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Using remote sensing to assess impacts of land management policies in the Ordos rangelands in China

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International Journal of Digital Earth 2013年第S02期6卷 81-102页

作者： weicheng wu Eddy De Pauw Claudio Zucca International Center for Agricultural Research in Dry Areas(ICARDA)/CGIAR AmmanJordan Pedology and Land Degradation Department of Agriculture and Desertification Research Group(NRD)University of Sassari07100 SassariItaly

Implementation of land management policies influences land use and hence causes environmental *** the Ordos rangelands in China as a case study,this paper explores the potential of remote sensing to assess in dryland areas the impacts of policies on the *** Landsat images of the period 19782010 were acquired and those corresponding to the starting dates of implementation of different policies were selected for land-cover change analysis;others were used to check the detected change and track the normalized difference vegetation index(NDVI)trajectory matched with time series of meteorological data for calibration of natural response of rangelands to *** results indicate that policy impacts are complex and include both positive and negative aspects depending on the locality in *** one hand,policies have aroused the enthusiasm of people in agricultural production and sandcontrol leading to the recovery of about 2618 km2 of desertified rangeland and sandy land,and economic growth,on the other hand,provoked vegetation degradation with an accumulated area of 2439 km2 when policies cannot reconcile the conflict between environmental protection and the interest of rural ***,degradation is not absolute and can be mitigated by the implementation of rational policies.

关键词： land use/cover change multi-temporal remote sensing human intervention spatial variability NDVI trajectory

In Situ IR Spectroscopic Study on the Hydrogenation of 1,3-Butadiene on Fresh Mo_2C/γ-Al_2O_3 Catalyst

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China Petroleum Processing & Petrochemical Technology 2014年第4期16卷 32-37页

作者： Zhang Jing wu weicheng Liu Shiyang Liaoning Shihua University College of Chemistry Chemical Engineering and Environmental Engineering SINOPEC Tianjin Branch

The surface species formed from the adsorption of 1,3-butadiene and 1,3-butadiene hydrogenation over the fresh Mo2C/γ-Al2O3 catalyst was studied by in situ IR spectroscopy. It is found that 1,3-butadiene adsorption on the Mo2C/γ-Al2O3 catalyst mainly forms π-adsorbed butadiene(πs and πd) and σ-bonded surface species. These species are adsorbed mainly on the surface Moδ+(0<δ<2) sites as evidenced by co-adsorption of 1,3-butadiene and CO on the fresh Mo2C/γ-Al2O3 catalyst. The IR spectrometric analysis show that hydrogenation of 1,3-butadiene over fresh Mo2C/γ-Al2O3 catalyst produces mainly butane coupled with a small portion of butene. The selectivity of butene during the hydrogenation of 1,3-butadiene over fresh Mo2C/γ-Al2O3 catalyst might be explained by the adsorption mode of adsorbed 1,3-butadiene. Additionally, the active sites of the fresh Mo2C/γ-Al2O3 catalyst may be covered by coke during the hydrogenation reaction of 1,3-butadiene. The treatment with hydrogen at 673 K cannot remove the coke deposits from the surface of the Mo2C/γ-Al2O3 catalyst.

关键词： fresh Mo2C/γ-Al2O3 catalyst hydrogenation 1,3-butadiene in situ IR spectroscopy

Probing into Surface Sites of Fresh Mo_2N/Al_2O_3,Mo_2C/Al_2O_3 and MoP/Al_2O_3 Catalysts by CO Adsorption and In Situ FT-IR Spectroscopy

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China Petroleum Processing & Petrochemical Technology 2010年第4期12卷 43-45页

作者： Zhang Jing wu weicheng Yan Song Zhang Dan School of Chemistry and Materials Science Liaoning Shihua University Fushun 113001 Liaoning CAS Nanomaterials Development Co. Ltd.

The surface nature of fresh Mo2N/Al2O3, Mo2C/Al2O3 and/MoP/Al2O3 catalysts, which were synthesized directly in the IR cell to avoid passivation, were characterized by in situ IR spectroscopy with CO as a probe molecule. CO adsorbed on fresh catalysts showed characteristic IR bands at 2045 cm-1 for Mo2N/Al2O3 catalyst, 2054 cm-1 for MozC/Al2O3 catalyst and 2037 cm-1 for MoP/Al2O3 catalyst, respectively. A strong band at 2200 cm-1 for Mo2N/Al2O3 catalyst, which could be ascribed to NCO species formed when CO reacted upon surface active nitrogen atoms, and a weak band at 2196 cm-1 for Mo2C/Al2O3 catalyst, which could be attributed to CCO species, were also detected. CO adsorbed on fresh Mo2N/Al2O3 catalyst, Mo2C/Al2O3 catalyst and MoP/Al2O3 catalyst, showed strong molecular adsorption, just like noble metals. Our experimental results are bolstered by direct IR evidence demonstrating the similarity in surface electronic property between the fresh Mo2N/Al2O3, Mo2C/Al2O3 and MoP/Al2O3 catalysts and noble metals.

关键词： Mo2C/Al2O3 catalyst Mo2N/Al2O3 catalyst Mo2P/Al2O3 catalyst FT-IR CO

Studies on the Hydrogenation of Acetonitrile over Fresh Mo_2C/γ-Al_2O_3 Catalyst by In-situ IR Spectroscopy

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China Petroleum Processing & Petrochemical Technology 2015年第3期17卷 61-66页

作者： Zhang Jing wu weicheng Liu Chuang Ding Xiaoguang Chu Gang Zhang Jianguo Liaoning Shihua University College of Chemistry Chemical Engineering and Environmental Engineering Liaoning Shihua University School of Computer and Communication Engineering School of Medical Instrument and Food Engineering University of Shanghai for Science and Technology

The adsorption of acetonitrile, the co-adsorption of acetonitrile with CO, and hydrogenation of acetonitrile on fresh Mo2C/γ-Al2O3 catalyst were studied by in situ IR spectroscopy. It was found out that CH3CN exhibited strong interaction with the fresh Mo2C/γ-Al2O3 catalyst and was adsorbed mainly on Moδ+ sites of fresh Mo2C/γ-Al2O3 catalyst. Moreover, CH3CN could affect the shifting of IR spectra for CO adsorption towards a lower wave number. The IR spectroscopic study on acetonitrile hydrogenation showed that CH3CN could be easily hydrogenated in the presence of H2 on the Mo2C/γ-Al2O3 catalyst. Furthermore, it was observed that CH3 CN could be selectively hydrogenated to imines on fresh Mo2C/γ-Al2O3 catalyst. Additionally, the active sites of fresh Mo2C/γ-Al2O3 catalyst might be covered with coke during the hydrogenation reaction of acetonitrile. The treatment of catalyst with hydrogen at 673 K could not completely remove coke deposits on the surface of the Mo2C/γ-Al2O3 catalyst.

关键词： fresh Mo2C/γ-Al2O3 catalyst hydrogenation acetonitrile in situ IR spectroscopy

Study on the Influence of Ni Modifying on Phase Transformation and Photocatalytic Activity of TiO_2

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China Petroleum Processing & Petrochemical Technology 2014年第3期16卷 42-49页

作者： Wang Yan Zhang Jing Liu Shiyang Yan Song wu weicheng Xu Qian Li Can Liaoning Shihua University College of ChemistryChemical Engineering and Environmental Engineering Olefin Division of SINOPEC Tianjin Branch Dalian Institute of Chemical Physics Chinese Academy of SciencesState Key Laboratory of Catalysis

The Ni-modified TiO2 was synthesized using two methods including co-precipitation(Ni doped TiO2, Ni-TiO2) and wet impregnation(Ni loaded TiO2, Ni/TiO2). The surface and bulk crystalline phases of Ni-modified TiO2 were investigated by using X-ray diffractometry(XRD), UV Raman spectroscopy, TEM, and SEM. It is observed that Ni doping can promote the phase transition and grain size growth of TiO2. Moreover, the propagation of the rutile phase from the bulk into the surface region of TiO2 is increased when the Ni doping amount reaches up to 3%. However, in Ni/TiO2, it is found out that the surface and bulk phase transformation of TiO2 can be inhibited after impregnation of 1% of Ni on the TiO2. Compared with the co-precipitation method, Ni species may be more enriched in the surface of the Ni/TiO2 sample upon adoption of the impregnation method, and the direct contact of anatase particles of TiO2 is avoided. As a consequence, the phase transition in the surface and bulk region of TiO2 can be effectively inhibited by Ni loading. Additionally, the activity of the photocatalytic degradation of RhB on the 3Ni-TiO2-600 ℃ sample is higher than that on the 3 Ni/TiO2-600 ℃ sample. The phase junction formed between anatase and rutile in the surface region of 3Ni-TiO2-600 ℃ may the main reason for its high photocatalytic activity.

关键词： TiO2 Ni modifying wastewater treatment UV Raman spectroscopy phase transformation

Heat units-based potential yield assessment for cotton production in Uzbekistan

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International Journal of Agricultural and Biological Engineering 2021年第6期14卷 137-144页

作者： Gianni Montanaro Vinay Nangia Prasanna Gowda Shukhrat Mukhamedjanov Azamat Mukhamedjanov Mira Haddad Tulkun Yuldashev weicheng wu International Center for Agricultural Research in the Dry Areas(ICARDA) Rabat InstitutsRue Hafiane CherkaouiRabatMorocco Forage and Livestock Production Research Unit USDA-ARS Grazinglands Research LaboratoryEl RenoOK 73036USA Scientific-Information Center of the Interstate Coordination Water Commission of the Central Asia(SIC ICWC) TashkentUzbekistan International Water Management Institute TashkentUzbekistan Key Laboratory of Digital Land and Resources East China Institute of TechnologyNanchang 330013China

Cotton yields in Uzbekistan are significantly lower than those in similar agro-climatic regions,requiring the estimation of crop potential and baseline yield to track progress of production enhancement *** current study estimated potential cotton development and baseline yield(maximum given no production constraints)using total heat units(THU)and potential cotton yield(PCY),*** were based on heat units(HU)for a 30-year(1984-2013)***-term average THU and PCY,as well as PCY at three different exceedance probabilities(p=0.99,p=0.80,and p=0.75),were calculated for 21 selected weather stations across cotton-growing areas of *** confirmation that the current planting date(April 15)is optimal,a comparison of THU with the accepted cotton production cutoff threshold(1444°C)suggested that areas with lower elevations and latitudes are more appropriate for cotton *** gap analysis(relative difference between long-term average PCY and actual yields)confirmed that Uzbekistan cotton production is below potential,while the spatial distribution of yield gaps outlined where efforts should be *** near the stations of Nukus,Kungrad,Chimbay,and Syrdarya should be further investigated as benefit/cost ratio is highest in these areas.A comparison between state-set yield targets and PCY values,taking into account climatic variability,suggested that all areas except Jaslyk,Nurata,and Samarkand have safe,appropriate *** results present a starting-point to aid in strategic actions for Uzbekistan cotton production improvement.

关键词： cotton potential cotton yield yield gap heat unit Uzbekistan agriculture climatic variability target

Payload-free protein nanoparticles target inflamed colons to restore intestinal barrier integrity for effectively treating inflammatory bowel diseases

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Aggregate 2024年第4期5卷 113-125页

作者： Mei Yang Honglan Shen Suting Zhong Zongpu Xu Xiangyu Liu weicheng wu Chuanbin Mao Mingying Yang Institute of Applied Bioresource Research College of Animal ScienceZhejiang UniversityHangzhouChina School of Materials Science and Engineering Zhejiang UniversityHangzhouChina Food Science Institute Zhejiang Academy of Agricultural SciencesHangzhouChina Department of Biomedical Engineering The Chinese University of Hong KongHong Kong SARChina

Anti-inﬂammatory compounds,delivered as a payload to the gastrointestinal tract(GIT)by carriers,still cannot treat inﬂammatory bowel diseases without avoid-ing side ***,we developed payload-free protein nanoparticles(PNPs)that crossed GIT to retain in the colon and treat colitis by restoring intestinal bar-rier integrity by modulating gut microbiome and ***ﬁcally,PNPs,orally administered to mice with acute colitis,reached the colon within three ***,PNPs improve gut microbiota dysbiosis to reverse metabolism bal-ance,suppressing the expression of tumor-necrosis factorαand toll-like receptor 4 that restores the intestinal barrier *** then ameliorated colon inﬂam-mation and attenuated gut microbiota dysbiosis by exerting probiotic effects on gut microbiota,treating colitis in a week more effectively than the clinically often used 5-aminosalicylic acid without causing undesired side *** PNPs repre-sent safe,sustainable,and cost-effective therapeutics for treating inﬂammatory and metabolic diseases by eliminating microbial and metabolomic imbalance.

关键词： gut metabolites gut microbiota inﬂammatory bowel diseases(IBDs) protein nanoparticles(PNPs)

FT-IR Spectroscopic Investigation of Co-adsorption of Acetonitrile and CO on Fresh Mo_2C/Al_2O_3 Catalyst

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China Petroleum Processing & Petrochemical Technology 2009年第4期11卷 59-61页

作者： Zhang Jing~1 wu weicheng~2 Jin Ziming~1 (1.School of Chemistry and Materials Science,Liaoning University of Petroleum & Chemical Technology,Fushun 113001 2.Liaoning Academy of Nanomaterials Development Co.Ltd.) School of Chemistry and Materials Science Liaoning University of Petroleum and Chemical Technology Fushun 113001 China Liaoning Academy of Nanomaterials Development Co. Ltd. China

The adsorption of acetonitrile and its co-adsorption with CO on fresh Mo_2C/Al_2O_3 catalyst have been studied by insitu FT-IR *** adsorbed CH_3CN and CH_3CH_2NH_2 were formed after CH_3CN adsorption on the Mo_2C/ Al_2O_3 *** appearance of a strong band at 1578 cm^(-1) indicates that CH_3CN was reactive with hydrogen on the Mo_2C/Al_2O_3 catalyst.

关键词： Mo_2C/Al_2O_3 catalyst FT-IR spectroscopy CO acctonitrile

FT-IR investigation of the co-adsorption of acetonitrile and CO on Mo2C/Al2O3

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FT-IR investigation of the co-adsorption of acetonitrile and...