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Evidence from carbon isotope measurements for biological origins of individual long-chain n-alkanes in sediments from the Nansha Sea,china

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Chinese Science Bulletin 2002年第7期47卷 578-581页

作者： DUAN Yi & WANG ZhipingState Key Laboratory of Gas Geochemistry, lanzhou institute of Geology, Chinese Academy of Sciences, lanzhou 730000, china institute of Environmental Science, Beijing Normal University, Beijing 100875, china State Key Laboratory of Gas Geochemistry Lanzhou Institute of Geology Chinese Academy of Sciences Lanzhou China institute of Environmental Science Beijing Normal University Beijing China

Carbon isotopes are measured for individual long-chain n-alkanes in sediments from the Nansha Sea. The features of carbon isotopic compositions of individual n-alkanes and their origins are studied. The results show that the long-chain n-alkanes have a light carbon isotopic composition and a genetic feature of mixing sources, and low-latitude higher plants and microbes are considered to be their main end member sources. Based on the abundances and carbon isotopic compositions of individual n-alkanes, the fractional contributions of the two end member sources to individual n-alkanes are quantitatively calculated by using a mixing model. The obtained data indicate that the fractional contributions of the two biological sources are different in the three samples. A trend is that the contribution of microbes increases with the depth. These results provide the theory basis and quantitatively studied method for carbon isotopic applied research of individual n-alkanes.

关键词： modern marine sediment individual n-alkane carbon isotopic composition biological source.

Theory of truth degrees of propositions in the logic system Ln^＊

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Science in china(Series F) 2006年第4期49卷 471-483页

作者： LI Jun1,2 & WANG Guojun1,3 1. institute of Mathematics, Shaanxi Normal University, Xi’an 710062, china 2. School of Sciences, lanzhou University of Technology, lanzhou 730050, china 3. research Center for Science, Xi’an Jiaotong University, Xi’an 710049, china institute of Mathematics Shaanxi Normal University Xi’an China School of Sciences Lanzhou University of Technology Lanzhou China research Center for Science Xi’an Jiaotong University Xi’an China

By means of infinite product of uniformly distributed probability spaces of cardinal n the concept of truth degrees of propositions in the n-valued generalized Lu- kasiewicz propositional logic system Ln^＊ is introduced in the present pap.r. It is proved that the set consisting of truth degrees of all formulas is dense in [0,1], and a general expres- sion of truth degrees of formulas as well as a deduction rule of truth degrees is then obtained. Moreover, similarity degrees among formulas are proposed and a pseudo-metric is defined therefrom on the set of formulas, and hence a possible framework suitable for developing ap.r.ximate reasoning theory in n-valued generalized Lukasiewicz propositional logic is established.

关键词： truth degree similarity degree ap.r.ximate reasoning.

Interspecific delimitation and phylogenetic origin of pugionium(Brassicaceae)

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Journal of Systematics and Evolution 2010年第3期48卷 195-206页

作者： 1,2,3Qiu-Shi YU 1Qian WANG 1Ai-Lan WANG 1Gui-Li WU 3Jian-Quan LIU 1(Division of Molecular Ecology,Key Laboratory of Arid and Grassland Ecology,School of Life Science,lanzhou University,lanzhou 730000,china) 2(Minqin National Studies Station for Desert Steppe Ecosystem,Minqin 733300,china) 3(Gansu Desert Control research institute,lanzhou 730070,china) (Division of Molecular Ecology Key Laboratory of Arid and Grassland Ecology School of Life Science Lanzhou University Lanzhou 730000 China) (Minqin National Studies Station for Desert Steppe Ecosystem Minqin 733300 China) (Gansu Desert Control research institute Lanzhou 730070 China)

pugionium(Brassicaceae)is a small genus that occurs in central Asian *** interspecific delimitation and taxonomic treatments of this genus are disputed and its phylogenetic origin remains unknown. In the present study,we examined these issues based on morphological and molecular data obtained for the first *** used statistical methods to examine inter-and intraspecific morphological *** results suggest that only two species,namely *** and ***,can be warranted for all examined populations and specimens,whereas three species(***,***,and ***)should be incorp.r.ted into p. *** delimitation was further supp.r.ed by the molecular data:all populations of ***,p. calcaratum,***,and *** shared the same internal transcribed spacer genotype,whereas those from *** had another *** analyses of pugionium and representative genera of Brassicaceae based on ndhF sequences suggest that this genus is sister to the genus Megacarpaea,which,together,comprise a well-supp.r.ed lineage with Farsetia,Lobularia,Iberis,and Ionopsidium,whereas the two other genera that were previously suggested to be closely related to this genus(Isatis and Bunias)were placed in the other *** further discuss the origin of pugionium and suggest that it probably originated in central Asia when the climate became drier from the late Miocene.

关键词： internal transcribed spacer(ITS) interspecific delimitation morphological variation ndhF phyloge- netic origin pugionium.

Entropy equilibrium equation and dynamic entropy production in environment liquid

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progress in Natural Science:Materials International 2002年第3期12卷 22-26页

作者： HU Yinqiao(Cold and Arid regions Environment and Engineering institute, Chinese Academy of Sciences, lanzhou 730000, china) Chinese Acad Sci Cold & Arid Reg Environm & Engn Inst Lanzhou 730000 Peoples R China

The entropy equilibrium equation is the basis of the nonequilibrium state thermodynamics. But the internal energy implies the kinetic energy of the fluid micelle relative to mass center in the classical entropy equilibrium equation at present. This internal energy is not the mean kinetic energy of molecular movement in thermodynamics. Here a modified entropy equilibrium equation is deduced, based on the concept that the internal energy is just the mean kinetic energy of the molecular movement. A dynamic entropy production is introduced into the entropy equilibrium equation to describe the dynamic process distinctly. This modified entropy equilibrium equation can describe not only the entropy variation of the irreversible processes but also the reversible processes in a thermodynamic system. It is more reasonable and suitable for wider applications.

关键词： nonequilibrium thermodynamics entropy equilibrium equation entropy production irreversible processes environ- ment liquid.

Enthalpy and entropy interaction p.r.meters of sodium chloride with some monosaccharides in water

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Science china Chemistry 2004年第1期47卷 59-66页

作者： ZHUO Kelei, WANG Jianji, BAI Guangyue, YAN Haike & WANG HangingSchool of Chemistry and Environmental Science, Henan Normal University, Xinxiang 453002, china institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, china lanzhou institute of Chemical physics, Chinese Academy of Sciences, lanzhou 730000, china School of Chemistry and Environmental Science Henan Normal University Xinxiang China institute of Chemistry Chinese Academy of Sciences Beijing China lanzhou institute of Chemical physics Chinese Academy of Sciences Lanzhou China

Dilution enthalpies of sodium chloride and some monosaccharides (glucose, galactose, xylose, arabinose, and fructose) in water and mixing enthalpies of aqueous sodium chloride and these monosaccharide solutions were measured by using an improved precision semimicro-titration calorimeter. Transfer enthalpies of sodium chloride from water to aqueous saccharide solutions were evaluated as well as enthalpy interaction p.r.meters of sodium chloride with these monosaccharides in water. Combined with Gibbs energy interaction p.r.meters, entropy interaction p.r.meters were also obtained. The results show that interactions of the saccharides with sodium chloride depend on the stereochemistry of saccharide molecules. These interaction p.r.meters can identify stereochemical structure of saccharide molecules. Keywords sodium chloride - monosaccharide - enthalpy interaction p.r.meter - entropy interaction p.r.meter - calorimetry

关键词： sodium chloride, monosaccharide, enthalpy interaction p.r.meter, entropy interaction p.r.meter, calorimetry.

Are nuclear loci ideal for barcoding plants? A case study of genetic delimitation of two sister species using multiple loci and multiple intraspecific individuals

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Journal of Systematics and Evolution 2011年第3期49卷 182-188页

作者： 1Qian WANG 1,2Qiu-Shi YU 1Jian-Quan LIU* 1(Molecular Ecology Group,Key Laboratory of Arid and Grassland Ecology,College of Life Sciences,lanzhou University,lanzhou 730000,china) 2(State Key Laboratory Breeding Base of Desertification and Aeolian Sand Disaster Combating,Gansu Desert Control research institute,lanzhou 730070,china) (Molecular Ecology Group Key Laboratory of Arid and Grassland Ecology College of Life Sciences Lanzhou University Lanzhou 730000 China) (State Key Laboratory Breeding Base of Desertification and Aeolian Sand Disaster Combating Gansu Desert Control Research Institute Lanzhou 730070 China)

Considerable debate remains as to which DNA region should be used to barcode *** different chloroplast(cp) DNA regions(rbcL,matK,and trnH-psbA) and nuclear ribosomal internal transcribed regions(ITS) have been suggested as suitable barcodes in ***,low-copy nuclear loci were also suggested to be potentially ideal barcode *** aim of the present study was to test the effectiveness of these proposed DNA fragments and five additional low-copy loci(CHS,DET1,COp1,pGIC1,and rpS2;comprising both coding and non-coding regions) in barcoding closely related *** examined the divergences within and between two species of pugionium(Brassicaceae).We failed to find any interspecific variation from three cpDNA fragments with which to discriminate the two ***,a single base mutation in the internal transcribed spacer(ITS) could discriminate between the two species *** found more variations among all individuals of the two species using each of the other five low-copy nuclear ***,only alleles from one locus(DET1) of the five low-copy loci related to ?owering regulations was able to distinguish the sampled individuals into two *** failed to amplify the corresponding fragments out of Brassicaceae using the designed DET1 *** further discussed the discrimination power of different loci due to incomplete lineage sorting,gene ?ow,and species-specific *** results highlight the possibility of using the nuclear ITS as a core or complementary fragment to barcode recent diverged species.

关键词： chloroplast DNA DNA barcoding internal transcribed spacer(ITS) low-copy nuclear loci pugionium.

Temp.r.ture and precipitation trends in Minqin Desert during the p.r.od of 1961-2007

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Journal of Arid Land 2011年第3期3卷 214-219页

作者： ShuJuan ZHU1,2,3,ZhaoFeng CHANG1,2,3 1 Gansu Minqin National Field Observation & research Station on Ecosystem of Desertified rangeland,Minqin 733300,china 2 Key Laboratory of Desertification Combating of Gansu province,lanzhou 733070,china 3 Gansu Desert Control research institute,lanzhou 733070,china Gansu Minqin National Field Observation and research Station on Ecosystem of Desertified rangeland Minqin 733300 China Key Laboratory of Desertification Combating of Gansu province Lanzhou 733070 China Gansu Desert Control research institute Lanzhou 733070 China

This pap.r.analyzed the data of temp.r.ture and precipitation in Minqin,typical desert area in north-west china,during the p.r.od of 1961 2007 by linear *** result indicated that the increasing rate of the mean annual temp.r.ture in Minqin was higher than that of the average of china;and the temp.r.ture in February increased by 3.01oC averagely in the past 47 *** climate in Minqin displayed an evident warming ***,there was no evidently increasing trend of precipitation in the past 47 years,and drought occurred during the whole growing season.

关键词： temp.r.ture precipitation global climate Minqin

reaction Chemistry of W-Mn/SiO2 Catalyst for the Oxidative Coupling of Methane

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Journal of Natural Gas Chemistry 2003年第1期12卷 1-9页

作者： Shuben LiState Key Laboratory for Oxo Synthesis and Selective Oxidation, lanzhou institute of Chemical physics, Chinese Academy of Sciences, lanzhou 730000, china Stt. Key Lab. Oxo Synth./Sel. Oxid. Lanzhou Inst. of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

reaction chemistry of the OCM reaction on W-Mn/SiO_2 catalyst has beenreviewed in this account. Initial activity and selectivity, stability in a long-term reaction,reaction at elevated pressures and a modelling test in a stainless-steel fluidized-bed reactor showthat W-Mn/SiO_2 has promising p.r.ormance for the development of an OCM process that directlyproduces ethylene from natural gas. A study on surface catalytic reaction kinetics and used catalyststructure characterization revealed a possible reason why C_2 and CO_x selectivity changed duringthe long-term reaction. Further improvement of the catalyst composition and prep.r.tion methodshould be a future direction of study on OCM reaction over W-Mn/SiO_2 catalyst.

关键词： W-Mn/SiO_2 catalyst oxidative coupling of methane elevated pressure methane

Dry electrode for the measurement of biopotential signals

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Science china(Information Sciences) 2011年第11期54卷 2435-2442页

作者： WANG Yu 1,2,pEI WeiHua 2,GUO Kai 2,GUI Qiang 2,LI XiaoQian 2,CHEN HongDa 2 & YANG JianHong 11 institute of Microelectronics,School of physical Science and Technology,lanzhou University lanzhou 730000,china 2 State Key Laboratory on Integrated Optoelectronics,institute of Semiconductors,Chinese Academy of Sciences,Beijing 100083,china institute of Microelectronics School of Physical Science and Technology Lanzhou University Lanzhou China State Key Laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing China

This pap.r.introduces a kind of silicon-based dry electrode for measuring biological *** uses microneedle arrays to penetrate into the stratum corneum to reduce skin *** dry electrode requires neither skin prep.r.tion nor the electrolytic gel,is easy to use and causes no skin *** different technologies are chosen to manufacture microneedle arrays of dry *** is deep dry etching combined with isotropic wet *** other is mechanical dicing combined with chemical wet etching (including isotropic wet etching and anisotropic wet etching).Microneedle arrays are coated with metal and divided into 25 mm 2 as dry electrode *** testing shows that the impedance value of dry electrode can be comp.r.ble with that of commercial electrode in the 20 Hz-10 kHz frequency *** steady-state visual evoked potential recording and analysis prove that the dry electrode can be used to detect electroencephalography.

关键词： dry electrode microneedle array dry etching wet etching EEG