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Volume 10 No. 5
20 May 2005
Ternary Diffusion Coefficients of 1-Hexanol-Hexane-Toluene and 1-Propanol-Water-Ethylene Glycol by Taylor Dispersion Method

Zhongqi Ren, Weiyang Fei, Bart Hans-Joerg

2005, 10(5): 523-528.   doi:10.1016/S1007-0214(05)70112-7
Abstract ( 157 )  ( 412 )   Save
The Taylor dispersion method was used to measure diffusion coefficients of three-component liquid systems. An improved constrained nonlinear least-square method was used to evaluate the ternary diffusion coefficients directly by fitting the mathematical solutions of the dispersion equation to eluted solute peaks detected using a differential refractometer. Diffusion coefficients of the three-component system of acetone-benzene-CCl4, determined at 25°C, were used to test the procedure. The measur...
Rapid Cloning and Expression of Glutaryl-7-Aminocephalosporanic Acid Acylase Genes from Soil Samples

Hui Luo, Huimin Yu, Qiang Li, Zhongyao Shen

2005, 10(5): 529-534.   doi:10.1016/S1007-0214(05)70113-9
Abstract ( 164 )  ( 376 )   Save
A polymerase chain reaction (PCR)-based strategy was developed to rapidly obtain the gene encoding for an industrially important enzyme, glutaryl-7-aminocephalosporanic acid (GL-7-ACA) acylase. Different soil samples were cultured with a Pseudomonas selective medium to enrich specific microorganisms, and then the genomic DNA was extracted to serve as PCR templates. PCR primers for GL-7-ACA acylase gene amplification were designed on the basis of bioinformatics searches and analyses. The method w...
Preparation and Adsorption Ability of Polysulfone Microcapsules Containing Modified Chitosan Gel

Fei Chen, Guangsheng Luo, Weiwei Yang, Yujun Wang

2005, 10(5): 535-541.   doi:10.1016/S1007-0214(05)70114-0
Abstract ( 216 )  ( 424 )   Save
Chemically modified chitosan beads containing polyethyleneimine (PEI) were prepared to improve the metal ion adsorption capacity of the chitosan beads and their mechanical stability and to limit their biodegradability. The modified beads were encapsulated with the polymer material polysulfone by a novel surface coating method named the emulsion phase inversion method. The adsorption properties of the modified beads and the microstructures of the polysulfone coating layer were then analyzed. The ...
Transdermal Delivery of Piroxicam by Surfactant Mediated Electroporation

Jia Zan, Guoqiang Jiang, Ying Lin, Fengping Tan, Fuxin Ding

2005, 10(5): 542-547.   doi:10.1016/S1007-0214(05)70115-2
Abstract ( 181 )  ( 398 )   Save
A lipophilic, nonsteroidal antiinflammation drug, piroxicam, was administered by skin electroporation using short, high-voltage pulses. The transdermal delivery of piroxicam during the electroporation was buffered due to the higher partition in skin lipids than in aqueous environments, which is called entrapment. Entrapment is the main resistance to transdermal delivery of lipophilic drugs. Two types of surfactants were used to enhance the skin electroporation. Tween 80 (0.2 g/L) and sodium dode...
Prediction of Solid-Liquid Equilibrium for KCl in Mixed Water-Ethanol Solutions Using the LIQUAC Model

Yangzheng Lin, Jiding Li, Chuyi Zeng, Cuixian Chen

2005, 10(5): 548-553.   doi:10.1016/S1007-0214(05)70116-4
Abstract ( 184 )  ( 409 )   Save
The LIQUAC model is often used to predict vapor-liquid equilibria, osmotic coefficients, and mean ion activity coefficients for electrolyte systems. This paper describes a thermodynamic method to analyze solid-liquid equilibrium for electrolytes in mixed solvents solutions using the LIQUAC model. The KCl solubilities in mixed water-ethanol solutions are predicted with the LIQUAC model and its original interaction parameters. This method is also used to obtain new K+-ethanol interaction parameter...
Tin Oxide and Carbon Composite (Sn6O4(OH)4 /AG) as the Anode in a Lithium Ion Battery

Kezhi Lin, Xiaolin Wang

2005, 10(5): 554-560.   doi:10.1016/S1007-0214(05)70117-6
Abstract ( 185 )  ( 391 )   Save
A tin oxide and carbon composite (Sn6O4(OH)4/AG) with a Sn content of 0.15–0.30 was prepared by chemical deposition at normal pressures and temperatures. The structures of the artificial graphite (AG), the Sn6O4(OH)4, and the Sn6O4(OH)4/AG were analyzed using X-ray diffraction. The electrochemical lithiation was investigated by measuring the galvanostatic charge and discharge ratio. The electrochemical capacities of the three materials during the first discharge were 310 mAh/g (AG), 616 mAh/g (S...
Prediction of Liquid-Liquid Equilibrium Using the Group Solubility Parameter Model

Mo Zhao, Fuming Chen

2005, 10(5): 561-566.   doi:10.1016/S1007-0214(05)70118-8
Abstract ( 214 )  ( 407 )   Save
The group solubility parameter (GSP) model was used to analyze the liquid-liquid equilibrium (LLE) of ternary and quaternary systems. The GSP parameters are divided into four dimensions representing the four major intermolecular forces. The values of the parameters were determined by regression using the nonlinear SIMPLEX optimization method to fit the LLE data of 548 ternary and 26 quaternary systems selected from the literature. LLE predictions of 8 ternary systems were then made using the fit...
Crocin Synthesis Mechanism in Crocus sativus

Bo Yang, Zhigang Guo, Ruizhi Liu

2005, 10(5): 567-572.   doi:10.1016/S1007-0214(05)70119-X
Abstract ( 252 )  ( 378 )   Save
Saffron (Crocus sativus) cells can synthesize crocin, crocetin digentiobiosyl ester, in suspension cultures. The crocin family biosynthesis mechanism was studied using high pressure liquid chromatography (HPLC) to determinate the glucosyltransferase activity and to develop a method for synthesizing medicine from saffron cells. Previous studies indicated that two glucosyltransferases might be involved in the formation of crocetin glucosyl- and gentiobiosyl-esters. GTase1 formed an ester bond betw...
Morphological Transformation of Plant Cells in vitro and Its Effect on Plant Growth

Zhigang Guo, Zhaolin Zeng, Ruizhi Liu, Ying Deng

2005, 10(5): 573-578.   doi:10.1016/S1007-0214(05)70120-6
Abstract ( 189 )  ( 387 )   Save
Enhancement of cell growth in suspension cultures is urgently needed in plant cell culture engineering. This study investigates the relationship between morphological transformation and cell growth in callus and suspension cultures of saffron cells belonging to the cell line C96 induced from Crocus sativus L. In the suspension culture, an unbalanced osmotic pressure between the intracell and extracell regions induced a large morphological transformation which affected normal division of the saff...
Weak-Keys in Public Key Cryptosystems Based on Discrete Logarithms

Suiyan Tai, Ping Luo, Xiaoning Peng, Daoshun Wang

2005, 10(5): 579-581.   doi:10.1016/S1007-0214(05)70121-8
Abstract ( 166 )  ( 387 )   Save
The discrete logarithm method is the foundation of many public key algorithms. However, one type of key, defined as a weak-key, reduces the security of public key cryptosystems based on the discrete logarithm method. The weak-key occurs if the public key is a factor or multiple of the primitive element, in which case the user's private key is not needed but can be obtained based on the character of the public key. An algorithm is presented that can easily test whether there is a weak-key in the ...
Multivariate Statistical Process Monitoring Using Robust Nonlinear Principal Component Analysis

Shijian Zhao, Yongmao Xu

2005, 10(5): 582-586.   doi:10.1016/S1007-0214(05)70122-X
Abstract ( 173 )  ( 426 )   Save
The principal component analysis (PCA) algorithm is widely applied in a diverse range of fields for performance assessment, fault detection, and diagnosis. However, in the presence of noise and gross errors, the nonlinear PCA (NLPCA) using autoassociative bottle-neck neural networks is so sensitive that the obtained model differs significantly from the underlying system. In this paper, a robust version of NLPCA is introduced by replacing the generally used error criterion mean squared error with...
Image Reconstruction Using a Genetic Algorithm for Electrical Capacitance Tomography

Changhua Mou, Lihui Peng, Danya Yao, Deyun Xiao

2005, 10(5): 587-592.   doi:10.1016/S1007-0214(05)70123-1
Abstract ( 197 )  ( 410 )   Save
Electrical capacitance tomography (ECT) has been used for more than a decade for imaging dielectric processes. However, because of its ill-posedness and non-linearity, ECT image reconstruction has always been a challenge. A new genetic algorithm (GA) developed for ECT image reconstruction uses initial results from a linear back-projection, which is widely used for ECT image reconstruction to optimize the threshold and the maximum and minimum gray values for the image. The procedure avoids optimi...
Implementation of Direct Torque Control Scheme for Induction Machines with Variable Structure Controllers

Jian Li, Geng Yang, Huan'gang Wang, Wenli Xu

2005, 10(5): 593-597.   doi:10.1016/S1007-0214(05)70124-3
Abstract ( 173 )  ( 418 )   Save
A torque control scheme for high-performance induction machine drives was developed to overcome some disadvantages of direct torque control (DTC). In the improved DTC method, the stator flux and the torque controllers use variable-structure control theory which does not require information about the rotor speed. Space vector modulation is applied to the voltage source inverter to reduce the torque, stator flux, and current ripples. The digital signal processor-based implementation is described i...
On-Line Partial Discharge Monitoring and Diagnostic System for Power Transformer

Du Lin, Lei Jiang, Fuqi Li, Deheng Zhu, Kexiong Tan, Chengqi Wu, Xianhe Jin, Changchang Wang, T.C. Cheng

2005, 10(5): 598-604.   doi:10.1016/S1007-0214(05)70125-5
Abstract ( 292 )  ( 403 )   Save
This paper introduces a computerized on-line partial discharge (PD) monitoring and diagnostic system for transformers. The system, which is already in use in a power station, uses wide-band active transducers and a data acquisition unit with modularized and exchangeable components. The system software is a power equipment monitoring and diagnostic system, which is based on the component object model, and was developed for monitoring multiple parameters in multiple power supply systems. The stati...
Iterative Method for Constructing Complete Complementary Sequences with Lengths of 2mN

Chao Zhang, Chenggao Han, Yiting Liao, Xiaokang Lin, Mitsutoshi Hatori

2005, 10(5): 605-609.   doi:10.1016/S1007-0214(05)70126-7
Abstract ( 230 )  ( 390 )   Save
Complete complementary sequences are widely used in spectrum spread communications because of their ideal correlation functions. A previous method generates complete complementary sequences with lengths of NnN(n,N∈Z+). This paper presents a new iterative method to construct complete complementary sequences with lengths of 2m N(M,N∈Z+). The analysis proves that this method can produce many sequence sets that do not appear in sequence sets generated by the former method, especially shorter sequenc...
Advanced ECU Software Development Method for Fuel Cell Systems

Shuo Tian, Yuan Liu, Wenchuan Xia, Jianqiu Li, Minggao Yang

2005, 10(5): 610-617.   doi:10.1016/S1007-0214(05)70127-9
Abstract ( 176 )  ( 383 )   Save
The electronic control unit (ECU) in electrical powered hybrid and fuel cell vehicles is exceedingly complex. Rapid prototyping control is used to reduce development time and eliminate errors during software development. This paper describes a high-efficiency development method and a flexible tool chain suitable for various applications in automotive engineering. The control algorithm can be deployed directly from a Matlab/Simulink/Stateflow environment into the ECU hardware together with an OSE...
Numerical Investigation of Fire Smoke Transport in the Tsinghua University Sports Center

Jianguo Chen, Haixin Chen, Song Fu

2005, 10(5): 618-622.   doi:10.1016/S1007-0214(05)70128-0
Abstract ( 188 )  ( 387 )   Save
Fire Dynamics Simulator v3.0 was used to investigate and assess fire smoke transport and management in a realistic indoor sports center. An atrium fire test case illustrated the code's superiority over code-type empirical models for both accuracy and capability. Four fire scenarios in the Tsinghua University Sports Center were then simulated. The smoke layer's descent speed was predicted for each case. The importance of the door effect was revealed and an additional mechanical ventilation system...
Analysis of Alignment Influence on 3-D Anthropometric Statistics

Xiuwen Cai, Zhizhong Li, Chien-Chi Chang, Patrick Dempsey

2005, 10(5): 623-626.   doi:10.1016/S1007-0214(05)70129-2
Abstract ( 199 )  ( 407 )   Save
Three-dimensional (3-D) surface anthropometry can provide much more useful information for many applications such as ergonomic product design than traditional individual body dimension measurements. However, the traditional definition of the percentile calculation is designed only for 1-D anthropometric data estimates. The same approach cannot be applied directly to 3-D anthropometric statistics otherwise it could lead to misinterpretations. In this paper, the influence of alignment references o...
Fuzzy Multiple Attribute Decision Making for Evaluating Aggregate Risk in Green Manufacturing

Hua Liu, Weiping Chen, Zhixin Kang, Tungwai Ngai, Yuanyuan Li

2005, 10(5): 627-632.   doi:10.1016/S1007-0214(05)70130-9
Abstract ( 268 )  ( 374 )   Save
Industrial risk and the diversification of risk types both increase with industrial development. Many uncertain factors and high risk are inherent in the implementation of new green manufacturing methods. Because of the shortage of successful examples and complete and certain knowledge, decision-making methods using probabilities to represent risk, which need many examples, cannot be used to evaluate risk in the implementation of green manufacturing projects. Therefore, a fuzzy multiple attribut...
Economics and Performance Forecast of Gas Turbine Combined Cycle

Xiaotao Zhang, Hideaki Sugishita, Weidou Ni, Zheng Li

2005, 10(5): 633-636.   doi:10.1016/S1007-0214(05)70131-0
Abstract ( 186 )  ( 406 )   Save
Forecasts of the economics and performance of gas turbine combined cycle (GTCC) with various types of gas turbines will help power plant designers to select the best type of gas turbine for future Chinese powerplants. The cost and performance of various designs were estimated using the commercial software GT PRO. Improved GTCC output will increase the system efficiency which may induce total investment and will certainly increase the cumulative cash which then will induce the cost and the paybac...
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