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Variations of near-surface atmospheric CO_(2)and H_(2)O concentrations during summer on Muztagata

Science china Earth sciences 2006年第1期49卷 18-26页

作者： XU Baiqing1,2, YAO Tandong1,2, LU Anxin2, GUO Xuejun, LIU Xianqin2 & LI Zhen2 1. Laboratory of Environment and process on Tibetan Plateau, institute of Tibetan Plateau Research, chinese academy of sciences, beijing 100085, china 2. Key Laboratory of Cryosphere and Environment, Jointly Established by Cold and Arid Regions Environmental and Engi-neering Research institute and institute of Tibetan Plateau Research, chinese academy of sciences and chinese academy of Meteorological sciences, china Meteorological Administration, Lanzhou 730000, china 1. Laboratory of Environment and process on Tibetan Plateau Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China 2. Key Laboratory of Cryosphere and Environment Jointly Established by Cold and Arid Regions Environmental and Engineering Research Institute and Institute of Tibetan Plateau Research Chinese Academy of Sciences and Chinese Academy of Meteorological Sciences China Meteorological Administration Lanzhou 730000 China

Expeditions during the summers of 2002 and 2003 implemented continuous monitoring of near-surface (2 m height) atmospheric CO2 and H2O concentrations at the 4500 m elevation on Muztagata. The resultant data sets reveal a slight decrease of CO2 concentrations (of about 5 μmol·mol?1) and changes in the diurnal variations from the end of June to the middle August. The daily maximum CO2 concentrations occur between 02:30―05:30 AM (local time) and the minimum levels occur between 12:00―15:30 PM. The atmospheric CO2 concentrations in the summer of 2002 were around 5 μmol·mol?1 lower than those during the same period of 2003, whereas the diurnal amplitude was higher. In contrast, we found that the daily mean atmospheric H2O content in 2003 was much lower than that in 2002 and there exists a striking negative correlation between CO2 and H2O con-centrations. We therefore suggest that the near-surface atmospheric CO2 concentration is affected not only by photosynthesis and respiration, but also by the air H2O content in the glaciated region around Muztagata.

关键词： atmospheric CO2 and H2O concentration, continuous monitoring, glaciation region, Muztagata.

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Energy Transfer among Chlorophylls in Trimeric Light-harvesting Complex Ⅱ of Bryopsis corticulans

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Acta Biochimica et Biophysica Sinica 2006年第5期38卷 310-317页

作者： Su-Juan ZHANG~(1,2*)Shui-Cai WANG~2 Jun-Fang HE~2 Hui CHEN~3 1 institute of Photonics and Photo-Technology,Northwest University,Xi'an 710069,china 2 State Key Laboratory of Transient Optics and Photonics,Xi 'an institute of Optics and Precision Mechanics,chinese academy of sciences,Xi'an 710068.china 3 Laboratoty of Photosynthesis Basic Research,institute of Botany,chinese academy of sciences,beijing 100093,china institute of Photonics and Photo-Technology Northwest UniversityXi'an 710069 China State Key Laboratory of Transient Optics and Photonics Xi'an Institute of Optics and Precision Mechanics Chinese Academy of SciencesXi'an 710068 China Laboratory of Photosynthesis Basic Research Institute of Botany Chinese Academy of SciencesBeijing 100093 China

A study on energy transfer among chlorophylls（Chls）in the trimeric unit of the major light-harvesting complex Ⅱ（LHC Ⅱ）from Bryopsis corriculan,was carried out using time-correlated singlephoton *** the chlorophyll Q region of LHC Ⅱ,six molecules characterized as Chlb628,Chlb646,Chlb652654,657,Chla664666,Chla674677.680and Chla682683were discriminated according to their absorption spectrumand fluorescence emission ***,excited by pulsed light of 628 nm,fluorescence kinetics spectrain the chlorophyll Q region were *** accordance with the principles of fluorescence kinetics,thesekinetics data were analyzed with a multi-exponential *** constants on energy transfer were *** overwhelming percentage of energy transfer among chlorophylls undergoes a process longer than 97picoseconds（ps）,which shows that,before transferring energy to another Chl,the excited Chl might convertenergy to vibrations of a lower state with different multiplicity（intersystem crossing）.Energy transfer at thelevel of approximately 10 ps was also obtained,which was interpreted as the excited Chls may go throughinternal conversion before transferring energy to another *** with a higher standard deviation,timeconstants at the femtosecond level can not be entirely excluded,which can be attributed to the ultrafastprocess of direct energy *** to the arrangement and direction of the dipole moment of Chls inLHC Ⅱ,the probability of these processes is *** fluorescence lifetimes of Chlb652654,657,Chla664666,Chla674677.680and Chla682683were determined to be 1.44ns,1.43 ns,636 ps and 713 ps,*** of energy dissipation in the pathway of fluorescence emission were no more than 40% in thetrimeric unit of LHC Ⅱ.These results are important for a better understanding of the relationship between thestructure and function of LHC Ⅱ.

关键词： energy transfer LHC Ⅱ transient spectrum fluorescence kinetics

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Energy functionals and killing transform

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chinese Science Bulletin 1997年第19期42卷 1593-1596页

作者： YING JiangangDepartment of Mathematics, Zhejiang University, Hangzhou 310027, china Istitute of Applied Mathematics, chinese academy of sciences, beijing 100080, china Department of Mathematics Zhejiang University Hangzhou China Istitute of Applied Mathematics Chinese Academy of Sciences Beijing China

LET X=（Xt,Px） be a right Markov process with state space （E,ε）, semigroup （P1） andresolvent （Uq）. As in ref.[1, 2], we denote by Excq（X ）, Disq（X） and Conq（X） thecones of excessive, dissipative, conservative measures of X, respectively, and by Sq（X） thecone of excessive functions of X. By convention we drop the superscript q when it is zero. LetMF be the set of all exact multiplicative functional of X. For any given M∈MF, writeEM:= {x∈E:PM0 = 1 = 1} and SM: = inf} t>0: M1= 0 } for the set of

关键词： right processes multiplicative functionals Revuz measures energy functional capacity.

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PARTICLE METHODS FOR COMPLEX FLOWS IN CHEMICAL engineering ——THE PSEUDO-PARTICLE APPROACH

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Particuology 2005年第Z1期 58-59页

作者： Wei GE and Jinghai LI Multi-Phase Reaction Laboratory, institute of process engineering, chinese academy of sciences, beijing 100080, P. R. china

The multi-scale structures of complex flows in chemical engineering have been great challenges to the design and scaling of such systems, and multi-scale modeling is the natural way in response. Particle methods (PMs) are ideal constituents and powerful tools of multi-scale models, owing to their physical fidelity and computational simplicity. Especially, pseudo-particle modeling (PPM, Ge & Li, 1996; Ge & Li, 2003) is most suitable for molecular scale flow prediction and exploration of the origin of multi-scale structures; macro-scale PPM (MaPPM, Ge & Li, 2001) and similar models are advantageous for meso-scale simulations of flows with complex and dynamic discontinuity, while the lattice Boltzmann model is more competent for homogeneous media in complex geometries; and meso-scale methods such as dissipative particle dynamics are unique tools for complex fluids of uncertain properties or flows with strong thermal fluctuations. All these methods are favorable for seamless interconnection of models for different scales. However, as PMs are not originally designed as either tools for complexity or constituents of multi-scale models, further improvements are expected. PPM is proposed for microscopic simulation of particle-fluid systems as a combination of molecular dynamics (MD) and direct simulation Monte-Carlo (DSMC). The collision dynamics in PPM is identical to that of hard-sphere MD, so that mass, momentum and energy are conserved to machine accuracy. However, the collision detection procedure, which is most time-consuming and difficult to be parallelized for hard-sphere MD, has been greatly simplified to a procedure identical to that of soft-sphere MD. Actually, the physical model behind such a treatment is essentially different from MD and is more similar to DSMC, but an intrinsic difference is that in DSMC the collisions follow designed statistical rules that are reflection of the real physical processes only in very limited cases such as dilute gas. PPM is idea

关键词： multi-scale method particle method pseudo-particle modeling multi-phase flow

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NEW WIND WAVE GROWTH RELATIONS

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Journal of Hydrodynamics 2004年第5期16卷 608-614页

作者： WUShu-ping HOUYi-jun YINBao-shu instituteofOceanology ChineseAcademyofSciencesQingdao266071China

In the present paper combining the relationship between wave steepness andwave age with the significant wave energy balance equation for wind wave, a new wind wave growthrelation is presented. Comparisons with the other existing wind wave growth relations show that theresults in present paper accord better with the wind wave growth process.

关键词： relationship between wave steepness and wave age wind wave energy balanceequation new wind wave growth relation

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Desulfurization metabolite of Rhodococcus erythropolis LSSE8-1 and its related desulfurizational gene fragments

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chinese Science Bulletin 2003年第24期48卷 2703-2709页

作者： GOU Zhongxuan, LUO Mingfang, LI Xin, XING Jianmin & LIU Huizhou Laboratory of Separation Science and engineering, State Key Laboratory of Biochemical engineering, institute of process engineering, chinese academy of sciences, beijing 100080, china Correspondence should be addressed to Liu Huizhou (e-mail: hzliu@ ***) Laboratory of Separation Science and engineering State Key Laboratory of Biochemical Engineering Institute of Process Engineering Chinese Academy of Sciences Beijing

Rhodococcus erythropolis LSSE8-1 is a newly isolated biodesulfurizaion strain from the soil of Chishui gas field, Guizhou Province, china. The analysis of its metabo-lism product shows that the strain is a kind of biocatalyst able to oxidize dibenzothiophene (DBT) to 2-hydroxydi- phenyl (HBP), and therefore the sulfur in DBT is selectively removed. By using DBTO2 (dibenzothiophene 5,5-dioxide) as substrate, both DBT and HBP are found in the culture, which shows that the reaction from DBT to DBTO2 is re-versible in the cell. While using 0.5 mmol/L DBT as control, 0.01—0.4 mmol/L DBTO2 shows poisonous effect to the cell, which will explain why there is no DBTO2 accumulation in the process of biodesulfurization. After treatment by lysozme, the plasmid DNA of the strain is isolated by alkaline method to be used as the template of PCR reaction. Three dsz gene fragments of 1.3, 1.0 and 1.2 kb respectively were amplified. Each fragment is ligate with PGEM-T vector, and cloned into E. coli. DH5. The clone DNA is sequenced and the result shows that dsz related genes are highly conservative. The identities of dszA and dszB with respect to IGTS8 are 100%, and the identity of dszC with that of IGTS8 is 99%.

关键词：天然气田贵州二苯并噻吩 DBT 硫 DNA 大气污染污染治理

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小批量生产过程中产品质量控制的研究

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系统工程理论与实践 2002年第5期22卷 24-30页

作者：张文生中国科学院软件研究所

借助支持向量机技术解决了下面三个问题 :1 .在给定核函数的前提下 ,客观地、系统地给出一组增强输入模式 ,进而构造指出向量机网络 ,求出小批量数据所遵循的规律 ;2 .通过理论分析说明 ,该方法不仅能控制学习结果对测试样本的误差 ,而... 详细信息

借助支持向量机技术解决了下面三个问题 :1 .在给定核函数的前提下 ,客观地、系统地给出一组增强输入模式 ,进而构造指出向量机网络 ,求出小批量数据所遵循的规律 ;2 .通过理论分析说明 ,该方法不仅能控制学习结果对测试样本的误差 ,而且能提高学习结果的泛化能力 ,从而避免 BP学习过程的缺陷 ,;3.通过求解小批量生产过程产品质量规律的实例 ,验证了上述结果。

关键词：小批量生产过程产品质量控制函数型连接网络支持向量机现代制造业

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Relationships between δ ^(18)O in summer precipitation and temperature and moisture trajectories at Muztagata, western china

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Science china Earth sciences 2006年第1期49卷 27-35页

作者： YU Wusheng1,2, YAO Tandong1,2, TIAN Lide1,2, LI Zhen2, SUN Weizhen2 & WANG Yu2 1. Laboratory of Environment and process on Tibetan Plateau, institute of Tibetan Plateau Research, chinese academy of sciences, beijing 100085, china 2. Key Laboratory of Cryosphere and Environment, Jointly Established by Cold and Arid Regions Environmental and Engi-neering Research institute and institute of Tibetan Plateau Research, chinese academy of sciences and chinese academy of Meteorological sciences, china Meteorological Administration, CAS, Lanzhou 730000, china 1. Laboratory of Environment and process on Tibetan Plateau Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China 2. Key Laboratory of Cryosphere and Environment Jointly Established by Cold and Arid Regions Environmental and Engineering Research Institute and Institute of Tibetan Plateau Research Chinese Academy of Sciences and Chinese Academy of Meteorological Sciences China Meteorological Administration Lanzhou 730000 China

Based on summer observations of stable isotope of precipitation at Muztagata, western china, during 2002―2003, this paper presents the relationship between δ 18O in precipitation and air temperature, and discusses the effect of moisture transport on δ 18O in precipitation. Results show that air temperature correlates positively with δ 18O in precipitation, and the temperature effect controls the δ 18O of precipitation in this area. The Muztagata region exhibits high δ 18O values in summer precipi-tation, similar to those shown at stations in adjacent regions. According to the results of our model set up to trace the moisture trajectories, the westerlies and local moisture circulation contribute to varia-tions of oxygen isotopes in precipitation. In addition, the impacts of the moisture transport distance, the moisture transport level, and the incursion of the polar air mass also influence the variations of δ 18O in precipitation. The moisture origins and transport mechanisms also contribute to the variation of δ 18O in precipitation at Muztagata.

关键词： Muztagata, δ18O, precipitation, temperature, moisture transport.

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Contributions of phosphatase and microbial activity to internal phosphorus loading and their relation to lake eutrophication

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Science china Earth sciences 2006年第z1期49卷 102-113页

作者： SONG Chunlei, CAO Xiuyun, LI Jianqiu, LI Qingman, CHEN Guoyuan & ZHOU Yiyong institute of Hydrobiology, chinese academy of sciences, Wuhan 430072, china Graduate School of the chinese academy of sciences, beijing 100039, china 1. institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China 2. Graduate School of the chinese academy of sciences Beijing 100039 China

Phosphatase may accelerate the process of lake eutrophication through improving phosphorus bioavailability. This mechanism was studied in three chinese eutrophic shallow lakes (Lake Taihu, Lake Longyang and Lake Lianhua). Phosphatase activity was related to the concentration of soluble reactive phosphorus (SRP) and chlorophyll a. Stability of dissolved phosphatase in reverse micelles may be attributed to molecular size, conformation and active residues of the *** the site with Microcystis bloomed in Lake Taihu, dissolved phosphatase activity was higher and more stable in micelles, SRP concentrations were lower in interstitial water, the contents of different forms of phosphorus and the amounts of aerobic bacteria were lower while respiration efficiency was higher in sediments. Phosphobacteria, both inorganic and organic and other microorganisms were abundant in surface water but rare in sediments. Therefore, internal phosphorus may substantially flux into water column by enzymatic hydrolysis and anaerobic release, together with mobility of bacteria,thereby initiating the bloom. In short, biological mechanism may act in concert with physical and chemical factors to drive the internal phosphorus release and accelerate lake eutrophication.

关键词： dissolved phosphatase, reverse micelle, internal loading, phosphorus form of sediment, microbiology, eutrophication, Microcystis bloom.

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Some characteristics of the atmosphere during an adiabatic process

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Progress in Natural Science:Materials International 2006年第6期16卷 644-648页

作者： GAO Li, LI Jianping and REN Hongli (LASG, institute of Atmospheric Physics, chinese academy of sciences, beijing 100029, china Graduate School of chinese academy of sciences, beijing 100049, china National Climate Center, Laboratory of Climate Studies, china Meteorological Administration, beijing 100081, china) [a]LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China [b]Graduate School of chinese academy of sciences Beijing China [c]National Climate Center Laboratory of Climatic Studies China Meterological Administration Beijing China

Some important characteristics of the atmosphere during an adiabatic process are investigated, which include the invariability of atmospheric entropy range and local surface potential temperature, the conservation of the atmospheric mass intervened between any isentropic surface and the ground, and the isentropic surface intersecting with the ground. The analysis shows that the atmospheric reference state (ARS) for investigation on available potential energy (APE) should be defined objectively as the state which could be approached from the existing atmosphere by adiabatic adjustment, and be related to initial atmospheric state before adjustment. For the initial atmosphere state at any time, its corresponding ARS is different from the one at another time. Based on the above-mentioned conclusions, the reference state proposed by Lorenz cannot be obtained physically, so a new conception, the conditional minimum total potential energy, is put forward in order to objectively investigate atmospheric APE.

关键词： available potential energy adiabatic isentropic surface atmospheric reference state conditional minimum total potential energy.

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