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SYNTHESIS AND CHARACTERIZATION OF NEW STABILIZERS WITH OPTIMAL MOLECULAR WEIGHT

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chinese Journal of Polymer Science 2001年第4期19卷 341-350页

作者： Jiang-qing Pan Institute of Chemistry chinese academy of sciences, beijing 100080{4. chinese Acad Sci Inst Chem Beijing 100080 Peoples R China

Over 2 x 10(8) tons of polymers are produced every year, and a large portion of polymers faces the degradation problem. There are many effective methods to protect polymers against degradation and the addition of stabilizers to polymer remains the most convenient and effective way of enhancing polymer life and performance. In this article, a series of effective stabilizers with optimal molecular weight (MW), including common, monomeric and polymeric stabilizers (antioxidant and light stabilizer) were synthesized using isocyanation, controlled isocyanation, hydrosilylation, epoxide addition, macroreaction of stabilizing functional compounds and polymerization of monomeric stabilizers. The structure and performance of these new stabilizers were characterized by using IR, NMR, MS, UV-spectra, XPS and elemental analysis. The current development of stabilizer synthesis was also reviewed.

关键词： preparation of stabilizer antioxidant hindered amine light stabilizer isocyanation hydrosilylation

Patterns of platinum-group elements in mantle peridotite, granulite xenoliths and basalt in Hannuoba

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chinese Science Bulletin 1999年第18期44卷 1676-1681页

作者： CHU Xuelei, LI Xiaolin, XU Jiuhua and LIU Jianming1. The Research Center of Mineral Resources Exploration , chinese academy of sciences , beijing 100101,{4. 2. Institute of Geology , chinese academy of sciences , beijing 100029,{4. 3. Institute of High Energy Physics , chinese academy of sciences , beijing 100817 ,{4. 4. beijing University of Science and Engineering , beijing 100083,{4. Corresponding author The Research Center of Mineral Resources Exploration Chinese Academy of Sciences Beijing China Institute of Geology Chinese Academy of Sciences Beijing China Institute of High Energy Physics Chinese Academy of Sciences Beijing China beijing University of Science and Engineering Beijing China

Neutron activation analysis after preconcentration of nickel sulfide fire assay was used in measurement of Ru, Ph, Pd, Os, Ir, Pt (i.e. PGE elements) and Au concentrations for basalt, mantle and granulite xenoliths in Hannuoba. The chondrite- and primitive mantle-normalized PGE patterns generally exhibit flat (for Iherzolite), negative slope (for harzburgite),

关键词： mantle xenolith granulite xenolith basalt platinum-group element Hannuoba.

Analysis of tandem repeats in the genome of chinese shrimp Fenneropenaeus chinensis

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chinese Science Bulletin 2005年第14期50卷 1462-1469页

作者： KONG Jie1 & GAO Huan2,3 1. Key Laboratory for Sustainable Utilization of Marine Fisheries Re- sources, Ministry of Agriculture, Yellow Sea Fisheris Research Insti- tute, chinese academy of Fishery sciences, Qingdao 266071, china 2. Institute of Oceanology, chinese academy of sciences, Qingdao 266071, china 3. The graduate School of the chinese academy of sciences, beijing 100039, china Key Laboratory for Sustainable Utilization of Marine Fisheries Resources Ministry of Agriculture Yellow Sea Fisheris Research Institute Chinese Academy of Fishery Sciences Qingdao China Institute of Oceanology Chinese Academy of Sciences Qingdao China The graduate School of the chinese academy of sciences Beijing China

Through random sequencing, we found a total of 884.00 base-pairs (bp) of random genomic sequences in the genome of chinese shrimp (Fenneropenaeus chinensis). Using bio-soft Tandem Repeat Finder (TRF) software, 2159 tandem repeats were found, in which there were 1714.mi- crosatellites and 4.5 minisatellites, accounting for 79.4. and 20.6% of repeat sequences, respectively. The cumulative length of repeat sequences was found to be 116685 bp, ac- counting for 13.2% of the total DNA sequence; the cumula- tive length of microsatellites occupied 9.78% of the total DNA sequence, and that of minisatellites occupied 3.4.%. In decreasing order, the 20 most abundant repeat sequence classes were as follows: AT (557), AC (4.1), AG (274., AAT (92), A (56), AAG (28), ATC (27), ATAG (27), AGG (18), ACT (15), C (11), AAC (11), ACAT (11), CAGA (10), AGAA (9), AGGG (7), CAAA (7), CGCA (6), ATAA (6), AGAGAA (6). Dinucleotide repeats, not only in the aspect of the number, but also in cumulative length, were the preponderant repeat type. There were few classes and low copy numbers of repeat units of the pentanucleotide repeat type, which included only three classes: AGAGA, GAGGC and AAAGA. The classes and copy numbers of heptanucleotide, eleven-nucleotide and thirteen-nucleotide primer-number-composed repeats were distinctly less than that of repeat types beside them.

关键词：虾遗传特性遗传基因 DNA

Polyphyly of the fern family Tectariaceae sensu Ching:Insights from cpDNA sequence data

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Science china(Life sciences) 2007年第6期50卷 789-798页

作者： LIU HongMei1,2, ZHANG XianChun1, CHEN ZhiDuan1, DONG ShiYong3 & QIU YinLong4.1 State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, chinese academy of sciences, beijing 100093,{4. 2 graduate University of chinese academy of sciences, beijing 100039,{4. 3 South{4. Botanical Garden, chinese academy of sciences, Guangzhou 510650,{4. 4.Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 4.109-104., USA State Key Laboratory of Systematic Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China graduate University of chinese academy of sciences Beijing 100039 China South china Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China Department of Ecology Evolutionary Biology University of Michigan Ann Arbor MI 48109-1048 USA

Tectariaceae are a pantropical fern family of about 20 genera, among which 8 are distributed in china. The morphological distinctiveness of the family is widely recognized, yet relatively little systematic research has been conducted on members of Tectariaceae. Phylogenetic analyses of chloroplast DNA sequence data (rbcL; atpB) from 15 species representing all 8 genera in china were carried out under parsimony criteria; Bayesian inference. The phylogenetic reconstructions indicated that the fern family Tectariaceae as traditionally circumscribed are polyphyletic. Ctenitis, Dryopsis, Lastreopsis clustered with; should be included within the newly-defined Dryopteridaceae,; Pleocnemia is also tentatively assigned to it. A narrowly monophyletic Tectariaceae is identified, which includes Ctenitopsis, Hemigramma, Pteridrys, Quercifilix,; Tectaria. In the single rbcL analysis, Arthropteris clustered with the above-mentioned monophyletic Tectariaceae. Although further investigations are still needed to identify infrafamilial relationships within the monophyletic Tectariaceae; to redefine several problematic genera, we propose a working concept here that better reflects the inferred evolutionary history of this group.

关键词： Tectariaceae, polyphyly, rbcL, atpB

Teleconnection between the Indian summer monsoon onset and the Meiyu over the Yangtze River Valley

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Science china Earth sciences 2008年第7期51卷 1021-1035页

作者： LIU YunYun1,2,3 & DING YiHui2 1 chinese academy of Meteorological sciences, beijing 100081,{4. 2 National Climate Center, beijing 100081,{4. 3 graduate University of chinese academy of sciences, beijing 10004.,{4. 1. chinese academy of Meteorological sciences Beijing 100081 China 2. National Climate Center Beijing 100081 China 3. graduate University of chinese academy of sciences Beijing 100049 China

Based on the Indian and chinese precipitation data and the NCEP-NCAR reanalysis circulation data, the relationship between the Indian summer monsoon (ISM) onset and the Meiyu over the Yangtze River Valley has been discussed by the methods of correlation analysis and composite analysis. The results show that the date of ISM onset over Kerala in the southwestern coast of the Indian Peninsula is about two weeks earlier than the beginning of the Meiyu over the Yangtze River Valley. After the outbreak of ISM, the teleconnection mode sets up from the western coast of India via the Bay of Bengal (BOB) to the Yangtze River Valley and southern Japan. It is different both in time and space from the telecon- nection mode which is from the northwest of India via the Tibetan Plateau to northern china. The for- mer mode is defined as the "south" teleconnection of the Asian summer monsoon, forming in the pe- riod of ISM onset; while the latter mode is called the "north" teleconnection, mainly occurring in the Asian monsoon culminant period. During the process of the "south" teleconnection’s formation, the Asian monsoon circulation has experienced a series of important changes: ISM onset, the northward movement of the south Asia high (SAH), the onset vortex occurrence, the eastward extension of the stronger tropical westerly belt, and the northeastward jump of the western Pacific subtropical high (WPSH), etc. Consequently, since ISM sets up over Kerala, the whole Asian continent is covered by the upper SAH after about two weeks, while in the mid- and lower troposphere, a strong wind belt forms from the Arabian Sea via the southern India, BOB and the South china Sea (SCS), then along the western flank of WPSH, to the Yangtze River Valley and southern Japan. With the northward moving of the subtropical jet streams, the upper westerly jet stream and the low level jet have been coupled ver- tically over east Asia, while the Yangtze River Valley happens to locate in the ascending motion

关键词： Indian summer monsoon (ISM) the Meiyu over the Yangtze River Valley teleconnection mode

Origin of the Red Earth sequence on the northeastern Tibetan Plateau and its implications for regional aridity since the middle Miocene

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Science china Earth sciences 2006年第5期49卷 505-517页

作者： WANG Xianyan1,7, LU Huayu1,2, JI Junfeg3, WANG Xiaoyong1,7, ZHAO Jingbo4. HUANG Baochun5 & LI Zhen6 1. SKLLQG, Institute of Earth Environment, chinese academy of sciences, Xi’an 710075, china 2. Department of Urban and Resources sciences, Nanjing University, Nanjing 210093, china 3. Department of Earth sciences, Nanjing University, Nanjing 210093, china 4. Department of Geography, Shaanxi Normal University, Xi’an 710062, china 5. Institute of Geology and Geophysics, chinese academy of sciences, beijing 100029, china 6 Department of Geography, Qinghai Normal University, Xining 810008, china 7. graduate School of the chinese academy of sciences, beijing 100039, china 1. SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 7. graduate School of the chinese academy of sciences Beijing 100039 China 2. Department of Urban and Resources sciences Nanjing University Nanjing 210093 China 3. Department of Earth sciences Nanjing University Nanjing 210093 China 4. Department of Geography Shaanxi Normal University Xi’an 710062 China 5. Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 6. Department of Geography Qinghai Normal University Xining 810008 China

The Red Earth deposit around Xining, northeastern Tibetan Plateau, has beenstudied in terms of soil micro-structure, grain-size distribution, major- and trace-elementchemistry and magne-tostratigraphy. Field investigations indicate that the Red Earth sequenceconsists of 25 visually definable yellow-brown and weakly-developed soils interbedded with reddishstrongly-developed soils, and has a similar structure to the aeolian Red Clay deposit on the chineseLoess Plateau. Grain-size analysis shows that the Red Earth deposit is very fine-grained with anegligible sand fraction ( > 63 μm). Thin-section observations under light microscopy show that thedeposit has a clayey texture and the coarse fraction ( > 10 μm) mainly consists of quartz,feldspar and micas. Pyroxene and hornblende were also observed. This mineralogical composition ofthe coarse fraction is similar to that of the Quaternary loess. In addition, all of the mineralgrains are semi angular semi-angular and are generally finer than 63 μm. There is a good agreementbetween the major and minor trace element chemistry of loess-soil units and the Red Earth *** REE distributions of the loess-soil and the Red Earth deposit are similar in shape, withenriched LREE and fairly flat HREE profiles and a clear negative Eu anomaly. The geochemicalcharacteristics of the Red Earth deposit are also identical to those of upper continental crust,thus indicating a wind-blown origin. Magnetostratigraphic investigation shows that onset of the RedEarth deposition predates 11.4.Ma BP (13.6 Ma at a nearby site). The distribution of the reportedMiocene aeolian loess at Qin''an of the Loess Plateau is still unknown. Our results indicate thatthis aeolian deposit had extended to the northeastern Tibetan Plateau by at least the middleMiocene. The similarity of the element geochemistry between the Red Earth deposit and the overlyingloess shows that they may have similar sources and dynamic transport system, and may indicate thatthe

关键词： Red Earth deposit, Northeastern Tibetan Plateau, aeolian deposit, aridity of Asia, the middle Miocene.

Rocky Land Desertification and its Driving Forces in the Karst Areas of Rural Guangxi,Southwest china

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Journal of Mountain Science 2008年第4期5卷 350-357页

作者： LIU Yansui WANG Jieyong DENG Xiangzheng Institute of Geographic sciences and Natural Resources Research Chinese Academy of Science Beijing 100101 China Institute of Geographic sciences and Natural Resources Research Chinese Academy of Science Beijing loolo~ ChinaGraduate University of Chinese Academy of Sciences Beijing 100039 China

With a subtropical climate,Guangxi Zhuang Autonomous Region has a typical karst *** desertification has become a serious environmental issue due to its high vulnerability caused by the joint effect of natural settings and human activities,because of which its eco-environment has been deteriorated in recent years,and farmland has been disappearing sharply at the same ***,in turn,has exacerbated the poverty level in the rural areas of the *** this study,we monitored the spatial distribution of rocky land desertification and its temporal evolution using Landsat TM/ETM images of 1985,1995,2000 and *** also analyzed the driving forces of the desertification and its *** constructing regression models by using all the relevant variables and considering the lagged effects as well as fixed effects,we quantified the exact role of different factors causing rocky land desertification in the study area with some new *** new findings in this study are greatly helpful for preserving,restoring and reconstructing the degraded mountain environment in Guangxi and other karst areas in Southwest china,and also for alleviating poverty in the rural areas in the future.

关键词： Rocky land desertification karstmountain area rural poverty driving force Guangxi Southwest china

Estimation on dynamic release of phosphorus from wind-induced suspended particulate matter in Lake Taihu

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Science china Earth sciences 2004年第8期47卷 710-719页

作者： FAN Chengxin1, ZHANG Lu1,2, QIN Boqiang1, WANG Sumin1, HU Weiping1 & ZHANG Chen1 1. Taihu Lake Laboratory for Ecosystem Research, Nanjing Institute of Geography & Limnology, chinese academy of sciences, Nanjing 210008, china 2. {4. School of chinese academy of sciences, beijing 100039, china 1. Taihu Lake Laboratory for Ecosystem Research Nanjing Institute of Geography & Limnology Chinese Academy of Sciences 210008 Nanjing China 2. graduate School of chinese academy of sciences 100039 Beijing China

Through man-made disturbance experiments, the corresponding relationships be-tween suspended particulate matter (SPM) and wind speed in different lake areas were simu-lated, the physicochemical formal transformation and biological mineralizing and decaying processes of phosphorus in SPM were studied, the contribution of phosphorus transformation to phosphorus loading of the water of Lake Taihu was quantitatively estimated. The results show that about 0.4. t·a-1 loading in Lake Taihu mainly comes from phosphorus-releasing action of SPM in physicochemical transformed to soluble reactive phosphorus (SRP), and the contribution mainly from biological mineralizing and decaying was about 4.5.8 t·a-1, which is equal to 15.0% of the total external loading of Lake Taihu, namely 4.7—7.5 times as much as SRP loading en-tering the lake by the rivers; thus it is the important source in dynamical internal loading of the lake. The determining factors for dynamical internal loading in lakes are organic phosphorus content in suspended solid and its biological transition availability.

关键词： phosphorus release,wind wave disturbance,particulate decaying,dynamical loading,Lake Taihu.

The possible pivotal role of the eastward dust transport from Central Asia in the global temperature decrease

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chinese Science Bulletin 2006年第A01期51卷 1-7页

作者： LIU Mingzhe & WEI Wenshou Xinjiang Institute of Ecology and Geography, chinese academy of sciences, Urumqi 830011, china {4. University of the chinese academy of sciences, beijing 100039, china Chemical Laboratory for Atmosphere, china Meteorological Administration, beijing 100081, china Urumqi Desert Meteorology, china Meteorological Administration, Urumqi 830002, china Grad Univ Chinese Acad Sci Beijing 100039 Peoples R China china Meteorol Adm Chem Lab Atmosphere Beijing 100081 Peoples R China china Meteorol Adm Urumqi 830002 Peoples R China chinese Acad Sci Xinjiang Inst Ecol & Geog Urumqi 830011 Peoples R China

glacial-interglacialgyrations 的出现能与 Milankovitch 理论被解释，这通常被考虑。然而，在理论的一些问题的答案还当前没被导出。在从 CentralAsia 研究东方灰尘运输以后，我们发现了在东方灰尘运输和全球温度减少之间有积极反馈... 详细信息

glacial-interglacialgyrations 的出现能与 Milankovitch 理论被解释，这通常被考虑。然而，在理论的一些问题的答案还当前没被导出。在从 CentralAsia 研究东方灰尘运输以后，我们发现了在东方灰尘运输和全球温度减少之间有积极反馈机制。这在北半球的 thehigh 纬度区域放大太阳的放射变化的效果，并且导致全球冰川的时代的出现。积极反馈机制在北半球的 thehigh 纬度区域以太阳的放射的减小开始。随后，全球温度减少，全球冰川的历元发生，在哪个枢轴的因素是从 CentralAsia 的东方灰尘运输。与积极反馈机制的理论，在 Milankovitch 理论的一些问题能被解决很好。

关键词：冰川间冰期高纬度地区北半球太阳辐射正反馈机制