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Polycrystalline chemical-vapor-deposited diamond for fast and ultra-fast neutron detection

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Science China(Technological Sciences) 2012年第9期55卷 2640-2645页

作者： LIU LinYue OUYANG XiaoPing zhang zhongbing zhang JianFu zhang XianPeng ZHONG YunHong WANG Wei Northwest Institute of Nuclear Technology Xi'an 710024China Xi'an Jiaotong University Xi'an 710049China

An intrinsic sensor （diameter 16 ram, thickness 300 μm ） based on chemical vapor deposition derived polycrystailine diamond was developed. Ultra low dark current under 100 pA and high n/γ discrimination of 15.8 were obtained on this device, which enable it to be used for neutron detection in multi-radiation field. Moreover, the neutron sensitivity of this detector was characterized theoretically and experimentally. And for fast and ultra-fast neutron, the detection sensitivity is in the magnitude of 10^-17 to 10^-16 C cm^2/n with good stability and negligible pump effect. All these results indicate that the as-prepared sensor to be ideal for fast and ultra-fast neutron monitoring, and it may pave the way to build neutron detector with low cost and large sensitive area with diamond.

关键词： neutron detection CVD diamond detector semiconductor

Size-induced effect on cathode luminescence spectra of CsI(Na) and CsI(Tl) crystals

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Science China(Physics,Mechanics & Astronomy) 2014年第9期57卷 1684-1688页

作者： LIU Fang OUYANG XiaoPing LIU Bin LIU JinLiang CHEN Liang zhang zhongbing zhang XueBin FENG Yi Radiation Detection Research Center Northwest Institute of Nuclear Technology School of Nuclear Science and Engineering North China Electric Power University Department of Engineering Physics Tsinghua University School of Materials Science and Engineering Hefei University of Technology

We investigated the cathode luminescence characteristics of CsI(Na)and CsI(Tl)crystals by the spectrum and structure properties at room *** fabricated three different sizes of CsI(Na)and CsI(Tl)crystals and measured their luminescence spectra under cathode *** found that CsI(Na)cathode luminescence peaks appear at 420 and 305 nm,and CsI(Tl)cathode luminescence peaks are 540 and 410 nm,the grain size affects CsI(Na)luminescence significantly,and the Na-related420 nm luminescence intensified relatively when the average grain size reaches^20μm,which becomes weak when the grain size is down to *** the cathode luminescence spectra of CsI(Tl)crystals with different size have no obvious *** explanations for these phenomena are that the different impurities in the same host material CsI lead to different luminescence *** cathode luminescence characteristics indicate the suitability of CsI(Na)and CsI(Tl)crystals to match photomultiplier tube for large area crystal detector development.

关键词： CsI(Na) crystal CsI(Tl) crystal cathode luminescence spectrum

Image reconstruction of a neutron scatter camera

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Science China(Technological Sciences) 2016年第1期59卷 149-155页

作者： zhang XianPeng zhang Mei SHENG Lang zhang zhongbing LI Kui Nian PENG BoDong zhang XiaoDong OUYANG XiaoPing LIU Jun LIU JinLiang CHEN Liang ZHU Jie HE ChaHui School of Nuclear Science and Technology Xi'an Jiaotong University Xi'an 710049China Northwest Institute of Nuclear Technology P.O.Box 69-9Xi'an 710024China

Recently, Sandia Laboratories developed a neutron scatter camera to detect special nuclear materials. This camera exhibits the following advantages: high efficiency, direction discrimination, neutron-gamma discrimination ability, and wide field of view. However, using the direct projection method, the angular resolution of this camera is limited by uncertainties in the energies estimated from pulse height and time of flight measurements. In this study, we established an eight-element neutron scatter camera and conducted the experiment with a ^(252)Cf neutron source. The results show that it has an angular resolution better than 8°(1s) and a detection efficiency of approximately 2.6′10-4. Using maximum likelihood expectation maximization method, the image artifact was eliminated, and the angular resolution was improved. We proposed an average scattering angle method to estimate the scattering energy of neutrons and Compton gamma rays. As such, we can obtain a recognizable image and energy spectrum of the source with some degradation of energy and image resolutions. Finally, a newly measured light response function based on the MPD^(-4) device was used for image reconstruction. Although we did not obtain a better result than that of the standard light response function, we have observed the effects of light response function on image reconstruction.

关键词： neutron scatter camera ^(252)Cf neutron source energy reconstruction image reconstruction maximum likelihood expectation maximization time of flight light response function

Robust adaptive matched field processing with environmental uncertainty

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Chinese Journal of Acoustics 2006年第2期25卷 159-170页

作者： YANG Kunde MA Yuanliang zhang zhongbing ZOU Shixin Institute of Acoustic Engineering Northwestern Polytechnical University Xi'an 710072

The main challenges on detection and localization of quiet targets in littoral regions for passive sonar are the complicated acoustic propagation and the prevalence of loud ship interferences on the surface. Adaptive matched field processing can provide the ability to null surface interferences, but the mismatch between the computed and actual array steering vectors due to environment uncertainty, and the motion of both targets and interferences can result in loss of array gain significantly. To address the problem of environmental mismatch and target motion, a robust motion compensation algorithm and a system scheme for adaptive matched field processing have been developed. Both Numerical simulation and analysis of experimental data demonstrates that the robust AMFP scheme could suppress surface loud interferences and improve the detection performance for underwater weak moving targets in complex shallow water.

关键词： matched field processing simulation and analysis detection performance acoustic propagation motion compensation experimental data moving targets shallow water

Co-Localization of Sampling and Sequencing for Zoonotic Pathogen Identification in the Field Monitoring Using Mobile Laboratories

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China CDC weekly 2022年第12期4卷 259-263,I0007页

作者： Xin Lu Yao Peng Yuanyuan Geng Hongqun Zhao Xiaona Shen Dongmei Li Zhenpeng Li Liang Lu Mengguang Fan Wenbin Xu Jin Wang Lianxu Xia zhongbing zhang Biao Kan State Key Laboratory of Infectious Disease Prevention and Control BeijingChina/National Institute for Communicable Disease Control and PreventionChinese Center for Disease Control and PreventionBeijingChina General Center for Disease Control and Prevention of Inner Mongolia Autonomous Region Huhhot CityInner Mongolia Autonomous RegionChina Siziwang Banner Center for Disease Control and Prevention Huhhot CityInner Mongolia Autonomous RegionChina School of Public Health Shandong UniversityJinan CityShandong ProvinceChina

Introduction:Accurate etiological detection is needed to evaluate the risk of zoonotic *** next-generation sequencing(mNGS)can be used to monitor pathogens in animal species and identify potential zoonotic *** current sampling model for zoonotic pathogen monitoring in wild animals requires samples to be transferred from the field to a laboratory for further ***:We constructed a zoonotic pathogen survey model using a set of mobile ***:The monitoring in this study was preplanned to detect Yersinia pestis,but the mNGS unexpectedly identified Bartonella *** the rodent samples,thus exposing the threat of bartonellosis to humans in this *** co-localization of sampling and sequencing(CLOSS)model we tested required no long-distance transferring of samples and expands the regional coverage of zoonotic surveys by using a mobile ***:Using this mNGS technique will enable detection of more zoonotic pathogens beyond the preplanned monitoring *** may increase the surveillance efficiency compared with that of the previous workflow and expand the application of the mobile laboratories for infectious diseases identification and surveillance in the field.

关键词： enable transferred monitoring

Human Plague Case Diagnosed in Ningxia Tracked to Animal Reservoirs—Inner Mongolia Autonomous Region,China,2021

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China CDC weekly 2021年第52期3卷 1109-1112页

作者： Jianwei Gao Yanhong Hu Cheng Ju Jingyuan Liu Yiting Wang Jiangtao Ma Xiaona Shen Fang Liu Jin Guo Xinxin Yu Wen zhang Shuyi Wang Kun Li zhongbing zhang Biao Kan Wenrui Wang Xianbin Cong Mengguang Fan Wei Li Kuidong Shao Tao zhang Jianyun Li Yumeng Wang Center for Disease Control and Prevention of Ningxia Hui Autonomous Region YinchuanNingxia Hui Autonomous RegionChina General Center for Disease Control and Prevention of Inner Mongolia Autonomous Region HuhhotInner Mongolia Autonomous RegionChina The Base for Control and Prevention of Plague and Brucellosis Chinese Center for Disease Control and PreventionBaichengJilinChina Beijing Ditan Hospital Capital Medical UniversityBeijingChina National Institute for Communicable Disease Control and Prevention Chinese Center for Disease Control and PreventionBeijingChina State Key Laboratory of Infectious Disease Prevention and Control BeijingChina.

Summary What is already known about this topic?There were a total of 4 and 3 human plague cases that occurred in the Inner Mongolia Autonomous Region in 2019 and 2020,respectively,with 1 and 2 deaths in 2019 and 2020 respectively,which indicated that plague still poses a significant threat to human health especially for farmers,shepherds,or residents living in native plague *** is added by this report?On August 14,2021,1 patient from the Otog Qi(County)in the Inner Mongolia sought treatment in Yinchuan City(the capital of Ningxia Hui Autonomous Region).

关键词： Ningxia residents farmers

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兰索拉唑治疗反流性食管炎多中心临床观察

中华消化杂志 1999年第4期19卷 243-245页

作者：许国铭邹多武第二军医大学长海医院

目的探讨兰索拉唑对反流性食管炎的疗效。方法上海地区４所医院用兰索拉唑３０ｍｇ，每日一次，治疗９２例经内镜证实的反流性食管炎患者。分别于治疗后２、４、６周观察反酸、烧心、反食等症状疗效，并于６周后复查胃镜，观察镜下治愈... 详细信息

目的探讨兰索拉唑对反流性食管炎的疗效。方法上海地区４所医院用兰索拉唑３０ｍｇ，每日一次，治疗９２例经内镜证实的反流性食管炎患者。分别于治疗后２、４、６周观察反酸、烧心、反食等症状疗效，并于６周后复查胃镜，观察镜下治愈率，其中１０例患者分别与治疗前、后进行食管２４小时ｐＨ监测。结果兰索拉唑治疗２周，即可见症状明显改善，症状记分较治疗前明显下降（Ｐ＜０．０１），治疗２、４、６周后，症状治疗显效率分别为５３．２６％、８０．４３％及８２．６１％（治疗４周及６周后，与２周比，Ｐ＜０．０１）。治疗６周症状改善总有效率为９３．４８％。６周后Ⅰ级食管炎治愈率为９３．７５％，高于Ⅱ级７５．７６％、Ⅲ级与Ⅳ级６３．６４％（Ｐ＜０．０５）；但各级食管炎改善，即有效率比较差异无显著性。１０例进行食管２４小时ｐＨ监测患者，治疗后，反流总时间百分率及反流总次数分别由１６．３７±５．９３％及１５０．２±３６．５０次，降至４．８１±０．４４％（Ｐ＜０．０１）及５８．１±１６．９９次（Ｐ＜０．０１）。结论兰索拉唑是治疗反流性食管炎的有效药物。

关键词：胃食管反流病反流性食管炎兰索拉唑治疗

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不确定环境下的稳健自适应匹配场处理研究

声学学报 2006年第3期31卷 255-262页

作者：杨坤德马远良张忠兵邹士新西北工业大学航海学院西安710072

针对浅海中由于水声环境参数不确定、水面强干扰的存在、以及目标运动等因素会导致水下弱目标检测与定位性能严重下降的问题,将协方差矩阵降阶、环境宽容性约束和运动补偿进行有机结合,在对运动补偿算法加以改进的基础上,提出了一种在... 详细信息

针对浅海中由于水声环境参数不确定、水面强干扰的存在、以及目标运动等因素会导致水下弱目标检测与定位性能严重下降的问题,将协方差矩阵降阶、环境宽容性约束和运动补偿进行有机结合,在对运动补偿算法加以改进的基础上,提出了一种在不确定环境和强干扰背景下检测水下微弱目标的稳健自适应匹配场处理方案。典型浅海环境下的数值仿真和实测数据分析表明,该方案在一定的环境失配条件下不仅能有效地抑制水面强干扰,还能为水下微弱运动目标的检测提供较大范围的空时相干累积,有利于提高目标的定位精度和输出信干比。

关键词：不确定环境匹配场处理自适应稳健弱目标检测运动补偿算法浅海环境参数不确定协方差矩阵水声环境

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浅谈施工阶段的质量监理

四川水利 2005年第4期26卷 41-42页

作者：张中兵内江蜀能水利电力工程监理中心四川内江641000

在施工阶段推行以动态控制为主,事前预防为辅的管理办法,主要抓住事先指导、事中检查、事后验收三个环节。一切以数据说话,一切以书面为根据,做好提前预控,从预控角度主动发现问题,对重点部位、关键工序进行动态控制。在施工管理过程中... 详细信息

在施工阶段推行以动态控制为主,事前预防为辅的管理办法,主要抓住事先指导、事中检查、事后验收三个环节。一切以数据说话,一切以书面为根据,做好提前预控,从预控角度主动发现问题,对重点部位、关键工序进行动态控制。在施工管理过程中,抓“重点部位”的质量控制,对工程施工做到全过程、全方位的质量监控,从而有效的实现工程项目施工的全面质量控制。

关键词：施工阶段质量监理动态控制全面质量控制工程项目施工管理办法发现问题关键工序管理过程工程施工