly in the threshold effect of population aging on the industrial structure upgrading.

关键词： Population aging industrial structure upgrading threshold effect

Improved Diurnal Cycle of Precipitation on Land in a Global Non-Hydrostatic Model Using a Revised NSAS Deep Convective Scheme

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Advances in Atmospheric Sciences 2024年第6期41卷 1217-1234页

作者： Yifan zhao xindong PENG Xiaohan LI Siyuan CHEN State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China University of Chinese Academy of Sciences Beijing 100049China CMA Earth System modeling and Prediction Centre Beijing 100081China 2035 Future Laboratory PIESAT Information Technology Co Ltd.Beijing 100195China

In relatively coarse-resolution atmospheric models,cumulus parameterization helps account for the effect of subgridscale convection,which produces supplemental rainfall to the grid-scale precipitation and impacts the diurnal cycle of *** this study,the diurnal cycle of precipitation was studied using the new simplified Arakawa-Schubert scheme in a global non-hydrostatic atmospheric model,i.e.,the Yin-Yang-grid Unified Model for the *** new diagnostic closures and a convective trigger function were suggested to emphasize the job of the cloud work function corresponding to the free tropospheric large-scale *** results of the 0.25-degree model in 3-month batched real-case simulations revealed an improvement in the diurnal precipitation variation by using a revised trigger function with an enhanced dynamical constraint on the convective initiation and a suitable threshold of the *** reducing the occurrence of convection during peak solar radiation hours,the revised scheme was shown to be effective in delaying the appearance of early-afternoon rainfall peaks over most land areas and accentuating the nocturnal peaks that were wrongly concealed by the more substantial afternoon *** addition,the revised scheme enhanced the simulation capability of the precipitation probability density function,such as increasing the extremely low-and high-intensity precipitation events and decreasing small and moderate rainfall events,which contributed to the reduction of precipitation bias over mid-latitude and tropical land areas.

关键词： cumulus parameterization diurnal cycle of precipitation large-scale dynamic forcing global non-hydrostatic atmospheric model performance verification

Dihydroartemisinin enhances cell apoptosis in diffuse large B cell lymphoma by inhibiting the STAT3 activity

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BIOCELL 2023年第5期47卷 1075-1083页

作者： ZHENG CAO CHUNXIAO ZHOU ZHIMIN WU CHUNYAN WU WEN ZHANG SHILV CHEN xindong zhao SHAOLING WU Qingdao University Qingdao266000China Department of Hematology The Affiliated HospitalQingdao UniversityQingdao266000China

Background:Dihydroartemisinin(DHA)is reported to be a potential anticancer agent,and the mechanisms underlying the effects of DHA on diffuse large B cell lymphoma however are still *** study aimed to assess the antitumor effect of DHA on diffuse large B cell lymphoma cells and to determine the potential underlying mechanisms of DHA-induced cell ***:Here,the Cell Counting Kit 8 assay was conducted to study cell *** performed Annexin V-FITC/propidium iodide staining,real-time polymerase chain reaction,and western blot analysis to analyze cell apoptosis and potential molecular ***:The results showed that DHA substantially suppressed cell proliferation and induced cell apoptosis in vitro in a time-and concentration-dependent ***,STAT3 activity could be inhibited after stimulation with ***:These results imply that the underlying anti-tumoral effect of DHA may increase apoptosis in diffuse large B cell lymphoma cells via the STAT3 signaling *** addition,DHA might be an effective drug for diffuse large B cell lymphoma therapy.

关键词： Diffuse large B cell lymphoma Dihydroartemisinin STAT3 Cell apoptosis