Journal of South China University of Technology(Natural Science Edition)

Preparation and Properties of Bagasse Fibre-Molding Decorative Building Material

Han Wen-jia Chen Ke-fu Yang Ren-dang Yang Fei Huang Liang-hui Gao Wen-hua

2011, 39(3): 1-7. doi:10.3969/j.issn.1000-565X.2011.03.001

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Molding decorative building material with excellent physical performances was prepared from natural bagasse fibers via the hot forming process of fiber molding.Then,based on the tensile test,TGA and FT-IR analysis,the factors affecting the mechanical properties of the material were investigated.The results indicate that the tensile performance of the material is mainly affected by the dosages of flame retardant and reinforcing agent,the drying temperature,the drying time and the pressure,that,with the increase of flame retardant dosage,the tensile perfor-mance greatly degrades,that the optimal drying temperature and time are respectively determined as 160℃ and 4min,and that,in a certain pressure range,the tensile performance improves with the drying pressure at an optimal value of 30kN.Moreover,it is found from TGA and FT-IR analysis that,as there is no obvious thermal decomposition and chemical structure change of bagasse fibers during the preparation,the microstructure of the prepared material plays an important role in the tensile performance.In addition,the surface microstructure of the material was analyzed by means of SEM and AFM.

Simultaneous Module-Based Optimization of Operation Parameters of Dryer Section in Paper Machine

Li Yu-gang Liu Huan-bin Li Ji-geng Tao Jin-song Lin Zhi-zuo

2011, 39(3): 8-12. doi:10.3969/j.issn.1000-565X.2011.03.002

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In this paper,by analyzing the characteristics of the energy system of the dryer section in paper machines,a nonlinear programming（NLP） model of the system energy is established,and the corresponding optimization method is proposed.In the method,the dryer section is divided into several functional modules,and the process model of each module is set up based on material and energy balance.By using the operation parameter ranges as the constraints and by taking the minimum energy consumption per unit product as the objective,the ope-ration parameters corresponding to the minimum energy consumption are determined with the help of the algorithm presented in Matlab.It is found that the proposed NLP model is well adaptive and convenient for the energy optimization at different operation parameters,concretely,for newsprint machines,the energy consumption in the dryer section reduces by about 6%.

Numerical Simulation of Flow Characteristics in Rectangular Tapered Pulp Distributor

Liu Wei Chen Ke-fu Li Jun

2011, 39(3): 13-16,27. doi:10.3969/j.issn.1000-565X.2011.03.003

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In order to reveal the flow characteristics of fluid in rectangular tapered pulp distributor,the velocity and pressure distributions in the rectangular tapered header as well as the mass flowrate distribution out of manifold tubes were investigated based on computational fluid dynamics.Then,three kinds of rectangular tapered headers respectively in simplified type,piecewise approximated type and modified type were comparatively investigated.The results show that there are distinct velocity nonuniformity and pressure gradient along the flow direction in the widely-used simplified header,which results in nonuniform mass flowrate out of the manifold tubes,and that the pressure and the mass flowrate in both the approximated the modified headers are also obviously nonuniform.It is also found that and the mass flowrate distributions in the three headers,which has notable deviation from the expected ones,increase in the order of simplified typepiecewise approximated typemodified type,and that the back wall shape of the rectangular tapered header designed based on the Baines method is greatly different from the expected one.

Extraction of Molybdenum and Rhenium from Electro-oxidation Lixivium of Molybdenite

Cao Zhan-fang Zhong Hong Jiang Tao Qiu Zhao-hui Liu Guang-yi

2011, 39(3): 17-21. doi:10.3969/j.ssn.1000-565X.2011.03.004

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The electro-oxidation is an environment-friendly hydrometallurgy technique of extraction from molybde-nite concentrate,with moderate reacting conditions and high metal recovery.In this paper,aiming at the key step of the technique,namely the separation of Mo（Ⅵ） and Re（Ⅶ）,some experiments were performed.The results show that,when the mixture of 30% N235＋20% sec-caprylic alcohol＋50% kerosene oil is used as the extractant for the extraction with a W/O ratio of 1∶2 and an acidity of 59g/L HCl at room temperature,the single-stage extraction rates of Mo（Ⅵ） and Re（Ⅶ） respectively reach 99.95% and 95.76%;and that,when 17% ammonia is used as the stripping agent for the stripping with a W/O ratio of 2∶1 at room temperature,the stripping rates respectively reach 99.49% and 98.35%.

Structure and Properties of Crosslinked Potato-Carboxymethyl Starch

Zhong Zhen-sheng Zhong Yan-ping Sun Ang

2011, 39(3): 22-27. doi:10.3969/j.issn.1000-565X.2011.03.005

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Crosslinked carboxymethyl starch（CCMS） was synthesized from potato starch,with epichlorohydrin as the crosslinking agent.Then,the properties of CCMS were compared with those of native potato starch,crosslinked starch（CS）,carboxymethyl starch（CMS） and carboxymethyl cellulose（CMC）,finding that CCMS paste is of excellent aging resistance,thermal stability,pH stability and shear stability.Moreover,the molecular structure and particle morphology of potato starch and the modified starches were characterized by means of FT-IR,ESEM and XRD,with the modification degree and the relationship between structure and properties being also analyzed.The results indicate that CCMS is of reasonable structure and excellent

Virtual Screening of Anti-Diabetes Ⅱ Active Components in Psidium guajava Leaves

Liu Mei-feng Jiang Li-rong Liu Hua-nai Lin Jing-qun

2011, 39(3): 28-31,36. doi:10.3969/j.issn.1000-565X.2011.03.006

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The extractives from Psidium guajava leaves are of significant function of reducing blood sugar level,but the corresponding active components and mechanism are still unknown.In this paper,CDOCKER module of Discovery Studio 2.1 version was used to reveal the anti-diabetes Ⅱ mechanism of the extractives from Psidium guajava leaves.In the investigation,PTPIB,PPARγ,α-amylase and α-glycosidase were used as anti-diabetes targets in drug design,and 32 active components with low relative molecular mass,mainly including triterpenoid saponins,flavonoids and tannin compounds,were used as ligands.Then,the virtual screening of these ligands was carried out through molecular docking and scoring judgment to evaluate the combination mode and affinity between the li-gands and the targets.The results show that there is high binding activity between flavonoids/tannins and PTPIB/PPARγ,that both the hydrophobic and the hydrogen bonds play an important role in the molecular combination.It is thus concluded that the introduction of hydrophobic groups in the structure modification of active components may increase their binding affinity to PTPIB and PPARγ.

Preparation and Performances of Novel Sulfonate Polyurethane Surfactants

Lin Dong-en Hu Shou-yin Zhang Yi-wei

2011, 39(3): 32-36. doi:10.3969/j.issn.1000-565X.2011.03.007

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Four kinds of waterborne macromolecular sulfonate polyurethane surfactants（PUS） were synthesized via the acetone method with prepolymerization and chain extension,with toluene diiosocynate（TDI）,polyether glycol（PEG1000,PEG2000,PEG6000,PE6200） and self-prepared sulfonate diamine chain extender as raw materials.Then,the structures of the products were characterized by means of FT-IR,and the surface tension,critical micelle concentration（CMC）,emulsifying property and foaming property were investigated.The results show that the product with PEG as the substrate is of a CMC of about 20g/L,and the corresponding surface tension reaches 41.6mN/m,while that with PE6200 as the substrate is of a CMC of less than 1g/L and a surface tension of 32mN/m.

Synthesis and Properties of Polyester/SiO_2/Silicone Composite Coating

Zhu Zai-sheng Tu Wei-ping Hu Jian-qing

2011, 39(3): 37-41. doi:10.3969/j.issn.1000-565X.2011.03.008

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First,transparent SiO2/silicone resin was prepared by means of the sol-gel method,with tetraethoxysilane and organosiloxane as the raw materials.Then,polyester/SiO2/silicone hardcoat composite films were synthesized on polycarbonate（PC） via the condensation between SiO2/silicone resin and polyester.Finally,the effect of SiO2/silicone resin-to-polyester ratio on the properties of the composite coating was discussed,and the structure and properties of the composite coating were characterized by means of FT-IR,TGA,AFM,SEM,UV spectroscopy and XRD,etc.The results show that the composite with structure is obtained due to the co-condensation between the ethoxy groups in SiO2/silicone resin and the hydroxyl groups in polyester,that the composite coating which is an SiO2/silicone resin mass fraction ranging from 75% to 83% and a storage period of more than ten months,possesses good stability,and that the composite film after the thermal curing,which is smooth and amorphous,improves the transparency of PC sheet,with an adhesion strength to PC sheet of 0 grade and a pencil hardness of 2H.Moreover,it is indicated that the composite film is of excellent thermal stability gradually increasing with the SiO2/silicone resin dosage.

Unsteady Heat Transfer of Porous Media Solar Receiver

Xu Chang Liu De-you Zhen Yuan Guo Su Yan Yan

2011, 39(3): 42-46,51. doi:10.3969/j.issn.1000-565X.2011.03.009

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In order to analyze the unsteady heat transfer characteristics of solar porous media power tower receiver,first,unsteady heat transfer models are established.Then,a volumetric convective heat transfer coefficient model suitable for the receiver is proposed based on the least squares method.Finally,the models are solved by numerical method to analyze the typical unsteady dimensionless temperature field,and to further reveal the influences of the average particle diameter,the porosity,the thickness and the air inlet velocity on the unsteady dimensionless temperature distribution.The results show that porous media with small particles,low porosity,low thickness and high air inlet velocity benefit the reduction of thermal stress-induced destruction.

Modeling and Numerical Analysis of Internal Enhanced Direct Thermoelectric Conversion System

Zhang Zheng Xie Xiao-peng Wu Jiang-hong

2011, 39(3): 47-51. doi:10.3969/j.issn.1000-565X.2011.03.010

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In this paper,a system model of direct thermoelectric conversion applicable to project analysis is established,and the structure and mathematical description of the internal enhanced thermoelectric generator are presented.Moreover,the variation trends of convective heat transfer coefficient,temperature and pressure in the generator channel are obtained through the numerical calculation of convection heat transfer and resistance characteristics.The results are finally compared with those of the external thermoelectric generator.Numerical analyses show that the components set in the channel effectively improve the heat transfer area and convection heat transfer coefficient,and that the shape change of the channel cross section may result in lower flow resistance and pressure drop,thus enhancing the thermoelectric conversion properties.

Coordinative Optimal Design of PSS and SVC Based on Trajectory Sensitivity Technique

Liu Ming-bo Huang Yi-long Lin Shun-jiang

2011, 39(3): 52-57,72. doi:10.3969/j.issn.1000-565X.2011.03.011

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Proposed in this paper is a mathematical model to coordinate the parameter optimal design of power system stabilizer（PSS） and static var compensator（SVC）.In this model,the objective function is obtained by weighting both the rotor speed of each generator and the voltage change of the nodes equipped with SVCs,and the inequality constraints are determined as the ranges of PSS and SVC parameters.By calculating the trajectory sensitivities of the rotor speed and voltage change to the control parameters,the gradients of the objective function to PSS and SVC parameters are evaluated,which accelerates the convergence and helps to search the optimal solution.Moreover,by inducing damping power angle oscillation and voltage-reducing factors in the objective function,both the power angle stability and the voltage stability are guaranteed.Simulations in 3-machine 9-bus and 10-machine 39-bus systems show that the proposed method effectively damps low-frequency power oscillation,improves the transient and the small-signal stabilities,and decreases the post-fault voltage fluctuation of the bus.

High-Frequency Micro-Arc Oxidation High Power Supply with Fully Digital Control

Du Gui-ping Xiang E Zhang Wei-lin

2011, 39(3): 58-61. doi:10.3969/j.issn.1000-565X.2011.03.012

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Proposed in this paper is a high-frequency power supply with fully digital control for micro-arc oxidation.The authors introduce the structure and working principle of the system,and describe the design of two-stage full-bridge inverter with PWM for multi-characteristic output in detail.With the adoption of fully-digital DSP control,the system can output multi-characteristic waveforms as desired.Experiment and operation results show that the proposed power supply fully meets the requirements of micro-arc oxidation and is capable of outputting waveforms with variable frequency and amplitude.

Analysis of Static Loss Factors Based on AHP-Gray Relation and GM（1,N） Model

Zhang Yong-jun Shi Hui Liang Jin-zhao Han Peng

2011, 39(3): 62-66. doi:10.3969/j.issn.1000-565X.2011.03.013

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Proposed in this paper is an idea of analyzing the correlation degree between static loss factors and line loss rate through gray relation（GR） with variable weights,and a GM（1,N） model for predicting the line loss rate.In this method,first,the impact weights of various factors on the line loss are determined based on the loss mechanism.Then,the relationships between various factors and the line loss rate are compared via the GR method.Finally,strongly-correlated factors are picked to establish a loss-rate model for the prediction of distribution line loss rate and loss reduction potential due to relevant factor optimization.Case analyses show that both the GR analysis and the prediction is of high accuracy,and that the proposed method requires fewer samples and less computation,so that it provides a useful guidance for the energy-saving evaluation and planning of power network.

Dual-PWM Frequency-Variable Speed Regulation System Based on Direct Power Control

Wang Wan-wei Yin Hua-jie Guan Lin

2011, 39(3): 67-72. doi:10.3969/j.issn.1000-565X.2011.03.014

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Proposed in this paper is a dual-PWM frequency-variable speed regulation scheme based on direct power control,which is used to achieve the four-quadrant operation of the motor,eliminate the harmonic pollution at the grid side and improve the dynamic response of the motor.The scheme is then modeled and simulated in Matlab/Simulink environment.The results indicate that the proposed scheme based on direct power control is superior to that based on direct current control in terms of control simplicity,dynamic and transient response as well as distur-bance rejection ability.

Experimental Investigation into Small-Scale Jet Diffusion Flame Structure

Gan Yun-hua Song Jing-dong Yang Ze-liang Jiao Ming-lun Zheng Hao

2011, 39(3): 73-77. doi:10.3969/j.issn.1000-565X.2011.03.015

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Comparative experiments between small-scale free jet diffusion combustion and the confined jet one were performed from a circular ceramic burner with the inner diameter of 1.0mm,using liquid ethanol as the fuel.A transparent glass tube with an inner diameter of 8.8mm was put outside the ceramic tube to form a confined space.The structure of the flames in steady combustion was then measured with optical visualization method.The results indicate that the free jet diffusion flames are ellipsoidal while the confined ones are tapered,that the length and width of confined jet diffusion flames are both less than those of free jet flames at the same ethanol flowrate,that the mi-xing of fuel and air in confined space is better than that in free space,and that the structure of confined jet di-ffusion flames is more sensitive to the buoyancy.

Modeling Experiment of SNCR Injection Based on Heat Balance Theory

LU Zhi-Min

2011, 39(3): 78-82. doi:10.3969/j.issn.1000-565X.2011.03.016

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Proposed in this paper is a heat balance-based experiment method for the modeling of SNCR（Selective Non-Catalytic Reduction） injection.The experiments are carried out at a 1∶10 410t/h boiler modeling platform,by which the influences of total flowrate,flow velocity,injector number and injection strategy on the mixing effect are investigated.Moreover,the concept of ideal NOx reduction ratio is introduced to quantify the NOx reduction with different injection strategies.The results indicate that the ideal NOx reduction ratio increases from 47% to 58% with the total flowrate and increases by 8% with the flow velocity,and that it varies from 44% to 52% at different injection strategies.Moreover,it is found that ammonia/NO ratio also has a significantly positive effect on the ideal NOx reduction ratio.

Design and Performance Analysis of Poly-Generation System for Methanol Synthesis and Electric Power Generation with Coke Oven Gas as Raw Material

Zhang Xue-lei Chen Hai-ping Wang Song-ling Zhou Lan-xin

2011, 39(3): 83-89. doi:10.3969/j.issn.1000-565X.2011.03.017

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In order to reasonably utilize coke oven gas（COG）,first,a Lurgi gas-phase methanol synthesis system was designed,with COG as the raw material,and the key parameters of the system were obtained by the simulation with Aspen Plus.Next,the performance of gas-steam combined cycle firing COG was calculated and compared with that firing natural gas.Then,a parallel poly-generation system for gas-phase methanol synthesis and electric power generation was designed.Finally,a performance comparison was performed between the designed system and the exi-sting one-product system.The results show that the carbon supplementation before reformer increases the methanol yield and decreases the energy consumption by about 6%,that the net power and thermal efficiency of the combined cycle respectively decrease by 0.87% and 0.91% when substituting COG for natural gas,and that the thermal efficiency of the poly-generation system is about two points of percentage higher than that of the one-product system.Thus,it comes to the conclusion that the proposed poly-generation system with carbon supplementation before reformer is of the highest thermo-economic benefit.

Numerical Simulation of Microscale Laminar-Flow Diffusion Combustion of Liquid Ethanol

Xu Tao Yang Ze-liang Gan Yun-hua

2011, 39(3): 90-94. doi:10.3969/j.issn.1000-565X.2011.03.018

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By taking into consideration the flow and combustion characteristics of liquid ethanol in microscale flow,a reasonable simulation model is selected based on theoretical analysis for the numerical simulation of microscale laminar-flow diffusion cumbustion of liquid ethanol,and the effects of droplet radiation heat transfer and boundary slip on the simulation are analyzed with Fluent. The simulated results are then compared with the measured ones finding that the numerical simulation considering both the droplet radiation heat transfer and the boundary slip is more accurate.

Area Coordinated Control of Traffic Signals Based on Bi-Level Programming Model

Xu Jian-min Shou Yan-fang Lu Kai

2011, 39(3): 95-100,106. doi:10.3969/j.issn.1000-565X.2011.03.019

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Aiming at the traffic signal timing in oversaturted traffic conditions,a bi-level programming（BP） model for the area coordinated control of traffic signals is presented based on the dynamic subarea division,with the maximum total throughput and the minimum delay time of all entrance lanes at each interaction as the objectives.Then,the effects of queue length,entrance traffic volume and phase sequence on the area coordinated control are analyzed,and the constraint formulas describing the relationships among the intersection phase difference,the effective green time and the dynamic traffic volume are established.Finally,the proposed model is solved by using the hybrid optimization strategy of genetic and simulated annealing algorithms,thus improving the reliability and computational effi-ciency of the global optimal solution.Simulated results indicate that the proposed model accords well with the practical situation.

Adaptive Signal Control Model Based on Vehicle Emission

Li Shi-wu Wang Lin-hong Guo Dong Sun Wen-cai Yang Zhi-fa

2011, 39(3): 101-106. doi:10.3969/j.issn.1000-565X.2011.03.020

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In this paper,first,from the viewpoint of reducing the vehicle emission at road intersection,the mechanism how the signal control impacts vehicle emission is analyzed,and the relationship among signal timing,running state and vehicle emission is investigated.Next,according to the effect of running state on the emission,some mo-dels are established to describe the emission respectively in complete-stop,uncompleted-stop and non-stop states.Then,an optimization method of signal timing scheme is proposed by taking the least incremental emission as the objective.Finally,a verification experiment is performed with the real data of a typical intersection in Changchun,China.The results show that the proposed optimization model helps to reduce the vehicle emission by 6.43%.
{Date}: 2011-06-27

Optimal Arrangement of Detectors Based on Correlation of Link Flow

Wang Dian-hai Xu Cheng Qi Hong-sheng Jin Sheng

2011, 39(3): 107-113. doi:10.3969/j.issn.1000-565X.2011.03.021

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Proposed in this paper is an optimal arrangement method of traffic flow detectors based on the correlation of link flow in the road network.In the investigation,first,the number of key links is determined by using the link-path incidence matrix and its dependence on the network scale,the network connectivity,the number of OD pairs and the path number is analyzed.Then,by taking into consideration such factors as path coverage,road grade,road length and road facilities,a multi-objective optimization model for the selection of key links is set up,and a method determining the non-key link flow through the linear combination of key link flow is proposed.Experimental results on Nguyen-Dupuis network show that the proposed method is of good practicability.

A Multi-Interaction History Learning Approach for Coordination of Urban Intersection Agents

Xia Xin-hai Xu Lun-hui

2011, 39(3): 114-119. doi:10.3969/j.issn.1000-565X.2011.03.022

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Proposed in this paper is a multi-interaction history learning approach for the coordination of urban intersection agents.In the investigation,first,each signalized intersection is defined with an Agent controller.Next,a multi-interaction model for urban intersection Agents is built based on the two-person Nash equilibrium game theory to make each intersection Agent to perform multi-interaction learning with its neighbours and to update its mixed strategy according to the utility value of the selected strategy.Then,the iterative interaction learning process of intersection Agents is analyzed by using the parameters such as memory factor δ,learning probability α and local traffic change probability βi at each intersection.A multi-interactive history learning algorithm was constructed.In the proposed algorithm,intersection Agents coordinate by taking into consi-deration all history interactive information（especially the recent one） coming from neighbouring intersection Agents.Finally the effects of parameters δ,α and βi on the algorithm performance is also analyzed by the experiment of traffic signal control at some connected intersections.The results show that the proposed coordinative learning approach is effective.

Classification of Asphalt Mixture Materials Based on X-ray Computed Tomography

Zhang Xiao-ning Duan Yue-hua Li Zhi Wu Wen-liang Wan Cheng

2011, 39(3): 120-124,134. doi:10.3969/j.issn.1000-565X.2011.03.023

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In general,industrial CT images of asphalt mixture are processed via the threshold segmentation to obtain the global threshold for the separation of aggregates from other materials.In order to presents an effective method that comprehensively evaluates the image segmentation of asphalt mixture,the characteristics of image gray histogram distribution are considered,and the Gaussian mixture model（GMM） and the fuzzy C-means（FCM） clustering algorithm for pattern recognition are introduced in the image process.Then,a two-classification strategy is adopted twice to divide the image into four different regions respectively corresponding to background,voids,mastics and aggregates.Moreover,a reference material is produced to calibrate the CT results,and three methods for material classification are used as the auxiliaries for the valuing of reference material to comprehensively compare the computational efficiency and the segmentation effect.The results show that the OTSU method is more efficient than GMM and FCM for the processing of images with clear double-peak distribution because it has no need for improvement.

Permanent Deformation of Asphalt Pavement Under Horizontal Moving Load

Li Ling-lin Huang Xiao-ming

2011, 39(3): 125-129. doi:10.3969/j.issn.1000-565X.2011.03.024

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In order to find the cause of the severe asphalt permanent deformation in such sections as large longitudinal slope,traffic intersections and bus stations,the response of asphalt pavement to horizontal moving load is calculated with ABAQUS and its subroutine UTRACLOAD and DSLOAD.The results show that the vertical permanent deformations introduced by both the horizontal shear force and the vertical pressure are serious and need strictly control,that both the vertical permanent deformation amplitude and the cumulative permanent deformation of the pavement under the same horizontal load decrease with the acceleration of load moving,and that the sensitivity of horizontal moving load to vertical permanent deformation well matches that of the corresponding action time.

Comparison of Speech Intelligibility Between Standard Chinese and English by Native Chinese Listener in Rooms

Peng Jian-xin Lv Yong-xin Liu Xiao-jun Lu Xiao-dong

2011, 39(3): 130-134. doi:10.3969/j.issn.1000-565X.2011.03.025

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Subjective speech intelligibility scores of Chinese and English are obtained through the sucjective evaluation of simulated room acoustical signals with different objective speech intelligibility parameters by a native standard Chinese listener.Then,the relationships and their difference between the scores and the speech transmission index STI for Chinese and English are analyzed.The results show that Chinese and English speech intelligibility scores increase with STI,that Chinese speech intelligibility scores are higher than English ones for the rhyme test words under the same conditions with native standard Chinese listener,and that the same circumstance occurs at high STI but opposite result is obtained at low STI for HINT sentences.

Effect of Via Microstructure on Cu/low-k Stress-Induced Voiding

Lin Xiao-ling Hou Tong-xian Zhang Xiao-wen Yao Ruo-he

2011, 39(3): 135-139. doi:10.3969/j.issn.1000-565X.2011.03.026

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Based on the kinematic hardening model of copper,the Cu stress in different Cu/low-k via microstructures are modeled and analyzed via the finite element method to explore the changes of via height,via gouging depth and barrier layer thickness at the via bottom due to the process variation of interconnected via and via barrier layer.Then,the corresponding interconnected via and bottom interconnection stress-induced voiding（SIV） varying with the changes are analyzed.The results indicate that the via microstructure effect of Cu/low-k interconnection is a dominated factor affecting the interconnection stress and the SIV,that the via with high aspect ratio is more susceptible to SIV due to height variation,that the via gouging with suitable depth effectively improves the reliability of stress migration,and that the interconnection SIV performance and the thickness of barrier layer at the via bottom should be compromised because there exists contradiction between the two factors.

Double-Side Radiating Leaky-Wave Antenna Based on Composite Right/Left-Handed Coplanar Waveguide

Liu Chuan-yun Chu Qing-xin Huang Jian-quan

2011, 39(3): 140-144. doi:10.3969/j.issn.1000-565X.2011.03.027

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Proposed in this paper is a double-side radiating leaky-wave antenna based on composite right/left-handed（CRLH） coplanar waveguide（CPW）.By analyzing the dispersion diagram of the antenna unit,a balanced property is confirmed.The designed antenna can implement backfire radiation due to the left-handed property of the CRLH structure,and,in balanced cases,the gap between left-handed and right-handed regions can be su-ppressed.Consequently,a traveling wave along the structure occurs and the antenna implements transverse radiation at the balance point with non-zero group velocity.Measured results show that the proposed antenna can offer continuous radiation almost covering backfire-to-endfire directions.

“From Shore to Shore it is Wide at High Tide,and Before Fair Wind a Sail is Lifting”:Review and Prospect of Journal of South China University of Technology ( Natural Science Edition) to the 50th Anniversary

Liu Shu-hua Fu Xiao-qin Niu Xiao-guang

2011, 39(3): 145-149. doi:10.3969/j.issn.1000-565X.2011.03.028

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In this paper,the background of start publication of Journal of South China University of Technology ( Natural Science Edition) is introduced,and the development history of the journal,including such four stages as the initial establishment stage,the adjustment stage,the normalization stage and the fast development stage,is reviewed. Afterwards,by summarizing the ideas and experiences of publication during the past 50 years,the authors point out that a further development direction of the journal should be explored in the aspects of thinking innovation,team construction,internal management improvement,internationalization-degree promotion and digital-publication practice participation.

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