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Effects of film mulching regime on soil water status and grain yield of rain-fed winter wheat on the Loess Plateau of China

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Journal of Integrative Agriculture 2017年第11期16卷 2612-2622页

作者： XUE Nai-wen XUE Jian-fu yang Zhen-ping SUN Min ren Ai-xia GAO Zhi-qiang College of Agronomy Shanxi Agricultural University Taigu 030801 P.R. China

Shortages and fluctuations in precipitation are influential limiting factors for the sustainable cultivation of rain-fed winter wheat on the Loess Plateau of China. Plastic film mulching is one of the most effective water management practices to improve soil moisture, and may be useful in the Loess Plateau for increasing soil water storage. A field experiment was conducted from July 2010 to June 2012 on the Loess Plateau to investigate the effects of mulching time and rates on soil water storage, evapotranspiration （ET）, water use efficiency （WUE）, and grain yield. Six treatments were conducted：（1） early mulching （starting 30 days after harvest） with whole mulching （EW）; （2） early mulching with half mulching （EH）; （3） early mulching with no mulching （EN）; （4） late mulching （starting 60 days after harvest） with whole mulching （LW）; （5） late mulching with half mulching （LH）; and （6） late mulching with no mulching （LN）. EW increased precipitation storage efficiency during the fallow periods of each season by 18.4 and 17.8%, respectively. EW improved soil water storage from 60 days after harvest to the booting stage and also outperformed LN by 13.8 and 20.9% in each growing season. EW also improved spike number per ha by 13.8 and 20.9% and grain yield by 11.7 and 17.4% during both years compared to LN. However, EW decreased WUE compared with LN. The overall results of this study demonstrated that EW could be a productive and efficient practice to improve wheat yield on the Loess Plateau of China.

关键词： soil water status plastic film mulching precipitation storage efficiency winter wheat the Loess Plateau

A Defect Detection Method for the Primary Stage of Software Development

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Computers, Materials & Continua 2023年第3期74卷 5141-5155页

作者： qiang Zhi Wanxu Pu Jianguo ren Zhengshu Zhou School of Computer Science and Technology Jiangsu Normal UniversityXuzhou221116China Graduate School of Informatics Nagoya UniversityNagoya4648601Japan

In the early stage of software development,a software requirements specification(SRS)is essential,and whether the requirements are clear and explicit is the ***,due to various reasons,there may be a large number of *** generate high-quality software requirements specifications,numerous researchers have developed a variety of ways to improve the quality of *** this paper,we propose a questions extraction method based on SRS elements decomposition,which evaluates the quality of SRS in the form of numerical *** proposed method not only evaluates the quality of SRSs but also helps in the detection of defects,especially the description problem and omission defects in *** verify the effectiveness of the proposed method,we conducted a controlled experiment to compare the ability of checklist-based review(CBR)and the proposed method in the SRS *** CBR is a classicmethod of reviewing SRS *** a lot of practice and improvement for a long time,CBR has excellent review ability in improving the quality of software requirements *** experimental results with 40 graduate studentsmajoring in software engineering confirmed the effectiveness and advantages of the proposed ***,the shortcomings and deficiencies of the proposed method are also observed through the ***,the proposed method has been tried out by engineers with practical work experience in software development industry and received good feedback.

关键词： Computer science software engineering requirement engineering software quality defect detection

Visible-light-induced direct hydrodifluoromethylation of alkenes with difluoromethyltriphenylphosphonium iodide salt

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Chinese Chemical Letters 2023年第1期34卷 322-325页

作者： Xiaojian ren qiang Liu Zhixiang Wang Xiangyu Chen School of Chemical Sciences University of the Chinese Academy of SciencesBeijing 100049China

Photoredox-catalyzed hydrodifluoromethylation of alkenes has become an effective method to introduce difluoromethyl group into organic *** the reported methods involve either photocatalysts or superstoichiometric amounts of additives,we herein describe a simple alternative without using photocatalyst or additive for the hydrodifluoromethylation of alkenes,through photoactivation of difluoromethyltriphenylphosphonium iodide *** studies shed light on how the transformation takes place.

关键词： Hydrodifluoromethylation Difluoromethyltriphenylphosphonium iodide salt Alkenes DFT studies Photoredox

Preface: Key technologies for enhancing the performance of FAST

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Research in Astronomy and Astrophysics 2020年第5期20卷 63-64页

作者： Peng Jiang Zhi-qiang Shen ren-Xin Xu CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Department of Radio Science and Technology Shanghai Astronomical ObservatoryShanghai 200030China School of Physics and Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China

The Five-hundred-meter Aperture Spherical radio Telescope(FAST)passed its national acceptance inspection on 2020 January *** special issue includes a total of 15 papers,which are selected to introduce the status of FAST’s performance and demonstrate the key technologies applied to *** presented performance parameters can provide an important reference for scientists to propose observations with *** key technologies presented in these papers include design and implementation in the measurement and control system,electromagnetic compatibility system,and receiver ***,scientific achievements obtained by FAST during the commissioning phase are also reported.

关键词： telescope techniques:radar astronomy methods:data analysis methods:observational techniques:interferometric

MoS2 as a long-life host material for potassium ion intercalation

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Nano Research 2017年第4期10卷 1313-1321页

作者： Xiaodi ren qiang Zhao William D. McCulloch Yiying Wu Department of Chemistry and Biochemistry The Ohio State University 151 W Woodruff Ave Columbus OH 43210 USA College of Chemical Engineering Sichuan University Chengdu 610065 China

Electrochemical potassium ion intercalation into two-dimensional layered MoS2 was studied for the first time for potential applications in the anode in potassium-based batteries. X-ray diffraction analysis indicated that an intercalated potassium compound, hexagonal K0.4MoS2, formed during the intercalation process. Despite the size of K^＋, MoS2 was a long-life host for repetitive potassium ion intercalation and de-intercalation with a capacity retention of 97.5% after 200 cycles. The diffusion coefficient of the K^＋ ions in KxMoS2 was calculated based on the Randles-Sevcik equation. A higher K^＋ intercalation ratio not only encountered a much slower K^＋ diffusion rate in MoS2, but also induced MoS2 reduction. This study shows that metal dichalcogenides are promising potassium anode materials for emerging K-ion, K-O2, and K-S batteries.

关键词： potassium ion intercalation potassium battery MoS2 phase evolution potassium ion diffusion

Analysis of the Load-Stress Response Characteristics of the Bogie Frame in Intercity Electric Multiple Unit

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Chinese Journal of Mechanical Engineering 2018年第2期31卷 227-237页

作者： Hua Zou Shou-Guang Sun qiang Li Zun-Song ren Engineering Research Center of Structure Reliability and Operation Measurement Technology of Rail Guided Vehicles of Ministry of Education Beijing Jiaotong University

Load spectra research for bogie frame requires establishing the load?stress relationship on working condition, which has been omitted by the researchers. With the load?stress of the bogie frame of an intercity Electric Multiple Unit(Hereinafter referred to as EMU) as the research object, an optimization model of the load?stress transfer relationship is established. The load?stress coe cient for EMU bogie frame was calibrated in the laboratory bench and online test was arranged on Dazhou?Chengdu line. Comparison of nonlinear and linear neural networks proves that the linear transitive relation between the load and stress of the bogie frame in the operating process is highly suitable. An optimization model of the load?stress transfer coe cient is obtained. The data calculated with the modified coe cient are closer to the dynamic stress results in the actual operating process than the data calculated with the calibration coe cient. The coe cient of the modified transitive relation is una ected by operating area, empty load, heavy load, or other conditions in the operating process of the intercity EMU. The real loads in actual situations are obtained. The model of online load?stress relationship that is highly suitable for line stress calculation is finally established. The research is helpful for further damage calculation and inferring the time history signal of the load in load spectra research.

关键词： Bogie frame Load Stress Transitive relation Neural network

Identification of a Reliable DFT Calculation Method to Predict the Ground-and Excited-State Properties of Nickel(Ⅱ) Complexes with Porphyrin in Crude Oil

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China Petroleum Processing & Petrochemical Technology 2023年第4期25卷 106-116页

作者： Pu Ning ren qiang Hu Dawei Fang Wei yang Qinghe Wang Zhen Hu Anpeng Xu Lei Ge Xin SINOPEC Research Institute of Petroleum Processing Co. Ltd.Beijing 100083China Institute of Nuclear Agricultural Sciences Key Laboratory of Nuclear Agricultural Sciences of Ministry of Agriculture and Zhejiang ProvinceZhejiang UniversityHangzhou 310058China SINOPEC Geophysical Research Institute Nanjing 211103China

Metalloporphyrins have devastating effects on the deep processing and efficient utilization of petroleum resources. Various porphyrins are derived from porphin by substitution at the β, meso, or both positions. Herein, we focus on the interaction between nickel(Ⅱ) and the porphyrin skeleton. Five different density functionals were selected for determining a reliable approach to simulate porphyrin-nickel(Ⅱ) complexes. At D4h symmetry, the 10b1g, 15a1g, 4e1g and 9b2g were dominated by the 3d character of nickel. Compared with pure density functional, the hybrid functional gave larger highest occupied molecular orbital(HOMO) and lowest unoccupied molecular orbital(LUMO) gap, and the higher HOMO-LUMO gap also corresponded to a higher excitation energy. The characteristic Soret and Q bands modeled by timedependent density functional theory(TDDFT) calculations matched well with experimental results, and the absorption was discussed in detail with natural transition orbitals(NTO) analysis. Furthermore, the binding character of nickel(Ⅱ) with various substituted porphyrins were calculated at perdew-burke-ernzerhof(PBE) level, showed that the geometry and complexation behavior of porphyrin-nickel(Ⅱ) complexes could be significantly tuned by different substituents. The symmetry of the complex was reduced and the skeleton ring get distortion when introducing different substituents. Compared with ETIO porphyrin, the introduction of phenyl on the β position can expand the conjugated system and promote the covalent character of Ni-N bond.

关键词： porphyrin-nickel(Ⅱ) DFT/TDDFT binding character spectroscopic properties substituent effect

Carbon dots based on targeting unit inheritance strategy for Golgi apparatus-targeting imaging

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Frontiers of Materials Science 2023年第1期17卷 129-139页

作者： Yingying Wei Yuduan Gao Lin Chen qiang Li Jinglei Du Dongming Wang Fanggang ren Xuguang Liu Yongzhen yang Interventional Treatment Department Second Hospital of Shanxi Medical University(Second Clinical Medical College of Shanxi Medical University)Taiyuan 030001China OphthalmologyDepartment Shanxi Bethune HospitalShanxi Academy of Medical SciencesTongji Shanxi HospitalThird Hospital of Shanxi Medical UniversityTaiyuan 030032China Tongji Hospital Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Key Laboratory of Interface Science and Engineering in Advanced Materials(Ministry of Education) Taiyuan University of TechnologyTaiyuan030024China Key Laboratory of Molecular Diagnosis and Treatment of Blood Diseases of Shanxi Province Second Hospital of Shanxi Medical UniversityTaiyuan030001China Orthopedics Department Second Hospital of Shanxi Medical UniversityTaiyuan 030001China Institute of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China

The Golgi apparatus is one of the important organelles,where the final processing and packaging of cellular secretions(such as proteins)are *** disorder of Golgi apparatus structure and function will induce many ***,monitoring the morphological structure of Golgi apparatus is crucial for the diagnosis and treatment of relevant *** order to achieve Golgi apparatus-targeting imaging,the strategy of targeting unit inheritance was adopted and carbon dots(CDs)with Golgi apparatus-targeting ability were synthesized by one-step hydrothermal method with L-ascorbic acid with high reactivity and reducibility as the carbon source and L-cysteine as the targeting *** have a certain amount of cysteine residues on their surface,and have excitation dependence,satisfactory fluorescence and cysteine residues stability and low *** an imaging agent,CDs can be used for targeting imaging of Golgi apparatus.

关键词： carbon dot Golgi apparatus targeting imaging

Pancreatic cancer with gastrointestinal obstruction as an initial symptom

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 545-547页

作者： Jia-ren Xu Xing-Nan Wu Yong-qiang Si Jin-Pu yang Xiao-Sun Liu Department of Gastrointestinal Surgery the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Department of Gastroenterology the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China

To the Editor: Pancreatic cancer is the fourth leading cause of cancer mortality in the United States [ 1, 2 ]. Risk factors of pancreatic cancer include smoking, family history of chronic pancreatitis, advanced age, male, diabetes mellitus, and obesity [1]. Most of patients have no obvious symptoms in the early stage, and are often diagnosed in the late stage and accompanied by invasion of surrounding tissues and distant metastasis, such as local lymph nodes, liver, lung and peritoneum [ 1, 3 ]. Therefore, the prognosis is poor.

关键词： cancer Pancreatic invasion