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Rapid diagnostic method for transplutonium isotope production in high flux reactors

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Nuclear Science and Techniques 2023年第3期34卷 125-142页

作者： Qing-Quan Pan Qing-fei zhao Lian-Jie Wang Bang-Yang Xia Yun Cai Xiao-Jing Liu School of Nuclear Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610200China

Transplutonium isotopes are scarce and need to be produced by irradiation in high flux ***,their production is inefficient,and optimization studies are *** study analyzes the physical nature of transplutonium isotope produc-tion using ^(252)Cf,^(244)Cm,^(242)Cm,and ^(238)Pu as *** methods based on the Monte Carlo burnup calculation have the limitations of many calculations and cannot analyze the individual energy intervals in detail;thus,they cannot sup-port the refined evaluation,screening,and optimization of the irradiation *** understanding the physical nature and simplifying the complexity of the production process,we propose a rapid diagnostic method for evaluating radiation schemes based on the concepts“single energy interval value(SEIV)”and“energy spectrum total value(ESTV)”.The rapid diagnostic method not only avoids tedious burnup calculations,but also provides a direction for *** optimal irradiation schemes for producing ^(252)Cf,^(244)Cm,^(242)Cm,and ^(238)Pu are determined based on a rapid diagnostic *** irradiation schemes can significantly improve production *** with the initial scheme,the optimal scheme improved the production efficiency of ^(238)Pu by 7.41 times;^(242)Cm,11.98 times;^(244)Cm,65.20 times;and ^(252)Cf,15.08 ***,a refined analysis of transplutonium isotope production is conducted and provides a theoretical basis for improving production efficiency.

关键词： Transplutonium isotope Rapid diagnostic method Production optimization Single energy interval value Energy spectrum total value

Microstructure and mechanical properties of spark plasma sintered Ti–Mo alloys for dental applications

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International Journal of Minerals,Metallurgy and Materials 2014年第5期21卷 479-486页

作者： Xin Lu Bo Sun Teng-fei zhao Lu-ning Wang Cheng-cheng Liu Xuan-hui Qu State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing School of Materials Science and Engineering University of Science and Technology Beijing

Ti-Mo alloys with various Mo contents from 6wt% to 14wt% were processed by spark plasma sintering based on elemental pow- ders. The influence of sintering temperature and Mo content on the microstructure and mechanical properties of the resulting alloys were investigated. For each Mo concentration, the optimum sintering temperature was determined, resulting in a fully dense and uniform microstructure of the alloy. The optimized sintering temperature gradually increases in the range of 1100-1300℃ with the increase in Mo content. The microstructure of the Ti-（6-12）Mo ahoy consists of acicular α phase surrounded by equiaxed grains of 13 phase, while the Ti-14Mo al- loy only contains single 13 phase. A small amount of fine α lath precipitated from 13 phase contributes to the improvement in strength and hardness of the alloys. Under the sintering condition at 1250℃, the Ti-12Mo alloy is found to possess superior mechanical properties with the Vickers hardness of Hv 472, the compressive yield strength of 2182 MPa, the compression rate of 32.7%, and the elastic modulus of 72.1 GPa. These results demonstrate that Ti-Mo alloys fabricated via spark plasma sintering are indeed a perspective candidate alloy for dental applications.

关键词： titanium alloys spark plasma sintering microstructure mechanical properties

Use of anti-tuberculosis drugs among newly diagnosed pulmonary tuberculosis inpatients in China: a retrospective study

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Infectious Diseases of Poverty 2016年第1期5卷 9-14页

作者： fei Huang Hui Zhang Qing Lv Kaori DSato Yan Qu Shitong Huan Jun Cheng fei zhao Lixia Wang National Center for TB control and prevention No 155 Changbai RoadChangping DistrictBeijing 102206China Duke Global Health Institute DurhamNCUSA Bill&Melinda Gates Foundation Beijing officeBeijingChina

Background:China’s national tuberculosis control program(NTP)provides free,first-line anti-tuberculosis(TB)drugs to pulmonary TB *** treatment regimen follows the World Health Organization’s(WHO)*** objective of this paper is to evaluate the current status of anti-TB drug use for newly diagnosed pulmonary TB inpatients treated in prefecture-and county-level designated ***:Three prefecture-level hospitals and nine county-level hospitals were selected for the *** newly diagnosed pulmonary TB inpatient medical records from 2012 were reviewed and doubly examined by two national senior *** rational use of anti-TB drugs was evaluated based on criteria in line with WHO’s ***:Of the 2,060 total treatment regimens for TB,53.1%were found to be rational(1093/2060).The percentages in prefecture-level and county-level hospitals were 50.3%(761/1513)and 60.7%(332/547),*** difference between the two levels of hospitals was statistically significant(Chi-square value=17.44,P<0.01).The percentages of rational treatment regimens for first-time hospitalizations and for two or more hospitalizations were 59.5%(983/1653)and 27.0%(110/407),respectively,with a statistically significant difference(Chi-square value=138.00,P<0.01).The overall use of second-line drugs(SLD)was 54.9%(1131/2060).The percentages for prefecture-level and county-level hospitals were 50.6%(766/1513)and 66.7%(365/547),respectively.A statistically significant difference was found(Chi-square value=42.06,P<0.01).The use of SLD for inpatients hospitalized once and inpatients hospitalized twice or more was 58.4%(966/1653)and 40.5%(165/407),respectively,with a statistically significant difference(Chi-square value=42.26,P<0.01).Conclusions:Half of inpatients might be treated with irrational regimens,and the use of SLD was more appropriately dispensed in city-level hospitals than in county-level *** and guidelines for health personnel,

关键词： Tuberculosis Inpatient Drug Regimen Rationality

Synthesis of amphiphilic tri-block copolymerpoly(vinylpyrrolidone)-b-poly(methyl methacrylate)-b-poly(vinylpyrrolidone) for the modification of polyethersulfone membrane

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Chinese Chemical Letters 2011年第3期22卷 370-373页

作者： Sheng Qiang Nie Fen Ran Chao He Peng fei zhao Xiao Hong Wei Jie Li Chang Sheng zhao College of Polymer Science and Engineering State Key Laboratory of Polymer Materials Engineering Sichuan Universiry Chengdu 610065 China State Key Laboratory of Gansu Advanced Non-Ferrous Metal Materials Lanzhou University of Technology Lanzhou 730050 China

Well-defined amphiphilic tri-block copolymer PVP-b-PMMA-b-PVP was prepared for the first time via successive reversible addition fragmentation chain transfer（RAFT） polymerization using carboxyl-terminated trithiocarbonate as the RAFT *** structure of the copolymer was characterized using FTIR,GPC and ~1H *** block copolymer could be directly blended with polyethersulfone（PES） as a macromolecule additive using N-methyl-2-pyrrolidone（NMP） as the solvent to prepare membranes. The water contact angles for the modified membranes decreased obviously,and therefore,the protein adsorption amount on the membrane surface decreased.

关键词： Polyethersulfone membrane Protein adsorption Surface modification PVP-b-PMMA-b-PVP

Anti-detection technology of cat eye target based on decentered field lens

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Chinese Physics B 2018年第9期27卷 333-337页

作者： Da-Lin Song Jun Chang Yi-fei zhao Ze-Xia Zhang School of Optics and Photonics Beijing Institute of Technology Beijing 100081 China The First Research Institute of the Ministry of Public Security Beijing 100048 China

Optoelectronic imaging equipment is easy to expose to active laser detection devices because of ＂cat eye＂ effect. In this paper, we propose a new structure of optical system to reduce the retroreflector effect of a cat eye target. Decentered field lens structure is adopted in the design without sacrificing imaging quality and clear aperture. An imaging system with±30° field of view is taken for example. The detailed design and simulation results are presented. The results indicate that this kind of optical system can reduce the retroreflection signal substantially and maintain acceptable imaging performance.

关键词： geometric optical design cat eye effect reduction decentered field lens

Constructing orthogonally structured graphene nanointerface on SiC nanowires reinforced carbon/carbon composites to boost mechanical strength and strength retention rate

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Journal of Materiomics 2024年第3期10卷 615-623页

作者： Yao Guo Shouyang Zhang Qiang Song fei zhao Longkang Cong Wei Li Ruimei Yuan State Key Laboratory of Solidification Processing Shaanxi Key Laboratory of Fiber Reinforced Light Composite MaterialsNorthwestern Polytechnical UniversityXi'an 710072China Advanced Interdisciplinary Research Center for Flexible Electronics Academy of Advanced Interdisciplinary ResearchXidian UniversityXi'an 710072China

Carbon/carbon composites with higher mechanical strength and better reliability at elevated tempera-tures are urgently needed to satisfy the practical applications *** nanowires(SiCNWs)modified C/C(SC-CC)composites have attracted an abundance of attention for their excellent mechanical *** further boost the mechanical strengths of composites and maximize the reinforcing efficiency of SiCNWs,we introduce orthogonally structured graphene nanosheets(OGNs)into SC-CC composites,in which OGNs are grafted on the SiCNWs via chemical vapor deposition(CVD)method,forming SC-G-CC *** from the nano-interface effects,uniform stress distribution,strong SiCNWs/PyC interfacial bonding and elevated stress propagation efficiency in the PyC matrix are achieved,thus SC-G-CC composites accomplish brilliant mechanical properties before and after 1,600℃ heat *** temperature rises to 2,100℃,SiCNWs lose efficacy,whereas OGNs with excellent thermal stability continue to play the nano-interface role in the PyC ***,SC-G-CC com-posites show better mechanical performance after 2,100℃ heat treatment,and the mechanical strength retention rate(MSR)of interlaminar shear strength,out-of-plane and in-plane compressive strength of SC-G-CC composites reach 61.0%,55.7%and 55.3%,*** work proposes an alternative thought for maximizing the potentiality of nanomaterials and edifies the mechanical modification of composites.

关键词： SiC nanowires Orthogonally structured graphene nanosheets Carbon/carbon composites Mechanical properties Heat treatment

CSCS:a chromatin state interface for Chinese Spring bread wheat

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aBIOTECH 2021年第4期2卷 357-364页

作者： Xiaojuan Ran Tengfei Tang Meiyue Wang Luhuan Ye Yili Zhuang fei zhao Yijing Zhang National Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyShanghai Institutes for Biological SciencesChinese Academy of Sciences300 Fenglin RoadShanghai 200032China University of the Chinese Academy of Sciences Beijing 100049China School of Life Science Henan UniversityKaifeng 457000HenanChina

A chromosome-level genome assembly of the bread wheat variety Chinese Spring(CS)has recently been ***-wide identification of regulatory elements(REs)responsible for regulating gene activity is key to further mechanistic *** epigenetic activity can reflect RE activity,defining chromatin states based on epigenomic features is an effective way to detect ***,we present the web-based platform Chinese Spring chromatin state(CSCS),which provides CS chromatin signature *** indudes 15 recently published epigenomic data sets including open chromatin and major chromatin marks,which are further partitioned into 15 distinct chromatin *** curates detailed information about these chromatin states,with trained self-organization mapping(SOM)for segments in all chromatin states and JBrowse visualization for genomic regions or *** analysis for genomic regions or genes,GO analysis for genes and SOM analysis for new epige-nomic data sets are also integrated into *** summary,the CSCS database contains the combina-torial patterns of chromatin signatures in wheat and facilitates the detection of functi onal elements and further clarification of regulatory *** illustrate how CSCS enables biological insights using one example,demonstrating that CSCS is a highly useful resource for intensive data *** is available at http://***/CSCS/.

关键词： Bread wheat Chinese Spring Chromatin state Epigenetics Database

Dynamic strain field for granite specimen under SHPB impact tests based on stress wave propagation

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Underground Space 2022年第5期7卷 767-785页

作者： Jiong Wang Lei Ma fei zhao Bangguo Lv Weili Gong Manchao He Peng Liu State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and Technology(Beijing)Beijing 100083China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 100083China College of Geosciences and Engineering North China University of Water Resources and Electric PowerZhengzhou 450045China

The full-field strain of rock material under dynamic compression load was studied using the high-speed three dimensional digital image correlation(3D-DIC)*** dynamic test was conducted on Laizhou granite using a split Hopkinson pressure bar(SHPB)*** propagation,dispersion and radial inertial effect on the specimen were found by DIC results.A recovery of strain in the post-peak stage was detected on the specimen by DIC,which was unrevealed in the traditional one-dimensional theory *** can be found that the strain measured by strain gauge was a calculated average one,whereas the strain measured by 3D-DIC could reflect more variation ***,the testing principle with impact loads and rock dynamic behavior was re-examined using stress wave propagation *** theoretical results showed that the specimen reached equilibrium after a series of wave reflections and transmissions and its stress was infinitely close to the initial value of 109.2 ***,the specimen had the calculated maximum strain of 0.52% and strain rate of 15.11 s^(-1),improving the reasonable agreement with the experimental results and requirements of rock mechanical properties measured by SHPB technology.

关键词： SHPB Full-field measurement 3D-DIC Dynamic tests Stress wave propagation

The Current Status and Challenges Regarding Tuberculosis Infection Control in Health Care Facilities in China

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Biomedical and Environmental Sciences 2015年第11期28卷 848-854页

作者： zhao fei CHENG Jun CHENG Shi Ming ZHANG Hui zhao Yan Lin ZHANG Can You HU Dong Mei FAN Hai Ying HUANG fei QU Yan HE Guang Xue WANG Li Xia National Center for Tuberculosis Control and Prevention Chinese Center for Disease Control and Prevention Science and Technology Department Chinese Center for Disease Control and Prevention

Health care facilities are a high-risk environment for generating and spreading respiratory infectious diseases such as tuberculosis （TB）. The TB prevention and treatment staff in health care facilities are responsi... 详细信息

关键词： TB The Current Status and Challenges Regarding Tuberculosis Infection Control in Health Care Facilities in China