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Environmental behaviors of selenium in soil of typical selenosis area,China

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Journal of Environmental Sciences 2008年第7期20卷 859-864页

作者： LI Yonghua wang wuyi LUO Kunli Institute of Geographical Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China

Daba Mountain area is one of the two endemic selenosis areas in China,which may relate with the environmental behaviors of selenium (Se) in *** study focuses on the concentraion and distribution of Se and its relationships with some other elements in natural soil in the *** average concentration of Se in Daba Mountain soils was 14.3 times higher than the value cited for natural soil background worldwide,suggesting that soils in the region were contaminated by the *** finding was confirmed...

关键词： selenium (Se) selenosis area geoaccumulation index soil profile

Low-Frequency Reciprocating Fretting Wear Testing System Design and Experiment Research

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Journal of Harbin Institute of Technology(New Series) 2015年第4期22卷 62-65页

作者： Zhongnan wang wuyi wang Guangyu Zhang School of Mechatronics Engineering Harbin Institute of Technology

The fretting wear is resulted from different or same sample's surfaces by the small variationand leads to mechanism failures. The main factors consist of the variation of normal load and oscillation frequencies,among which surface topography of different materials are the main factors to the problems of the fretting ***,a novel low-frequency reciprocating fretting wear test system is designed upon the principle of Friction coefficient measurement. Four metal and non-metallic samples are measured under various normal load and oscillation frequencies to obtain the instantaneous friction coefficient in the repeat experiments. In fact,the experimental results show that Co F curves of different samples with the increase of the normal load are the similar exponential decay or parabolic shapes,which are consistent with the literatures to verify the rational design and reliable-operation of the system under the conditions of different frequencies.

关键词： fretting wear measuring-head reciprocating platform coefficient of friction oscillation frequency

Spatio-temporal measures of electrophysiological correlates for behavioral multisensory enhancement during visual,auditory and somatosensory stimulation:A behavioral and ERP study

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Neuroscience Bulletin 2013年第6期29卷 715-724页

作者： wuyi wang Li Hu Hongyan Cui Xiaobo Xie Yong Hu School of Precision Instruments and Opto-Electronics Engineering Tianjin University Institute of Biomedical Engineering Chinese Academy of Medical Science and Peking Union Medical College Key Laboratory of Cognition and Personality (Ministry of Education) and School of Psychology Southwest University Department of Orthopaedics and Traumatology the University of Hong Kong

Multisensory enhancement,as a facilitation phenomenon,is responsible for superior behavioral performance when an individual is responding to cross-modal versus modality-specific ***,the event-related potential（ERP） counterparts of behavioral multisensory enhancement are not well *** recorded ERPs and behavioral data from 14 healthy volunteers with three types of target stimuli（modality-specific,bimodal,and trimodal） to examine the spatio-temporal electrophysiological characteristics of multisensory enhancement by comparing behavioral data with *** found a strong correlation between P3 latency and behavioral performance in terms of reaction time（RT）（R = 0.98,P ＆lt;0.001）,suggesting that P3 latency constitutes a temporal measure of behavioral multisensory *** addition,a fast RT and short P3 latency were found when comparing the modality-specific visual target with the modality-specific auditory and somatosensory *** results indicate that behavioral multisensory enhancement can be identified by the latency and source distribution of the P3 *** findings may advance our understanding of the neuronal mechanisms of multisensory enhancement.

关键词： multisensory enhancement temporal measure P3 latency visual dominance

北上台风“杜苏芮”登陆后河北中南部的雨滴谱特征分析

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气候与环境研究 2024年第4期29卷 497-506页

作者：黄兆楚董晓波王梧熠李禧亮闫非侯劭禹张丹中国气象局雄安大气边界层重点开放实验室河北雄安新区071800 河北省气象与生态环境重点实验室石家庄050021 河北省人工影响天气中心石家庄050021 中国气象局邢台大气环境野外科学试验基地河北邢台054000 石家庄市气象局石家庄050081

利用雨滴谱仪观测资料,分析了2023年7月29日至8月1日的河北中南部极端降水的雨滴谱特征,研究降水的微物理特征变化。结果表明,降雨强度R小于50 mm/h时,雨滴直径随着R的增加明显增大,R超过50 mm/h时,随着R的继续增大,雨滴的质量加权平均... 详细信息

利用雨滴谱仪观测资料,分析了2023年7月29日至8月1日的河北中南部极端降水的雨滴谱特征,研究降水的微物理特征变化。结果表明,降雨强度R小于50 mm/h时,雨滴直径随着R的增加明显增大,R超过50 mm/h时,随着R的继续增大,雨滴的质量加权平均直径不再继续增长,趋于平衡,稳定在2 mm。此次降水位于海洋性对流特征区域的点较多,而位于大陆性的点较少,仍有很多点位于两种形态的过渡区间内,表明地面降水的微物理过程具有显著的时空变化。利用K-means聚类算法,将降水样本按照滴谱特征分为5类,发现不同强度滴谱特征具有明显差异,当降水强度高于50 mm/h时,降水的滴谱性质体现为较大的加权平均直径和较大的粒子数浓度,正是因为有持续稳定的大直径粒子和高数浓度的特征,雨滴谱的突变加上台风输送源源不断的水汽,才能在短时间内产生强降水。利用滴谱数据进行雷达降水估测关系拟合,得到雷达反射率Z、差分反射率KDP和R的拟合公式Z=224R1.44和R=45.8KDP0.77,使用R-KDP定量降水估测关系,结果要优于使用Z-R关系,尤其是超过40 mm/h的降水,估计误差明显好于使用Z-R关系。

关键词：特大暴雨雨滴谱微物理特征 Z-R关系

Influence of high-fluorine environmental background on crops and human health in hot spring-type fluorosis-diseased areas

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Chinese Journal Of Geochemistry 2008年第4期27卷 335-341页

作者： LAN De WU Daishe LI Ping wang Tengsheng CHEN Chengguang wang wuyi Key Lab of Poyang Lake Ecology and Bio-resource Utilization Ministry of Education College of Environmental Science and Engineering Nanchang University Nanchang 330031 China Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China The Health Center of Wenquan Town Yuexi 246630 China

Drinking water-type fluorosis is the most harmful endemic disease in China with the largest number of sufferers. Although the implementation of the policy to alter water sources to lower fluoride level has effectively controlled the spread of this kind of endemic disease,its prevalence could not thoroughly be stopped because the high-fluoride environmental background in these endemically diseased areas could still do harm to human health through food chain. Therefore,it is necessary to conduct a more deep-going study on the drinking water-type fluoro-sis. To investigate the effect of high fluorine environmental background on crops and human health in the hot spring-type fluorosis-diseased areas,local water,paddy soil,rice,whole vegetables and soils around their roots were sampled for analysis. The results were compared with those of the control groups in fluorosis-free areas which are similar to the fluorosis-diseased areas both in natural background and in social background. It is indicated that rice and vegetables can accumulate water-soluble fluorine either in soils or in irrigating water,and different crops have different abilities of fixing fluorine. The contents of fluorine in different parts of vegetables in the fluorosis-diseased and fluorosis-free areas were statistically categorized. The results showed that the fluorine contents of roots,tubers,leaves and flowers of vegetables in the fluorosis-diseased areas are 3.56,1.17,3.07 and 3.23 mg/kg,respectively. However,comparisons showed that in the fluorosis-free areas,the fluorine contents are 2.17,0.70,1.91 and 2.52 mg/kg,respectively. Moreover,different parts of a crop also show significantly different fluorine fixation abilities. It is demonstrated that the fluorine contents of the strongly metabolic parts are relatively high. For example,the fluo-rine contents of roots,leaves and flowers of vegetables are much higher than those of stems. The fluorine fixation ability of seeds is very weak. In order to redu

关键词：含氟水土壤氟中毒地下水

Relationship between selenium concentration in child hair and the distribution of Kashin-Beck Disease in Tibet, China

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Frontiers of Medicine 2007年第2期1卷 223-225页

作者： LI Shunjiang YANG Linsheng wang wuyi LI Yonghua LI Hairong XIRAO Ruodeng Environmental School Beijing Normal UniversityBeijing 100875China Institute of Geographical Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China Tibet Municipality Centers for Disease Control and Prevention Lhasa 850000China

The focus of this study is to determine the relationship between selenium(Se)concentrations in child hair and the distribution of Kashin-Beck disease(KBD)in *** hair of children in typical KBD-affected areas and non-disease areas was collected,and its Se concentrations were measured by atomic fluorescent *** Se concentrations in child hair were(0.13±0.04)and(0.18±0.07)μg/g respectively in KBD areas and non-disease areas respectively,which are significantly *** areas supplemented with Se in Tibet,the Se concentration of hair in KBD-affected areas was higher than that in non-diseased areas,being(0.28±0.03)and(0.18±0.04)μg/g *** is a close relationship between the Se concentrations in hair and KBD *** supplement increase the Se concentrations in the human *** Se supplementation is important to prevent KBD in Tibet.

关键词： Kashin-Beck disease Tibet selenium human hair

Negative Haloes and Geochemical Field Systems of Hydrothermal Deposits

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Acta Geologica Sinica(English Edition) 1993年第2期67卷 195-209页

作者： Ji Kejian, wang Liben, Lu Fengxiang, wang wuyi and Zhang Jianhua Institute of Mineral Deposits, Chinese Academy of Geological Sciences, Beijing Institute of Mineral Deposits Chinese Academy of Geological Sciences Beijing

Primary haloes of hydrothermal deposits were previously considered as positive haloes. Although it has been recently suggested that primary haloes incude positive and negative ones, almost all the research work on primary haloes has still focused on positive haloes for various reasons. In order to understand the source of ore substances a number of large hydrothermal deposits related to magmatism including porphyry, skarn and vein type deposits have been studied. It has been found that negative haloes exist on the peripheries of positive haloes of a mineral deposit. On the basis of the study the authors propose the concept of the geochemical field system of ore-forming elements of hydrotherreal deposits, i. e., with the orebody as the centre outwards there occur the mineralized field, positive halo field, depleted field and background field successively.

关键词： hydrothermal deposit negative halo geochemical field system

Random Terpolymer of Carbon Dioxide,Butadiene and Epoxides:Synthesis,Functionalization and Degradability

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Chinese Journal of Chemistry 2024年第14期42卷 1630-1636页

作者： Zi wang wuyi Zheng Sicong Yue Kaihao Chen Jun Ling Xufeng Ni MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhouZhejiang310058 China Westlake Electronics Group Co. Ltd.HangzhouZhejiang310012 China

The utilization of carbon dioxide(CO_(2))as a C1 feedstock is consistently attractive,especially in the preparation of sustainable polymeric *** this contribution,a terpolymer of CO_(2),1,3-butadiene(BD)and epoxide is synthesized by scandium triflate catalyzed cationic ring-opening copolymerization ofα-ethylidene-δ-vinyl-δ-valerolactone(EVL),an intermediate derived from CO_(2)and BD,with *** obtained terpolymer with a CO_(2)content of 22 mol%has a number-average molecular weight(M_(n))up to 7.8 kg/mol and a dispersity(Đ)of *** reactivity ratios of EVL and cyclohexene oxide(CHO)are determined as 0.01 and 1.07,respectively,suggesting random characteristic of the *** preserved C=C double bonds from BD allow for the further modification of the terpolymer by photoinitiated *** yielded networks are fluorescent and *** method offers enhanced versatility to the synthesis and additional functionalization of CO_(2)-based polymers.

关键词： Ring-opening polymerization Copolymerization Carbon dioxide Butadiene Scandium triflate Fluorescence

FACTORS CONTROLLING DIFFERENTIATION OF SELENIUM ECONVIRONMENT IN THE LOESS PLATEAU

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Journal of Geographical Sciences 1994年第Z1期4卷 138-145页

作者： Qu Cuihui wang wuyi(Institute of Geography, CAS, Beijing 100101People’s Republic of China)

Low selenium (Se) belt in the Loess Plateau constitutes anessential part of low Se belt in China. Se backgound of loess is only46.5 ug/kg. Centre of low Se content in soil surface is situated in thecentral-north of the Loess Plateau, While Se background of soilsurface in southwest is higher because of less precipitation, and thatin southeast is higher too owing to finer soil texture. Both of themare divided into low and normal Se eco-environment by precipitationof 450 mm, a transition from subhumid to semiarid *** of mobile elements in drinking water are negativelycorrelated wtth precipitatioll. The same happens in soils except *** Se content in soils with closed conditions is negntivelycorrelated with precipitation as well. These susaest thatprecipitation plays a key role in differentiating Se eco-environmentother than the centre of low Se content in soil surface.

关键词： selenium element migration,eco-environment Loess Plateau