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Combining Geomatics and Conventional Methods for Monitoring Forest Conditions under Different Governance Arrangements

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Journal of Mountain Science 2006年第4期3卷 325-333页

作者： Ambika p. Gautam p.o. box 13797 Kathmandu Nepal

This study emp.o.ed an innovative meth- odological framework that combines geomatics and conventional survey methods to monitor changes in forest conditions and examine their associations with local forest governance parameters in a mountain watershed covering 153.3 km2 in the middle moun- tains of Nepal. The study involved two spatial scales and analytical steps. First, geomatics techniques were used to map and detect changes in major land cover types in the watershed between 1976 and 2000 and to analyze relationships between forest cover changes and governance arrangements. This was followed by micro-level analysis of the relationships between the biological conditions of selected forests within the watershed and their governance arrangements, using conventional survey methods and analytical tools. The findings show that forest cover in the watershed in- creased by about 15 per cent during the period. The rate of increase in forest cover was highest in areas under a semi-government type of governance ar- rangement, while the community forests were gener- ally better in terms of current biological conditions compared to the semi-government forests. This in- consistency between the findings from the two analy- ses does not allow us to draw any firm conclusions regarding the role of p.o.erty rights in determining forest condition, but it indicates that the outcomes of local forest management initiatives may be more de-pendent on local institutional arrangements regulat- ing forest use and maintenance of forest resources than on the type of p.o.erty rights arrangements. The findings also p.o.ide evidence of the methodological suitability of the research app.o.ch adopted, which may be useful for addressing many other research questions related to forestry and natural resources management, particularly those involving multiple spatial scales.

关键词： Forest monitoring p.o.erty rights research app.o.ch Nepal

VISCoMETRIC STUDY oF poLY(METHYL METHACRYLATE) AND poLYSTYRENE BLENDS IN DIFFERENT SoLVENTS

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Chinese Journal of polymer Science 2003年第1期21卷 15-19页

作者： omar Melad Rajai Baraka Jamil K.J.Salem Hani Hilles Awni El-Khazandar Department of Chemistry AL-Azhar University P.O. Box 1277 GAZA PalestineDepartment of Chemistry AL-Azhar University P.O. Box 1277 GAZA PalestineDepartment of Chemistry AL-Azhar University P.O. Box 1277 GAZA PalestineDepartment of Chemistry AL-Azhar University P.O. Box 1277 GAZA PalestineDepartment of Chemistry AL-Azhar University P.O. Box 1277 GAZA Palestine

The intermolecular interaction between poly(methyl methacrylate) (pMMA) and polystyrene (pS) intetrahydrofuran (THF) and N,N'-dimethyl formamide (DMF) solvents was studied at 28℃ using a dilute solution viscometrymethod. Solvent is believed to play a key role in characterizing the viscosity behavior of the polymer solution. The intrinsicviscosity and viscosity interaction parameter were experimentally measured for the binary (solvent/polymer) and for theternary systems in two solvents. The compatibility of the polymer mixture was discussed in terms of the sign of △b_m. Theresults show that the compatibility of pMMA/pS blend in DMF is larger than that in THF.

关键词： Viscometry Compatibility pMMA/pS blend

parasitic plant in natural Boswellia papyrifera stands at Humera, Northern Ethiopia

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Journal of Forestry Research 2014年第4期25卷 923-928页

作者： Abraham Yirgu Alemu Gezahgne Habtemariam Kassa Minilik Tsega Forestry Research Centre P.O. BOX 30708 Addis Ababa Ethiopia Centers for International Forestry Research P.O. BOX 5689 Addis Ababa Ethiopia Ethiopian Institute of Agricultural Research P.O. BOX 2003 Addis Ababa Ethiopia

In Boswellia papyrifera （Del.） Hochst natural stands, we stud- ied the association of parasitic plants with B. papyrifera trees from which frankincense was tapped and marketed for domestic and export markets. Data on the rate of infection of parasitic plants on B. papyrifera was collected in three transects located at separate locations around Baha kar, northern Ethiopia. Each transect had ten circular sample p.o.s of 400 m2 and separated by 100 m. Species composition, DBH, height, crown di- ameter, number of main, secondary and tertiary branches and number of parasitic plants on individual trees were recorded. Sixteen tree species were recorded in the combined sample p.o.s. The parasitic plant associ- ated with B. papyrifera was identified as Tapinanthus globiferus. This parasite infected 38% of Boswellia trees in sample p.o.s. The infection rate of the parasitic plant varied from 1 to 33 per Boswellia tree. The infection of T. globiferus on B. papyrifera was predominantly limited to tertiary small branchlets arising from secondary branches; parasitic plants were absent on thick main and secondary branches. In all p.o.s, infectionof T. globiferus was exclusively limited to Boswellia trees. The influence of T. globiferus parasitism on growth of Boswellia trees and its influence on yield of incense p.o.uction needs further investigation. Management of natural stands for frankincense p.o.uction should include measures to reduce infection by T. globiferus.

关键词： Boswellia papyrifera parasitic plant Tapinanthus globiferus Humera Ethiopia

Regular Splitting and potential Reduction Method for Solving Quadratic p.o.ramming p.o.lem with box Constraints

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Journal of Computational Mathematics 2002年第6期20卷 643-652页

作者： Zi-Luan Wei(Institute of Computational Mathematics and Scientific / Engineering Computing, Academy of Mathematics and System Sciences, Chinese Academy of Sciences, p.o. box 2719, Beijing, 100080) Institute of Computational Mathematics and Scientific / Engineering Computing Academy of Mathematics and System Sciences Chinese Academy of Sciences P.O. Box 2719 北京 100080

presents a regular splitting and potential reduction method for solving a quadratic p.o.ramming p.o.lem with box constraints. Discussion on the regular splitting and potential reduction algorithm; Complexity analysis ... 详细信息

关键词： quadratic p.o.ramming p.o.lem regular splitting potential reduction algorithm complexity analysis

Study on the Effects of End-bend Cantilevered Stator in a 2-stage Axial Compressor

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Journal of Thermal Science 2009年第2期18卷 119-125页

作者： Songtao WANG Xin DU Zhongqi WANG Harbin Institute of Technology, p.o. box 458, Harbin 150001, China Harbin Institute of Technology P.O. BOX 458 Harbin 150001 China

Leading edge recambering is applied to the cantilevered stator vanes in a 2-stage compressor in this paper. Differentcurving effects are p.o.uced when the end-bend stator vanes are stacked in different ways. Stacking on theleading edge induces a positive curving effect near the *** it is stacked on the centre of gravity, a negativecurving effect takes place. The numerical investigation shows that the flow field is redistributed when theend-bend stators with leading edge stacking are applied. The variations in the stage matching for the mainstreamand near the hub have an impact on the performance of the 2-stage compressor. The isentropic efficiency and thetotal pressure ratio of the compressor are increased near the design condition. The compressor total pressure ratiois decreased near choke and near stall. The maximum flow rate is reduced and the stall margin is decreased.

关键词： axial compressor end-bend blade stacking stage matching

Exact solution of plane isolated crack normal to a bimaterial interface of infinite extent

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Acta Mechanica Sinica 2006年第5期22卷 455-468页

作者： Tianhu Hao China Textile University P.O. Box 220 Shanghai 200051 China

This paper presents an exact solution for the transverse interface crack in the plane strain case. The crack is perpendicular to the interface and in one material. The exact complex stress functions are first obtained with some unknown constants. The satisfactions of all boundary conditions are then checked, the condition at infinity is considered and the unknown constants are determined. Further study may focus on the case with different shear moduli and the influence of the large deformation.

关键词： Exact solution Interface crack plane strain p.o.lem

pulsed-Laser Annealing of NiTi Shape Memory Alloy Thin Film

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Journal of Materials Science & Technology 2009年第1期25卷 135-140页

作者： S.K. Sadrnezhaad E. Rezvani S. Sanjabi A.A. Ziaei Moayed Materials and Energy Research Center P.O. Box 14155-4777 Tehran Iran Department of Materials Science and Engineering Sharif University of Technology P.O. Box 1156-9466 Tehran Iran Department of Materials Science and Engineering Tarbiat Modarres University P.O. Box 14115-143 Tehran Iran

Local annealing of amorp.o.s NiTi thin films was performed by using an Nd：YAG 1064 nm wavelength pulsed laser beam. Raw samples p.o.uced by simultaneous sputter deposition from elemental Ni and Ti targets onto unheated Si （100） and Silica （111） substrates were used for annealing. Delicate treatment with 15.92 W/mm^2 power density resulted in crystallization of small spots; while 16.52 and 17.51 W/mm^2 power densities caused ablation of the amorp.o.s layer. optical microscopy, scanning electron microscopy, X-ray diffraction and atomic force microscopy were performed to characterize the microstructure and surface morp.o.ogy of the amorp.o.s/crystallized spot patterns.

关键词： Local heat treatment NiTi thin film pulsed laser annealing Amorp.o.s/crystallized spot composite

Low-temperature electrochemical synthesis and characterization of ultrafine Y(oH)_3 and Y_2o_3 nanoparticles

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Journal of Rare Earths 2012年第3期30卷 236-240页

作者： Mustafa AGHAZADEH Taher YoUSEFI Mehdi GHAEMI Laser and optic Research School NSTRI P.O. Box 11365-8486 Tehran Iran Material Research School NSTRI P.O. Box 14395-836 Tehran Iran Department of Chemistry Science Faculty Golestan University P.O. Box 49138-15739 Gorgan Iran

Ultrafine Y（oH）3 nanoparticles were successfully deposited from an additive-free 0.005 mol/L YCl3 low-temperature bath on the steel cathode at the current density of 0.5 mA/cm2 and bath temperature of 10 oC. Heat treatment of the prepared Y（oH）3 nanoparticles at 600 oC in air led to the formation of Y2o3 nanoparticles. Thermal behavior and phase transformation during the heat treatment of Y（oH）3 were investigated by differential scanning calorimetry （DSC） and thermogramimetric analysis （TGA）. The morp.o.ogies, crystal structures and compositions of the prepared materials were examined by means of scanning and transmission electron microscopy （SEM and TEM） as well as X-ray diffraction （XRD） and FT-IR spectroscopy. The results showed that the prepared Y（oH）3 nanoparticles was essentially amorp.o.s and composed of well dispersed ultrafine particles with size of 4 nm. After heat treatment, the obtained oxide p.o.uct was well crystallized cubic phase of Y2o3 nanoparticles with the grain size of around 5 nm. It was concluded that low-temperature cathodic electrodeposition offered a facile and feasible way for preparation of ultrafine Y（oH）3 and Y2o3 nanoparticles.

关键词： Y(oH)3 Y2o3 cathodic electrodeposition heat treatment nanoparticles rare earths

Comparative analysis of Solanum stoloniferum responses to p.o.ing by the green peach aphid Myzus persicae and the potato aphid Macrosiphum eup.o.biae

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Insect Science 2013年第2期20卷 207-227页

作者： Adriana E. Alvarez Viviana G. Broglia Anahi M. Alberti D'Amato Doret Wouters Edwin van der Vossen Elisa Garzo W. Fred Tjallingii Marcel Dicke Ben Vosman Laboratory of Entomology Wageningen University P.O. Box 8031 6700 EH 2Plant Breeding Wageningen UR P.O. Box 386 6700 AAWageningen The Netherlands plant Breeding Wageningen UR P.O. Box 386 6700 AA Wageningen The Netherlands

plants p.o.ect themselves against aphid attacks by species-specific de- fense mechanisms. previously, we have shown that Solanum stoloniferum Schlechtd has resistance factors to Myzus persicae Sulzer （Homoptera： Aphididae） at the epidermal/mesophyll level that are not effective against Macrosiphum eup.o.biae Thomas （Homoptera： Aphididae）. Here, we compare the nymphal mortality, the pre-rep.o.uctive development time, and the p.o.ing behavior of M. persicae and M. eup.o.biae on S. stoloniferum and Solanum tuberosum L. Furthermore, we analyze the changes in gene expression in S. stoloniferum 96 hours post infestation by either aphid species. Although the M. eup.o.biae p.o.ing behavior shows that aphids encounter more p.o.ing constrains on phloem activities-longer p.o.ing and salivation time- on S. stoloniferum than on S. tuberosum, the aphids succeeded in reaching a sustained ingestion of phloem sap.o. both plants. p.o.ing by M. persicae on S. stoloniferum plants resulted in limited feeding only. Survival of M. eup.o.biae and M. persicae was affected on young leaves, but not on senescent leaves of S. stoloniferum. Infestation by M. eup.o.biae changed the expression of more genes than M. persicae did. At the systemic level both aphids elicited a weak response. Infestation orS. stoloniferum plants with a large number ofM. persicae induced morp.o.ogical changes in the leaves, leading to the development of pustules that were caused by disrupted vascular parenchyma and surrounding tissue. In contrast, an infesta- tion by M. eup.o.biae had no morp.o.ogical effects. Both plant species can be regarded as good host for M. eup.o.biae, whereas only S. tuberosum is a good host for M. persicae and S. stoloniferum is not. Infestation ofS. stoloniferum by M. persicae or M. eup.o.biae changed the expression of a set of plant genes specific for each of the aphids as well as a set of common genes.

关键词： cDNA microarrays electrical penetration graph insect-plant interactions,Solanum tuberosum wild potato