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Quantitative relationships between vegetation and several pollen taxa in surface soil from North china

Chinese Science Bulletin 2000年第16期45卷 1519-1523页

作者： LI Yiyin, zhang Xinshi & ZHOU Guangsheng1. Department of Urbon and Environmental sciences, Peking university, {3. 100871, china 2. Laboratory of Quantitative Vegetation Ecology, Institute of Botany, Chinese Academy of sciences, {3. 100093. china 3. school of Urban and Environmental sciences, Northeast Normal university, Changchun 13.024, china Correspondence should be addressed to Li Yiyin Department of Urbon and Environmental sciences Peking University Beijing China school of Urban and Environmental sciences Northeast Normal University Changchun China Laboratory of Quantitative Vegetation Ecology Institute of Botany Chinese Academy of Sciences Beijing China

According to the vegetation investigation and pollen analysis of surface samples sampled along a precipitation gradient of the Northeast china Transect (NECT), several pollen taxa, including Pinus, Betula, Quercus, Tilia, Acer, Ulmus, Artemisia, Chenopodiaceae, Gramineae and Cyperaceae, were chosen to make the regression and correlation analyses. The results indicated that there exists a close relationship between vegetation and pollen taxa in surface samples. The regression parameters for ten taxa in the forests in the eastern part of NECT were different from those in the steppes in the western part. Pinus, Betula, Artemisia and Chenopodiaceae, which have large slope and y-intercept terms, were over-representative taxa. Acer, Gramineae and Cyperaceae, which have small slope and y-intercept terms, were under-representative taxa. Quercus, Tilia and Ulmus whose slope terms have negative correlation with y-intercept terms were equi-representative taxa. The pollen taxa with large slope or large y-intercept

关键词： pollen taxa in surface soil vegetation regression parameters (slope term and y-intercept term) representation Northeast china Transect (NECT).

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Difluoromethyl phenoxathiinium salt: A new general and versatile difluoromethylating reagent with divergent ·CF_(2)H, CF_(2)H^(+), and :CF_(2) reactivities

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Science china Chemistry 2024年第3期67卷 953-962页

作者： Yuan-Qing Gu Hong-Xin Long Dan-Dan zhang mei-Feng Ruan Guo-Kai Liu school of Pharmacy Shenzhen University Medical SchoolShenzhen UniversityShenzhen 518055China

Development of practical and versatile electrophilic difluoromethylating reagent is still a grand challenge so far due to its inherent instability or low ***,we report the design and synthesis of difluoromethyl phenoxathiinium tetrafluoroborate(PT-CF_(2)H^(+)BF_(4)^(-)) as a novel difluoromethylating reagent,which proves to be a bench-stable,general,powerful and versatile reagent with divergent·CF_(2)H,CF_(2)H^(+),and:CF_(2) *** use of this reagent,we demonstrated a vast array of difluoromethyl radical transfer reactions via diverse pathways involving photocatalyst-free visible-light induction,visible-light photoredox catalysis and visible-light mediation single electron transfer of EDA ***,the green and highly effective CF_(2)H^(+) and:CF_(2) transfer reactions were also readily accomplished.

关键词： difluoromethyl phenoxathiinium salt versatile difluoromethylating reagent difluoromethyl radical difluoromthyl cation difluorocarbene

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A New High Quality EAF Charge

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Journal of university of Science and Technology beijing 2001年第1期8卷 20-21页

作者： Jianliang zhang, Yuquan Liu, Zongwang zhang, Jinlin Jia ,Yongmei zhang Metallurgy school, university of Science and Technology beijing, beijing 100083. china Tianjin Iron Corporation, Handan 056000, china Univ Sci & Technol beijing Met Sch Beijing 100083 Peoples R China Tianjin Iron Corp Handan 056000 Peoples R China

In order to solve the problem of the shortage of scrap, especially high quality scrap, granular pig iron, a new substitute for scrap or DRI (direct reduction iron) has been developed. The technical process of decarbonized granular pig iron has been evaluated. The result shows that this new process is superior to direct reduction process in product quality, construction investment, operation flexibility, production efficiency etc. Decarbonized granular pig iron (DGPI) not only can be used as conventional scrap but also can be charged into EAF as high purity burden equivalent to heavy scrap.

关键词： decarbonized granular pig iron scrap DRI

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Reconstruction of the most recent common ancestor sequences of SARS-Cov S gene and detection of adaptive evolution in the spike protein

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Chinese Science Bulletin 2004年第12期49卷 1311-1313页

作者： zhang Yuan1, ZHENG Nan2,3. HAO Pei4,5 & ZHONG Yang6 1. Laboratory of Systematic and Evolutionary Botany, Institute of Bot- any, Chinese Academy of sciences, beijing 100093.{3. 2. College of Life sciences, beijing Normal university, beijing 100875,{3. 3. Institute of Viral Disease Control and Prevention, Chinese CDC, beijing 100052,{3. 4. Bioinformation Center, Shanghai Institutes for Biological sciences, Chinese Academy of sciences, Shanghai 20003.,{3. 5. Shanghai Center for Bioinformation Technology, Shanghai 20023.,{3. 6. school of Life sciences, Fudan university, Shanghai 20043.,{3. 1. Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences 100093 Beijing China 2. College of Life sciences Beijing Normal University 100875 Beijing China 3. Institute of Viral Disease Control and Prevention Chinese CDC 100052 Beijing China 4. Bioinformation Center Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 200031 Shanghai China 5. Shanghai Center for Bioinformation Technology 200235 Shanghai China 6. school of Life sciences Fudan University 200433 Shanghai China

The genome oiganization and expression strategy of severe acute respiratory syndrome coronavirus (SARS-CoV) have been described extensively. As a structural glycoprotein on the virion surface, the spike protein is responsible for binding to host cellular receptors and for the fusion between the viral envelope and the cellular membrane. It also induces neutralizing antibodies in the host and mediates cellular immunity. Previous studies suggested that amino acid replacements in the spike protein coulddramatically alter the pathogenesis and virulence of some coronaviruses. It is therefore reasonable to test the hypothesis that radical amino acid replacements in the spike protein, favored by environmental selective pressure during the process of SARS-CoV interspecific transmission, might make this pathogen adapt to a new host, In this study, we investigated a total of 108 complete sequences of the SARS-CoV S gene from Gen-Bank (until March 23. 2004). After omission of those records containing frame-shift mutations or low quality sequences, e.g. ZJ01, and selection of one sequence for identical records, an alignment of 42 sequences was obtained using the program Clustal-X. Then, we reconstructed the most recent common ancestor (MRCA) sequences of theSARS-CoV S gene and detected the adaptive evolution in the spike protein.

关键词： SARS冠状病毒自适应进化基因表达糖蛋白分子免疫学波峰病毒

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Role of inositol 1,4,5-trisphosphate receptors in α1-adrenergic receptorinduced cardiomyocyte hypertrophy

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Acta Pharmacologica Sinica 2006年第7期27卷 895-900页

作者： Da-li LUO~(2,3.5) Jian GAO~2 Xiao-mei LAN~3.Gang WANG~4 Sheng WEI~4 Rui-ping XIAO~4 Qi-de HAN~3. Department of Pharmacology,school of Chemical Biology & Pharmaceutical sciences,Capital {3. of Medical sciences,beijing 100069,china 3.Institute of Cardiovascular Science at Health Science Center,Peking {3. beijing 100083.china 4 Institute of Molecular Medicine and College of Life Science,Peking {3.,beijing 100871,china Department of Pharmacology School of Chemical Biology & Pharmaceutical Sciences Capital University of Medical Sciences Beijing 100069 China Institute of Cardiovascular Science at Health Science Center Peking University Beijing 100083 China Institute of Molecular Medicine and College of Life Science Peking University Beijing 100871 China

Aim:Intracellular Ca2+plays pivotal roles in diverse cellular functions,includinggene transcription that underlies cardiac remodeling during stress ***,the role of inositol 1,4,5-trisphosphate receptors（IP3.s）in the media-tion of cardiac intracellular Ca2+and hypertrophic growth remains *** with neonatal rat ventricular myocytes suggests that activation of IP3.smay be linked to α1adrenergic receptor（α1AR）increased stereotyped Ca2+sparkoccurrence and global Ca2+***,we hypothesized that Ca2+releasethrough IP3.s was necessary for α1AR-stimulated cardiac ***:We used myoinositol 1,4,5-trisphosphate hexakis（butyryloxymethyl）ester（IP3.M）,a membrane-permeant ester of IP3.to activate IP3.s directly,and Fluo 4/AM tomeasure intracellular Ca2+***:IP3.M(10μmol·L-1)mimicked theeffects of phenylephrine,a selective agonist of α1AR,in increments in local Ca2+spark release（especially in the perinuclear area）and global Ca2+*** importantly,IP3. inhibitors,2-aminoethoxydiphenyl borateand Xestospongin C,abolished the IP3.M-induced Ca2+responses,and signifi-cantly suppressed α1AR-induced cardiomyocyte hypertrophy assayed by cellsize,[3.]leucine incorporation and atrial natriuretic factor gene expression,dur-ing sustained（48 h）phenylephrine ***:These results,therefore,provide cellular mechanisms that link IP3. signaling to α1AR-stimulatedgene expression and cardiomyocyte hypertrophy.

关键词： inositol 1,4,5-trisphosphate receptors Ca2+sparks α1 adrenergic stimulation cardiac hypertrophy

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On the construction of multi-output Boolean functions with optimal algebraic immunity

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Science china(Information sciences) 2012年第7期55卷 1617-1623页

作者： zhang Jie 1,2 ,SONG ShouChao 1 ,DU Jiao 2,3.& WEN QiaoYan 2 1 school of Science,beijing {3. of Posts and Telecommunications,beijing 100876,china 2 State Key Laboratory of Networking and Switching Technology,beijing {3. of Posts and Telecommunications,beijing 100876,china 3.Department of Mathematics,Xinxiang {3.,Xinxiang 453.03.china 1. school of Science Beijing University of Posts and Telecommunications Beijing 100876 China2. State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China3. Department of Mathematics Xinxiang University Xinxiang 453003 China

In this paper,we show a construction of multi-output Boolean functions with optimal algebraic ***,the relationship between the algebraic immunity of a multi-output Boolean function and those of its component functions is *** show that all the component functions,together with their nonzero linear combination,of the multi-output Boolean functions achieved by this construction have optimal algebraic immunity simultaneously.

关键词： algebraic immunity Boolean functions algebraic attacks annihilators

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Sedimentary facies of the Silurian tide-dominated paleo-estuary of the Tazhong area in the Tarim Basin

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Petroleum Science 2008年第2期5卷 95-104页

作者： zhang Jinliang zhang Zhongjie College of Resource Science and Technology Beijing Normal University Beijing 100875 China school of Marine Geo-Science Ocean University of China Qingdao Shandong 266100 China

As the relative sea-level rose, a paleo-estuary was formed by the marine inundation of the braided river incised valley during the period of the lower sub-member of the upper member of the Kalpingtage. formation of the Silurian in the Tarim Basin, west china. Sandstone-mudstone rhythmite, tidal structures and bimodal cross-bedding are common in these deposits, indicating that tides played a significant role in generating the sedimentary structures and the estuary type was tide-dominated. Five depositional facies were grouped： tidal river, sandy and muddy subtidal flat, tidal flat, tidal bar, tidal channel on the basis of lithology, electric properties, rhythmicity, sedimentary structure, fossil and the contact relationship. The sediment distribution showing first fining seaward and subsequent coarsening seaward from head to mouth, implies the two sediment sources in the paleo-estuary. The paleo-estuary of the Tarim Basin is very different from other representative estuaries. The most important distinction is that there are two adjacent estuaries joined by tidal flat onshore and by sandy and muddy subtidal flat in the sea at the same time, while the others only architecture model for the tide-dominated estuary. have one, So the Tazhong paleo-estuary shows a good

关键词： Tarim basin Silurian tide-dominated estuary tidal river tidal bar

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An application of the Riemann-Roch theorem

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Science china Mathematics 2008年第4期51卷 765-772页

作者： WANG ShiKun~1 zhang HuiPing~(2+) 1 KLMM and IAM AMSS Chinese Academy of sciences beijing 100080 {3. 2 school of Information Renmin university of china beijing 100872 {3. 1. KLMM and IAM AMSS Chinese Academy of Sciences Beijing 100080 China 2. school of Information Renmin University of China Beijing 100872 China

Applying the Riemann-Roch theorem,we calculate the dimension of a kind of mero- morphicλ-differentials’ space on compact Riemann *** we also construct a basis of theλ-differentials’ *** the main result,the Cauchy ... 详细信息

关键词： Riemann-Roch theorem λ-differential annulus domain Cauchy integral formula 14C40

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Preparation and properties of a nano TiO_2/Fe_3._4 composite superparamagnetic photocatalyst

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Rare Metals 2009年第5期28卷 423-427页

作者： LI Yuxiang zhang mei GUO Min WANG Xidong school of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China College of Engineering Peking University Beijing 100871 China

Nano TiO2/Fe3.4 composite particles with different molar ratios of TiO2 to Fe3.4 were prepared via sol-gel method. X-ray diffraction, transmission electron microscopy, and vibration sample magnetometry were used to characterize the TiO2/Fe3.4 particles. The photocatalytic activity of the particles was tested by degrading methyl blue solution under UV illumination （254 nm）. The results indicate that with the content of TiO2 increasing, the photocatalytic activity of the composite particles enhances, while the magnetism of the particles decreases. When the molar ratio of TiO2 to Fe3.4 is about 8, both the photocatalytic activity and magnetism of the TiO2/Fe3.4 particles are relatively high, and their photocatalytic activity remains well after repeated use.

关键词： photocatalysis superparamagnetism sol-gel method TiO2 Fe3.4

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Mesozoic thrusts and extensional structures in the Daqingshan orogen, Inner Mongolia, and their temporal and spatial relationship

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Progress in Natural Science:Materials International 2007年第2期17卷 177-186页

作者： QI Guowei, zhang Jinjiang , WANG Xinshe and GUO Lei ( Key Laboratory of Orogenic Belts and Crustal Evolution, Ministry of Education, china school of Earth and Space {3., Peking university, beijing 100871, china Institute of Geology, Chinese Academy of Geological {3., beijing 10003., china) [a]Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education China [b]school of Earth and Space sciences Peking University Beijing China [c]Chinese Academy of Geological sciences Institute of Geology Beijing China

Three large-scale thrusts developed in the Daqingshan orogen, Inner Mongolia, with a northeast-east trending from Louhuashan to Suletu are described in this paper. These northwest-directed thrusts, together with the four tectonic belts (or tectonic sheets) separated by these faults, formed a typical thrusting system. The originally defined Hohhot metamorphic core complex may be a tectonic sheet, making the uppermost tectonic unit of the thrusting system and truncated by the Daqingshan detachment fault on top. The existing tectono-chronological studies showed that the thrusting of this region possibly happened at the same time as the extension along the top detachment fault. This presents that the contraction and extension in Daqingshan orogen were probably simultaneous. The structural pattern of the Daqingshan orogen can be correlated to the Himalayan orogen, and models for simultaneous thrusting and detachment in Himalaya may give a hint for explaining the development of the Daqingshan orogen.

关键词： Daqingshan thrust metamorphic core complex detachment fault contraction-extension transform Himalaya.

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