Catalytic Synthesis of Butyl Acetate by Bismuth Phosphotungstate
LAI Jun-ling, WANG Jing, LUO Gen-xiang, ZHANG Shao-hua
2012, 32 (4): 1-3.
Abstract ( ) PDF ( 440KB ) ( ) 　　
The catalyst bismuth phosphotungstate was prepared and characterized by XRD and TGA, then its catalytic performance was evaluated with the esterification of n-butanol and acetic acid. The effect of different phosphotungstates, molar ratio of acid to alcohol, the catalyst amount and reaction time on catalytic performance were investigated. The experiment results show that the yield of esterification can reach 92.4% under the following conditions: molar ratio of acid to alcohol 1∶1.5, catalysts amount 8wt% (based on acetic acid), reaction time 45 min under reflux.
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The Desulfurization & Denitrification of Coker Gasoline by Heteropoly Acid
LI Yun，WANG Xiang-fu，GUO Da-guang, JI Cheng-cheng，YAN Feng，XU Yao-hui
2012, 32 (4): 4-7.
Abstract ( ) PDF ( 605KB ) ( ) 　　
The oxidation desulfurization and denitrification of coker gasoline were carried out with hydrogen peroxide as the oxidant, phosphorus tungsten acid as catalyst, cetyl trimethyl ammonium chloride as phase transfer catalysts and furfural as extracting agent. The desulfurization and denitrification rate can reach to 89.93% and 95.10% under the following conditions: gasoline 50 mL, catalyst 0.32 g, phase transfer catalyst 0.09 g, hydrogen peroxide 5 mL, oxidation temperature 70 ℃, oxidation time 60 min. The Oxidant Solution can be recycled when replenishing appropriate oxidant and phase transfer catalysts, and the extractant can also be recycled after treatment. Without phase transfer catalyst, the desulphurization and denitrification rate were only 77.35% and 91.98%, respectively. Therefore, phase transfer catalyst can greatly improve the desulfurization performance.
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Evaluation of Uncertainty in the Determination of  Calcium and Magnesium in Milk by MPT-AES
YU Yong-qing, ZHANG Jin-sheng, LI Li-hua, ZHAO Wen-tao, 
2012, 32 (4): 8-12.
Abstract ( ) PDF ( 594KB ) ( ) 　　
The measurement uncertainty was estimated for the determination of calcium and magnesium in milk using microwave plasma torch atomic emission spectrometry (MPT-AES) and the uncertainty parameters were discussed and compared in detail. The results show that the "whole method" performance parameters, such as precision and recovery, and sampling are the three main contributors to uncertainty. In addition, the content of calibration solution is the main contributor to measurement uncertainty in the determination of magnesium. When coverage factor k=2 and confidence level approximately 95%, the expanded uncertainties were determined as 18.6 and 3.2 mg/L for Ca and Mg, respectively.
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Hydrolysis of Corn Straw to Produce Reducing Sugar by Diluted Acid Over Ferrous Sulfate Under Microwave Radiation
ZHANG Jin-hui, WANG Shuo, ZHANG Qi-kai, LI Fei, DU Yun-chao
2012, 32 (4): 13-16.
Abstract ( ) PDF ( 718KB ) ( ) 　　
The corn straw was hydrolyzed by diluted acid via microwave radiation under the conditions of the metal salt ferrous sulfate as catalyst. The effect on the reducing sugar production rate was investigated by the concentration of ferrous sulfate, sulfuric acid content, ratio of liquid to solid, the microwave radiation power, time and pressure. The results show that the product yield can reach 38.5% under the best hydrolysis conditions: ferrous sulfate mass fraction of 3%, sulfuric acid mass fraction of 2%, mass ratio of liquid to solid 15, the microwave radiation power 187.5 W, the microwave radiation time 30 min and the microwave radiation pressure 0.3 MPa. Compared to the method without ferrous sulfate or without microwave radiation, this method shows higher yields by 1.1 and 2.8 times, respectively. 
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Adsorption Desulfurization With Nb/SBA-15 Molecular Sieve
ZHAO Ming-fei, SHEN Jian, WANG Lei, NIE Ning, LI Shao-kai
2012, 32 (4): 17-20.
Abstract ( ) PDF ( 698KB ) ( ) 　　
Niobic acid/SBA-15 molecular sieve was prepared by impregnation method, and characterized by XRD and BET. The results show specific surface area, pore volume and pore diameters of the sample slightly decreased; however, mesoporous structure was well preserved. Its desulfurization performance from model oil was studied by static adsorption method. The results show that the sulfur removal rate can reach 31.30% and saturation adsorption capacity was 599 μg/g under the following optimum conditions: niobic acid/support 10wt%, adsorption temperature 120 ℃, time 30 min and catalyst/oil weight ratio 1∶20.
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Preparation of Oxidized Wax Emulsion
CHEN Peng，Liu Shu-xin, JI Ling-xian，WANG De， CONG Yu-feng， HUANG Wei1
2012, 32 (4): 21-23.
Abstract ( ) PDF ( 627KB ) ( ) 　　
Self-made oxidized wax was adopted to develop oxidized wax emulsion in this experiment, and the effect of emulsifiers amount, emulsification temperature, stirring speed and emulsification time on emulsion performance were investigated, and finally the formulation of complex emulsifiers and the emulsification technology were determined. The results show that the first grade oxidized wax emulsion, which is milk white and has good stability and dispersity, can be prepared when the HLB value of surfactants is 12.0, reaction temperature is 85 ℃, stirring speed is 800 r/min and reaction time is 35 min
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Synthesis of Cyclohexyl Acetate Catalyzed by Y-β Composite Zeolite Supported Phosphotungstic Acid
LIU Chun-sheng， LUO Gen-xiang
2012, 32 (4): 24-27.
Abstract ( ) PDF ( 736KB ) ( ) 　　
This manuscript reported the acylation of cyclohexanol with acetic anhydride catalyzed by Y-β composite zeolite supported phosphotungstic acid（H3PW12O40/Y-β）. The effect of different factors such as the amount of catalyst，the ratio of cyclohexanol to acetic anhydride and reaction time on the yield of cyclohexyl acetate were systematically studied. The results show that Y-β composite zeolite supported phosphotungstic acid has a good catalytic activity. The best of reaction condition is found out as follows: the amount of acetic anhydride is 0.1 mol, the ratio of cyclohexanol to acetic anhydride is 1.1, and the catalyst is 0.60 g. The yield of cyclohexyl acetate reached 93.4% within 45 min. The catalyst can be repeatedly used for 5 times without obvious loss of its activity. The product was characterized by refractive index and IR.
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Application of Solar Energy in Pulverized Coal Boiler
WANG Chun-hua，LI Meng-hao，XU Le-le，LIU Xiao-qiu，HAN Chang-ming，LIANG Yuan
2012, 32 (4): 28-32.
Abstract ( ) PDF ( 952KB ) ( ) 　　
Through conducting numerical simulation on the combustion and heat transfer process of the boiler, under the conditions of the different temperature the temperature distribution and volume fraction distribution of the pollutant in the combustion chamber were predicted. The results show that when the furnace temperature met the production requirement if the secondary and tertiary air is preheated to a high-temperature, the total amount of air and coal are both reduced. Meanwhile, the amount of the pollutants could be reduced to achieve the purpose of energy-saving and emissions-reduction. As the increasing air temperature, the furnace temperature at the same section is more uniformity, thus the water wall tube would be heated uniformly, which is helpful for water cycle stability in boiler.Therefore, combustion technology of high temperature and low oxygen could be used in the pulverized coal boiler. To reach high-temperature air, a solar air-heater should be installed on boilers tail to utilize solar energy to assist the flue gas waste heat to heat the secondary and tertiary air to 873 K above.
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Simulation of Temperature Field With Hot  Oil Leak in the Soil of Different Particle
SHI Jun-jie， WANG Yue，MA Yue， CAO Yan-long， DAI Kan-liang
2012, 32 (4): 33-36.
Abstract ( ) PDF ( 978KB ) ( ) 　　
For the problem of oil leak in different soil particle diameter, using CFD simulation software to establish the soil porous media mid-stream solid coupled mathematical model of phase transitions. The simulation results show that before the leaking, the distribution of isotherms of the steady-state temperature field becomes the sharp of flat circle and the temperature lower from inside to outside. Meanwhile, this distribution does not have obvious changes in the different sizes of soil particles; after the leaking, the isothermal lines in the small particle diameter soil presented divergent patterns with reduction of the distribution from inside to outside. At the same time, with the leakage of oil flowing into the porous medium, the temperature gradient tended to be stable. In large particles soil, because of the low power of oil flow resistance, the change of water which exit in permafrost could happen faster, and the stochastic distribution of the isotherms of the divergent is more obvious. This situation destructed the stable temperature field more seriously.
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Analysis of Influence of Viscosity Difference on Contaminated Oil Quantity in Batch Pipelining
WANG Yue，MA Yue，ZHANG Guo-jun，SUN Xian-hang，SONG Shi-xiang，FAN Kai-feng
2012, 32 (4): 37-40.
Abstract ( ) PDF ( 1027KB ) ( ) 　　
 
A three-dimensional coupled flow model was built by CFD software. The model serviced the problem of contaminated oil between two viscosity types of down diesels and one type of forward gasoline in batch pipelining. The calculation results of simulation showed that the viscosity difference from the forward to the last oil dramatically affected the contaminated volume aside in the switching process. The change of lateral contaminated section under two different viscosity could be showed. In the earlier contamination, the down diesel will insert in forward oil by bowing forward surface. After 30 seconds, the bowing forward surface became sharp and stretch to the forward in conical surface. In longitudinal contaminated cross-section, the diesel inserted to the forward oil from the lower part of the pipeline by wedge-shaped striker surface. The contaminated volume decreased with the increase of viscosity difference in side, top and bottom area. The contaminated volume is maximum at the bottom boundary area.
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Analysis on Liquefaction Station Along Long-Distance LNG Pipeline
LI Zheng-bo，CHEN Bao-dong*，LIU Jie，GUAN Xue-yuan，MO Hai-yuan， ZHANG Chun-jing，DU Yi-peng
2012, 32 (4): 41-44.
Abstract ( ) PDF ( 823KB ) ( ) 　　
 
As the declining of oil, coal and other fossil fuel, and the rising of environmental pollution and greenhouse's effect, natural gas, as a kind of high efficient and clean energy, has been given a great attention and favour by the countries all over the world. Natural gas liquefaction and storage technology is key to its use and development. The latest theory research shows that the construction of long distance LNG pipeline is feasible in technology and reasonable in the economy. However the researches of the liquefaction station of long distance LNG pipeline are few. The liquefaction process of the liquefaction station along the long distance LNG pipelines was discussed. Through the analysis on the reverse Carnot cycle, combined with cooling characteristics of refrigerant such as propane, ethylene, methane, liquefaction process of liquefaction station along long-distance LNG pipeline was proposed and related equipments were selected.
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Application of MATLAB PDE Toolbox in the First Problem of Stokes
ZHANG Chun-jing，SHEN Long-she，JI Fu-qiang，YU Li-li
2012, 32 (4): 45-47.
Abstract ( ) PDF ( 888KB ) ( ) 　　
 
The first problem of stokes is a kind of common problem in the industrial production field. Traditional similar solution to the first problem of stokes is abstract and beyond understanding. Matlab PDE toolbox can vividly describe the first problem of stokes , output the concrete numerical value of research and vividly show the motion state of some plane. Matlab PDE toolbox provide an intuitive, quick, accurate and vivid numerical solution for the research of viscous flow of outside pipe's fluid medium.
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Calculation of the Economic Thickness on Insulation Layer for Overhead Steam Pipeline by List Method
DU Yi-peng， WANG Wei-min，et al
2012, 32 (4): 48-51.
Abstract ( ) PDF ( 799KB ) ( ) 　　
 
Through the calculation of all the expenses for insulation layer and the list analysis, the thickness of insulation layer corresponding to the minimum total cost was found.        Therefore the economic thickness was obtained to achieve the purpose of saving energy. The calculation results showed that the new method can scientifically reflect the relationship between the annual total cost and the thickness of insulation layer. And the method is straightforward and improve the design efficiency and quality greatly.
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Prediction of Safe Shutdown Time of Oil Pipeline Based on RBF Neural Network
GAO Yan-bo， MA Gui-yang，LIU Hong-yu，YAO Yao，WANG Lei，DAI Kan-liang
2012, 32 (4): 52-54. DOI:10.3696/j.issn.1672-6952.2012.04.014
Abstract ( ) PDF ( 881KB ) ( ) 　　
 
Considering the difficulty in the estimation of safe shutdown time of oil pipeline due to the complex safe shutdown of submarine oil pipeline influencing factors, the radial basis function neural network model was proposed for predicting safe shutdown time of submarine oil pipeline and the various influence factors on safe shutdown of oil pipeline were analyzed. The model was validated on the basis of actual data and the network was trained and the accuracy was verified. The results show that the fitting and simulation precision for training and testing samples is 98.40% and 97.33%, respectively. So the safe shutdown time of submarine oil pipeline can be predicted validly, and the important basis of safe transportation of submarine oil pipeline was provided.
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Influence of Insulation Failure Ratio on Safe Shutdown Time for the Hot Oil Pipeline
WANG Lei，WU Ming，JIA Feng-rui，YAO Yao， MA Yue，JIN Dun，FENG Jin-ye
2012, 32 (4): 55-59. DOI:10.3696/j.issn.1672-6952.2012.04.015
Abstract ( ) PDF ( 1006KB ) ( ) 　　
 
According to the problem of uncontrollable safe shutdown time when the insulation layer was partial failure under the specific conditions, a two-dimension, unsteady-state model of hot oil pipe was established by the finite volume method. In the model the influence of the latent heat of solidification was considered and the law of temperature drop in the hot oil pipe was compared and analyzed in five cases (i.e. no insulation failure, 1/8 insulation failure, 1/4 insulation failure, 1/2 insulation failure and complete insulation failure). Based on the above, the relative curve between the shutdown time and the average temperature of hot oil after line turndown was fitted by SPSS 18.0, and the safe shutdown time of the above five cases were determined finally. The results show that the laws of temperature drop of hot oil pipe is similar in the above five cases, and the safe shutdown time is 205, 148, 118, 99 and 74 hours. Due to the latent heat of solidification could partly make up for the heat loss, safe shutdown time of 1/2 insulation failure was only 19 hours less than 1/4 insulation failure’s.
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Ailure Analysis of Reformer Tube
LIANG Yan, MA Chao, JIANG Wen-quan
2012, 32 (4): 60-63. DOI:10.3696/j.issn.1672-6952.2012.04.016
Abstract ( ) PDF ( 1038KB ) ( ) 　　
 
The reformer furnace tubes have cracked after operating for in a service period in one plant, which lead to much economic losses. Therefore, it is necessary for us to carry on the over analysis of the reformer furnace tubes. The reformer furnace tubes were analyzed by using chemical composition analysis, macro-and micro-microstructure analysis, room temperature, high temperature mechanical properties analysis in the paper. The results show that the reason of failure for the furnace tube is the creep crack, and excess temperature is the direct reason for the creep crack. At the same time, the lack of the effect thickness in original design is the root cause of crack for the furnace tube.
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HHRT-GAP-tree in Multi-Scale Display Application
TAI Ying-ying, JIANG Shi-hua
2012, 32 (4): 64-67. DOI:10.3696/j.issn.1672-6952.2012.04.017
Abstract ( ) PDF ( 993KB ) ( ) 　　
 
In order to implement the multi-scale display of massive map data, a new algorithm based on HH-GAP-tree index was proposed, and topo operators were brought in this algorithm. First，the number of the scales was confirmed, multi-level Hilbert-R-tree index was built according to the scale, and inquiring data was located in a query window. Second, the GAP-tree index was built for the data, and the data was processed by topological operators. Last, the new data was dynamically generated. The experiments results show that this algorithm is available in multi-scale display, and the shortcomings of either of index are avoided.
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Simulation and Analysis on the Virtual Prototype of the Small Hydraulic Excavator
LI Na, DENG Zi-long, WANG Hong-yu, MAO Jia, CHEN Fang
2012, 32 (4): 68-71. DOI:10.3696/j.issn.1672-6952.2012.04.018
Abstract ( ) PDF ( 992KB ) ( ) 　　
 
The software PRO/E was adopted to create 3D solid model of the hydraulic excavator work device. Then established the virtual prototype after added restrictions by which the model imported to the software of ADAMS. The force curves of several main articulated points were obtained through the dynamics simulation by which the step function of the cylinder displacement, the step function of the force of the bucket tooth tip, the step function of the material gravity was caculated. The results has provided the basis for the strength analysis and structural optimization of the hydraulic excavator working device. The simulation test for the bucket arm cylinder of virtual prototype maximum digging force was accomplished by utilizing the principle of analog dynamometer. Then calculate the bucket arm cylinder maximum digging force, and the comparative analysis between the calculation results and the simulation results was completed. The research has provided the new avenue for the test of the excavator digging force.
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Data Processing Function About Parameter Drawing Based on AutoLISP
WANG Sheng-zhi， LAN Xiao-min
2012, 32 (4): 72-75. DOI:10.3696/j.issn.1672-6952.2012.04.019
Abstract ( ) PDF ( 848KB ) ( ) 　　
 
The data structure for parameter design and drawing program by AutoLISP in AutoCAD was discussed. The mode for data reading and writing in AutoLISP was analysed. The reading and writing data processing function all-purpose has been written by AutoLISP, and illustrate by examples. Afforded reference for parameter design and drawing program use AutoLISP in AutoCAD.
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An Improved Twin Support Vector Machine
DING Sheng-feng
2012, 32 (4): 76-79. DOI:10.3696/j.issn.1672-6952.2012.04.020
Abstract ( ) PDF ( 957KB ) ( ) 　　
 
As a new version of support vector machine(SVM),twin support vector machine(TWSVM) was proposed recently. TWSVM is not only faster than a conventional SVM, but shows good generalization for pattern classification. But the different effects of the different training samples on the classification hyperplanes are ignored in TWSVM, and the limitation is existed for some actual applications. Therefore, a twin support vector machine based on fuzzy membership was presented. A fuzzy membership function based on distance was designed, and TWSVM was modified by applying the fuzzy membership to every training sample, finally two optimal nonparallel hyperplanes were builded to achieve classification. The experiment results indicate that the classification performance of the algorithm is more superiorer than a traditional TWSVM.
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Calculation of Stress Intensity Factor for Fast-Opening Blind
GONG Xue， XIE Yu-jun, LIU Fu-min
2012, 32 (4): 80-82. DOI:10.3696/j.issn.1672-6952.2012.04.021
Abstract ( ) PDF ( 941KB ) ( ) 　　
 
In the engineering practice there is a lot of fracture phenomenon in the petroleum and chemical industry equipment. Fracture mechanics of linear elasticity fracture theory was involved. Through the analysis of the work principle of quick opening blind, simplify the structure into axisymmetric model, establish simplified model in the finite element software ANSYS, mainly through, mesh the region with the regular geometry by reflection method and the region the with the irregular geometry by free meshing method, press uniform load. The analysis results show that the tip of the crack exist singularity.
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LMI-Based on Robust Control of Uncertain Discrete-Time Systems With Multiple Time Delays
LI Yang
2012, 32 (4): 83-87. DOI:10.3696/j.issn.1672-6952.2012.04.022
Abstract ( ) PDF ( 935KB ) ( ) 　　
 
Focusing on a class of norm-bounded discrete-time uncertain systems with multiple delay, this paper presents new sufficient conditions to guarantee the robust stability of the system, and then proposed the relative guaranteed cost. By using Lyapunov method and linear matrix inequalities (LMI)，this article designs a state feedback robust controller for the closed loop system. An effective program for the guaranteed cost is offered. In the end, a simulation case is provided to illustrate the correctness and the effectiveness of the proposed theoretical results.
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Talent Selection Model Based on Fuzzy AHP and Fuzzy TOPSIS
LI Jin-qiu, YU Jing-xian， MIAO Chen
2012, 32 (4): 88-91. DOI:10.3696/j.issn.1672-6952.2012.04.023
Abstract ( ) PDF ( 884KB ) ( ) 　　
 
Considering the fuzziness of indicator weight and indicator value, a talent selection scheme is created. We firstly build up judgment matrix and evaluation matrix based on linguistic variables. Secondly, the linguistic variables are translated to triangle fuzzy numbers and the fuzzy judgment matrix and fuzzy evaluation matrix are got. Thirdly, we get the fuzzy weights of indicators by fuzzy AHP, and get the closeness coefficient and ranking of each evaluated object by fuzzy TOPSIS. At last taking the selection of team member of MCM for example, we illustrate the feasibility and efficiency of the scheme.
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Magnetostriction Coefficient of Amorphous Fe₇₈Si₉B₁₃ Under Two Distinctive Treatment
GUO Hong, CHEN Ming-ming
2012, 32 (4): 92-94. DOI:10.3696/j.issn.1672-6952.2012.04.024
Abstract ( ) PDF ( 904KB ) ( ) 　　
 
Amorphous alloy sample Fe₇₈Si₉B₁₃ is disposed by low frequency pulsating magnetic field and isothermic annealing, measuring magnetostriction coefficient by self-made magnetostriction coefficient measuring system. Results showed that both treatment process decreased the saturation magnetostriction coefficient λ_s of sample, λ_s is related with annealing time t and it reached minimal value 4.952×10^-5 when annealing under 300℃ for 40min. Saturation magnetostriction coefficient λs and low-frequency pulsed magnetic field strength Hp is nonlinear relationship, λ_s has a choice on the disposing parameters of pulsed magnetic field, λs reach minimal value 2.70×10^-5 when Hp equals to 19 900 A/m, pulsing frequency equals to 30Hz and processing time t equals to 240s. The impact of saturation magnetostriction coefficient by low frequency pulsed magnetic field is significantly greater than annealing.
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Probabilistic Computation Method for Some Types of Integral
YU Jing-xian, LI Jin-qiu, MIAO Chen
2012, 32 (4): 95-98. DOI:10.3696/j.issn.1672-6952.2012.04.025
Abstract ( ) PDF ( 936KB ) ( ) 　　
 
Considering the complexity and infeasibility of Newton-Leibniz formula in computing some types of integral, it was used the density functions and numerical characteristics of exponential distribution, normal distribution and chi-square distribution to compute three types of integral in calculus. Three computational formulas were got. Through the process of proof, it was found that the convenience of probabilistic method and close relationship between probability theory and calculus.
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