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Willingness of Farmer Households for Forest Management and Its Impact Factor Analysis after Collective Forest Tenure Reform

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chinese Forestry science and Technology 2011年第4期10卷 21-35页

作者： Huang Lili Wang Dengju Research institute of Forestry Policy and Information, chinese academy of Forestry, beijing 100091, P. R. china

The study was conducted in Mangling Village under Dehong Perfecture, Yunnan Province, for thorough investigation of forest tenure structure, management mode and forestland transfer of collective forests as well as of farmers' preference for management and transfer intention. The impact factors of management orientation of farmer households were analyzed with Logistic Model. The results showed that tenure structure and management modes of collective forest have been diversified after the collective forest tenure reform, and 87.5% of farmer households preferred to independent or joint management while 12.5% of them would rather to transfer their forestland. The choice of farmer household for management mode was mainly influenced by their education background, production skill, household labors and household income sources. The main factors influencing farmer households' forestland transfer activities include the proportion of forestry revenues to the total revenues, farmers' experiences, amount of household labor and forest land area.

关键词： forest tenure structure management mode forestland transfer willingness for management impact factor

THE DEVELOPMENT OF A MICROCOMPUTER PROGRAM FOR THE THREE-DIMENSIONAL NON-LINEAR FEM

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中国有色金属学会会刊：英文版 1993年第1期3卷 10-15,26页

作者： Ma. Mingjun Liao, Guohua Fang Zulie University of science Technology of beijing, beijing 100083, china

This paper presents a microcomputer program system for the three-dimensional non-linear finite element method (FEM), which is developed for applications in mining engineering, such as excavation, filling, caving, damming, etc. Our attention is focused on some of the key aspects of the programing techniques for an applicable microcomputer program, such as the structure of the program, data processing in the core, communication between the core and mass storage, input and output systems, etc. In the last part of this paper, two test examples are presented verifying the computational accuracy of this programing system and illustrating its applicability in practical engineering.

关键词： Finite Element Method (FEM) Microcomputer Mining Engineering

ORIENTATION VARIANT SELECTION AND ITS EFFECTING FACTORS IN TITANIUM SHEET

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Acta Metallurgica Sinica(English Letters) 1996年第6期9卷 601-605页

作者： Z.S. Zhu N.P.Chen J.L. Gu and M.G. Yan(1)institute of Aeronautical Materials, P.O. Box 8115, beijing 100095, china 2)Department of Materials science and Engineering, Tsinghua University, beijing 100084, ) beijing Inst of Aeronautical Materials Beijing China

By means of crystallite orientation distribution function (ODF) analysis, the influence on orientation variant selection of cold rolling reductions, recrystallization annealing and cooling rates during α→β→α cyclic phase transformation treatments in cold rolled titanium sheet has been investigated. The results show that, cold rolling reduction and annealing treatment both have a great effect on the formation of phase transformation *** variant selection occurs in cold rolled and recrystallization annealed titanium sheet which resulte in a more randomly distributed *** phase transformation texture formed α→β→α transformation is inherited after 3 cycles of α→β→α phase transformation. The cooling rates during phase transformation have little effect on orientation variant selection.

关键词： texture titanium phase transformation orientation variant selection ODF

Crustal thickness and Vp/Vs ratio of the central and western North china Craton and its tectonic implications

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Crustal thickness and Vp/Vs ratio of the central and western...

中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： Zigen Wei,Ling Chen and Weiwei Xu State Key Laboratory of Lithospheric Evolution,institute of Geology and Geophysics,chinese academy of sciences,beijing 100029,china.

SUMMARY We obtained the crustal thickness(H) and average Vp/Vs ratio(κ) for the central(CNCC) and western North china Craton(WNCC) by H-κstacking of receiver *** results show that H andκvaries significantly but similarly in the northern and southern CNCC,reflecting possible effects of the Phanerozoic cratonotic reactivation on the *** the WNCC,the south is featured byκvalues typical for Precambrian shields(～1.77) and variations of H mirroring surface topography;the north presents large fluctuations ofκ(1.68-1.93) and a crustal thickening(up to 50 km) uncorrelated with *** N-S differences were thought to be associated with a～1.95-Ga suturing event occurred in the north with little effects on the *** observations suggest that distinct structural heterogeneities of the NCC not only reflect diverse regional tectonics in Phanerozoic,but also provide evidence for long-term survival of crustal fabrics in stable continental interior.

关键词： Body waves Cratons Crustal structure Asia

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山区花卉的生态旅游价值

山地学报 2008年第S1期26卷 93-96页

作者：马培张丹中国科学院水利部成都山地灾害与环境研究所中国科学院研究生院

作为绿色消费的生态旅游已经迅速普及到全球,我国的生态旅游业也迅速发展起来,但在其开发中面临如何丰富、深化其内涵的问题。针对山区丰富的花卉资源花色斑斓、千姿百态、四季花开不断等特点,对其在发展生态旅游中的造景功能、审美价... 详细信息

作为绿色消费的生态旅游已经迅速普及到全球,我国的生态旅游业也迅速发展起来,但在其开发中面临如何丰富、深化其内涵的问题。针对山区丰富的花卉资源花色斑斓、千姿百态、四季花开不断等特点,对其在发展生态旅游中的造景功能、审美价值、历史文化价值、生态价值以及旅游品牌开发价值等方面进行了讨论。

关键词：花卉山区旅游价值

Endophytic Fungi Associated with Lichen Physcia stellaris Using Different Surface Sterilization Methods

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Endophytic Fungi Associated with Lichen Physcia stellaris Us...

Comparison of the RF MEMS switches with dielectric layers on the bridge’s lower surface and on the transmission line

第八届海峡两岸菌物学学术研讨会

作者： LI Wen-chao~(1,2),GUO Shou-yu~1,GUO Liang-dong~1 (1.Systematic Mycology and Lichenology Laboratory,institute of Microbiology,chinese academy of sciences,beijing 100101 2.Graduate University of chinese academy of sciences,beijing 100049,china)

＜正＞In a survey of endophytic fungi associated with lichen Physcia stellaris in Dongling mountain of beijing, six isolation procedures were evaluated to identify the most suitable one for isolating the internal mycobiota of *** colonization rates（55.4～100%） of fungi were obtained in the six procedures.A total of 28 fungal taxa were recovered from 316 thallus segments of the *** these fungi,one belonged to Ascomycetes,19 to Hyphomycetes,three to Ceolomycetes,one to Mucor,and one to *** surface sterilization procedureⅣ（75%ethanol 1min,2%sodium hypochlorite 3min,75%ethanol 30s）,as a suitable method for lichen endophyte study,was selected,based on the analyses of colonization rates and numbers of endophytic fungi were obtained in the present *** results suggest that there are abundant endophytic fungi within lichen thalli.

关键词： Colonization rate endophyte Physcia stellaris surface sterilization procedure

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science china(Information sciences) 2011年第2期54卷 396-406页

作者： CHEN KenLe & ZHANG JinWen National Key Laboratory of Micro/Nano Fabrication Technology, institute of Microelectronics, Peking University, beijing 100871, china 1. National Key Laboratory of Micro/Nano Fabrication Technology Institute of Microelectronics Peking University Beijing 100871 China

Previously, we proposed that the dielectric layer of RF MEMS switch can be fabricated either on the transmission line, as traditional switches, or on the lower surface of the bridge. This paper presents a detailed comparison of the RF MEMS switches with different positions of dielectric layer. Through theoretically analyzing the physical model of fringing capacitance, it is revealed that different positions of dielectric layer can result in different switch capacitances. Therefore, the change of dielectric-layer position can reduce the switch capacitance and insertion loss when the bridge is much wider than t-line. The theoretical analysis is demonstrated by Maxwell 3D and HFSS simulation, showing that the insertion loss is reduced by around 13% when the bridge width is three times of transmission line width. Further, the inffuence of switch’s structural parameters, such as dielectric material and dimensions of dielectric layer, on the differences between these two kinds of switches is discussed. To achieve high integration together with low-loss and low-actuation-voltage design, the novel switch with dielectric layer on bridge’s lower surface can be expected to have broad applications in the future.

关键词： RF MEMS switch insertion loss fringing capacitance dielectric layer

Evolution of wetting layers in InAs/GaAs quantum-dot system studied by reflectance difference spectroscopy

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Evolution of wetting layers in InAs/GaAs quantum-dot system ...

Crystallization and preliminary X-ray diffraction analysis of FKBP12 complexed with a new neurotrophic ligand

2008 9th International Conference on Solid-State and Integrated-Circuit Technology

作者： Yonghai Chen * Chenguang Tang Bo Xu Peng Jin Zhanguo Wang Key Laboratory of Semiconductor Materials science institute of Semiconductors chinese academy of sciences beijing 100083 P. R. china Key Laboratory of Semiconductor Materials science Institute of SemiconductorsChinese Academy of Sciences

The wetting layers （WL） in InAs/GaAs quantum-dot system have been studied by reflectance difference spectroscopy （RDS）, in which two structures related to the heavy-hole （HH） and light-hole （LH） transitions in the WL have been observed. The evolution and segregation behaviors of WL during Stranski-Krastanow （SK） growth mode have been studied from the analysis of the WL-related optical transition energies. It has been found that the segregation coefficient of Indium atoms varies linearly with the InAs amount in WL. In addition, the effect of the growth temperature on the critical thickness for InAs island formation has also been studied. The critical thickness defined by the appearance of InAs dots, which is determined by AFM, shows a complex variation with the growth temperature. However, the critical thickness determined by RDS is almost constant in the range of 510-540 °C.

关键词： [IEEE Keyword]Quantum dots Strain Atomic measurements Temperature measurement Evolution (biology) Indium Gallium arsenide

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Progress in Natural science:Materials International 2003年第10期 45-47页

作者： LI Pengyun 1, WANG Liwei 1, WU Beili 1, SHU Cuiling 3, NIE Aihua 2, SHEN Beifen, LI Song 2* and RAO Zihe 1*(1. Laboratory of Structural Biology, Department of Biological science and Technology & MOE Laboratory of Protein science, Tsinghua University, beijing 100084, china 2. beijing institute of Pharmacology and Toxicology, Beijng 100850, china 3. beijing institute of Basic Medical science, beijing 100850, china) Laboratory of Structural Biology Department of Biological Science and Technology & MOE Laboratory of Protein Science Tsinghua University Beijing 100084 China beijing institute of Basic Medical science Beijing 100850 China beijing institute of Pharmacology and Toxicology Beijng 100850 China

A novel neurotrophic ligand, (3R) 4 (p toluenesulfonyl) 1,4 thiazane 3 carboxylic acid L phenylalanine ethyl ester, has been complexed with the FK506 binding protein of 12 kD (FKBP12) and crystallized using the hanging drop vapor diffusion method in 0.1 mol/L Hepes Na (pH6.5) solution containing 15%～27% PEG10000. Crystals belong to the P2 1 space group, with unit cell parameters of a =42.0, b =30.4, c =42.4 ?, β =110.7°. The crystals diffract to a 1.8 ? resolution limit.

关键词： FKBP12 (3R) 4 (p toluenesulfonyl) 1 4 thiazane 3 carboxylic acid L phenylalanine ethyl ester complex X ray crystallization ligand neurotrophic.