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Comparing trends of crop and pasture in future land-use scenarios for climate change mitigation

Geography and Sustainability 2024年第3期5卷 470-481页

作者： Maxime Malbranque xiangping hu Francesco Cherubini Industrial Ecology Program Department of Energy and Process EngineeringNorwegian University of Science and TechnologyN-7491TrondheimNorway

Revegetation of former agricultural land is a key option for climate change mitigation and nature *** and abandonment of agricultural land is typically influenced by trends in diets and agricultural inten-sification,which are two key parameters in the Shared Socioeconomic Pathways(SSPs).Datasets mapping future land dynamics under different SSPs and climate change mitigation targets stem from different scenario assump-tions,land data and modelling *** study aims to determine the role that these three factors play in the estimates of the evolution of cropland and pastureland in future SSPs under different climate scenarios from four main datasets largely used in the climate and land surface *** datasets largely agree with the rep-resentation of cropland at present-day conditions,but the identification of pastureland is ambiguous and shows large discrepancies due to the lack of a unique land-use *** occur with future projections,even for the same SSP and climate *** for CO_(2)sequestration from revegetation of abandoned agri-cultural land and CO_(2)emissions from forest clearance due to agricultural expansion shows a net reduction in vegetation carbon stock for most SSPs considered,except ***,different datasets give differences in estimates,even when representative of the same *** SSP1,the cumulative increase in carbon stock until 2050 is 3.3 GtC for one dataset,and more than double for *** study calls for a common classifica-tion system with improved detection of pastureland to harmonize projections and reduce variability of outcomes in environmental studies.

关键词： Natural forest regrowth Scenarios Agriculture Climate change mitigation

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Comparing the climate change mitigation potentials of alternative land uses:Crops for biofuels or biochar *** regrowth

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Geography and Sustainability 2022年第4期3卷 347-357页

作者： Anne Cecilie Løvenskiold xiangping hu Wenwu Zhao Francesco Cherubini Department of Energy and Process Engineering Industrial Ecology ProgrammeNorwegian University of Science and Technology(NTNU)TrondheimNorway State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Institute of Land Surface System and Sustainable Development Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China

Using biomass from dedicated crops for energy production and natural vegetation regrowth are key elements in future climate change mitigation ***,there are still uncertainties about the mitigation potentials that can be achieved by the different land-based systems and how they perform relative to each *** this study,we use harmonized future land use datasets to identify global land areas dedicated to second generation bioenergy crop production in 2050 under different climate *** then assess the global climate change mitigation potentials of using biomass for producing bioethanol with(BECCS)or without carbon capture and storage,biochar,or a synthetic fuel(e-methanol).For the latter,the electricity required to produce hydrogen for e-methanol synthesis is sourced from either wind power or the projected average electricity mix in *** potential from natural regrowth on the identified land is also *** all the cases,we modelled emissions of greenhouse gases from the life-cycle stages and use parameterized models to estimate local biomass growth *** identified land areas range from 1.95 to 13.8 million hectares and can provide from 30 to 178 mega ton(Mt)dry biomass annually from dedicated *** change mitigation potentials range from 11 to 257 MtCO_(2)-***^(−1),depending on technological option and land *** largest mitigation is delivered by BECCS,but e-methanol can achieve similar findings when hydrogen is sourced from wind *** hydrogen is produced from grid electricity,e-methanol can result in net positive emissions.E-methanol can also deliver more final energy than bioethanol(4.04 vs.1.27 EJ yr^(−1)).Natural vegetation regrowth can generally achieve higher mitigation than bioethanol,but less than *** optimal combination of BECCS and natural vegetation regrowth can achieve a larger mitigation,up to 281 MtCO_(2)-***^(−1),indicating that integrated solutions can help to achieve suc

关键词： Negative emission technologies Natural regrowth Land management Bioenergy systems Carbon neutrality

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Coupling trade-offs and supply-demand of ecosystem services(ES):A new opportunity for ES management

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Geography and Sustainability 2021年第4期2卷 275-280页

作者： Qiang Feng Wenwu Zhao Baoling Duan xiangping hu Francesco Cherubini College of Resources and Environment Shanxi University of Finance and EconomicsTaiyuanShanxi 030006China State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Institute of Land Surface System and Sustainable Development Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Industrial Ecology Programme and Department of Energy and Process Engineering Norwegian University of Science and Technology(NTNU)N-7491 NorwegianNorway

The trade-offs and supply-demand relations of ecosystem services(ES)are at the frontier of geographical and ecological ***,previous studies have focused on either trade-offs or the supply-demand aspects,while ES conflicts and supply/demand contradictions have not been comprehensively *** relation-ship between ES trade-offs and supply-demand is logically valid and studying the coupling of both can provide approaches for simultaneously alleviating ES conflicts and supply-demand *** study,based on a review of previous analyses of ES trade-offs and supply-demand dynamics,proposes a new analytic framework to couple ***,we define two types of trade-offs based on the directions of growth or decline of the two *** also define the supply-demand balance area and the supply-demand risk area according to the ES flow ***,the mechanisms driving ES trade-offs are clarified,and land-use scenarios are set based on the ***,the supply-demand spatial characteristics of ES are analyzed,and supply-demand risk areas are ***,scenario iterations are performed to minimize the supply-demand risk area at an acceptable trade-offintensity to identify an optimal land use plan,which simultaneously alleviates ES conflicts and supply-demand *** analytic framework offers new opportunities for improving sustainable ecosystem management.

关键词： Environmental management Service conflicts Supply-demand contradictions Coupling analysis

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Promoting High-quality Digital Transformation and Intelligent Development

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China Oil & Gas 2022年第4期29卷 60-62页

作者： hu xiangping 不详

In recent years,CNPC has firmly grasped the development trend and law of the digital economy,achieved a series of significant achievements in the construction of "Digital CNPC",and given full play to its vital role as an important state-owned backbone enterprise in the new round of scientific and technological revolution and industrial transformation.

关键词： owned CNPC Transformation

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CNPC's New Energy Business Enters the Accelerated Development Stage

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China Oil & Gas 2022年第3期29卷 53-55页

作者： hu xiangping 不详

CNPC adheres to the"dual carbon goals"as its medium and long-term reform and development goals,sets up special operating crews,organizes the preparation of the implementation plan for peak carbon emissions and takes carbon emission reduction measures through industrial structure optimization,energy conservation and efficiency improvement,clean alternatives and carbon capture,utilization and storage(CCUS)according to the actual production conditions.

关键词： CNPC goals measures

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基于分形理论的椭圆弧型指尖密封磨损特性分析

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机械工程学报 2023年第3期59卷 144-157页

作者：雷俊杰刘美红 hu xiangping 王娟王学良昆明理工大学机电工程学院昆明650500 挪威科技大学能源与加工系特隆赫姆N-7491挪威

指尖密封是一种具有广泛应用前景的新型密封技术,其中磨损特性问题属于该技术领域的研究重点。基于分形理论,考虑指尖密封表面与转子表面间的接触关系,将指尖密封与转子的接触系数引入接触点的面积分布表达式,建立了指尖密封磨损分形模... 详细信息

指尖密封是一种具有广泛应用前景的新型密封技术,其中磨损特性问题属于该技术领域的研究重点。基于分形理论,考虑指尖密封表面与转子表面间的接触关系,将指尖密封与转子的接触系数引入接触点的面积分布表达式,建立了指尖密封磨损分形模型,并构建了用于表征磨损能量转化和消耗过程的指尖密封能量密度数学模型;提出了椭圆弧型指尖密封的概念与结构,并与圆弧型、渐开线型指尖密封进行性能对比。计算结果表明接触系数始终小于且逼近于1,两个曲面处处接触,相互包容,接触系数有效;磨损分形模型与经典实验数据对比验证,变化趋势及数量级一致,磨损分形模型可行;存在一个可使体积磨损率最小、能量密度最大的分形维数(D=1.3);随着特征尺寸不断减小,体积磨损率逐渐减小,能量密度逐渐增大;椭圆弧型指尖密封相较于圆弧型、渐开线型指尖密封更适用于高径向跳动量、较高压差和较高转速的密封部位。

关键词：指尖密封分形理论磨损率能量密度椭圆弧型

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Overview of recent land cover changes,forest harvest areas,and soil erosion trends in Nordic countries

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Geography and Sustainability 2021年第3期2卷 163-174页

作者： Na Zhou xiangping hu Ingvild Byskov Jan Sandstad Næss Qiaosheng Wu Wenwu Zhao Francesco Cherubini School of Economics and Management China University of GeosciencesWuhan 430074China Industrial Ecology Program Department of Energy and Process EngineeringNorwegian University of Science and TechnologyN-7491TrondheimNorway State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China

Mapping spatiotemporal land cover changes offers opportunities to better understand trends and drivers of envi-ronmental change and helps to identify more sustainable land management *** study investigates the spatiotemporal patterns of changes in land covers,forest harvest areas and soil erosion rates in Nordic countries,namely Norway,Sweden,Finland,and *** region is highly sensitive to environmental changes,as it is experiencing high levels of human pressure and among the highest rates of global *** analysis that uses consistent land cover dataset to quantify and compares the recent spatiotemporal changes in land cover in the Nordic countries is *** recent products issued by the European Space Agency and the Copernicus Climate Change Service framework provide the possibility to investigate the historical land cover changes from 1992 to 2018 at 300 m *** maps are then integrated with time series of forest harvest areas be-tween 2004 and 2018 to study if and how forest management is represented in land cover products,and with soil erosion data to explore status and recent trends in agricultural *** cover changes typically involved from 4%to 9%of the total area in each *** showed the strongest reduction(11,003 km^(2),−11%of the wetland area in 1992),followed by forest(8,607 km^(2),−1%)and sparse vegetation(5,695 km^(2),−7%),while agriculture(15,884 km^(2),16%)and settlement(3,582 km^(2),84%)showed net *** shrinkage dominated land cover changes in Norway(5,870 km^(2),−18%),followed by forest and grassland with a net gain of 3,441 km^(2)(3%)and 3,435 km^(2)(10%),*** Sweden,forest areas decreased 13,008 km^(2)(−4%),mainly due to agriculture expansion(9,211 km^(2),29%).In Finland,agricultural areas increased by 5,982 km^(2)(24%),and wetland decreased by 6,698 km^(2)(−22%).Settlement had the largest net growth in Denmark(717 km^(2),70%),mainly from conversion of agriculture land.S

关键词： Land cover changes Spatiotemporal analysis Forest management Soil erosion

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Cu催化吲哚啉的炔丙基烷基化/脱氢对映选择性合成手性N-炔丙基吲哚化合物(英文)

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催化学报 2015年第1期36卷 86-92页

作者：朱付林胡向平中国科学院大连化学物理研究所辽宁大连116023 中国科学院大学北京100049

基于吲哚啉的Cu催化不对称炔丙基烷基化及DDQ脱氢策略,成功合成了手性N-炔丙基吲哚化合物.通过使用一个结构刚性的酮亚胺三齿P,N,N-配体,反应获得了很好的对映选择性.该方法反应条件温和、底物适用范围广、产物收率高、立体选择性好,为... 详细信息

基于吲哚啉的Cu催化不对称炔丙基烷基化及DDQ脱氢策略,成功合成了手性N-炔丙基吲哚化合物.通过使用一个结构刚性的酮亚胺三齿P,N,N-配体,反应获得了很好的对映选择性.该方法反应条件温和、底物适用范围广、产物收率高、立体选择性好,为手性N-炔丙基吲哚化合物的合成提供了一条简捷、高效的新途径.

关键词：不对称合成铜炔丙基取代脱氢 N-炔丙基吲哚

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基于近邻图的k-means初始中心选择调优算法

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计算机应用与软件 2014年第4期31卷 178-181,192页

作者：胡湘萍解放军信息工程大学河南郑州450002 河南经贸职业学院河南郑州450018

k-means算法以其算法简单、计算效率高而被广泛应用在数据挖掘、机器学习、计算机视觉等领域。然而,k-means算法的性能严重依赖于其初始聚类中心的选取。不同的初始聚类中心导致k-means算法的聚类结果变化很大。一个合理的方式是选取处... 详细信息

k-means算法以其算法简单、计算效率高而被广泛应用在数据挖掘、机器学习、计算机视觉等领域。然而,k-means算法的性能严重依赖于其初始聚类中心的选取。不同的初始聚类中心导致k-means算法的聚类结果变化很大。一个合理的方式是选取处在数据相对密集区域的数据样本作为初始聚类中心。鉴于此,提出一种基于数据近邻图的k-means初始中心选取算法。该算法分为三个阶段:1)构建数据集的局部近邻图;2)选取初始聚类中心的候选集合;3)确定恰当的初始聚类中心。实验结果表明,该算法选取的初始聚类中心是合理的,同时,可以加快k-means的收敛速度。

关键词：聚类 K均值初始化近邻图

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Chiral Schiff Base Ligands Containing Ferrocene and Pyridine Units for Ruthenium-Catalyzed Asymmetric Transfer Hydrogenation

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催化学报 2003年第8期24卷 565-566页

作者： DAI huicong, hu xiangping, CHEN huilin, BAI Changmin, ZHENG Zhuo (Dalian Institute of Chemical Physics, The Chinese Academy of Sciences, Dalian 116023, Liaoning, China) Dalian Institute of Chemical Physics The Chinese Academy of Sciences 辽宁 Dalian 116023

Chiral Schiff base complexes are very efficient for a wide range of reactions, including expoxidation, epoxide ring opening, Diels-Alder reaction, aldol reaction, etc. However, there are only few examples of P-N chelate Schiff bases being used as the chiral ligands in the asymmetric transfer hydrogenation of ketones. Recently, Gao et al reported a series of P,N,N,P Schiff base ligands that have relatively low ennatioselectivity in the asymmetric transfer hydrogenation of ketones. Here, we report the synthesis of a series of new P,N,N Schiff base ligands 4 (4a, 4b and 4c) and their application in the ruthenium-catalyzed asymmetric transfer hydrogenation. Up to 90% enantiomeric excess (ee) was obtained in the transfer hydrogenation of ethyl phenyl ketone using Ru(DMSO)_4Cl_2/4c as catalyst.

关键词：钌催化剂不对称转移氢化作用手性席夫碱配位化合物二茂铁嘧啶单体

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