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Development of a 750-mm-long stripline kicker for HEPS

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Radiation Detection Technology and Methods 2018年第2期2卷 121-127页

作者： H.shi J.H.Chen l.Wang N.Wang l.H.Huo G.W.Wang P.liu x.l.shi Key laboratory of Particle Acceleration Physics and Technology Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

Purpose The superfast kickers are required for the HEPS storage ring on-axis injection system due to its very small dynamic aperture.A 750-mm-long stripline pair type of kicker prototype was researched and developed to demonstrate achieved performance of bandwidth,impedance,kicker strength,field uniformity and beam power *** The cross sections of the kicker main body and the end of taper part are optimized for a good impedance matching and field uniformity.3D simulation further optimizes the taper part to minimize the beam power loss and maintain a lower *** high-voltage feedthrough is also designed and optimized by 3D *** and high-voltage measurements are taken to verify the design of kicker *** The testing transmission odd-mode impedance is 50±0.5Ω,the even-mode impedance is 60±0.5Ω,and return loss is less than−13 *** peak voltage and the rise time of pulse width inserting kicker assembly just decrease 3%of 20 kV and slow down 80 ps,*** RF testing results agree well with the simulation ones,which meet the design *** kicker assembly works well at±20 kV pulse.

关键词： Stripline kicker Feedthrough On-axis swap-out injection Odd-mode(even-mode)impedance Storage ring

Enhancing force sensing in a squeezed optomechanical system with quantum nondemolition measurement

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Communications in Theoretical Physics 2024年第1期76卷 49-60页

作者： shi-lei Chao Zi-Hao li xin-You lü School of Physics Huazhong University of Science and Technology430074 WuhanChina

A theoretical scheme is proposed to enhance the sensitivity of force sensors with quantum nondemolition measurement(QND)in an optomechanical setup assisted by four-tone optical driving and an optical parametric amplifier(OPA).With the help of special drive,the system can be simplified as the typical type of QND for force sensing,so that the backaction noise can be evaded to surpass the standard quantum ***,the added noise can be suppressed owing to the modified optical susceptibility resulting from the *** introducing two oscillators coupling with two charged bodies respectively,the signal can be enhanced with the nonlinearity caused by Coulomb interaction,while the noise presents an exponential ***,considering the homodyne detection effect,the range of system parameters and frequency bands will be *** present investigation may provide a route toward simultaneously evading backaction noise,reducing the mechanical thermal noise,and enhancing the external signal,which can be an alternative design for sensitive devices.

关键词： force sensing optical parametric amplifier quantum non-demolition measurement optomechanical system

Research on the PB/MCMB/graphite composite for bipolar plate in PEMFC

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Research on the PB/MCMB/graphite composite for bipolar plate...

Metabolic Engineering of Carotenoid Formation in Carrot Roots

第九届全国氢能学术会议

作者： x.l.shi,M.Y.Hang,H.J.Ni Nantong University,China

＜正＞Bipolar plate is the vital component of proton exchange membrane fuel cell（PEMFC）, which supplies fuel and oxidant to reactive sites,removes reactive products,provides mechanical support for the cells in the stack collects and produces *** order to reduce the costs,to simplify the manufacture process,to improve the performances and to promote

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来源： cnki会议评论

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分子植物育种 2007年第2期5卷 285-286页

作者： R. Qian　 x.D. lu　 C. Bai　 Q.J. Yang 　l.x. shi 　C.F. Zhu School of life Sciences Northeast Normal University Changchun 130024 China College of Gardening Northeast Forestry University Harbin 150040 China

Carotenoids, a large class of yellow, orange and red pigments accumulate in the chloroplasts of leaves or in the chromoplasts of many flowers and fruits as well as carrot roots. In plants, carotenoids function as

关键词：胡萝卜类胡萝卜素新陈代谢植物根部

Effect of Al_(2)O_(3)on the Mechanical Properties of(B_(4)C+Al_(2)O_(3))/Al Neutron Absorbing Materials

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Acta Metallurgica Sinica(English letters) 2024年第8期37卷 1411-1420页

作者： J.x.Cai B.M.shi N.li Y.liu Z.G.Zhang Y.N.Zan Q.Z.Wang B.l.xiao Z.Y.Ma shi‑Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Key laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Nuclear Equipment Division Beijing Institute of Nuclear EngineeringChina Nuclear Power Engineering Co.Ltd.Beijing 100840China Department of Materials Science School of Mechanical EngineeringShenyang UniversityShenyang 110044China

B_(4)C/Al composites are widely utilized as neutron absorbing materials for the storage and transportation of spent nuclear *** order to improve the high-temperature mechanical properties of B_(4)C/Al composites,in-situ nano-Al_(2)O_(3)was introduced utilizing oxide on Al powder *** this study,the Al_(2)O_(3)content was adjusted by utilizing spheroid Al powder with varying diameters,thereby investigating the impact of Al_(2)O_(3)content on the tensile properties of(B_(4)C+Al_(2)O_(3))/Al *** was found that the pinning effect of Al_(2)O_(3)on the grain boundaries could hinder the recovery of dislocations and lead to dislocation accumulation at high *** the result,with the increase in Al_(2)O_(3)content and the decrease in grain size,the high-temperature strength of the composites increased *** finest Al powder used in this investigation had a diameter of 1.4μm,whereas the resultant composite exhibited a maximum strength of 251 MPa at room temperature and 133 MPa at 350℃,surpassing that of traditional B_(4)C/Al composites.

关键词： Al matrix composites Neutron absorbing materials (B_(4)C+Al_(2)O_(3))/Al composites High-temperature strength

Preparation and Catalysis of Aminomethylated Polystyrene Supported Unsymmetrical Schiff-Base Metal Complexes for the Oxidation of Cyclohexene

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复旦学报（自然科学版） 2007年第5期46卷 809-页

作者： x.l.shi Y.Chang F.Zha Y.G.Wang Key laboratory of Polymer Materials of Gansu Province College of Chemistry and Chemical Engineering Northwest Normal University

1 Results The dominant position of molecular oxygen as the oxidant for bulk chemical oxyfunctionalizations is due to the fact that it is the only economically and environmentally friendly feasible oxidant for large scale *** molecular oxygen is not better oxidant than others,such as PhIO,NaOCl,H2O2,alkyl hydroperoxides,percarboxylic acids,magnesium *** we have to select high reactivity and general utility *** oxidation of hydrocarbons catalyzed by transition metal ...

关键词： Schiff-base unsymmetry complexes catalysis

Interplay of RNA-binding proteins controls germ cell development in zebrafish

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Journal of Genetics and Genomics 2024年第9期51卷 889-899页

作者： De-li shi laboratory of Developmental Biology CNRS-UMR7622Institut de Biologie Paris-Seine(IBPS)Sorbonne University75005 ParisFrance

The specification of germ cells in zebrafish mostly relies on an inherited mechanism by which localized maternal determinants,called germ plasm,confer germline fate in the early *** studies have partially allowed the identification of key regulators governing germ plasm formation and subsequent germ cell ***-binding proteins,acting in concert with other germ plasm components,play essential roles in the organization of the germ plasm and the specification,migration,maintenance,and differentiation of primordial germ *** loss of their functions impairs germ cell formation and causes sterility or sexual *** is emerging that they instruct germline development through differential regulation of mRNA fates in somatic and germ ***,the challenge remains to decipher the complex interplay of maternal germ plasm components in germ plasm compartmentalization and germ cell *** failure to control the developmental outcome of germ cells disrupts the formation of gametes,it is important to gain a complete picture of regulatory mechanisms operating in the germ cell *** review sheds light on the contributions of RNA-binding proteins to germ cell development in zebrafish and highlights intriguing questions that remain open for future investigation.

关键词： Germplasm Primordialgerm cell Germlinestem cell Gametogenesis Zebrafish RNA-binding protein Posttranscriptional gene expression Translational activation and repression

A DiscreteMulti-Objective Squirrel Search Algorithm for Energy-Efficient Distributed Heterogeneous Permutation Flowshop with Variable Processing Speed

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Computers, Materials and Continua 2024年第1期81卷 1757-1787页

作者： Zeng l. Ding Z. shi J. Wang S. School of Electrical and Electronic Engineering Hubei University of Technology Wuhan 430068 China Hubei Key laboratory for High-Efficiency Utilization of Solar Energy and Operation Control of Energy Storage System Hubei University of Technology Wuhan 430068 China xiangyang Industrial Institute of Hubei University of Technology Xiangyang 441100 China

In the manufacturing industry, reasonable scheduling can greatly improve production efficiency, while excessive resource consumption highlights the growing significance of energy conservation in production. This paper studies the problem of energy-efficient distributed heterogeneous permutation flowshop problem with variable processing speed (DHPFSP-VPS), considering both theminimum makespan and total energy consumption (TEC) as objectives. A discrete multi-objective squirrel search algorithm (DMSSA) is proposed to solve the DHPFSPVPS. DMSSA makes four improvements based on the squirrel search algorithm. Firstly, in terms of the population initialization strategy, four hybrid initialization methods targeting different objectives are proposed to enhance the quality of initial solutions. Secondly, enhancements are made to the population hierarchy system and position updating methods of the squirrel search algorithm, making it more suitable for discrete scheduling problems. Additionally, regarding the search strategy, six local searches are designed based on problem characteristics to enhance search capability. Moreover, a dynamic predator strategy based on Q-learning is devised to effectively balanceDMSSA's capability for global exploration and local exploitation. Finally, two speed control energy-efficient strategies are designed to reduce TEC. Extensive comparative experiments are conducted in this paper to validate the effectiveness of the proposed strategies. The results of comparing DMSSA with other algorithms demonstrate its superior performance and its potential for efficient solving of the DHPFSP-VPS problem. © 2024 The Authors. Published by Tech Science Press.

关键词： Distributed heterogeneous permutation flowshop problem energy-efficient squirrel search algorithm muli-objective optimization variable processing speed

Competitive interactions and coexistence of sympatric flagship carnivores in Asia

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Integrative Zoology 2024年第2期19卷 183-199页

作者： Zhilin lI Jiayu lU xiaoyi shi li’an DUO James l.D.SMITH Tianming WANG Tianjin Key laboratory of Conservation and Utilization of Animal Diversity College of Life SciencesTianjin Normal UniversityTianjinChina Department of Fisheries Wildlife and Conservation BiologyUniversity of MinnesotaSt.PaulMinnesotaUSA Ministry of Education Key laboratory for Biodiversity Science and Engineering College of Life SciencesBeijing Normal UniversityBeijingChina National Forestry and Grassland Administration Key laboratory for Conservation Ecology of Northeast Tiger and leopard BeijingChina

Understanding the competition and coexistence of flagship carnivores is key to creating strategies for their conservation in the face of global carnivore *** studies exploring the dynamics and competition between tigers(Panthera tigris)and leopards(***)span decades,there is a lack of understanding regarding the factors that influence their coexistence mechanisms on a broad scale,as well as the drivers determining their exploitative and interference *** gathered a comprehensive list of research papers among which 36 papers explored the interspecific interactions between tigers and leopards and tested the influence of biotic and abiotic factors on the coexistence mechanisms along three dimensions using multiple response variables regression models;we also tested the influence of ecological drivers determining the exploitative or interference competition between tigers and *** and ungulate density were the most important predictors in regulating the coexistence *** and leopards exhibited more positive relations/higher overlaps as elevation increased in the spatial *** addition,they showed a higher dietary overlap in the prey-rich *** determined that interference competition between tigers and leopards was less frequently observed in habitats with dense tree cover and homogeneous vegetation ***,studies with multiple metrics would promote the detection of interference *** study provides new insight into the competitive interactions and coexistence mechanisms of tigers and leopards on a broad ***-makers and managers should pay more attention to the factors of elevation,prey abundance,and habitat structures for the conservation of tigers and leopards.

关键词： carnivores coexistence mechanisms competitive interactions exploitative competition interference competition