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AZ31B镁合金连续铸轧板材搅拌摩擦搭焊接头组织研究

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热加工工艺 2024年第12期53卷 145-149,154页

作者：董芬李铁龙许宝卉王付杰运城学院机电工程系山西运城044000

对AZ31B镁合金连续铸轧板材进行搅拌头逆时针与顺时针相结合的二道搅拌摩擦搭接焊。经对其搭接接头横截面的焊缝宏观及不同部位微观组织对比来分析二道搅拌摩擦焊对焊接接头塑性组织及成形的影响。结果表明:焊核区等轴晶粒组织特别细小... 详细信息

对AZ31B镁合金连续铸轧板材进行搅拌头逆时针与顺时针相结合的二道搅拌摩擦搭接焊。经对其搭接接头横截面的焊缝宏观及不同部位微观组织对比来分析二道搅拌摩擦焊对焊接接头塑性组织及成形的影响。结果表明:焊核区等轴晶粒组织特别细小、均匀;过渡区晶粒组织大小起伏较大,略大于焊核,较小于母材组织;前进侧界面迁移呈现大弧度卷起,比较突兀与焊核隔断,形成钩状缺陷,而后退侧界面迁移线缓缓渗入中部焊核区,渐渐消失于焊核组织内;前进侧迁移线的成形特点相比于孔洞隧道缺陷,成为整个焊接接头最薄弱部分;前进侧界面迁移线边的组织融合影响了对焊接头的成形;二道搅拌摩擦搭接两次搅拌头旋转方向同为逆时针时,能得到表面良好、组织熔合紧密、强度较高接头;当搭接接头上板为后退侧时,与上板为前进侧相比,搭接接头能够承受更大剪切力。

关键词： AZ31B镁合金连铸板材搅拌摩擦搭接焊界面迁移

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基于气凝胶拉吊索防火护套隔热性能研究

山东交通科技 2024年第3期 41-44页

作者：王富颉杨圣洁王润建浙江嘉绍跨江大桥投资发展有限公司浙江绍兴312000 北京公科固桥技术有限公司北京100088

研究气凝胶拉吊索防火护套隔热性能,并利用有限元软件对气凝胶拉吊索防火护套模型进行数值分析。选取常用规格PES 7-121平行钢丝拉吊索作为研究对象,研究5种不同厚度防火护套在石油罐车火灾HCinc模型曲线中持续60 min的护套内侧温度变... 详细信息

研究气凝胶拉吊索防火护套隔热性能,并利用有限元软件对气凝胶拉吊索防火护套模型进行数值分析。选取常用规格PES 7-121平行钢丝拉吊索作为研究对象,研究5种不同厚度防火护套在石油罐车火灾HCinc模型曲线中持续60 min的护套内侧温度变化规律。研究结果表明,随着火灾作用持续时间的不断增加,防火护套升温曲线基本呈线性关系,气凝胶防火护套厚度对拉吊索隔热效果影响较大,当护套厚度大于12 mm时,护套隔热效果增加不明显,当火灾持续60 min时护套内侧温度为133.7℃,隔热效率为87.85%,大于温度防护目标值300℃时隔热效率为72.42%,满足防火隔热要求。

关键词：拉吊索防火护套气凝胶隔热性能

甘肃省高校田径教练员核心素养现状与提升路径研究

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冰雪体育创新研究 2024年第1期 61-63页

作者：王福杰杜红娟陇东学院教育与体育学院甘肃庆阳745000 兰州市七里河区华林路第一小学甘肃西峰745000

甘肃省高校田径教练员的核心素养对于培养优秀田径人才、推动田径事业的发展至关重要。该文以甘肃省高校田径教练员为研究对象,深入分析了其核心素养现状,探讨了提升路径。经研究发现,当前甘肃省高校田径教练员在专业知识、教学技能、... 详细信息

甘肃省高校田径教练员的核心素养对于培养优秀田径人才、推动田径事业的发展至关重要。该文以甘肃省高校田径教练员为研究对象,深入分析了其核心素养现状,探讨了提升路径。经研究发现,当前甘肃省高校田径教练员在专业知识、教学技能、领导力等方面存在一些不足。为了提升核心素养,该文提出了加强师资培训、优化教学方法、促进实践经验交流等多方面的建议,旨在为甘肃省高校田径教练员的进一步发展提供有益借鉴。

关键词：甘肃省高校田径教练员核心素养现状提升路径

维普期刊数据库博看期刊

改进混合粒子群算法求解带时间窗的无人机与车辆协同路径调度问题

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计算机应用研究 2024年第8期41卷 2336-2342页

作者：叶立威吴钧皓戚远航罗浩宇黄戈文王福杰电子科技大学中山学院计算机学院广东中山528402 广东工业大学自动化学院广州510006 嘉应学院信息网络中心广东梅州514015 东莞理工学院卓越工程师学院广东东莞523808

为提高物流配送效率,考虑时间窗、无人机换电以及无人机多点连续配送等因素,提出了一种带时间窗的车辆与无人机协同配送问题,并设计一种带局部搜索的混合粒子群算法进行求解。该算法以混合粒子群算法为核心,通过构建高效的编解码策略实... 详细信息

为提高物流配送效率,考虑时间窗、无人机换电以及无人机多点连续配送等因素,提出了一种带时间窗的车辆与无人机协同配送问题,并设计一种带局部搜索的混合粒子群算法进行求解。该算法以混合粒子群算法为核心,通过构建高效的编解码策略实现了问题解空间到算法搜索空间的转换。进一步,该算法融合单点插入策略、车辆更换策略、无人机更换策略组成局部搜索策略,以此提高算法寻优能力。实验结果表明:所提模型比纯车辆配送的模型效率更高,节省了31.51%的成本;所提算法优于四种对比算法,优化率最高达到82.08%。

关键词：无人机车辆调度粒子群时间窗车辆路径问题

Genesis and Accumulation of Paleo-Oil Reservoir in Dabei Area,Kuqa Depression,Northwest China:Implications for Tight-Gas Accumulation

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Journal of Earth Science 2024年第2期35卷 655-665页

作者： fujie Jiang Xiao Chen Pengwei wang Xinghe Shao Haijun Yang State Energy Center for Shale Oil Research and Development Beijing102206China National Key Laboratory of Oil and Gas Resources and Engineering Beijing102249China College of Geosciences China University of PetroleumBeijing102249China CNOOC International Ltd. Beijing100027China Research Institute of Petroleum Exploration&Production SINOPECBeijing100083China Research Institute of Petroleum Exploration and Development Tarim OilfieldPetroChinaKorla841000China

Paleo-oil reservoir is of great importance to understand hydrocarbon enrichment mechanism and hydrocarbon exploration potential,but is yet poorly investigated in Kuqa *** occurrence of the paleo-oil reservoir in Dabei area was proved by quantitative grain fluorescence(QGF)and fluid inclusion *** history of the paleo-oil reservoir was reconstructed through:(1)oil-source correlation;(2)time coupling of source rock maturation,porosity evolution and migration *** impact of paleo-oil reservoir on tight-gas accumulation was consequently *** suggest that considerable oil was accumulated in the K_(1)bs reservoir with paleo oil-water contact in Dabei 2 Well and Dabei 201 Well at 5800 and 6040 m,*** oil was primarily sourced from Triassic source rocks with Jurassic source rocks of secondary importance,which was at oil generation window(0.7%–1.1%Ro)during 9–6 and 7.5–5 Ma,*** occurrence of K_(1)bs tight reservoir(porosity<12%)was about 25 Ma,while faults and associated fractures at Kelasue structural belt were developed approximately from 8 to 3.5 ***,the tight oil accumulation was formed during 8–5 *** paleo-oil reservoir in Dabei 1 gas field was destroyed by the evaporation fractionation in later stage.

关键词： Paleo-oil reservoir Dabei area Kuqa Depression Northwest China petroleum geology

饱和土与结构动力相互作用的二维摩擦接触模型

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北方工业大学学报 2024年第2期36卷 66-76页

作者：宋佳沈浩浩王福杰尹智超商静怡北方工业大学土木工程学院

由于孔隙流体的存在，饱和土-结构的动力相互作用相比经典固-固接触的相互作用更加复杂，主要存在两类耦合问题：饱和土中的流-固耦合，以及结构与饱和土间的接触耦合。本文针对饱和土与结构间的动力接触摩擦效应问题，建立了可反映“粘... 详细信息

由于孔隙流体的存在，饱和土-结构的动力相互作用相比经典固-固接触的相互作用更加复杂，主要存在两类耦合问题：饱和土中的流-固耦合，以及结构与饱和土间的接触耦合。本文针对饱和土与结构间的动力接触摩擦效应问题，建立了可反映“粘结-滑移-分离”状态的饱和土与结构动力摩擦接触模型。该模型是由一系列“点-线”单元构成的接触界面，并基于摩尔库伦模型及有效应力原理，根据接触判别条件，分别从位移和孔压两方面建立不同接触状态下的接触控制方程，并通过挡土墙与饱和土的相互作用算例验证了该模型的正确性。最后，以大开地铁车站为工程背景，分析了考虑接触模型的饱和土与地下结构的动力响应，以及考虑接触模型的必要性。

关键词：摩擦接触饱和多孔介质饱和土-结构动力相互作用

Viral vectors as a novel tool for clinical and neuropsychiatric research applications

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General Psychiatry 2018年第5期31卷 100-108页

作者： Yao wang Zhiwei Hu Peijun Ju Shan Yin fujie wang Oudong Pan Jinghong Chen Research and development department OBiO Technology (Shanghai) Corp. Ltd. Marketing department OBiO Technology (Shanghai) Corp. Ltd. Shanghai Mental Health Center Shanghai Jiao Tong University School of Medicine Shanghai Key Laboratory of Psychotic Disorders

Background A viral vector is a genetically modified vector produced by genetic engineering. As pathogenic genes in the virus are completely or largely eliminated, it is safe to be widely used in multidisciplinary research fields for expressing genes, such as neuroscience, metabolism, oncology and so on. Neuroscience and psychiatry are the most closely related disciplines in either basic research or clinical research, but the application of viral vectors in neuropsychiatry has not received much attention or not been widely *** This article will focus on the application of viral vectors in basic and clinical neuropsychiatric *** By using viral vectors, scientists can perform neurological labelling, gene expression regulation and physiological manipulation for investigating phenomenon from molecular mechanisms to behaviours. At the same time, to treat mental or neurological disorders, viral vectors can be designed for gene therapy, which alter gene expression levels or repair mutated genes in the brains of *** Viral vectors play an important role in basic research and clinical applications. To further understand brain function and prevent mental and neurological diseases, we hypothesize that viral vectors could be used along with various advanced technologies, such as sequencing and high-throughput expression analysis in the neuroscience research field.

关键词： Methods By using viral vectors Neuroscience and psychiatry

Hatching and development of maize cyst nematode Heterodera zeae infecting different plant hosts

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Journal of Integrative Agriculture 2024年第5期23卷 1593-1603页

作者： Jiangkuan Cui Haohao Ren Bowang fujie Chang Xuehai Zhang Haoguang Meng Shijun Jiang Jihua Tang College of Plant Protection National Key Laboratory of Wheat and Maize Crop ScienceHenan Agricultural UniversityZhengzhou 450002China

The occurrence, distribution, and rapid molecular detection technology of Heterodera zeae Koshy et al. 1971, have been reported in China. We explored the biological characteristics of H. zeae sampled in Henan Province, China to understand its interaction with plants. Cysts and second-stage juveniles(J2s) were identified under an optical and scanning electron microscope, internal transcribed spacer(ITS) phylogenetic tree, and sequence characterized amplified region(SCAR)-PCR analyses. The optimum hatching temperatures of H. zeae were 30°C and 28°C, with cumulative hatching rates of 16.5 and 16.1%, respectively, at 30 days post-hatching(dph). The hatching rate of H. zeae eggs was improved by 20-and 50-time maize soil leachate and root juice, and 10-time root exudates. The hatching rate in 10-time root exudates was the highest(25.9%). The 10-time root exudates of maize and millet produced the highest hatching rate at 30 dph(25.9 and 22.9%, respectively), followed by wheat(19.9%), barley(18.3%), and rice(17.6%). Heterodera zeae developed faster in maize than in other crops. Fourth-stage juveniles(J4s) were detected in maize roots 8 days post-inoculation(dpi) at 28°C but not in other crops. Combined with hatching tests, the Huang–Huai–Hai summer maize region and the south and central-southwest mountainous maize areas are highly suitable for H. zeae in China. This is the first systematically study of the hatching and infection characteristics on different plant hosts of corn cyst nematode H. zeae in temperate regions. This study laid a theoretical foundation for the rapid spread and high environmental adaptability of corn cyst nematode.

关键词： crop host resistance Heterodera zeae incubation fluid maize cyst nematode nematode development nematodehatching

Impact of Pd single-site coordination structure on catalytic performance for semihydrogenation of acetylene

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Nano Research 2024年第9期17卷 8243-8249页

作者： Yu Zeng Minqi Xia fujie Gao Changkai Zhou Xueyi Cheng Liwei Liu Liu Jiao Qiang Wu Xizhang wang Lijun Yang Yining Fan Zheng Hu Key Laboratory of Mesoscopic Chemistry of MOE and Jiangsu Provincial Laboratory for Nanotechnology School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Semihydrogenation of trace acetylene in an ethylene gas stream is a vital step for the industrial production of polyethylene,in which Pd single-site catalysts(SSCs)have great ***,two Pd SSCs with different coordination structures are prepared on hierarchical nitrogen-doped carbon nanocages(hNCNC)by regulating the nitrogen species with or without using *** using dicyandiamide,the obtained Pd1-Ndicy/hNCNC SSC features the coordinated Pd by two pyridinic N and two pyrrolic N(PdN^(py)_(2)N^(pr)_(2)).Without using dicyandiamide,the obtained Pd1/hNCNC SSC features the coordinated Pd by pyridinic N and C(PdN^(py_(x)C_(4-x)),x=1-4).The former exhibits an 18-fold increase in catalytic activity compared to the *** results reveal the abundant unoccupied orbital states above the Fermi level of moiety,which can facilitate the activation of substrate molecules and dynamics of acetylene hydrogenation as supported by the combined theoretical and experimental *** addition,PdN^(py)_(2)N^(pr)_(2)the moiety presents a favorable desorption of ***,the Pd1-Ndicy/hNCNC SSC exhibits high C2H2 conversion(99%)and C2H4 selectivity(87%)at 160℃.This study demonstrates the impact of Pd single-site coordination structure on catalytic performance,which is significant for the rational design of advanced Pd SSCs on carbon-based supports.

关键词： coordination structure hierarchical nitrogen-doped carbon nanocages palladium semihydrogenation of acetylene singlesite catalysts