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410篇 您的检索式:作者名="LI WenBo"
    题名 作者 年代 出处 被引量
1Rice DENSE AND ERECT PANICLE 2 is essential for determining panicle outgrowth and elongation显示文摘包括谷物尺寸和圆锥花序形态学,圆锥花序的建筑学直接决定谷物产量。圆锥花序直立,为在中国的北部分完成理想的植物建筑学被选择,引起了米饭 breeders 的增加的注意。这里,稠密、直立的圆锥花序 2 (dep2 ) 异种,显示出稠密、直立的圆锥花序显型,被识别。没有任何已知的功能的领域, DEP2 编码植物特定的蛋白质。表示介绍 DEP2 表明它高度在年轻纸巾被表示,与在年轻圆锥花序的大多数丰富。词法并且表示分析显示在 DEP2 的那个变化主要影响脊柱和主要、第二等的分支的快速的延伸,但是不损害圆锥花序 primordia 的开始或形成。进一步的分析建议在 dep2 的圆锥花序长度的减少被一个缺点在圆锥花序的指数的延伸期间在房间增长引起。尽管有在 dep2 异种的一种更紧缩的植物类型,在谷物生产的重要改变都没在野类型和 dep2 异种之间被发现。因此, DEP2 的学习不仅加强我们圆锥花序建筑学的分子的基因基础的理解而且为米饭繁殖有重要含意。Feng Li Wenbo Liu Jiuyou Tang Jinfeng Chen Hongning Tong Bin Hu Chunlai Li Jun Fang Mingsheng Chen Chengcai Chu 2010Cell Research2010,20,7:51
2Mapping wetland changes in China between 1978 and 2008显示文摘Four wetland maps for all China have been produced,based on Landsat and CBERS-02B remote sensing data between 1978 and 2008 (1978,1990,2000 and 2008).These maps were mainly developed by manual interpretation and validated by substantial field investigation in 2009.Based on these maps,we analyzed the 2008 wetland distribution in China and discussed wetland changes and their drivers over the past 30 years.(i) There were about 324097 km 2 of wetlands in 2008,for which inland marshes or swamps were the most common wetland type (35%),with lakes (26%) second.Most of the wetlands were in Heilongjiang,Inner Mongolia,Qinghai and Tibet,occupying about 55% of the national wetland area.(ii) From 1978 to 2008,China's wetland area continually and significantly decreased,by about 33% based on changes in the wetland map.This was in sharp contrast to the increase in artificial wetlands,which increased by about 122%.Inland marshes accounted for the main loss of total wetlands from 1978 to 2000.From 2000 through 2008,riverine and lacustrine wetlands constituted the main wetland loss.Fortunately however,the rate of wetland loss decreased from 5523 to 831 km 2 /a.(iii) The change ratio of lost natural wetlands (including inland and coastal wetlands) to non-wetlands has decreased slightly over the past 30 years.From 1978 to 1990,nearly all natural wetlands (98%) lost were transformed into non-wetlands.However,the ratio declined to 86% from 1990 to 2000,and to 77% from 2000 to 2008.(iv) All Chinese provinces were divided into three groups according to patterns of wetland changes,which could relate to the driving forces of such changes.Tibet was completely different from other provinces,as it was one representative example in which there was a net wetland increase,because of global warming and decreased human activity since 1990.Increased economic development caused considerable wetland loss in most eastern provinces,and artificial wetlands increased.NIU ZhenGuo ZHANG HaiYing WANG XianWei YAO WenBo ZHOU DeMin ZHAO KuiYi ZHAO Hui LI NaNa HUANG HuaBing LI CongCong YANG Jun LIU CaiXia LIU Shuang WANG Lin LI Zhan YANG ZhenZhong QIAO Fei ZHENG YaoMin CHEN YanLei SHENG YongWei GAO XiaoHong ZHU WeiHong WANG WenQing WANG Hong WENG YongLing ZHUANG DaFang LIU JiYuan LUO ZhiCai CHENG Xiao GUO ZiQi GONG Peng 2012Chinese Science Bulletin2012,57,22:51
3REE and C-O Isotopic Geochemistry of Calcites from the World-class Huize Pb-Zn Deposits,Yunnan,China:Implications for the Ore Genesis显示文摘在西南的中国,云南省的世界级的 Huize Pb-Zn 存款在 Sichuan-Yunnan-Guizhou Pb-Zn polymetallic metallogenic 省的中心定位了,在 Pb+Zn 等级有超过500万吨的 Pb+Zn 储备比25%高并且包含丰富的联系金属例如 Ag , Ge , Cd ,并且 Ga 。存款在更低的含碳的碳酸盐阶层和在 orefield 的北、西南的部分散布了的二叠的 Emeishan 暗岩被招待。方解石是在沉积物的主要矿石的唯一的脉石矿物质并且能被分类进三种类型,也就是笨重,根据他们的出现的补丁和静脉方解石。在方解石和矿石矿物质之间并且在方解石的三种类型之中有没设置的接触,显示他们是有不同阶段的一样的形成矿石的年龄,它的形成的顺序从对到静脉方解石的补丁笨重。HUANG Zhilong LI Xiaobiao ZHOU Meifu LI Wenbo JIN Zhongguo 2010Acta Geologica Sinica(English Edition)2010,84,3:42
4The First Imported Case of Monkeypox in the Mainland of China—Chongqing Municipality,China,September 16,2022显示文摘Monkeypox is a zoonotic viral disease caused by the monkeypox virus(MPXV),and historically,all outbreaks have been linked to Africa;however,monkeypox has been posing an alarming challenge to the world in 2022(1)as approximately 60,000 cases have been reported in more than 100 nations and regions worldwide(2).Currently,many cases of monkeypox were identified in many nonendemic countries outside of Central and West Africa,and human-to-human transmission has occurred frequently,especially among men who have sex with men(MSM)presenting new clinical symptoms similar to syphilis and other sexually transmitted infections(3).Hua Zhao Wenling Wang Li Zhao Sheng Ye Jingdong Song Roujian Lu Hua Zong Changcheng Wu Wei Huang Baoying Huang Yao Deng Ruhan A Wujuan Xie Li Qi Wenbo Xu Hua Ling Wenjie Tan 2022China CDC weekly2022,4,38:35
5SHRIMP U-Pb dating for a K-bentonite bed in the Tieling Formation,North China显示文摘A SHRIMP U-Pb zircon age of 1437±21 Ma was obtained for a recently discovered K-bentonite bed in the Tieling Formation,situated northeast of Beijing at the boundary between Liaoning and Hebei provinces,on the northern margin of the North China Craton(NCC).The SHRIMP U-Pb age places Tieling Formation near the end of the Calymmian Period of the early Mesoproterozoic Era.In addition,a SHRIMP U-Pb zircon date of 1372±18 Ma was acquired for K-bentonite beds in the overlying,dark-shale-dominated Xiamaling Formation from the same location northeast of Beijing.This date assigns a similar Mid-Mesoproterozoic(Ectasian Period) age for the Xiamaling Formation,as have previously determined dates from other sections northwest of Beijing.These dates indicate that the Tieling and Xiamaling formations,as well as the related succession in the eastern part of the Yanshan Mountains,represented by the well-known Meso-to Neoproterozoic standard section in Jixian,can be correlated well with sections northwest of Beijing in the western part of the Yanshan Mountains.In other words,the boundary between the Calymmian and Ectasian periods in the northern parts of the NCC is marked by the unconformity between the Tieling and Xiamaling formations in the northern NCC.This boundary was previously ascribed to the 'Qinyu Orogeny' and thought to be of Grenville age.In this regard,the conventional 'Qinyu Orogeny' should now be regarded as a short-lived regional uplift during Early Mesoproterozoic time,rather than a result from the Grenvillian assembly of the NCC to the Rodinia Supercontinent(~1.0 Ga).SU WenBo LI HuaiKun HUFF W D ETTENSOHN F R ZHANG ShiHong ZHOU HongYing WAN YuSheng 2010Chinese Science Bulletin2010,55,29:30
6Effect of Cultivation on Spatial Distribution of Nematode Trophic Groups in Black Soil显示文摘Geostatistics combined with GIS was applied to assess the spatial distribution of nematode trophic groups following two contrasting soil uses in the black soil region of Northeast China. Two plots, one with fallow for 12 years and the other cultivated, were marked on regular square grids with 2-m spacing. Soil samples were collected from each sampling point, nematodes were extracted from these samples and classified into four trophic groups: bacterivores, fungivores, plant parasites, and omnivores/predators. The numbers of total nematodes and trophic groups analyzed had normal distributions on both fallow and cultivated plots. The absolute abundances of total nematodes and trophic groups were observed to be much more homogeneous on cultivated plot than on fallow one. Geostatistical analysis showed that the densities of total nematodes and trophic groups on both fallow and cultivated plots exhibited spatial dependence at the sampled scale and their experimental semivariograms were adjusted to a spherical or exponential model, except those of bacterivores and fungivores on cultivated plot. The spatial distribution of nematode trophic groups was found to be different for the two land uses, indicating that cultivation changed the native condition for soil nematode activities.LIANG WENJU, LI QI, JIANG YONG, CHEN WENBO and WEN DAZHONGShenyang Experimental Station of Ecology, Institute of Applied Ecology, the Chinese Academy of Sciences, Shenyang 110016 (China) 2003Pedosphere2003,13,2:29
7Rb-Sr isotopic dating of sphalerite from the giant Huize Zn-Pb ore field, Yunnan Province, Southwestern China显示文摘The giant Huize Zn-Pb ore field in Yunnan Province, southwestern China, comprises the Qilinchang and Kuangshanchang deposits. The deposits are large in scale (more than 5 Mt of Zn and Pb) and high in grade (average grade of total Zn and Pb is 30%). Reported in this paper are the results of Rb-Sr isotopic dating of sphalerite from this ore field. Two precise ages (223.5±3.9 Ma and 226±6.4 Ma) have been obtained from two isochrons. These two ages are close to the reported ages of native copper mineralizations related to the Emeishan flood basalts in this region, which are 226 Ma to 228 Ma. Previous studies showed that the magnitude of uplift resultant from the Emeishan flood basalts is greater than 1000 m, indicating that the Kuangshanchang and Qilinchang deposits were formed during the same geological event and originated by fluid migration during uplifting resultant from the Emeishan flood basalts.LI Wenbo 2009Chinese Journal Of Geochemistry2009,28,1:25
8Sr-Nd isotope geochemistry of eolian dust of the arid-semiarid areas in China: Implications for loess provenance and monsoon evolution显示文摘Minerals and rocks have distinct 87Sr/86Sr and 143Nd/144Nd ratios, depending on their geological origin and ages, and these isotope ratios are less altered than elemental composition during transport in the atmosphere or after deposition as sediments, thus stable isotopes of Sr and Nd have great potential as tracers for provenance and trans- port of materials. During the hypergene process, Sr isotope ratios of sediments are controlled by their parent rocks, particle sizes and chemical weathering. In general, the higher the Sr isotope ratios of parent rocks, and/or the more the fine-grained fractions, and/or the stronger the chemical weathering, thus the higher the Sr isotope ratios of sediments. On the contrary, there are lower Sr isotope ratios of sedi- ments. Nd isotope ratios of sediments, independent of their particle sizes and chemical weathering, are only associated with parent rocks. For the prove- nance of the Chinese Loess Plateau, different re- seachers drew discordant and even contradictory conclusions by using the method of Sr-Nd isotopic tracing. From the previous Nd isotope data, it is con- sidered that the Tarim Basin, deserts in the central and west parts of Inner Mongolia and the Tibetan Plateau are the main sources of the Chinese Loess Plateau, and are also manufacturers for eolian dust of the Far East regions, together with the Chinese Loess Plateau. Sr isotope ratios of eolian dust are solely affected by wind sorting and weather- ing-pedogenesis due to its homogeneous composi- tion in the Chinese Loess Plateau. Wind sorting isrelated to the East Asian winter monsoon but weath- ering-pedogenesis is mainly associated with the East Asian summer monsoon. Studies on Sr isotopic compositions of the loess-paleosol sequence suggest that 87Sr/86Sr ratios in acid-soluble materials are an index for chemical weathering intensity of the Chi- nese Loess Plateau, indicating the East Asian sum- mer monsoon variations, whereas 87Sr/86Sr ratios in acid-insoluble materials are significantly controlled by particle sizes, and can be used as a proxy indicator reflecting the East Asian winter monsoon variations. Variations of 87Sr/86Sr ratios in acid-insoluble materi- als in the past 2.6Ma further demonstrate that the East Asian winter monsoon gradually strengthened since the beginning of the Quaternary period. This result agrees with the prior conclusion that climate gradually cooled since the onset of the Quaternary Ice Age.RAO Wenbo YANG Jiedong CHEN Jun LI Gaojun 2006Chinese Science Bulletin2006,51,12:21
9A review on thermal conductivity of magnesium and its alloys显示文摘This review summarizes recent researching works the thermal conductivity of Mg–Zn,Mg–Al,Mg–Mn and Mg–RE alloys.Solute atoms,heat treatment,deformation and temperature,which have significant influence on the thermal conductivity of magnesium alloys,are highlighted.For an individual solute atom,its effects on thermal conductivity are highly dependent on its chemical valence,radius and extra-nuclear electrons.The thermal conductivity of Mg alloys is decreased by solution treatment,but improved by aging and/or annealing treatments.As for the deformed Mg alloys,the thermal conductivity along transverse or normal direction is superior to that of along extrusion or rolling direction.We expect this review is helpful for those who are working on developing Mg alloys with superior thermal conductivity.©2020 Published by Elsevier B.V.on behalf of Chongqing University.Shubo Li Xinyu Yang Jiangtao Hou Wenbo Du 2020Journal of Magnesium and Alloys2020,8,1:18
10Efficacy of open reduction and internal fixation with a miniplate and hollow screw in the treatment of Lisfranc injury显示文摘Baoliang Li Wenbo Zhao Lei Liu Fuguo Huang Guanglin Wang Yue Fang 2015Chinese Journal of Traumatology2015,18,1:17
11High-speed and high-efficiency three-dimensional shape measurement based on Gray-coded light显示文摘Fringe projection profilometry has been increasingly sought and applied in dynamic three dimensional(3D)shape measurement.In this work,a robust,high-efficiency 3D measurement based on Gray-coded light is proposed.Unlike the traditional method,a tripartite phase unwrapping method is proposed to avoid the jump errors on the boundary of code words,which are mainly caused by the defocusing of the projector and the motion of the tested object.Subsequently,the time overlapping coding strategy is presented to greatly increase the coding ef-ficiency,decreasing the projected number in each group from seven(i.e.,3+4)to four(i.e.,3+1)for one restored 3D frame.The combination of two proposed techniques allows the reconstruction of a pixel-wise and unambiguous 3D geometry of dynamic scenes with strong noise using every four projected patterns.To the best of our knowledge,the presented techniques for the first time preserve the high anti-noise ability of a method based on the Gray code while overcoming the drawbacks of jump errors and low coding efficiency.Experiments have demonstrated that the proposed method can achieve robust,high efficiency 3D shape measurement of high speed dynamic scenes even polluted by strong noise.ZHOUJIE WU WENBO GUO YUEYANG LI YIHANG LIU QICAN ZHANG 2020Photonics Research2020,8,6:17
12COVID-19 Outbreak Caused by Contaminated Packaging of Imported Cold-Chain Products—Liaoning Province,China,July 2020显示文摘Summary What is known about this topic?Few major outbreaks of coronavirus disease 2019(COVID-19)have occurred in China after major nonpharmaceutical interventions and vaccines have been deployed and implemented.However,sporadic outbreaks that had high possibility to be linked to cold chain products were reported in several cities of China..What is added by this report?In July 2020,a COVID-19 outbreak occurred in Dalian,China.The investigations of this outbreak strongly suggested that the infection source was from COVID-19 virus-contaminated packaging of frozen seafood during inbound unloading personnel contact.What are the implications for public health practice?Virus contaminated paper surfaces could maintain infectivity for at least 17–24 days at-25℃.Exposure to COVID-19 virus-contaminated surfaces is a potential route for introducing the virus to a susceptible population.Countries with no domestic transmission of COVID-19 should consider introducing prevention strategies for both inbound travellers and imported goods.Several measures to prevent the introduction of the virus via cold-chain goods can be implemented.Huilai Ma1 Jianqun Zhang Ji Wang Ying Qin Cao Chen Yang Song Liang Wang Jun Meng Lingling Mao Fengqin Li Ning Li Jian Cai Yong Zhang Dayan Wang Yunting Xia Hong Wang Shaofeng Jiang Xiang Zhao Peihua Niu Wenjie Tan Tao Ma Yecheng Yao Naiying Mao Zhen Zhu Tianjiao Ji Qian Yang Baoying Huang Li Zhao Jianxing Yu Li Bai Shuangli Zhu Dongyan Wang Yan Zhang Yingwei Sun Mingchun Luan Yanhai Wang Haibo Sun Shihong Yang Zhijian Bo Xiang Ren Zhongjie Li George Fu Gao Wei Yao Wenqing Yao Zijian Feng Wenbo Xu 2021China CDC weekly2021,3,21:16
13REE Geochemistry of Sulfides from the Huize Zn-Pb Ore Field, Yunnan Province: Implication for the Sources of Ore-forming Metals显示文摘在来自 Huize Zn-Pb 矿石域的硫化物的 REE 丰富在 preconcentration 以后与 ICPMS 被决定。在 26 件硫化物样品(包括的黄铁矿,方铅矿和闪锌矿) 的 REE 丰富是很低的,与从 1.6 x 10 ~的Σ R EE (-9) 到 166.8 x 10 ^(-9) 。他们的 LREE/HREE 比率从 7.6 ~ 98 ,相对显示出 LREE 丰富。δ E u 价值低于 1,显示他们从一个弄空 Eu 、减少的液体系统被扔。Similarto 招待矿石的碳酸盐阶层,方解石把填横切阶层也显示出的碳酸盐的破裂或差错的细叶脉与碳酸盐分开清楚的 Eu 弄空。这显示碳酸盐细叶脉和他们的父母液体可能从阶层被采购并且继承了阶层的 REE geochemical 特征。因此,硫化物和方解石的 REE-geochemical 特征,从一个形成矿石的热水的系统被扔,类似于碳酸盐阶层的那些,并且强烈建议矿石金属主要从碳酸盐阶层被采购。LI Wenbo HUANG Zhilong QI Liang 2007Acta Geologica Sinica(English Edition)2007,81,3:15
14Respiratory Virus Multiplex RT-PCR Assay Sensitivities and Influence Factors in Hospitalized Children with Lower Respiratory Tract Infections显示文摘Multiplex RT-PCR assays have been widely used tools for detection and differentiation of a panel of respiratory viral pathogens. In this study, we evaluated the Qiagen ResPlex II V2.0 kit and explored factors influencing its sensitivity. Nasopharyngeal swab (NPS) specimens were prospectively collected from pediatric inpatients with lower respiratory tract infections at the time of admission in the Shenzhen Children's Hospital from May 2009 to April 2010. Total nucleic acids were extracted using the EZ1 system (Qiagen, Germany) and 17 respiratory viruses and genotypes including influenza A virus (FluA), FluB, parainfluenza virus 1 (PIV1), PIV2, PIV3, PIV4, respiratory syncytial virus (RSV), human metapneumovirus (hMPV), rhinoviruses (RhV), enteroviruses (EnV), human bocaviruses (hBoV), adenoviruses (AdV), four coronaviruses (229E, OC43, NL63 and HKU1), and FluA 2009 pandemic H1N1(H1N1-p) were detected and identified by the ResPlex II kit. In parallel, 16 real-time TaqMan quantitative RT-PCR assays were used to quantitatively detect each virus except for RhV. Influenza and parainfluenza viral cultures were also performed. Among the total 438 NPS specimens collected during the study period, one or more viral pathogens were detected in 274 (62.6%) and 201(45.9%) specimens by monoplex TaqMan RT-PCR and multiplex ResPlex, respectively. When results from monoplex PCR or cell culture were used as the reference standard, the multiplex PCR possessed specificities of 92.9-100.0%. The sensitivity of multiplex PCR for PIV3, hMPV, PIV1 and BoV were 73.1%, 70%, 66.7% and 55.6%, respectively, while low sensitivities (11.1%-40.0%) were observed for FluA, EnV, OC43, RSV and H1N1. Among the seven viruses/genotypes detected with higher frequencies, multiplex PCR sensitivities were correlated significantly with viral loads determined by the TaqMan RT-PCR in FluA, H1N1-p and RSV (p=0.011-0.000). The Qiagen ResPlex II multiplex RT-PCR kit possesses excellent specificity for simultaneous detection of 17 viral pathogens in NPS specimens in pediatric inpatients at the time of admission. The sensitivity of multiplex RT-PCR was influenced by viral loads, specimen process methods, primer and probe design and amplification condition.Jikui Deng Zhuoya Ma Wenbo Huang Chengrong Li Heping Wang Yuejie Zheng Rong Zhou Yi-Wei Tang 2013Virologica Sinica2013,28,2:14
15Eleven COVID-19 Outbreaks with Local Transmissions Caused by the Imported SARS-CoV-2 Delta VOC-China,July-August,2021显示文摘Starting from December 2019,Wuhan,China,encountered the first outbreak of coronavirus disease 2019(COVID-19)(1-2).The epidemic was successfully suppressed by strict containment so that the number of infected people was reduced to 0 on April 8,2020(3–4).After that,China experienced roughly 3 dozen outbreaks with local transmission caused by imported severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).Lei Zhou Kai Nie Hongting Zhao Xiang Zhao Bixiong Ye Ji Wang Cao Chen Hong Wang Jiangli Di Jinsong Li Chao Li Zhixiao Chen Ruiqi Ren Peihua Niu Hui Chen Tao Chen Yali Wang Lili Li Bingxue Han Ruhan A Si Chen Dan Li Dan Li Chunxia Jin Xin Zhang Jiangmei Liu Chunyu Xu Yecheng Yao Yenan Feng Zhili Li Bike Zhang Yang Song Peter Hao Yanping Zhang Hao Li Qun Li George F.Gao Guoqing Shi Wenbo Xu 2021China CDC weekly2021,3,41:13
16Icosahedral quasicrystalline phase in an as-cast Mg-Zn-Er alloy显示文摘The microstructure of an as-cast Mg-Zn-Er alloy was investigated through scanning electron microscopy (SEM) and transmission electron microscopy (TEM) equipped with energy dispersive spectroscopy (EDS). The results indicate that two different second phases, one with eutectoid-lamellar morphology and the other with granular shape, distribute in the α-Mg matrix. The coexistence of the face-centered icosahedral quasicrystalline phase (I-phase) and W-phase with the face-centered cubic structure is found in the as-cast alloy. The coexistence of I-phase and W-phase in the Mg-Zn-Er alloy is because the W-phase is the primary phase and the I-phase forms by peritectic reaction during solidification.LI Jianhui DU Wenbo LI Shubo WANG Zhaohui 2009Rare Metals2009,28,3:13
17Spatial variations of terrain and their impacts on landscape patterns in the transition zone from mountains to plains—A case study of Qihe River Basin in the Taihang Mountains显示文摘Terrain plays a key role in landscape pattern formation, particularly in the transition zones from mountains to plains.Exploring the relationships between terrain characteristics and landscape types in terrain-complex areas can help reveal the mechanisms underlying the relationships. In this study, Qihe River Basin, situated in the transition zone from the Taihang Mountains to the North-China Plain, was selected as a case study area. First, the spatial variations in the relief amplitudes(i.e.,high-amplitude terrain undulations) were analyzed. Second, the effects of relief amplitudes on the landscape patterns were indepth investigated from the perspectives of both landscape types and landscape indices. Finally, a logistic regression model was employed to examine the relationships between the landscape patterns and the influencing factors(natural and human) at different relief amplitudes. The results show that with increasing relief amplitude, anthropogenic landscapes gradually give in to natral landscapes. Specifically, human factors normally dominate the gentle areas(e.g., flat areas) in influencing the distribution of landscape types, and natural factors normally dominate the highly-undulating areas(e.g., moderate relief areas). As for the intermediately undulating areas(i.e.,medium relief amplitudes), a combined influence of natural and human factors result in the highest varieties of landscape types. The results also show that in micro-relief areas and small relief areas where natural factors and human factors are more or less equally active,landscape types are affected by a combination of natural and human factors.The combination leads to a high fragmentation and a high diversity of landscape patterns. It seems that appropriate human interferences in these areas can be conducive to enhancing landscape diversity and that inappropriate human interferences can aggravate the problems of landscape fragmentation.Jingjing ZHANG Wenbo ZHU Fang ZHAO Lianqi ZHU Maojuan LI Ming ZHU Xiaodong ZHANG 2018Science China Earth Sciences2018,61,4:13
18Synthesis of a novel triple-site diphosphinoamine (PNP) ligand and its applications in ethylene tetramerization显示文摘A novel triple-site diphosphinoamine (PNP) ligand was synthesized and characterized. In combination with Cr(III) and methylaluminoxane (MAO), it generated active catalytic systems for ethylene tetramerization toward 1-octene with high catalytic activity and long lifetime. The effects of reaction temperature, molar ratio of Al/Cr and molar ratio of ligand/Cr on catalytic activity and selectivity to 1-octene were studied with reaction kinetics of the catalytic system for ethylene tetramerization described. At the Al/Cr molar ratio of 100, the catalytic activity is up to 2.29×106 g·mol-1 (Cr)·h-1 and the selectivity to 1-octene is 49.65 wt%.MAO GuoLiang NING YingNan HU WenBo LI ShanMing SONG XianFeng NIU Bo JIANG Tao 2008Chinese Science Bulletin2008,53,22:11
19Preface显示文摘Founded in 1935, the Institute of Mathematical Statistics (IMS) is an international professional and scholastic society devoted to the development, dissemination, and application of statistics and probability.IMS China, established in 2007, promotes the participation of Chinese scholars in activities of the Institute of Mathematical Statistics.Chen, Zhen-Qing Li, Wenbo Li, Zenghu 2012Science China Mathematics2012,55,11:11
20Study on BaTiO_3 films prepared by AC power microarc oxidation显示文摘BaTiO3 films were prepared by microarc oxidation (MAO) with an in-house built alternating current (AC) power supply in Ba(OH)2 solution in this study. The surface morphology, combinability with the substrate and phase composition of the films were investigated by XRD, SEM and TEM. The BaTiO3 films were annealed at a temperature range of 900 to 1200℃ and phase compositions were tested thereafter. The results showed that the BaTiO3 films were mainly composed of the primitive hexagonal phase with relatively small amount of tetragonal and amorphous phases. Moreover, the amount of amorphous phase decreased with the time of annealing. The transformation of BaTiO3 from hexagonal structure to tetragonal stucture became obvious until the annealing temperature reached 1200℃. The film consisted mainly of BaTiO3 tetragonal structure with ferroelectric property. The influence of annealing on surface morphology and mechanism of phase transformation of the films were also discussed.HUANG WenBo, LI WenFang & HAN Bing College of Material Science and Engineering, South China University of Technology, Guangzhou 510640, China 2009Science China(Technological Sciences)2009,52,8:11
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