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

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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 063009,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 063009,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

Construction and application of formal ontology for mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 577-582页

作者： CHENG Gang 1, 2, ZHANG Yin-ling1, 2, WANG Fei 1 ,2, ZHANG Zhen-hui 3, GUO Yu-xiang1, 2 1. Key Laboratory of Mine Spatial Information Technologies of State Bureau of Surveying and Mapping, Henan Polytechnic university, Jiaozuo 454003, china 2. School of Surveying and land Information engineering, Henan Polytechnic university, Jiaozuo 454003, china 3. qingdao Branch of Naval Aeronautical engineering Institute, qingdao 266041, china Henan Polytech Univ Key Lab Mine Spatial Informat Technol State Bur Surveying & Mapping Jiaozuo 454003 Peoples R China Henan Polytech Univ Sch Surveying & Land Informat Engn Jiaozuo 454003 Peoples R China Naval Aeronaut Engn Inst Qingdao Branch Qingdao 266041 Peoples R China

Digital mine is the only way for the development of mining industry in china. Due to lack of appropriate standards and norms, and different awareness in the field of digital mine among academia and industry insiders, the meaning for digital mine is still unclear. Starting from the nature of mining and removing of views of specialized fields, this paper constructs formal ontology for digital mine and proposes the four levels for it. The ontology clarifies the concept world for digital mine, defines the meaning of concepts and relations clearly, provides a reference for the standard construction for digital mine and provides a unified semantic framework for the integration of heterogeneous mine data. Meanwhile, it can provide formal reasoning knowledge for expert system of digital mine and improve the intelligence and automation while the machine automatically interpreting and processing mine spatial data.

关键词： Digital mine formalization ontology concept world semantic share

NUMERICAL SIMULATION OF WAVE-INDUCED CURRENT WITH VERTICALLY VARIED RADIATION STRESS

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Journal of Hydrodynamics 2010年第2期22卷 254-259页

作者： ZHANG Jing LIANG Bing-chen LI Hua-jun college of engineering Ocean University of China Qingdao 266100 China

This article analyzes the vertical structure of the onshore current including the wave-induced current by an equation developed for the radiation stress against water depth.A coupled model COHERENS-SED is adopted to calculate the wave,tidal current,wave-induced current and sediment *** applying the new model to Yangpu Bay,its reliability is *** an ideal coastal domain is defined to simulate the nearshore current and wave setup with normal incident *** numerical and experimental results for the vertical structure show two undertows,also a visible setup in the surf *** demonstrates the importance of the radiation stress in wave-induced currents and mean water levels（set-up/down）.

关键词： COHERENS-SED radiation stress wave-induced current setup

Newton-conjugate gradient (CG) augmented Lagrangian method for path constrained dynamic process optimization

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控制理论与应用（英文版） 2012年第2期10卷 223-228页

作者： Qiang ZHANG, Shurong LI, Yang LEI, Xiaodong ZHANG college of Information and Control engineering, china university of Petroleum (East china), qingdao Shandong 266555, china college of Information and Control engineering China University of Petroleum (East China) Qingdao Shandong China

In this paper, a Newton-conjugate gradient （CG） augmented Lagrangian method is proposed for solving the path constrained dynamic process optimization problems. The path constraints are simplified as a single final time constraint by using a novel constraint aggregation function. Then, a control vector parameterization （CVP） approach is applied to convert the constraints simplified dynamic optimization problem into a nonlinear programming （NLP） problem with inequality constraints. By constructing an augmented Lagrangian function, the inequality constraints are introduced into the augmented objective function, and a box constrained NLP problem is generated. Then, a linear search Newton-CG approach, also known as truncated Newton （TN） approach, is applied to solve the problem. By constructing the Hamiltonian functions of objective and constraint functions, two adjoint systems are generated to calculate the gradients which are needed in the process of NLP solution. Simulation examlales demonstrate the effectiveness of the algorithm.

关键词： Dynamic process optimization Constraint aggregation Augmented Lagrangian Newton-CG approach Adjoint formulation

The difference between the joint probability distributions of apparent wave heights and periods and individual wave heights and periods

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Acta oceanologica Sinica 2004年第3期23卷 399-406页

作者： ZHENGGuizhen JIANGXiulan HANShuzong LaboratoryofPhysicaloceanography ChinaOceanUniversityQingdao266003China qingdaoInstituteofArchitectureandengineering Qingdao266031China

The joint distribution of wave heights and periods of individual waves is usually approximated by the joint distribution of apparent wave heights and periods. However there is difference between them. This difference is addressed and the theoretical joint distributions of apparent wave heights and periods due to Longuet-Higgins and Sun are modified to give more reasonable representations of the joint distribution of wave heights and periods of individual waves. The modification has overcome an inherent drawback of these joint PDFs that the mean wave period is infinite. A comparison is made between the modified formulae and the field data of Goda, which shows that the new formulae consist with the measurement better than their original counterparts.

关键词： sea waves wave statistics wave height wave period

Study on the two and three-parameter working stability regions of 3Y-TZP suspension

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Science china(Technological Sciences) 2006年第5期49卷 547-568页

作者： CHEN Youqiang1, 2, ZHANG Xinni3, CHEN Sha’ou3 & QI Ping3 1. Department of Chemistry, qingdao university, qingdao 2.6071, china 2. Department of Chemistry, Tsinghua university, Beijing 100084, china 3. Department of Physics, qingdao university, qingdao 2.6071, china 1. Department of Chemistry Qingdao University Qingdao 266071 China 2. Department of Chemistry Tsinghua University Beijing 100084 China 3. Department of Physics Qingdao University Qingdao 266071 China

We determined the variation tendency of viscosity (η) at various solids load- ing (α) for 3Y-TZP suspension as a function of dispersant concentration (Cw) using vis- cosity measurement, measured the diameter of particles as a function of Cw in very dilute suspension using light scattering method, and obtained the surface features of the sedi- ment of suspension with different Cw using SEM. We also discussed the influence of the microstructure of adsorbed polymer layers on particles and their interactions in the dis- persing medium on the stability of suspension. Then two different stable states and two different unstable states for 3Y-TZP suspension were given. Accordingly, the (Cw, η), (Cw, α), and (α, η) two-parameter, and (Cw, α, η) three-parameter stability maps were con- structed. Based on the DLVO theory calculations, the dispersant concentration, particle distance (r), and interparticle potential energy (VT) maps with various solids loading for 3Y-TZP aqueous suspension were also constructed. In (Cw, r) two-parameter coordinate system, the stable motion region map for particles was established. The Cw, α, and VT,max (the highest potential energy) surface of the potential barrier map was obtained through calculation and simulation on the basis of the surfaces of Cw, r, VT maps introduced above. The (Cw, α) two-parameter stability map was then obtained from the Cw, α, VT,max map. The results showed that this theoretical map can qualitatively prove the experimentally obtained results—the existence of different dispersed states of particles in suspension system and the variation tendency of suspension stability with changing each parame- ter—were reasonable.

关键词： 3Y-TZP, suspension, stability, DLVO theory, interparticle potential energy.

On the general expressions of finite Hankel transform

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Science china(Physics,Mechanics & Astronomy) 2010年第11期53卷 2125-2130页

作者： JIANG Quan 1,2 & GAO CunFa 1 1 college of Aerospace engineering,Nanjing university of Aeronautics and Astronautics,Nanjing 210016,china 2 School of Civil engineering,Nantong university,Nantong 226019,china 1. college of Aerospace engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China2. School of Civil Engineering Nantong University Nantong 226019 China

The general expressions of finite Hankel transform are naturally deduced with the help of the property of Bessel *** equations in this paper can degenerate into three kinds of boundaries since all the coefficients in the boundary conditions are taken into *** results can be adopted in solving physics problems involving the finite Hankel transform.

关键词： hankel transform bessel function finite integral

Direct adaptive neural control for stabilization of nonlinear time-delay systems

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Science china(Information Sciences) 2010年第4期53卷 800-812页

作者： WANG Min1,2*, ZHANG SiYing2, CHEN Bing2 & LUO Fei2 1college of Automation, South china university of Technology, Guangzhou 510641, china 2Institute of Complexity Science, qingdao university, qingdao 2.6071, china 1. college of Automation South China University of Technology Guangzhou 510641 China2. Institute of Complexity Science Qingdao University Qingdao 266071 China

This paper is concerned with the problem of adaptive neural control for uncertain nonlinear strict-feedback time-delay systems with unknown virtual control coefficients. Radial basis function (RBF) neural networks are employed to directly approximate unknown virtual control signals, and then the adaptive neural control law is constructed by Lyapunov-Krasovskii functionals and backstepping. In order to avoid encountering a large number of adaptive parameters when using RBF neural networks as function approximators, an unknown constant, instead of unknown neural weights themselves, is employed as the estimated parameter. This technique makes only one adaptive parameter tuned online, thus significantly alleviating the burdensome computation. Meanwhile, some continuous functions are introduced to overcome the design difficulty originating from the use of one adaptive parameter. The proposed adaptive control guarantees the boundedness of all the signals in the closed-loop system. Simulation studies are presented to illustrate the effectiveness of the scheme.

关键词： nonlinear time-delay systems neural control adaptive control backstepping

Evaporative Condensers in Comfortable Air Conditioning System

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湖南大学学报（自然科学版） 2009年第S1期36卷 136-140页

作者： YIN Ying-de1,ZHU Dong-sheng1,DU Gui-mei2,LI Yuan-xi1,SUN He-jing1,LIU Qing-ming1(1.Key Lab of Enhancement Heat Transfer and Energy Conservation,the Ministry of Education,South china university of Technology,Guangzhou,Guangdong 510641,china 2.college of Civil engineering,Hunan university,Changsha,Hunan 410082,china) Key Lab. of Enhancement Heat Transfer and Energy Conservation South China University of Technology Guangzhou 510641 China college of Civil engineering Hunan University Changsha 410082 China

The operating theory of an evaporative condenser was *** difference between an evaporative condensing refrigeration system and a general refrigeration system was *** with the air-cooled and the water-cooled,the virtues of energy-conservation and water-conservation of evaporative condensers were *** questions existing in the application of evaporative condensers were pointed out,the corresponding solving methods were analyzed accordingly,and the development trend of evaporative condensing technique in mechanical refrigeration system field and the applied foreground of evaporative condensers in comfortable air conditioning were prospected.

关键词： evaporative condensers evaporative condensing refrigeration system general refrigeration system comfortable air conditioning system