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GIS-based Analysis for Hotspot Identification of Tradeoff Between Ecosystem Services： A Case Study in Yanhe Basin, China

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Chinese Geographical Science 2016年第4期26卷 466-477页

作者： ZHENG Zhenmin FU Bojie feng xiaoming State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Joint Center for Global Change Studies Beiiing 100875 China

Although the quantification and valuation of ecosystem services have been studied for a long time, few studies have specifi- cally focused on the quantification of tradeoffs between ecosystem services and tradeoff hotspots, Based on previous studies of ecosys- tem service assessment, we proposed a feasible method to analyze the tradeoffs between ecosystem services, including determination of their relationship, quantification of tradeoffs, and identification of tradeoff hotspots. Potential influencing factors were then further ana- lyzed. The Yanhe Basin in the Loess Plateau was selected as an example to demonstrate the application process. Firstly, the amounts of net primary production （NPP） and water yield （WY） in 2000 and 2008 were estimated by using biophysical models, Secondly, correla- tion analysis was used to indicate the tradeoffs between NPP and WY. Thirdly, tradeoff index （TINpp/wy） was established to quantify the extent of tradeoffs between NPP and WY, and the average value of TINpp/wy is 24.4 g/（mm·m2） for the Yanhe Basin between 2000 and 2008. Finally, the tradeoff hotspots were identified. The results indicated that the area of lowest tradeoff index concentrated in the mid- dle part of the Yanhe Basin and marginal areas of the southern basin. Map overlapping was used for preliminary analysis to seek poten- tial influencing factors, and the results showed that shrub was the best suited for growing in the Yanhe Basin, but also was a potential irtfluencing factor for formulatiort of the tradeoff hotspots. The concept of tradeoff index could also be used to quantify the degree of synergy between different ecosystem services. The method to identify the tradeoff hotspots could help us to narrow the scope of study area for further research on the relationship among ecosystem services and concentrate on the potential factors for formation of tradeoff between ecosystem services, enhance the capacity to maintain the sustainability of ecosystem.

关键词： correlation analysis net primary productivity water yield tradeoff index inlluencing tactor

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A Methodology for Estimating Leaf Area Index by Assimilating Remote Sensing Data into Crop Model Based on Temporal and Spatial Knowledge

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Chinese Geographical Science 2013年第5期23卷 550-561页

作者： ZHU Xiaohua ZHAO Yingshi feng xiaoming Key Laboratory of Quantitative Remote Sensing Information Technology Academy of Opto-ElectronicsChinese Academy of Sciences Institute of Remote Sensing and Digital Earth Chinese Academy of Sciences University of Chinese Academy of Sciences Research Center of Eco-environmental Science Chinese Academy of Sciences

In this paper,a methodology for Leaf Area Index(LAI) estimating was proposed by assimilating remote sensed data into crop model based on temporal and spatial ***,sensitive parameters of crop model were calibrated by Shuffled Complex Evolution method developed at the University of Arizona(SCE-UA) optimization method based on phenological information,which is called temporal *** calibrated crop model will be used as the forecast ***,the Taylor′s mean value theorem was applied to extracting spatial information from the Moderate Resolution Imaging Spectroradiometer(MODIS) multi-scale data,which was used to calibrate the LAI inversion results by A two-layer Canopy Reflectance Model(ACRM) *** calibrated LAI result was used as the observation ***,an Ensemble Kalman Filter(EnKF) was used to assimilate MODIS data into crop *** results showed that the method could significantly improve the estimation accuracy of LAI and the simulated curves of LAI more conform to the crop growth situation closely comparing with MODIS LAI *** root mean square error(RMSE) of LAI calculated by assimilation is 0.9185 which is reduced by 58.7% compared with that by simulation(0.3795),and before and after assimilation the mean error is reduced by 92.6% which is from 0.3563 to *** these experiments indicated that the methodology proposed in this paper is reasonable and accurate for estimating crop LAI.

关键词： assimilation temporal and spatial knowledge Leaf Area Index (LAI) crop model Ensemble Kalman Filter (EnKF)

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Chiral organobases: Properties and applications in asymmetric catalysis

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Chinese Chemical Letters 2018年第8期29卷 1201-1208页

作者： Weidi Cao Xiaohua Liu xiaoming feng Key Laboratory of Green Chemistry & Technology Ministry of Education College of Chemistry Sichuan University

Chiral organobases occupy a significant position in asymmetric organocatalysis. The general types of chiral organobases include tertiary amines, amidines, guanidines, cyclopropenimines, and iminophosphoranes, etc. These organobases are demonstrated to be effective organocatalysts to promote divers kinds of base-initiated reactions in excellent yields and stereoselectivities. In previous reports, several groups have summarized each kind of chiral organobases in different reviews. To the aim of understanding the whole of them in one review, herein, we provide a brief introduction of these chiral organobases in asymmetric catalysis.

关键词： Chiral organobases Asymmetric organocatalysis Amines Amidines Guanidines Cyclopropenimines Iminophosphoranes

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Catalytic asymmetric synthesis of chiral azo compounds via interrupted Japp-Klingemann reaction with aryldiazonium salts

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Science China Chemistry 2022年第3期65卷 546-553页

作者： Yan Wang Aying Yihuo Lifeng Wang Shunxi Dong xiaoming feng Key Laboratory of Green Chemistry&Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengdu 610064China

Asymmetric synthesis of enantioenriched azo compounds bearing tetrasubstituted stereocenter was achieved through chiral N,N′-dioxide/metal Lewis acid promoted interrupted Japp-Klingemann reaction of aryldiazonium tetrafluoroborate salts with nucleophiles under mild conditions. This protocol features wide substrate scope and good functional group ***-containing chiral azo compounds were stable enough in Japp-Klingemann reaction condition. The key to success of the reaction was the employment of metal salt/N,N′-dioxide ligand and the dual-task roles of the base. Moreover, the X-ray crystal structure of Ni(II)/N,N′-dioxide/substrate complex confirmed that the substrate was activated by bidentate coordination, which shed light on the origin of chiral control of the reaction.

关键词： asymmetric synthesis Japp-Klingemann reaction chiral azo compounds aryldiazonium salts N-electrophile

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Asymmetric catalytic 1,3-dipolar cycloaddition ofα-diazoesters for synthesis of 1-pyrazoline-based spirochromanones and beyond

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Science China Chemistry 2021年第8期64卷 1355-1360页

作者： Peng Zhao Zegong Li Jun He Xiaohua Liu xiaoming feng Key Laboratory of Green Chemistry&Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengdu610064China

A highly enantioselective 1,3-dipolar cycloaddition ofα-substituted diazoesters with exocyclic enones was achieved with chiral scandium(III)/N,N’-dioxide complex as the *** protocol provided a facile and efficient route to optically active 1-pyrazoline-based spirochromanones and others with good outcomes(up to 97%yield,98%ee with>95:5 dr).Moreover,enantioenriched 2-pyrazoline-based spirochromanones were also accessible by switchingα-substituted diazoesters toα-*** further specific transformations of chiral pyrazoline-based spiro-compounds to spirocyclopropane derivatives were disclosed as well.

关键词： asymmetric synthesis α-diazoesters 1,3-dipolar cycloaddition exocyclic enone pyrazoline

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Chiral Amino Acids-Derived Catalysts and Ligands

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Chinese Journal of Chemistry 2018年第9期36卷 791-797页

作者： Xiaohua Liu Shunxi Dong Lili Lin xiaoming feng Key Laboratory of Green Chemistry & Technology Ministry of Education College of Chemistry Sichuan University Chengdu Sichuan 610064 China

Transforming amino acids into novel catalysts and ligands is a remarkable subset of new catalyst development in order to imitate enzymatic efficiencies. Their ability to perform a variety of asymmetric catalytic reactions is complimented by their ready availability, rich transformations, stability and easy＇procedure. Herein, we focused-on describing our endeavoT ofdeveloping new catalysts and ligands from primary and secondary amino acids. It includes C2-symmetric N,N＇-dioxides, guanidine-amides, bispidine-based diamines, and other organic salts. The account covered a brief introduction about their discovery, representative applications and related mechanisms.

关键词： chirality asymmetric catalysis amino acids organocatalysts ligands

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Remote Sensing of Ecosystem Services:An Opportunity for Spatially Explicit Assessment

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Chinese Geographical Science 2010年第6期20卷 522-535页

作者： feng xiaoming FU Bojie YANG Xiaojun Lü Yihe State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing100085China Department of Geography Florida State UniversityTallahasseeFlorida 32306USA

Ecosystem service is an emerging concept that grows to be a hot research area in *** explicit ecosystem service values are important for ecosystem service ***,it is difficult to quantify ecosystem *** sensing provides images covering Earth surface,which by nature are spatially ***,remote sensing can be useful for quantitative assessment of ecosystem *** paper reviews spatially explicit ecosystem service studies conducted in ecology and remote sensing in order to find out how remote sensing can be used for ecosystem service *** important areas considered include land cover,biodiversity,and carbon,water and soil related ecosystem *** found that remote sensing can be used for ecosystem service assessment in three different ways:direct monitoring,indirect monitoring,and combined use with ecosystem *** plant and water related ecosystem services can be directly monitored by remote *** commonly,remote sensing can provide surrogate information on plant and soil characteristics in an *** ecosystem process related ecosystem services,remote sensing can help measure spatially explicit *** conclude that acquiring good in-situ measurements and selecting appropriate remote sensor data in terms of resolution are critical for accurate assessment of ecosystem services.

关键词： ecosystem service remote sensing spatially explicit assessment surrogate information

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Multisubstituted pyrazole synthesis via[3+2]cycloaddition/rearrangement/N-H insertion cascade reaction of α-diazoesters and ynones

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Chinese Chemical Letters 2021年第1期32卷 132-135页

作者： Peng Zhao Zi Zeng xiaoming feng Xiaohua Liu Key Laboratory of Green Chemistry&Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengdu 610064China

The cascade reactions of alkyl α-diazoesters and ynones using Al(OTf)_(3) as the catalyst are described.A series of 4-substituted pyrazoles were obtained via [3+2] cycloaddition,1,5-ester shift,1,3-H shift,and N-H insertion *** labelling experiments,kinetic studies and control experiments were carried out for the rationalization of the mechanism.

关键词： Pyrazole Cascade reaction α-Diazoester Ynone Al(OTf)_(3)

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围产期丧失哀伤辅导干预的研究进展

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护理学杂志 2025年第1期40卷 22-26页

作者：刘凯丽雷蕾冯晓明连俊红戴晓婧武汉科技大学医学院护理系湖北武汉430065 中国人民解放军中部战区总医院骨科

从围产期丧失与哀伤辅导的概述、围产期丧失哀伤辅导干预、如何优化围产期丧失哀伤辅导3个方面进行综述,旨在帮助围产期丧失女性以及家庭成员减轻哀伤反应,促进其心理健康,为优化围产期丧失哀伤辅导方案和围产期丧失哀伤辅导的实践提供... 详细信息

从围产期丧失与哀伤辅导的概述、围产期丧失哀伤辅导干预、如何优化围产期丧失哀伤辅导3个方面进行综述,旨在帮助围产期丧失女性以及家庭成员减轻哀伤反应,促进其心理健康,为优化围产期丧失哀伤辅导方案和围产期丧失哀伤辅导的实践提供参考。

关键词：围产期丧失哀伤哀伤辅导丧亲护理悲伤心理健康社会支持综述文献

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C–H alkylation of pyridines with olefins catalyzed by imidazolin-2-iminato-ligated rare-earth alkyl complexes

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Science China Chemistry 2023年第6期66卷 1804-1813页

作者： Dawei Li Lichao Ning Qiliang Luo Shiyu Wang xiaoming feng Shunxi Dong Key Laboratory of Green Chemistry&Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengdu 610064China

An array of rare-earth bis(aminobenzyl)complexes supported by imidazolin-2-iminato ligands were synthesized and structurally *** complexes showed high activity towards ortho-Csp^(2)–H alkylation of 2-alkylpyridines and benzylic Csp^(3)–H alkylation of 2,6-dialkylpyridines with alkenes.A wide range of alkyl or aryl substituted olefin substrates are compatible,providing an atom-economical route to linear or branched alkylated pyridine derivatives in moderate to high yields(45 examples,up to 99%yield).The primary study suggested that the asymmetric version of Csp^(3)–H alkylation of 2,4,6-collidine with allylbenzene was feasible with chiral imidazolin-2-iminato-ligated scandium(III)complexes,and good yield with moderate enantioselectivity was obtained(84%yield,84:16 er).Mechanistic investigations including kinetic isotope effect(KIE)experiments and density functional theory(DFT)calculations shed light on the catalytic cycle and the origin of enantiocontrol.

关键词： pyridine C-H functionalization rare-earth imidazolin-2-iminato ligand asymmetric catalysis

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