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Preparation and microstructure of CuO-CoO-MnO/SiO2 nanocomposite aerogels and xerogels as catalyst carriers

Progress in Natural Science:Materials International 2011年第4期21卷 330-335页

作者： Yue-qing ZHAO~1,Ying-hua LIANG~2,Xi-zhe ZHAO~3,Qian-yi JIA~4.Hong-sheng LI~4.1.College of Light Industry,hebei United university,tangshan 063000,china 2.College of Chemical Engineering,hebei United university,tangshan 063.09,china 3.College of Printing and Packaging Engineering,Beijing Institute of Graphic Communication,Beijing 102600,china 4.College of Materials Science and Engineering,hebei United university,tangshan 063.09,china [a] College of Light Industry Hebei United University Tangshan 063000 China [b] College of Chemical Engineering Hebei United University Tangshan 063009 China [c] College of Printing and Packaging Engineering Beijing Institute of Graphic Communication Beijing 102600 China [d] College of Materials Science and Engineering Hebei United University Tangshan 063009 China

CuO-CoO-MnO/SiO2nanocomposite aerogels and xerogels were prepared using tetraethyl orthosilicate（TEOS） as Si source,and aqueous solution of Cu,Co and Mn acetates as the precursor via sol-gel process,CO2supercritical drying（SCD） technique or ambient pressure drying *** microstructure of the CuO-CoO-MnO/SiO2nanocomposite aerogels and xerogels were characterized by field emission scanning electron microscopy（FE-SEM）,transmission electron microscopy（TEM） and X-ray diffraction（XRD）.The specific surface area,pore size and pore size distribution of the nanocomposite aerogels and xerogels were determined by the Brunauer-Emmett-Teller（BET） *** results showed that CuO-CoO-MnO/SiO2nanocomposite aerogels are porous,with a pore size distribution of 2-50 nm,an average pore size of 19.4.nm,a specific surface area of 384.9 m2/g and a particle size distribution of 10-150 nm,whereas the pore size distribution of CuO-CoO-MnO/SiO2composite xerogels is 1.7-128.6 nm,the average pore size is only 9.9 nm,the specific surface area is only 99.1 m2/g,and the particle size distribution is 100-500 *** structure of CuO-CoO-MnO/SiO2nanocomposite aerogels is favorable to increase the loading of catalysts.

关键词： composite aerogel composite xerogel catalyst carrier preparation microstructure

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Time-stepping for multibody dynamics with friction-affected bilateral constraints

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Progress in Natural Science:Materials International 2009年第12期19卷 1799-1804页

作者： Li Fu~(a,b,*),Qi Wang~a,Shimin Wang~a a Department of dynamics and control,Behang university,Beijing 100191,china b Science School,hebei polytechnic university,tangshan 063000,china [a]Department of dynamics and control Behang University Beijing 100191 China [b]Science School Hebei Polytechnic University Tangshan 063000 China

The dynamics of multibody systems with friction-affected bilateral constraints is essentially different from those of smooth multibody *** this paper,general modeling and numerical methods for this kind of friction-affected system are *** friction-affected bilateral constraint is modeled by splitting it into two unilateral constraints opposite to each *** constraint equalities are replaced with complementarity inequalities to avoid the absolute value terms in the dynamic equations.A linear complementarity problem time-stepping scheme is presented for simulation that does not suffer from the difficulties of enumeration(known as Delassus’ problem).The algorithm has the advantage that it needs no detection for stick-slip transition when neglecting the difference between the static and kinetic friction *** method is carried out in an example to analyze the nonsmooth nonlinear behavior of a typical mechanism.

关键词： Friction Multibody dynamics Unilateral constraints Time-stepping scheme

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Dynamic security risk assessment and optimization of power transmission system

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Science china(Technological Sciences) 2008年第6期51卷 713-723页

作者： YU YiXin1 & WANG DongTao1,2 1 Key Laboratory of Power System Simulation and Control of Ministry of Education, Tianjin university, Tianjin 300072, china 2 School of Computer & Automation, hebei polytechnic university, tangshan 063.09, china 1. Key Laboratory of Power System Simulation and Control of Ministry of Education Tianjin University Tianjin 300072 China 2. School of Computer & Automation Hebei Polytechnic University Tangshan 063009 China

The paper presents a practical dynamic security region (PDSR) based dynamic security risk assessment and optimization model for power transmission system. The cost of comprehensive security control and the influence of uncertainties of power injections are considered in the model of dynamic security risk assessment. The transient stability constraints and uncertainties of power injections can be considered easily by PDSR in form of hyper-box. A method to define and classify contingency set is presented, and a risk control optimization model is given which takes total dynamic insecurity risk as the objective function for a dominant con-tingency set. An optimal solution of dynamic insecurity risk is obtained by opti-mizing preventive and emergency control cost and contingency set decomposition. The effectiveness of this model has been proved by test results on the New Eng-land 10-genarator 39-bus system.

关键词： power transmission system risk assessment dynamic security practical dynamic security region (PDSR) comprehensive security control optimization

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In-situ Synthesis and Formation Mechanism ofTiN-Al_2O_3/Al Composite

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Journal of Materials Science & Technology 1998年第1期14卷 77-79页

作者： Chunxiang CUP and Renjie WU (State Key Lab. for MMCs, Shanghai Jiaotong university, Shanghai 200030, china)Jianran YAN and Guobin LI (hebei polytechnic university Tianjin 300132, china) Shanghai Jiao Tong Univ State Key Lab MMCs Shanghai 200030 Peoples R China hebei Polytech Univ Tianjin 300132 Peoples R China

The synthesis of TiN and Al2O3 by in situ injection of reactive nitrogen gas into molten Al alloys has been evaluated over the temperature range from 1000 to 1600℃. It is shown that TiN and Al2O3 can be formed in melt with nitrogen and surplus oxygen (in vacuum room of the induction furnace) as the reactive gases over 1000℃. Up to 2.1 wt pct Al2O3 and 5.2 wt pct of TiN in situ phases in an Al alloy has been formed in a range of size from 0.8 to 5 μm. The formation mechanism of TiN and Al2O3 is discussed in this paper.

关键词： Al Ti Res

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Vision navigation algorithm for mine agent based on quaternion

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中国有色金属学会会刊：英文版 2011年第S3期21卷 610-615页

作者： LI Ke-zhao1, 4. LEI Wei-wei1, 2, GUO Zeng-zhang1, 2, WU Li-xin3, ZHANG Qin4.1. School of Survey and Land Information Engineering, Henan polytechnic university, Jiaozuo 4.4.03, china 2. Key Laboratory of Mine Spatial Information Technologies of State Bureau of Surveying and Mapping, Henan polytechnic university, Jiaozuo 4.4.03, china 3. College of Resources and Civil Engineering, Northeastern university, Shenyang 110819, china 4. College of Geology Engineering and Geomatics, Chang’an university, Xi’an 710054. china [a] School of Survey and Land Information Engineering Henan Polytechnic University Jiaozuo 454003 China [b] Key Laboratory of Mine Spatial Information Technologies of State Bureau of Surveying and Mapping Henan Polytechnic University Jiaozuo 454003 China [c] College of Resources and Civil Engineering Northeastern University Shenyang 110819 China [d] College of Geology Engineering and Geomatics Chang'an University Xi'an 710054 China

Autonomous relative navigation is the key technology in mining or rescuing. On the basis of mine requirement and the theories of machine vision, an autonomous relative navigation algorithm for mine agent based on quaternion was proposed. In rotation transformation, this algorithm was represented by using quaternion. Because the Jacobi matrix of this method is lower than that of Hall algorithm, the calculation efficiency is improved by using this algorithm. The results of these experiments show that the computation burden of this algorithm based on quaternion is about half that of Hall algorithm. This algorithm based on quaternion is improved as a valid way to solve the problem of mine real-time navigation.

关键词： quaternion mine agent vision navigation

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4. and application of land reclamation in mining area

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中国有色金属学会会刊：英文版 2005年第S1期15卷 49-52页

作者： XIE Hong-quan~(1,2 ), HU Zhen-qi~1, JING Hai-tao~3, GAO Yong-jiu~(4., CHEN Qiu-ji~(5), FENG Zhong-ke~(6) (1. china university of Mining and Technology(Beijing Campus), Beijing 100083, china 2. hebei {4. university, tangshan 063.09, china 3. Xuzhou Normal university, Xuzhou 221009, china 4. tangshan Branch, china Coal Research Institute, tangshan 063012, china 5. Henan {4. university, Jiaozuo 4.4.00, china 6. Beijing Forestry university, Beijing 100083, china) china Univ Min & Technol Beijing 100083 Peoples R China hebei Polytech Univ Tangshan 063009 Peoples R China Xuzhou Normal Univ Xuzhou 221009 Peoples R China china COal Res Inst Tangshan Branch Tangshan 063012 Peoples R China Henen Polytech Univ Jiaozuo 454000 Peoples R China Beijing Forestry Univ Beijing 100083 Peoples R China

4. products are basic mode of digitized products that are made by combining model remote sensing with GIS technology, and have already brought everybody’s high recognition. Coal mining makes great destroy to land of coal mining area, and ecological environment becomes worse, therefore land reclamation of mining area has already turned into investigated emphases. 4. meaning is briefly introduced, and its six characteristics are expounded in this paper. Production technique and application status of 4. are summarized, and existed problems are analyzed in developed aspect. Land reclamation of mining area is a complex system engineering, and application of 4. products can be impenetrated in whole process. Otherwise 4. has broad application scope in land management of mining area and mine information construction. Compound of remote sensing and DTM can be apply to solve mine survey, monitor of surface and marginal slope and so on.

关键词： 4. produce land reclamation remote sensing image data resource

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Quantitative analysis on soil erosion based on 3S technology

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中国有色金属学会会刊：英文版 2005年第S1期15卷 82-85页

作者： JING Hai-tao~1, XIE Hong-quan~(2, 3), FU Mei-chen~2, FENG Zhong-ke~4.(1. Xuzhou Normal university, Xuzhou 221009, china 2. china university of Mining and Technology(Beijing Campus), Beijing 100083, china 3. hebei polytechnic university, tangshan 063.09, china 4. Beijing Forestry university, Beijing 100083, china Xuzhou Normal Univ Xuzhou 221009 Peoples R China china Univ Min & Technol Beijing 100083 Peoples R China hebei Polytech Univ Tangshan 063009 Peoples R China Beijing Forestry Univ Beijing 100083 Peoples R China

The quantitative analysis on soil erosion is very significant for macro-decision of soil loss, for quick control of natural disasters and for system of periodical report. Based on the research of 3S(GPS, GIS and RS), the special information can be obtained by GPS or RS. Digital elevation model can be formed by GIS software, and at the same time, we can get some vector graph, such as landuse, vegetation type and soil type. Then the soil erosion of research area was calculated by USLE. The methods and techniques were discussed, including how to carve up polygons, how to capture the values of factors and how to differentiate the erosion intensity.

关键词： soil erosion USLE GPS GIS RS

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Relationships between bacterial-algal proliferating and mass extinction in the Late Devonian Frasnian-Famennian transition:Enlightening from carbon isotopes and molecular fossils

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Science china Earth Sciences 2005年第10期48卷 1656-1665页

作者： GONG Yiming1,2, XU Ran1, TANG Zhongdao1, SI Yuanlan3 & LI Baohua4.1. Faculty of Earth Science and State Key Laboratory of Geological Processes and Mineral Resources, china university of Geosciences, Wuhan 4.0074. china 2. Institute of Resources & Environments, Henan polytechnic university, Jiaozuo 4.4.03, china 3. Department of Computer Science, South-Central university for Nationalities, Wuhan 4.0074. china 4. Laboratory of Marine Geology, Tongji university, Shanghai 200092, china Faculty of Earth Science and State Key Laboratory of Geological Processes and Mineral Resources china university of Geosciences Wuhan china Institute of Resources & Environments Henan polytechnic university Jiaozuo china Department of Computer Science South-Central university for Nationalities Wuhan china Laboratory of Marine Geology Tongji university Shanghai china

Studies show positive shifts of inorganic and organic carbon isotope values (δ 13Ccarb and δ 13Ckerogen) from +0.4. (‰ V-PDB) to +3.54.(‰ V-PDB) and from ?29.38 (‰ V-PDB) to ?24.14.(‰ V-PDB), respectively, B* (Ba* = Ba/ (Al2O3 X 15%)) values from 0.015 to 0.14., TOC values from 0.02% to 0.21%, V/Cr values from 0.3 to 2.0, Sr/Ba values from 3.20 to 4..50 in the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone of the Yangdi sec-tion deposited in carbonate slope facies of Guilin, Guangxi, South china, which indicates that biomass, productivity, organic carbon burial and salinity increase and that oxygenation near the boundary between sediments and waters decreases from the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone. Abundance of molecular fossils increases and normal alkanes, isoprenoid hydrocarbon, terpanes and steranes are dominated from the Late Devonian Frasnian to the bottom of Famennian, which shows that the predecessors of molecular fossils of the Frasnian-Famennian (F-F) transition are dominated by marine phytoplankton, zooplankton and benthic bacteria with no photosynthesis. Therefore, it is considered that the F-F transitional mass extinction with a multistage, selection and global synchronizing was caused by bacte-rial-algal proliferating, continuing deterioration of the shallow marine ecoenvironment of the mid-dle-lower latitudes. A simple cause and effect chain can be expressed as: appearance of seed plants and multi-storied forests → enhanced chemical and biochemical weathering and pe-dogenesis → wide development of soils → increasing riverine nutrient fluxes in epicontinental sea → from superoligotrophic to eutrophic in epicontinental sea → proliferating of marine phyto-plankton and zooplankton → frequent red tide and anoxia → mass extinction of shallow marine organisms in the middle-lower latitudes. It is worth notice that the factor drawdown of atmos-pheric Pco2, climatic cooling and sea level falling c

关键词： mass extinction, bacteria-algae, carbon isotopes, molecular fossils, biodiversity, Late Devonian, Guangxi, South china.

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Spatio-temporal model for soil characteristic of reclamation land

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中国有色金属学会会刊：英文版 2005年第S1期15卷 45-48页

作者： CHEN Qiu-ji~(1, 2), HU Zhen-qi~1, FU Mei-chen~3, XIE Hong-quan~4. HAO Hai-fu~5 (1. china university of Mining and Technology(Beijing Campus), Beijing 100083, china 2. Henan polytechnic university, Jiaozuo 4.4.00, china 3. china university of Geosciences, Beijing 100083, china 4. hebei polytechnic university, tangshan 063.09, china 5. china Railway Shiqiju Group Corporation, Taiyuan 030600, china) china Univ Min & Technol Beijing 100083 Peoples R China Henen Polytech Univ Jiaozuo 45400 Peoples R China china Univ Geosci Beijing 100083 Peoples R China hebei Polytech Univ Tangshan 063009 Peoples R China china Railway Shiqiju Grp Corp Taiyuan 030600 Peoples R China

The development of spatio-temporal data model is introduced. According to the soil characteristic of reclamation land, we adopt the base state with amendments model of multi-layer raster to organize the spatio-temporal data, using the combined data structure on linear quadtree and linear octree to code. The advantage of this model is that it can easily obtain the information of certain layer and integratedly analyze the data with other methods. Then, the methods of obtain and analyses are introduced. The method can provide a tool for the research of the soil characteristic change and spatial distribution in reclamation land.

关键词： reclamation soil spatio-temporal data model linear quad-tree linear octree

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The discussion of starting experimental courses in the teaching of Linear Algrbra

The discussion of starting experimental courses in the teach...

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2010 The 2nd International Conference on Industrial Mechatronics and Automation (ICIMA 2010)

作者： Xiujuan Xu College of Science hebei polytechnic university tangshan 063.09 {4. Jincai Chang College of Science hebei polytechnic university tangshan 063.09 {4. Baoxiang Liu College of Science hebei polytechnic university tangshan 063.09 {4. Dianxuan Gong College of Science hebei polytechnic university tangshan 063.09 {4.

Linear algebra is an important fundamental course to each profession students in engineering colleges,having special features which are different from other courses in improving the quality of *** analyzing the drawbacks of teaching linear algebra traditionally,combining with the new situations and new problems today’s higher education faced,contacting with many years’ self teaching experience,this paper made clear,in the course of teaching,the necessity and feasibility of the introduction of experimental courses,and put forward a reasonable implementing scheme to open experimental course of linear ***,experimental teaching stimulated students’ learning interest,and enhanced the students’ capacity of analyzing and solving practical problems using the knowledge of linear algebra,which would be beneficial to the cultivation of technology innovation talents of today’s students.

关键词： Linear Algebra Mathematics software Mathematical Experiments

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