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science{1.(Technological sciences) 2004年第2期47卷 186-190页

作者： CHEN Zhenqiang1.2.,zhang Ge1.SHEN Hong{1.an1.HUANG Chenghui1.& LIU Wen1.1.Fujian institute of Research on the Structure of Matter,chinese academy of sciences,Fu{12. 350002.china 2.College of science and Engineering,Jinan University,guangzhou 51.632.china 1. Fujian institute of Research on the Structure of Matter Chinese Academy of Sciences 350002 Fuzhou China 2. College of science and Engineering Jinah University 510632 Guangzhou China

The principal refractive indices and the thermal refractive index coefficients for Be3Al2.i6O1. crystal doped with 1.01.t% Cr2.3 have been accurately measured by the auto-collimation method at wavelengths of 0.488, 0.53975, 1.064, 1.0795 and 1.341. μm, and temperatures of 308.2. 32..6, 359.1.and 395.4 K respectively. Based on the measured results of principal indices of 0.488, 0.632., 1.0795 and 1.341.μm, the Sellmeier’s equations and the thermal refractive index coefficients have been obtained, and the result has been proven to be accurate by error analysis.

关键词： Cr3+: Be3Al2.i6O1. crystal, refractive index, thermal coefficient.

Indoor imitation experimental study on driving factors of rainfall-runoff process

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science{1. Earth sciences 2005年第3期48卷 417-428页

作者： zhang Shifeng1. LIU Changming 1. {1. Jun1. TAN Ge 1. LI Lin1. LIU Caitang1. zhou Changqing 1.& GUO Lei2.1. institute of Geographic {12.s and Natural Resources Research, chinese academy of sciences, Beijing 1.01.1. china 2. College of Water Resources and Hydropower Engineering, Wuhan University, Wuhan 430072. china 1. institute of Geographic {1.s and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. College of Water Resources and Hydropower Engineering Wuhan University 430072 Wuhan China

The driving actions of rainfall-runoff process can be attributed to two aspects. The first is the influence of precipitation process, and the second is that of the ground pad. The re- search results of 1.9 indoor experiments conducted to imitate rainfall-runoff process indicate that both precipitation duration and intensity play important roles in affecting confluence lag time, which is obviously inconsistent with the traditional hypotheses. The nonlinear relationship is of great significance to the confluence curve especially when the precipitation duration is less than the total confluence time or the precipitation intensity is small. Therefore it can be concluded that the unit hydrograph (UH) can be applied to rainfall-runoff process imitation in the humid areas in the south china region. However, the UH application should be strictly modified in accordance with precipitation conditions in the arid and semiarid region of north china where the precipitation duration is short and the intensity is unstable. It will be hard to get ideal imitation results if the UH is applied blindly without considering specific conditions in the north china region. This also explains the unsatisfactory imitation results caused by using various hydrological models in the north china region. When the precipitation duration is short, and the watershed has not reached total watershed concentration, the characteristics of confluence change greatly, which reflects the actual situation in the north china region. Therefore necessary nonlinear corrections should be made when UH is applied. If the duration is longer than the total confluence time and the balance between pondage and discharge is stricken, the imitation research results will be applicable to both rainfall-runoff relation with longer duration in the south china region and the basic theoreti- cal research on runoff generation and concentration. On conditions of adequate rainfall, peak discharge is in linear relationship with inten

关键词： rainfall-runoff, driving factors, indoor imitation, experiment.

Electrical control of excitonic oscillator strength and spatial distribution in a monolayer semiconductor

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Nano Research 2024年第9期17卷 8424-8430页

作者： Yanming wang Junrong {1. Tianhua Ren Meng {2. Long Fang {2.ngyi wang Xingwang {1. Kai {1. Junyong wang School of Nano-Tech and Nano-Bionics University of Science and Technology of ChinaHefei 230026China CAS Key Laboratory of Nanophotonic Materials and Devices&Key Laboratory of Nanodevices and Applications i-LabSuzhou Institute of Nano-Tech and Nano-Bionics(SINANO)Chinese Academy of SciencesSuzhou 215123China institute of Applied Physics and Materials Engineering University of MacaoTaipaMacao 999078China College of New Energy Inner Mongolia University of TechnologyHohhot 010051China

Electrical modulation of luminescence is significant to modern light-emitting *** transition metal dichalcogenides are emerging direct-bandgap luminescent materials with unique excitonic properties,and the multiple exciton complexes provide new opportunities to modulate the property of luminescence in atomically thin ***,we report an electrical control of exciton emission in the oscillator strength and spatial distribution of excitons in a monolayer *** modulation of excitonic emission intensity with a degree of modulation of~92.has been demonstrated by an electric field at room *** spatial carrier redistribution tuned by a lateral electric field results in distinct excitonic emission patterns by *** modulation approach to exciton oscillator strength and distribution provides an efficient way to investigate the exciton diffusion dynamics and to construct electrically tunable optoelectronic devices.

关键词： monolayer semiconductor exciton electrical modulation spatial distribution

Geophysical survey on the tectonic and sediment distribution of Qinghai Lake basin

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science{1. Earth sciences 2006年第8期49卷 851-861页

作者： AN Zhisheng1, wang Ping2. SHEN Ji3, zhang Yi{2.ng2. zhang Peizhen4, wang Sumin3, LI {2.oqiang1, SUN Qianli1, SONG Yougui1, AI Li1, zhang Yechun2. JIANG Shaoren2. LIU Xingqi3 & wang Yong31. institute of Earth Environment, chinese academy of sciences (CAS), Xi’an 710075, china 2. South china Sea institute of Oceanology, CAS, guangzhou 510301, china 3. Nanjing institute of Geography and Limnology, CAS, Nanjing 2.0008, china 4. institute of Geology, china Earthquake Administration, Beijing 10002., china 1. institute of Earth Environment Chinese Academy of Sciences (CAS) Xi’an 710075 China 2. South china Sea {1. of Oceanology CAS Guangzhou 510301 China 3. Nanjing institute of Geography and Limnology CAS Nanjing 210008 China 4. institute of Geology China Earthquake Administration Beijing 100029 China

The intensive geophysical survey of Qinghai Lake reveals the buried depth of lake sediments and their distribution features. The result indicates that there are three important inter- phases of Qinghai Lake sediments: T1.is the rife interphase of the lake, above which sediments are spread all over the lake basin with roughly the same thickness; T5 is the interphase from which the neotectonic sedimentary cycle begins, and its above sedimentary environment is relatively stable; Tg is the base of the lake basin. Five west-northwest (WNW) fault belts defined the tectonic structure of Qinghai Lake basin: the central hunch around Haixin Shan with two subbasins both in its north and south. The thickness of the lake sediments varies at different places, the thickest sediments are found within the two subbasins. According to the depth that the Sparker System can reach, sediment in the northern subbasin is deeper than 560 m, while sediment in the southern subbasin is deeper than 700 m. The correlation between the seismic sequence stratigraph and the lithology of onshore core shows that Qinghai Lake sediments consist of muddy silt, clay silt, silty clay, gravel silty clay, etc.

关键词： sediment, geophysical survey, Qinghai Lake.

Fine mapping and cloning of the sterility gene Bra2.s in nonheading chinese cabbage(Brassica rapa ***)

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Journal of Integrative Agriculture 2024年第4期23卷 1195-1204页

作者： Liping Song xia Li Liguang Tang Chuying {1. Bincai {2. Changbin Gao Yanfeng Xie Xueli zhang Junliang {2. Chufa Lin Aihua {2. Wuhan Vegetable Research institute Wuhan Academy of Agricultural SciencesWuhan 430345China Biotechnology and Genetic Resources institute Yunnan Academy of Agricultural SciencesKunming 650000China

The application of a male-sterile line is an ideal approach for hybrid seed production in non-heading chinese cabbage(Brassica rapa ***).However,the molecular mechanisms underlying male sterility in *** are still largely *** previously obtained the natural male sterile line WS2.-3 of non-heading chinese cabbage and located the male sterile locus,Bra2.s,on the A2.*** observations revealed that the male sterility of WS2.-3 resulted from disruption of the meiosis process during pollen *** mapping of Bra2.s delimited the locus within a physical distance of about {2.9 kb on the A2.chromosome of *** Bra039753 gene encodes a plant homeodomain(PHD)-finger protein and is considered a potential candidate gene for ***039753 was significantly downregulated in sterile line WS2.-3 compared to the fertile line at the meiotic anther *** analysis of Bra039753 identified a 369 bp fragment insertion in the first exon in male sterile plants,which led to an amino acid insertion in the Bra039753 *** addition,the 369 bp fragment insertion was found to cosegregate with the male sterility *** study identified a novel locus related to male sterility in non-heading chinese cabbage,and the molecular marker obtained in this study will be beneficial for the marker-assisted selection of excellent sterile lines in non-heading chinese cabbage and other Brassica crops.

关键词： non-heading chinese cabbage male sterility Bra2.s fine mapping PHD-finger protein

Heat flow pattern,base of methane hydrates stability zones and BSRs in Shenhu Area,northern South china Sea

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Acta Oceanologica Sinica 2011年第1期30卷 59-67页

作者： zhang Yi HE Lijuan {1. Jiyang XU Xing SHA Zhibing GONG {2.ehua {1. Hongbing LIANG Jinqiang institute of Geology and Geophysics Chinese Academy of Science Beijing 100029 China Graduate University of the chinese academy of sciences Beijing 100049 China guangzhou Marine Geological Survey Guangzhou Guangdong 510760 China

Using the collected 433 heat flow values, we estimated the bases of methane hydrate stability zone （BHSZ）, in northern South china Sea （NSCS）. Through comparing BHSZs with the depths of bottom simulating reflectors （BSRs）, in Shenhu Area （SA）, we found that there are big differences between them. In the north of SA, where the water depth is shallow, many slumps developed and the sedimentation rate is high, it appears great negative difference （as large as -1.2.）. However, to the southeast of SA, where the water depth is deeper, sedimentation rate is relatively low and uplift basement topography exists, it changes to positive difference （as large as ＋45%）. The differences change so great, which haven＇t been observed in other places of the world. After considering the errors from the process of heat flow measurement, the BSR depth, the relationship of thermal conductivity with the sediments depth, and the fluid flow activities, we conclude that the difference should be not caused by these errors. Such big disagreement may be due to the misunderstanding of BSR. The deviant ＂BSRs＂ could represent the paleo-BSRs or just gas-bearing sediment layers, such as unconformities or the specific strata where have different permeability, which are not hydraterelated BSRs.

关键词： methane hydrate BSR base of methane hydrate stability zone slump heat flow

DNA barcoding:species delimitation in tree peonies

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science{1.(Life sciences) 2009年第6期52卷 568-578页

作者： zhang JinMei1.2.{1. JianXiu1.2.xia Tao1.2.& zhou ShiLiang1.1.tate Key Laboratory of Systematic and Evolutionary Botany,institute of Botany,the chinese academy of sciences,Beijing 1.0093,{12. 2.raduate School of the chinese academy of sciences,Beijing 1.0039,{12. 1. State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany the Chinese Academy of Sciences Beijing 100093 China 2. Graduate School of the chinese academy of sciences Beijing 100039 China

Delimitations of species are crucial for correct and precise identification of *** "spe-cies" is more a subjective than an objective concept in taxonomic practice due to difficulties in revealing patterns of infra-or inter-specific *** phylogenetic studies at the population level solve this problem and lay a sound foundation for DNA *** this paper we exemplify the necessity of adopting a phylogenetic concept of species in DNA barcoding for tree peonies(Paeonia ***).We used 40 samples representing all known populations of rare and endangered species and several populations of widely distributed tree *** currently recognized species and major variants have been included in this *** chloroplast gene fragments,***,rps1.-trnQ,trnL-F and trnS-G(a total of 5040 characters,96 variable and 69 parsimony-informative characters) and one variable and single-copy nuclear GPAT gene fragment(2.93?2.0}7 bp,2.9 variable and 1.8 parsi-mony-informative characters) were used to construct phylogenetic relationships among the *** evolutionary lineages revealed by the nuclear gene and the chloroplast genes are inconsistent with the current circumscriptions of ***,***,***,and *** based on *** inconsistencies come from(1. significant chloroplast gene divergence but little nuclear GPAT gene divergence among population systems of *** + ***,and(2. well-diverged nuclear GPAT gene but little chloroplast gene divergence between *** and *** incongruence of the phylogenies based on the chloroplast genes and the nuclear GPAT gene is probably due to the chloro-plast capture event in evolutionary history,as no reproductive barriers exist to prevent inter-specific *** also evaluated the suitability of these genes for use as DNA barcodes for tree *** variability of chloroplast genes among well-defined species or population systems of a specie

关键词： DNA barcoding evolution Paeonia phylogeny species concept

Occurrence and possible sources of antibiotic resistance genes in seawater of the South china Sea

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Frontiers of Environmental science & Engineering 2024年第9期18卷 27-38页

作者： Jian Lu Jun Wu Cui zhang Jianhua {1. {2. He CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone Research(YIC)Chinese Academy of Sciences(CAS)Shandong Key Laboratory of Coastal Environmental ProcessesYICCASYantai 264003China Yantai Research institute Harbin Engineering UniversityYantai 264006China College of Environmental science and Engineering Guilin University of TechnologyGuilin 541006China

Antibiotic resistance genes(ARGs)might have great effect on ecological security and human *** are important reservoirs that receive tremendous amounts of pollutants ***,information on the proliferation of ARGs in seawater is still *** study performed field sampling to investigate the occurrence and distribution of ARGs in seawater of the South china Sea,which is the deepest and largest sea in *** results showed that the total absolute abundances of ARGs in seawater samples ranged from 2.1.1.^(3)to 2.3×1.^(4)copies/mL,with an of 5.0×1.^(3)copies/mL and a range of 2.2.1.^(3)–1.8×1.^(4)copies/mL for those with mobile genetic elements(MGEs).Genes resistant to multidrug,aminoglycoside,tetracycline,and fluoroquinolone antibiotics accounted for 77.3%–88.6%of total ARGs in *** and Cyanobacteria represented 32.1.–56.{1. 30.4%–49.5%of microbial community,***_MIT931. and Clade_la were the prevalent genera in seawater of the South china *** co-occurrence relationship existed among ARGs,MGEs,and *** activities had critical influence on ARGs and *** wastewater,wastewater treatment plant effluent,sewage,aquaculture tailwater,and runoff were determined as the important sources of ARGs in seawater of the South china Sea based on positive matrix factorization analysis.

关键词： The South china Sea Antibiotic resistance genes Mobile genetic element Source apportionment

Primary migration and secondary alteration of the Upper Paleozoic gas reservoir in Ordos Basin,china―Application of fluid inclusion gases

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science{1. Earth sciences 2008年第S1期51卷 165-173页

作者： GONG Se 1.2.,PENG PingAn 1.,SHUAI YanHua 3 ,DAI JinXing 3 &{2. WenZheng 4 1.{1. institute of Geochemistry,the chinese academy of sciences,{1. 51064.,china 2.Common Wealth Scientific and Research Organization,Petroleum Resources,PO Box 1.6,North Ryde,New South Wales,1.70,Australia 3 Research institute of Petroleum Exploration and Development,Petrochina,Beijing 1.0083,china 4 Research institute of Exploration and Development,Changqing Petroleum Corporation,Xi’an 71.02.0}china guangzhou {1. of Geochemistry the Chinese Academy of Sciences Guangzhou 510640 China Common Wealth Scientific and Research Organization Petroleum Resources PO Box 136 North Ryde New South Wales 1670 Australia Research institute

The composition of fluid inclusions(FI)often represents the initial geochemical characteristics of palaeo-fluid in reservoir *** on composition and carbon isotopic composition of gas during primary migration,reservoir-forming and subsequent secondary alterations are discussed through comparing fluid inclusion gas with coal-formed gas and natural gas in present gas reservoirs in the Ordos *** results show that primary migration of gas has significant effect on the molecular but not on the carbon isotopic composition of *** and diffusion fractionation took place during the secondary migration of gas in Upper Paleozoic gas reservoir according to carbon isotopic composition of methane in *** and carbon isotopic composition of natural gas were nearly unchanged after the gas reservoir forming through comparing the FI gases with the natural gas in present gas reservoir.

关键词： secondary alteration fluid inclusion carbon isotope Ordos Basin

Adsorption of Environmental Pollutants on Pillared Montmorillonite

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Pedosphere 2001年第2期11卷 159-166页

作者： WUPINGxiaL GUOJIUGAO 等 DepartmentofEnvironmentalscienceandEngineering SouthChinaUniversityofTechnologyGuangzhou510640（China） guangzhou{1.ofGeochemistry theChineseAcademyofSciencesGuangzhou510640（

Both inorganic and organic pillared montmorillonites were used to adsorb phenol. Batch kinetics and isotherm studies were carried out to evaluate the effect of equilibrium time and pH on adsorption of phe- nol by montmorillonites and re-adsorbing characteristics of pillared montmorillonites. The adsorption of phenol increased with increasing solution pH values. The elimination ratio of phenol from the solution by the absorption of organic modified pillared montmorillonite (OrPMt) reached equilibrium quickly after vibrating for 5 minutes. Meanwhile for organic montmorillonite (OrMt), pillared montmorillonite (PMt) and montmorillonite (Mt), the time to reach phenol-absorption equilibrium were 2., 30 and 90 minutes, respectively. The adsorbing capacity of the pillared montmorillonite modified with surfactant improved greatly. The phenol-adsorbing capacity of pillared molltmorillonites mainly depended on microporous structure and surface component of the modified clays. After calcination at 500 ℃, the pillar structure and the basal spacing (1.83 um) were still stable. So the pillared montmorillonite could be recycled, and it was a potential material for adsorbing environmental pollutants.

关键词： adsorption phenol pillared montmorillonite