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Evapotranspiration and humidity variations in response to land cover conversions in the Three Gorges Reservoir Region

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Journal of Mountain Science 2018年第3期15卷 590-605页

作者： DENG hua shao Jing-an Chongqing Youth Vocational & Technical College Chongqing 400712 China College of Geography and Tourism Chongqing Normal University Chongqing 401331 China Key Laboratory of Surface Process and Environment Remote Sensing in the Three Gorges Reservoir Area Chongqing 401331 China

A new land cover classification system was established for the Three Gorges Reservoir Region(TGRR) after considering the continuity of inundation and the natural characteristics of land cover. The potential evapotranspiration(PET) was predicted using a modified Penman-Monteith(P-M) model. The region's ratio of precipitation to evapotranspiration was calculated as the humidity index(HI). The data obtained was used to analyze climatic responses to land cover conversions from the perspectives of evapotranspiration and humidity variations. The results show that, from 1997 to 2009, the average annual PET increased in the early years and decreased later. In terms of overall spatial distribution, a significant reciprocal relationship appeared between annual PET and annual HI. In 1997,the annual PET was higher in the lower reaches than in the upper reaches of the TGRR, but the areas with high PET shifted substantially westward by 2003. The annual PET continued to increase in 2006, but the areas with high PET shrank by 2009. In contrast, the annual HI showed varying degrees of localized spatial variability. Over the three periods, the dominantforms of land cover conversions occurred from evergreen cover to seasonal green cover, from seasonal green cover to evergreen cover, and from seasonal green cover to seasonally inundated areas, respectively. These accounted for 48.0%, 38.4%, and 23.8% of the total areas of converted land covers in the three periods, respectively. During the period between 1997 and 2003, the main forms of land cover conversions resulted in both positive and negative growths in the average annual PET, while all of them pushed down the average annual HI. From 2003 to 2006, the reservoir region experienced neither a decrease in the annual PET nor an increase in the annual HI. The period between 2006 and 2009 saw a consistent downward trend in the annual PET and a consistent upward trend in the annual HI.

关键词： Land cover Evapotranspiration Humidity variations Response Three Gorges Reservoir Region

Single event upset rate modeling for ultra-deep submicron complementary metal-oxide-semiconductor devices

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Science China(Information Sciences) 2016年第4期59卷 56-66页

作者： Liang HE hua CHEN Peng SUN Xiaofei JIA Chongguang DAI Jing liu Long shao Zhaoqing liu School of Advanced Materials and Nanotechnology Xidian University School of Electronic and Information Engineering Ankang University

Based on the integral method of single event upset(SEU) rate and an improved charge collection model for ultra-deep submicron complementary metal-oxide-semiconductor(CMOS) devices, three methods of SEU rate calculation are verified and compared. The results show that the integral method and the figure of merit(FOM) methods are basically consistent at the ultra-deep submicron level. By proving the validity of the carrier collection model considering charge sharing, the applicability of two FOM methods is verified, and the trends of single-bit and multiple-bit upset rates for ultra-deep submicron CMOS are analyzed.

关键词： ultra-deep submicron complementary metal-oxide-semiconductor devices single event upset rates charge sharing

Polymerization Kinetics of Propylene with the MgCl_(2)-Supported Ziegler-Natta Catalysts——Active Centers with Different Tacticity and Fragmentation of the Catalyst

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Chinese Journal of Polymer Science 2021年第1期39卷 70-80,I0006页

作者： Wei-Ping Zheng Ya-Ping Ma Da-Lin Du Ai-hua He hua-Feng shao Chen-Guang liu Shandong Provincial Key Laboratory of Olefin Catalysis and Polymerization Key Laboratory of Rubber-Plastics(Ministry of Education)School of Polymer Science and EngineeringQingdao University of Science and TechnologyQingdao 266042China

The catalytic activity and stereospecificity of olefin polymerization by using heterogeneous TiCl_(4)/MgCl_(2) Ziegler-Natta(Z-N) catalysts are determined by the structure and nature of active centers, which are mysterious and fairly controversial. In this work, the propylene polymerization kinetics under different polymerization temperatures by using Z-N catalysts were investigated through monitoring the concentration of active centers [C*] with different tacticity. SEM was applied to characterize the catalyst morphologies and growing polypropylene(PP) particles. The lamellar thickness and crystallizability of PP obtained under different polymerization conditions were analyzed by DSC and SAXS. The PP fractions and active centers with different tacticity were obtained with solvent extraction fractionation method. The catalytic activity, active centers with different tacticity and propagation rate constant kp, fragmentation of the catalyst, crystalline structure of PP are correlated with temperature and time for propylene polymerizations. The polymerization temperature and time show complex influences on the propylene polymerization. The higher polymerization temperature(60 ℃) resulted higher activity, kp and lower [C*], and the isotactic active centers Ci* as the majority ones producing the highest isotactic polypropylene(iPP) components showed much higher kp when compared with the active centers with lower stereoselectivity. Appropriate polymerization time provided full fragmentation of the catalyst and minimum diffusion limitation. This work aims to elucidate the formation and evolution of active centers with different tacticity under different polymerization temperature and time and its relations with the fragmentation of the PP/catalyst particles, and provide the solutions to the improvement of catalyst activity and isotacticity of PP.

关键词： Polypropylene Catalytic activity Active center Catalyst fragmentation

Biocarbon with different microstructures derived from corn husks and their potassium storage properties

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Rare Metals 2021年第11期40卷 3166-3174页

作者： Meng Zhou Qing Wang Yuan Yuan shao-hua Luo Ya-Hui Zhang Xin liu School of Materials Science and Engineering Northeastern UniversityShenyang 110819China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China School of Resources and Materials Northeastern University at QinhuangdaoQinhuangdao 066004China Hebei Key Laboratory of Dielectric and Electrolyte Functional Material Qinhuangdao 066004China Qinhuangdao Key Laboratory of Advanced Energy Storage and Conversion Technology Qinhuangdao 066004China

In this paper,biocarbon was prepared from corn husks as anode materials for potassium ion batteries at temperatures ranging from 700 to 1600℃.The prepared biocarbon materials have amorphous phase structure and possess larger interlayer spacing than *** biocarbon exhibits enhanced graphitic degree and decreased amounts of surface defects,while the carbonization temperature gradually *** obtained potassium ion battery electrode at 1300℃ acquired high reversible capacity up to 216.6 mAh·g^(-1) at 0.1 A·g^(-1) after 100 cycles, and retained 128.6 mAh·g^(-1) at 1 A·g^(-1) even after500 *** results indicate that the samples prepared at 1300℃ have better electrochemical performance than other samples prepared at different temperatures,which was attributed to the decisive influence of microstructure on surface-induced and intercalating potassium storage.

关键词： Biocarbon Potassium ion battery Carbonization Capacitance Electrochemical performance

Eigen elastic mechanics and its variation principle

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中国有色金属学会会刊：英文版 2001年第2期11卷 281-282页

作者： GUO shao-hua 郭少华 College of Resources Environment and Civil Engineering Central South University

The fundamental equations and the corresponding boundary condition of elastic mechanics under mechanical representation are given by using the conception of eigen space and elastic variation principle. It is proved theoretically that the solution of anisotropic elastic mechanics consists of modal ones, which are obtained respectively from the modal equation of the different subspaces. A simple application is also given.

关键词： anisotropy eigen elastic mechanics variation principle modal equation

MicroRNA-324-3p Plays A Protective Role Against Coxsackievirus B3-Induced Viral Myocarditis

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Virologica Sinica 2021年第6期36卷 1585-1599页

作者： Tingjun liu Jing Tong Chen shao Junyan Qu hua Wang Yi Shi Yajing Lin Yun liu Shihe shao Hongxing Shen School of Medicine College Jiangsu UniversityZhenjiang212013China Xuzhou Municipal Center for Disease Control and Prevention Xuzhou221006China Department of Cardiology Affiliated Hospital of Jiangsu UniversityZhenjiang212000China Center of Infectious Disease West China Hospital Sichuan UniversityChengdu610041China

Viral myocarditis(VM) is an inflammatory disease of the myocardium associated with heart failure, which is caused by common viral infections. A majority of the infections are initiated by coxsackievirus B3(CVB3). Micro RNAs(mi RNAs)have a major role in various biological processes, including gene expression, cell growth, proliferation, and apoptosis, as well as viral infection and antiviral immune responses. Although, mi RNAs have been found to regulate viral infections,their role in CVB3 infection remains poorly understood. In the previous study, mi RNA microarray results showed that mi R-324-3 p expression levels were significantly increased when cells and mice were infected with CVB3. It was also found that miR-324-3p downregulated TRIM27 and decreased CVB3 replication in vitro and in vivo. In vitro, analysis of downstream signaling of TRIM27 revealed that, miR-324-3p inhibited CVB3 infection, and reduced cytopathic effect and viral plaque formation by reducing the expression of TRIM27. In vivo, miR-324-3p decreased the expression of TRIM27,reduced cardiac viral replication and load, thereby strongly attenuating cardiac injury and inflammation. Taken together,this study suggests that miR-324-3p targets TRIM27 to inhibit CVB3 replication and viral load, thereby reducing the cardiac injury associated with VM.

关键词： Coxsackievirus B3(CVB3) Viral myocarditis(VM) miR-324-3p TRIM27

Effects of seedling age on the growth stage and yield formation of hydroponically grown long-mat rice seedlings

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Journal of Integrative Agriculture 2020年第7期19卷 1755-1767页

作者： LI Yu-xiang liu Yang WANG Yu-hui DING Yan-feng WANG shao-hua liu Zheng-hui LI Gang-hua Jiangsu Collaborative Innovation Center for Modern Crop Production/National Engineering and Technology Center for Information Agricultrue/Key Laboratory of Crop Physiology and Ecology in Souther China Nanjing Agricultural UniversityNanjing 210095P.R.China The Key Laboratory of Oasis Eco-Agriculture of Xinjiang Production Construction Group/Agricultural College Shihezi UniversityShihezi 832003P.R.China

Understanding the characteristics of rice productivity is of great importance for achieving high yield ***,such traits have not yet been studied for different ages of hydroponically grown long-mat rice seedlings(HLMS),which constitutes a new method of seedling *** experiments were conducted to evaluate the effects of seedling age on the growth stage,photosynthesis characteristics,dry matter production,and yield of HLMS.A conventional japonica rice cultivar(Wuyunjing 24)and an indica hybrid rice cultivar(6 Liangyou 9368)were used as test *** results showed that the whole phase was shortened by 13-15 days for young seedlings(13-day-old)compared with old seedlings(27-day-old),which occurred because the growth process accelerated with the transplantation of young *** seedling age increased,the dry matter weight of stems of individual plants and of the population increased at the transplanting stage but decreased at the maturity stage(MS).Compared with that of 27-day-old seedlings,the average ratio of panicle weight to total plant dry weight of 13-day-old seedlings during a 2-year period increased by 3.71%for Wuyunjing 24 and by 3.78%for 6 Liangyou 9368 at the ***,as seedling age increased,the leaf area index and photosynthetic potential decreased for both cultivars,and the photosynthetic rate markedly decreased at the heading stage(HS).With the exception of that of Wuyunjing 24 from the jointing stage to the HS in 2014,the crop growth rate was higher for young seedlings than for old *** yield significantly decreased with seedling age,but no significant difference was detected between the 13-and 20-day-old seedlings for either ***,equilibrious and high biological yield formation,vigorous growth in the late stages,and high photosynthetic production capacity are important characteristics and causes of the efficient and sustainable output of photosynthetic systems and for achieving high yield

关键词： rice(Oryza sativa L.) seedling age,growth stage yield photosynthetic matter production

Ensemble-based optimization of hydraulically fractured horizontal well placement in shale gas reservoir through Hough transform parameterization

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Petroleum Science 2021年第3期18卷 839-851页

作者： Liang Xue shao-hua Gu Xie-Er Jiang Yue-Tian liu Chen Yang State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing 102249China Department of Oil-Gas Field Development Engineering College of Petroleum EngineeringChina University of Petroleum(Beijing)Beijing 102249China State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Efective Development Beijing 100083China Sinopec Petroleum Exploration and Production Research Institute Beijing 100083China School of Water Conservancy North China University of Water Resources and Electric PowerZhengzhou 450046HenanChina

Shale gas reservoirs have been successfully developed due to the advancement of the horizontal well drilling and multistage hydraulic fracturing ***,the optimization design of the horizontal well drilling,hydraulic fracturing,and operational schedule is a challenging *** ensemble-based optimization method(EnOpt)is proposed here to optimize the design of the hydraulically fractured horizontal well in the shale gas *** objective is to maximize the net present value(NPV)which requires a simulation model to predict the cumulative shale gas *** accurately describe the geometry of the hydraulic fractures,the embedded discrete fracture modeling method(EDFM)is used to construct the shale gas simulation *** efects of gas absorption,Knudsen difusion,natural and hydraulic fractures,and gas-water two phase fow are considered in the shale gas production *** improve the parameter continuity and Gaussianity required by the EnOpt method,the Hough transformation parameterization is used to characterize the horizontal *** results show that the proposed method can efectively optimize the design parameters of the hydraulically fractured horizontal well,and the NPV can be improved greatly after optimization so that the design parameters can approach to their optimal values.

关键词： Shale gas Ensemble optimization Embedded discrete fracture model Hough transformation

妊娠晚期妇女膳食模式与营养相关疾病的关联性研究

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实用预防医学 2018年第4期25卷 388-394页

作者：韩少华刘茹辛贺圣文提慧慧王凡金笑笑潍坊医学院公共卫生与管理学院山东潍坊261053 潍坊医学院附属医院产科

目的了解潍坊市妊娠晚期妇女膳食模式与营养相关疾病的关系。方法对在潍坊市某三甲医院产检的350名妊娠晚期妇女进行问卷调查并收集相关信息,膳食调查部分采用半定量食物频率法,数据处理中采用因子分析归纳膳食模式,用logistic回归分析... 详细信息

目的了解潍坊市妊娠晚期妇女膳食模式与营养相关疾病的关系。方法对在潍坊市某三甲医院产检的350名妊娠晚期妇女进行问卷调查并收集相关信息,膳食调查部分采用半定量食物频率法,数据处理中采用因子分析归纳膳食模式,用logistic回归分析探寻膳食模式与相关疾病的关系。结果 (1)因子分析归纳出4种膳食模式:营养型、零食型、荤食型、素食型。(2)膳食模式相关分析:4种膳食模式除钙外,蛋白质、脂肪、碳水化合物、维生素A、维生素C、维生素D、铁等各类营养素每日摄入量均不同,差异有统计学意义(P<0.05)。单因素分析显示四型膳食模式孕妇的年龄(χ~2=19.852,P=0.019)、体重增长(χ~2=30.545,P=0.000)、知识得分(χ~2=17.603,P=0.001)、贫血(χ~2=15.465,P=0.001)、文化程度(χ~2=34.378,P=0.000)、职业(χ~2=34.915,P=0.003)、收入(χ~2=24.417,P=0.004)、下肢水肿(χ~2=10.295,P=0.016)、患病数量(χ~2=14.396,P=0.002)及血糖异常(χ~2=18.167,P=0.044)分布差异有统计学意义,对膳食模式进行多分类logistic回归分析显示零食型膳食模式与妊娠期糖耐量异常具有相关性(OR=4.986,95%CI:1.274~19.525),荤食型膳食模式与患妊娠期超重和下肢水肿具有相关性(OR1=4.707,95%CI:1.084~20.441;OR2=2.690,95%CI:1.061~6.816),素食型膳食模式与患妊娠期贫血和妊娠期患病数量具有相关性(OR1=0.443,95%CI:0.254~0.772;OR2=1.919,95%CI:1.076~3.420)。(3)膳食模式与营养相关疾病分析:二分类logistic回归分析显示,膳食模式与贫血(OR=2.576,95%CI:1.540~4.309)、妊娠期超重(OR=6.220,95%CI:2.399~16.127)及妊娠期高血压(OR=20.656,95%CI:1.192~357.867)、糖耐量异常(OR=4.587,95%CI:1.092~19.261)均具有相关性。结论膳食模式与妊娠晚期相关疾病如妊娠期贫血、体重增长超标、妊娠期高血压和糖耐量异常的形成密切相关;孕期不合理的营养摄入可以导致相关疾病的发生,应加强健康教育,加强孕期营养监督和指导,改善母婴健康,从而为早期营养干预提供科学依据。

关键词：妊娠晚期膳食模式营养相关疾病