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EXISTENCE OF SOLUTION FOR BOUNDARY VALUE PROBLEM OF NONLINEAR FRACTIONAL DIFFERENTIAL EQUATION

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Applied Mathematics(A Journal of Chinese Universities) 2007年第3期22卷 291-298页

作者： Su xinwei liu Landong Dept. of Math. China University of Mining and Technology Beijing 100083 China

This paper is concerned with the boundary value problem of a nonlinear fractional differential equation. By means of Schauder fixed-point theorem, an existence result of solution is obtained.

关键词： fractional differential equation boundary value problem Caputo's fractional derivative Schauder fixed-point theorem.

A two-stage reduction process for the production of high-purity ultrafine Ni particles in a micro-fluidized bed reactor

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Particuology 2015年第2期13卷 27-34页

作者： Jun Li xinwei liu Li Zhou Qingshan Zhu Hongzhong Li State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of Sciences

A novel two-stage reduction process for synthesis of ultrafine nickel powder with a high purity and low density in a fluidized bed reactor has been developed in this work. The raw ultraflne NiO particles are first pre-reduced using hydrogen at lower temperatures （340-400 ℃）, followed by further reduction at higher temperatures （500-600℃）. The self-agglomeration of Ni particles formed during low-temperature reduction decreases the sintering activity of the newly formed ultrafine Ni particles, leading to good fluidization quality, even for the subsequent high-temperature reduction process. The agglomerated Ni particles have a high Ni content （above 99wt%）, a low density （0.78g/cm^3） and a uniform particle size （approximately 100 μm）. A concept design for a novel two-stage fluidized bed reactor process used to produce high-purity Ni powder was also proposed. This approach may be extended to the synthesis of other ultrafine/nanosized metals or metal oxides through a fluidization method.

关键词： Ultrafine Ni powder Production Fluidized bed reactor Two-stage reduction

Reductive Cleavage of C-O Bond in Model Compounds of Lignin

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Chinese Journal of Chemistry 2017年第6期35卷 938-942页

作者： Huanjun Xu xinwei liu Yanfei Zhao Cailing Wu Yu Chen Xiang Gao Zhimin liu Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Colloid lnterjace and Chemical Thermodynamics Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China

A simple protocol for reductive cleavage of C--O bond in diaryl and aryl methyl ethers was reported, in which Nail served as a reducing agent and KO Bu as a base and a radical initiator. The combination of Nail and KOBu displayed high efficiency for reductive cleavage of C-O bond in diaryl and awl ethers （e.g., dibenzofuran, diphe- nyl ether, anisole） without the hydrogenation of the aryl rings, in the absence of any other catalysts or ligands at 140 ℃, producing corresponding arenes and phenols. It was indicated that the reaction was under a radical mecha- nism.

关键词： lignin C-O bond aryl ethers reductive cleavage aromatics

Past, Status Quo and Future of China’s Territorial Planning

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Chinese Journal of Population,Resources and Environment 2008年第4期6卷 28-34页

作者： liu xinwei Wu Chuguo Zhang Qiuming Zhang Lijun Information Center of the Ministry of Land Resources Beijing 100812 China

Since 1949, China has witnessed four development stages of territorial planning. (1) In the 1950s the territorial planning got its start. (2) From the 1960s to 1970s territorial planning declined. (3) From, the 1980s to 1990s the first major tide of territorial planning began. (4) From the end of the 1990s to recent times the new round of territorial planning is under deliberation. Since 1998, the Ministry of Land and Resources has carried out some related work, especially in organizing pilot projects, and early research on the new round of national territorial planning. According to the need for economic and social development and the current conditions in China, it is the appropriate for China to carry out the new round of territorial planning. However, the government should correctly consider the correlations between territorial planning and other plannings, and take appropriate development action, e.g. stressing main points for the basis of overall planning, building a territorial planning system that coordinate with national conditions, strengthening research on various supportive measures of territorial planning, summarizing and upgrading experiences obtained in pilot projects, strengthening international exchange and training talented personnel.

关键词： past status quo future territorial planning China

Iron-bound organic carbon dynamics in peatland profiles:The preservation equivalence of deep and surface soil

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Fundamental Research 2023年第6期3卷 852-860页

作者： Xinya Huang xinwei liu Liangshuai Chen Yanfen Wang Huai Chen Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization&Ecological Restoration Biodiversity Conservation Key Laboratory of Sichuan Province Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041China Zoige Peatland and Global Change Research Station Chinese Academy of SciencesHongyuan 624400China CAS Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of Sciences(CAS)Beijing 100101China. University of Chinese Academy of Sciences Beijing 100049China

More than half of the carbon pools in peatlands are stored in the soil layers below 30 cm,yet little is known about the carbon stabilizing factors at these *** iron oxide minerals are considered to be important for stabilizing organic carbon(OC),their role in the preservation of OC in peatlands,especially in the deep layers,is poorly ***,we collected 1 m soil profiles from six peatlands in Central and West China to quantitatively study the vertical distribution characteristics of iron-bound OC(Fe-bound OC),and the influencing physicochemical properties of the *** results showed that the content of reactive iron(FeR)was enriched in the top layer and decreased gradually with *** Fe-bound OC was positively correlated with FeR,its concentration did not decrease with depth in the peat *** were no obvious trends in the distributions of FeR and Fe-bound OC with water level fluctuations in the peat *** addition,the proportion of Fe-bound OC to soil organic carbon in the deep peat(31 to 100 cm)was equivalent to that in the surface peat(0 to 30 cm),indicating that iron oxide mineral provides comparable protection of OC in both *** to upper estimates of global peatland carbon storage(612 Pg),it could be predicted that 23.81±11.75 Pg of OC is protected by association with *** results indicated that iron oxide minerals are the effective"rusty sink"of OC sequestration in peatland,and a key factor for its long-term *** results from this study make a valuable contribution to the carbon dynamics knowledgebase for peatlands,and provide a basis for improved predictive simulations.

关键词： Iron-bound organic carbon Peatland Soil profile Reactive Fe Carbon preservation

“C-wetland”:A new paradigm to enhance conservation of carbon-rich wetlands

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The Innovation 2023年第2期4卷 13-14页

作者： Huai Chen Zicheng Yu Ning Wu Yanfen Wang xinwei liu Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization&Ecological Restoration Biodiversity Conservation Key Laboratory of Sichuan Province Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041China Zoige Peatland and Global Change Research Station Chinese Academy of SciencesHongyuan 624400China Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains(Ministry of Education) School of Geographical SciencesNortheast Normal UniversityChangchun 130024China State Key Laboratory of Black Soils Conservation and Utilization Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China College of Resources and Environment University of Chinese Academy of SciencesBeijing 101408China State Key Laboratory of Tibetan Plateau Earth System Resources and Environment(TPESRE)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

Wetlands have the highest ecosystem service value among all terrestrial *** their ecosystem services,carbon sequestration and its potential ability to mitigate climate change have been extensively discussed recently,not only in the academic community but in media during COP27 of UNFCCC and COP14 of *** particular,peatlands-peat-accumulating wetlands-accumulate 600 Gt C globally.

关键词： wetlands carbon globally

Mongolia's Prairie Road Strategy Broadens the Prospects for Economic and Trade Cooperation with China

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China's Foreign Trade 2018年第3期 33-35页

作者： liu xinwei

Mongoliais one of the earliest countries to have established diplomatic relations with *** present,Sino-Mongolian relations have gained a previously-unseen *** 2017,***,former Prime Minister of Mongolia,paid a visit

关键词：道路发展贸易合作中国蒙古草原经济外交关系

＂She-Economy＂ Contributes to Global Growth

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China's Foreign Trade 2017年第2期 46-47页

作者： liu xinwei

＂Women have a higher contribution to global economic growth than new technologies,＂ said Song Yueping, an associate professor from the Center for Population and Development Studies of Renmin University of China. ＂

关键词：英语阅读理解对外贸易

China-LatAm Trade Continues Increasing

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China's Foreign Trade 2015年第2期 54-55页

作者： liu xinwei

On January 8,the First Ministerial Meeting of the Forum of China and the Community of Latin America was held in the Great Hall of the People in Beijing,which is China’s first"host diplomacy"in the year of 2015 and which signals the official start of the ChinaLatin America Community forum mechanism and a new era featuring comprehensive China-Latin America collaboration.

关键词： official collaboration featuring Latin jointly companies prosperity ceremony specialized cooperation