Electrochemical Characterisation of Passive Films Formed on X80 and X70 Pipeline Steels in NaHCO₃
LIANG Ping, LI Xiao-gang, DU Cui-wei, CHEN Xu, LIU Zhi-yong
2008, 21 (2): 1-5.
Abstract ( ) PDF ( 2325KB ) ( ) 　　
The passive behavior and electrochemical characterization of the passive films formed on X80 and X70 pipeline steels in 0.5 mol/L NaHCO₃ solution were discussed by potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and capacitance measurements. It is show that X80 and X70 pipeline steels present a wide passive anodic region (-0.16~0.90 V), the passive current density (ip) of X80 and X70 steels are 6.76 μA/cm² and 18.38 μA/cm², respectively. EIS results indicate that the surface of the passive film formed on X80 steel is much denser and uniformer than that of X70, and the result is also show by AFM. Mott-Schottky analyses displayed that the passive films on X80 and X70 pipeline steels in 0.5 mol/L NaHCO₃ exhibit n-type semiconductive characters in the potential region of -0.20 V to 0.80 V. Compared with the passive film of X70 steel, the donor density is much lower and the width of space charge layer is thicker for the passive film of X80 steel, so the corrosion resistance of the latter is better.
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The Synthesis of Poly(3-hexylthiophene) and Poly(3-dodecylthiophene)
WANG Shuang, ZHOU Hai, TONG La-ga, LU Yi-min, YANG Ying-ge, XIA Jin, ZHANG Lei
2008, 21 (2): 6-9.
Abstract ( ) PDF ( 2387KB ) ( ) 　　
P3HT and P3DDT were synthesized by the method of FeCl₃. Chemical structures were characterized by gel permeation chromatography(GPC) and 1H-NMR, thermal stability was studied by Tg. The absorption, fluorescence properties and the band gap of them in chloroform solutions and their spin-coating films were studied. The maximum Uv-vis wavelength of P3HT and P3DDT in chloroform solutions were 420 nm and 413 nm, respectively, and their corresponding emitted wavelengths are 602 nm and 573 nm.The maximum Uv-vis wavelength of their spin-coating films are 430 nm and 415 nm respectively, and their corresponding emitted wavelengths are 622 nm and 589 nm. Band gap data are 1.9 eV and 2.2 eV, respectively.
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Effect of Nucleating Agents on the Crystallization of Poly(lactide) 
SHEN Zhao-hong, QIAN Xin, QIAN Shi-jie
2008, 21 (2): 10-14.
Abstract ( ) PDF ( 5795KB ) ( ) 　　
Differential scanning calorimetry and polarizing optical microscope were used to characterize the melting behavior and isothermal crystallization kinetics of pure poly(lactide) and blends of PLA with nucleating agents at varying isothermal crystallization temperatures. Two small crystallization exothermic peak were observed prior to the major melting endothermic peak in the heating scans. This phenomenon occurred lower 10 ℃ in PLA/Talc blends. All nucleating agents increased the crystallization rate of PLA, but Talc was the most effective one. With Talc, at 125 ℃, t _1/2 from 7.78 min to 3.33 min, tmax from 7.84 min to 3.18 min; at 130 ℃,10 min,degree of crystallinity improved 19%.The nucleation mechanism and geometry of crystal growth of PLA and its blends are same. 
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Investigation on Isothermal Crystallization Kinetics of the MC Nylon 6/ZnO Nanocomposite
 
ZHOU Li, ZANG Shu-liang, TIAN Yan-wen
2008, 21 (2): 15-19.
Abstract ( ) PDF ( 2804KB ) ( ) 　　
The MC nylon 6/ZnO nanocomposite was prepared by using the in-situ polymerizing reaction, and its isothermal crystallization behavior was studied by the differential scanning calorimetry(DSC). The results show that the crystallization rate of both MC
nylon 6 and MC nylon 6/ZnO nanocomposite are controlled by the nucleating process at 188 ℃ to 196 ℃. As compared to MC nylon 6, the crystallization rate G of MC nylon 6/ZnO nanocomposite increases 0.1~0.3 min-1. It is found that the increase of the crystallization rate of MC nylon 6 due to the nano-sized ZnO was used as the heterophase crystal nucleating agents. For both MC nylon 6 and MC nylon 6/ZnO nanocomposite, with increasing the crystallization temperature, the crystallization rate G and its constant k is decreased, the time t1/2 of the half crystallization and that tmax of the maximum crystallization rate is shortened. However, for comparison with MC nylon 6, the decrease content is more obvious for MC nylon 6/ZnO nanocomposite.
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Preparation of Au/Co₃O₄ and  It’s Catalytic Performance for CO Oxidation   
 
HAI-Feng1,2, JIA Mei-lin, BAO Zhaorigetu, Mengntuya, LI Da， LI Yan-feng
2008, 21 (2): 20-24.
Abstract ( ) PDF ( 3598KB ) ( ) 　　
The different method and condition were used to prepare Au/Co₃O₄ catalysts and Co₃O₄ support.The aqueous precipitation and deposition-precipitation method were used to prepare Au/Co₃O₄ catalysts. The effect of preparation method and the condition of support on the catalyst activity of CO was investigated. The BET, XRD, TPR and XPS were carried out to analyze the influence factor on the catalysts activity. The results show that the catalytic activity is effected by preparation method distinctly, the catalyst prepared by deposition-precipitation method has higher activity than the other catalysts. Furthermore, the preparation conditions of support also affected the catalyst activity and the addition of dispersant and use of microwave in the support preparation process can improve the catalytic activity. The result of XPS indicates that Au δ+ species is catalytic activity component, the increasing of OH^- content can promote catalytic activity. The result of TPR indicates that addition of gold can accelerate the reduction of support and improve catalytic activity.
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The Application of BrØnsted Acidic Ionic Liquids in Alkylation Desulfurization of Gasoline
KE Ming, ZHOU Ai-guo, CAO Wen-zhi, SONG Zhao-zheng, JIANG Qing-zhe
2008, 21 (2): 25-28.
Abstract ( ) PDF ( 1135KB ) ( ) 　　
The application of BrØnsted acidic ionic liquids of ［BMIM］HSO₄ and H₂SO₄ as catalyst in alkylating desulfurization technology of gasoline was studied. The result shows that the mixture of ［BMIM］ HSO₄ and H₂SO₄ has better selectivity than sulfuric acid on catalyzing the alkylation of thiophene and alkene, under the same reaction condition. The conversion rate of thiophene increases as reaction temperature increases, but when the temperature is higher than 45 ℃, hexene decreases sharply due to polymerization. The conversion rate of thiophene increases with the increasing of reaction time, it costs about 2h to meet the equilibrium of reaction between thiophene and hexane.
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The QSPR Research of Photolysis Half-Lives of PCDD/Fs Adsorbed on Spruce Needles Foliage
DU Xi-hua, FENG Chang-jun
2008, 21 (2): 29-32.
Abstract ( ) PDF ( 1110KB ) ( ) 　　
The quantitative relationships between photolysis half-lives（t_1/2） and molecular structures of dioxins (PCDD/Fs) was described. Atomic characteristic value δi  of PCDD/Fs were defined. The topological descriptor Km and orientating group bedeck index mXJ were acquired by the technique of molecule graphics and AM1. The QSPR model，which could predict photolysis half-lives of PCDD/Fs adsorbed to spruce needle surfaces，were established using the index，the regression equations was proposed with mean deviation was 0.056. A modified leave-one-out procedure test was performed to validate model robustness，predicted the t_1/2 of other some PCDD/Fs molecules by the regression equation，and the error analysis were discussed. The results show that the model developed can make a better agreement between predicted and observed values of t_1/2.
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The Synthesis, Characterization and Catalytic Performance Research of the Si-Al Composite Zeolite
LI Feng-yan, ZHANG Ling-ling, SUN Gui-da, ZHAO Tian-bo
2008, 21 (2): 33-35.
Abstract ( ) PDF ( 1723KB ) ( ) 　　
A kind of Si-Al composite zeolite was synthesized by hydrothermal method and characterized by XRD, nitrogen adsorption-desorption and IR. The results of XRD show that the zeolite belongs to hexagonal symmetry, and it is a pure phase. The composited zeolite possesses both microporous and mesoporous structures base on the pore size distributions, and presents much more Bronsted and Lewis acidic sites than HZSM-5. The catalytic cracking activity of 1,3,5-triisopropylbenzene over the hierarchical zeolite is more than that over HZSM-5 due to its mesopore structure and more acid amount.
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The Rhizosphere Effect in Phytoremediation of the Petroleum Polluted Soil
WANG Jing， ZHANG Zhong-zhi， SU You-ming， WEI Xiao-fang， HE Feng， HE Wei
2008, 21 (2): 36-40.
Abstract ( ) PDF ( 3209KB ) ( ) 　　
The experiment studied on the rhizosphere effect in phytoremediation of the petroleum polluted soil by three kinds of grasses which were Pannicum， Eleusine indica(L.) Gaerth and Tall Fescue. After a period of 150 d ,this pot experiment show that the three kinds of plants rhizosphere accelerated the degradation of petroleum in different degrees.The results show that the plant roots improved the soil moisture which increased 5% compared with unplanted control soil .The dehydrogenas activity is 0.61～1.20 times higher.The number of microorganisms in the rhizosphere increased three orders of magnitude.The abduction of plant rhizosphere environment and the coercion of petroleum changed the distribution and activity of microorganisms.The petroleum degradation rates in the rhizosphere are 22.1%～30.3% higher than in the unplanted control soil.The effect of rhizosphere degeneration changed the component of petroleum obviously.It strengthened the degeneration degree of normal hydrocarbons that had low and moderate carbon.The plant rhizosphere environment is favorable to degenerate the high-carbon hydrocarbons into the low-carbon hydrocarbons.At the same time the peak area ratios of Pr/nC₁₇,Ph/nC^₁₈ and Pr/Ph have been enhanced 0.99,2.69 and 1.25 respectively.It accelerated the isomerization of normal hydrocarbons.
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Selenium-Catalyzed Reduction of m-Dinitrobenzene to m-Nitroaniline With Hydrazine Hydrate
 
CAI Ke-ying， ZHOU Xiao， MA Yu-miao， ZONG Zhi-min， WEI Xian-yong
2008, 21 (2): 41-44.
Abstract ( ) PDF ( 988KB ) ( ) 　　
The reduction of m-Dinitrobenzene (m-DNB) to m-nitroaniline (m-NA) with selenium and hydrazine hydrate was studied under mild conditions. The effects of ratio of solvents, hydrazine hydrate amount, selenium amount and NaOH amount on the reduction of m-DNB to m-NA were investigated. The results show that selenium has high catalytic activity and selectivity for the reduction under mild conditions. Under the optimized conditions of V(ethanol)/V(water) = 10∶1, 2 mmol of m-DNB, 3.1 mmol of hydrazine hydrate, 0.04 g of NaOH, 0.02 g of selenium, 75 ℃ and 2 h, the m-DNB conversion and the m-NA selectivity can reach 100 % and 98.7 %, respectively.
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Research on the Modified PC/ABS Alloy Materials and Mechanical Performance
SI Chun-lei, BAO Jian-hua, WU Quan-cai
2008, 21 (2): 45-47.
Abstract ( ) PDF ( 1973KB ) ( ) 　　
PC/ABS alloy was prepared through melt blending process by using PC,ABS and different kinds of compatibilizing agents. The structure and mechanical properties were characterized by DSC and normal mechanical measurement methods. The results show that PC/ABS belongs to partially-compatible system, the compatibility and mechanical properties could be improved when compatibilizing agents ABS-g-MAH and PE-g-MAH were added to the blending system. The modification effect of ABS-g-MAH is better than that of PE-g-MAH. The reason is that the similar molecular structure of ABS-g-MAH and PC/ABS alloy, at the same time, the interface adhesion could be improved through ester exchange reaction between acid anhydride in ABS-g-MAH and PC.
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Interactions Between LAS and Aniline Adsorptions on Riverbed Sediments
WU Yao-guo, HU Si-hai，　LIU Bao-chao, TAN Ying
2008, 21 (2): 48-52.
Abstract ( ) PDF ( 2073KB ) ( ) 　　
Batch equilibration experiment was conducted out to study the adsorptions of aniline and LAS and their interactions on Weihe riverbed sediments. The results show that, LAS inhibits to the absorption of aniline on the sediments, and so as to the inhibition of aniline on LAS adsorption on the sediments, because they compete with each other for adsorption sites on the sediments. The inhibitions are gotten increasing with rising in their concentrations, the adsorption models of LAS and aniline on the sediments are hardly affected by each other, however, varied with the changes in pH. The adsorption model of aniline obeys Henry equation under pH 5, and follows Freundlich or Langmuir equation under pH 7 or 9 respectively. The affect of aniline on the adsorption of LAS depends mainly on LAS concentration, and gets more distinct with increasing in the concentration. 
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The Synthesis of 1-Chloro-2,4,5-Trimethyl-Benzene
LIU Lin， XING Jin-juan， QIAN Jian-huan， ZHANG Qin-chun
2008, 21 (2): 53-54.
Abstract ( ) PDF ( 951KB ) ( ) 　　
1-Chloro-2,4,5-trimethyl-benzene was synthesized by one-step method, unsym- trimethylbenzene as the raw material, while HCl-H₂O₂-CH₃COOH as the catalytic activity system. By the orthorhombic experiment, the influenced factors are considered and the optimum conditions are confirmed. The experiment was carried under 60℃ for 2 h, while the mole ratio of H₂O₂ and unsym- trimethylbenzene is 4.5, HCl and unsym- trimethylbenzene is 4.0. The average yield was 82.8%, and the conversion rate was 98.4% while the fineness 99% under those conditions.
 
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Gas-Liquid Phase Equilibrium of Methyl Chloride-n-Hexane Binary System Calculated by SRK State Equation
SHANG Yu-wei, ZHANG Yan, GUO Wen-li， LI Shu-xin
2008, 21 (2): 55-58.
Abstract ( ) PDF ( 1448KB ) ( ) 　　
Gas-liquid phase equilibrium data of methyl chloride-n-hexane binary system was measured by phase equilibrium apparatus in which liquid circulates. Experimental data was regressed and Binary parameter of methyl chloride and n-hexane kij was calculated by SRK state equation，which is 0.05. It was found that liquid phase constitute of methyl chloride in n-hexane decreases with the increase of temperature，but increases with the increase of pressure.The average standard deviation of CH₃Cl gas constitute was 1.076 4% and the average standard deviation of pressure was 0.985 4%, which explain SRK state equation is accurate in regressing gas-liquid phase equilibrium data.Basing on it, gas-liquid phase equilibrium data of methyl chloride-n-hexane binary system in all concentration range were calculated. p-x,y phase graph at 25,30,40,50 ℃ was obtained.
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Numerical Simulation of Residence Time Distribution in Kenics Static Mixer
MENG Hui-bo, WU Jian-hua, YU Yan-fang
2008, 21 (2): 59-62.
Abstract ( ) PDF ( 2942KB ) ( ) 　　
The concentration response curves were calculated based on pulse tracer input technique by means of CFD method adopted RANS equations and renormalization group k-ε turbulence model. The characteristic of residence time distribution measured at different outlet with different inlet velocities and aspect ratios were ealeulated and analyzed by orthogonal experiment, and the orders of factors were ranked by the range analysis of mean value and square deviation. The results show that the order of axial back mixing coefficient is 10^-2, and the flowing state of the fluid in the kenics static mixer approaches plug flows. The mean residence time decreases with increasing flow rate of the fluid and increases with the increasing length and aspect ratio of the static mixers.
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The Numerical Simulation for Micropolar Fluids Field of Mixing Friction in Mechanical Seal
DING Xue-xing, CHENG Xiang-ping，LI Guo-dong, WANG Xun-jie，ZHANG Wei-zheng
2008, 21 (2): 63-67.
Abstract ( ) PDF ( 5428KB ) ( ) 　　
It is quite difficult to solve the problem of mixing friction in mechanical seal has relation to coupling function on more physical quantities between spring deformation and elastic hydrodynamic lubrication. And no available business software can directly work it out, so the C language programming was used to calculate. Allowing for micropolar fluids effect, dynamics and mathematical models on mixing friction in mechanical seal were established, and the problems for the distributions of fluid film pressure in film lubrication under the different micropolar fluids parameters were solved by using finite difference method, then the solutions of pressure and spillage value were obtained. The results show that raising of micropolar fluids parameters such as coupling coefficient and characteristic length makes fluid film pressure increase, and then pressure drops and spillage decreases, which keeps seal reliability.
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Calculate the Temperature of Oxygen Ethanol Flame and Analysis on Cutting Test
YAN Li-jun， HU Chuan-shun， JIANG Ying-tian， CHEN Qiang， LI Xian-chen
2008, 21 (2): 68-70.
Abstract ( ) PDF ( 1003KB ) ( ) 　　
Combustion performance of oxygen ethanol and thermal change in combustion reaction process was analyzed. Calculate the theoretical temperature of oxygen ethanol flame by thermodynamic theory. Relationship between the combustion temperature and the reactant was  confirmed,so oxygen ethanol flame can be used in metal oxygen cutting. Feasibility of this method was proofed in further by cutting test and compare with oxygen acetylene. The results show that using appropriate technology in cutting conditions, the quality of slot may meet needs.
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Measurement of Density-Pressure-Temperature Relation for Foam Fluid
LI Song-yan, LIN Ri-yi, LI Zhao-min, SHANG Zhao-hui, CAO Li-zhao
2008, 21 (2): 71-75.
Abstract ( ) PDF ( 4850KB ) ( ) 　　
Foam fluid has good property, widely used in petroleum engineering. Density of foam fluid is very important in site application. Device designing used to measure density of foam fluid was introduced under underhole situation. Method to quantitatively determine the density-pressure-temperature relation of the foam fluid was also put forward. The relations between the density of the foam fluid and the pressure and temperature were measured using the method. Experiential formulas calculating density of foam fluid were gained through regression method. The results of measurement and conventional calculation were compared. It shows that density of foam fluid increases with pressure increases, and decreases with temperature increases. The larger the ratio of gas and liquid weight in foam fluid is, the better the condensability of foam fluid is. The measured density of foam fluid is always less than that of calculated by conventional method. Difference lies in 1.45 %to 11.31%. The reason is that repellent force of surfactant ions has not been considered when calculating by conventional method. The regressed formulas have good accordance with the experimental data. The research conclusions can direct foam fluid application in oil field.
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Improvement and Application of the Algorithm of Making Stripping Schedule for Certain Multi-Product Pipeline
ZHANG Qiang, LIANG Yong-tu, WANG Da-peng, LIU Zeng-zhe, GONG Jing*
2008, 21 (2): 76-79.
Abstract ( ) PDF ( 2331KB ) ( ) 　　
Algorithm of making stripping schedule for multi-product pipeline available had their own defects and limitations. It could not be applied to multi-product pipeline in China directly. The new algorithm for certain multi-product pipeline was put forwards to make stripping schedule on the basis of referring to master-clock method and adopting its advantages of speeding the calculation through variable paces and being flexible and adding interface′s reaching stations to the set of control points and introducing capacity of the pipeline as a constraint, in which almost all factors considered when manually making a new schedule are involved. The algorithm can track positions of interfaces all time. The corresponding software has been developed which is being applied on three pipelines in China. The application shows that the algorithm is feasible.
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Analysis on Flow and Heat Transfer of Fluid in  Porous Metal Foam Heat Exchanger
LI Ju-xiang1， TU Shan-dong2
2008, 21 (2): 80-83.
Abstract ( ) PDF ( 2955KB ) ( ) 　　
The flow and heat transfer under the constant heat flux condition of fluid′s outside the tube forced laminar flow along the tube axis in a quadrate tube-shell type heat exchanger fitted with porous metal foam in shell side was theoretically analyzed. It shows that the flow velocity distribution in the radial direction is similar to the situation of fluid′s internal turbulent flow inside a blank tube with the feature of having great gradient in a very thin layer near to the wall and more flat in the rest area. The temperature distributions of fluid and foam are more flat. The increasing of the pressure drop of the fluid with the ppi（pore per inch）number of the porous metal foam was faster than that of the Nusselt number of the convection heat transfer. The pressure drop and the Nusselt number were increased with the decreasing of the porosity of the porous metal foam.
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Based on  N  Shortest Path Optimal Design the Products Pipeline
CHU Fei-xue, WU Xian-ce, ZHANG Zong-wei
2008, 21 (2): 84-88.
Abstract ( ) PDF ( 1487KB ) ( ) 　　
Under condition of the possible locations of the pump station were determined. And   applied directed edge-weight graph to describe the optimization problem of the products pipeline, and graph theory was used to analyze the problem. The candidate pump station locations were taken as the vertices and the total cost of the pipeline system between the two vertices were looked as the edge-weighted. Then algorithm recursively calling the Dijkstra algorithm was designed and analyzed to obtain N shortest paths, so the optimal alternative and the quasi-optimal alternatives were obtained at the same time, these alternatives can be used to compare by the designer. Moreover, the algorithm was tested by a real example; it can meet the need of real application. Applied this method can avoid adjustment the locations of the pump station, and more fit the need of the engineering. It also can be extended to the other long-distance oil or gas pipeline optimal design.
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Stability of a Class of Uncertain Fuzzy Systemsbased on Controller Switching
LIANG Xiao-min, NIE Hong
2008, 21 (2): 89-92.
Abstract ( ) PDF ( 2538KB ) ( ) 　　
 
The problem of stability for a class of T-S fuzzy time-delay systems was investigated . By using controller switching technique and multiple Lyapunov function method, in several proposed PDC controllers, an appropriate switching law was designed to ensure that the closed-loop system is asymptotically stable for all admissible uncertainties. A simulation result demonstrates the feasibility and the effectiveness of the designed method.
 
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Novel Online Iterative Reconstruction Technique  for Electrical Capacitance Tomography
DONG Xiang-yuan, GUO Shu-qing, LIU Shi
2008, 21 (2): 93-96.
Abstract ( ) PDF ( 2538KB ) ( ) 　　
 
Fast algorithm with high spatial resolution was the key to electrical capacitance tomography(ECT). A fast iterative scheme for electrical capacitance tomography was presented based on the Landweber iteration method. The convergence condition for the new method was also discussed. Simulated data were analyzed to evaluate the performance of the method. The results indicate that it can produce similar quality images with less reconstruction time when compared to the Landweber iteration algorithm. The reconstruction time does not depend heavily on the number of pixels. It shows good potential for online image reconstruction.
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