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Elevated Ducts and Low Clouds over the Central Western Pacific Ocean in Winter Based on GPS Soundings and Satellite Observation

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Journal of Ocean University of China 2021年第2期20卷 244-256页

作者： LI Xiaodong SHENG Lifang wang wencai College of Oceanic and Atmospheric Sciences Ocean University of ChinaQingdao 266100China Key Laboratory of Physical Oceanography Ocean University of ChinaQingdao 266100China

Both low clouds and elevated ducts are common phenomena in the oceanic atmosphere. Low clouds affect elevated ducts by changing the structure of atmospheric temperature and humidity. However, due to the limitation of met-ocean measurements, research on them is still scattered. This paper presents the distribution of elevated ducts and clouds over the central Western Pacific Ocean(WPO) based on Global Position System(GPS) sounding data and Himawari-8 satellite products from November 2015 to January 2016. Results show that the frequency of elevated ducts detected by ship-based GPS soundings was as high as 77% over the central WPO. The height and frequency of elevated ducts are closely related to the low clouds. If there are no clouds, the occurrence probability and mean base height of the elevated ducts are 14% and 730 m, respectively. By comparison, the occurrence probability and mean base height increase up to 24% and 1471 m, respectively, in the presence of cumulus(Cu) clouds, and 22% and 1511 m, respectively, in the presence of stratocumulus(Sc) clouds. Elevated ducts occur near the cloud top. The analysis of geopotential height and wind fields from the European Centre for Medium-Range Weather Forecasts(ECMWF) reanalysis dataset(ERA-interim) shows that the study area is covered by a strong and stable subtropical high, and slowly sinking dry air masses inside the subtropical high are above the moist boundary-layer air mass. The appearance and evolution of low clouds will adjust the temperature and humidity structure of the lower troposphere. If there are no clouds, the marine boundary layer(MBL) is the classic mixed boundary layer. Humidity gradient and subsidence inversion are formed atop the mixed layer. When low clouds are present, long wave radiation and entrainment atop clouds form a strong temperature inversion and humidity gradient, which strengthen elevated ducts. However, when Sc clouds are decoupled, a weaker temperature inversion and humidity gradient ma

关键词： elevated duct cumulus cloud stratocumulus cloud marine boundary layer subtropical high

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The occurrences and geochemical characteristics of thorium in iron ore in the Bayan Obo deposit, Northern China

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Acta Geochimica 2020年第1期39卷 139-154页

作者： Xiaozhi Hou Zhanfeng Yang Zhenjiang wang wencai wang Mining Research Institute Inner Mongolia University of Science and TechnologyBaotou 014010China Rare Earth Research and the Comprehensive Utilization State Key Laboratory of Bayan Obo Baotou 014000China Baotou Rare Earth Research Institute Baotou 014000China

The Bayan Obo deposit in northern China is an ultra-large Fe–REE–Nb *** occurrences,and geochemical characteristics of thorium in iron ores from the Bayan Obo Main Ore Body were examined using chemical analysis,field emission scanning electron microscopy,energy dispersive spectrometer,and automatic mineral analysis *** identified that 91.69%of ThO2 in the combined samples was mainly distributed in rare earth minerals(bastnaesite,huanghoite,monazite;56.43%abundance in the samples),iron minerals(magnetite,hematite,pyrite;20.97%),niobium minerals(aeschynite;14.29%),and gangue minerals(aegirine,riebeckite,mica,dolomite,apatite,fluorite;4.22%).An unidentified portion(4.09%)of ThO2 may occur in other niobium minerals(niobite,ilmenorutile,pyrochlore).Only a few independent minerals of thorium occur in the iron ore *** mainly occurs in rare earth minerals in the form of isomorphic *** of the geochemical characteristics of the major elements indicate that thorium mineralization in the Main Ore Body was related to alkali metasomatism,which provided source material and favorable porosity for hydrothermal *** elements such as Sc,Nb,Zr,and Ta have higher correlation coefficients with thorium,which resulted from being related to the relevant minerals formed during thorium *** addition,correlation analysis of ThO2 and TFe,and REO and TFe in the six types of iron ore samples showed that ThO2 did not always account for the highest distribution rate in rare earth minerals,and the main occurrence minerals of ThO2 were closely related to iron ore types.

关键词： Thorium Occurrence state Distribution law Geochemical characteristics Iron ore Bayan Obo deposit

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Hormesis-like growth and photosynthetic physiology of marine diatom Phaeodactylum tricornutum Bohlin exposed to polystyrene microplastics

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Frontiers of Environmental Science & Engineering 2022年第1期16卷 51-63页

作者： Zuyin Chen Lihua Li Lichong Hao Yu Hong wencai wang College of Environmental Science and Engineering Beijing Forestry UniversityBeijing 100083China College of Materials Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China

The effects of pristine polystyrene microplastics(pMPs)without any pretreatment at different concentrations(0,10,20,50,and 100 mg/L)on Phaeodactylum tricornutum Bohlin at two initial algae densities(105 and 106 cells/mL)were assessed in this ***-like effects were found when microalgae grew with *** results showed that pMPs inhibited microalgae growth under a high concentration of microplastics tolerated by individual algal cell(low initial algae density)(up to-80.189.71%)but promoted growth when the situation was opposite(up to 15.273.66%).The contents of photosynthetic pigments including chlorophyll a,chlorophyll c and carotenoids showed resistance to pMPs stress under a low initial algae density and increased with time,but the opposite was true under a high initial algae *** with the low initial algae density group,Qp received less inhibition,and NPQ(heat dissipation)also decreased under the high initial algae *** the low initial algae density,OJIP parameters such as Sm,N,Area,Pi Abs,ѱo,φEo,TRo/RC and ETo/RC were more perturbed initially and returned to the levels of the control group(without pMPs)over time,but they remained stable throughout the experiment at high initial algae *** results show that microplastics in the marine environment may have different toxic effects on *** at different growth stages,which is of great significance for understanding the impact of microplastics on marine microalgae and aquatic ecosystems.

关键词： Microplastics Marine microalgae Phaeodactylum tricornutum Bohlin Growth Photosynthetic pigments Chlorophyll fluorescence parameters

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Synthesis and evaluation of bio-based elastomer based on diethyl itaconate for oil-resistance applications

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Science China Chemistry 2016年第11期59卷 1376-1383页

作者： Weiwei Lei He Qiao Xinxin Zhou wencai wang Liqun Zhang Runguo wang Kuo-Chih Hua State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical Technology Key Laboratory of Beijing City for Preparation and Processing of Novel Polymer Materials Beijing University of Chemical Technology Engineering Center of Ministry of Education on Elastomer Materials Energy Saving and Resource Utilization Beijing University of Chemical Technology Goodyear Innovation Center Goodyear Tire & Rubber Co.

Bio-based elastomer poly(diethyl itaconate-co-isoprene)(PDEII) was designed and synthesized by redox-initiated emulsion polymerization from diethyl itaconate and isoprene with mass ratio of 20:80, 40:60, 60:40 and 80:20. The number-average molecular weights of PDEII exceeded 140000 with relatively high yields. The physical properties of PDEII, such as glass transition temperatures and thermostability, were comparable with conventional synthetic elastomers and can be readily tuned by varying the ratio of diethyl itaconate to isoprene. The interaction between silica and PDEII macromolecules was effectively enhanced with the increase of diethyl itaconate content by endowing high polarity. The oil-resistance relevant properties of silica/PDEII80(80% diethyl itaconate, 20% isoprene) such as retention of tensile strength, retention of elongation at break and change in volume even surpass those of silica/NBR 240 S after soaked in ASTM 3# oil at different temperatures.

关键词： bio-based elastomer synthesis oil-resistance

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Natural rubber/nitrile butadiene rubber/hindered phenol composites with high-damping properties

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International Journal of Smart and Nano Materials 2015年第4期6卷 239-250页

作者： Xiuying Zhao Jingna Yang Detao Zhao Yonglai Lu wencai wang Liqun Zhang Toshio Nishi Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials Beijing University of Chemical TechnologyBeijing 100029P.R.China Beijing Engineering Research Center of Advanced Elastomers Beijing University of Chemical TechnologyBeijing 100029P.R.China Department of Organic and Polymeric Materials Graduate School of Science and EngineeringTokyo Institute of Technology2-12-1 O-okayamaMeguro-kuTokyo 152-8552Japan

New natural rubber(NR)/nitrile butadiene rubber(NBR)/hindered phenol(AO-80)composites with high-damping properties were prepared in this *** morpholo-gical,structural,and mechanical properties were characterized by atomic force micro-scopy(AFM),polarized Fourier transform infrared spectrometer(FTIR),dynamic mechanical thermal analyzer(DMTA),and a tensile *** composite consisted of two phases:the NR phase and the NBR/AO-80 *** was partial compat-ibility between the NR phase and the NBR/AO-80 phase,and the NR/NBR/AO-80(50/50/20)composite exhibited a co-continuous ***-induced crystal-lization occurred in the NR phase at strains higher than 200%,and strain-induced orientation appeared in the NBR/AO-80 phase with the increase of strain from 100%to 500%.The composites had a special stress–strain behavior and mechanical properties because of the simultaneous strain-induced orientation and strain-induced *** the working temperature range of a seismic isolation bearing,the composites(especially the NR/NBR/AO-80(50/50/20)composite)presented a high loss factor,high area of loss peak(TA),and high hysteresis ***,the NR/NBR/AO-80 rubber composites are expected to have important application as a high-perfor-mance damping material for rubber bearing.

关键词： natural rubber nitrile butadiene rubber damping properties strain-induced orientation rubber bearing

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Wind-induced hydrodynamic changes impact on sediment resuspension for large, shallow Lake Taihu, China

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International Journal of Sediment Research 2019年第3期34卷 205-215页

作者： Abdul Jalil Yiping Li Ke Zhang Xiaomeng Gao wencai wang Hafiz Osama Sarwar Khan Baozhu Pan Salar Ali Kumud Acharya State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes Ministry of Education Hohai University College of Environment Hohai University Laboratory Base of Eco-hydraulic Engineering in Arid Area Xi'an University of Technology Key Laboratory of Watershed Geographic Sciences Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Division of Hydrologic Sciences Desert Research Institute

The internal sediment release is a key factor controlling eutrophication processes in large, shallow *** resuspension is associated with the wave and current induced shear stress in large, shallow lakes. The current study investigated the wind field impacts on sediment resuspension from the bottom at Meiliang Bay of large, shallow Lake Taihu. The impacts of the wind field on the wave, current, and wave-current combined shear stresses were calculated. The critical wind speed range was 4–6 m/s after which wave and current shear stress started to increase abruptly, and onshore wind directions were found to be mainly responsible for greater shear stress at the bottom of Lake Taihu. A second order polynomial fitting correlation was found between wave(R20.4756) and current(R20.4466) shear stresses with wind speed. Wave shear stress accounted for 92.5% of the total shear stress at Meiliang *** critical wave shear stress and critical total shear stress were 0.13 N/m2 for sediment resuspension whereas the current shear stress was 0.019 N/m~2 after which suspended sediment concentrations(SSC)increased abruptly. A second order polynomial fitting correlation was found between wave(R20.739),current(R20.6264), and total shear stress(R20.7394) with SSC concentrations at Meiliang Bay of Lake Taihu. The sediment resuspension rate was 120 to 738 g/m~2/d during 4–6 m/s onshore winds while offshore winds contributed Z 200 g/m~2/d. The study results reveal the driving mechanism for understanding the role of the wind field in sediment resuspension while considering wind speed and direction as control parameters to define wave and current shear stresses.

关键词： Shear stress Sediment resuspension Lake Taihu Hydrodynamics Wind field

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SHORT-RANGE ORDER STRUCTURES OF Fe-Ge AMORPHOUS THIN FILMS

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Acta Metallurgica Sinica(English Letters) 1989年第10期2卷 255-260页

作者： wang wencai CHEN Yu Peking University,Beijing,China Associate Professor,Dept.of Physics,Peking University Beijing,China

The short-range order structures of Fe_xGe_(1-x) amorphous thin films,(x=8.7,19.1 and 28.5%)have been studied by means of X-ray absorption *** nearest neighbors around a Ge or an Fe atom are constituted by two coordinate sub-shells with a very short dis- tance,In two films with lower Fe content,structural parameters of the nearest neighbors around a Ge atom are very near to that in amorphous germanium,and the positions of Fe at- oms are randomly *** when x=28.5%,some great changes occur on the short-range order structure of a-Fe_xGe_(1-x) film:its structure deviates from continuous ran- dora network and tends toward dense random packing of ***,there is a strong- er interaction between near neighboring Fe-Ge atoms in a-Fe_xGe_(1-x) films.

关键词： Fe-Ge amorphous thin film X-ray short-range order structure X-ray absorption spectra

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Fe-Ge非晶薄膜的短程序结构

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金属学报 1989年第1期25卷 B031-B036页

作者：王文采陈玉北京大学物理系北京大学

用X射线K吸收谱方法研究了Fe_xGe_(1-x)(x=8.7,19.1和28.5%)非晶薄膜的短程序结构。三种合金中,Ge或Fe原子的最近邻结构组态均由Ge,Fe分别形成的两个间距很小的双配位层构成。Fe含量较低的前两种合金,Ge的最近邻结构参数与非晶Ge非常相... 详细信息

用X射线K吸收谱方法研究了Fe_xGe_(1-x)(x=8.7,19.1和28.5%)非晶薄膜的短程序结构。三种合金中,Ge或Fe原子的最近邻结构组态均由Ge,Fe分别形成的两个间距很小的双配位层构成。Fe含量较低的前两种合金,Ge的最近邻结构参数与非晶Ge非常相近,Fe作为Ge的最近邻原子接近于无规的代位式配位。当Fe含量达到28.5at.-%时,相应的非晶薄膜的短程序发生了很大的变化;非晶已偏离连续无规网络结构,显示出朝无规密堆结构变化的趋向。同时,还显示出在该合金中Fe-Ge原子间存在较强的相互作用。

关键词： Fe-Ge 非晶薄膜程序结构 X线

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鄂尔多斯市农地资源调查及效益评价

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中国农业资源与区划 2021年第5期42卷 70-76页

作者：王文才内蒙古鄂尔多斯市土地调查规划院

[目的]文章分析了2007—2016年10年来鄂尔多斯市农地数量变化情况,同时从经济、社会、生态3个维度入手,对此期间内鄂尔多斯市农地资源利用效益进行测度。[方法]建立鄂尔多斯市农地利用效益指标体系,采用极差法、熵值法确定指标权重,进... 详细信息

[目的]文章分析了2007—2016年10年来鄂尔多斯市农地数量变化情况,同时从经济、社会、生态3个维度入手,对此期间内鄂尔多斯市农地资源利用效益进行测度。[方法]建立鄂尔多斯市农地利用效益指标体系,采用极差法、熵值法确定指标权重,进而对经济效益、社会效益、生态效益及综合效益进行测算。[结果]鄂尔多斯市农地主要包括耕地、园地、林地和牧草地4种类型,占比分别为2.97%、16.23%、43.81%和31.86%;2007—2016年鄂尔多斯市农地数量逐年上升,以园地增长面积最大,耕地增长面积最小,形成以草地、园地为主,林地、耕地为辅的分布特征;10年来鄂尔多斯市经济效益、社会效益、生态效益呈上升趋势,经济效益、社会效益上升幅度大于生态效益,且经济效益、社会效益优于生态效益;除社会效益外,鄂尔多斯市农地利用综合效益、经济效益、生态效益于2012年皆处于"低谷期",但综合效益整体处于上升态势,4种效益上升斜率逐渐趋于一致,农地利用效益步入稳定上升阶段。[结论]鄂尔多斯市农地利用效率逐渐趋于协调稳定上升状态。

关键词：农地鄂尔多斯市经济社会生态效益

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四川毛茛属五新种和一新变种,其中一新种代表一新组

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广西植物 2022年第1期42卷 1-9页

作者：王文采中国科学院植物研究所系统与进化植物学国家重点实验室北京100093

该文描述了自四川西部发现的毛茛科毛茛属五新种。其中:三新种,即石棉毛茛(Ranunculus shimianensis)、细叉叶毛茛(***)和细裂叶毛茛(***)隶属于美丽毛茛组(***);第四新种,即泸定毛茛(***)隶属于毛茛组(***);第五新种,即丝茎毛茛(***)... 详细信息

该文描述了自四川西部发现的毛茛科毛茛属五新种。其中:三新种,即石棉毛茛(Ranunculus shimianensis)、细叉叶毛茛(***)和细裂叶毛茛(***)隶属于美丽毛茛组(***);第四新种,即泸定毛茛(***)隶属于毛茛组(***);第五新种,即丝茎毛茛(***)代表一新组,特征为植株平卧,匍匐茎十或十多条辐射状开展,花的花瓣3片,雄蕊2枚。此外,还描述了叉裂叶云生毛茛(*** ***)一新变种。

关键词：毛茛科毛茛属新种新变种四川

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