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Global optimization of tool path for five-axis flank milling with a cylindrical cutter

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Science china(Technological Sciences) 2009年第8期52卷 2449-2459页

作者： DING Han1 & ZHU LiMin2.1 state key {2. of Digital Manufacturing Equipment and technology, Huazhong university of Science and technology, Wuhan 430074, china 2.School of Mechanical Engineering, Shanghai Jiao Tong university, Shanghai 2.02.0, china state key {2. of Digital Manufacturing Equipment and technology Huazhong University of Science and Technology Wuhan 430074 China School of Mechanical Engineering Shanghai Jiao Tong University Shanghai 200240 China

In this paper, optimum positioning of cylindrical cutter for five-axis flank milling of non-developable ruled surface is addressed from the perspective of surface approximation. Based on the developed interchangeability principle, global optimization of the five-axis tool path is modeled as approximation of the tool envelope surface to the data points on the design surface following the minimum zone criterion recommended by ANSI and ISO standards for tolerance evaluation. By using the signed point-to-surface distance function, tool path plannings for semi-finish and finish millings are formulated as two constrained optimization problems in a unified framework. Based on the second order Taylor approximation of the distance function, a sequential approximation algorithm along with a hierarchical algorithmic structure is developed for the optimization. Numerical examples are presented to confirm the validity of the proposed approach.

关键词： five-axis flank milling tool path optimization tool axis trajectory surface surface approximation distance function minimax optimization

Gas Absorption Enhancement of Carbon Dioxide into Ca(OH)_2.Slurries

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Transactions of tianjin university 2007年第6期13卷 423-427页

作者：卢素敏马友光朱春英沈树华 state key {2. of Chemical Engineering School of Chemical Engineering and TechnologyTianjin University

Chemical absorption of CO2.into aqueous slurries of Ca(OH)2.was studied in a stirred thermostatic reactor. The influence of solid loading and stirring speed on absorption rate were investigated experimentally, and the results show that the enhancement factor increases with particle content due to the increase of reactive particles in the gas-liquid interfacial region. The absorption process was controlled by the diffusion of gas molecules in slurry. The influence of stirring intensity on enhancement factor is an integration of gas-liquid and liquid-solid mass transfer variation. A novel prediction model of enhancement factors was proposed with the partition of interface into two various zones, and the prediction values by the presented model are in agreement with the experimental data.

关键词： enhancement factor gas absorption mass transfer theoretical model

Experimental study of gas-water elongated bubble flow during production logging

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Petroleum Science 2011年第2期8卷 157-162页

作者： Lu Jing Wu Xiling key laboratory of Earth Prospecting and Information {2. China University of Petroleum Beijing 102249 China state key {2. of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China

In order to improve the interpretation of production log data on gas-water elongated bubble （EB） flow in horizontal wells, a multi-phase flow simulation device was set up to conduct a series of measurement experiments using air and tap water as test media, which were measured using a real production logging tool （PLT） string at different deviations and in different mixed flow states. By understanding the characteristics and mechanisms of gas-water EB flow in transparent experimental boreholes during production logging, combined with an analysis of the production log response characteristics and experimental production logging flow pattern maps, a method for flow pattern identification relying on log responses and a drift-flux model were proposed for gas-water EB flow. This model, built upon experimental data of EB flow, reveals physical mechanisms of gas-water EB flow during measurement processing. The coefficients it contains are the specific values under experimental conditions and with the PLT string used in our experiments. These coefficients also reveal the interference with original downhole flow patterns by the PLT string. Due to the representativeness that our simulated flow experiments and PLT string possess, the model coefficients can be applied as empirical values of logging interpretation model parameters directly to real production logging data interpretation, when the measurement circumstances and PLT strings are similar.

关键词： Horizontal wells elongated bubble flow flow patterns identification drift-flux model,logging interpretation model

Adsorption and Insecticidal Activity of Toxin from Bacillus thuringiensis on Rectorite

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Pedosphere 2007年第4期17卷 513-521页

作者： ZHOU Xue-Yong HUANG Qiao-Yun CAI Peng YU Zi-Niu Hubei Province key laboratory of Refractories and Ceramics Wuhan University of Science and Technology Wuhan 430081 （China）. College of Biotechnology and Chemical Engineering Tianjin University of Technology Tianjin 300191 （China） state key {2. of Agricultural Microbiology College of Resources and Environment Huazhong Agricultural Uni- versity Wuhan 430070 （China）

The adsorption and desorption of the toxin from Bacillus thuringiensis strain WG-001 on rectorite were studied at different toxin and/or rectorite concentrations, pH values and temperatures. The insecticidal activity of the adsorbed toxin was evaluated by determining the lethal concentration to kill 50% of the larvae of Heliothis armigera （LC50）. The adsorption of the toxin on rectorite in sodium carbonate buffer （pH 9） reached equilibrium within 0.5-1.0 h and the adsorption isotherm of the toxin followed the Langmuir equation （R^2.〉 0.99）. In the pH range from 9 to 11 （carbonate buffer）, the adsorbed toxin decreased with increasing pH. The adsorption amounts decreased with increasing rectorite：toxin ratio. The adsorption was not significantly affected by the temperature between 10 and 50 ℃. The X- ray diffraction analysis indicated occurrence of the intercalation of the rectorite by the toxin. The infrared absorption spectrum showed that the binding of the toxin did not alter its structure. The LC50 wlues of the adsorbed toxin were smaller than those of the free toxin. The rectorite protected the toxin from ultraviolet irradiation damage. The desorption of the adsorbed toxin in water ranged from 37.5% to 56.4% and from 2..4% to 41.8% in a carbonate buffer. The desorption percentage also decreased with increasing rectorite：toxin ratio.

关键词： Bacillus thuringiensis insecticidul uctivity rectorite toxin udsorption und desorption

A NEW SYNERGIST FOR INTUMESCENT FLAME RETARDANT POLYPROPYLENE

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Chinese Journal of Polymer Science 2002年第4期20卷 377-380页

作者： Qiang Wu Bao-jun Qu state key {2. of Fire Science and Department of Polymer Science and Engineering university of Science and technology of china, Hefei 2.002. china Univ Sci & Technol china State Key Lab Fire Sci Hefei 230026 Peoples R China Univ Sci & Technol china Dept Polymer Sci & Engn Hefei 230026 Peoples R China

The synergistic effects of silicotungstic acid (SiW12. as a catalyst in the phosphorus-nitrogen compounds AM-based intumescent flame-retardant (IFR) polypropylene (PP) were studied using the limiting oxygen index (LOI), the UL-94 test, thermogravimetric analysis (TGA), real time Fourier transform infrared (FTIR), laser Raman spectroscopy (LRS). The LOI data show that SiW12.added to PP/IFR systems has a synergistic FR effect with an IFR additive named AM. The TGA data show that SiW12.apparently increases the thermal stability of the PP/IFR systems at high temperature (T > 500degreesC). The FTIR results provide the positive evidence that IFR can improve the thermal stability of PP and SiW12.can induce a higher rate of formation of phosphoric acid and its derivatives. The LRS measurements provide useful information on the carbonaceous microstructures. In short, a suitable amount of SiW12.(1.5 wt%) exerts synergistic effects with the IFR by increasing the LOI value and the thermal stability at high temperature and promoting the formation of charred structures on the burning PP surface.

关键词： silicotungistic acid synergistic effect intumescent flame retardant polypropylene

Structure Evolution of Bulk Metallic Glass Zr_(52.5)Ni_(14.6)Al_10Cu_(17.9)Ti_5 during Annealing

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Journal of Materials Science & technology 2000年第4期16卷 357-361页

作者： Guo HE, Zan BIAN and Guoliang CHEN (state key {2. of Advanced Metals and Materials, university of Science and technology Beijing,Beijing 100083, china) state key {2. of Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

Bulk metallic glass Zr_52.5Ni_14.6Al_10Cu_17.9Ti_5 was prepared by melt injection casting method. Its glass transition and crystallization temperatures were determined by differential scanning calorimetry (DSC) to be 631 K and 710 K respectively. By analysis of X-ray diffractometry (XRD) and transmission electron microscopy (TEM ), the predominant crystallized phase of Zr_2.i0.67O0.33 distributed on glass state matrix was detected after annealing at 673 K for 600 s. The transformation to Zr_2.i_0.67O_0.33 and a small amount of ZrAl and Zr_2.u took place after annealing for 600 s at temperature from 703 K to 72. K. With increasing annealing temperature from 753 K to 82. K, the amounts of ZrAl and Zr_2.u increased, but the size of the crystals did not significantly change. The transformation to Zr_2.i_0.67O_0.33 is interface-controlled, but is diffusion-controlled to Zr_2.u and ZrAl. With increasing annealing temperature up to 2.0 K above T_x, the nanometer grains became very fine because of the increase of nucleation rate for Zr_2.u and ZrAl.

关键词： Structure Evolution of Bulk Metallic Glass Zr Ti5 during Annealing Al10Cu Ni Cu

Adsorption of zinc on manganite(γ-MnOOH): particle concentration effect and adsorption reversibility

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Journal of Environmental Sciences 2004年第4期16卷 627-630页

作者： QIN Yan-wen1, PAN Gang 1,2., ZHANG Ming-ming1, LI Xian-liang1 (1. state key {2. of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, china. 2. Qingdao university of Science & technology, Qingdao 2.6042. china) state key {2. of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China.

The adsorption and desorption processes of Zn(Ⅱ) on γ-MnOOH as a function of particle concentrations(C p) were studied. An obvious C p effect was observed in this adsorption system. The degree of adsorption hysteresis increased greatly with the increasing of C p, indicating that the extent of the real metastable-equilibrium states deviating from the ideal equilibrium state was enhanced with the increasing of C p. The C p-reversibility relationship confirmed the metastable-equilibrium adsorption(MEA) inequality(Pan, 1998a), which was the core formulation of the MEA theory. Because the MEA inequality was based on the basic hypothesis of MEA theory that adsorption density Γ is not a state variable, the C p-reversibility relationship gave indirect evidence to the basic hypothesis of MEA theory.

关键词： zinc γ-MnOOH adsorption reversibility

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 key {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.

Fabrication and Characterization of Nano Silver Powder Prepared by Spray Pyrolysis

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Journal of Wuhan university of technology(Materials Science) 2009年第6期24卷 871-874页

作者：章桥新 School of Mechanical and Electronic Engineering Wuhan University of Technology state key {2. of Advanced technology for Materials Synthesis & Processing Wuhan University of Technology

Silver powder was fabricated by spray pyrolysis, using 2.-2.% AgNO3 solution, 336-500 mL/h flux of AgNO3 solution, 0.2.-0.32.MPa flux of carrier gas and in the 62.-82. ℃ temperature range. The effects of furnace set temperature, concentration of AgNO3 aqueous solution, flux of AgNO3 aqueous solution as well as carrier gas on the morphology and particle size distribution of silver powder, were investigated. The experimental results showed that with the high concentration of AgNO3 aqueous solution, the average grain size of silver decreased with the increasing of furnace set temperature. But the gain size distribution was not homogenous, the discontinuous grain growth occurred. With the low concentration of AgNO3 aqueous solution, the higher furnace set temperature made the nano sliver grains sintered together to grow. Nano silver powder about 100 nm was fabricated by spray pyrolysis, using 2.t% AgNO3 solutions, 336 mL/h flux of AgNO3 aqueous solution, 0.32.MPa flux of carrier gas at 72. ℃ furnace set temperature.

关键词： nano silver powder fabrication characterization spray pyrolysis