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A simple lattice Boltzmann scheme for low Mach number reactive flows

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Science china(Technological Sciences) 2006年第6期49卷 714-726页

作者： CHEN Sheng1,2. LIU Zhaohui2. ZHANG Chao2. HE Zhu2. TIAN Zhiwei2. SHI Baochang 2.& ZHENG Chuguang2.1. technology Center of wuhan Iron and Steel (Group) Company, wuhan 430080, china 2. state key laboratory of coal combustion, Hua Zhong University of Science and technology, wuhan 430074, china technology Center of {1. Iron Steel [Group] Company Wuhan 430080 China state {1. {2. of coal combustion Hua Zhong University of Science technology Wuhan 430074 China

For simulating low Mach number reactive flows, a simple and coupled lattice Boltzmann (CLB) scheme is proposed, by which the fluid density can bear significant changes. Different from the existing hybrid lattice Boltzmann (HLB) scheme and non-coupled lattice Boltzmann (NCLB) scheme, this scheme is strictly lattice Boltzmann style and the fluid density couples directly with the temperature. Because it has got rid of the constraint of traditional thought in lattice Boltzmann scheme,on the basis of the equality among the particle speed c, the time step △t and the lattice grid spacing △x held, both c and △t can be adjusted in this scheme according to a "characteristic temperature" instead of the local temperature. The whole algorithm becomes more stable and efficient besides inheriting the intrinsically outstanding strong points of conventional lattice Boltz-mann scheme. In this scheme, we also take into account different molecular weights of species, so it is more suitable for simulating actual low Mach number reactive flows than previous work. In this paper, we simulated a so-called "counter-flow" premixed propane-air flame, and the results got by our scheme are much better than that obtained by NCLB. And the more important thing is that the exploration in this work has offered a kind of brand-new train of thought for building other novel lattice Boltzmann scheme in the future.

关键词： lattice Boltzmann, low Mach number flows, reactive flows, simulation.

Element geochemistry and cleaning potential of the No. 1. coal seam from Antaibao mining district

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Science china Earth Sciences 2005年第12期48卷 2142-2154页

作者： WANG Wenfeng1. QIN Yong1. SONG Dangyu2. SANG Shuxun1. JIANG Bo1. ZHU Yanming1.& FU Xuehai1.1. College of Resources & Geosciences,{1. University of Mining and technology, Xuzhou 2.1.08,{1. 2. state key laboratory of coal combustion, huazhong University of Science and technology, wuhan 430074,{1. 1. College of Resources & Geosciences China University of Mining and Technology 221008 Xuzhou China 2. state key laboratory of coal combustion Huazhong University of Science and Technology 430074 Wuhan China

Based on the analyses of sulfur and 41.other elements in 8 channel samples of the No. 1. coal seam from Antaibao surface mine, Shanxi,{1. and 4 samples from the coal preparation plant of this mine, the distribution of the elements in the seam profile, their geo-chemical partitioning behavior during the coal cleaning and the genetic relationships between the both are studied. The conclusions are drawn as follows. The coal-forming environment was probably invaded by sea water during the post-stage of peatification, which results in the fact that the contents of As, Fe, S, etc. associated closely with sea water tend to increase toward the top of the seam, and that the kaolinite changes into illite and montmorillonite in the coal-sublayer near the roof. These elements studied are dominantly associated with kaolinite, pyrite, illite, montmorillonite, etc., of which the As, Pb, Mn, Cs, Co, Ni, etc. are mainly associated with sulfides, the Mo, V, Nb, Hf, REEs, Ta etc. mainly with kaolintie, the Mg, Al etc. mainly with epigenetic montmorillonite, and the Rb, Cr, Ba, Cu, K, Hg, etc. mainly with epigenetic illite. The physical coal cleaning is not only effective in the removal of ash and sulfur, but also in reducing the concentra-tion of most major and trace elements. The elements Be, U, Sb, W, Br, Se, P, etc. are largely or partly organically bound showing a relatively low removability, while the removability of the other elements studied is more than 2.%, of which the Mg, Mn, Hg, Fe, As, K, Al, Cs, and Cr associ-ated mostly with the coarser or epigenetic minerals show a higher removability than that of ash. The distribution of the elements in the seam profile controls their partitioning behavior to a great degree during the coal cleaning processes.

关键词： Antaibao mining district, No.1. coal seam, element geochemistry, cleaning.

Technical-economic evaluation of O_2.CO_2.recycle combustion power plant based on life-cycle

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Science china(Technological Sciences) 2010年第12期53卷 3284-3293页

作者： WANG Yun, ZHAO YongChun, ZHANG JunYing & ZHENG ChuGuang state {1. {2. of coal combustion, huazhong University of Science and technology, wuhan 430074, china 1. state {1. {2. of coal combustion Huazhong University of Science and Technology Wuhan 430074 China

In this study, a detailed technical-economic analysis on a O2.CO2.recycle combustion power plant (Oxy-combustion plant) retrofitted from the existing {2.-fired plant (with a capacity of 2.300 MW) in china was carried out by using life cycle assessment (LCA) and life cycle cost (LCC) method. The CO2.emissions, investment cost, cost of electricity and CO2.avoidance cost within the life cycle were calculated respectively. The results showed that the CO2.emission avoidance rate of retrofitted Oxy-combustion plant in the life cycle was about 77.09% without taking account of the CO2.compression; the annual cost increased by 5.9% approximately, the net power decreased by 2..33%, the cost of electricity increased by 34.77%, and the CO2.avoidance cost was about 2..93 USD/t. Considering the compression process of CO2. the avoidance rate of CO2.emission was about 73.35% or so; the annual cost increased by 9.35% approximately, the net power decreased by about 2..70%, the cost of electricity increased by 49.1.%, and the CO2.avoidance cost was about 45.46 USD/t. The carbon tax (the CO2.tax) should be more than about 2. USD/t and 34 USD/t under the condition of considering CO2.compression or not, respectively, which is beneficial to promote transformation of existing {2.-fired plant for reducing the CO2.emissions.

关键词： life cycle assessment coal-fired power plant O2.CO2 recycle combustion technology cost of electricity CO2 avoidance cost

Review of soot measurement in hydrocarbon-air flames

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Science china(Technological Sciences) 2010年第8期53卷 2129-2141页

作者： LOU Chun,CHEN Chen,SUN YiPeng&ZHOU HuaiChun state {1. {2. of coal combustion,huazhong University of Science and technology,wuhan 430074,china 1. state {1. {2. of coal combustion Huazhong University of Science and Technology Wuhan 430074 China

Soot,which is produced in fuel-rich parts of flames as a result of incomplete combustion of hydrocarbons,is the No.{1.contributor to global warming after carbon *** soot measurement techniques is important to understand soot formation mechanism and control soot *** various soot measurement techniques,such as thermophoretic sampling par-ticles diagnostics followed by electron microscopy analysis,thermocouple particle densitometry,light extinction,laser-induced incandescence,two-color method,and emission computed tomography,are reviewed in this *** measurement principle and application cases of these measurement methods are described in *** development trend of soot measurement is to realize the on-line measurement of multi-dimensional distributions of temperature,soot volume fraction,soot particle size and other parameters in hydrocarbon-air *** measurement techniques suitable for both small flames in laboratories and large-scale flames in industrial combustion devices should be ***,in some special situations,such as high-pressure,zero gravity and micro-gravity flames,soot measurement also should be provided.

关键词： hydrocarbon-air flames combustion measurement soot laser-induced incandescence emission CT

Exact eigenstates for a class of models describing multiphoton processes in the presence of seven bosonic modes

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Science china(Physics,Mechanics & Astronomy) 2004年第6期47卷 649-657页

作者： ZHAN Zhiming1,LI Weibin2.YOU Jun2.XIE Xiaotao2.& YANG Wenxing2.1.state key {2. of Laser technology,huazhong University of Science and technology,wuhan 430074,china 2.Department of Physics,huazhong University of Science and technology,wuhan 430074,china 1. state {1. {2. of Laser technology Huazhong University of Science and Technology 430074 Wuhan China 2. Department of Physics Huazhong University of Science and Technology 430074 Wuhan China

We present the analytical expressions of eigenstates and eigenenergies by using a parameter λ without the assumption of Bethe anzatz for three kinds of seven-bosonic-mode mixing models. The parameter is shown to be determined by the roots of a simple polynomial. We also demonstrate the exact analytical expressions of eigenstates and energies without any unknown parameter.

关键词： spectra, eigenstate, eigenvalue.

Exsolution of ilmenite and Cr-Ti magnetite from olivine of garnet-wehrlite

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Science china Earth Sciences 2005年第9期48卷 1368-1376页

作者： LIU Xiangwen1.2. JIN Zhenmin1.3, QU Jing2.& WANG Lu2.1. state key {2. of Geological Processes and Mineral Resources, china University of Geosciences, wuhan 430074, china 2. Graduate School of china University of Geosciences, wuhan 430074, china 3. Faculty of Earth Sciences, china University of Geosciences, wuhan 430074, china 1. state {1. {2. of Geological Processes and Mineral Resources China University of Geosciences 430074 Wuhan China 2. Graduate School of{1. University of Geosciences 430074 Wuhan China 3. Faculty of Earth Sciences China University of Geosciences 430074 Wuhan China

Exsolution of rod-like ilmenite (Ilm) and Cr-Ti magnetite (Mt) have been found in olivine of garnet-wehrlite from the core of Chinese Continental Sciences Drilling (CCSD). Their composition, morphology, crystal structure and their topotaxies with host olivine have been studied in detail by the transmission electron microscopy (TEM) and electron probe microanaly- sis (EPMA) technique. It shows that rod-like Ilm exsolution reported in this paper has similar characteristic with that of Alpe Arami olivine, while Cr-Ti magnetite exsolution mentioned in this paper has large discrepancy with chromite exsolution in Alpe Arami olivine. These observations suggest that both of the exsolutions found in this paper should be solid solution phases in β-olivine at their first period, then experiencing decomposition of solid solution and therefore forming Ilm and Cr-Ti magnetite exsolution with the pressure decreasing. So, this garnet-wehrlite perhaps had been ever located in mantle transition zone with a minimum depth of 300 km.

关键词： garnet-wehrlite, ilmenite, magnetite, exsolution, CCSD.

Calculation of maximum ground movement and deformation caused by mining

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中国有色金属学会会刊：英文版 2011年第S3期21卷 562-569页

作者： LI Pei-xian1. 2. TAN Zhi-xiang1. 2. DENG Ka-zhong1. 2.1. key laboratory for Land Environment and Disaster Monitoring of {2. Bureau of Surveying and Mapping, china University of Mining and technology, Xuzhou 2.1.1., china 2. Jiangsu key laboratory of Resources and Environmental Information Engineering, china University of Mining and technology, Xuzhou 2.1.1., china [a] key {1. for Land Environment and Disaster Monitoring of {2. Bureau of Surveying and Mapping China University of Mining and Technology Xuzhou 221116 China [b] Jiangsu key {1. of Resources and Environmental Information Engineering China University of Mining and Technology Xuzhou 221116 China

In order to know the maximum mining ground deformation of arbitrary surface point, directions of the maximum surface tilt, curvature,horizontal displacement and horizontal deformation caused by multi-working faces were deduced based on probability integral method. The distribution forms of surface deformations in all direction φ∈[0, 2.] were obtained and also equations of maximum deformations were given based on calculation of mining ground deformation in direction φ. A mining subsidence analysis system was developed with VB6.0. The system implements the probability integral mining subsidence prediction with direct integration method, and it can avoid errors of arbitrary shaped working face subdivision of traditional method, and accuracy of mining subsidence prediction can be improved with the direct integral method. The system implements the contour chart and profile chart and also data analysis automation by manipulation of the SURFER kernel function and it complements the defect of existing subsidence prediction software. Calculation of maximum deformations caused by multi-working faces mining in a {1. mine of Xuzhou, china was shown as application example. Engineering application indicates that maximum deformation of mining ground surface can be calculated and analyzed by the system. The research provides a theoretical basis and calculation tool for mining subsidence prediction and analysis.

关键词： mining subsidence probability integral method movement and deformation system development

Density functional theory study of the reaction paths of reactions of CH3C（O）O2.radicals with HO2.in the gas phase

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Progress in Natural Science:Materials International 2006年第12期16卷 1269-1274页

作者： ZHOU Yuzhi~ 1.2., ZHANG Shaowen~1.and LI Qianshu~1.*(1. {1. key {2. of Explosion Science and technology, Beijing Institute of technology, Beijing 1.0081. china 2. Beijing Institute of Education, Beijing 1.0044, china) [a]state {1. {2. of Explosion Science and technology Beijing Institute of Technology Beijing China [b]Beijing Institute of Education Beijing China

A DFT study on the reactions between CH_3C（O）O_2.nd HO_2.adicals has been carried out. It is suggested that both the triplet and singlet potential surfaces involve a complex mechanism with the formation of loosely bound intermediate complexes of reactants and products. The reaction prefers to occur on the triplet surface to produce peracetic acid (CH_3C（O）O_2.) and triplet O_2.olecule. The CH_3C（O）O_2. can further convert into CH_3C（O）O and HO radicals.

关键词： acetyl peroxy radicals HO2.radicals reaction mechanism DFT.

Third-order point contact approach for five-axis sculptured surface machining using non-ball-end tools (Ⅰ): Third-order approximation of tool envelope surface

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Science china(Technological Sciences) 2010年第8期53卷 1904-1912页

作者： ZHU LiMin1, DING Han2.& XIONG YouLun2.1 state key {2. of Mechanical System and Vibration, Shanghai Jiao Tong University, Shanghai 2.02.0, china 2.state key {2. of Digital Manufacturing Equipment and technology, huazhong University of Science and technology, wuhan 430074, china 1. state {1. {2. of Mechanical System and Vibration Shanghai Jiao Tong University Shanghai 200240 China2. State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and Technology Wuhan 430074 China

In this paper, the geometric properties of a pair of line contact surfaces are investigated. Then, based on the observation that the cutter envelope surface contacts with the cutter surface and design surface along the characteristic curve and cutter contact (CC) path, respectively, a mathematical model describing the third-order approximation of the cutter envelope surface according to just one given cutter location (CL) is developed. It is shown that at the CC point both the normal curvature of the normal section of the cutter envelope surface and its derivative with respect to the arc length of the normal section can be determined by those of the cutter surface and design surface. This model characterizes the intrinsic relationship among the cutter surface, cutter envelope surface and design surface in the neighborhood of the CC point, and yields the mathematical foundation for optimally approximating the cutter envelope surface to the design surface by adjusting the cutter location.

关键词： five-axis NC machining rotary cutter cutter envelope surface normal curvature third-order point contact

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