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Photosynthetic performance of switchgrass and its relation to field productivity：A three-year experimental appraisal in semiarid Loess Plateau

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Journal of Integrative Agriculture 2017年第6期16卷 1227-1235页

作者： GAO zhi-juan LIU Jin-biao AN qin-qin WANG zhi CHEN Shao-lin XU Bing-cheng State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F University Yangling 712100 P. R. China Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources Yangling 712100 P. R. China College of Life Science Northwest A&F University Yangling 712100 P.R. China

To reveal photosynthetic characteristics and biomass yield is important for evaluating introduced species adaptation to local environments. A field experiment was conducted over three consecutive years（2011–2013） to evaluate photosynthetic characteristics, soil water content, aboveground biomass accumulation, and water use efficiency（WUE） in switchgrass（Panicum virgatum L.） populations exposed to three row spacing（20, 40 and 60 cm） treatments in two growth months（June and August） on the semiarid Loess Plateau of China. Results indicated that net photosynthetic rate（Pn）, transpiration rate（Tr）, instantaneous water use efficiency（WUEi） and plant height of switchgrass showed an increased trend, but aboveground biomass production and WUE showed an decreased trend with enlarged row spacings over the three years. The maximum daily mean Pn values（17.9, 18.4 and 19.7 μmol CO2 m^（-2） s^（-1）） were observed in 2011, and the highest aboveground biomass production（67 771.8, 6 976.8 and 6 609.2 kg ha^（-1）） were recorded in 2012 for 20, 40 and 60 cm, respectively. A close correlation between tiller numbers and aboveground biomass production（r=0.907） was observed. Pn was positively and significantly correlated with biomass per tiller, but it showed a negative correlation with aboveground biomass production. Our results confirm that wide row spacing is beneficial for single plant development, while narrow row spacing favors biomass production and water use of switchgrass in the region. It also implies that single leaf growth and performance could explain the switchgrass community density differences, while fails to account for the aboveground biomass production.

关键词： switchgrass photosynthesis row spacing biomass production water use efficiency

A note on the perturbed monomial mapping

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Applied Mathematics(A Journal of Chinese Universities) 2019年第1期34卷 76-81页

作者： QU cheng-qin ZHU zhi-wei ZHOU Zuo-ling Department of Applied Mathematics South China University of Technology School of Mathematics and Statistics Zhaoqing University Lingnan College Sun Yat-sen University

In this paper, we present a necessary and suffcient condition that the perturbed monomial mapping is ergodic on a sphere S_(p-1)(1), which is in a combination with Anashin's earlier results about the perturbed monomial ergodic mappings on a sphere S_(p-r)(1), r > 1, completely solve a problem posed by A. Khrennikov about the ergodicity of a perturbed monomial mapping on a sphere.

关键词： perturbed monomial mapping ergodic p-adic integers

Experimental Study on Wear Performance and Oil Film Characteristics of Surface Textured Cylinder Liner in Marine Diesel Engine

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Chinese Journal of Mechanical Engineering 2018年第3期31卷 158-167页

作者： zhi-Wei Guo cheng-qing Yuan Xiu-qin Bai Xin-Ping Yan Reliability Engineering Institute National Engineering Research Center for Water Transportation Safety Key Laboratory of Marine Power Engineering&Technology(Ministry of Transport) Wuhan University of Technology

It is of a vital importance to reduce the frictional losses in marine diesel engines. Advanced surface textures have provided an e ective solution to friction performance of rubbing pairs due to the rapid development of surface engineering techniques. However,the mechanisms through which textured patterns and texturing methods prove beneficial remains unclear. To address this issue,the tribological system of the cylinder liner?piston ring(CLPR) is investigated in this work. Two types of surface textures(Micro concave,Micro V?groove) are processed on the cylinder specimen using di erent processing methods. Comparative study on the friction coe cients,worn surface texture features and oil film characteristics are performed. The results demonstrate that the processing method of surface texture a ect the performance of the CLPR pairs under the specific testing conditions. In addition the micro V?groove processed by CNCPM is more favorable for improving the wear performances at the low load,while the micro?con?cave processed by CE is more favorable for improving the wear performances at the high load. These findings are in helping to understand the e ect of surface texture on wear performance of CLPR.

关键词： Cylinder liner?piston ring(CLPR) Surface texture structure Frictional and wear characteristic Oil film characteristic

Magnetic emission intensity enhancement for amorphous alloys by constructing a multi-phase structure withα-Fe nanocrystals

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Nano Research 2024年第7期17卷 6630-6637页

作者： Ke Liu zhi qin Jie Shen zhi cheng Shiyue You Liang Ma Jing Zhou Wen Chen State Key Laboratory of Advanced Technology for Materials Synthesis and Processing School of Materials Science and EngineeringWuhan University of TechnologyWuhan 430070China Sanya Science and Education Innovation Park Wuhan University of TechnologySanya 572024China Hubei Longzhong Laboratory Wuhan University of Technology Xiangyang Demonstration ZoneXiangyang 441000China

The perturbation in the magnetic field generated by the rotation or oscillation of magnetic domains in magnetic materials can emit low-frequency electromagnetic waves,which are expected to be used in low-frequency ***,the magnetic emission intensity,defined by the perturbation ability,of current commercially applied amorphous alloys,such as Metglas,cannot meet the application requirements for low-frequency antennas due to the domain motion energy ***,a multi-phase Metglas amorphous alloy was constructed by incorporatingα-Fe nanocrystals using rapid annealing to manipulate the domain *** was found that 3.89 times higher magnetic emission intensity is obtained compared to the pristine due to the synergism of the deformation and displacement ***,the low-frequency magnetic emission performance verification was carried out by preparing magnetoelectric composites as the antenna vibrator by assembling the alloy and macro piezoelectric fiber composites(MFC).Enhancements of magnetic emission intensity are found at 93.3%and 49.2%at the first and second harmonic frequencies compared with the unmodified alloy ***,the approach leads to the development of high-performance communication with a novel standard for evaluation.

关键词： multi-phase amorphous alloys magnetic emission intensity enhancing mechanism magnetic domain pinning theory Jiles-Atherton model analysis

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基于网络虚拟展示的农机工业设计研究

农机化研究 2025年第3期47卷 186-191页

作者：尹程黄月芹覃祚萍柳州工学院广西柳州545616 柳州职业技术学院广西柳州545006

农业机械是促进农业发展,加快农业现代化进程的重要保障。随着农业生产模式的转变及社会的快速发展,农业机械的设计不再仅满足于以功能为导向的产品设计与制造,而是更加注重农户的使用体验。为此,以农业机械设计为研究对象,基于CMF对农... 详细信息

农业机械是促进农业发展,加快农业现代化进程的重要保障。随着农业生产模式的转变及社会的快速发展,农业机械的设计不再仅满足于以功能为导向的产品设计与制造,而是更加注重农户的使用体验。为此,以农业机械设计为研究对象,基于CMF对农业机械的外观及色彩要素进行分析,以提高农户使用体验感为主要研究目标对农业机械设计流程进行阐述,最终以虚拟仿真的形式将最终优化设计效果进行展示,形成完善的农业机械优化设计流程。研究结果可以为农业机械产品的设计提供技术指导与理论支撑。

关键词：虚拟仿真 CMF 设计展示

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Zwitterionic hyaluronic acid derivatives for co-delivery of both chemotherapeutic and nucleic acid drugs in breast cancer treatment

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Nano Research 2025年第1期18卷 607-617页

作者： Ruo-Lin Jiang Hui-Na Liu Yu-Fan Yang zhi-cheng Zhang Qi Dai Xiao-Yan Bao Lin-Jie Wu Ya-Xin qin Xin Tan Xiao-Yan Sun Xu-Fang Ying zhi-qing Ben Min Han Institute of Pharmaceutics College of Pharmaceutical SciencesZhejiang UniversityHangzhou 310058China Department of Radiation Oncology Key Laboratory of Cancer Prevention and InterventionThe Second Affiliated HospitalCollege of MedicineZhejiang UniversityHangzhou 310058China Hangzhou Institute of Innovative Medicine Zhejiang UniversityHangzhou 310058China Jinhua Institute of Zhejiang University Jinhua 321299China National Key Laboratory of Advanced Drug Delivery and Release Systems Zhejiang UniversityHangzhou 310058China Polytechnic institute Zhejiang UniversityHangzhou 310015China

Traditionally,hyaluronic acid has been widely used for drug delivery,but the current application bottleneck is that hyaluronic acid is hydrophilic and electronegative,which makes it difficult to carry hydrophobic drugs and small interfering RNA(siRNA)with the same *** on previous studies,we designed and synthesized hyaluronic acid nanocarriers HA-spermine/N,N,N-trimethylcystamine/DOX-TPP(HSTD)for loading siRNA to overcome the problem of siRNA release caused by strong electrostatic ***,N,N,Ntrimethylcystamine in the carrier can be degraded by intracellular glutathione to completely and rapidly release siRNA,thus promoting ***,when codelivered with the chemotherapy drug doxorubicin(DOX),this novel nanocarrier showed promising synergy in inhibiting tumor growth.

关键词： zwitterionic hyaluronic acid N N N-trimethylcystamine small interfering RNA(siRNA) doxorubicin

Molecular simulation study of the microstructures and properties of pyridinium ionic liquid[HPy][BF_(4)]mixed with acetonitrile

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原子与分子物理学报 2025年第4期42卷 27-32页

作者： XU Jian-Qiang MA Zhao-Peng cheng Si LIU zhi-Cong ZHU Guang-Lai Department of Physics School of Physics and Electronic InformationAnhui Normal UniversityWuhu 241002China

The microstructures and thermodynamic properties of mixed systems comprising pyridinium ionic liquid[HPy][BF_(4)]and acetonitrile at different mole fractions were studied using molecular dynamics simulation in this *** following properties were determined:density,self-diffusion coefficient,excess molar volume,and radial distribution *** results show that with an increase in the mole fraction of[HPy][BF_(4)],the self-diffusion coefficient ***,the excess molar volume initially decreases,reaches a minimum,and then *** rules of radial distribution functions(RDFs)of characteristic atoms are *** increasing the mole fraction of[HPy][BF_(4)],the first peak of the RDFs of HA1-F decreases,while that of CT6-CT6 rises at first and then *** indicates that the solvent molecules affect the polar and non-polar regions of[HPy][BF_(4)]differently.

关键词： Pyridinium ionic liquids Thermodynamic properties Molecular dynamics simulation Radial distribution functions

Parental Anxiety and Quality of Life of Epileptic Children

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Biomedical and Environmental Sciences 2008年第3期21卷 228-232页

作者： YONG LI cheng-YE JI JIONG qin zhi-XIANG ZHANG Institute of Child and Adolescent Health Peking University Health Science Center Department of Pediatrics Peking University First Hospital Beifing 100083 China

Objective To investigate the prevalence of parental anxiety associated with epileptic children, and to explore whether and how this specific condition affects children＇s quality of life （QOL）, and what are the significant determinants for parental anxiety. Methods Three hundred and forty parents whose children were affected with known epilepsy were enrolled in the study. Questionnaires for quality of life in childhood epilepsy （QOLCE）, and hospital anxiety and depression （HAD） of parents were used to collect demographic data of both children and their parents, as well as clinical manifestations of epilepsy and family status. Results Parental anxiety （of any severity） was observed in 191 subjects at interview, giving a prevalence rate of 56.2%. Of the 191 subjects, 18.5% reported mild anxiety, 24.4% moderate anxiety, and 13.2% severe anxiety. Factors associated with parental anxiety included frequency of seizure in children, average monthly income per person and parents＇ knowledge about epilepsy （P〈O.05）. Parental anxiety significantly （P--O.O00） correlated with quality of life of children with epilepsy. Conclusion Parents of children with epilepsy are at high risk of having anxiety. Factors associated with parental anxiety originate both from children and from parents. Parental anxiety is significantly related with children＇s QOL. It is important for experts concerned to recognize such a relationship to improve the QOL of children and their parents.

关键词： Anxiety Child Epilepsy Parents Quality of life

A case-based method of selecting covariates for digital soil mapping

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Journal of Integrative Agriculture 2020年第8期19卷 2127-2136页

作者： LIANG Peng qin cheng-zhi ZHU A-xing HOU zhi-wei FAN Nai-qing WANG Yi-jie State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application School of GeographyNanjing Normal UniversityNanjing 210097P.R.China Key Laboratory of Virtual Geographic Environment Ministry of EducationNanjing Normal UniversityNanjing 210023P.R.China Department of Geography University of Wisconsin-MadisonMadisonWI 53706USA

Selecting a proper set of covariates is one of the most important factors that influence the accuracy of digital soil mapping(DSM).The statistical or machine learning methods for selecting DSM covariates are not available for those situations with limited *** solve the problem,this paper proposed a case-based method which could formalize the covariate selection knowledge contained in practical DSM *** proposed method trained Random Forest(RF)classifiers with DSM cases extracted from the practical DSM applications and then used the trained classifiers to determine whether each one potential covariate should be used in a new DSM *** this study,we took topographic covariates as examples of covariates and extracted 191 DSM cases from 56 peer-reviewed journal articles to evaluate the performance of the proposed case-based method by Leave-One-Out cross *** with a novices’commonly-used way of selecting DSM covariates,the proposed case-based method improved more than 30%accuracy according to three quantitative evaluation indices(i.e.,recall,precision,and F1-score).The proposed method could be also applied to selecting the proper set of covariates for other similar geographical modeling domains,such as landslide susceptibility mapping,and species distribution modeling.

关键词： digital soil mapping covariates case-based reasoning Random Forest