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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

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一起330kV变电站跳闸事故原因分析

青海电力 2016年第4期35卷 60-62页

作者：王学斌赵世昌王轩汪凤月罗敏杨文丽杨嘉丛贵斌国网青海省电力公司电力科学研究院青海西宁810008

介绍一起330 kV变电站保护误动事故,通过技术分析及现场试验,指出故障合并单元FPGA芯片短暂工作异常引起插值时刻出错,装置输出波形畸变导致事故发生,并提出建议,以避免相同事故再次发生。

关键词：合并单元波形畸变温度变化试验防范措施

Free vibration analysis of functionally graded material beams based on Levinson beam theory

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Applied Mathematics and Mechanics(English Edition) 2016年第7期37卷 861-878页

作者： xuan wang Shirong LI School of Hydraulic Energy and Power Engineering Yangzhou University School of Civil Science and Engineering Yangzhou University

Free vibration response of functionally graded material （FGM） beams is studied based on the Levinson beam theory （LBT）. Equations of motion of an FGM beam are derived by directly integrating the stress-form equations of elasticity along the beam depth with the inertial resultant forces related to the included coupling and higherorder shear strain. Assuming harmonic response, governing equations of the free vibration of the FGM beam are reduced to a standard system of second-order ordinary differential equations associated with boundary conditions in terms of shape functions related to axial and transverse displacements and the rotational angle. By a shooting method to solve the two-point boundary value problem of the three coupled ordinary differential equations, free vibration response of thick FGM beams is obtained numerically. Particularly, for a beam with simply supported edges, the natural frequency of an FGM Levinson beam is analytically derived in terms of the natural frequency of a corresponding homogenous Euler-Bernoulli beam. As the material properties are assumed to vary through the depth according to the power-law functions, the numerical results of frequencies are presented to examine the effects of the material gradient parameter, the length-to-depth ratio, and the boundary conditions on the vibration response.

关键词： functionally graded material (FGM) beam Levinson beam theory (LBT),free vibration shooting method natural frequency

利用原子在圆偏振激光场中的强场电离产生自旋极化电子

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原子与分子物理学报 2025年第3期42卷 101-109页

作者：王中元高轩鸿景文泉杜进旭赵松峰西北师范大学物理与电子工程学院兰州730070

圆偏振激光场中原子的非绝热强场电离为产生自旋极化电子提供了机会.我们应用这些解析电离速率公式[Ingo Barth and Olga Smirnova,***.A 88,013401(2013)]更系统地研究了通过Kr和Xe原子在右旋圆偏振激光脉冲中的强场电离产生自旋极化电... 详细信息

圆偏振激光场中原子的非绝热强场电离为产生自旋极化电子提供了机会.我们应用这些解析电离速率公式[Ingo Barth and Olga Smirnova,***.A 88,013401(2013)]更系统地研究了通过Kr和Xe原子在右旋圆偏振激光脉冲中的强场电离产生自旋极化电子,并证实了不同自旋态的光电子能量分布有很大差异、电子的自旋极化敏感地依赖于光电子能量.另外,在光电子能谱的低能部分其自旋极化可以达到100%,并且通过调节激光强度和频率可以很好地控制能量积分的自旋极化.

关键词：自旋极化电子非绝热强场电离右旋圆偏振激光场

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Prediction and optimization of flue pressure in sintering process based on SHAP

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 346-359页

作者： Mingyu wang Jue Tang Mansheng Chu Quan Shi Zhen Zhang School of Metallurgy Northeastern UniversityShenyang 110819China Liaoning Low-Carbon Steelmaking Technology Engineering Research Center Northeastern UniversityShenyang 110819China Engineering Research Center of Frontier Technologies for Low-Carbon Steelmaking(Ministry of Education) Shenyang 110819China

Sinter is the core raw material for blast *** pressure,which is an important state parameter,affects sinter *** this paper,flue pressure prediction and optimization were studied based on the shapley additive explanation(SHAP)to predict the flue pressure and take targeted adjustment ***,the sintering process data were collected and processed.A flue pressure prediction model was then constructed after comparing different feature selection methods and model algorithms using SHAP+extremely random-ized trees(ET).The prediction accuracy of the model within the error range of±0.25 kPa was 92.63%.SHAP analysis was employed to improve the interpretability of the prediction *** effects of various sintering operation parameters on flue pressure,the relation-ship between the numerical range of key operation parameters and flue pressure,the effect of operation parameter combinations on flue pressure,and the prediction process of the flue pressure prediction model on a single sample were analyzed.A flue pressure optimization module was also constructed and analyzed when the prediction satisfied the judgment *** operating parameter combination was then *** flue pressure was increased by 5.87%during the verification process,achieving a good optimization effect.

关键词： sintering process flue pressure shapley additive explanation prediction optimization

Effects of MCI-186 on intracellular calcium ion concentration and membrane fluidity of hippocampal neurons in a rat model of Alzheimer's disease

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Neural Regeneration Research 2011年第29期6卷 2245-2250页

作者： Ming Yu Lei Qin zhao wang Xiaohong Lu Ying Zhu Wenhui Leng xuan wang Department of Neurology Affiliated Hospital of Jiangsu University Zhenjiang 212001 Jiangsu Province China Department of Preventive Medicine Nanjing University of Chinese Medicine Nanjing 210046 Jiangsu Province China Department of Biochemistry Basic Medical College of Jiamusi University Jiamusi 154007 Heilongjiang Province China Department of Neurology Affiliated First Hospital of Jiamusi University Jiamusi 154002 Heilongjiang Province China

The present study observed the effects of MCI-186 on the intracellular calcium ion concentration （[Ca2＋]i） and membrane fluidity of hippocampal neurons in Alzheimer＇s disease （AD） model rats to validate the neuroprotective effects of MCI-186. Compared with normal and sham-operated rats, the escape latency was obviously prolonged, spanning platform times were obviously reduced, [Ca2＋]i was increased, and microviscosity η value was increased in AD rats. MCI-186 at 0.5 mg/mL and 0.2 mg/mL obviously shortened escape latency, increased spanning platform times and decreased [Ca2＋]i and microviscosity η values in AD rats at 7 and 17 days after induction of the model. The differences in the above-mentioned indices between normal and MCI-186-treated rats were statistically significant. MCI-186 at 0.2 mg/mL yielded better curative effects than 0.5 mg/mL MCI-186. These findings suggest that MCI-186 improves learning and memory abilities in AD rats by decreasing [Ca2＋]i and increasing membrane fluidity of hippocampal neurons.

关键词： MCI-186 Alzheimer's disease learning memory calcium ion neurodegenerative diseases neural regeneration

Preparation and applications of calcium ferrite as a functional material:A review

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 292-310页

作者： Xiuli Han Bowen Duan Lei Liu Shilong Fang Weiwei wang College of Mining Engineering North China University of Science and TechnologyTangshan 063210China Collaborative Innovation Center of Green Development and Ecological Restoration of Mineral Resources of Hebei Province Tangshan 063210China Key Laboratory of Mining Development and Security Technology of Hebei Province Tangshan 063210China

Calcium ferrite(CF)is recognized as a potential green and efficient functional material because of its advantages of magnetism,electrochemistry,catalysis,and biocompatibility in the fields of materials chemistry,environmental engineering,and ***-fore,the obtained research results need to be systematically summarized,and new perspectives on CF and its composite materials need to be *** on the presented studies of CF and its composite materials,the types and structures of the crystal are *** addition,the current application technologies and theoretical mechanisms with various properties in different fields are ***,the various preparation methods of CF and its composite materials are elaborated in *** importantly,the advantages and disadvantages of the synthesis methods of CF and its composite materials are discussed,and the existing problems and emerging challenges in practical production are ***,the key future research directions of CF and its composite materials have been prospected from the potential application technologies to provide references for its synthesis and efficient utilization.

关键词： calcium ferrite mineral functional materials preparation application perspectives

Incipient motion of sediment in presence of submerged flexible vegetation

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Water Science and Engineering 2015年第1期8卷 63-67页

作者： Hao wang Hong-wu Tang Han-qing zhao xuan-yu zhao Sheng-qi Lü State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University

The presence of submerged vegetation on river beds can change the water flow structure and alter the state of sediment motion. In this study, the incipient motion of sediment in the presence of submerged flexible vegetation in open channels was investigated in a laboratory experiment. The vegetation was simulated with flexible rubber cylinders arranged in parallel arrays. The effect of the vegetation density, water depth, and sediment grain size on the incipient motion was investigated. The experimental results indicate that the incipient motion velocity of sediment increases as the vegetation density decreases and the water depth and sediment grain size increase. With flexible plants, the incipient motion velocity of sediment is lower than it is without vegetation, and is larger than it is with rigid vegetation. A general incipient motion velocity equation was derived, which can be applied to both flexible and rigid vegetation conditions.

关键词： Sediment incipient motion Submerged flexible vegetation Open channel Experimentation Sediment grain size Water depth

Analysis and Numerical Simulation of Rolling Contact between Sphere and Cone

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Chinese Journal of Mechanical Engineering 2015年第3期28卷 521-529页

作者： zhao Yanling XIA Chengtao wang Hongbo xuan Jiaping XIANG Jingzhong LIU Xianli SU Xiangguo School of Mechanical and Power Engineering Harbin University of Science and Technology Shenyang Aerospace Mitsubishi Motors Engine Manufacturing Co. Ltd

In non-conforming rolling contact, the contact stress is highly concentrated in the contact area. However, there are some limitations of the special contact model and stress model used for the theoretical study of the phenomenon, and this has prevented in-depth analysis of the associated friction, wear, and failure. This paper is particularly aimed at investigating the area of rolling contact between a sphere and a cone, for which purpose the boundary is determined by the Hertz theory and the geometries of the non-conforming surfaces. The phenomenon of stick-slip contact is observed to occur in the contact area under the condition of no-full-slip（Q 〈 μ·P）. Using the two-dimensional rolling contact theory developed by CARTER, the relative positions of the stick and slip regions and the distribution of the tangential force over the contact area are analyzed. Furthermore, each stress component is calculated based on the Mc Ewen theory and the idea of narrow band. The stress equations for the three-dimensional rolling contact between the sphere and the cone are obtained by the principle of superposition, and are used to perform some numerical simulations. The results show that the stress components have a large gradient along the boundary between the stick and slip regions, and that the maximum stress is inversely proportional to the contact coefficient and proportional to the friction coefficient. A new method for investigating the stress during non-classical three-dimensional rolling contact is proposed as a theoretical foundation for the analysis of the associated friction, wear, and failure.

关键词： tractive rolling Hertz theory stick-slip contact contact area contact stress