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Science china(Technological sciences) 2006年第Z1期49卷 1-8页

作者： TANG Shouzheng, TANG Una, Guofan Shao & DAI Limin Research institute of Resource Information Techniques, chinese academy of Forestry, beijing 100091, china institute of applied Ecology, chinese academy of sciences, Shenyang 110016, china Departmet of Forestry and Natural Resources, Purdue university, West Lafayette, IN 47907, USA graduate university, chinese academy of sciences, beijing 100101, china Research institute of Resource Information Techniques Chinese Academy of Forestry Beijing China institute of applied Ecology Chinese Academy of Sciences Shenyang China graduate university Chinese Academy of Sciences Beijing China Department of Forestry and Natural Resources Purdue University West Lafayette USA

Digital Forestry as a concept was developed after the Digital Earth program. The chinese scientists were not only among the pioneers who first proposed the concept of Digital Forestry, but also contributed a lot to the development of Digital Forestry. Digital Forestry is a digital framework to maintain forest planting, management, using, and protect. The synergetic use of computationally-intensive quantitative methods together with information technologies is the most important foundation for the development of Digital Forestry. Under this situation, the experience of Digital Forestry development in china is relatively rich. A number of academicians, scholars, and professional administrators were involved in discussing the Digital Forestry Construction Scheme. The Project of Digital Forestry Practicability approved by the State Forestry Administration is a major instance in developing Digital Forestry standard and key techniques. By introducing a case study of Digital Forestry, this paper reviews the concept of Digital Forestry, the way turning traditional forestry into Digital Forestry, and the future development of Digital Forestry.

关键词： Digital Forest, Digital Earth, Digital Forestry standard, Digital Forestry techniques.

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Gasdynamic characteristics of toroidal shock and detonation wave converging

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Science china(Physics,Mechanics & Astronomy) 2005年第6期48卷 739-749页

作者： TENG Honghui1,2 & JIANG Zonglin2 1. Key Laboratory of High Temperature Gas Dynamics, institute of Mechanics, chinese academy of Sci- ences, beijing 100080, china 2. graduate university of chinese academy of sciences, beijing 100039, china Key Laboratory of High Temperature Gas Dynamics Institute of Mechanics Chinese Academy of Sciences Beijing China graduate university of chinese academy of sciences Beijing China

The modified CCW relation is applied to analyzing the shock, detonation wave converging and the role of chemical reactions in the process. Results indicate that the shock wave is strengthened faster than the detonation wave in the converging at the same initial Mach number. Euler equations implemented with a detailed chemical reaction model are solved to simulate toroidal shock and detonation wave converging. Gasdynamic characteristics of the converging are investigated, including wave interaction patterns, observable discrepancies and physical phenomena behind them. By comparing wave diffractions, converging processes and pressure evolutions in the focusing area, the different effects of chemical reactions on diffracting and converging processes are discussed and the analytic conclusion is demonstrated through the observation of numerical simulations.

关键词： converging, CCW relation, shock wave, detonation wave.

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Research on Nanometer Technique and Low-Work-Loss Sensor

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稀有金属材料与工程 2006年第S3期 110-112页

作者： Lan Wang~1 Yayan Liu~1 Yifei Yang~(1,2) Jingwen He~1 (1.changchun institute of applied chemistry,chinese academy of sciences,changchun 130022,china) (2.graduate School of chinese academy of sciences,beijing 100080,china)

The preparation process of the CO gas sensor used at normal temperature is *** electric conductance of this type of sensor evolved oscillation from regularly when the sensor is exposed to low level CO *** gas sensing mechanism was investigated by its crystalline *** mechanism of information sensing,which was the concurrence of the grain boundary barrier control and the crystal surface control,is discussed.

关键词： nanometer technique low-work-loss sensor

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Systematic study of the transfer of amino acids across the water/1,2-dichloroethane interface facilitated by dibenzo-18-crown-6

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Science china chemistry 2004年第1期47卷 24-33页

作者： CHEN Yong, YUAN Yi, ZHANG Meiqin, LI Fei, SUN Peng, GAO Zhao & SHAO YuanhuaState Key Laboratory of Electroanalytical chemistry, changchun institute of applied chemistry, chinese academy of sciences, changchun 130022, china College of chemistry and Molecular Engineering, Peking university, beijing 100871, china Lab. of Electroanalytical Chem. Changchun Inst. of Appl. Chem. Chinese Acad. of Sci. Changchun 130022 China Coll. of Chem. and Molecular Eng. Peking Univ. Beijing 100871 China

Facilitated ion transfer reactions of 20 amino acids with dibenzo-18-crown-6 (DB18C6) at the water/1,2-dichloroethane (W/DCE) interfaces supported at the tips of micro- and nano-pipets were investigated systematically using cyclic voltammetry. It was found that there were only 10 amino acids, that is, Leu, Val, lie, Phe, Trp, Met, Ala, Gly, Cys, Gin (in brief), whose protonated forms as cations can give well-defined facilitated ion transfer voltammograms within the potential window, and the reaction pathway was proven to be consistent with the transfer by interfacial complexation/dissociation (TIC/TID) mechanisms. The association constants of DB 18C6 with different amino acids in the DCE (β0), and the kinetic parameters of reaction were evaluated based on the steady-state voltammetry of micro- or nano-pipets, respectively. The experimental results demonstrated that the selectivity of complexation of protonated amino acid by DB18C6 compared with that of alkali metal cations was low, which can be attributed to the vicinal effect arising from steric hindrance introduced by their side group and the steric bulk effect by lipophilic stabilization. Moreover, the association constants and the standard rate constants for different amino acids showed good correlations with their hydrophobicity (π), except Gly and Met, which inferred that the selectivity of such heterogeneous complex reaction for different amino acids with DB18C6, was not only affected by discrimination in binding these ions to the crown ether macro-cycle, but also significantly modified by the ion transfer Gibbs energy which was closely related to the structure of the transferred ions, protonated amino acids.

关键词： micro-/nano-pipet, water/1,2-dichloroethane interface, facilitated ion transfer, cyclic voltammetry, amino acid.

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Evaluation of 10 plant barcodes in Bryophyta (Mosses)

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Journal of Systematics and Evolution 2010年第1期48卷 36-46页

作者： 1,2 Yan LIU 3 Hai-Fei YAN 4 Tong CAO 3 Xue-Jun GE 1(institute of applied Ecology, chinese academy of sciences, Shenyang 110016, china) 2(graduate university of the chinese academy of sciences, beijing 100049, china) 3(Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South china Botanical Garden, chinese academy of sciences, Guangzhou 510650, china) 4(College of Life & Environment sciences, Shanghai Normal university, Shanghai 200234, china) (institute of applied Ecology Chinese Academy of Sciences Shenyang 110016 China) (graduate university of the chinese academy of sciences Beijing 100049 China) (Key Laboratory of Plant Resources Conservation and Sustainable Utilization South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China) (College of Life & Environment sciences Shanghai Normal University Shanghai 200234 China)

DNA barcoding is a molecular tool that uses a standardized DNA region to identify *** preliminary study reported here is the first attempt to specifically focus on universality and attributes of candidate barcodes across a wide systematic range of *** tested eight previously proposed plant barcoding regions(atpF-atpH, ITS2, matK, psbK-psbI, rbcL, rpoB, rpoC1, and trnH-psbA) and two popular phylogenetic markers(rps4 and trnL-trnF of cpDNA) in 49 moss species and 9 liverwort species, representing half of the orders in moss *** ITS2, rbcL, rpoC1, rps4, trnH-psbA and trnL-trnF regions showed good universality, and therefore the efficacy of these loci as DNA barcodes was further evaluated in 36 mosses and 2 liverworts, each of which included two to three individuals per *** five loci, ***, rpoC1, rps4, trnH-psbA and trnL-trnF, were easy to amplify and sequence and showed significant inter-specific genetic variability, making them potentially useful DNA barcodes for *** best performing single loci were the rbcL and rpoC1 coding *** loci showed equivalent performance and combinations of them did not greatly increase their discrimination *** addition, phylogenies generated from each of the separate regions and multi-locus combinations by using best-fit and Kimura 2-parameter models were compared, but no significant difference was found.

关键词： Bryophyta DNA barcoding rbcL rpoC1 rps4 trnH-psbA trnL-trnF.

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Adlayer structure of TCNQ molecules on Cu(111): An in situ STM study

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chinese Science Bulletin 2001年第5期46卷 377-380页

作者： WAN Lijun & Kingo Itayainstitute of chemistry, chinese academy of sciences, beijing 100080, china Department of applied chemistry, graduate School of Engineering, Tohoku university, Sendai, Japan institute of chemistry Chinese Academy of Sciences Beijing China Department of applied chemistry Graduate School of Engineering Tohoku University Sendai Japan

In situ electrochemical scanning tunneling microscopy (STM) was employed to examine tetracyano-quinodimethane (TCNQ) layer adsorbed on Cu(lll) electrode surface in 0.1 mol/L HC1O4 solution. The TCNQ molecules are found to form highly-ordered long range ad-layer with a (4×4) symmetry. Each TCNQ molecule is adsorbed on Cu(111) surface in flat-lying orientation. The molecules are preferentially aligned with their long axes inthe [ 121 ] direction. A structural model is proposed for the adlayer.

关键词： TCNQ molecule electrochemical scanning tunneling microscopy Cu(111) adlayer structure.

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A shortest path algorithm for moving objects in spatial network databases

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Progress in Natural Science:Materials International 2008年第7期18卷 893-899页

作者： Xiaolan Yin a,b,*, Zhiming Ding c, Jing Li a a Technology Center of Software Engineering, institute of Software, chinese academy of Science, P.O. Box 8718, beijing 100080, china b graduate university, chinese academy of sciences, beijing 100049, china c Technology Center of Basic Software, institute of Software, chinese academy of sciences, beijing 100080, china Technology Center of Software Engineering Institute of Software Chinese Academy of Science P.O. Box 8718 Beijing 100080 China graduate university Chinese Academy of Sciences Beijing 100049 China Technology Center of Basic Software Institute of Software Chinese Academy of Sciences Beijing 100080 China

One of the most important kinds of queries in Spatial Network Databases (SNDB) to support location-based services (LBS) is the shortest path query. Given an object in a network, e.g. a location of a car on a road network, and a set of objects of interests, e.g. hotels, gas station, and car, the shortest path query returns the shortest path from the query object to interested objects. The studies of shortest path query have two kinds of ways, online processing and preprocessing. The studies of preprocessing suppose that the interest objects are static. This paper proposes a shortest path algorithm with a set of index structures to support the situation of moving objects. This algorithm can transform a dynamic problem to a static problem. In this paper we focus on road networks. However, our algorithms do not use any domain specific information, and therefore can be applied to any network. This algorithm’s complexity is O(klog2i), and traditional Dijkstra’s complexity is O((i + k)2).

关键词： Moving object Spatial network databases Shortest path index Shortest path

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Thymic epithelial progenitor cells and thymus regeneration: an update

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Cell Research 2007年第1期17卷 50-55页

作者： L ianjun Zhang~(1,2) Liguang Sun~(1,3) Yong Zhao~1 ~1Transplantation Biology Research Division,State Key Laboratory of Biomembrane and Membrane Biotechnology,institute of Zoology,~2graduate university of the chinese academy of sciences,chinese academy of sciences,beijing 100080,china,~3School of Public Health,Jilin university,changchun 130021,china Transplantation Biology Research Division State Key Laboratory of Biomembrane and Membrane Biotechnology Institute of Zoology Chinese Academy of Sciences Beijing China graduate university of the chinese academy of sciences Chinese Academy of Sciences Beijing China School of Public Health Jilin University Changchun China

The thymus provides the essential microenvironment for T-cell development and *** epithelial cells(TECs),which are composed ofthymic cortical epithelial cells (cTECs) and thymic medullary epithelial cells (mTECs),have been well documented to be critical for these tightly regulated *** has long been controversial whether thecommon progenitor cells of TECs could give rise to both cTECs and *** progress has been made to charac-terize the common TEC progenitor cells in recent *** herein discuss the sole origin paradigm with regard to TECdifferentiation as well as these progenitor cells in thymus regeneration.

关键词： thymic epithelial progenitor cells thymus organogenesis thymus regeneration

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A one-dimensional heat transfer model of the Antarctic Ice Sheet and modeling of snow temperatures at Dome A, the summit of Antarctic Plateau

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Science china Earth sciences 2010年第5期53卷 763-772页

作者： CHEN BaiLian1,3, ZHANG RenHe2, SUN ShuFen1, BIAN LinGen2, XIAO CunDe4,2 & ZHANG TingJun5 1 institute of Atmospheric Physics, chinese academy of sciences, beijing 100029, china 2 chinese academy of Meteorological sciences, beijing 100081, china 3 graduate university of chinese academy of sciences, beijing 100049, china 4 Cold and Arid Regions Environmental and Engineering Research institute, chinese academy of sciences, Lanzhou 730000, china 5 The National Snow and Ice Data Center, university of Colorado, Boulder, CO 80309-0449, USA institute of Atmospheric Physics Chinese Academy of Sciences Beijing China graduate university of chinese academy of sciences Beijing China chinese academy of Meteorological sciences Beijing China Cold and Arid Regions Environmental and Engineering Research institute Chinese Academy of Sciences Lanzhou China The National Snow and Ice Data Center University of Colorado Boulder USA

A vertical one-dimensional numerical model for heat transferring within the near-surface snow layer of the Antarctic Ice Sheet was developed based on simplified parameterizations of associated physical processes for the atmosphere, radiation, and snow/ice systems. Using the meteorological data of an automatic weather station (AWS) at Dome A (80°22′S, 70°22′E), we applied the model to simulate the seasonal temperature variation within a depth of 20 m. Comparison of modeled results with observed snow temperatures at 4 measurement depths (0.1, 1, 3, 10 m) shows good agreement and consistent seasonal variations. The model results reveal the vertical temperature structure within the near-surface snow layer and its seasonal variance with more details than those by limited measurements. Analyses on the model outputs of the surface energy fluxes show that: 1) the surface energy balance at Dome A is characterized by the compensation between negative net radiation and the positive sensible fluxes, and 2) the sensible heat is on average transported from the atmosphere to the snow, and has an evident increase in spring. The results are considered well representative for the highest interior Antarctic Plateau.

关键词： Antarctic Ice Sheet near-surface layer energy transfer numerical model

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A photonic crystal side-coupled waveguide based on a high-quality-factor resonator array

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chinese Physics B 2012年第3期21卷 275-282页

作者：崔乃迪梁静秋梁中翥王维彪 State Key Laboratory of applied Optics Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of Sciences graduate university of chinese academy of sciences

Based on the present coupled mode theory of the photonic crystal resonator array in this paper, we propose a novel side-coupled waveguide to achieve highly efficient coupling of photonic crystal devices. It is found that the coupling efficiency is sensitive to the interval, the total number and the quality factor of the resonator. Considering the coupling efficiency and the coupling region, we select five resonators with an interval of six lattice periods. By optimizing the structure parameters of the waveguide and resonator, the quality factors of the resonator can be modulated and the coupling efficiency of the side-coupled waveguide reaches 95.47% in theory. Compared with other coupling methods, the side-coupled waveguide can realize efficient coupling with a compact structure, a high level of integration and a low degree of operational difficulties.

关键词： side-coupled waveguide photonic crystal high-quality-factor cavity

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