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Response of Stream Pollution Characteristics to Catchment Land Cover in Cao-E River Basin, China

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Pedosphere 2011年第1期21卷 115-123页

作者： SHEN Ye-Na lue jun CHEN Ding-Jiang SHI Yi-Ming Department of Natural Resources College of Environmental Science and Natural Resources Zhejiang University Hangzhou 310029 (China) China Ministry of Education Key Lab of Environmental Remediation and Ecological Health Zhejiang University Hangzhou 310029 (China) Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition Zhejiang University Hangzhou 310029 (China)

This study addressed the relationship of river water pollution characteristics to land covers and human activities in the catchments in a complete river system named Cao-E River in eastern *** on the hydrogeochemical data collected monthly over a period of 3 years,cluster analysis(CA) and principal component analysis(PCA) were adopted to categorize the river reaches and reveal their pollution *** to the differences of water quality in the river reaches and land use patterns and average population densities in their catchments,the whole river system could be categorized into three groups of river reaches,i.e.,non-point sources pollution reaches(NPSPR),urban reaches(UR) and mixed sources pollution reaches(MSPR).In UR and MSPR,the water quality was mainly impacted by nutrient and organic pollution,while in NPSPR nutrient pollution was the main *** nitrate was the main nitrogen form in NPSPR and particulate phosphorus was the main phosphorus form in *** were no apparent trends for the variations of pollutant concentrations with increasing river flows in NPSPR and MSPR,while in UR the pollutant concentrations decreased with increasing river *** dry season was the critical period for water pollution control in ***,catchment land covers and human activities had significant impact on river reach water pollution type,nutrient forms and water quality responses to hydrological conditions,which might be crucial for developing strategies to combat water pollution in watershed scale.

关键词： cluster analysis hydrological conditions pollution factors principle component analysis water quality

INFlueNCE OF VOCl2-ADDITIVE IN Rh CATALYST ON CO HYDROGENATION

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Journal of Energy Chemistry 1995年第1期 52-58页

作者： ZHOU Jian-lue LI jun CHEN Yao-QiangGONG Mao-Chu CHEN YuDepartment, of Chemistry caul Analytical & Testing Center Sichuan University Chengdu, Sichuan 610061

The influence of VOCl2 additive in the supported Rh catalysts derived from both Rh2 (CO )4 Cl2 and RhCl3 on CO hydrogenation was investigated. The VOCl2 additive as a promoter can effectively enhance the CO conversion and catalytic selectivity to ethanol. This effect is caused by the interaction of Rh with vanadium promoter. It is found that the Rh centers on which the gem- adsorbed CO could be formed are main active sites. The Rh2(CO)4Cl2 complex is better than the RhCl3 salt as the precursor of the Rh catalyst for the CO hydrogenation to ethanol.

关键词： CO hydrogenation ethanol Rh catalyst vanadium promoter

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基于单片机的鱼用投饵机自动控制系统

农机化研究 2006年第2期28卷 166-168页

作者：李君略俞龙王卫星刘华广东农业机械研究所广州510630 华南农业大学工程学院广州510642

目前在淡水养鱼业的生产中,使用的投饵机控制系统存在着定时不准确、可靠性差、投饵与间歇时间设置不合理、不能调节投饵距离、浪费饵料等问题。为了解决此类问题,研制了基于单片机的鱼用投饵机自动控制系统,该系统设定参数为供饵时间... 详细信息

目前在淡水养鱼业的生产中,使用的投饵机控制系统存在着定时不准确、可靠性差、投饵与间歇时间设置不合理、不能调节投饵距离、浪费饵料等问题。为了解决此类问题,研制了基于单片机的鱼用投饵机自动控制系统,该系统设定参数为供饵时间、停饵时间、投饵时间和投饵距离,控制对象为输送减速交流电机和投饵直流电机;同时,从硬件和软件方面介绍了本自动控制系统的设计和制作。试验结果表明,该系统能够控制鱼用投饵机进行定时、定量投饵,做到科学喂鱼。

关键词：水养殖学鱼用投饵机设计自动控制单片机

锌指蛋白260基因 rs34550124多态性与缺血性脑卒中痰证、血瘀证显著关联

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中国老年学杂志 2023年第12期43卷 2827-2833页

作者：古联唐略钧陈卓陈杏梅赵心怡黄先利苏莉广西中医药大学第一附属医院广西南宁530023 广西中医药大学广西医科大学公共卫生学院

目的探讨锌指蛋白(ZNF)260 rs34550124多态性与缺血性脑卒中痰证、血瘀证及临床生化指标的相关性。方法采用病例-对照研究。采用实时荧光定量聚合酶链反应(qRT-PCR)实验技术来测定外周血ZNF260基因的mRNA表达水平,并采用MassARRAYSNP基... 详细信息

目的探讨锌指蛋白(ZNF)260 rs34550124多态性与缺血性脑卒中痰证、血瘀证及临床生化指标的相关性。方法采用病例-对照研究。采用实时荧光定量聚合酶链反应(qRT-PCR)实验技术来测定外周血ZNF260基因的mRNA表达水平,并采用MassARRAYSNP基因分型实验技术对其进行基因分型。采用“研究对象相关信息采集调查表”结合医院信息系统收集血糖、凝血、血压等临床资料。采用Hardy Weinberg遗传平衡检验方法评估样本代表性。采用非条件Logistic回归模型分析各遗传模型(加性模型、显性模型、隐性模型)与疾病的关联;采用一般线性回归分析多态性位点与相关数量性状的关联。结果ZNF260基因rs34550124多态性与缺血性脑卒中痰证[显性模型:OR=0.73,95%CI(0.56~0.95),P=0.022;校正年龄、性别后,OR=0.73,95%CI(0.56~0.95),P=0.021]、痰证和血瘀证发生风险显著相关[显性模型:OR=0.72,95%CI(0.57~0.92),P=0.009;校正年龄、性别后,OR=0.72,95%CI(0.57~0.92),P=0.009]。ZNF260基因rs34550124多态性与缺血性脑卒中患者的收缩压(SBP)、餐后2 h血糖(2 h PG)、凝血标志物[国际标准化比率(INR)、血小板(PLT)、凝血酶原时间(PT)、凝血酶原时间活动度(PTA)]水平显著相关(P<0.05)。结论ZNF260基因rs34550124多态性可能影响缺血性脑卒中痰证及血瘀证发生过程,且ZNF260基因rs34550124多态性可能影响缺血性脑卒中患者的血压、血糖及凝血功能。

关键词：缺血性脑卒中锌指蛋白260基因单核苷酸多态性痰证血瘀证

Mechanical Properties and Microstructure of Si_(3)N_(4)-TiC Nanocomposites

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Journal of Materials Science & Technology 2005年第6期21卷 899-902页

作者： Zhijie lue Xing AI jun ZHAO School of Mechanical and Electronic Engineering Shandong University of Architecture and Engineering Jinan 250014 China School of Mechanical Engineering Shandong University Jinan 250061 China

Si3N4/TiC nanocomposite ceramics have been fabricated by hot pressing technique with Al2O3 and Y2O3 as additives. The results showed that well dispersed composite powder was carried out by adding dispersant and adjusting pH values of suspensions. Remarkable increase in flexural strength at room temperatures was obtained by adding nanoparticles in Si3N4 matrix with 10% （wt pct） of nano-Si3N4 and 15% of nano-TiC. The flexural strength, fracture toughness and hardness were 1025 MPa, 7.5 MPa.m^1/2 and 15.6 GPa, respectively. The microstructures of materials were analyzed by scanning electron microscopy （SEM） and transmission electron microscopy （TEM）, which indicated that TiC nanoparticles distribute in the matrix and at the grain boundaries. According to the fracture form, low contents of nano particles could refine matrix grains and lead to the crack deflection as well as crack pinning. The multiplex microstructure was formed by mixing nano-Si3N4 particles. The crack trajectories exhibited crack deflection, rod-like grain bridging and pull-out.

关键词： Si3N4/TiC Nanocomposite Mechanical properties Microstructure

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联合收割机监测系统研究现状及展望

现代农业装备 2005年第12期26卷 46-48页

作者：李君略俞龙刘华周汉林广东省农业机械研究所华南农业大学工程学院

概述了国内外联合收割机监测系统的研究现状,提出CAN总线与嵌入式技术的有机结合是联合收割机实现作业过程综合监测的有效途径。

关键词：联合收割机 CAN总线嵌入式系统

VR content creation and exploration with deep learning: A survey

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Computational Visual Media 2020年第1期6卷 3-28页

作者： Miao Wang Xu-Quan Lyu Yi-jun Li Fang-lue Zhang State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijing 100191China. Peng Cheng Laboratory Shenzhen 518000China School of Engineering and Computer Science Victoria University of WellingtonNew Zealand

Virtual reality(VR)offers an artificial,computer generated simulation of a real life *** originated in the 1960 s and has evolved to provide increasing immersion,interactivity,imagination,and *** deep learning systems are able to represent and compose information at various levels in a deep hierarchical fashion,they can build very powerful models which leverage large quantities of visual media *** of VR methods and applications has been significantly boosted by the recent developments in deep learning *** content creation and exploration relates to image and video analysis,synthesis and editing,so deep learning methods such as fully convolutional networks and general adversarial networks are widely employed,designed specifically to handle panoramic images and video and virtual 3 D *** article surveys recent research that uses such deep learning methods for VR content creation and *** considers the problems involved,and discusses possible future directions in this active and emerging research area.

关键词： virtual reality deep learning neural networks 360°image and video virtual content

A mild and efficient method for nucleophilic aromatic fluorination using tetrabutylammonium fluoride as fluorinating reagent

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Chinese Chemical Letters 2010年第2期21卷 151-154页

作者： Hu, Yu Feng Luo, jun lue, Chun Xu Nanjing Univ Sci & Technol Sch Chem Engn Nanjing 210094 Peoples R China

Anhydrous tetrabutylammonium fluoride(TBAF_(anh).) has been found to be a highly efficient fluorinating reagent for nucleophilic aromatic fluorinations such as fluorodenitration or halogen exchange(Halex) *** products were formed in high to excellent yields under surprisingly mild reaction conditions and no phenol or ether side-products were detected in these reactions.

关键词： TBAF_(anh). Fluoroaromatics Fluorodenitration Halex

A Study on Radiative Dileptonic Decays B^0（Bs）→γe^＋e^-

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Communications in Theoretical Physics 2007年第2期47卷 299-302页

作者： CHEN jun-Xiao HOU Zhao-Yu lue Cai-Dian Institute of High Energy Physics the Chinese Academy of Sciences P.O. Box 918（4） Beijing 100049 China College of Physical Science and Information Engineering Hebei Normal University Shijiazhuang 050016 China Mathematics and Physics Department Shijiazhuang Railway Institute Shijiazhuang 050043 China

We study the rare radiative dileptonlc decays B^0（Bs）→γe^＋e^- （e = e, μ） in the standard model By using the B meson wave function constrained by non-leptonic decays, the branching ratios turn out to be of the order of 10^-9 for Bs→γe^＋e^-, γe^＋e^-, and 10^-10 for Bs→γe^＋e^-, γe^＋e^-. Based on the study, these decays are accessible at the near future LHC-b experiment, which are useful to determine the B（B,） wave function.

关键词： radiative decay B meson wave function