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Transactions of Nanjing University of Aeronautics and Astronautics 2024年第4期41卷 515-525页

作者： TANG Tianyi he Yijie WU Jiajun DONG Menglong WANG Gang NI Junfang School of Mechanical and Electrical Engineering Soochow UniversitySuzhou 215131P.R.China

This paper presents a method to study the free vibration of a plate with circular *** circular hole is regarded as a virtual small plate in which the mass density and Young's modulus are ***,the free vibration problem of the circular hole plate can be transformed into the free vibration problem of the equivalent rectangular plate with non-uniform *** model is derived from the spectral geometry method(SGM),and the displacement of the plate with circular holes is expanded by the modified Fourier *** springs are added to the boundary of the plate to simulate the boundary conditions of simply supported and fixed *** accuracy of this method is verified by comparison with the finite element calculation *** relationship between modal numerical solutions of plates with circular holes and boundary conditions and geometry of the plate is studied.

关键词： round hole plate spectral geometry method(SGM) energy method virtual spring

Development and application of coke oven gas spraying on sinter bed

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Journal of Iron and Steel Research International 2020年第6期27卷 617-623页

作者： he-ping Li Sheng-li Wu zhi-bin Hong heng Zhou Ming-yin Kou School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Ironmaking Plant Shanghai Meishan Iron and Steel Co.Ltd.Nanjing210039JiangsuChina

The Shanghai Meishan Iron and Steel Co., Ltd. has a large supply of coke oven gas (COG) and has the potential to develop and apply the spraying of COG on the surface of a sinter bed. The effects of the amount of COG, the spraying time, and the spraying distribution with the process on the quantity and quality indexes of sinter were investigated in the laboratory experi-ments. The results showed that the COG spraying can improve the sinter indexes to a large extent if appropriate parameters were used. It was found that an appropriate amount of COG, a relatively long spraying time, and a decreasing distribution of the COG amount with the spraying process all help to obtain a better performance for sinter quantity and quality indexes. When the COG spraying was applied to the No. 3 sintering machine, the sinter tumbler index increased by 0.45%, the overall finished product rate increased by 0.72%, the solid fuel consumption decreased by 4.06kg/t, the reducibility increased by 3.89%, and the cost of iron decreased by 5.29 CNY/t, and the CO2, SO2 and Nox emissions also decreased, thus proving the feasibility of this technology. Therefore, COG spraying provides a new way to improve sinter and also decrease the energy consumption and pollution.

关键词： Coke oven gas spraying Sinter index Spraying distribution High quality Low energy consumption Low pollution

Advances in the Study of Psychological Stress and Eating Behavior in Children and Adolescents

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Journal of Clinical and Nursing Research 2024年第7期8卷 191-195页

作者： Ting he Le Wang Sha Wang Nannan Ma Li Mei Mengdan Zheng Shaanxi Provincial People’s Hospital Children’s Hospital Xi’an 710000Shaanxi ProvinceChina

With the rapid development and change in society,children and adolescents are facing more and more psychological pressure,which comes not only from academic performance and interpersonal relationships but also from family environment,social expectations and other *** stress not only affects the mental health of children and adolescents but is also closely related to their eating ***,exploring the relationship between psychological stress and eating behaviors is of great significance in promoting the physical and mental health development of children and *** on this,the study reviewed the research progress on the relationship between psychological stress and eating behavior of children and adolescents in recent *** relationships between psychological stress and general eating behaviors,abnormal eating behaviors and eating disorders were successively reviewed,and the related physiological mechanisms were explored with a view to providing a scientific basis for mental health education and eating behavior intervention for children and adolescents.

关键词： Children Adolescents Psychological stress Eating behavior Research progress

Effects of oxygen content on the oxidation process of Si-containing steel during anisothermal heating

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International Journal of Minerals,Metallurgy and Materials 2018年第2期25卷 164-172页

作者： Qing Yuan Guang Xu Wei-cheng liang Bei he Ming-xing Zhou The State Key Laboratory of Refi'actories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081China Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081China

The oxidizing behavior of Si-containing steel was investigated in an O2 and N2 binary-component gas with oxygen contents ranging between 0.5 vol% and 4.0 vol% under anisothermal-oxidation conditions. A simultaneous thermal analyzer was employed to simulate the heating process of Si-containing steel in industrial reheating furnaces. The oxidation gas mixtures were introduced from the commencement of heating. The results show that the oxidizing rate remains constant in the isothermal holding process at high temperatures; therefore, the mass change versus time presents a linear law. A linear relation also exists between the oxidizing rate and the oxygen content. Using the linear regression equation, the oxidation rate at different oxygen contents can be predicted. In addition, the relationship between the total mass gain and the oxygen content is linear; thus, the total mass gain at oxygen contents between 0.5 vol%–4.0 vol% can be determined. These results enrich the theoretical studies of the oxidation process in Si-containing steels.

关键词： oxidation oxygen content oxidation rate Si-containing steel fayalite anisothermal heating

聚α-烯烃合成基础油分子结构与性能关系研究进展

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石油学报（石油加工） 2024年第1期40卷 266-276页

作者：何垒垒苏朔龙军中石化石油化工科学研究院有限公司北京100083

介绍了聚α-烯烃(PAO)合成基础油的分子结构组成与性能之间的关系,其中包括分子结构与黏度、黏度指数和低温流动性之间的关系。通过分析现有的PAO分子结构参数与其黏度、黏度指数和低温流动性之间的关系,梳理出影响黏度的主要分子结构... 详细信息

介绍了聚α-烯烃(PAO)合成基础油的分子结构组成与性能之间的关系,其中包括分子结构与黏度、黏度指数和低温流动性之间的关系。通过分析现有的PAO分子结构参数与其黏度、黏度指数和低温流动性之间的关系,梳理出影响黏度的主要分子结构参数是相对分子质量、支链数量、支链长度和分子的有效长度。分子结构中支链数量、支链长度和支链位置对黏度指数有着重要的影响;支链数量和支链长度对低温流动性能有着重要的影响;支链数量少且较长的PAO分子结构(类似于星型)是兼具好的黏温性能和低温流动性较为理想的结构。因此,从分子水平研究PAO分子结构与性能关系,提炼设计和制备高性能PAO基础油理想结构组分的新思路,为PAO基础油产品升级和新技术的开发提供理论支撑和科学指导。

关键词：聚α-烯烃合成基础油构效关系结构参数低温流动性分子水平

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鱼类肌肉生长研究进展

水产学报 2024年第9期48卷 3-23页

作者：何玉慧李响石军华南农业大学海洋学院岭南现代农业科学与技术广东省实验室

鱼类是人类获取动物蛋白的重要来源，其主要可食用部分为肌肉组织。鱼类水产养殖的本质即通过适宜的养殖条件和技术，促使鱼类肌纤维快速增殖和迅速肥大，达到肌肉快速生长、提高养殖生产效益目的。鱼类肌肉生长的实质为肌纤维增殖和肌... 详细信息

鱼类是人类获取动物蛋白的重要来源，其主要可食用部分为肌肉组织。鱼类水产养殖的本质即通过适宜的养殖条件和技术，促使鱼类肌纤维快速增殖和迅速肥大，达到肌肉快速生长、提高养殖生产效益目的。鱼类肌肉生长的实质为肌纤维增殖和肌纤维增粗，即肌细胞不断融合形成更粗更大肌管的过程；肌管进一步分化、组装并表达一类肌肉特异性蛋白，最终形成两种不同类型的肌纤维：白色肌肉(快肌)和红色肌肉(慢肌)组织。本文系统总结了鱼类肌肉生长最新研究进展，包括鱼类肌纤维结构及形成过程，肌细胞增殖、迁移、分化及肌细胞生长的关键调控因子和信号通路；此外，重点解析了肌细胞融合的关键基因(mymk和mymx)及融合决定因素。另外，本文概述了肌肉生长基因资源在水产育种中的应用，阐述了利用营养条件改良鱼类肉质的可行性，并提出可结合遗传学和营养学手段，合理调节鱼类肌纤维增殖和增粗两种生长模式，实现肌肉快速增长和肉质改良。本综述可为鱼类速生优质品系培育提供理论基础和实践指导。

关键词：鱼类肌肉生长肌纤维增殖肌纤维增粗生肌调节因子肌细胞融合 mymk mymx mstn

Influence of notch volume on mechanical properties of a novel high-strength and high-toughness steel

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Journal of Iron and Steel Research International 2023年第12期30卷 2482-2493页

作者： zhi-gang Tao Ke Qin Shu-lin Ren Hao-tian Xu Man-chao he State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and Technology(Beijing)Beijing100083China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing100083China

The effect of notch volume on the mechanical behavior of a novel high-strength and high-toughness steel with negative Poisson’s ratio effect(called NPR steel)was ***,the quasi-static tensile test of NPR steel with different notch volumes was carried out,and its failure characteristics and mechanical properties parameters were ***,the modified Johnson-Cook(J-C)constitutive model with coupled notch volume ratio was *** model was validated based on three-dimensional finite element numerical *** results show that the engineering stress–strain curve of NPR steel has no yield platform,and has the mechanical properties of high strength,high elongation,and high energy *** volume significantly affects the mechanical properties of NPR *** elongation,yield strength,tensile strength,and energy absorption characteristics of steel bar gradually decrease with the increase in notch *** notch volume ratio V^{*},a characteristic parameter describing the notch volume of reinforcement,is defined,and the quantitative relationship between this parameter and mechanical parameters is established,which can accurately characterize the mechanical properties of specimens with different notch volume *** on the true stress–strain curves with different notch volume ratios,a constitutive model with modified Johnson-Cook model parameters is *** finite element results show that the modified J-C model can accurately fit the quasi-static tensile mechanical behavior of NPR steel.

关键词： High-strength and high-toughness steel Negative Poisson's ratio effect Tensile experiment Notch volume ratio Johnson-Cook constitutive model

Hierarchical Ni-Co-S@Ni-W-O core-shell nanosheet arrays on nickel foam for high-performance asymmetric supercapacitors

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Nano Research 2018年第3期11卷 1415-1425页

作者： Weidong he zhifu liang Keyu ji Qingfeng Sun Tianyou Zhai Xijin Xu School of Physics and Technology University of Jinan 336 West Road of Nan Xinzhuang Jinan 250022 China State Key Laboratory of Material Processing and Die & Mould Technology School of Materials Science and Engineering Huazhong University of Science and Technology (HUST) Wuhan 430074 China School of Engineering Zhejiang A & F University Hangzhou 311300 China

Nickel cobalt sulfides （Ni-Co-S） have attracted extensive attention for application in electronic devices owing to their excellent conductivity and high electrochemical capacitance. To facilitate the large-scale practical application of Ni-Co-S, the excellent rate capability and cyclic stability of these compounds must be fully exploited. Thus, hierarchical Ni-Co-S@Ni-W-O （Ni-Co-S-W） core/shell hybrid nanosheet arrays on nickel foam were designed and synthesized herein via a facile three-step hydrothermal method, followed by annealing in a tubular furnace under argon atmosphere. The hybrid structure was directly assembled as a free-standing electrode, which exhibited a high specific capacitance of 1,988 F·g^-1 at 2 A·g^-1 and retained an excellent capacitance of approximately 1,500 F·g^-1 at 30 A·g^-1, which is superior to the performance of the pristine Ni-Co-S nanosheet electrode. The assembled asymmetric supercapacitors achieved high specific capacitance （155 F·g^-1 at 1 A·g^-1）, electrochemical stability, and a high energy density of 55.1 W·h·kg^-1 at a power density of 799.8 W·kg^-1 with the optimized Ni-Co-S-W core/shell nanosheets as the positive electrode, activated carbon as the negative electrode, and 6 M KOH as the electrolyte.

关键词： core/shell structure free-standing electrode supercapacitors high energy density excellent stability

Selective harvesting at rational intervals promotes carbon sequestration in temperate coniferous and broad-leaved mixed forests in China

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Journal of Forestry Research 2021年第3期32卷 1025-1033页

作者： Jihua Hou Junxia Tian Li Xu Zihao Zhang zhi Chen Nianpeng he Beijing Key Laboratory of Forest Resources and Ecosystem Processes Beijing Forestry UniversityBeijing 100083People’s Republic of China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101People’s Republic of China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049People’s Republic of China Key Laboratory of Vegetation Ecology Ministry of EducationNortheast Normal UniversityChangchun 130024People’s Republic of China

Evidence-based selective cutting at prescribed intervals as part of good forest management can enhance the carbon sequestration capacity of the *** effect of forest management on carbon sequestration has,however,not been ***,carbon content of various organs was measured for 323 tree species,247 shrub species,and233 herb species in seven temperate coniferous and broadleaved mixed forests that were subjected to selective cutting with restoration durations of 100,55,45,36,25,14,and6 years to explore dynamic changes in carbon *** results showed that biomass carbon allocation in different organs followed a pattern:trunk>root>branch>leaf for all *** longer restoration durations,more carbon accumulated in different organs and in ***,when the restoration duration exceeded 50 years,carbon storage in ecosystem was larger than that in primary forests with 100-year cutting intervals,suggesting that a reasonable selective cutting interval can increase forest carbon *** diameter at breast height(DBH)and forest carbon storage were significantly positively correlated,and carbon storage of selectively cut forests exceeded that of primary forests when the stand mean DBH exceeded 15.66 ***,mean DBH of forests can be an indicator for combining sustainable forest management and forest carbon ***,the classic coefficients of 0.45 and 0.50 used to estimate carbon sequestration underestimated values by 2.65%and overestimated by 8.16%,respectively,in comparison with the measured carbon content from different plant organs.

关键词： Selective cutting Forests Diameter at breast height Carbon Storage Management Restoration

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基于多尺度特征融合的光伏组件缺陷检测

计算机工程与应用 2024年第3期60卷 340-347页

作者：田浩周强贺晨龙陕西科技大学电气与控制工程学院西安710000

针对光伏组件缺陷背景复杂,缺陷尺度差异较大,小目标缺陷较多等传统目标检测算法无法解决的问题,提出了一种基于多尺度特征融合的光伏组件缺陷检测算法。算法以YOLOv5s为框架,在主干网络中嵌入坐标注意力机制,用于提取重要的缺陷形态,... 详细信息

针对光伏组件缺陷背景复杂,缺陷尺度差异较大,小目标缺陷较多等传统目标检测算法无法解决的问题,提出了一种基于多尺度特征融合的光伏组件缺陷检测算法。算法以YOLOv5s为框架,在主干网络中嵌入坐标注意力机制,用于提取重要的缺陷形态,增强网络特征提取能力;在颈部网络中使用双向特征金字塔,以自适应权重的方式融合不同尺度的图像特征;在预测层添加微小目标检测层,并结合ASFF检测头自适应融合不同输出层,减少目标特征信息丢失。在光伏组件数据集上进行验证,实验表明改进后的算法可以快速精准识别缺陷,其中mAP达到了91.9%,召回率达到了90.8%,相比于YOLOv5s网络,mAP和召回率分别提升了3.2、4.5个百分点。

关键词：光伏组件 YOLOv5 缺陷检测特征融合