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International Journal of Mental Health Promotion 2024年第3期26卷 221-228页

作者： Feng Sheng chen kong Chao Li Teaching Department of Sports Qufu Normal UniversityQufu273165China Teaching Department of Sports Shandong Management UniversityJinan250100China General Education Center Weifang Vocational CollegeWeifang262737China

Objective:This study was conducted to explore the relationships among sedentary behavior(SB),electronic product addiction(EPA),and depression(D)in adolescents during the COVID-19 ***:A total of 604 adolescents(including 309 girls and 295 boys aged 12-18)were selected from Qufu City,Shandong Province,China for three rounds of *** model was constructed using AMOS 23.0 software,and cross-lagged analysis was ***:SB at T1 can significantly positively predict SB and EPA at T2(p<0.05).EPA at T1 can significantly positively predict SB and D at T2(p<0.05).Physical activity level and SB at T2 can significantly predict SB and EPA at T3(p<0.05).EPA at T2 can significantly predict SB,EPA,and D at T3(p<0.05).Conclusions:SB and EPA are predictive factors for ***,SB can significantly positively predict D and indirectly predict D through the mediating effect of EPA.

关键词： COVID-19 electronic product addiction depression sedentary behavior

Enhanced cyclic stability of partially disordered spinel cathodes through direct fluorination with gaseous fluorine

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Rare Metals 2024年第4期43卷 1635-1646页

作者： Yong-Nian Ma Ling-chen kong Shao-Shan chen Yong Wang Li-Dong Sun Cong Peng Meng-Meng Qin Yu Li Wei Feng Tianjin Key Laboratory of Composite and Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjin300072China Institute of Advanced Technology and Equipment Beijing University of Chemical TechnologyBeijing100029China

Spinel-type cathodes are considered an optimal substitute for conventional layered oxide cathodes owing to their use of inexpensive and earth-abundant manganese as the redox-active ***,the introduction of cation disorder can effectively suppress the detrimental two-phase reaction to realize high capacities in a wide voltage ***,the continuous capacity decay during cycles has hindered the widespread application of these cathode *** fluorides exhibit excellent electrochemical stability at high voltage;therefore,in this study,the direct F2 gas reaction with a partially disordered spinel cathode(Li_(1.6)Mn_(1.6)O_(3.7)F_(0.3,)LMOF1.6)was initially applied to investigate the impacts of fluorination on the surface structure and electrochemical *** inorganic fluorinated layer,mainly containing LiF,was distributed uniformly on the surface of LMOF1.6nanoparticles after fluorination for an appropriate time without the turbulence caused by the valency of manganese cation,which improved the capacity retention and rate capability by the suppression of structural damage,parasitic reaction,and cation *** LMOF1.6cathode fluorinated for 0.5 h exhibited a capacity of283.6 mAh·g^(-1)at 50 mA·g^(-1)and an enhanced capacity retention of 29.6%after 50 cycles in the voltage range of1.5-4.8 V,as compared to the pristine LMOF1.6 with only27.9%capacity retention.

关键词： Spinel-type cathodes Direct fluorination Capacity retention ability High rate capability

改进Reddy型三阶剪切变形理论下FG-GRC板弯曲和模态分析的无网格法

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振动与冲击 2024年第2期43卷 79-87,305页

作者：杨立军陈孔陈卫湖南文理学院芙蓉学院湖南常德415000 中国建筑第八工程局有限公司南方公司南宁530004 南华大学土木工程学院湖南衡阳421001

基于含7个自由度变量的改进Reddy型三阶剪切变形理论(third-order deformation theory,TSDT)假设,采用稳定移动最小二乘近似(stabilized moving least-square approximation,SMLS)的无网格法研究了功能梯度石墨烯增强复合材料(functionally graded graphene-reinforced composite,FG-GRC)板结构的静态线性弯曲和自振模态。通过Halpin-Tsai模型来估算材料的有效弹性模量,有效质量密度和泊松比由混合定律确定。利用最小势能原理和Hamition原理分别推导了FG-GRC板的线性弯曲和自振频率无网格控制方程。由于基于SMLS构造的形函数不满足克罗内克条件,故采用完全转换法处理本质边界条件。该研究首先介绍了基于TSDT下FG-GRC板的SMLS离散模型;随后通过与已有成果进行比较,检验了本文方法的收敛性及准确性;最后数值分析了石墨烯片(graphene platelets,GPLs)分布模式,质量分数、几何参数、总层数及边界条件等对FG-GRC板结构弯曲和模态的影响。

关键词：改进Reddy型三阶剪切变形理论(TSDT) 功能梯度石墨烯增强复合材料板稳定移动最小二乘近似(SMLS) 线性弯曲自振频率

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农村土地流转研究综述

粮食科技与经济 2024年第3期49卷 50-55页

作者：孔晨河南财经政法大学农业农村发展学院河南郑州450046

自20世纪90年代以来,中国城市化进程速度加快,大量农民工进城务工,加快了土地流转。党的十九大报告提出乡村振兴战略政策,以促进土地资源的有效利用。文章通过梳理中国知网2020—2023年与土地流转相关的文献,发现诸多学者研究土地流转,... 详细信息

自20世纪90年代以来,中国城市化进程速度加快,大量农民工进城务工,加快了土地流转。党的十九大报告提出乡村振兴战略政策,以促进土地资源的有效利用。文章通过梳理中国知网2020—2023年与土地流转相关的文献,发现诸多学者研究土地流转,内容涉及土地流转发展现状、土地流转收入、土地流转意愿影响因素、土地流转租金、土地流转在发展过程中面临的困境和问题。基于此,对土地流转的现有研究进行述评,为后期研究提供思路和方向。

关键词：农村土地流转文献综述

应用胶体金免疫层析法检测饲料中恩拉霉素残留的方法建立

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生物工程学报 2024年第7期40卷 2346-2356页

作者：王康余璞陈孔陈敏蔡永辉王冰清浙江工商大学食品与生物工程学院浙江杭州310018

为了实现饲料中恩拉霉素的快速检测,本研究开发了基于抗恩拉霉素A单克隆抗体(anti-enramycin A monoclonal antibody,anti-Er.A-m Ab)的竞争抑制胶体金免疫层析试纸条。以实验室制备的高纯度抗恩拉霉素A单克隆抗体制备胶体金探针,并考... 详细信息

为了实现饲料中恩拉霉素的快速检测,本研究开发了基于抗恩拉霉素A单克隆抗体(anti-enramycin A monoclonal antibody,anti-Er.A-m Ab)的竞争抑制胶体金免疫层析试纸条。以实验室制备的高纯度抗恩拉霉素A单克隆抗体制备胶体金探针,并考察了标记p H、抗体标记量、检测线浓度对恩拉霉素胶体金免疫层析试纸条的影响。在碳酸钾添加量为8μL、抗体标记量为4μg/m L、检测线划膜浓度为1.0 mg/m L、金标抗体使用量为3μL的条件下制备得到的胶体金试纸条特异性好、检出限低。经胶体金读数仪测定,恩拉霉素A检出限为25 ng/m L、线性范围为25-300 ng/m L。选用畜禽饲料进行阳性样本添加实验,结果显示检测结果重复性好,比高效液相色谱法更为灵敏,适合大批量饲料样本的恩拉霉素快速检测。

关键词：恩拉霉素胶体金技术单克隆抗体竞争抑制法

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论裁判设立居住权的司法路径

人民司法 2024年第1期 4-9页

作者：顾全孔晨张文谨上海市嘉定区人民法院

由于立法的微言大义,对于裁判是否可以创设居住权,无论在实务中还是在理论上都存在争议。如果答案是否定的,那么须要进一步回答的问题则是,如何满足司法实践的客观需要;如果答案是肯定的,那么在哪些情形中、应当以何种标准来创设居住权... 详细信息

由于立法的微言大义,对于裁判是否可以创设居住权,无论在实务中还是在理论上都存在争议。如果答案是否定的,那么须要进一步回答的问题则是,如何满足司法实践的客观需要;如果答案是肯定的,那么在哪些情形中、应当以何种标准来创设居住权,则是值得被细致研究的问题。本期策划展示了实务工作者与理论研究者对上述问题的思考。

关键词：居住权实务工作者司法路径微言大义司法实践裁判创设

基于三电平的超声波电机驱动电路调速性能研究

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微特电机 2024年第1期52卷 51-57页

作者：傅平孔晨蔡康伟闽江学院物理学与电子信息工程学院福州350121 闽江学院福建省教育厅先进运动控制重点实验室福州350121 温州大学电气与电子工程学院温州325000

从超声波电机驱动电路拓扑结构出发,使用三相全桥电路构建三电平波形发生电路,得到基于三电平的超声波电机驱动电路,通过改变相关PWM驱动参数可以实现电机驱动波形的调频、调压和调相功能,进而实现电机调速。通过分析得到驱动电压、驱... 详细信息

从超声波电机驱动电路拓扑结构出发,使用三相全桥电路构建三电平波形发生电路,得到基于三电平的超声波电机驱动电路,通过改变相关PWM驱动参数可以实现电机驱动波形的调频、调压和调相功能,进而实现电机调速。通过分析得到驱动电压、驱动频率与行波幅值之间的关系,使用半实物仿真平台对基于三电平的超声波电机驱动电路进行测试,验证空载、带载时超声波电机在调压、调频、调相的情况下转速的变化情况,从而实现基于三电平的超声波电机的调速性能测试,为电机调速打下基础。

关键词：超声波电机驱动电路三电平半实物仿真

Recent progress of machine learning in flow modeling and active flow control

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Chinese Journal of Aeronautics 2022年第4期35卷 14-44页

作者： Yunfei Li Juntao Chang chen kong Wen Bao School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China

In terms of multiple temporal and spatial scales, massive data from experiments, flow field measurements, and high-fidelity numerical simulations have greatly promoted the rapid development of fluid mechanics. Machine Learning(ML) provides a wealth of analysis methods to extract potential information from a large amount of data for in-depth understanding of the underlying flow mechanism or for further applications. Furthermore, machine learning algorithms can enhance flow information and automatically perform tasks that involve active flow control and optimization. This article provides an overview of the past history, current development, and promising prospects of machine learning in the field of fluid mechanics. In addition, to facilitate understanding, this article outlines the basic principles of machine learning methods and their applications in engineering practice, turbulence models, flow field representation problems, and active flow control. In short, machine learning provides a powerful and more intelligent data processing architecture, and may greatly enrich the existing research methods and industrial applications of fluid mechanics.

关键词： Data-driven modeling Flow control Flow field kinematics Machine learning Neural networks-applications

A deep learning approach for velocity field prediction in a scramjet isolator from Schlieren images

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Chinese Journal of Aeronautics 2023年第11期36卷 58-70页

作者： chen kong Ziao WANG Yunfei LI Juntao CHANG School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China

Accurate measurements of physical parameters in a scramjet isolator are very important to promote the design and optimization of the isolator and even the *** a ground experiment,limited by the inherent characteristics of measurement technology and equipment,it is a big challenge to obtain the velocity field inside an *** this study,a deep learning approach was introduced to combine data obtained from ground experiments and numerical simulations,and a velocity field prediction model was developed for obtaining the velocity field inside an isolator based on experimental Schlieren *** velocity field prediction model was designed with convolutional neural networks as the main *** experiments of a scramjet isolator under continuous Mach number variation were carried out,and Schlieren images of the flow field inside the isolator were *** simulations of the isolator were also carried out,and the velocity fields inside the isolator under various Mach numbers were *** velocity field prediction model was trained using flow field datasets containing experimental Schlieren images and velocity field,and the mapping relationship between the experimental Schlieren images and the predicted velocity field was successfully established.

关键词： Data-driven model Deep learning Neural networks Scramjet isolator Velocity field prediction

农林废弃物共热解对污泥生物炭Cu(Ⅱ)吸附性能的影响

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应用化工 2024年第4期53卷 774-780页

作者：陈晴空王欢范剑平李佳瑛陈炜李彦林杨瑞丰王殿常重庆交通大学河海学院环境水利工程重庆市工程实验室重庆400074 重庆文理学院化学与环境工程学院重庆市环境材料与修复技术重点实验室重庆402160 北京建工环境修复股份有限公司北京100015 重庆交通大学重庆港力环保股份有限公司资源与环境研究生联合培养基地重庆400074 中国长江三峡集团有限公司长江生态环境工程研究中心湖北武汉430014 长江生态环保集团有限公司湖北武汉430062

将山地城市污泥与水稻杆、水稻壳、桉树枝、桉树叶等农林废弃物进行共热解,研究共热解对生物炭理化性质及Cu(II)吸附性能的影响,探讨共热解对Cu(II)吸附性能的协同作用。结果显示,与污泥炭相比,水稻壳、水稻杆、桉树枝、桉树叶与污泥共... 详细信息

将山地城市污泥与水稻杆、水稻壳、桉树枝、桉树叶等农林废弃物进行共热解,研究共热解对生物炭理化性质及Cu(II)吸附性能的影响,探讨共热解对Cu(II)吸附性能的协同作用。结果显示,与污泥炭相比,水稻壳、水稻杆、桉树枝、桉树叶与污泥共热解制备的生物炭,C含量分别增大了0.64倍、0.87倍、1.04倍、1.22倍,O含量分别增大了1.11倍、1.25倍、2.01倍、2.17倍,对Cu(II)最大吸附量分别增大了28.4%,60.3%,82.7%,99.7%。共热解对生物炭Cu(II)吸附性能具有明显的协同作用,污泥与桉树叶共热解炭对Cu(II)最大吸附量的协同量化值最高(90.13%)。

关键词：污泥处理处置生物炭共热解协同效应重金属吸附