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风荷载作用下储罐罐壁的力学性能

黑龙江科技大学学报 2024年第05期34卷 694-699+716页

作者：周利剑董守业东北石油大学土木建筑工程学院

为研究大型钢制储罐在风荷载作用下的力学特性，借助有限元软件ABAQUS,建立了静力风荷载作用下储罐有限元模型，对比分析裸罐(不含抗风结构)与加强罐(含抗风结构)在风荷载作用下迎风面与侧风面罐壁的应力与变形结果，以及储液对储罐抗... 详细信息

为研究大型钢制储罐在风荷载作用下的力学特性，借助有限元软件ABAQUS,建立了静力风荷载作用下储罐有限元模型，对比分析裸罐(不含抗风结构)与加强罐(含抗风结构)在风荷载作用下迎风面与侧风面罐壁的应力与变形结果，以及储液对储罐抗风性能的影响。结果表明：迎风面罐壁受风压力作用，罐壁内凹，侧风面罐壁受风吸力影响，罐壁外凸；风荷载对空罐影响较大，抗风结构可以有效地减弱空罐状态下罐壁顶部的变形；充液状态下，风荷载对罐壁的作用效果不明显，在储液压力作用下罐壁最容易破坏的位置出现在距离罐底高度2.42 m处。

关键词：大型储罐风荷载抗风结构储液

消费者对桨板运动的空间感知与价值寻求:方法-目的链理论的应用

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中国体育科技 2024年第1期60卷 82-89页

作者：吕海龙廖力坚马培艳付庭如湖南师范大学湖南长沙410081 怀化学院湖南怀化418000 福建师范大学福建福州350117 湖南医药学院湖南怀化418000

通过方法-目的链理论模型探索消费者对桨板运动空间感知的心理结构与路径。研究发现,消费者对桨板运动存在3种基本的空间感知模式,其中,对优良、理想水域的空间属性感知是吸引消费者持续参与桨板活动的基本前置要素,对俱乐部服务内容的... 详细信息

通过方法-目的链理论模型探索消费者对桨板运动空间感知的心理结构与路径。研究发现,消费者对桨板运动存在3种基本的空间感知模式,其中,对优良、理想水域的空间属性感知是吸引消费者持续参与桨板活动的基本前置要素,对俱乐部服务内容的空间感知是桨板文化属性得以传播和延续的社会组织保障要素,对桨板运动中的社会活动空间感知则赋予了桨板运动空间特殊的社会文化符号意义。据此,桨板运动消费者形成了4种空间价值寻求,即享受生活、情感满足、社会交往和生态环境保护,用以充实自我、彰显社会文明和可持续发展的价值趋向。建议:优化桨板运动水域空间,提升俱乐部资质、服务质量,以实现桨板消费活动延续性;促进多业态融合,拓展桨板运动的社会空间,建立产品空间吸引力与地方自然生态、地方文化、个人身份认同等的紧密联系。

关键词：桨板消费者空间感知价值寻求方法-目的链

Finite p-groups with a minimal non-abelian subgroup of index p(Ⅲ)

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Science China Mathematics 2015年第4期58卷 763-780页

作者： QU HaiPeng XU MingYao AN lijian School of Mathematics and Computation Science Shanxi Normal University

This paper finishes the classification of three-generator finite p-groups G such that Φ(G) Z(G).This paper is a part of classification of finite p-groups with a minimal non-abelian subgroup of index p, and partly sol... 详细信息

关键词： characteristic matrix At-groups congruent sub-congruent quasi-congruent

Residue analysis and dissipation of a new fungicide 2-allylphenol in tomato

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Journal of Environmental Sciences 2005年第3期17卷 491-493页

作者： HUJi-ye ZHANGWen-ji lijian-zhong ResearchCenterforEeo-EvironmentalSciences ChineseAcademyofSciencesBeijing100085.China ScienceCollege ChinaAgriculturalUniversity.Beijiug100094China

The method of residue analysis of a new synthesized fungicide 2-allylphenol was studied by simulating the active compound structure in Gingko tree(Gingko biloba L.) and its dissipation rate and terminal residue levels in tomato under field condition. Residues of 2-allylphenol were extracted from tomato matrix with acetone, purified by liquid-liquid extraction and Florisil cartrieges, and then determined by HPLC with UV-detector. The minimum detectable amount of 2-allylphenol was 3×10 -9 g, the minimum detectable concentration of 2-allylphenol in the samples of tomato were 0.01 mg/kg. The ranges of average recoveries and coefficient variation of the method were 87.7%—90.2% and 1.25%—2.06%, respectively. The dissipation rate and terminal residue levels in tomato were determined with the method described above. The results showed that the half-life of 2-allylphenol in tomato was 6.37 d, and 2-allylphenol declined with 82.6% of the initial deposit remaining in tomato at harvest. The terminal residue levels in tomato were 0.15 mg/kg and 0.20 mg/kg following the recommended doses and time intervals.

关键词： fungicide 2-allylphenol residue analysis dissipation

Microstructure and Mechanical Properties of 06Cr13Ni4Mo Steel Treated by Quenching–Tempering–Partitioning Process

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Journal of Materials Science & Technology 2016年第2期32卷 189-193页

作者： Yuanyuan Song Jingping Cui lijian Rong Institute of Metal Research Chinese Academy of Sciences Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal Research Chinese Academy of Sciences

A heat treatment process, quenching-tempering-partitioning （Q-T-P）, has been applied to a low carbon martensitic stainless steel 06Crl3Ni4Mo. By using this process, ultrafine reversed austenite can be obtained at room temperature. The microstructures of the reversed austenite and the martensite matrix were characterized by transmission electron microscopy （TEM） and energy dispersive spectroscopy （EDS） in detail. The results show that the ultrafine reversed austenite is enriched in Ni resulting in the austenite stability at room temperature. Two new types of nano-scale carbide precipitates are found in the martensite matrix. Detailed analysis suggests that the two nano-scale precipitates can be identified as ω phase and λ phase carbides, respectively. The orientation relationship between the ω phase and matrix is [011]α [/[2110]ω and （211）α//（0110）ω, while that between the X phase precipitate and matrix is [011]α][[0001]λ and （200）α/（1210）λ. For the present steel, the ultrafine reversed austenite and carbide precipitates obtained by Q-T-P treatment provide a good combination of high strength and toughness.

关键词： Quenching-tempering-partitioning Martensitic stainless steel Microstructure Reversed austenite Carbide precipitates

Syntheses of Tetrahydropyrrolizino[2,1-c]quinoline Derivatives

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Chemical Research in Chinese Universities 2005年第4期21卷 460-462页

作者： SONGHong-rui WANGFei lijian ZHANGShou-fang SchoolofPharmaceuticalengineering ShenyangPharmaceuticalUniversityShenyang110016P.R.China

The three title compounds were prepared from 2-phenylaminomethyl-3H-1,2-dihydro-1-pyrrolizinols via an intramolecular Friedel-Crafts reaction. 2-Phenylaminomethyl-3H-1,2-dihydro-1-pyrrolizinols were prepared from 2-phenylaminomethyl-3H-1,2-dihydro-1-pyrrolizinones via reduction. The heterocyclic ring system of pyrrolizino[2,1-c]quinoline has not been found in literature.

关键词： Pyrrolizino[2,1-c]quinoline Synthesis Heterocycles

Microstructure and Mechanical Properties of Electron Beam Welded Alloy J75

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Journal of Materials Science & Technology 2014年第5期30卷 493-498页

作者： Shenghu Chen Mingjiu Zhao Hao Liang lijian Rong Institute of Metal Research Chinese Academy of Sciences Institute of System Engineering China Academy of Engineering and Physics

Microstructure and mechanical properties of electron beam post-weld aging treatment （PWAT） conditions. The results welded alloy J75 were studied under as-welded and showed that high-quality welds were produced by electron beam welding. Under as-welded condition, a fine dendritic structure consisting of gamma dendrite matrix and Laves phase was observed in the welds. Better mechanical properties were obtained in the weld zone than that of base metal because of the fine size of the dendritic structure. After PWAT, a discontinuous distribution of γ＇ particles existed in the dendritic structure. The presence of a γ＇ depletion zone in the dendrite core resulted in a significant degradation of mechanical properties of the weld.

关键词： Electron beam welding Alloy J75 Precipitation Mechanical properties

Overview of hydrogen-resistant alloys for high-pressure hydrogen environment:on the hydrogen energy structural materials

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Clean Energy 2023年第1期7卷 99-115页

作者： Jiaxing Liu Mingjiu Zhao lijian Rong Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China

With the progressive expansion of hydrogen fuel demand,hydrogen pipelines,hydrogen storage cylinders and hydrogen refuelling stations(HRSs)are the primary components of hydrogen energy systems that face high-pressure hydrogen *** embrittlement(HE)is a typical phenomenon in metallic materials,particularly in the high-pressure hydrogen environment,that causes loss of ductility and potentially catastrophic *** is associated with materials,the service environment and *** primary mechanisms for explaining the HE of materials are hydrogen-enhanced decohesion,hydrogen-induced phase transformation,hydrogen-enhanced local plasticity,adsorption-induced dislocation emission and hydrogen-enhanced strain-induced *** reduce the risk of HE for metallic structural materials used in hydrogen energy systems,it is crucial to reasonably select hydrogen-resistant materials for high-pressure hydrogen *** paper summarizes HE phenomena,mechanisms and current problems for the metallic structural materials of hydrogen energy systems.A research perspective is also proposed,mainly focusing on metal structural materials for hydrogen pipelines,hydrogen storage cylinders and hydrogen compressors in HRSs from an application perspective.

关键词： hydrogen energy hydrogen refuelling station hydrogen pipelines hydrogen storage cylinder hydrogen embrittlement hydrogen embrittlement mechanism

1990-2019年全球宫颈癌疾病负担分析

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中华肿瘤防治杂志 2024年第4期31卷 210-215页

作者：卫飞雪冯瑞梅高雪丁玲雷立健王彤山西医科大学公共卫生学院流行病学与卫生统计学教研室煤炭环境致病与防治教育部重点实验室山西太原030001

目的通过分析全球、各区域和不同国家近30年宫颈癌疾病负担的变化趋势,以识别在消除宫颈癌方面取得进展的国家以及需要进一步努力的国家和地区,从而为实现世界卫生组织(WHO)提出的消除宫颈癌的全球目标提供借鉴。方法采用线性回归模... 详细信息

目的通过分析全球、各区域和不同国家近30年宫颈癌疾病负担的变化趋势,以识别在消除宫颈癌方面取得进展的国家以及需要进一步努力的国家和地区,从而为实现世界卫生组织(WHO)提出的消除宫颈癌的全球目标提供借鉴。方法采用线性回归模型分析全球疾病负担2019数据库中1990-2019年全球、6个WHO分区以及204个国家宫颈癌发病、死亡及伤残调整生命年(DALY)的时间变化趋势。结果全球宫颈癌新发病例数从1990年的335 642例增长至2019年的565 541例,年增长率为2.3%,死亡病例数从184 527例增长至280 479例,年增长率为1.7%。1990-2019年全球和除西太平洋地区以外的WHO区域宫颈癌年龄标化发病率、标化死亡率和标化DALY率均呈降低趋势,年降低率为0.1%~1.2%。在204个国家中,过去30年有43个国家宫颈癌标化发病率和20个国家宫颈癌标化死亡率呈增长趋势,这些国家主要集中在非洲地区,尤其是撒哈拉以南地区。结论全球宫颈癌绝对负担的增加以及在非洲等部分国家标化发病率和死亡率的增加提示亟需在这些地区制定和实施相关政策,以提高疫苗接种率、宫颈癌筛查覆盖率以及宫颈病变的治疗率,从而尽快实现在全球范围内消除宫颈癌这一宏伟目标。

关键词：宫颈癌发病死亡伤残调整生命年时间趋势分析