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Study on the atmospheric photochemical reaction of CF_3 radicals using ultraviolet photoelectron and photoionization mass spectrometer

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Science China chemistry 2008年第4期51卷 316-321页

作者： YAO Li1.2, DU Lin1.2, YIN Shi1.2 & GE MaoFa1.1.beijing National Laboratory for Molecular{1. (BNLMS), State Key Laboratory for Structural chemistry of Unstable and Stable Species, institute of chemistry, chinese academy of sciences, beijing 1.0080, China 2 Graduate University of chinese academy of sciences, beijing 1.0080, China 1. beijing National Laboratory for Molecular{1. (BNLMS) State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China 2. Graduate University of chinese academy of sciences Beijing 100080 China

A study of the atmospheric photochemical reaction of CF3 radical with CO and O2 was performed by using a homemade ultraviolet photoelectron spectrometer-photoionization mass spectrometer (PES- PIMS). The electronic structures and mechanism of ionization and dissociation of CF3OC(O)OOC(O)- OCF3 were investigated. It was indicated that the two bands on the photoelectron spectrum of CF3OC(O)OOC(O)OCF3 are the result of ionization of an electron from a lone pair of oxygen and a fluo- rine lone pair of CF3 group. The outermost electrons reside in the oxygen lone pair. The experimental and theoretical first vertical ionization energy is 1..21.and 1..1.8 eV, respectively, with the PES and OVGF method. They are in good agreement. The photo ionization and dissociation processes were discussed with the help of theoretical calculations and PES-PIMS experiment. After ionization, the parent ions prefer the dissociation of the C-O bond and giving the fragments CF3OCO+ and CF3+. It demonstrated that the ultraviolet photoelectron and photoionization mass spectrometer could be ap- plied widely in the study of atmospheric photochemical reaction.

关键词： photochemical reaction CF3 radical ultraviolet photoelectron and photoionization mass spectroscopy transient species

Improvement of different source function expressions in SWAN model for the Bohai Sea

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Progress in Natural Science:Materials International 2005年第8期15卷 720-724页

作者： YIN Baoshu1., YANG Dezhou1. SHA Rina 1.2 and CHENG Minghua1.1. institute of Oceanology,{1., Qingdao 266071. China 2. Graduate School of the{1., beijing 1.0039, China) institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China. Graduate School of the chinese academy of sciences Beijing 100039 China

The simulating wave nearshore （SWAN） wave model has been widely used in coastal areas, lakes and estuaries. However, we found a poor agreement between modeling results and measurements in analyzing the chosen four typical cases when we used the default parameters of the source function formulas of the SWAN to make wave simulation for the Bohai Sea. Also, it was found that at the same wind process the simulated results of two wind generation expressions （Komen, Janssen） demonstrated a large difference. Further study showed that the proportionality coefficient α in linear growth term of wave growth source function plays an unperceived role in the process of wave development. Based on experiments and analysis, we thought that the coefficient α should change rather than be a constant. Therefore, the coefficient α changing with the variation of friction velocity U*was introduced into the linear growth term of wave growth source function. Four weather processes were adopted to validate the improvement in the linear growth term. The results from the improved coefficient α agree much better with the measurements than those from the default constant coefficient α. Furthermore, the large differences of results between Komen wind generation expression and Janssen wind generation expression were eliminated. We also experimented with the four weather processes to test the new white-capping mechanisms based on the cumulative steepness method. It was found that the parameters of the new white-capping mechanisms are not suitable for the Bohai Sea, but Alkyon's white-capping mechanisms can be applicable to the Bohai Sea after amendments, demonstrating that this improvement of parameter α can improve the simulated results of the Bohai Sea.

关键词： waves SWAN model wave growth source function new proportionality coefficient formula.

Dynamics of morphological changes for mitochondrial fission and fusion

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Science China(Physics,Mechanics & Astronomy) 2010年第4期53卷 680-689页

作者： WANG ShiQi 1.2,4 , FU ChangLiang 1.2 , ZHANG Yan 1.2 , CHEN Quan 3 & LONG Mian 1.2 1.Key Laboratory of Microgravity (National Microgravity Laboratory), beijing 1.01.0, China 2{1. for Biomechanics and Bioengineering, institute of Mechanics, chinese academy of sciences, beijing 1.01.0, China 3 State Key Laboratory of Biomembrane and Membrane Biotechnology, institute of Zoology, chinese academy of sciences, beijing 1.01.1. China 4 institute of Vertebrate Paleontology and Paleoanthropology, chinese academy of sciences, beijing 1.0044, China 1. Key Laboratory of Microgravity (National Microgravity Laboratory) Beijing 100190 China2. Center for Biomechanics and Bioengineering Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China4. Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China3. State Key Laboratory of Biomembrane and Membrane Biotechnology Institute of Zoology Chinese Academy of Sciences Beijing 100101 China

Mitochondria experience continuous fusion and fission in a living cell, but their dynamics remains poorly quantified. Here a theoretical model was developed, upon a simplified population balance equation (PBE), to predict the morphological changes induced by mitochondrial fission and fusion. Assuming that both fission and fusion events are statistically independent, the survival probability of mitochondria staying in the fission or fusion state was formulated as an exponentially-decayed function with time, which depended on the time-dependent distribution of the mitochondrial volume and the fission and fusion rates. Parametric analysis was done for two typical volume distributions. One was Gamma distribution and the other was Gaussian distribution, derived from the measurements of volume distribution for individual mitochondria in a living cell and purified mitochondria in vitro. The predictions indicated that the survival probability strongly depended on morphological changes of individual mitochondria and was inversely correlated to the fission and fusion rates. This work provided a new insight into quantifying the mitochondrial dynamics via monitoring the evolution of the mitochondrial volume.

关键词： mitochondria morphology fission fusion dynamics modeling

Plus cupping degrees do not form an ideal

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Science in China(Series F) 2004年第5期47卷 635-654页

作者： LI Angsheng1.2 & ZHAO Yicheng1.1. institute of Software,{1. academy of sciences,beijing 1.0080,China 2. School of Information sciences,beijing Normal University,beijing 1.0871.China 1. institute of Software Chinese Academy of Sciences 100080 Beijing China 2. School of Information sciences Beijing Normal University 100871 Beijing China

A computably enumerable (c.e.,for short)degree a is called plus cupping,if every c.e. degree x with 0 详细信息

A computably enumerable (c.e.,for short)degree a is called plus cupping,if every c.e. degree x with 0

关键词： computably enumerable set Turing degree definability.

Molecular cloning of growth hormone receptor (GHR) from common carp(Cyprinus carpio L.)and identification of its two forms of mRNA transcripts

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Progress in Natural Science:Materials International 2006年第11期16卷 1156-1163页

作者： SUN Xiaofeng~ 1.2 , GUO Qionglin~1.*, HU Wei~1. WANG Yaping~1.and ZHU Zuoyan~1.1. State Key Laboratory of Freshwater Ecology and Biotechnology, institute of Hydrobiology,{1., Wuhan 430072, China 2. Graduate School of{1., beijing 1.0039, China) [a]State key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Wuhan China China [b]Graduate School of chinese academy of sciences Beijing China

The cDNA of growth hormone receptor (GHR) was cloned from the liver of 2-year common carp (Cyprinus carpio L.) by reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA end (RACE). Its open reading frame (ORF) of 1.06 nucleotides is translated into a putative peptide of 602 amino acids, including an extracellular ligand-binding domain of 244 amino acids (aa), a single transmembrane domain of 24 aa and an intracellular signal-transduction domain of 334 aa. Sequence analysis indicated that common carp GHR is highly homologous to goldfish (Carassius auratus) GHR at both gene and protein levels. Using a pair of gene-specific primers, a GHR fragment was amplified from the cDNA of 2-year common carp, a 224 bp product was identified in liver and a 321.bp product in other tissues. The sequencing of the products and the partial genomic DNA indicated that the difference in product size was the result of a 97 bp intron that alternatively spliced. In addition, the 321.bp fragment could be amplified from all the tissues of 4-month common carp including liver, demonstrating the occurrence of the alternative splicing of this intron during the development of common carp. Moreover, a semi-quantitative RT-PCR was performed to analyze the expression level of GHR in tissues of 2-year common carp and 4-month common carp. The result revealed that in the tissues of gill, thymus and brain, the expression level of GHR in 2-year common carp was significantly lower than that of 4-month common carp.

关键词： growth hormone receptor (GHR) molecular cloning transcript expression analysis common carp.

Astronomical function and date of the Taosi observatory

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Science China(Physics,Mechanics & Astronomy) 2009年第1期52卷 151-158页

作者： WU JiaBi1. CHEN MeiDong2 & LIU CiYuan3 1.National Astronomical Observatories, chinese academy of sciences,{1. 1.001., China 2 institute for the History of Natural Science, chinese academy of sciences,{1. 1.001., China 3 National Time Service center, chinese academy of sciences, Xi’an 71.600, China 1. National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China 2. institute for the History of Natural Science Chinese Academy of Sciences Beijing 100010 China 3. National Time Service center Chinese Academy of Sciences Xi’an 710600 China

The Taosi site in Xiangfen County,Shanxi Province,may be the capital of the King Yao. Archeologists recently discovered a large semi-circular stamped-earth platform, II FJT1.which has a clear and definite pounded-earth central core together with a curved wall perforated by twelve gaps. The platform is said to be an ancient observatory used to determine the seasons by watching the sunrise. Each feature of II FJT1.was precisely measured and the data are reproduced in this paper. An astronomical analysis of slots E2 and E1. was carried out using the azimuths of the slots' centerlines and the vertical angle of the mountain ridge opposite, above which the sun rises. The results show that at present the sun is close to the two slots but does not exactly enter them at summer and winter solstice sunrise. Using 1.C analysis archeologists dated the site to about 21.0 BC. Because of the secular change in the obliquity of the ecliptic,at that date on the summer solstice the half-risen sun would have appeared inside slot E1. just to the right of the centerline,and on the winter solstice the sun would have been exactly on the centerline of slot E2. This result provides compelling proof that II FJT1.is an ancient observatory.

关键词： astro-archeology astro-chronology Taosi culture ancient observatory time service

Isotopic feature and uranium dating of the volcanic rocks in the Okinawa Trough

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中国科学：地球科学英文版 2006年第4期49卷 375-383页

作者： HUANG Peng1.2, LI Anchun1. HU Ningjing2,3, FU Yongtao1. MA Zhibang4 1. institute of Oceanology,{1., Qingdao 266071. China 2. Graduate School of the{1., beijing 1.0039, China 3. institute of Soil Science,{1., Nanjing 21.008, China 4. institute of Geology and Geophysics,{1., beijing 1.0029, China 1. institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China 2. Graduate School of the chinese academy of sciences Beijing 100039 China 3. institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China 4. institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

Volcanic rocks from the northern and middle Okinawa Trough were dated by ura- nium-series dating method. Differential fractions using magnetic procedure were designed to separate samples. New report on the ages and isotopic data of rocks in the northern trough (especially black pumice) was discussed. Based on the uranium dates and Sr-Nd isotopic ratio, magmatic evolution process of the Okinawa Trough was noted. Firstly, there have been wide silicic volcanic activities in the Okinawa Trough from late Pleistocene to present, and the volcanic rocks can be divided into three subgroups. Secondly, magma generally came from PREMA source area under the Okinawa Trough. Magmatic evolution in the northern trough was similar to the middle, but different to the south. Finally, volcanic activities indicated that opening of the southern Okinawa Trough did not happen due to the collision between Luson Arc and Eurasian Plate until the early Pleistocene.

关键词： Okinawa Trough, black pumice, uranium-series dating, Sr-Nd isotopic ratio, magmatic evolution.

Terrestrial transect study on driving mechanism of vegetation changes

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Science China Earth sciences 2008年第7期51卷 984-991页

作者： ZHANG YuJin1.2 & ZHOU GuangSheng1.1.State Key Laboratory of Vegetation and Environmental Change, institute of Botany,{1., beijing 1.0093, China 2 Graduate University of{1., beijing 1.0049, China 1. State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China 2. Graduate University of chinese academy of sciences Beijing 100049 China

In terms of chinese climate-vegetation model based on the classification of plant functional types, to- gether with climatic data from 1.51.to 1.80 and two future climatic scenarios (SRES-A2 and SRES-B2) in China from the highest and the lowest emission scenarios of greenhouse gases, the distribution patterns of vegetation types and their changes along the Northeast China Transect (NECT) and the North-South Transect of Eastern China (NSTEC) were simulated in order to understand the driving mechanisms of vegetation changes under climatic change. The results indicated that the vegetation distribution patterns would change significantly under future climate, and the major factors driving the vegetation changes were water and heat. However, the responses of various vegetation types to the changes in water and heat factors were obviously different. The vegetation changes were more sensi- tive to heat factors than to water factors. Thus, in the future climate warming will significantly affect vegetation distribution patterns.

关键词： driving mechanism vegetation terrestrial transect climatic change plant functional types

Statistical distribution of nonlinear random wave height

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Science China Earth sciences 2006年第4期49卷 443-448页

作者： HOU Yijun1. GUO Peifang1.2, SONG Guiting1.2, SONG Jinbao1. YIN Baoshu1.& ZHAO Xixi1.2 1. institute of Oceanology,{1., Qingdao 266071. China 2. Graduate University of the{1., beijing 1.0039, China 1. institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China 2. Graduate University of the chinese academy of sciences Beijing 100039 China

A statistical model of random wave is developed using Stokes wave theory of water wave dynamics. A new nonlinear probability distribution function of wave height is presented. The results indicate that wave steepness not only could be a parameter of the distribution function of wave height but also could reflect the degree of wave height distribution deviation from the Rayleigh distribution. The new wave height distribution overcomes the problem of Rayleigh distribution that the prediction of big wave is overestimated and the general wave is underestimated. The prediction of small probability wave height value of new distribution is also smaller than that of Rayleigh distribution. Wave height data taken from East China Normal University are used to verify the new distribution. The results in- dicate that the new distribution fits the measurements much better than the Rayleigh distribution.

关键词： Random ocean wave, nonlinearity, wave height distribution.