The Preparation and Characterization of Electrochemical Capability of RuO₂/Polyaniline Composite
CHEN Gao-feng,XU Jie,ZHOU Xun,DU Nan-xuan,
2009, 22 (4): 1-4. DOI:10.3696/j.issn.1006-396X.2009.04.001
Abstract ( ) PDF ( 337KB ) ( ) 　　
Nanometer RuO₂ particle were prepared by sol-hydrothermally method using RuCl₃·nH₂O as raw material,and RuO₂ /polyaniline composite were fabricated from aniline polymerization in RuO₂ sol by conventional chemical oxidation.The morphology and microstructure were characterized by SEM and XRD,and its electrochemical properties were investigated with cyclic voltammetry.The results indicate that the structure of the composites vary by different mass fraction of RuO₂.When the mass fraction of RuO₂ is 5%,compact RuO₂ coats are formed on the surface of polyaniline particles,and electrochemical capacitance of the composite diminish due to polyaniline capacitance disappearance.RuO₂ particles are dispersed in the polyaniline when the mass fraction of RuO₂ is more or less than 5%.The capacitance of the composite reaches the maximum is 374.6 F/g when the RuO₂ mass fraction is 3%.The composite with less RuO₂ content has good electrochemical property which is suitable for supercapacitors.
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Synthesis of Al/La-Cross-Linked Montmorillonite and Catalytic Property
SONG Xu-dong, JIA Li-hua, GUO Xiang-feng, Zhang Sen
2009, 22 (4): 5-8. DOI:10.3696/j.issn.1006-396X.2009.04.002
Abstract ( ) PDF ( 313KB ) ( ) 　　
Al/La-pillared and Al-pillared montmorillonite were prepared from the raw material Na-montmorillonite, and characterized by XRD, nitrogen adsorption, NH₃-TPD, SEM and particle distribution. The ketalation was used as a probe reaction to study the catalyst activity of Al/La-pillared montmorillonite, and compared with Al-pillared montmorillonite. The results show that the crystal form of Al/La-pillared montmorillonite is more better than Al-pillared montmorillonite, the interlamellar spacing is more bigger than Na-montmorillonite. When n(Al)/n(La) is 25∶1 and n(Al+La)/n(Na-mont） is 2, the interlamellar spacing of Al/La-pillared montmorillonite is 1.81 nm, the surface area of BET is 183 m2/g, and the temperature of NH3-desorption(228 ℃) than Al-pillared montmorillonite is 70 ℃. The yield of cyclohexanone ethylene ketal can reach 85% in the presence of Al/La -pillared montmorillonite. 
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Synthesis and Characterization of Ni/Al Composite Oxide Mesoporous Materia
SONG Wei-ming, LIU Fang,DENG Qi-gang
2009, 22 (4): 9-12. DOI:10.3696/j.issn.1006-396X.2009.04.003
Abstract ( ) PDF ( 294KB ) ( ) 　　
Mesoporous Ni/Al composite oxides were synthesized by hydrothermal ultrasonic reaction using anionic surfactant as templating agent, Al(NO₃)₃·9H₂O as aluminium source and NiCl₂·6H₂O as nickel source. The samples appear  mesoporous phases when the n(Ni)/n(Al)=1∶7, reaction temperature 80 ℃, reaction time 28 h, crystallization of 12 h. The samples were characterized by XRD, FT-IR, N₂  adsorption-desorption, NH₃-TPD, CO₂-TPD, TPR,TPO and so on. The experimental results indicate that samples exhibit typical mesoporous structural characteristics with a narrow distribution of pore size, average pore size is 2.6 nm, pore volume is 0.216 cm³/g, surface areas is 297.132 m²/g. The samples exhibit weak and strong acid-base center,at same time, could been oxidized at 340 ℃ and reduced at 430 ℃.
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The Synthesis and Its Solution Properties of Gemini Sodium Nonylphenol Polyoxyethylene Ether Sulfate
ZHANG Bin,LI Gang,YANG Fang,et al
2009, 22 (4): 13-17. DOI:10.3696/j.issn.1006-396X.2009.04.004
Abstract ( ) PDF ( 314KB ) ( ) 　　
The gemini sodium nonylphenol polyoxyethylene ether sulfate （GNPES ） was synthesized from nonylphenol， paraformaldehyde，ethylene oxide，sulfamic acid and aqueous sodium hydroxide by a three－step．Critical micelle concentration （CMC），micelle aggregation numbers at different surfactant concentrations and micellar micropolarity of GNPES and sodium nonylphenol polyoxyethylene ether sulfate （NPES） were individually determined by steady－state fluorescence probe method inwhich pyrene was used as fluorescence probe and benzophenone was used as quencher． The influence of the change of hydrophilic polyoxyethylene group of GNPES and NPES on the aggregation properties was studied respectively．The varieties of N with the concentration of GNPES and NPES were also discussed．The experimental results show that the CMC of GNPES reduce about one quantitative than the CMC of NPES，but the effect of redusing surface tension of GNPES and NPES is closely． When hydrophilic group is longer， Nm of GNPES surfactants and NPES surfactants increase，and the Nm's increasing trend of NPES is stronger than those of GNPES ．
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Preparation and Characterization of SBA-15 Molecular Sieve Modied by Zn-SO₄^2- and Catalytic Activity in Esterification of Methyllaurate
TIAN Zhi-ming, LIU Mei-hua, DENG Qi-gang,et al
2009, 22 (4): 18-21. DOI:10.3696/j.issn.1006-396X.2009.04.005
Abstract ( ) PDF ( 315KB ) ( ) 　　
 Zn－SO^2-₄／SBA－15 composite material was prepared by manually grinding.ZnO and (NH₄)₂SO₄ were highly dispersed in SBA-15.  Zn－SO^2-₄／SBA－15was characterized by means of XRD, nitrogen adsorption, IR and TG.The esults show that the prepared catalyst keep highly ordered mesoporous one-dimensional hexagonal structure．Acid strength on catalyst surface is in range of 2.8~3.3，acid content of 2.42 mmol/g, determined by means of Hammett indication method.Methyllaurate was synthesized from lauric acid and methanol over  Zn－SO^2-₄／SBA－15 as catalyst.The optimum conditions were determined by orthogonal experiment：molar ratio of lauric acid to methanol 1∶15，mass of the catalyst is 1.0 g， reaction time 10 h.The yield of methyllaurate can reach 85.4 %.The results show that the solid acid have higher catalytic activity.
 
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The Production of Side Chain Dodecylphenol by Triisobutene
SHANG Yu-wei,LI Shao-ran,GUO Wen-li,et al
2009, 22 (4): 22-25. DOI:10.3696/j.issn.1006-396X.2009.04.006
Abstract ( ) PDF ( 265KB ) ( ) 　　
Using cation exchange resins Amberlyst 15 as catalyst, triisobutene and phenol as raw materials, synthesized branched-chain dodecylphenol. The effects of temperature, time, the amount of catalyst and mole ratio of phenol and olefin on the alkylation were researched. The impacts conditions were optimized by orthogonal experiment.The results show that alkylation of time is 8 h; mole ratio of phenol and olefin is 6; mass fraction of catalyst is 20% ; reaction temperature is 45 ℃, the maximum dodecylphenol yield (47.1%) could be obtained so that the utilization of triisobutene could reach 90.2%, the yield of branched-chain dodecylphenol could up to 50%.
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Preparation of Mo-V-Te-Nb-O Catalyst for the Selective Oxidation of Propane to Acrylic Acid
ZHU Bao-dong, WANG Jian, DONG Qun, GUO Li
2009, 22 (4): 26-28. DOI:10.3696/j.issn.1006-396X.2009.04.007
Abstract ( ) PDF ( 268KB ) ( ) 　　
Mo-V-Te-Nb-O catalysts were prepared by aqueous solution. Effects of dryness and calcinations modes in catalyst preparation on the catalyst structure and performance were studied by XRD, BET and continuous fixed-bed microreactor. Compared to the catalyst prepared by dry under ordinary pressure method, the catalyst by rotary evaporation under the decompression was more favorable. The catalyst precursor for even distribution in the active component can be generated easier. The proportion of M1 and M2 phase in the catalyst structure which were conducive to improve the activity and selectivity in catalyst were larger. The catalyst surface area was also increased by 31.5%. The suitable rotating evaporating temperature was 50 ℃; the effects of N₂ and He in calcinations to the structure and properties of catalysts were the same to prevent air oxidation. The Te content in the catalyst which was pre-calcination 60 min in air at 275 ℃ was increased，and the catalyst surface area was 2.78 m²/g. The C_3H8 conversion was 47.6% and the acrylic acid selectivity was 50.5% when the reaction temperature was 360 ℃.
 
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Estimation of Thermodynamic Properties of PBTAs Using the Molecular Electronegativity Distance Vector
CHEN Yan， DU Xi-hua
2009, 22 (4): 29-33. DOI:10.3696/j.issn.1006-396X.2009.04.008
Abstract ( ) PDF ( 295KB ) ( ) 　　
Based on the molecular electronegativity distance vector, the quantitative structure-property relationship (QSPR) models of the thermodynamic properties (standard enthalpy H⁰，free energy G⁰，heat capacity at constant volume C⁰_V and standard entropy S⁰) were constructed for TA and 75 PBTAs. From the four parameters of the model, it was known that the molecular structure fragents: [CDS1]CH—,[CDS1]Ｃ＜,－S－,－Br were all the dominant influencing factors of thermodynamic properties. The optimal bivariate correlation (R²) of these QSPR models were all 1.000, and the calculated values were in good agreement with experimental data and favorable with literature data. The results show that the possess better predictability and robustness by Jackknifed method and cross-validation procedure. It can be expected that the molecular electronegativity distance vector will be used widely in quantitative structure-property/activity relationship research.
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Application of Green Fluorescent Protein as Gene Marker for Microbial Enhanced Oil Recovery
ZHANG Zhong-zhi, SUN Shan-shan, WANG Yu-xiao，et al
2009, 22 (4): 34-37. DOI:10.3696/j.issn.1006-396X.2009.04.009
Abstract ( ) PDF ( 345KB ) ( ) 　　
In order to obtain more analyses and estimate correctly and accurately to improve Microbial Enhanced Oil Recovery (MEOR), goal strains for MEOR would be marked and tracked to indicate that how and where they moved and reproduced in oil reservoir and show their amount and rate in oil-field microorganism. Recombinant plasmid of pET-30a(+)-EGFP which has the gene of green fluorescent protein (GFP) was constructed and transferred into JD successfully . Recombinant plasmid can be stably maintained in the culture media including 50 μg/mL kanamycin (Kan), which indicated recombinant plasmid stability under choice pressure, while without kanamycin it can be lost easily. JD(gfp) can normally reproduce and metabolize together with wild strain for MEOR isolated from oil reservoir while no transfer of recombinant plasmid.
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Determination of Diffusion Coefficient for Carbon Dioxide in the Porous Media
GUO Biao, HOU Ji-rui, YU Chun-lei,et al
2009, 22 (4): 38-40. DOI:10.3696/j.issn.1006-396X.2009.04.010
Abstract ( ) PDF ( 199KB ) ( ) 　　
The diffusion coefficient of carbon dioxide in the formation for explored oil by carbon dioxide injected was researched. The one-dimension diffusion equation, combined the second Fikes law and continuity equation was deduced. There were some merits: the porous media was stuffed with outcropping sand; the device was placed horizontally, which eliminated the convective diffusion; the simulator is 1 m, which could erase the boundary effect. The  derive the diffusion coefficient for diverse pressures under the temperature at 60 ℃. The physical simulator was packed the outcropping sand, which was much more agreeable with the reality. The results can be used for parameter optimization in the field for CO₂ flooding. 
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Application of Thermophiles in Microbial Enhanced Oil Recovery
SUN Shan-shan, ZHANG Zhong-zhi,LU Mang, et al
2009, 22 (4): 41-44. DOI:10.3696/j.issn.1006-396X.2009.04.011
Abstract ( ) PDF ( 488KB ) ( ) 　　
The application of three thermophilic bacteria (named GW1, GW2, GW5, respectively) in microbial enhanced oil recovery (MEOR) was studied. The results show that the optimal temperature of three bacterium is 55 to 65 ℃, the optimum pH value is between 7 and 8, and the optimal salinity is 5 000-20 000 mg/L. GW1 is sensitive to sulphonate cleanup additive and frothing agent, frothing agent for GW2 is disincentive, and GW5 is susceptible to sulphonate cleanup additive. Thermophilic bacterium degraded the heavy components to light ones and increased the mobility of crude oil. GW1, GW2 and GW5 are identified as [WTBX]Geobacillus.
 
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The Determination of Intrinsic Viscosity of Super-High Relative Molecular Weight Polyacrylamide
TAO Lei,ZHANG Na,DU Can-min,et al
2009, 22 (4): 45-48. DOI:10.3696/j.issn.1006-396X.2009.04.012
Abstract ( ) PDF ( 266KB ) ( ) 　　
For the super-high relative molecular weight polyacrylamide，the rheological behaviour and viscoelasticity were more complicated．The capillary tube method which was based on Newtonian fluid theory had much bigger error on measuring the intrinsic viscosity．The rheological behaviour of super－high relative molecular weight polyacrylamide of Shengli oilfield was analyzed．The viscosity－temperature curve，rheological curve and the viscosity at fixed share rate were measured．Then the experimental condition under low share rate and low concentration was established．The results show that the rheometer is closer to the real relative molecular weight and the linearity of ηs p ／C ～ C and lnηr ／C ～ C are better and mensuration is exact and credible．
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The Effects of Wettability on Oil Recovery Efficiency
SONG Xin-wang,CHENG Hao-ran,CAO Xu-long,et al
2009, 22 (4): 49-52. DOI:10.3696/j.issn.1006-396X.2009.04.013
Abstract ( ) PDF ( 264KB ) ( ) 　　
For achieving a better understanding of the effects of wettability on the oil recovery,the core displacement experiments were carried out.By using outcrop man-made cores with low,middle and high permeability,and convertingcores wettability from water-wet and oil-wet to intermediate wet,the oil recovery efficiency after water flooding on the cores was studied.The results show that converting cores wettability from water-wet and oil-wet to intermediate wet is favorable to decreasing maximumly the capillary force as a resistance force in reservoir pores,and enhancing water displacement effects.So the suggestion that the wettability of water-wet and oil-wet should be changed into intermediate wet on the experimental condition.
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Multidimensional CFD Researchon PolycyclicA romatic Hydrocarbons in Iso-Octane HCCI Combustion
ZENG Wen,SONG Chong-lin
2009, 22 (4): 53-57. DOI:10.3696/j.issn.1006-396X.2009.04.014
Abstract ( ) PDF ( 439KB ) ( ) 　　
By coupling the KIVA-3V engine CFD package with the CHEMKIN III chemical kinetics package, the formation and evolvement mechanisms of the aromatic (benzene) and polycyclic aromatic hydrocarbons (include naphthalene, phenanthrene and pyrene) in iso-octane HCCI combustion were simulated. Iso-octane was used as fuel and the detailed reaction mechanisms of combustion of iso-octane and formation of the polycyclic aromatic hydrocarbons were adopted. The results show that the numerical simulations of the pressure and heat release through this computational model are the same as the experimental results. Before ignition, the mass fraction fields of A₁(benzene), A₂(naphthalene), A₃(phenanthrene) and A₄(pyrene) are very inhomogeneous. Comparing with the boundary zone and the crevice zone, the mass fractions of A₁-A₄ in the core zone are higher. After ignition, comparing with the core zone and the crevice zone, the mass fractions of A₁-A₄ in the boundary zone are higher. At the time as the vent opening, comparing with the core zone and the boundary zone, the mass fractions of A₁-A₄ in the crevice zone are higher. At the same time, among these four aromatic and polycyclic aromatic hydrocarbons, the mass fraction of A₁ is the highest, A₂ is following, and A₄ is almost zero.
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The Definition and Determination of the Critical Fouling Layer Thickness
WU Shuang-ying, SU Chang, LI You-rong
2009, 22 (4): 58-62. DOI:10.3696/j.issn.1006-396X.2009.04.015
Abstract ( ) PDF ( 285KB ) ( ) 　　
Based on the effect of fouling on heat transfer process，the critical fouling layer thickness was firstly put forward． The expressions of the critical fouling layer thickness were given and the effect of relative parameters on the critical fouling
layer thickness was discussed．In the meantime， the critical fouling layer thickness was compared with the critical thermal insulation layer thickness．The results show that the critical fouling layer thickness may be theoretically used to explain the phenomena of enhancement heat transfer at the initial forming period of fouling under fixed conditions． Furthermore， the critical fouling layer thickness is determined by mass flow rate of fluid， the physical properties of fluid and the thermal conductivity of fouling layer itself， etc． Meanwhile， the presence of the critical fouling layer thickness is subjected to the specific conditions of convective heat transfer，and the critical fouling layer thickness is different from the critical thermal insulation layer thickness although the fouling layer and thermal insulation layer both have poor thermal conductivity．
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Research on the Risk Grading Division of Oil and Gas Pipeline Based on WebGIS
WANG Wei-qiang,WU Ming,WANG Yong,et al
2009, 22 (4): 63-66. DOI:10.3696/j.issn.1006-396X.2009.04.016
Abstract ( ) PDF ( 417KB ) ( ) 　　
The safety management was among the most important management work for oil and gas pipelines． As an alternative，the risk grading division based on WebGIS was being considered to improve safety management．An information
management system for oil and gas pipeline based on WebGIS had been established using ArcGIS Server as the developing system of WebGIS，SQL Server as the database to store pipeline data and ArcSDE as the GIS Server．According to the practical pipeline situations，the expert grading method on risk assessment of oil and gas pipeline set by Muhlbauer W K was modified．
An analytic hierarchy process （AHP） was introduced to comprehensively evaluate the expert grading method，and a kind of categorization method for the risk of oil and gas pipelines was proposed．Finally，it was demonstrated with examples that this improved categorization method based on WebGIS is more intuitive and easier to apply．
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Influence of Heat Treatment on Microstructure and Corrosion Resistant Performance of Inconel718 Nickel-Base Alloy
SONG Yi-si， GAO Wan-fu， HU Zhuo-chan
2009, 22 (4): 67-71. DOI:10.3696/j.issn.1006-396X.2009.04.017
Abstract ( ) PDF ( 497KB ) ( ) 　　
The relation between microstructure and corrosion resistant performance on Inconel718 nickel-base alloy which were solution treated at 940～1 000 ℃ as well as solution treated and then aged at 720 ℃ for 8 h,50 ℃/h cooling and 620 ℃ for 8 h,was researched.The result show that the rigidity of alloy declined with solution temperature increasing.After solution and aging,the rigidity of alloy raised firstly then declined with temperature increasing,and reached the maximum at 980 ℃,the rigidities were the double of solution.Polarization curve and Alternating Current impedance were tested in 5% Na2SO4 acidity liquor which was regulated to pH of 3 with H2SO4 liquor.The result indicate that the corrosion resistant performance of samples which is solution treated and aged is worse than solution treated only.The simulation test at the high temperature and pressure H2S/CO2 stress corrosion condition indicated that the H2S/CO2 stress corrosion resistant performance of samples which are solution treated as well as solution treated and aged are both good.
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CFDA ssessment of the Impact Caused by Hydrogen Sulfide Leakages From Petrochemical Installations on Nearby Residents
ZHANG Bo, CHEN Guo-ming
2009, 22 (4): 72-76. DOI:10.3696/j.issn.1006-396X.2009.04.018
Abstract ( ) PDF ( 322KB ) ( ) 　　
Hydrogen sulfide leakages from a sulfide recycle installation in a petrochemical plant in different wind speeds were simulated based on CFD technique． The results show that wind speeds and turbulences are the determining factors which influence the dispersion．In a relatively low wind speed condition the dispersion speed is slow but it is benificial for the hydrogen sulfide to spread near the ground surface and the threats near the ground are greater．In a relatively fast wind speed condition the dispersion speed is fast and it is benificial for the hydrogen sulfide to spread into the upper air and the threats near the ground are smaller．Lastly，a contrast was drawn between the immediately lethal concentration ranges and the sensitive areas which have a concentrated population at a range of 3 km of the plant．And the results show that a 2 km range near the plant has higher degree of risks and the impact of 2 ～ 3 km range is smaller．
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Numerical Simulation on Soil Temperature Field Around Underground Hot Oil Pipelines and Medium Temperature-Dropin the Process of Staring
YE Zhi-wei, WANG Rui-jin
2009, 22 (4): 77-80. DOI:10.3696/j.issn.1006-396X.2009.04.019
Abstract ( ) PDF ( 284KB ) ( ) 　　
For drawing up science and reasonable preheating process of buried pipeline,the change of soil temperature field around pipeline and oil temperature within pipeline were accurately forecasted.The soil temperature fields around the buried pipeline in the process of preheating and oil temperature within pipeline were numerically simulated through using finite elements method,found out how the soil temperature around pipeline distribute and oil temperature within pipeline change at different time.Analysis the calculation results show that the on-way temperature dropping of oil in pipeline is influented obviously by comprehensive factors,such as preheating medium,time of preheating mixed medium,soil temperature,climate condition etc.Determination of economy and safe process of preheating mixed medium can make commissioning to operate economically and securely. ReplaceFont('ChDivSummary',');ReplaceFont('EnDivSummary','For drawing up science and reasonable preheating process of buried pipeline,the change of soil temperature field around pipeline and oil temperature within pipeline were accurately forecasted.The soil temperature fields around the buried pipeline in the process of preheating and oil temperature within pipeline were numerically simulated through using finite elements method,found out how the soil temperature around pipeline distribute and oil temperature within pipeline change at different time.Analysis the calculation results show that the on-way temperature dropping of oil in pipeline is influented obviously by comprehensive factors,such as preheating medium,time of preheating mixed medium,soil temperature,climate condition etc.Determination of economy and safe process of preheating mixed medium can make commissioning to operate economically and securely.');if(document.getElementById('ChDivSummary') != null && document.getElementById('ChDivSummary').innerHTML!=""){CutSpan('ChDivSummary',500);DisplaySpanDiv('ChDivSummary');ClearSummaryOnLoad('SummaryLinkChID','SummaryLinkEnID');} if(document.getElementById('EnDivSummary') != null && document.getElementById('EnDivSummary').innerHTML!=""){CutSpan('EnDivSummary',1000);DisplaySpanDiv('EnDivSummary');ClearSummaryOnLoad('SummaryLinkEnID','SummaryLinkChID');}ReplaceChar1('ChDivSummary');ReplaceChar('ChDivSummary');ReplaceChar1('EnDivSummary');ReplaceChar('EnDivSummary');
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The Simplified Calculation of Axial Force of Submarine Pipe Under Earthquake Load
ZHU Yi, XIE Yu-jun
2009, 22 (4): 81-83. DOI:10.3696/j.issn.1006-396X.2009.04.020
Abstract ( ) PDF ( 175KB ) ( ) 　　
The earthquake wave broadcasting through the ground leads a ground dissemination when the earthquake happen， then the ground moves along the pipe axial displacement makes the axial tensile stress．Neglect inertial force，but considering dynamic water pressure．Adoption the statical analysis method to analysis ascending pipe stress，and incorporation a calculation
example using Ansys software to analyze submarine pipeline axial stress．The example was analysis and got the conclusion was that the submarine pipeline could not be broke where ９ degrees earthquake intensity happened.
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Adaptive Weighted Least Square Support Vector Machine Regression and Its Application
CUI Wen-tong,LIN Wen-cai,YAN Xue-feng
2009, 22 (4): 84-88. DOI:10.3696/j.issn.1006-396X.2009.04.021
Abstract ( ) PDF ( 308KB ) ( ) 　　
In order to eliminate the influence of unavoidable outliers in soft sensor sample data on model's performance,a novel adaptive weighted least square support vector machine regression method(AWLS-SVM) was proposed.Firstly,in AWLS-SVM,least square support vector machine regression was employed for the sample data to develop model and obtain the sample datum fitting error.Then,according to the fitting error,the initial error weight was calculated.Secondly,the lever weight was defined according to the space distribution of the sample data.Finally,combining the error weights and lever weights,the adaptive sample weights were obtained via the proposed adaptive iterative method.Thus,the model was developed by AWLS-SVM with the adaptive sample weights.The simulation experiment results show that the outliers influence on the model's performance is eliminated in AWLS-SVM,and that the prediction performance is better than those of LS-SVM and radial basis function network method.Further,AWLS-SVM was applied to develop the soft sensor model for 4-carboxybenzaldehyde concentration in terephthalic acid,which is the most important intermediate product of p-xylene oxidation to terephthalic acid reaction.The satisfied result is obtained.onclick="SelectDisplayDiv('EnDivSummaryMore','EnDivSummaryHuanYuan');HideSpanDiv('EnDivSummaryMoreSummary')">
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Process Modeling Based on SOM-PCA-RVM and Its Application
LI Xin, YAN Xue-feng
2009, 22 (4): 89-94. DOI:10.3696/j.issn.1006-396X.2009.04.022
Abstract ( ) PDF ( 302KB ) ( ) 　　
A hybrid modeling method for the complex process was proposed．The process，which was highly nonlinearity，had interacting independent variables， and had process data belonged to different categories． This method combined self－organizing map network （SOM network），principal component analysis （PCA），and relevance vector machine （RVM）．First，
divided the sample datum into several subspaces which had the same patterns with the utilizing of SOM，the pattern space separation was realized．Then derived the principal components based on the modeling samples of each subspace，defined the optimal principal component numbers based on prediction ability，and filtered the redundancy．At last，the principal component
of each subspace was applied as the input of RVM，building the models individually ，and the classifying modeling was realized based on the separated of sample pattern spaces．The simulation results and the application in 4－carboxybenzaldehyde content soft sensor of pureed terephthalic acid production show that the accuracies of regressing and predicting of SOM－PCA －RVM model is better than both RVM model and PCA － RVM model．
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A Slide Mode Control-Common Model Control Controller for BUCK Converter
CHANG Liang， FAN Si-liang， GUO Bing-jun
2009, 22 (4): 95-98. DOI:10.3696/j.issn.1006-396X.2009.04.023
Abstract ( ) PDF ( 291KB ) ( ) 　　
A slide mode control－common model control（SMC－CMC） controller was proposed to deal with the time－variable and complexity of the switching mode power converters．Using the state－space average modeling method，a nonlinear model of BUCK converter working on current conduction mode （CCM） was set up．Dynamic neural network which was constructed based
on a number of integrators and RBF neural network was employed to approximate the inverse model of the dynamic system． Using this inverse model to build a CMC controller．The introduction of slide mode control was to improve the robustness of controller．The modeling and simulation of system was implemented under Matlab／Simulink．The result of simulation confirms
show that the SMC－CMC control schemes are capable of reduced steady state error and improve controll‐er's reliability during supply change and load variations．
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