Industrial Trials of Linear Alkyl Benzene Using Two Paraffin Materials
BAI Gang, CHEN Jie-jing, WAN Hai, SONG Li-juan
2010, 30 (4): 1-03. DOI:10.3696/j.issn.1672-6952.2010.04.001
Abstract ( ) PDF ( 499KB ) ( ) 　　
Two paraffins as raw materials were selected to mix with MOLEX paraffin and used to make a industrial trial in UOP-HF process of linear alkyl benzene (LAB). Influence on LAB quality and process was tested. The result shows that the LAB product can meet national standard specification but process parameters changed by the method above at certain proportion. Further sulfonation industrial test shows that the alkyl benzene sulfonic acid can reach the requirements of national standard.
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Determination of Flavonoids From Codonopsis Pilosula With Spectrophotometer
WANG Qing-ming, ZHANG Jin-sheng, LI Li-hua, XUE Li-min
2010, 30 (4): 4-07. DOI:10.3696/j.issn.1672-6952.2010.04.002
Abstract ( ) PDF ( 195KB ) ( ) 　　
Flavonoids were extracted from codonopsis pilosula with microwave-assisted method, and its content was determined by spectrophotograpy. Two methods with NaNO2-Al(NO3)3 or AlCl3 as the chromogenic agent were performed and the precision, stability, reproducibility and recovery ratio of the two methods were studied. The results show that the AlCl3 colorimetric determination of flavonoids in codonopsis pilosula was simple, convenient, accurate and reliable as compared with the NaNO2-Al(NO3)3 colorimetric determination method.
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Relation Between Colloid Stability of Residuum and Coke Formation During Thermal Reaction
2010, 30 (4): 8-10. DOI:10.3696/j.issn.1672-6952.2010.04.003
Abstract ( ) PDF ( 202KB ) ( ) 　　
Colloidal stability of Liaohe vacuum residuum(LHVR) and Russia M100(M100) was studied by mixture viscosimetry with the colloidal stability parameters of 0.802 and 0.287, respectively. The coke performance of these two residuums was also studied and found that the coke ratios of LHVR and M100 were respectively 28.40% and 11.05% when reacting under 380 ℃ for 90 minutes, the presence of 0.5% alkaline additive in M100 will reduce the coke ratio to 3.07%. The result shows that there is no close relationship between the colloidal stability of residuum and its coke performance. After the coke formation occurs, the coke rate is mainly decided by Kangs carbon residue. The existence of alkaline additive can change the residuum-disperse-system stability, as a result, the coke rate will be cut down, and the product distribution will also be improved.
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Recycling Process of Industrial Waste Lubricating Oil
HAN Li-jun， REN Ya-lin， WU Tong， GUO Da-guang
2010, 30 (4): 11-14. DOI:10.3696/j.issn.1672-6952.2010.04.004
Abstract ( ) PDF ( 197KB ) ( ) 　　
The refining of industrial waste lubricating oil was investigated with N-methyl-2-pyrrolidone (NMP) and Duo-solvent (ethanolamine and NMP) as solvents, respectively. The preferred refining process is duo-solvent refining under 70 ℃ with 5% ethanolamine, under these conditions the total oil yield was 89.85%. The physical properties of recycled oil is listed as follows: viscosity（40 ℃） 30.89 mm²•s^-1, viscosity（100 ℃） 5.6 mm²•s^-1, viscosity index 120.4, refractive index 1.450, Color 2.0, freezing point -28.8 ℃, flash point 219.6 ℃ and sulfur content 0.057%.
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Influence of Using Structural Packing in Stripping Section of Vacuum Tower on Pull-Out Rate
ZHANG Long, QI Hui-min, LI Bao-zhong
2010, 30 (4): 15-18. DOI:10.3696/j.issn.1672-6952.2010.04.005
Abstract ( ) PDF ( 177KB ) ( ) 　　
Vacuum deep distillation of crude oil is one of representative technology for increasing the yield of light oil. The influence of process parameters in stripping section of vacuum tower on pull-out rate was tested, and the impact of tray or structural packing used in the stripping section of tower on strippin efficiency was disscussed. Furthermore, the coking of structural packing in the stripping section was analyzed. Finally, structural packing in the stripping section showed great impact on enhancing vacuum pull-out tate and would not lead to the coking in the stripping section.
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Pretreatment Process for Lignocellulose by Dilute Hydrochloric Acid
YAO Xiu-qing, YANG Xiang-hua
2010, 30 (4): 19-21. DOI:10.3696/j.issn.1672-6952.2010.04.006
Abstract ( ) PDF ( 191KB ) ( ) 　　
Pretreatment process for lignocellulose by dilute hydrochloric acid was performed and four factors including reaction temperature (θ), reaction time (t), concentration of hydrochloric acid (c), and the ratio of liquid/solid (r) were studied by method of Plackett-Burman design. Finally, the preferred pretreatment conditions are found as follows: t＝1 h，θ＝115 ℃，c＝1％ and r＝10.
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Influence of the Buried Depth to the Soil Temperature -Field Around the Buried Hot Oil Pipeline
LU Qin-li， GU Fu-xin， MA Gui-yang， LI Wei-jun
2010, 30 (4): 22-25. DOI:10.3696/j.issn.1672-6952.2010.04.007
Abstract ( ) PDF ( 612KB ) ( ) 　　
Along long transmission pipeline, geology and hydrology is different, the difference of buried pipeline depth is great. The corresponding natural ground temperature and pipelines-temperature field are also different. If the average or equivalent depth is considered only, the pipeline computation will make a very big error. The use of numerical method will consider the fact that the numerical model approaches the actual frozen earth geological condition and the nonlinear characters, which appears especially important. The limited unit method was used to calculate the soil temperature field around the pipelines by three dimensional numerical compute under the different buried depth conditions. The result indicates that the pipeline temperature change is, to some extent, affected by the buried depth, especially in the frozen earth area, the temperature difference between natural soil and pipelines' surroundings is greater.
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Numerical Simulation of Around Soil Temperature Field of the Parallel Pipeline Trench
YE Dong-wen， WANG Yue， DU Ming-jun， FU Xiao-dong， ZHAO Qing-fu
2010, 30 (4): 26-29. DOI:10.3696/j.issn.1672-6952.2010.04.008
Abstract ( ) PDF ( 736KB ) ( ) 　　
Hot oil pipeline and product pipeline with the parallel in the trench for the laying was studied for energy transfer process. Application of finite difference method analyzed the pipeline during normal operation of non-steady-state heat transfer model. And using finite volume method calculated the pipeline in parallel pipelines at different sections around the soil temperature field in numerical calculation. In the west pipeline, Shanshan-sibao, for example, the surface temperature with periodic boundary conditions, and obtained the discipline in different seasons at different locations along the soil temperature field. Research shows that with the cyclical changes of surface temperature, the impact of cold product pipeline to the soil temperature field around hot oil pipeline is different. And the impact on soil temperature field around the side of hot oil pipeline far away from the cold product pipeline is little. With the run-time increasing of pipeline, the impact of cold product pipeline to the soil temperature field surrounding the hot oil pipeline gradually weakened. Simulation results show that it is consistent with the practice. It provides theoretical guidance for the developing maintenance plans and intermittent delivery programs and determining safe shutdown time.
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Development of the Coding System of the MotorManufactory Parts for DJ-1CAPP[
ZHAO Jie，NIU Hai-shan, GAO Jing-jing
2010, 30 (4): 30-33. DOI:10.3696/j.issn.1672-6952.2010.04.009
Abstract ( ) PDF ( 499KB ) ( ) 　　
According to the particularity and structural characteristics of coal mine products, a 13 classified codification system was developed. A method of part input based on feature surface description was set up, and part automatic coding was implemented in the DJ-1 CAPP system, which provides supports to the standardization and automation of process plan.
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Reliability Calculation of the Opening Reinforcement on Information Entropy and Fuzzy Theory
JIN Zi-ming， LI Wei-chen
2010, 30 (4): 34-37. DOI:10.3696/j.issn.1672-6952.2010.04.010
Abstract ( ) PDF ( 186KB ) ( ) 　　
For random uncertainties and fuzzy uncertainty of the pressure vessel opening reinforcement，based on information entropy theory that fuzzy entropy is equal to probability entropy, the relation formula of the random variables equivalent conversion into fuzzy variables in normal distribution was established. It defined the membership function of the shell hole nominal thickness and the reinforcing pad thickness, determined the fuzziness coefficient, deduced the fuzzy reliability calculating formula of the reinforcing pad circle thickness, and illustrated calculation process.
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Computer Simulation of Microstructure Evolution of Al-Cu Alloy in Near-Liquidus Casting
Zhang Yan-hua， Zhou Zhi-min
2010, 30 (4): 38-41. DOI:10.3696/j.issn.1672-6952.2010.04.011
Abstract ( ) PDF ( 499KB ) ( ) 　　
The models of temperature fields and phase transformation of Al-Cu alloy were developed for its near liquidus semi-continuous casting by a multi-scale simulation method，where the change in, solid fraction is available to couple the macro-scale simulation with meso-scale one．The solidifying process of Al- Cu alloys of Cu content of 4％, 4.5% and 5% was simulated during near-liquidus casting at by using finite difference method and cellular automata method at pouring temperature of 7~25 K higher than liquidus temperature, casting speed of 1.5~3.5 mm/s and cooling coefficient of 1 000~2 000 W/（m2•K）. The result is consistent with experimental. the content of alloying elements has great influence on the semisolid microstructure formation．The calculation results showe that microstructure are fine, uniform and near globular when the mass fraction of Cu is 5％, pouring temperature is 930 K, cooling coefficient is 1 000 W/(m2•K) and casting speed is 2 mm/s．
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Numerical Analyzed of Layer Roll Vaporization -Process in LNG Spherical Tank
LI Xia，MA Gui-yang，DU Ming-jun，CHEN Zhong-hua，SU Kai，GAO Xue-li
2010, 30 (4): 42-44. DOI:10.3696/j.issn.1672-6952.2010.04.012
Abstract ( ) PDF ( 455KB ) ( ) 　　
The process of LNG rolling evolution was simulated after stratification according to control equation of the process of rolling in LNG spherical tank, based on VOF model and boussinesq. Numerical analysis of the affecting factors for the roll. Research shows that the root cause of rolling for LNG is layering. The average convection velocity increased in the tank is followed with increasing of the quantity of environment heat leakage, accelerated the roll time of LNG. LNG rolling time could be lag because of large differences density in layered area but natural convection is severe within the layer. Roll will get the evaporation rate gather in the lower then caused the pressure augment and serious harm in the tank in a moment. Finally, some suggestions to prevent rolling were given. Providing theoretical guidance for LNG safety storage and optimize operations.
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Control System of Water Supply Valve of Waterworks Based on the HMI and PLC
LI Wei-jun， LU Qin-li， WANG Bo
2010, 30 (4): 45-46. DOI:10.3696/j.issn.1672-6952.2010.04.013
Abstract ( ) PDF ( 295KB ) ( ) 　　
A simple control method of aiming at the control issue of water supply valves in the pipes of waterworks based on the HMI and PLC was represented. Under the circumstances that do not need install the servo mechanism and replace the valve, implementing the remote control of valve utilizing the ordinary AC single-phase motor as the power and designing a kind of detecting mechanism of cylinder number of valve based on the optical switch. It has the characteristics of low cost and high reliability，which has more extended and applied value on the frequently-adjusting valves of waterworks.
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Numerical Simulation of Three-Dimensional Unsteady-State Heat Transfer for Buried Hot Oil Pipeline at Shutdown
XU Dan， SHEN Long-she， DU Ming-jun， CHEN Zhong-hua
2010, 30 (4): 47-50. DOI:10.3696/j.issn.1672-6952.2010.04.014
Abstract ( ) PDF ( 702KB ) ( ) 　　
For the research of buried hot oil pipelines at shutdown, it was established that normal operation of buried hot oil pipelines and unsteady-state heat transfer model at shutdown with finite volume method and finite difference method. It considered that the changes of crude oil viscosity, density, specific heat and thermal coefficient with temperature in normal operation and shutdown, and considered oil latent heat of solidification impact on temperature drop at shutdown. Land surface temperature bases on periodic boundary conditions. And temperature drop of hot oil pipelines which are put into operation and has been operating until the march of the second year was simulated at shutdown. The research shows that there are many differences about oil curing at each section of pipeline and temperature field of soil obviously changes with shutdown time prolonged. Shutdown time is reasonably made sure, which provides theoretical guidance for pipe safe start.
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Fuzzy C-Means Clustering Algorithm With Spatial Information for Image Segmentation
LI Li－jun
2010, 30 (4): 51-53. DOI:10.3696/j.issn.1672-6952.2010.04.015
Abstract ( ) PDF ( 234KB ) ( ) 　　
The conventional fuzzy C means clustering algorithm couldn't consider any spatial information, and it is no good to noise image segmentation. In order to overcome this shortcoming, a fuzzy C-means clustering algorithm using spatial information for image segmentation was proposed. The new algorithm could make full use of pixels neighborhood feature by improving the membership function, furthermore local information and non local information were introduced in dissimilarity of data and clustering center. Experimental results show that this method is effective in image segmentation, and has better performance of resisting noise.
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Checking the Bone Density by Medical Image Based on Alternate Pattern of Random Walk
ZHANG Ling-yu, JI Yu-bo
2010, 30 (4): 54-58. DOI:10.3696/j.issn.1672-6952.2010.04.016
Abstract ( ) PDF ( 455KB ) ( ) 　　
A kind of method with using of vertebra medical image to deal with image key data was presented. First, used of the method of piecewise linear transform to stretch gray level of image for enhancing contrast ratio between target area and background area or reducing the detail in the target area. Second, used of information of pixel gray level to set up weighing chart, choose target seed pixels and background seed pixels, and then make use of rand-walk algorithm to divide up image so that receive edge of contour line. At last, unit area pixel average gray-level in the range of edge contour line was computed. Through comparing gray value of unit area in the region with bone density which can be gotten from physic testing, the bone density may be received in the checked region.
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Designing of Student Examination Card System by Excel,VB
SONG Yun-Feng
2010, 30 (4): 59-62. DOI:10.3696/j.issn.1672-6952.2010.04.017
Abstract ( ) PDF ( 466KB ) ( ) 　　
In order to address process big the data volume, big work volume, processing data from the repeated and higher labor-intensive problems in examination card production, used of Excel, Word in Office software and visualization programming software Visual Basic 6.0 to develop the data processing system - student test card production system which is simple and fast data processing and has good versatility. By Excel to collect, collate data, produce documents using Word templates, using VB as a compilation tool to Excel, the standard data and directories stored photo data output as a standard Word document to prepare for print output, or archived. After the actual use of the system, the means to enhance the work efficiency, solve work problems.
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Application of Embedded Database in Data Mining System
LIU Yang, YU Chen-yun, ZHANG Xue-jun
2010, 30 (4): 63-65. DOI:10.3696/j.issn.1672-6952.2010.04.018
Abstract ( ) PDF ( 179KB ) ( ) 　　
The embedded database is a new database technology. It was created along with the development of Web technology, business intelligent technology and mobile computing technology. The reason why data mining system used embedded database was analyzed. Derby database was made into a separate Eclipse plug-in unit and the unit was applied to data mining system in order to meet the specific needs. The application of embedded database used in data mining system not only addresses the data management issues, but also ensures the portability of the system.
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Inter-Turn Stator Winding Fault Detection in Synchronous Generator
LI Xiao-dan
2010, 30 (4): 66-72. DOI:10.3696/j.issn.1672-6952.2010.04.019
Abstract ( ) PDF ( 716KB ) ( ) 　　
The inter-turn stator winding fault of synchronous generator, which is common and destructive, greatly affects the security of the generator and the power network. Based on the extended Park vector approach(EPVA), a practical method of reference frame conversion—the extended alpha beta method, was proposed, and the unsymmetric voltage and current caused by the inter-turn stator winding fault in generator was analyzed by this new method. Then the graphical representation and digital characteristic of fault is obtained. This method is reliable and easy to be applied into practice. And it is a noninvasive approach to detect the inter-turn stator winding fault. The dynamic simulative experiment results with different load, demonstrate the effectiveness of the proposed technique. Combined with multi-loop method, this can be applied to the on-line detection and location of inter-turn short circuits in the stator windings of three-phase synchronous generator as a new method. 
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Adaptive Fault Tolerant Control for a Class of Inherent Nonlinear Systems
CHU Jun-xia
2010, 30 (4): 72-75. DOI:10.3696/j.issn.1672-6952.2010.04.020
Abstract ( ) PDF ( 187KB ) ( ) 　　
It considered the actuator fault tolerant control and accommodation problem for a class of inherent nonlinear system with unknown time-varying virtual control coefficients, uncertain time-varying nonlinear parameters and uncontrollable unstable linearization, by employing the homogeneous system theory and the adding a power integrator design.The actuator fault was accommodated by an adaptive controller based backstepping approach, so as to ensure identical (stabilizable) behaviour of the healthy of the faulty system. Simulation results of a numerical example demonstrate good performance of the proposed approach .
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M-ssbauer Spectra ofCo68.15Fe4.35Si12.5B15 by Low Frequency Pulse Magnetic Field
ZHANG Lei， GUO Hong
2010, 30 (4): 76-79. DOI:10.3696/j.issn.1672-6952.2010.04.021
Abstract ( ) PDF ( 251KB ) ( ) 　　
Amorphous alloys ofCo68.15Fe4.35Si12.5B15  were treated by low frequency pulse magnetic field．The microstructure changes of amorphous specimens before and after treatment were observed by Mssbauer spectra and TEM．The results show that the nanocrystallization of amorphous alloy ofCo68.15Fe4.35Si12.5B15  can occur at low frequency pulse magnetic field．The precipitation content of the nanocrystalline phase α-Fe(Si) with bcc crystal structure is about 2.743％~23.960％，the grain size is 2~10 nm，and the quantity of crystallization have relation with the magnetic field intensity and pulse frequency.
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Implementation of Local Discontinuous Galerkin Method for Poisson Equations on Unstructured Meshes
ZHANG Rong-pei, SONG Dai-cai, MENG Ling-chang
2010, 30 (4): 80-84. DOI:10.3696/j.issn.1672-6952.2010.04.022
Abstract ( ) PDF ( 397KB ) ( ) 　　
The local discontinuous Galerkin (LDG) method using to solve poisson equations on two-dimensional domain was introduced. The construction of LDG was described. The algorithm formulation and practical implementation with linear elements and quadratic elements were discussed in triangular element cases, including numerical quadrature rules, mass matrix formula and iterative methods to solve system. At last, numerical experiments were presented to verify the accuracy of convergence.
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Stability of Population Model With Delay for a Single-Species With Harvesting
TENG Yong， LI Shi-tao
2010, 30 (4): 85-87. DOI:10.3696/j.issn.1672-6952.2010.04.023
Abstract ( ) PDF ( 340KB ) ( ) 　　
One of the most interesting topics in ecology systems is the stability of species. The delay population model for a single-species with harvesting was considered. Local stability was given by demark ramification. The curve of population which changes by time was given by numerical simulation, and adequate control of harvesting capacity causes the single-species in stability states.
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Improved Particle Swarm Optimization Method for Estimating the Parameters of Logistic Curve
LIU Guo-zhi, HE Peng-qing
2010, 30 (4): 88-90. DOI:10.3696/j.issn.1672-6952.2010.04.024
Abstract ( ) PDF ( 129KB ) ( ) 　　
It makes further research on estimating the parameters of logistic curve on based of the present document, and an improved method for estimating the parameters of logistic curve-improved particle swarm optimization method was presented. It does not require gradient computation, and intends to produce faster and more accurate convergence. The sampling calculation shows that parameter estimation method is higher precise.
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Evaluation on Innovation Capability of Every Provinces in Our Country Based on Principal Component Analysis
LI Qing-dong, NIU Jing
2010, 30 (4): 91-96. DOI:10.3696/j.issn.1672-6952.2010.04.025
Abstract ( ) PDF ( 253KB ) ( ) 　　
The main carriers of national innovation capacity are the provinces which gather the technological, economic, and cultural, and the strength of provincial innovation capacity indicates the strength of the national innovation capability. So the key to the improvement of the national innovation capacity is to enhance the innovation capacity of each province. Using the statistical software SPSS Statistics, the statistics with principal component analysis method was analyzed, and also the innovation capability for our countrys on 31 provinces and municipalities was analyzed and sorted. According to evaluate results, the policy recommendations related to provide better ideas for economic development of each province was put forwarded.
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Application of Gray Relational Analysis Method and General Grading Method in the Projects Bidding Evaluation
ZHANG Chun-shu
2010, 30 (4): 97-. DOI:10.3696/j.issn.1672-6952.2010.04.026
Abstract ( ) PDF ( 169KB ) ( ) 　　
China s construction project mean tender methods include reasonable low price bid evaluation, general grading method and tow-stage evaluation method etc.. These evaluation index systems were proved to be effective and feasible. However, some of them need to qualitative evaluation score; it is inevitably arbitrary and artificial factors. A mathematic model based on fussy mathematics and gray relational analysis was used to construct a comprehensive evaluation index system and to build a simple and effective practical model. Provided valuable theoretical basis for choose the successful bidder.
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