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Soil Erosion and Its Basic Characteristics at Karst Rocky-desertified Land Consolidation Area: A Case Study at Muzhe Village of Xichou County in Southeast Yunnan, China

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Journal of Mountain Science 2010年第1期7卷 55-72页

作者： yang Zisheng yang Longfei zhang Bosheng Institute of Land & Resources and Sustainable Development Yunnan University of Finance and Economics Kunming650221 China

Xichou County of Wenshan Zhuang and Miao Autonomous Prefecture in southeast Yunnan is one of the karst mountainous areas in southwest China showing typical rock desertification. During this study, we set up three soil erosion contrast test spots at Muzhe Village, Benggu Township, Xichou County, which was the birthplace of the Xichou rock-desertified land consolidation mode. The three spots included the terrace land spot （already consolidated land）, sloping land spot （unconsolidated sloping land under rock desertification）, and standard runoff spot （bare land spot）. In 2007, a whole-year complete observation was conducted during the rainy season and ＂rainfall-erosion＂ data were obtained for 32 times. Our analysis showed that during the entire observation period, the number of the rainfalls that led to soil erosion accounted for 34.04% of the number of all rainfalls and the amount of the rainfalls that led to soil erosion accounted for 84.17% of the total amount of all rainfalls. The average erosive rainfall standard in the three test spots was 11.0mm, slightly higher than the lO mm standard that has been adopted all over China, but lower than the 12.7 mm standard of the US and the 13.0 mm standard of Japan. According to single-factor analysis, the soil loss in the sloping land spot （L2） and that in the bare land spot （L3） are correlated to certain extent to manyother factors, including the single precipitation （P）, rainfall intensity during the maximum ten minutes （Lo）, rainfall intensity during the maximum 20 minutes （I2o）, rainfall intensity during the maximum 30 minutes （I30）, rainfall intensity during the maximum 40 minutes （I4o）, and rainfall intensity during the maximum 6o minutes （I60）. Among these factors, they are of the highest relativity with I6o. According to double-factor analysis, both L2 and L3 are of good relativity with P and I60. According to multi-factor analysis, L2 and L3 are also of good relativity with seven rainfall indexes, namely, P, Ia （ave

关键词： karst mountainous area rockdesertification land consolidation soil erosion testspot Xichou County

Graft of Chiral Amino Alcohol onto Poly（menthyl vinyl ketone） and the Grafted Polymer＇s Inducement to the Asymmetric Addition of Phenylacetylene to Aromatic Ketone

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Chemical Research in Chinese Universities 2015年第4期31卷 669-673页

作者： LIU Can ZHOU Ya yang Liwen yang Nianfa zhang Anlin Key Laboratory of Environmentally Friendly Chemistry and Applications Ministry of Education College of Chemistry Xiangtan University Xiangtan 411105 P. R. China

A new kind of optically active polymer bearing chiral amino alcohol was prepared by means of graft. The resulting grafted polymer was obtained as follows. First, the carbonyl of optically active helical poly（menthyl vinyl ketone）（poly-MVK） was reduced to hydroxyl group with lithium aluminum hydride as a reductant to yield poly（1-menthyl-2-propen-1-ol）（poly-MPO）. Second, the hydroxyl group of poly-MPO reacted with epichlorohydrin to yield methyloxirane-loading poly-MPO[（poly-MPO）-MO]. Third, the（poly-MPO）-MO reacted with amine to pro- duce optically active polymer bearing chiral amino alcohol[（poly-MPO）-APO]. The （poly-MPO）-APO was applied to the asymmetric addition of phenylacetylene to aromatic ketone. Good enantioselectivities were achieved and the catalyst could be recovered and reused 5 times with unchanged enantioselectivity and slightly decreased activity.

关键词： Chiral amino alcohol Graft Poly(menthyl vinyl ketone) Enantioselective addition

Experimental studies on ozonation of ethylenethiourea

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Journal of Environmental Sciences 2011年第1期23卷 65-69页

作者： Xinyu Dong Junwang Meng Bo yang yang zhang Jie Gan XiShu Jinian Shu Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China. E-mail: xinyudong@***

The experimental study on ozonation of ethylenethiourea （ETU） is conducted. The reaction of gas-phase ETU with 0.63 × 10^-6 mol/L ozone is carried out in a 200-L reaction chamber. The secondary organic aerosol （SOA） resulted from the ozonation of gas-phase ETU is observed with a scanning mobility particle size （SMPS）. The rapid exponential growth of SOA reveals that the atmospheric lifetime of ETU vapor towards ozone reaction is less than four days. The ozonation of dry ETU particles, ETU-contained water droplets and ETU aqueous solution is investigated with a vacuum ultraviolet photoionization aerosol time-of-flight mass spectrometer （VUV- ATOFMS）. The formation of 2-imidazoline is observed in the ozonation of dry ETU particles and ETU-contained water droplets. The formation of 2-imidazoline and ethvlenerea is observed in the ozonation of ETU aqueous solution.

关键词： ethylenethiourea pesticide ozonation VUV photoionization AMS

Processing,microstructure,and properties of porous ceramic composites with directional channels

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Journal of Materials Science & Technology 2024年第1期168卷 1-15页

作者： Bo zhang yang yang Xueling Fan Key Laboratory of Service Performance and Protection Technology in Extreme Environments Xi’an Jiaotong UniversityXi’an 710049China State Key Laboratory for Strength and Vibration of Mechanical Structures School of Aerospace EngineeringXi’an Jiaotong UniversityXi’an 710049China

Porous ceramic composites with directional microchannels from micrometer to dozens of micrometer levels have attracted more and more attention in various fields including aerospace,biomedicines,and thermal insulation due to their excellent fluid permeability,mechanical properties,*** this article,we summarize the recent directional porous ceramics developments including their main processing routes and respective ***,the properties get from different processing routes have been com-pared and analyzed in terms of microstructures,mechanical properties,and *** has been given to the deeper understanding which can allow one to control the microstructural features of these porous ceramic composites to obtain the desired *** work can provide a useful reference for the development and application of porous ceramic composites with directional microchan-nels.

关键词： Porous ceramic composites Directional microchannels Processing routes Permeability

The Mechanisms of Brassinosteroids＇ Action： From Signal Transduction to Plant Development

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Molecular Plant 2011年第4期4卷 588-600页

作者： Cang-Jin yang Chi zhang yang-Ning Lu Jia-Qi Jin Xue-Lu Wang State Key Laboratory of Genetic Engineering and Institute of Plant Biology School of Life Sciences Fudan University Shanghai 200433 People's Republic of China

Brassinosteroids play diverse roles in plant growth and development. Plants deficient in brassinosteroid （BR） biosynthesis or defective in signal transduction show many abnormal developmental phenotypes, indicating the importance of both BR biosynthesis and the signaling pathway in regulating these biological processes. Recently, using genetics, proteomics, genomics, cell biology, and many other approaches, more components involved in the BR signaling pathway were identified. Furthermore, the physiological, cellular, and molecular mechanisms by which BRs regulate various aspects of plant development, are being discovered. These include root development, anther and pollen development and formation, stem elongation, vasculature differentiation, and cellulose biosynthesis, suggesting that the biological functions of BRs are far beyond promoting cell elongation, This review will focus on the up-to-date progresses about regulatory mechanisms of the BR signaling pathway and the physiological and molecular mechanisms whereby BRs regulate plant growth and development.

关键词： Arabidopsis brassinosteroid cross-talk phosphorylation plant development signaling pathway stresses.

Fixed-Time Sliding Mode Control With Varying Exponent Coefficient for Modular Reconfigurable Flight Arrays

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 514-528页

作者： Jianquan yang Chunxi yang Xiufeng zhang Jing Na Faculty of Mechanical and Electrical Engineering Kunming University of Science and TechnologyKunming 650500 Yunnan International Joint Laboratory of Intelligent Control and Aoolication of Advanced Equipment Kunming 650500China IEEE

The modular system can change its physical structure by self-assembly and self-disassembly between modules to dynamically adapt to task and environmental requirements. Recognizing the adaptive capability of modular systems, we introduce a modular reconfigurable flight array(MRFA) to pursue a multifunction aircraft fitting for diverse tasks and requirements,and investigate the attitude control and the control allocation problem by using the modular reconfigurable flight array as a platform. First, considering the variable and irregular topological configuration of the modular array, a center-of-mass-independent flight array dynamics model is proposed to allow control allocation under over-actuated situations. Secondly, in order to meet the stable, fast and accurate attitude tracking performance of the MRFA, a fixed-time convergent sliding mode controller with state-dependent variable exponent coefficients is proposed to ensure fast convergence rate both away from and near the system equilibrium point without encountering the singularity. It is shown that the controller also has fixed-time convergent characteristics even in the presence of external disturbances. Finally,simulation results are provided to demonstrate the effectiveness of the proposed modeling and control strategies.

关键词： Control allocation dynamic model fixed-time stabilization modular reconfigurable flight array(MRFA) sliding mode

Recent progress on copper catalysts with different surface states for CO_(2)electroreduction

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Journal of Energy Chemistry 2024年第1期88卷 10-27,I0001页

作者： Wenjun zhang yang yang Donggang Guo Lu Liu Tianjin Key Laboratory of Environmental Remediation and Pollution Control College of Environmental Science and EngineeringNankai UniversityTianjin 300350China Shanxi Laboratory for Yellow River College of Environment and ResourceShanxi UniversityTaiyuan 030006ShanxiChina

The electrochemical carbon dioxide reduction reaction(eCO_(2)RR),which converts CO_(2)into various hydrocarbons or alcohols,has been extensively researched because it promises a sustainable energy ***,only copper(Cu)can currently achieve stable and efficient hydrocarbon conversion in the eCO_(2)***,understanding the catalytic mechanisms and summarizing the research progress on synthesis strategies of Cu catalysts are essential for the eCO_(2)*** paper reviews Cu catalysts with different surface states of Cu catalysts:oxide-derived Cu,Cu nanoparticles,Cu single atoms,and Cu *** then reviews the development and progress of different Cu-catalyst preparation methods in recent years,focusing on the activity and selectivity of *** revealing the tendencies of catalytic selection and deep reactive mechanisms of Cu catalysts with four different surface states,this review can guide the subsequent construction of catalysts and provides an understanding of catalytic mechanisms.

关键词： eCO_(2)RR Oxide-derived Cu Cu nanoparticles Cu single atoms Cu nanoclusters

Prediction of lime utilization ratio of dephosphorization in BOF steelmaking based on online sequential extreme learning machine with forgetting mechanism

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 508-517页

作者： Runhao zhang Jian yang Han Sun Wenkui yang State Key Laboratory of Advanced Special Steel School of Materials Science and EngineeringShanghai UniversityShanghai 200444China

The machine learning models of multiple linear regression(MLR),support vector regression(SVR),and extreme learning ma-chine(ELM)and the proposed ELM models of online sequential ELM(OS-ELM)and OS-ELM with forgetting mechanism(FOS-ELM)are applied in the prediction of the lime utilization ratio of dephosphorization in the basic oxygen furnace steelmaking *** ELM model exhibites the best performance compared with the models of MLR and ***-ELM and FOS-ELM are applied for sequential learning and model *** optimal number of samples in validity term of the FOS-ELM model is determined to be 1500,with the smallest population mean absolute relative error(MARE)value of 0.058226 for the *** variable importance analysis reveals lime weight,initial P content,and hot metal weight as the most important variables for the lime utilization *** lime utilization ratio increases with the decrease in lime weight and the increases in the initial P content and hot metal weight.A prediction system based on FOS-ELM is applied in actual industrial production for one *** hit ratios of the predicted lime utilization ratio in the error ranges of±1%,±3%,and±5%are 61.16%,90.63%,and 94.11%,*** coefficient of determination,MARE,and root mean square error are 0.8670,0.06823,and 1.4265,*** system exhibits desirable performance for applications in actual industrial pro-duction.

关键词： basic oxygen furnace steelmaking machine learning lime utilization ratio dephosphorization online sequential extreme learning machine forgetting mechanism

The application of machine learning under supervision in identification of shale lamina combination types——A case study of Chang 7_(3)sub-member organic-rich shales in the Triassic Yanchang Formation,Ordos Basin,NW China

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Petroleum Science 2021年第6期18卷 1619-1629页

作者： Yuan-Yuan zhang Ke-Lai Xi Ying-Chang Cao Bao-Hai Yu Hao Wang Mi-Ruo Lin Ke Li yang-yang zhang Deep Oil and Gas Key Laboratory China University of Petroleum(East China)QingdaoShandong 266580China No.7 Oil Recovery Plant of PetroChina Changqing Oilfield Company Xi'anShaanxi 710000China Fengcheng Oil Recovery Plant of PetroChina Xinjiang Oilfield Company KaramayXinjiang 834000China

Organic rich laminated shale is one type of favorable reservoirs for exploration and development of continental shale oil in ***,with limited geological data,it is difficult to predict the spatial distribution of laminated shale with great vertical *** solve this problem,taking Chang 73 sub-member in Yanchang Formation of Ordos Basin as an example,an idea of predicting lamina combinations by combining'conventional log data-mineral composition prediction-lamina combination type identification'has been worked out based on machine learning under supervision on the premise of adequate knowledge of characteristics of lamina mineral ***,the main mineral components of the work area were figured out by analyzing core data,and the log data sensitive to changes of the mineral components was extracted;then machine learning was used to construct the mapping relationship between the two;based on the variations in mineral composition,the lamina combination types in typical wells of the research area were identified to verify the *** results show the approach of'conventional log data-mineral composition prediction-lamina combination type identification'works well in identifying the types of shale lamina *** approach was applied to Chang 73 sub-member in Yanchang Formation of Ordos Basin to find out planar distribution characteristics of the laminae.

关键词： Organic-rich shale Laminae combination Conventional logs Machine learning Ordos Basin