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mLife 2024年第1期3卷 143-155页

作者： Jing Zhang Qi-Yun Liang Da-Shuai Mu Fengbai Lian ya gong Mengqi Ye Guan-Jun Chen Yuqi Ye Zong-Jun Du State Key Laboratory of Microbial Techlogy Insttute of Micrbial TchnoogyShandong UniversityQingdaoChina Marine College Shandong UniverstyWeihaiChina Shandong University-Weihai Research Institute of Industrial Technology WeihaiChina

In the classical microbial isolation technique,the isolation process inevitably destroys all microbial interactions and thus makes it difficult to culture the many microorganisms that rely on these interactions for *** this study,we designed a simple coculture technique named the“sandwich agar plate method,”which maintains microbial interactions throughout the isolation and pure culture *** total yield of uncultured species in sandwich agar plates based on eight helper strains was almost 10-fold that of the control *** uncultured species displayed commensal *** study found that heme was the growth-promoting factor of some marine commensal *** genomic analysis revealed that heme auxotrophies were common in various biotopes and prevalent in many uncultured microbial ***,our study supported that the survival strategies of heme auxotrophy in different habitats varied *** findings highlight that cocultivation based on the“sandwich agar plate method”could be developed and used to isolate more uncultured bacteria.

关键词： cultivation growth factors heme sandwich agar plate uncultured bacteria

金融结构、产业结构升级与收入分配--基于新结构经济学的解释

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数理统计与管理 2024年第4期43卷 737-760页

作者：玉国华宫雅慧西南大学经济管理学院重庆400715

本文基于新结构经济学阐释金融结构、产业结构升级影响收入分配的作用机理,利用20002020年中国31个省份的面板数据对三者关系进行实证检验。研究表明:(1)金融结构能否有助于实现收入分配最优化,关键在于金融结构是否与该经济体所处的经... 详细信息

本文基于新结构经济学阐释金融结构、产业结构升级影响收入分配的作用机理,利用20002020年中国31个省份的面板数据对三者关系进行实证检验。研究表明:(1)金融结构能否有助于实现收入分配最优化,关键在于金融结构是否与该经济体所处的经济发展阶段相匹配,且金融制度是否根据产业发展的融资需求形成有效安排,当金融结构与产业结构相契合时,才能最大程度地促进收入均等化。(2)单纯考虑金融结构对产业结构升级的直接影响,金融结构有利于促进产业结构高级化和产业结构合理化,金融结构每提高1个标准单位,产业结构高级化、产业结构合理化将分别提升0.09%、0.58%。(3)进一步探析“金融结构一产业结构升级”影响收入分配的交互效应时,金融结构能够通过产业结构高级化和产业结构合理化抑制收入不平等。(4)采用面板门槛模型估计产业结构升级过程中金融结构缓解收入不平等的最优边际效应区间,结果显示,伴随产业结构由“低级”向“高级”跃迁,当金融结构由“银行主导型”向“市场主导型”转变将有利于缩小社会贫富差距。最后讨论产业结构升级过程中金融结构嵌入式演进以及金融结构与产业结构耦合式发展对实现共同富裕的重要政策涵义。

关键词：金融发展产业升级收入差距共同富裕门槛效应

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TC4钛合金材料铣削加工分析及参数优化

吉林大学学报（工学版） 2024年第4期54卷 917-925页

作者：巩亚东丁明祥李响田近民东北大学机械工程与自动化学院沈阳110819

为探究加工TC4钛合金材料时铣削加工参数对铣削力及材料去除率的影响规律并寻求最佳参数组合,基于正交实验方法设计实验,采用四刃球头铣刀进行侧铣实验。以铣削速度、每齿进给量、铣削深度和铣削宽度为变量,以铣削力和材料去除率为评价... 详细信息

为探究加工TC4钛合金材料时铣削加工参数对铣削力及材料去除率的影响规律并寻求最佳参数组合,基于正交实验方法设计实验,采用四刃球头铣刀进行侧铣实验。以铣削速度、每齿进给量、铣削深度和铣削宽度为变量,以铣削力和材料去除率为评价指标,基于极差分析法,揭示加工参数对铣削力和材料去除率的影响规律。分别采用灰色关联分析法(GRA)和粒子群优化(PSO)算法进行参数优化,基于回归分析方法建立铣削力预测模型,为PSO做准备。最后,经过试验验证,对两种优化方法进行对比分析,并对预测模型进行验证。结果表明,本文所建立的预测模型可准确高效地对铣削力进行预测,PSO优化效果更好。

关键词：机械制造钛合金铣削力材料去除率灰色关联分析粒子群优化

基于弹射救生安全影响因素的弹射过程视景仿真分析

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长沙航空职业技术学院学报 2024年第1期24卷 13-15,33页

作者：巩亚龙戴迪中国飞行试验研究院陕西西安710089

弹射救生技术是在飞机不可挽回状态下拯救飞行员生命的重要技术。通过分析装备方面、人为方面、环境和状态方面的弹射救生安全影响因素,梳理弹射救生的整个过程,提出了视景仿真系统的总体设计,并构建了弹射救生系统发射过程中的弹射出... 详细信息

弹射救生技术是在飞机不可挽回状态下拯救飞行员生命的重要技术。通过分析装备方面、人为方面、环境和状态方面的弹射救生安全影响因素,梳理弹射救生的整个过程,提出了视景仿真系统的总体设计,并构建了弹射救生系统发射过程中的弹射出舱阶段、人-椅系统自由飞阶段和救生伞工作阶段的数学模型,对数值仿真得出的数据结果进行了分析,得到了影响仿真中弹射救生关键点的几个因素,运用3DMAX软件和Unity3D软件实现弹射过程的模拟仿真,以便直观形象地展示弹射救生过程。

关键词：弹射救生安全影响因素弹射救生过程数学模型视景仿真

单环调节轴对称收扩喷管全包线推力特性数值分析

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航空发动机 2024年第4期50卷 82-87页

作者：张瑞霞许羚巩亚南夏子龙中国航发沈阳发动机研究所沈阳110015

为了研究单环调节轴对称收扩喷管的全包线推力系数变化规律,采用经模型试验验证的数值仿真方法,对该类型喷管推力系数的影响因素、面积比设计方法和全包线推力特性开展数值分析。结果表明:在非加力状态下,喷管常用落压比为3~4,处于低落... 详细信息

为了研究单环调节轴对称收扩喷管的全包线推力系数变化规律,采用经模型试验验证的数值仿真方法,对该类型喷管推力系数的影响因素、面积比设计方法和全包线推力特性开展数值分析。结果表明:在非加力状态下,喷管常用落压比为3~4,处于低落压比状态,喷管推力系数在面积比为1.1~1.2时较优;在加力状态下,喷管常用落压比为4~8,推力系数在面积比为1.3~1.5时较优。基于包线内结构可达目标,开展推力特性全局优化,优化后在非加力状态下,喷管推力系数为0.959~0.992;在加力状态下,喷管推力系数为0.956~0.993;随着飞行高度的增加,包线内喷管实际使用落压比区间逐渐右移,推力系数先增大后减小。编制了单环调节轴对称收扩喷管推力特性的快速分析程序,可实现全包线推力性能点群的高效预估。

关键词：单环调节收扩喷管推力特性落压比面积比快速分析程序

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Recent advances in electrocatalysts for non-aqueous Li-O2 batteries

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Chinese Chemical Letters 2017年第4期28卷 709-718页

作者： Wei Chen ya-Feng gong Jie-Hua Liu Future Energy Laboratory School of Materials Science and Engineering Hefei University of Technology Hefei 230009 China

As one of the next-generation energy-storage devices,Li-O_2 battery has become the main research direction for the academic researchers due to its characteristics of environmental friendship,relatively simple structures,high energy density of 3500Wh/kg and low ***,Li-O_2 battery cannot be commercialized on a large scale because of the challenging issues including high-efficient electrocatalysts,membranes,Li-based anode and so *** this review,we focused on the recent development of electrocatalyst materials as cathodes for the non-aqueous Li-O_2 batteries which are relatively simpler than other Li-O_2 batteries＇ *** were summarized including noble metals,nanocarbon materials,transition metals and their *** points out that the challenges of preparation high-efficient catalysts not only require high catalytic activity and conductivity,but also have novel nanoarchitectures with large interface and porous volume for LiO_x ***,the further investigation of reaction mechanism and advanced in situ analysis technologies are welcome in the coming work.

关键词： Electric vehicle Li-O2 battery High capacity Catalysts Electrocatalysis

Research on the nanometric machining of a single crystal nickel via molecular dynamics simulation

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Science China(Technological Sciences) 2016年第12期59卷 1837-1846页

作者： gong ya Dong ZHU Zong Xiao ZHOU Yun Guang SUN yao School of Mechanical Engineering & Automation Northeastern University

Molecular dynamics simulations are employed to study the nanometric machining process of single crystal nickel. Atoms from different machining zones had different atomic crystal structures owing to the differences in the actions of the cutting tool. The stacking fault tetrahedral was formed by a series of dislocation reactions, and it maintained the stable structure after the dislocation reactions. In addition, evidence of crystal transition and recovery was found by analyzing the number variations in different types of atoms in the primary shear zone, amorphous region, and crystalline region. The effects of machining speed on the cutting force, chip and subsurface defects, and temperature of the contact zone between the tool and workpiece were investigated. The results suggest that higher the machining speed, larger is the cutting force. The degree of amorphousness of chip atoms and the depth and extent of subsurface defects increase with the machining speed. The average friction coefficient first decreases and then increases with the machining speed because of the temperature difference between the chip and machining surface.

关键词： molecular dynamics simulation nanometric machining single crystal nickel crystal transition and recovery machining speed

Progress in application and preparation of silver nanowires

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Rare Metals 2016年第4期35卷 289-298页

作者： Xiong-Zhi Xiang Wen-ya gong Ming-Sheng Kuang Lei Wang Shenzhen Key Laboratory of Polymer Science and Technology College of Materials Science and EngineeringShenzhen University

Silver nanowires have attracted wide research attention for their excellent optical, electrical and chemical properties. Many researches were performed toward syn- thesizing and application of silver nanowires. The appli- cation of silver nanowires such as transparent conductive film electrode, conductive silver adhesive and nanowelding technology was introduced herein. Principles and charac- teristics of different synthesizing methods of silver nano- wires were reviewed in this paper, including template method, liquid polyol method, self-assembly method, ultrasonic reduction method and wet chemical method. The liquid polyol method was the most available one to achieve efficient large-scale production.

关键词： Silver nanowires Applications Synthesizingtechnologies

Impact of ventilation design on the precooling effectiveness of horticultural produce-a review

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Food Quality and Safety 2020年第1期4卷 29-40页

作者： Yuhui Cao ya-Fang gong Xin-Rong Zhang College of Engineering Sciences University of Chinese Academy of SciencesBeijingChina Department of Energy and Resource Engineering College of EngineeringPeking UniversityBeijingChina

Optimizing the ventilation design of packaging system is of crucial importance for improving the efficiency of the forced-air precooling process to maintain the quality of horticultural produce and extend the shelf life in food cold *** efforts had been devoted to the study about the impact of ventilation design on airflow and temperature distribution inside ventilated *** paper reviews relevant research methods,commonly used quantities for the measurement of precooling effectiveness,attractive design parameters,and their impact on precooling *** allow us to know exactly the characteristic and deficiency of each research method,identify dominant design parameters,and seek a promising way for the future improvement of the ventilated packaging system.

关键词： horticultural produce precooling effectiveness ventilation design forced-air precooling technique packaging system

Some Special Properties of Singular Integral Operators

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Wuhan University Journal of Natural Sciences 1999年第3期4卷 269-274页

作者： gong ya-fang Du Jin-yuan Wuhan Univ China

In this paper, we have proved some special properties of singular integral operators which are transformed from the singular integral equation defined in the interval (?1, 1), i.e., the properties of singular intergra... 详细信息

关键词： singular integral canonical function generalized Jacobi weight