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Recent progress on space-borne microwave sounder pre-launch calibration technologies in China

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Journal of Systems Engineering and Electronics 2008年第4期19卷 643-651,658页

作者： nian Feng Yang Yujie Chen Yunmei xu Dezhong Wang Wei National Key Laboratory of Metrology and Calibration Technology Beijing 100854 P. R. China Beijing Inst. of Radio Metrology & Measurement Beijing 100854 P. R. China

The development processes and the application achievements of space-borne microwave sounder pre-launch calibration technologies in China are introduced briefly. Then, the general project plan for pre-launch calibration, the latest research achievements on the optimization and development of the microwave wide band calibration targets, emissivity measurement technologies and the system level uncertainty analysis of the laboratory, and the thermal/vacuum microwave sounder calibration system for ＂FY-3＂ meteorological satellite are reported, respectively. Finally, the key technological problems of the calibration technologies under researching are analyzed predictively.

关键词： microwave sounder calibration uncertainty remote sensing

Effects of sowing date and ecological points on yield and the temperature and radiation resources of semi-winter wheat

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Journal of Integrative Agriculture 2023年第5期22卷 1366-1380页

作者： ZHANG Zhen-zhen CHENG Shuang FAN Peng ZHOU nian-bing XING Zhi-peng HU Ya-jie xu Fang-fu GUO Bao-wei WEI Hai-yan ZHANG Hong-cheng Jiangsu Key Laboratory of Crop Cultivation and Physiology/Innovation Center of Rice Cultivation Technology in Yangtze Valley Ministry of Agriculture and Rural Affairs/Co-Innovation Center for Modern Production Technology of Grain CropsYangzhou UniversityYangzhou 225009P.R.China

Exploring the effects of sowing date and ecological points on the yield of semi-winter wheat is of great *** study aims to reveal the effects of sowing date and ecological points on the climate resources associated with wheat yield in the Rice–Wheat Rotation *** six sowing dates,the experiments were carried out in Donghai and Jianhu counties,Jiangsu Province,China using two semi-winter wheat varieties as the objects of this *** basic seedlings of the first sowing date (S1) were planted at 300×10^(4)plants ha^(-1),which was increased by 10%for each of the delayed sowing dates (S2–S6).The results showed that the delay of sowing date decreased the number of days,the effective accumulated temperature and the cumulative solar radiation in the whole growth *** yields of S1 were higher than those of S2 to S6 by 0.22–0.31,0.5–0.78,0.86–0.98,1.14–1.38,and 1.36–1.59 t ha^(–1),*** a given sowing date,the growth days increased as the ecological point was moved north,while both mean daily temperature and effective accumulative temperature decreased,but the cumulative radiation *** a result,the yields at Donghai County were 0.01–0.39 t ha–1lower than those of Jianhu County for the six sowing *** effective accumulative temperature and cumulative radiation both had significant positive correlations with *** average temperature was significantly negatively correlated with the *** decrease in grain yield was mainly due to the declines in grains per spike and 1 000-grain weight caused by the increase in the daily temperature and the decrease in the effective accumulative temperature.

关键词： wheat yield sowing date ecological point

A new gain-of-function OsGS2/GRF4 allele generated by CRISPR/Cas9 genome editing increases rice grain size and yield

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The Crop Journal 2022年第4期10卷 1207-1212页

作者： Wenshu Wang Weipeng Wang Yanlin Pan Chao Tan Hongjing Li Ya Chen Xingdan Liu Jing Wei nian xu Yu Han Han Gu Rongjian Ye Qi Ding Chonglie Ma Life Science and Technology Center China National Seed Group Co.Ltd.Wuhan 430000HubeiChina State Key Laboratory of Crop Breeding Technology Innovation and Integration China National Seed Group Co.Ltd.Wuhan 430000HubeiChina

Grain size is one of the most important factors affecting rice grain quality and yield,and attracts great attention from molecular biologists and *** this study,we engineered a CRISPR/Cas9 system targeting the miR396 recognition site of the rice GS2 gene,which encodes growth-regulating factor 4(OsGRF4)and regulates multiple agronomic traits including grain size,grain quality,nitrogen use efficiency,abiotic stress response,and seed *** contrast to most previous genome editing efforts in which indel mutations were chosen to obtain null mutants,a mutant named GS2^(E) carrying an in-frame 6-bp deletion and 1-bp substitution within the miR396-targeted sequence was ***2^(E) plants showed increased expression of GS2 in consistent with impaired repression by *** expected,the gain-of-function GS2^(E) mutant exhibited multiple beneficial traits including increased grain size and yield and bigger grain length/width *** grain weight and grain yield per plant of GS2^(E) plants were increased by 23.5%and 10.4%,*** improved traits were passed to hybrids in a semidominant way,suggesting that the new GS2^(E) allele has great potential in rice *** together,we report new GS2 germplasm and describe a novel gene-editing strategy that can be widely employed to improve grain size and yield in *** trait-improvement strategy could be applied to other genes containing miRNA target sites,in particular the conserved miR396-GRF/GIF module that governs plant growth,development and environmental response.

关键词： Genome editing GS2/GRF4 Grain size Yield Rice

A new cyclostellettamine from sponge Amphimedon compressa

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Chinese Chemical Letters 2007年第8期18卷 947-950页

作者： nian Jun xu xue Sun Xiao Jun Yan Key Laboratory of Marine Biotechnology Faculty of Life Science and Biotechnology Ningbo University Ningbo 315211 China

A new compound, 8,8＇-dienecyclostellettamine, was isolated from the marine sponge Amphimedon compressa. Its structure was elucidated by spectroscopic methods including 1D and 2D NMR, UV, IR, ESI-MS, MALDI-MS techniques. It is probably an important precursor of the manzamine alkoids, and also showed vigorous antibacterial activities.

关键词： Amphimedon compressa Antibacterial 8,8'-Dienecyclostellettamine

Evaluation of neutron beam characteristics for D-BNCT01 facility

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Nuclear Science and Techniques 2022年第1期33卷 131-139页

作者： Jun-Yang Chen Jian-Fei Tong Zhi-Liang Hu xue-Fen Han Bin Tang Qian Yu Rui-Qiang Zhang Chong-Guang Zhao Jun xu Shi-nian Fu Bin Zhou Tian-Jiao Liang Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China University of Chinese Academy of Sciences(UCAS) Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China Guangdong-Hong Kong-Macao Joint Laboratory for Neutron Scattering Science and Technology Dongguan 523803China

An accelerator-based Boron Neutron Capture Therapy(AB-BNCT)experimental facility called D-BNCT01 has been recently completed and is currently able to generate a high-intensity neutron beam for BNCTrelated *** this study,we perform several experiments involving water phantoms to validate the Monte Carlo simulation results and analyze the neutron beam *** to our measurements,D-BNCT01 can generate a neutron flux about 1.2×10^(8)n/cm^(2)/s at the beam port using a 5 kW proton *** results also show that the thermal neutron flux depth distribution inside the water phantom is in good agreement with *** conclude that D-BNCT01 may be effectively employed for BNCT research.

关键词： Neutron beam Boron neutron capture therapy Water phantom

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山地城市内涝形成机理及管理策略研究

重庆建筑 2024年第7期23卷 5-9页

作者：马念徐永新吴欢魏静婉李书钺雷锦涛韩璐明仆林同棪国际工程咨询<中国>有限公司重庆401121 西开普大学自然科学学院地球科学系南非开普敦7535

城市化改变了区域水文过程,涉及城市内涝的水安全问题成为城市普遍面临的挑战。该文以城市化水文效应和排水系统替代模型为基础研究了山地城市内涝机理和成因,在此基础上提出了城市内涝管理的总体策略。城市化后安全要求提高而人工的排... 详细信息

城市化改变了区域水文过程,涉及城市内涝的水安全问题成为城市普遍面临的挑战。该文以城市化水文效应和排水系统替代模型为基础研究了山地城市内涝机理和成因,在此基础上提出了城市内涝管理的总体策略。城市化后安全要求提高而人工的排水系统并不能完全替代原有的泄流通道,这一矛盾是城市内涝产生的根源;为管理等级有序的城市雨洪系统,需要根据系统构成、功能定位和等级制定与之相适应的技术标准,采取相适应的技术措施;雨洪管理需要防御性和适应性相结合,同时利用工程措施和非工程管理措施,并引入智慧管理手段以提高城市洪涝韧性。

关键词：山地城市城市内涝城市化水文效应排水系统替代模型形成机理内涝管理城市韧性

Microstructure and tensile properties of A356 alloy with different Sc/Zr additions

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Rare Metals 2021年第9期40卷 2514-2522页

作者： Shou-Peng xu Chun-Sheng Shi Nai-Qin Zhao Chun-nian He School of Materials Science and Engineering and Tianjin Key Laboratory of Composites and Functional Materials Tianjin UniversityTianjin 300350China Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300072China

Addition of rare earth elements for improving the tensile properties of aluminum alloys has attracted great attention. In this study, a systematic analysis on the microstructure and tensile properties of A356–0.13 Ti alloys with different contents of scandium(Sc) and scandium/zirconium(Sc/Zr) after solution and aging treatment process was carried out. The addition of Sc/Zr into A356–0.13 Ti alloys can greatly refine the grain size and modify the deleterious coarse eutectic Si structure and harmful acicular iron-containing phase morphology. As a result, the maximum value of strength(298 MPa) and ductility(elongation of 8.4%) are acquired by co-addition of Sc/Zr after solution and aging treatment process, which indicates that the tensile properties of A356 alloy are greatly enhanced by the synergistic effect of co-addition of Sc/Zr.

关键词： Aluminum alloys Sc/Zr Tensile properties Solution and aging treatment

A Cross-sectional Study Assessing Predictors of Essential Medicines Prescribing Behavior Based on Information-motivation-behavioral Skills Model among County Hospitals in Anhui, China

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Chinese Medical Journal 2015年第21期128卷 2887-2895页

作者： Yun-Wu Zhao Jing-Ya Wu Heng Wang nian-nian Li Cheng Bian Shu-Man xu Peng Li Hua Lu Lei xu Department of Health Services Management Schoo of Health Administration Anhui Medical University Hefei Anhui 230032 China Department of Research Administration Office Fourth Affiliated Hospital of Anhui Medical University Hefei Anhui 230000 China Department of Dean's Office (HW) Department of Research Administration Office (NNL) Department of Medical Affaires (PL) First Affiliated Hospital of Anhu Medical University Hefei Anhui 230022 China Department of Medical Affaires Guangdong Women and Children Hospital Guangzhou Guangdong 510010 China Department of Personnel Anhui Provincial Hospital Hefei Anhui 230001 China Department of Foreign Languages School of Humanities Tianjin University of Finance and Economics Tianjin 300222 China

Background： The self-consciousness and practicality of preferentially prescribed essential medicines （EMs） are not high enough in county hospitals. The purposes of this study were to use the information-motivation-behavioral skills （IM B） model to identify the predictors of essential medicines prescribing behavior （EMPB） among doctors and to examine the association between demographic variables, IMB, and EMPB. Methods： A cross-sectional study was carried out to assess predictive relationships among demographic variables and IM B model variables using an anonymous questionnaire administered in nine county hospitals of Anhui province. A structural equation model was constructed for the I MB model to test the instruments using analysis of moment structures 17.0. Results： A total of 732 participants completed the survey. The average age of the participants was 37.7 ± 8.9 years old （range： 22-67 years old）. The correct rate of information was 90.64%. The average scores of the motivation and behavioral skills were 45.46 a： 7.34 （hundred mark system： 75.77） and 19.92 ± 3.44 （hundred mark system： 79.68）, respectively. Approximately half（50.8%） of respondents reported that the proportion of EM prescription was below 60%. The final revised model indicated a good fit to the data （x^2/df= 4.146, goodness of fit index = 0.948, comparative fit index = 0.938, root mean square error of approximation = 0.066）. More work experience （β = 0.153, P 〈 0.001 ） and behavioral skills （β = 0.449, P 〈 0.001 ） predicted more EMPB. Higher income predicted less information （β = -0.197, P 〈 0.001） and motivation （β =0.204, P 〈 0.001 ）. Behavioral skills were positively predicted by information （β = 0.135, P 〈 0.001 ） and motivation （β = 0.742, P 〈 0.001 ）. Conclusion： The present study predicted some factors of EMPB, and specified the relationships among the model variables. The utilization rate of EM was not high enough. Motivation and behavior skills were crucial factors affecting EMPB. The inf

关键词： China County Hospitals Essential Medicines Information-motivation-behavioral Skills Model PrescribingBehavior Structural Equation Model

Tailoring the photophysical and photovoltaic properties of boron-difluorodipyrromethene dimers

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Chinese Chemical Letters 2017年第4期28卷 875-880页

作者： Wen-xu Liu Jian-nian Yao Chuan-Lang Zhan Beijing National Laboratory of Molecular Science CAS Key Laboratory of PhotochemistryInstitute of ChemistryChinese Academy of SdencesBeijing 100190China

Five boron-difluorodipyrromethene（BODIPY） dimers have been designed and synthesized successfully via acid-catalysed condensation and Pd-catalysed cross-coupling *** structural modification,including verifying the structures of the π-bridges,altering the positions the bridges link（meso-or β-positions）,and regulating the molecular planarity,can modulate the photophysical properties and the aggregation behaviors of the five dimers ***-processed organic solar cells were fabricated to evaluate the photovoltaic properties of these molecules further either as acceptors or *** using as nonfullerene acceptor and blended with the polymer donor of PTB7,an opencircuit voltaic（V_（oc）） of 1.12 and 1.08 V was achieved from the thiophene and benzodithiophene bridged BODIPY dimers,*** V_（oc） is among the top values achieved from the non-fullerene organic solar cells so far.

关键词： BODIPY Nonfullerene acceptor Small molecule donor Photovoltaic cell Solution-processed