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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 179-196页

作者： Yali zhang Yueting ZHOU shenghu DING School of Mathematics and Statistics Ningxia UniversityYinchuan 750021China School of Aerospace Engineering and Applied Mechanics Tongji UniversityShanghai 200092China

Understanding and characterizing rough contact and wavy surfaces are essential for developing effective strategies to mitigate wear,optimize lubrication,and enhance the overall performance and durability of mechanical *** sliding friction contact problem between a thermoelectric(TE)half-plane and a rigid solid with a periodic wavy surface is the focus of this *** simplify the problem,we utilize mixed boundary conditions,leading to a set of singular integral equations(SIEs)with the Hilbert *** analytical solutions for the energy flux and electric current density are obtained by the variable transform method in the context of the electric and temperature *** contact problem for the elastic field is transformed into the second-kind SIE and solved by the Jacobi ***,the smoothness of the wavy contact surface ensures that there are no singularities in the surface contact stress,and ensures that it remains free at the contact *** on the plane strain theory of elasticity,the analysis primarily examines the correlation between the applied load and the effective contact *** distribution of the normal stress on the surface with or without TE loads is discussed in detail for various friction ***,the obtained results indicate that the in-plane stress decreases behind the trailing edge,while it increases ahead of the trailing edge when subjected to TE loads.

关键词： wavy surface periodic contact thermoelectric(TE)material Hilbert integral kernel

我国微生物农药环境风险评价标准体系构建方法与内容解析

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世界农药 2024年第1期46卷 14-22页

作者：卜元卿周蓉袁善奎虞悦张圣虎戴传超蓝帅生态环境部南京环境科学研究所南京210042 南京信息工程大学江苏省大气环境与装备技术协同创新中心南京210044 农业农村部农药检定所北京100125 南京师范大学生命科学学院南京210023

微生物农药作为最具潜力和价值的化学农药替代产品,开发应用前景广阔,但微生物农药进入环境后,在杀灭靶标生物的同时,对环境非靶标生物和人类健康也存在潜在风险。针对我国微生物农药环境安全管理的迫切需求,以风险控制为指导思想,通过... 详细信息

微生物农药作为最具潜力和价值的化学农药替代产品,开发应用前景广阔,但微生物农药进入环境后,在杀灭靶标生物的同时,对环境非靶标生物和人类健康也存在潜在风险。针对我国微生物农药环境安全管理的迫切需求,以风险控制为指导思想,通过开展相应的标准技术方法研究,构建了我国微生物农药环境风险评价标准体系,涵盖环境生物毒性评价和环境繁衍能力评价,以及基于2者的环境风险评估,拟填补我国微生物农药环境风险管理技术标准空白,对防控微生物农药环境风险,保护生态环境,促进微生物农药产业的健康发展具有重要意义。

关键词：微生物农药标准体系环境毒性评价环境增殖环境风险评估

Interface Behavior of Copper and Steel by Plasma-MIG Hybrid Arc Welding

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Acta Metallurgica Sinica(English Letters) 2013年第3期26卷 328-332页

作者： Tao YANG Hongming GAO shenghu zhang Lin WU State Key Laboratory of Advanced Welding and Joining Harbin Institute of Technology

Plasma-MIG hybrid arc welding is a hybrid heating source welding method which is composed of plasma arc and MIG arc. During Plasma-MIG hybrid arc welding process, the interface behavior of copper and steel dissimilar alloy is investigated. The results show that electromagnetic stirring effect decreases and the heat input increases with the increase of outer plasma current in the hybrid arc welding process. The interface diffusion and interface thickness is controlled by the tradeoff of electromagnetic stirring effect degradation and heat input increase. The interface diffusion and interface thickness are controlled by decreasing the electromagnetic stirring force and increasing the heat input with the increase of plasma current in Cu/Fe plasma-MIG hybrid arc welding process.

关键词： Plasma-MIG hybrid arc Copper-steel dissimilar alloy Interface behavior

Stereospecific Assembly of Trisubstituted Alkenes via Photoinduced Nitrogen-Centered Radical-Triggered C—C Bond Cleavage/Functionalization of Oxime Esters

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Chinese Journal of Chemistry 2024年第12期42卷 1399-1406页

作者： Yu Bao Zhi-Jie Song Jin-Long Dai shenghu Yan Yue zhang Jia-Yin Wang Guigen Li School of Pharmacy Changzhou UniversityChangzhouJiangsu 213164China Department of Chemistry and Biochemistry Texas Tech University79409USA

Comprehensive Summary A general and convenient photoredox-catalyzed acylation and alkylcyanation of MBH acetates has been established,enabling the assembly of the C(sp2)–C(sp3)bond by a nitrogen-centered radical strategy for the synthesis of trisubstituted alkenes in moderate to excellent chemical yields(48 examples in total).The reaction of MBH acetates with acyl(indanone)oxime esters afforded trisubstituted alkenes containing 1,4-dicarbonyl ***,the use of Eosin Y as a photocatalyst in the catalytic system resulted in the formation of distal cyano group-anchored trisubstituted alkenes via deconstructive functionalization of cycloketone oxime ***,these resulting 1,4-dicarbonyl compounds could be applied to late-stage transformations,providing important methods for the synthesis of dihydropyridazin-3(2H)-one.

关键词： Photocatalysis Radical reactions MBH acetates Oxime esters Stereoselectivity Acylation Alkylation Green chemistry

Design of an RFQ for direct plasma injection scheme

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Nuclear Science and Techniques 2009年第5期20卷 277-280页

作者： zhang Zhouli R.A. Jameson ZHAO Hongwei XU Zhe LIU Yong zhang shenghu zhang Cong SUN Liepeng MEI Lirong SHEN Xiaokang Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Institut far Angewandte Physik Goethe Universityat. Frankfurt D60438 Frankfurt-am-Main Germany

A high current radio frequency quadrupole (RFQ) is being studied at the Institute of Modern Physics, Chinese Academy of Sciences (IMP, CAS) for the direct plasma injection scheme (DPIS). Because of the strong space charge of beams from laser ion source, the beam dynamics design of the RFQ has been carried out with a new code, which can deal with space charge effectively. The design of the RFQ structure is performed with an electromagnetic simulation code and the determination of parameters of the structure has been done to maximize the shunt impedance when the frequency is kept fixed. The influences of dipole mode effect and flatness on beams were also discussed.

关键词：无电通信 RFQ IMP CAS

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基于SPOC+直播的混合式教学实践与研究

大学教育 2022年第2期 29-32页

作者：张胜虎江西师范大学数学与统计学院江西南昌330022

在信息化时代,基于SPOC的混合式教学模式由于融合了MOOC和传统课堂的优点,成为高校教学改革的趋势。在疫情期间,基于SPOC+直播的混合式教学模式受到广大教师的关注。文章以概率论与数理统计为例,叙述了SPOC+直播的教学实践,包括教学实... 详细信息

在信息化时代,基于SPOC的混合式教学模式由于融合了MOOC和传统课堂的优点,成为高校教学改革的趋势。在疫情期间,基于SPOC+直播的混合式教学模式受到广大教师的关注。文章以概率论与数理统计为例,叙述了SPOC+直播的教学实践,包括教学实施过程、引入统计软件教学尝试及考试成绩分析。实践表明,基于SPOC+直播的教学模式相对于SPOC教学模式来说有自身的优势,但也存在不足,而考试成绩方面则不存在明显差异。

关键词：教学模式 SPOC 直播混合式教学

6-8 Volume Production of HWR010 Cavities in IMP

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IMP & HIRFL Annual Report 2015年第1期 269-270页

作者： Yue Weiming zhang shenghu He Yuan Linac Group 不详

The development of the Half Wave Resonator (HWR010) is based on the China ADS project. The HWR010 operates at 162.5 MHz and can provide more than 0.78 MV of accelerating voltage per cavity for proton with opt=0.10. The goal of the RF properties is to get a lower heat load and a higher accelerating gradient, which are determined by a higher R/Q0 and lower peak surface fields (Bpk/Eacc and Epk/Eacc). In order to optimize the HWR geometry parameters, CST-MWS is used to conduct the RF simulation. The optimized RF parameters are show in Table 1.

关键词： HWR010 Cavities IMP

6-7 Mechanical Design and Fabrication of 162.5 MHz Buncher for C-ADS Injector II

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IMP & HIRFL Annual Report 2014年第1期 256-257页

作者： Niu Haihua zhang Bin Yuan Chenzhang Huang Shichun Jia Huan zhang shenghu 不详

Two room temperature quarter wave resonator（QWR）buncher cavities with frequency of 162.5 MHz havebeen designed as parts of the medium energy beam transport line（MEBT1）for injectorⅡin China AcceleratorDriven Sub-critical System (C-ADS) project in order to focus the beam longitudinally, thus keeping the bunchlength and matching the beam to the acceptance of the superconducting *** is one of major equipments in MEBT1. Fig. 1 shows the layout of the MEBT1. Its structure directlyaffects the performance of MEBT1. Buncher cavity takes an open-ended quarter-wavelength coaxial line cylindertype structure, the mechanical design of buncher cavity was done according to the physical design, adequate considerationought to be given to the factors of electromagnetic field distribution, power coupling, frequency tuning,cavity cooling and manufacturing, and so on.

关键词： Mechanical Design Fabrication

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受载空心柱下多孔半空间的接触分析

力学学报 2024年第8期56卷 2338-2350页

作者：杨勇林张亚莉马海亮丁生虎李星汪文帅宁夏大学数学统计学院宁夏数学基础学科研究中心

多孔结构具有诸多优良特性被广泛应用于航空航天、生物医疗以及各种工程装备中,而空心柱具有独特的结构常被用于承担结构载荷.因此,研究空心柱与多孔半空间的接触问题显得尤为重要.文章运用Hankel变换将轴对称接触问题转化为积分方程的... 详细信息

多孔结构具有诸多优良特性被广泛应用于航空航天、生物医疗以及各种工程装备中,而空心柱具有独特的结构常被用于承担结构载荷.因此,研究空心柱与多孔半空间的接触问题显得尤为重要.文章运用Hankel变换将轴对称接触问题转化为积分方程的求解问题,推导出表面接触应力和位移的精确表达式.发展了高斯-切比雪夫结合乘积型Bessel函数的无穷积分的数值求解方法,并退化对比验证了方法的正确性,结果表明该方法在奇异值处的计算精度和效果更佳.数值分析了表面接触应力随泊松比、孔隙率、力载荷、内径、壁厚(空心圆柱)和半径(碗形抛物柱)的变化情况,并给出了位移随孔隙率、内径、壁厚、半径及深度的变化情况.研究结果表明基体的接触区域中心产生明显的叠加变形,并且接触区域外侧的奇异性要高于内侧,所以外侧更有可能是裂纹的起始位置.此外,在较小的内径下,当空心柱壁厚与实心柱半径一致时,空心柱比实心柱所导致的基体接触区域外边缘的应力奇异性小1倍以上,并且随着孔隙率的增大该比值降低;当空心柱外径与实心柱半径一致时,空心柱比实心柱所导致的基体接触区域外边缘的应力奇异性大1倍以上,并且在大孔隙下该比值更大.研究结果对多孔材料的设计和应用具有重要的指导意义.

关键词：空心柱多孔材料轴对称接触 micro-dilatation理论积分方程方法