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Integrating the ecosystem service in sustainable plateau spatial planning:A case study of the Yarlung Zangbo River Basin

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Journal of Geographical Sciences 2021年第2期31卷 281-297页

作者： che lei ZHOU Liang XU Jiangang School of Architecture and Urban Planning Nanjing UniversityNanjing 210093China Faculty of Geomatics Lanzhou Jiaotong UniversityLanzhou 730070China Institute of Geographic Sciences and Natural Resources Research CASBeijing 100101China

The Yarlung Zangbo River Basin(YZRB)is a key ecological protection area on the Qinghai-Tibet Plateau(QTP).Determination of the ecosystem service values(ESVs)can help recognize the benefits of sustainable *** is gradually becoming the main path that constructs plateau spatial planning of integrating ecological protection,and achieves global sustainable development goals(SDGs)in *** this paper,the spatio-temporal dynamic evolutions of the ESVs were estimated on the multiple scales of“basin,subbasin and watershed”from 1980 to *** main factors influencing ESVs were explored in terms of physical geography,human activities,and climate *** had been proposed that sustainable spatial planning including ecological protection,basin management,and regional development was urgent to set *** results show that the increase in wetland and forest and results in an increase of 9.4%in the *** should be paid to the reduction of water and *** conservation(WC),waste treatment(WT),and soil formation and conservation(SFC)are the most important ecosystem services in the *** present,the primary problem is to solve the ESVs decreasing caused by glacier melting,grassland degradation,and desertification in the upper reaches *** middle reaches should raise the level of supply *** services should be increased in the lower reaches region on the premise of protecting *** ESVs in adjacent watersheds are interrelated and the phenomenon of“high agglomeration and low agglomeration”is obvious,existing hot-spots and cold-spots of ***,when the altitude is 4500-5500 m,the temperature is 3-8°C,and the annual precipitation is 350-650 mm,ESVs could reach its maximum.A framework of sustainable plateau spatial planning could provide references to delimit the ecological protection red line,key ecological function zone,and natural resource asset accounting on the QTP.

关键词： ecosystem service values spatial planning ecological protection Yarlung Zangbo River Basin Qinghai-Tibet Plateau

Spatio-temporal Dynamic Simulation of Land use and Ecological Risk in the Yangtze River Delta Urban Agglomeration,China

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Chinese Geographical Science 2021年第5期31卷 829-847页

作者： WANG Xiao che lei ZHOU Liang XU Jiangang School of Architecture and Urban Planning Nanjing UniversityNanjing 210093China Faculty of Geomatics Lanzhou Jiaotong UniversityLanzhou 730070China Institute of Geographic Sciences and Natural Resourcs Research.Chinese Academy of Ssciences Beijing 100101China

Rapid urbanization leads to dramatic changes in land use patterns,and the land use/cover change(LUCC)can reflect the spatial impact of urbanization on the ecological *** the process of LUCC and predicting the ecological risk future changes can provide supports for urban ecological *** the Yangtze River Delta Urban Agglomeration(YRDUA),China as the study area,four developmental scenarios were set on the basis of the land use data from 2005 to *** temporal land use changes were predicted by the integration of the system dynamic and the future land use simulation(SD-FLUS)model,and the geographically weighted regression(GWR)model was used to identify the spatial heterogeneity and evolution characteristics between ecological risk index(ERI)and socio-economic driving *** showed that:1)From 2005 to 2015,the expansion of construction land(7670.24 km^(2))mainly came from the occupation of cultivated land(7854.22 km2).The Kappa coefficient of the SD-FLUS model was 0.886,indicating that this model could be used to predict the future land use changes in the YRDUA.2)Gross domestic production(GDP)and population density(POP)showed a positive effect on the ERI,and the impact of POP exceeded that of *** ERI showed the characteristics of zonal diffusion and a slight upward trend,and the high ecological risk region increased by 6.09%,with the largest increase.3)Under different developmental scenarios,the land use and ecological risk patterns *** construction land is increased by 5.76%,7.41%,5.25%and 6.06%,*** the high ecological risk region accounted for 12.71%,15.06%,11.89%,and 12.94%,*** Scenario D,the structure of land use and ecological risk pattern was better compared with other scenarios considering the needs of rapid economic and ecological *** study is helpful to understand the spatio-temporal pattern and demand of land use types,grasp the ecological security pattern of large-sc

关键词： urbanization ecological risk scenario simulation geographically weighted regression(GWR) spatial planning

Effect of Microstructure of Cementite on Interphase Stress State in Carbon Steel

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Journal of Iron and Steel Research International 2007年第4期14卷 31-38页

作者： che lei GOTOH Masahide HORIMOTO Yoshiaki HIROSE Yukio Graduate School Kanazawa University Kanazawa 920-1192 Japan Department of Materials Science and Engineering Kanazawa University Kanazawa 920-1192 Japan

The experiments related to stress states of ferrite and cementite in carbon steels were carried out including in situ four-point bending and tensile test by X-ray diffraction technique. Stresses in the cementite phase can be measured by conventional X-ray diffraction instrument after a specific treatment on the specimen surface. In order to estimate the stress states in two phases, the X-ray elastic constants of two phases in single-phase state （PXEC） are determined by the experimental X-ray elastic constants of them in composite state （CXEC）. The effects of volume fraction and particle size of spheroidal cementite on the interphase stress state are estimated. The experimental results are in good agreement with the theoretical relationships reported in the previous studies.

关键词： multi-phase material surface treatment plastic deformation residual stress X-ray diffraction

Spatio-temporal evolution and influencing factors of urban green development efficiency in China

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Journal of Geographical Sciences 2020年第5期30卷 724-742页

作者： ZHOU Liang ZHOU chenghu che lei WANG Bao Faculty of Geomatics Lanzhou Jiaotong UniversityLanzhou 730070China State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China School of Architecture and Urban Planning Nanjing UniversityNanjing 210093China Northwest Institute of Eco-Environment and Resources CASLanzhou 730000China

To resolve conflicts between development and the preservation of the natural environment,enable economic transformation,and achieve the global sustainable development goals(SDGs),green development(GD)is gradually becoming a major strategy in the construction of an ecological civilization and the ideal of building a"beautiful China",alongside the transformation and reconstruction of the global *** on a combination of the concept and implications of GD,we first used the Slacks Based Model with undesirable outputs(SBM-Undesirable),the Theil index,and the spatial Markov chain to measure the spatial patterns,regional differences,and spatio-temporal evolution of urban green development efficiency(UGDE)in China from 2005 to ***,by coupling natural and human factors,the mechanism influencing UGDE was quantitatively investigated under the framework of the human-environment *** results showed that:(1)from 2005 to 2015,the UGDE increased from 0.475 to 0.523,i.e.,an overall increase of 10%.In terms of temporal variation,there was a staged increase,with its evolution having the characteristics of a"W-shaped"pattern.(2)The regional differences in UGDE followed a pattern of eastern>central>*** different types of urban agglomeration,the UGDE had inverted pyramid cluster growth characteristics that followed a pattern of"national level>regional level>local level",forming a stable hierarchical scale structure of"super cities>mega cities>big cities>medium cities>small cities".(3)UGDE in China has developed with significant spatial agglomeration ***-efficiency type cities have positive spillover effects,while low-efficiency cities have negative *** types of urban evolution processes have a path dependence,and a spatial club convergence phenomenon exists,in which areas with high UGDE are concentrated and drive low UGDE elsewhere.(4)Under the framework of regional human-environment interaction,the degree of human and soc

关键词： green development efficiency green city green economy spatial scale sustainable development goals(SDGs)

Sintering behavior of aluminum nitride powder prepared by self-propagating high-temperature synthesis method

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Rare Metals 2018年第12期37卷 1091-1095页

作者： Liang Qiao Shu-Wen chen Li-Qiang Jiang Kazuo Shinozaki Sheng-lei che Research Center of Magnetic and Electronic Materials College of Materials Science and Engineering Zhejiang University of Technology Department of Metallurgy and Ceramics Science Tokyo Institute of Technology

Fully dense aluminum nitride(AIN) ceramics were synthesized by self-propagating high-temperature synthesis(SHS) method using AIN powder as raw material with Y2O3additive. The sintering behavior was studied at different sintering temperatures and additive contents. The change of phase compositions, secondary phase distributions and grain morphologies during sintering process were investigated. It is shown that fully dense ceramics using AIN powder prepared by SHS method can be obtained when the sintering temperature is above 1830 ℃. Both Y2O3content and sintering temperature have an important influence on the formation of Y-Al-O phase and grain shape. When Y2O3content is identified, the grain morphology converts from polyhedron into sphere-like shape with the rise of sintering temperature. At a certain sintering temperature,the grain size decreases with the increase in Y2O3content. The influencing mechanisms of different YAl-O secondary phases and sintering temperatures on the grain size and morphology were also discussed based on the experimental results.

关键词： Self-propagating high-temperature synthesis AlN Secondary phase Liquid-phase sintering

Preparation of Sm_2Fe_(17) alloy by reduction-diffusion process

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Rare Metals 2018年第11期37卷 989-994页

作者： Hai-Bo chen Jing-Wu Zheng Liang Qiao Yao Ying Li-Qiang Jiang Sheng-lei che Research Center of Magnetic and Electronic Materials College of Materials Science and Engineering Zhejiang University of Technology

SmFealloy is the intermediate material for the preparation of SmFeNx(x ≈ 3); thus, the synthesis of pure SmFemother alloy is the key to obtaining highperformance SmFeNx. Reduction-diffusion(R-D) is a cost-effective method. In this study, the R-D process of synthesizing SmFewas analyzed by scanning electron microscopy(SEM), energy-dispersive X-ray spectroscopy(EDX), X-ray diffraction(XRD), and X-ray fluorescence(XRF). Furthermore, the influences of the tightness of compacted reactants, the compensation amount of SmO,and the particle size of Fe on the formation of SmFewere discussed from the aspects of the three raw *** results show that Sm reduced from SmOreacts with Fe particles to form intermetallic compound SmFedirectly in the R-D reaction process of preparing SmFe;the generation of Sm and its migration to the surface of Fe particles control the reaction rate; a proper tightness of compacted reactants is necessary for ensuring the purity of SmFeproduct; pure SmFecan be obtained when the compensation of SmOis 33 % of the stoichiometry; and the sufficiency of the reaction improves with the decrease in the size of Fe powders under the same reaction condition.

关键词： Sm_2Fe_(17) Reduction-diffusion Rare earth Permanent magnet

Effect of acid-associated mechanical pretreatment on the hydrolysis behavior of pine sawdust in subcritical water

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Chinese Journal of chemical Engineering 2023年第6期58卷 195-204页

作者： Wei Yang Yalun Ma Xu Zhang Fan Yang Dong Zhang Shengji Wu Huanghu Peng Zezhou chen lei che College of Engineering Huzhou UniversityHuzhou 313000China School of Science and Engineering Huzhou CollegeHuzhou 313000China College of Materials and Environmental Engineering Hangzhou Dianzi UniversityHangzhou 310018China

The effects of sulfuric acid-associated mechanical pretreatment on the hydrolysis behavior of pine sawdust were investigated in this *** acid could act as an acidic catalyst to depolymerize holocellulose through cleavage of the glycosidic bonds,the dissociation energies of which were supplied by the impact of a ball on pine sawdust,during *** destruction of glycosidic and hydrogen bonds in pine sawdust resulted in a decrease of crystallinity and an increase of water *** sulfuric acid could promote the hydrolysis of holocellulose and its hydrolysis *** also destroyed the chemical linkages between holocellulose and lignin during ball *** cleavage of chemical linkages with holocellulose made lignin more difficult to hydrolyze in subcritical water,and higher activation energy was needed to hydrolyze pretreated pine sawdust at higher reaction *** also led to the formation of glucose char and aromatic-linked polymer char from the hydrolysis products of holocellulose.

关键词： Acid-associated mechanical pretreatment Subcritical water Pine sawdust Hydrolysis behavior Kinetic parameters

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稀疏平衡变分自动编码器的文本特征提取

国防科技大学学报 2022年第1期44卷 169-178页

作者：车蕾北京信息科技大学信息管理学院北京100192

针对文本特征提取方面的高维数据特征区分度较低、基于规则的特征学习的自学习性能差、变分自动编码器存在过度剪枝等问题,提出稀疏平衡变分自动编码器(Sparse Balanced Variational AutoEncoder,SBVAE)的文本特征提取模型。为消除噪声... 详细信息

针对文本特征提取方面的高维数据特征区分度较低、基于规则的特征学习的自学习性能差、变分自动编码器存在过度剪枝等问题,提出稀疏平衡变分自动编码器(Sparse Balanced Variational AutoEncoder,SBVAE)的文本特征提取模型。为消除噪声干扰,提高文本特征提取模型的鲁棒性,在文本特征提取的输入层采用双向降噪处理机制。提出一种稀疏平衡性处理,结合KL(Kullback-leibler)项权重的模拟退火算法以缓解KL散度引发的过度剪枝的影响,强制解码器更充分地利用潜变量。此模型提高了高维数据特征的区分度。从对比分析文本特征提取模型、稀疏性能、稀疏平衡处理对隐藏空间变分下界的影响等方面深入开展实验,验证了该模型具有较好的性能。该模型在复旦数据集和Reuters数据集上的最高准确率相较于主成分分析分别提升了12.36%、8.06%。

关键词：变分自动编码器降噪稀疏平衡过度剪枝

Land Use Change and Its Impact of Ecosystem Service Value in Yarlung Zangbo River Basin in Southern of Qinghai-Tibet Plateau

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Land Use Change and Its Impact of Ecosystem Service Value in...