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Defence Technology（防务技术） 2021年第4期17卷 1572-1578页

作者： zhi Yang Ke Wang Peng Zhu Peng Liu qiu Zhang Cong Xu Hao-tian Jian Rui-qi shen School of Chemical Engineering Nanjing University of Science and TechnologyNanjing210094China Key Laboratory of Special Energy Materials Ministry of EducationNanjing210094China Micro-Nano Energetic Devices Key Laboratory Ministry of Industry and Information TechnologyNanjing210094China

Triggered spark-gap switch is a popular discharge switch for pulse power *** studies have focused on planarizing this switch using thin film techniques in order to meet the requirements of compact size in the *** switches are one-shot due to electrodes being too thin to sufficiently resist ***,these switches did not employ any structures in securing internal gas composition,resulting in inconsistent performance under harsh *** this work,a novel planar triggered spark-gap switch(PTS)with a hermetically sealed cavity was batched-prepared with printed circuit board(PCB)technology,to achieve reusability with low *** proposed PTS was inspected by micro-computed tomography to ensure PCB techniques meet the requirements of machining *** results from electrical experiments demonstrated that PCB PTS were consistent and reusable with lifespan over 20 *** calculated switch voltage and circuit current were consistent with those derived from real-world ***,PCB PTS was used to introduce hexanitrostilbene(HNS)pellets in a pulse power system to verify its performance.

关键词： Pulse power systems Printed circuit board technology Triggered spark-gap switch Planar discharge switch Electrical performance

Study of primordial deuterium abundance in Big Bang nucleosynthesis

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Nuclear Science and Techniques 2024年第3期35卷 208-215页

作者： zhi-Lin shen Jian-Jun He Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China

Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)He,^(4)He,and^(7) Li produced in the early *** these,deuterium,the first nuclide produced by BBN,is a key primordial material for subsequent *** date,the uncertainty in predicted deuterium abundance(D/H)remains larger than the observational *** this study,the Monte Carlo simulation code PRIMAT was used to investigate the sensitivity of 11 important BBN reactions to deuterium *** found that the reaction rate uncertainties of the four reactions d(d,n)^(3)He,d(d,p)t,d(p,γ)^(3)He,and p(n,γ)d had the largest influence on the calculated D/H ***,the calculated D/H uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) He *** the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved in BBN are still necessary.A photodisintegration experiment will be conducted at the Shanghai Laser Electron Gamma Source Facility to precisely study the deuterium production reaction of p(n,γ)d.

关键词： Big Bang nucleosynthesis Abundance of deuterium Reaction cross section Reaction rate Monte Carlo method

Oscillation of Numerical Solution in the Runge-Kutta Methods for Equation x'(t)=ax(t)+a_0x([t])

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Acta Mathematicae Applicatae Sinica 2014年第4期30卷 943-950页

作者： Qi WANG shen-shan qiu School of Apllied Mathematics Guangdong University of Technology CSIB Software Technology Center The Administrative Commission of Guangzhou Tianhe Software Park

The paper de ls with oscillation of Runge-Kutta methods for equation x＇（t） = ax（t）＋ aox（[t]）. The conditions of oscillation for the numerical methods are presented by considering the characteristic equation of the corresponding discrete scheme. It is proved that any nodes have the same oscillatory property as the integer nodes. Furthermore, the conditions under which the oscillation of the analytic solution is inherited by the numerical solution are obtained. The relationships between stability and oscillation are considered. Finally, some numerical experiments are given.

关键词： piecewise continuous arguments Runge-Kutta methods stablity oscillation

Recent progress in studies of factors that elicil pancreatic β-cell expansion

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Protein & Cell 2015年第2期6卷 81-87页

作者： qiu Li zhi-Chun Lai Shandong Provincial Hospital Affiliated to Shandong University Jinan 250021 ChinaA Department of Biology The Pennsylvania State University University Park PA 16802 USA Department of Biochemistry and Molecular Biology The Pennsylvania State University University Park PA 16802 USA

The loss of or decreased functional pancreatic β-cell is a major cause of type 1 and type 2 diabetes. Previous studies have shown that adult β-cells can maintain their ability for a low level of turnover through replication and neogenesis. Thus, a strategy to prevent and treat dia- betes would be to enhance the ability of β-cells to increase the mass of functionalβ-cells. Consequently, much effort has been devoted to identify factors that can effectively induce β-cell expansion. This review focuses on recent reports on small molecules and protein fac- tors that have been shown to promote β-cell expansion.

关键词： pancreatic islet β-cell cell proliferation/replication/expansion cell signaling

Bacterial leaching of discarded copper ores from Yongping, China

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Journal of University of Science and Technology Beijing 2005年第4期12卷 294-297页

作者： Muqing qiu Genxuan Wang Zhuxia shen College of Life Sciences Zhejiang University Hangzhou 310029 China

The elementary and phase analysis of discarded copper ores from Yongping of China has been performed. The experi- ments of extracting copper from the discarded copper ores were done with the mixed bacteria obtained through a series of enrichment, separation, domestication and combination tests. The results show that in the process of bioleaching, the pH value rises at first and drops gradually. The Eh value keeps rising along with the time and the appropriate Eh value varying between 750 and 800 mV will benefit the bioleaching copper. The high concentration of ferric ions is detrimental to the bioleaching copper. The results of bioleaching copper are good. That is, the copper recovery is 31.8% after 27 days.

关键词： bioleaching discarded copper ores mixed bacteria

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陶瓷装饰在室内设计中的应用研究

佛山陶瓷 2025年第2期35卷 98-100,121页

作者：沈子高王求合肥职业技术学院安徽合肥238000

随着现代室内设计的不断发展,陶瓷作为一种古老而丰富的装饰材料,其在室内空间的应用日益受到重视。论文首先概述了陶瓷装饰与室内设计的关系,然后探讨了陶瓷艺术在室内设计中的功能和表现。最后,由陶瓷装饰发展现状提出了针对当前设计... 详细信息

随着现代室内设计的不断发展,陶瓷作为一种古老而丰富的装饰材料,其在室内空间的应用日益受到重视。论文首先概述了陶瓷装饰与室内设计的关系,然后探讨了陶瓷艺术在室内设计中的功能和表现。最后,由陶瓷装饰发展现状提出了针对当前设计趋势的陶瓷装饰创新设计策略。研究不仅为设计师提供了陶瓷装饰在室内设计中的参考,也为陶瓷产业的创新发展提供了一定的理论支持,让陶瓷装饰与室内设计碰撞出新的火花。

关键词：陶瓷装饰室内设计表现形式创新应用

PE管在黄土地区桥梁纵向集中排水应用中的若干问题探讨

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公路 2025年第1期70卷 224-228页

作者：贾志刚邱大威林永楷山西离隰高速公路有限公司吕梁市033400 中交第一公路勘察设计研究院有限公司西安市710075

黄土地区公路桥梁建设时,由于环、水、保等方面的要求,越来越多的桥梁采用桥面集中排水设计。聚乙烯(Polyethylene,简称PE)排水管因其出色的耐久性和环保特性,取代了传统PVC管材应用于宁夏黄土地区公路——G85银昆高速太彭段项目中。然... 详细信息

黄土地区公路桥梁建设时,由于环、水、保等方面的要求,越来越多的桥梁采用桥面集中排水设计。聚乙烯(Polyethylene,简称PE)排水管因其出色的耐久性和环保特性,取代了传统PVC管材应用于宁夏黄土地区公路——G85银昆高速太彭段项目中。然而,PE排水管在桥面集中排水系统设计和施工过程中出现了诸多问题,包括固定方式、连接方式及热胀冷缩大变形破坏等,尤其是在西北地区温差变化大、桥梁高度大时,这些问题显得尤为突出。对G85银昆高速太彭段桥梁集中排水PE管在实施过程遇到的问题进行总结,提出了处理措施,为其他黄土地区桥梁集中排水提供参考。

关键词：桥梁工程黄土地区桥梁 PE桥面集中排水管热胀冷缩连接问题处理措施

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Growth kinetics and mechanism of microarc oxidation coating on Ti-6Al-4V alloy in phosphate/silicate electrolyte

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International Journal of Minerals,Metallurgy and Materials 2022年第11期29卷 1991-1999页

作者： Dajun Zhai Tao qiu Jun shen Keqin Feng College of Materials Science and Engineering Chongqing UniversityChongqing 400044China School of Mechanical Engineering Sichuan UniversityChengdu 610065China

Microarc oxidation(MAO)is an effective surface treatment method for Ti alloys to allow their application in extreme ***,binary electrolytes consisting of different amounts of sodium phosphate and sodium silicate were designed for *** surface morphology,composition,and properties of MAO coatings on Ti-6Al-4V alloy treated in 0.10 mol/L electrolyte were investigated to reveal the effect of PO_(4)^(3-)and SiO_(3)^(2-)ray diffraction,and potentiodynamic *** results showed that PO_(4)^(3-)is beneficial for generating microarcs and forming pores within the coating,resulting in a thick but porous ***_(3)^(2-)eration of microarcs,resulting in a thin dense *** thickness,density,phases content,and polarization resistance of the MAO coatings are primarily affected by the intensity of microarcs for low SiO_(3)^(2-)ciently *** thickness of MAO coatings obtained in P/Si electrolytes shows a piecewise linear increase with increasing process time during the three stages of microarc ***_(3)^(2-)discharge,but slows down the growth of the coating formed in the next stage.

关键词： microarc oxidation titanium alloy phosphate silicate growth kinetics growth mechanism

Optimality Conditions of the Set-valued Optimization Problem with Generalized Cone Convex Set-valued Maps Characterized by Contingent Epiderivative

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Acta Mathematicae Applicatae Sinica 2018年第1期34卷 11-18页

作者： zhi-ang ZHOU Xin-min YANG qiu-sheng qiu College of Sciences Chongqing University of Technology Chongqing 400054 China College of Mathematical Sciences Chongqing Normal University Chongqing 400047 China Department of Mathematics Zhejiang Normal University Jinhua 321004 China

In this paper, firstly, a new notion of generalized cone convex set-valued map is introduced in real normed spaces. Secondly, a property of the generalized cone convex set-valued map involving the contingent epiderivative is obtained. Finally, as the applications of this property, we use the contingent epiderivative to establish optimality conditions of the set-valued optimization problem with generalized cone convex set-valued maps in the sense of Henig proper efficiency. The results obtained in this paper generalize and improve some known results in the literature.

关键词： set-valued maps generalized cone convexity Henig proper efficiency contingent epiderivative optimality conditions

规模化畜禽养殖粪便中接合型耐药质粒污染及耐药基因赋存特征

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环境科学 2025年第2期46卷 1245-1254页

作者：李莹申磊高浩泽郭雅杰王旭明赵国柱仇天雷北京林业大学生物科学与技术学院北京100083 北京市农林科学院生物技术研究所北京100097 廊坊师范学院生命科学学院廊坊065000

近年来,细菌病原体中抗生素耐药性的出现和传播对公众健康构成严重的威胁.为了解规模化养殖畜禽粪便中质粒介导的可移动抗生素耐药基因(ARGs)的赋存情况和转移特征,对北京、河北和宁夏等地区的蛋鸡、肉鸡和生猪规模化养殖场粪便进行耐... 详细信息

近年来,细菌病原体中抗生素耐药性的出现和传播对公众健康构成严重的威胁.为了解规模化养殖畜禽粪便中质粒介导的可移动抗生素耐药基因(ARGs)的赋存情况和转移特征,对北京、河北和宁夏等地区的蛋鸡、肉鸡和生猪规模化养殖场粪便进行耐药接合型质粒(CARP)的捕获与分析.采用滤膜接合法对养殖场畜禽粪便中的CARP进行捕获并计算转移频率和流行率.通过接合子基因组二代测序获得质粒携带ARGs信息,比对PlasimidFinder数据库鉴定耐药质粒的复制子类型.利用药敏纸片扩散法(Kirby-Bauer法)对接合子进行耐药表型测定.结果表明,35个规模化养殖场捕获了125个CARP,共携带13类65种ARGs,最常见的ARGs为floR、aac(6')-lb7和TEM-150.不同养殖动物粪便中CARP流行情况有一定差异,其中蛋鸡粪中CARP具有更高的转移能力和流行率,但其多重耐药程度要弱于肉鸡和猪粪.共检出49种共有的ARGs,其中64%属于氨基糖苷类、 β-内酰胺类、氟喹诺酮类和甲氧苄啶类.64株典型接合子的耐药表型也有类似特点,主要对β-内酰胺类(95.31%)、四环素类(89.06%)、氨基糖苷类(87.5%)和氟喹诺酮类(68.75%)抗生素耐药率较高.猪粪中检出IncH型、IncN型和IncR型这3种广宿主范围质粒,猪场中12.5%接合子携带5个及以上高风险ARGs,比例高于其他养殖场.研究表明,畜禽粪便中CARP普遍携带多种类型的ARGs,使宿主菌具有多种抗生素耐药能力;高风险ARGs被广宿主范围接合型质粒所携带,增加了其由养殖场向周边环境传播的风险.

关键词：畜禽养殖接合型质粒抗生素耐药基因(ARGs) 表型复制子