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Development of a MWDC prototype of the CSR external-target experiment

Nuclear Science and Techniques 2024年第10期35卷 121-134页

作者： Zhou-Bo He Zhi qin Peng Ma He-Run Yang Xiang-Lun wei Chen-Gui Lu Xiang-Jie Wen Xiu-Ling Zhang Tao Chen Zhi-Jie Li Yuan-Sheng Yang Mei-Qiang Zhan Can-Wen Liu Meng Li Tian-Li Qiu Yi-wei Gong Xin-Jie Huang Xiao-Hao Yin Zhi-Xuan He Jun-wei Zhang Hai-Chuan Zou Sheng-wei Fu Dong Guo Jun-wei Yan Zhe Cao Zhi Deng Jie Kong Zhi-Gang Xiao Rong-Jiang Hu Li-Min Duan Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Department of Physics Tsinghua UniversityBeijing 100084China University of Science and Technology of China Hefei 230026China Key Laboratory of Radiation Physics and Technology of the Ministry of Education Institute of Nuclear Science and TechnologySichuan UniversityChengdu 610064China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China North China University of Water Resources and Electric Power Zhengzhou 450000China

The cooling storage ring(CSR)external-target experiment(CEE)is a spectrometer used in construction to study the properties of nuclear matter in high-baryon density regions at the Heavy-Ion Research Facility in Lanzhou(HIRFL).This study presents the design,simulation,manufacturing,and testing of a half-size prototype of a multi-wire drift chamber(MWDC)for the ***,the performance of the MWDC connected to homemade electronics was *** results demonstrated that an energy resolution of 18.5% for 5.9-keV X-rays and a position resolution of 194μm for protons can be achieved by the current *** the size of the largest MWDC reached 176 cm×314 cm,a set of 98 cm×98 cm prototypes was built using the new *** positioning accuracy of the anode wires in this prototype is better than 20μ*** optimization,using commercially available electronics,the prototype can achieved an energy resolution of 19.7%for a^(55)Fe X-ray *** CEE-MWDC detector and electronics were simultaneously *** energy resolution of 22%was achieved for the^(55)Fe source;the track residuals were approximately 330μm for the cosmic *** results demonstrate that the current design and techniques meet the requirements of the CEE-MWDC array.

关键词： CEE MWDC Garfield++ ^(55)Fe source Position resolution

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一种高效的F-x域快速Radon变换方法

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物探化探计算技术 2009年第3期31卷 218-222页

作者：秦臻姚姚张才中国石油勘探开发研究院北京100083 中国地质大学地球物理与空间信息学院湖北武汉430074

Radon变换是地球物理数据处理中的重要方法之一,传统的Radon变换有t-x法、F-K法和F-x法。与目前发展起来的方法比较,传统方法具有稳定性高和容易实现的优势,在实际的资料处理中仍占有重要的位置。在这三种传统方法中,t-x法和F-K法由于... 详细信息

Radon变换是地球物理数据处理中的重要方法之一,传统的Radon变换有t-x法、F-K法和F-x法。与目前发展起来的方法比较,传统方法具有稳定性高和容易实现的优势,在实际的资料处理中仍占有重要的位置。在这三种传统方法中,t-x法和F-K法由于涉及到插值,所以不可避免地存在误差;F-x法不需插值,计算精度较高,但是由于存在着大量的复数运算,所以影响了计算效率。这里针对F-x域Radon变换的数据计算特征,把矩阵与向量相乘改写为向量与向量卷积的形式,并利用快速傅立叶变换(FFT)来实现快速卷积运算,提高了F-x法的计算效率。

关键词： Radon变换快速傅立叶变换快速卷积

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Increased precipitation magnifies the effects of N addition on performance of invasive plants in subtropical native communities

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Journal of Plant Ecology 2022年第3期15卷 473-484页

作者： Xiang-qin Li Sai-Chun Tang Yu-Mei Pan Chun-Qiang wei Shi-Hong Lü Guangxi Key Laboratory of Plant Conservation and Restoration Ecology in Karst Terrain Guangxi Institute of BotanyGuangxi Zhuang Autonomous Region and Chinese Academy of SciencesGuilin 541006China Zhejiang Provincial Key Laboratory of Plant Evolutionary Ecology and Conservation Taizhou UniversityTaizhou 318000China

Nitrogen(N)deposition,precipitation and their interaction affect plant invasions in temperate ecosystems with limiting N and water resources,but whether and how they affect plant invasions in subtropical native communities with abundant N and precipitation remains *** constructed in situ artificial communities with 12 common native plant species in a subtropical system and introduced four common invasive plant species and their native counterparts to these *** compared plant growth and establishment of introduced invasive species and native counterparts in communities exposed to ambient(CK),N addition(N+),increased precipitation(P+)and N addition plus increased precipitation(P+N+).We also investigated the density and aboveground biomass of communities under such conditions.P+alone did not enhance the performance of invasive species or native counterparts.N+enhanced only the aboveground biomass and relative density of invasive species.P+N+enhanced the growth and establishment performance of both invasive species and native *** growth and establishment parameters of invasive species were greater than those of native counterparts under N+,P+and P+N+*** density and aboveground biomass of native communities established by invasive species were significantly lower than those of native communities established by native counterparts under P+N+*** results suggest that P+may magnify the effects of N+on performance of invasive species in subtropical native communities where N and water are often abundant,which may help to understand the effect of global change on plant invasion in subtropical ecosystems.

关键词： community aboveground biomass community density growth and establishment increased precipitation invasive plants nitrogen addition subtropical native communities

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Identification of Dian Ji Xue Teng(Kadsura interior) with DNA barcodes

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World Journal of Traditional Chinese Medicine 2017年第1期3卷 11-15页

作者： Hao-Jie Guo Xi-Wen Li yao-Dong Qi Xue-Ping wei Ben-Gang Zhang Hai-Tao Liu Institute of Medicinal Plant Development Chinese Academy of Medical Sciences and Peking Union Medical College Institute of Chinese Materia Medica China Academy of Chinese Medical Sciences

Objective: To identify Kadsura interior(Dian Ji Xue Teng, Schisandraceae) by using DNA ***: We analyzed five DNA barcodes(ITS, ITS2, psb A-trn H, mat K and rbc L) using DNA barcoding in terms of distance-based,tree-based and character-based identification to distinguish Kadsura interior and its ***: In distance-based and tree-based identification, K. interior could be distinguished easily from the species of Schisandra and K. *** character-based identification, there are two single nucleotide polymorphisms(SNPs) in ITS and one SNP in psb A-trn H which can be used to distinguish K. interior from K. heteroclita and K. ***: The results indicate that DNA barcoding can be used to identify K. interior. ITS and psb A-trnH sequence can be the most ideal DNA barcode for discriminating K. interior and its adulterants by the combination analysis of distance-based, tree-based and character-based identification(SNPs).

关键词： DNA barcoding Schisandraceae SNP Kadsura interior

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知识型员工工作家庭冲突对创造力的影响——一个被调节的中介效应模型

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东北大学学报（自然科学版） 2020年第5期41卷 747-752,760页

作者：张兰霞韦彩云杨钦帅付竞瑶东北大学工商管理学院辽宁沈阳110169

依据资源保存理论和情绪事件理论,以294名知识型员工为样本采集的数据,采用层次回归分析方法,探究了知识型员工工作家庭冲突对其创造力的影响,并验证了工作倦怠的中介作用和情绪智力的调节作用.结果表明:知识型员工工作家庭冲突能够显... 详细信息

依据资源保存理论和情绪事件理论,以294名知识型员工为样本采集的数据,采用层次回归分析方法,探究了知识型员工工作家庭冲突对其创造力的影响,并验证了工作倦怠的中介作用和情绪智力的调节作用.结果表明:知识型员工工作家庭冲突能够显著地负向预测其创造力;工作倦怠在知识型员工工作家庭冲突与创造力间起中介作用;情绪智力不但能够显著地调节工作倦怠对创造力的影响,而且也可调节工作倦怠在工作家庭冲突与创造力间的中介效应,即员工的情绪智力水平越高,工作家庭冲突通过工作倦怠影响员工创造力的间接效应越弱.

关键词：工作家庭冲突工作倦怠创造力情绪智力知识型员工

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基于Petri网结构分析的监控器综合

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自动化学报 2008年第8期34卷 964-971页

作者：吴敏颜钢锋张瑶瑶刘妹琴浙江大学电气工程学院系统科学与工程学系杭州310027

在基于Petri网建模的离散事件系统中,提出利用局部关联信息进行约束转换,并实现Petri网结构监控器综合的方法.对以Parikh矢量约束形式给出的控制规范,不可控不可观变迁会导致约束成为非法约束,分析了不可控变迁的前向关联结构和不可观... 详细信息

在基于Petri网建模的离散事件系统中,提出利用局部关联信息进行约束转换,并实现Petri网结构监控器综合的方法.对以Parikh矢量约束形式给出的控制规范,不可控不可观变迁会导致约束成为非法约束,分析了不可控变迁的前向关联结构和不可观变迁的后向关联结构,利用局部关联变迁实现对不可控和不可观变迁的间接控制,从而将非法矢量约束转换为合法约束,并保证初始控制规范的实现.与基于矩阵的监控器综合方法相比,本文的方法只需利用局部信息,最后通过实例对该方法进行了说明.

关键词：离散事件系统 Petri网监控器综合不可控不可观变迁

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枯草芽孢杆菌微生态制剂的研究进展

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中国畜牧兽医 2013年第11期40卷 217-220页

作者：王苇秦瑶李爽周霞石河子大学动物科技学院新疆石河子832003

微生态制剂具有绿色、环保、无害等诸多优点,其已在食品、医疗、改善环境、动物疾病防控及健康养殖等方面应用。随着人们对动物产品安全性关注程度的增加、自身健康保健意识的提高及对自身生存环境改善的迫切需求,微生态制剂还将拥有更... 详细信息

微生态制剂具有绿色、环保、无害等诸多优点,其已在食品、医疗、改善环境、动物疾病防控及健康养殖等方面应用。随着人们对动物产品安全性关注程度的增加、自身健康保健意识的提高及对自身生存环境改善的迫切需求,微生态制剂还将拥有更广阔的发展空间。作者现对枯草芽孢杆菌作为微生态制剂在动物生态养殖、动物疾病防制、生态环境改善及其他一些领域中的应用进行了综述。

关键词：枯草芽孢杆菌微生态制剂应用研究进展

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海湾型潮汐通道中大型深水港开发的水沙问题研究

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水利学报 2007年第12期38卷 1426-1436页

作者：陆永军季荣耀左利钦黄健维南京水利科学研究院河港研究所水文水资源及水利工程科学国家重点实验室江苏南京210029

正在建设中的我国钢铁基地曹妃甸的前沿深槽属于典型的海湾型潮汐通道,潮流在深槽内基本为东西向的往复流,是维持深槽水深的主要动力;其泥沙的运动受波浪与潮流共同作用,风浪掀沙作用对含沙量场影响明显。针对这类海湾型潮汐通道的波浪... 详细信息

正在建设中的我国钢铁基地曹妃甸的前沿深槽属于典型的海湾型潮汐通道,潮流在深槽内基本为东西向的往复流,是维持深槽水深的主要动力;其泥沙的运动受波浪与潮流共同作用,风浪掀沙作用对含沙量场影响明显。针对这类海湾型潮汐通道的波浪、潮流、泥沙及海床演变的特点,建立了波流共同作用下的二维泥沙数学模型,并进行了2006年冬、夏季大小潮潮流、泥沙的验证。验证结果表明,本海域潮位及15条同步垂线流速、流向、含沙量过程的计算值与实测值吻合良好,矿石码头港池前沿计算的冲淤厚度及其分布趋势与实测值接近。在此基础上,研究了曹妃甸深水港开发引起甸头以南深槽、老龙沟深槽、各港池的流速变化及港池航道内的回淤和台风暴潮引起的骤淤等问题,为论证沿海潮汐通道的保护利用以及港口工业的发展等提供依据。

关键词：波浪潮流泥沙数学模型海湾型潮汐通道深水港

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GaN-based substrates and optoelectronic materials and devices

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Chinese Science Bulletin 2014年第12期59卷 1201-1218页

作者： Guoyi Zhang Bo Shen Zhizhong Chen Xiaodong Hu Zhixin qin Xinqiang Wang Jiejun Wu Tongjun Yu Xiangning Kang Xingxing Fu wei Yang Zhijian Yang Zhizhao Gan State Key Laboratory for Artificial Microstructures and Mesoscopic Physics School of PhysicsPeking University Research Center for Wide Bandgap Semiconductors Peking University

In order to solve the problems of GaN heteroepitaxy on sapphire substrate,some techniques were *** GaN substrates have been made by hydride vapor phase epitaxy(HVPE),laser lift-off(LLO),and chemical mechanical polishing *** bending and cracking in the HVPE growth were partly settled by pulsed flow modulation ***-crystal quality was established for 1.2 mm thick GaN substrate by X-ray diffraction measurement,in which the full width of half maximum values were 72,110 arcsec for(102),(002)peaks.A novel micro-size patterned sapphire substrate(PSS)and a nano PSS were also ***-power vertical structure light emitting diodes(VSLEDs)have been developed by Au–Sn eutectic wafer bonding,homemade micro-area LLO,and light extraction structure *** high-injection-level active region with low temperature GaN sandwiched layers was used for lowefficiency *** light output power of VSLED was achieved as 400 mW driven at 350 mA,and the dominant wavelength is about 460 *** structures and properties of strain modulated superlattices(SLs)and quantum wells as well as advanced simulation of carriers transport across the electron blocking layer were investigated in laser *** hole concentration was achieved as high as1.6 9 1018cm-3in AlGaN/GaN SLs:Mg by inserting an AlN ***-quality AlGaN epilayers and structures were grown by *** device structures of UV LEDs and detectors were *** emission wavelength of 262 nm UV LED has been successfully *** last,high-quality InN and InGaN materials for solar cell were grown by boundary-temperature-controlled epitaxy and growth-temperature-controlled ***-effect measurement showed a recorded electron mobility of 3,280 cm2/(V s)and a residual electron concentration of 1.47 9 1017cm-3at 300 K.

关键词： AlGaN 蓝宝石衬底光电子材料 MOCVD生长氢化物气相外延激光二极管垂直结构器件

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Densification mechanism of stereolithographical dense Si_(3)N_(4) ceramics with CeO_(2) as sintering additive by field assisted sintering

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Journal of Central South University 2021年第4期28卷 1233-1243页

作者： RAO wei-dong LIU yao CHENG Li-jing LIU Shao-jun State Key Laboratory for Powder Metallurgy Central South UniversityChangsha 410083China Shenzhen Research Institute Central South UniversityShenzhen 518007China College of Mechanical and Electronic Engineering Pingxiang UniversityPingxiang 337000China School of Mechanical Engineering Hebei University of TechnologyTianjin 300130China

Combining sintering additive with field assisted sintering,stereolithographical dense Si3N4 ceramics was successfully *** to a large amount of polymer during the stereolithography,the green parts have the characteristics of low powder loading and high *** the process parameters such as sintering temperature and soaking time can effectively improve the density of the *** stress exponent n of all specimens is in a range of 1 and 2,which is derived from a modified sintering kinetics *** apparent activation energy Qd of stereolithographic Si_(3)N_(4) ceramics sintered with applied pressures of 30 MPa,40 MPa,and 50 MPa is 384.75,276.61 and 193.95 kJ/mol,respectively,suggesting that the densification dynamic process is strengthened by raising applied *** grain boundary slipping plays a dominating role in the densification of stereolithographic Si3N4 *** Vickers hardness and fracture toughness of stereolithographic Si3N4 ceramics are HV10/10(1347.9±2.4)and(6.57±0.07)MPaAbstract:Combining sintering additive with field assisted sintering,stereolithographical dense Si3N4 ceramics was successfully *** to a large amount of polymer during the stereolithography,the green parts have the characteristics of low powder loading and high *** the process parameters such as sintering temperature and soaking time can effectively improve the density of the *** stress exponent n of all specimens is in a range of 1 and 2,which is derived from a modified sintering kinetics *** apparent activation energy Qd of stereolithographic Si3N4 ceramics sintered with applied pressures of 30 MPa,40 MPa,and 50 MPa is 384.75,276.61 and 193.95 kJ/mol,respectively,suggesting that the densification dynamic process is strengthened by raising applied *** grain boundary slipping plays a dominating role in the densification of stereolithographic Si3N4 *** Vickers hardness and fracture toughn

关键词： stereolithography silicon nitride ceramics sintering mechanism densification field assisted sintering

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