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Spatial distribution of soil moisture,salinity and organic matter in Manas River watershed,Xinjiang,China

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Journal of Arid Land 2012年第4期4卷 441-449页

作者： Jilili ABUDUWAILI Yang TANG Mireban ABULIMITI DongWei LIU Long MA State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and Geography Chinese Academy of Sci-ences Urumqi 830011 China College of Resources and Environmental science Xinjiang University Urumqi 830011 China Inner Mongolia University Hohhot 010021 China

With the classical statistical and geostatistical methods, the study of the spatial distribution and its in- fluence factors of soil water, salinity and organic matter was carried out for 0-70 cm soil layers in Manas River watershed. The results showed that the soil moisture data from all soil layers exhibited a normal distribution, with average values of 14.08%-21.55%. Geostatistical analysis revealed that the content of soil moisture had a moder- ate spatial autocorrelation with the ratios of nugget/sill ranging from 0.500 to 0.718, which implies that the spatial pattern of soil moisture is influenced by the combined effects of structural factors and random factors. Remarkable spatial distributions with stripped and mottled features were found for soil moisture in all different soil layers. The landform and crop planting had a relatively big influence on the spatial distribution of soil moisture; total soil salinity was high in east but low in west, and non-salinized soil and lightly salinized soil appeared at the northwest and southwest of the study area. Under the effect of reservoir leakage, the heavily salinized soils are widely distributed in the middle of the study area. The areas of the non-salinized and lightly salinized soils decreased gradually with soil depth increment, which is contrary to the case for saline soils that reached a maximum of 245.67 km2 at the layer of 50-70 cm. The types of soil salinization in Manas River watershed were classified into four classes： the sulfate, chloride-sulfate, sulfate-chloride and chloride. The sulfate salinized soil is most widely distributed in the surface layer. The areas of chloride-sulfate, sulfate-chloride, and chloride salinized soils increased gradually along with the increment of soil depth; the variation range of the average values of soil organic matter content was be- tween 7.48%-11.33%. The ratios of nugget/sill reduced gradually from 0.698 to 0.299 with soil depth increment, which shows that the conten

关键词： soil water and salt organic matter spatial distribution Manas River watershed

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Ripening of SiO2 Particles in Stber’s Process

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Ripening of SiO2 Particles in Stber’s Process

Simulation analysis on characteristics of land surface over western Qinghai-Xizang Plateau during freez-ing-thawing period

中国颗粒学会2002年年会暨海峡两岸颗粒技术研讨会

作者：韦文诚陈婷玮 Dept. Mat. sci. Eng. Taiwan University Taipei 106 Dept. Mat. sci. Eng. Taiwan University Taipei 106

＜正＞ This study has synthesized several submicron monodisperse silica particles by a sol-gel method（modified from Stober’s process）. The reactions undergo the hydrolysis of tetra-ethyl orthosilicate （TEOS） and consolidation in basic conditions. During the reactions, SiO2 particles experienced nucleation and growth in the first stage, then the particles started ripening. The kinetics of size growth in second stage could be well-described by Ostwald ripening, and closed related to synthesis temperature. The relationship of reaction temperature, the effects of catalyst and reactant to the growth phenomena are also reported.

关键词： sol-gel silica ripening mono-size

来源： cnki会议评论

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Research in Cold and Arid Regions 2009年第4期1卷 329-340页

作者： ChengHai Wang,Rui Shi,Yang Cui,HongChao Zuo College of Atmospheric sciences,Lanzhou University.No.222,South Tianshui Road,Lanzhou,Gansu 730000,China. Lanzhou Univ Coll Atmospher Sci 222South Tianshui Rd Lanzhou 730000 Gansu Peoples R China

Using the Global Energy and Water Cycle Experiment-Asian Monsoon-Tibet Plateau Experiment (GAME-Tibet) observa-tional data-from October 2002 through September 2003-of Gaize in the western Qinghai-Xizang Plateau (QXP),the land-surface characteristics of the Qinghai-Xizang Plateau are simulated by the improved land-surface model Common Land Model (CoLM).The results show that CoLM can reproduce the land-surface characteristics of plateau areas *** the sur-face-energy balance of the western QXP in the winter half year,the sensible heat (SH) flux constituted the dominant energy,and the latent heat (LH,here and after) flux is very *** the LH flux nearly equals zero in freezing season,it cannot be ig-nored during the period of freezing-thawing in *** the transition season from midto late-May,the frequent phase change of soil water that is caused by the freezing-thawing process leads to the increase of LH flux and decrease of the Bowen *** simulation results also indicate that the changes of surface effective heat fluxes (SH and LH flux) are associated with precipitation and the frequent change between freezing and thawing processes in soil surface.

关键词： land surface characteristic Qinghai-Xizang Plateau CoLM soil freeze-thaw effective radiation

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Runoff Change of Naoli River in Northeast China in 1955–2009 and Its Influencing Factors

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Chinese Geographical science 2012年第2期22卷 144-153页

作者： SONG Xiaolin LU Xianguo LIU Zhengmao SUN Yonghe Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and Agroecology Chinese Academy of Sci- ences Changchun 130012 China Graduate University of Chinese Academy of sciences Beij＇ing 100049 China Heilongjiang Agricultural Reclamation Survey Design and Research Institute Harbin 150090 China Jiamusi Hydrological Bureau in Heilongjiang Province Jiamusi 154000 China

Runoff change and trend of the Naoli River Basin were studied through the time series analysis using the data from the hydrological and meteorological stations. Time series of hydrological data were from 1957 to 2009 for Bao′an station, from 1955 to 2009 for Baoqing station, from 1956 to 2009 for Caizuizi station and from 1978 to 2009 for Hongqiling station. The influences of climate change and human activities on runoff change were investigated, and the causes of hydrological regime change were revealed. The seasonal runoff distribution of the Naoli River was extremely uneven, and the annual change was great. Overall, the annual runoff showed a significant decreasing trend. The annual runoff of Bao′an, Baoqing, and Caizuizi stations in 2009 decreased by 64.1%, 76.3%, and 84.3%, respectively, compared with their beginning data recorded. The wet and dry years of the Naoli River have changed in the study period. The frequency of wet year occurrence decreased and lasted longer, whereas that of dry year occurrence increased. The frequency of dry year occurrence increased from 25.0%-27.8% to 83.9%-87.5%. The years before the 1970s were mostly wet, whereas those after the 1970s were mostly dry. Precipitation reduction and land use changes contributed to the decrease in annual runoff. Rising temperature and water project construction have also contributed important effects on the runoff change of the Naoli River.

关键词： runoff change hydrological parameters wetland land use human activities Naoli River

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In situ atomic-scale observation of monolayer graphene growth from SiC

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Nano Research 2018年第5期11卷 2809-2820页

作者： Kaihao Yu Wen Zhao Xing Wu Jianing Zhuang Xiaohui Hu Qiubo Zhang Jun Sun Tao Xu Yang Chai Feng Ding Litao Sun SEU-FEI Nano-Pico Center Key Laboratory of MEMS of Ministry of Education School of Electronic Science and Engineering Southeast University Nanjing 210096 China Center for Multidimensional Carbon Materials Institute for Basic Science Ulsan 689-798 Republic of Korea School of Materials science and Engineering Ulsan National Institute of Science and Technology Ulsan 689-798 Republic of Korea institute of Textiles and Clothing The Hong Kong Polytechnic University Hong Kong 999077 China Shanghai Key Laboratory of Multidimensional Information Processing Department of Electrical Engineering East China Normal University Shanghai 200241 China College of Materials science and Engineering Nanjing Tech University Nanjing 210009 China Center for Advanced Carbon Materials Southeast University and Jiangnan Graphene Research Institute Changzhou 213100 China Center for Advanced Materials and Manufacture Joint Research Institute of Southeast University and Monash University Suzhou 215123 China Department of Applied Physics The Hang Kong Polytechnic University Hang Kong 999077 China

Because of its high compatibility with conventional microfabrication processing technology, epitaxial graphene （EG） grown on SiC shows exceptional promise for graphene-based electronics. However, to date, a detailed understanding of the transformation from three-layer SiC to monolayer graphene is still lacking. Here, we demonstrate the direct atomic-scale observation of EG growth on a SiC （11^-00） surface at 1,000℃ by in situ transmission electron microscopy in combination with ab initio molecular dynamics （AIMD） simulations. Our detailed analysis of the growth dynamics of monolayer graphene reveals that three SiC （11^-00） layers decompose successively to form one graphene layer. Sublimation of the first layer causes the formation of carbon clusters containing short chains and hexagonal rings, which can be considered as the nuclei for graphene growth. Decomposition of the second layer results in the appearance of new chains connecting to the as-formed clusters and the formation of a network with large pores. Finally, the carbon atoms released from the third layer lead to the disappearance of the chains and large pores in the network, resulting in a whole graphene layer. Our study presents a clear picture of the epitaxial growth of the monolayer graphene from SiC and provides valuable information for future developments in SiC-derived EG technology.

关键词： graphene epitaxial growth in situ transmissionelectron microscopy

SOLVING NONLINEAR DELAY-DIFFERENTIAL-ALGEBRAIC EQUATIONS WITH SINGULAR PERTURBATION VIA BLOCK BOUNDARY VALUE METHODS

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Journal of Computational Mathematics 2023年第4期41卷 643-662页

作者： Xiaoqiang Yan Xu Qian Hong Zhang Songhe Song Xiujun Cheng College of Liberal Arts and sciences National University of Defense TechnologyChangsha 410073China State Key Laboratory of High Performance computing National University of Defense TechnologyChangsha 410073China College of science Zhejiang Sci-Tech UniversityHangzhou 310018China institute of Natural sciences Shanghai Jiao Tong UniversityShanghai 200240China

Block boundary value methods(BBVMs)are extended in this paper to obtain the numerical solutions of nonlinear delay-differential-algebraic equations with singular perturbation(DDAESP).It is proved that the extended BBVMs in some suitable conditions are globally stable and can obtain a unique exact solution of the ***,whenever the classic Lipschitz conditions are satisfied,the extended BBVMs are preconsistent and pth order ***,through some numerical examples,the correctness of the theoretical results and computational validity of the extended BBVMs is further confirmed.

关键词： Nonlinear delay-diferential-algebraic equations with singular perturbation Block boundary value methods Unique solvability Convergence Global stability

Erratum to: Identification of a novel mutation in a Chinese family with Nance-Horan syndrome by whole exome sequencing

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Journal of Zhejiang University-science B(Biomedicine & Biotechnology) 2014年第11期15卷 1011-1011页

作者： Nan HONG Yan-hua CHEN Chen XIE Bai-sheng XU Hui HUANG Xin LI Yue-qing YANG Ying-ping HUANG Jian-lian DENG Ming QI Yang-shun GU Department of Ophthalmology the First Affiliated HospitalSchool of MedicineZhejiang University Beijing Genomics institute (BGI)-Shenzhen School of basic Medical sciences Zhejiang University Functional Genomics Center Department of Pathology&Laboratory MedicineUniversity of Rochester Medical Center

Erratum to:J Zhejiang Univ-sci B(Biomed&Biotechnol)2014 15(8):727-734doi:10.1631/jzus.B1300321The original version of this article unfortunately contained a *** the authors'Nan HONG§1,Yan-hua CHEN§1,Chen XIE1,Bai-sheng XU1,Hui HUANG2,Xin LI2,Yue-qing YANG2,Ying-ping HUANG2,Jian-lian DENG2,Ming QI2,3,4,Yangshun GU1',the superscript sequence number'1',

关键词： Erratum to Identification of a novel mutation in a Chinese family with Nance-Horan syndrome by whole exome sequencing

Genome-wide identification of WRKY gene family and expression analysis under abiotic stresses in Andrographis paniculata

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BIOCELL 2021年第4期45卷 1107-1119页

作者： QICHAO WANG WUJING ZENG BASHARAT ALI XUEMIN ZHANG LING XU ZONGSUO LIANG Zhejiang Province Key Laboratory of Plant Secondary Metabolism and Regulation College of Life Sciences and MedicineZhejiang Sci-Tech UniversityHangzhou310018China Department of Agronomy University of AgricultureFaisalabad38040Pakistan Tianjin Tasly Modern TCM Resources Co. Ltd.Tianjin300410China

Andrographis paniculata(***)is a Chinese herbal medicine that clears away heat,reduces inflammation,protects the liver,and promotes *** WRKYs of *** are still not well characterized,although many WRKYs have been identified in various plant *** the present study,59 *** WRKY(ApWRKY)genes were identified and renamed on the basis of their respective chromosome *** ApWRKYs were divided into three groups via phylogenetic analysis according to their WRKY domains and combined with WRKY of *** 59 identified ApWRKY transcription factors were nonuniformity distributed on 23 chromosomes of *** the structural analysis of the conserved motifs,different ApWRKYs structures showed different biological functions,and the ApWRKY transcription factor had certain species-specificity in the evolutionary *** expression patterns of the 41 ApWRKYs were examined through quantitative real-time PCR(qRT-PCR)in various tissues and under abiotic stresses(salt).The results showed that most of the ApWRKY had different reactions to salt *** addition,the content of the four main secondary metabolites in *** leaves was determined under salt *** results show that under a low concentration of salt treatment,the synthesis of andrographolide can be improved.

关键词： A.paniculata ApWRKY Secondary metabolites Diterpene lactones Andrographolide Abiotic stress

Teaching Reform and Practice of "Algorithms and Data Structures"

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Teaching Reform and Practice of "Algorithms and Data Structu...