Table of Content

25 January 2013, Volume 41 Issue 1

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Electronics, Communication & Automation Technology

Design of Notched Ultra-Wideband Antenna with Controllable Stopbandand Corresponding Time Domain Analysis

Chu Qing-xin Yang Guang Mao Chun-xu

2013, 41(1):  1-7.  doi:10.3969/j.issn.1000-565X.2013.01.001

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As the conventional notched antennas realize band-notched characteristic only at a single frequency, amicrostrip-fed notched ultra-wideband (UWB) antenna with controllable notched bandwidths and a high rectangulardegree is proposed and implemented by using open-end slots. The band-notched characteristic is realized by addingtwo L-shaped open-end slots on the U-shaped radiator patch and one U-shaped slit on the feed line of the proposedantenna, and the notched bandwidths are controlled by adjusting the coupling distance between the slots and theslit. With these schemes, the proposed antenna achieves a well-matched broadband impedance in the bandwidthregion of 3.1 ~10.6GHz except the rejection bandwidth region of 5.1 ~ 5.8GHz. The time-domain behaviors of theproposed antenna are then analyzed and the correlation coefficient as well as the pulse-width stretch ratio is calculated.The measured results accord well with the simulated ones, which means that the proposed antenna is suitable forUWB applications.

Follower-Multileader Aggregation Control of Second-OrderMulti-Agent Systems

Liu Xue-liang Xu Bu-gong

2013, 41(1):  8-14.  doi:10.3969/j.issn.1000-565X.2013.01.002

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This paper deals with the follower-multileader set aggregation control of second-order continuous-timemulti-agent systems. In the investigation, it is assumed that the leaders are of the same velocity and cannot receiveinformation from each other, and two new neighbor-based control protocols are proposed to realize the local controlof multi-agent networks respectively without communication constraints and with communication delays. Then, byusing the frequency-domain analysis, the matrix theory and the Nyquist stability criterion, the sufficient conditionsfor the aggregation of all followers in a convex polygon region formed by multiple dynamic leaders are derived underthe two above-mentioned communication conditions. Finally, numerical simulations are carried out to verify theeffectiveness and feasibility of the proposed protocols.

Diving Control of Autonomous Underwater Vehicle Based on AdaptiveBackstepping Method

Jia He-ming Song Wen-long Chen Zi-yin

2013, 41(1):  15-20.  doi:10.3969/j.issn.1000-565X.2013.01.003

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In order to implement precise diving control of the autonomous underwater vehicle (AUV), according tothe kinematic and nonlinear dynamic model of AUV, an adaptive iterative backstepping method based on neuralnetwork is proposed, and a kinematic and dynamic controller is designed. In the investigation, considering theexistence of attack angle and the uncertainties of hydrodynamic damping parameters of the nonlinear model of AUV,a neural network-based controller is designed to on-line estimate the nonlinear hydrodynamic damping terms existingin the pitch motion together with external ocean current disturbances. Then, the adaptive law of the network weightsis presented based on the Lyapunov stability theory to guarantee the uniform ultimate bounding of all signals in theclosed-loop system. Finally, two groups of simulation experiments are carried out to compare the system response ofthe designed controller at a certain control gain and the diving control performance in the presence of disturbances.The results show that the designed controller is of smaller static error and higher tracking precision.

Adaptive Robust Attitude Control of Spacecraft Based on Trajectory Tracking

Zhou Duan Guo Yu Chen Qing-wei Hu Wei-li

2013, 41(1):  21-28,46.  doi:10.3969/j.issn.1000-565X.2013.01.004

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In order to implement the rapid attitude maneuvering control of flexible spacecrafts in large-angle mobi-lity mode in the presence of inertia uncertainties and external disturbances in space, inspired by the model of cellmembrane discharge, an adaptive robust attitude controller is proposed. In the investigation, first, the kinematicsand dynamics of flexible spacecraft are analyzed. Then, an robust control law, which is based on the pre-plannedattitude trajectory and is adaptive to uncertain inertia, is put forward to improve the rapid attitude maneuvering per-formance and suppress the vibration of flexible panels. Finally, to avoid the degradation of pointing accuracy andstability due to the attitude jump during the maneuvering, an improved adaptive robust controller is designed basedon the dynamic model of cell membrane discharge. It is proved that the proposed controller guarantees the asymptoti-cal stability of the closed-loop system. Moreover, under bounded inertia estimation errors, uniformly-ultimatebounded tracking errors can be obtained with the controller. Simulation results verify the effectiveness of the pro-posed controller.

Optimization Design of Sparse Arrays for Phased-Array 3D ImagingSonar Systems

Yuan Long-tao Zhou Fan Chen Yao-wu

2013, 41(1):  29-37.  doi:10.3969/j.issn.1000-565X.2013.01.005

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In order to attain stable and global beam-pattern characteristics of sparse arrays in phased-array 3D ima-ging sonar systems, an optimization method to design sparse arrays in both the far-field and the near-field conditionsis proposed. In this method, first, based on the analyses of the near-field beam pattern, a new energy function isbrought forward for the near-field sparse array optimization in practical engineering applications. Next, the functionis simplified to reduce the computation load. Then, an appropriate near-field sparse array is obtained by minimizingthe simplified energy function via an optimization process. Finally, a second-step optimization of the near-fieldsparse array is carried out to obtain an array with higher sparse ratio for far-field design. The proposed method isemployed to optimize a 100×100 rectangular planar transducer array, and the results are compared with thoseobtained by the existing methods. It is indicated that the proposed method helps to obtain sparse arrays possessingdesired beam-pattern characteristics for both the far-field and the near-field design in random working ranges, withthe sparse ratio being close to those of the existing methods.

Improved YASS Algorithm Based on Virtual Embedding Blocks andOrigin Dithering of Quantizers

2013, 41(1):  38-46.  doi:10.3969/j.issn.1000-565X.2013.01.006

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In order to improve the security of YASS algorithm, a modified high-randomness YASS algorithm namedVHD-YASS is proposed based on the virtual embedding blocks and the origin dithering of quantizers. In this algo-rithm, in order to improve the randomness of the embedding position, a virtual 8×8 H-block, which is used asa substitution of regular 8×8 H-block in the conventional YASS algorithm for message embedding, is created byrandomly selecting an irregular region in each B-block. Then, the shifts of origins of odd/ even QIM (Quantiza-tion Index Modulation) quantizers are controlled by a secrete key to avoid the DCT coefficient clusters due to themessage embedding under the condition of long QIM step. Finally, the proposed algorithm is compared with theconventional YASS algorithm and with two other improved YASS algorithms by experiments. The results show that,at the same embedding rate, the proposed algorithm attains a maximum detectability of 0.614, which is dramaticallyless than the conventional one of 0. 983, and that VHD-YASS is an effective steganography scheme because it is oflarge anti-steganalysis capability, excellent visibility and low complexity.

Fast Belief Propagation Decoding in the Short Length LT Codes

Qi-cong Zhan

2013, 41(1):  47-51.  doi:10.3969/j.issn.1000-565X.2013.01.007

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In wireless transmission, the sudden declination of channel quality would result in the rise of error percentage, when a certain number of coded symbols have been received the input symbols are used to be decoded, which would slow down the decoding speed. Hence, to improve the success probability and speed of partial decoding of short code length LT codes, in this paper, we propose the Fast Belief Propagation (FBP) decoding algorithm, which uses the swap heuristic method and the transformation of the triangular matrix not only to enhance the decoding success proportions but also to reduce the decoding delay. According to analysis and experiment, FBP decoding algorithm is better than the conventional methods, Belief Propagation (BP) and Gaussian Elimination (GE). In the simulation, while the length of the source symbols is 128 bits, the probability of the FBP decoding is 48.09 percent higher than traditional ones at the most and its decoding complexity and time consumption are less than GE.

Representation of Multi-h CPM Signals Through Finite-StateSequential Machine

Zhong Sheng Zhang Jian Yang Chun Wang Peng Liu Lu

2013, 41(1):  52-57,69.  doi:10.3969/j.issn.1000-565X.2013.01.008

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In order to acquire more compact form of PAM (Pulse Amplitude Modulation) decomposition of Multi-hCPM (Continuous Phase Modulation) signals, a novel algorithm to represent Multi-h CPM signals through a finite-state sequential machine (SM) is presented. In this algorithm, based on the periodically varying modulation index,Multi-h CPM signals are represented as the cascade of a periodically time-invariant (PTI) finite-state SM and abank of PTI PAM modulator via the basic waveform decomposition. Then, the state transition process is describedas a reducible and cyclostationary non-homogenous Markov chain by defining even input alphabet ary. The processof state transition with different modulation indexes is validated through some examples, and the model of optimal re-ceiver as well as the simulation results is presented. As compared with the conventional optimal detection algorithmbased on PAM decomposition, the proposed algorithm attains the theoretical detection performance with half numberof trellis.

Automatic Light Adjustment Method for Color CCD Camera Usedin Imaging of High-Temperature Object

Li Zhe-lin Xia Qin-xiang Jiang Li-jun Li Yi-zhen Song A-sheng

2013, 41(1):  58-63.  doi:10.3969/j.issn.1000-565X.2013.01.009

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Due to the whitened or darkened CCD camera images of high-temperature objects with wide temperaturechange range, the object features in the images are weakened. In order to solve this problem, an automatic lightadjustment method based on average gray value for color CCD camera is proposed. In the investigation, first, theeffects of object heat radiation on the image gray during the imaging are discussed. Next, the image features of theobject with the temperature of 8501200℃are analyzed. Then, the relationship between the average gray of RGBprimary color images and the integral time is revealed. Finally, an automatic light adjustment method is constructed,which calculates the temperature zone and optimal integral time by using a prediction image frame, acquires thecolor image according to the optimal integral time, and extracts a proper primary gray image from the color imagebased on temperature zone for further usage. Experimental results show that the proposed method is robust to widetemperature change range and helps to acquire images with stable average gray value of high-temperature objects,which benefits the geometry measurement and surface defect detection of high-temperature objects.

Distributed Compressive Spectrum Sensing Algorithm Based onIterative Support Detection

Li Han-qing Guo Qing Li Qing-zhong

2013, 41(1):  64-69.  doi:10.3969/j.issn.1000-565X.2013.01.010

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In wideband cognitive radio (CR) networks, high sampling rate, wireless fading channels and limitedhardware resources all impact the spectrum sensing. In this paper, a distributed compressive spectrum sensing algo-rithm based on the iterative support detection is proposed, in which CRs spread their detection information in thewhole network through the one-hop communication and the global consensus is achieved on the support set. Then,through a shared support set, the joint sparsity is utilized by CRs during the local sparse signal reconstruction, thusrealizing more accurate spectrum detection. Simulation results show that the proposed algorithm helps to achieveeffective spectrum detection at a sub-Nyquist sampling rate and possesses near-optimal detection performance in theabsence of a fusion center.

Computer Science & Technology

Static File Layout Strategy for Large-Scale Storage System

Long Sai-qin Zhao Yue-long Xie Xiao-ling Chen Wei Zeng Wen-ying

2013, 41(1):  70-76.  doi:10.3969/j.issn.1000-565X.2013.01.011

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Proposed in this paper is a static file layout strategy (SFLS) in improving the access performance oflarge-scale storage systems. In SFLS, first, the disk is divided into two groups that are respectively used to store hotfiles and large files. Then, the files sorted according to the service time are assigned to the two groups of disks inthe ways of Round-robin or Greedy. The disk group that should be accessed is selected according to the size andheat of files, which speeds up the I/ O access of files and improves the access performance of the storage system.Experimental results show that SFLS dynamically adapts to the increase of system scale, costs less response timeand possesses better load balancing performance, as compared with the static layout strategies SP and SOR and withthe dynamic layout strategy HP.

Formal Analysis and Verification of Security for AutomatedTrust Negotiation

Liu Xin-xin Tang Shao-hua

2013, 41(1):  77-82,94.  doi:10.3969/j.issn.1000-565X.2013.01.012

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In order to implement the formal analysis and verification of the security for automated trust negotiation(ATN), this paper takes the formal analysis methods of security protocols as references and proposes a novel ap-proach to ATN modeling and security verification with the help of the process algebra applied π calculus. In this ap-proach, ATN is formalized as the parallel composition of two processes corresponding to two negotiators, and theprocess of a negotiator is the static modeling of its certificates and authorization policies. The ATN security is de-fined as the observational equivalence of the applied π calculus so as to verify not only the security of the authorizationpolicy enforcement but also the privacy of negotiators. With the help of the automatic protocol analyzer ProVerif,the security of ATN is automatically analyzed. Experimental results show that the proposed approach helps to imple-ment automatic security verification with high feasibility and efficiency.

Attribute Reduction Algorithm for Incomplete Decision Table Based onAttribute Discernibility

Ji Xia Li Long-shu Qi Ping

2013, 41(1):  83-88.  doi:10.3969/j.issn.1000-565X.2013.01.013

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Proposed in this paper is a novel attribute reduction algorithm based on the attribute discernibility to re-duce the high computational complexity of the existing attribute reduction algorithms for incomplete decision tables.In the investigation, the external manifestation of condition attribute significance relative to the decision attribute inincomplete decision tables is analyzed, the attribute discernibility is defined, and the calculating method of dynamicupdate of attribute discernibility with the change of reduction subset is proposed. During the attribute reduction, thealgorithm continuously deletes the objects belonging to the positive domain or the consistent blocks having no effecton the positive domain calculation. Thus, the data scale and the time consumption decreases, and the attribute re-duction quickens. Theoretical analyses and simulation experiments demonstrate that the proposed attribute reductionalgorithm for incomplete decision tables is effective and is superior to the existing algorithms in terms of time com-plexity.

Importance Forecast of Customer Requirements Based on ArtificialImmunity and Least Square Support Vector Machine

Huang Ai-hua Pu Hong-bin Li Wei-guang Hou Yue-en

2013, 41(1):  89-94.  doi:10.3969/j.issn.1000-565X.2013.01.014

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In order to improve the dynamic decision level during the quality function deployment and effectivelypredict the importance of customer requirements, a forecast model based on the least square support vector machine(LS-SVM) is constructed. Then, by using the model parameters as the antibody and the importance forecast devia-tion as the antigen, the parameters of LS-SVM model are optimized by means of the clonal selection algorithm. Fi-nally, a numerical printing and die-cutting machinery of corrugated board is used as an example to verify the feasi-bility of the proposed method, and the results are compared with those obtained by the methods based on grey modeland neural network. It is found that the proposed method based on artificial immunity and LS-SVM is feasible andeffective in forecasting the importance of customer requirements.

Chemistry & Chemical Engineering

Effect of Urea on Solution Behaviors and Adsorption Characteristics ofAlkali Lignin

Deng Yong-hong Xiao Liang Feng Xin-jia Yang Dong-jie Qiu Xue-qing

2013, 41(1):  95-99.  doi:10.3969/j.issn.1000-565X.2013.01.015

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In order to investigate the acting force of hydrogen bonds of lignin, the effects of hydrogen bond on thesolution behaviors and adsorption characteristics of alkali lignin solutions were analyzed, with urea as the hydrogenbond-breaking agent. The results indicate that, with the continuous addition of urea, the breaking degree of hydro-gen bond increases and the infrared spectrum of hydroxyl groups moves to the high-wavenumber range, and that asmall dosage urea mainly results in the break of hydrogen bonds between alkali lignin and water, thus decreasingthe particle size as well as the reduced viscosity of the alkali lignin-urea mixture, and increasing the adsorption ca-pacity as well as the surface roughness. However, contrary phenomena are observed at large urea dosage becausethe intramolecular hydrogen bonds may break in this condition.

Adsorption of Dibenzothiophene in Acetonitrile on Fe³⁺ / Cu²⁺ / Ag⁺ -Modified Activated Carbons with High Specific Surface Area

Li Zhong Zhang Hong Xia Qi-bin Zhang Wei Yu Mo-xin

2013, 41(1):  100-104,111.  doi:10.3969/j.issn.1000-565X.2013.01.016

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In this paper, first, activated carbon (AC) with high specific surface area was modified with metal ionsFe³⁺,Cu²⁺ and Ag⁺ through an impregnation process, and three kinds of modified AC, namely, Fe³⁺ / AC, Cu²⁺ / ACand Ag⁺ / AC, were prepared. Next, the products were used to adsorb the dibenzothiophene (DBT) in acetonitrilesolution, and the corresponding isotherms were obtained by means of the static adsorption method. Then, the de-sorption peak areas of DBT desorbed from the AC before and after the modification were measured through tempera-ture-programmed desorption (TPD) experiments. Finally, the total amount of acidic functional groups on the sur-faces of these four kinds of AC was measured via the Boehm titration. The results show that, after the modification,both the total amount of acidic functional groups and the adsorption capacity for DBT increase, that the total amountof acidic functional groups follows the order of Fe³⁺ / AC>Cu²⁺ / AC>Ag⁺ / AC>AC, with the adsorption capacity re-spectively increasing by 30%, 20% and 14%. It is thus concluded that the adsorption capacity of AC absorbents isproportional to the total amount of acidic functional groups, and that the loading of Fe³⁺,Cu²⁺ and Ag⁺ on AC en-hances the adsorption of DBT in acetonitrile solution due to the increase of active sites on AC surfaces for DBT ad-sorption.

Optimization of Process Parameters for Chlorine Dioxide Bleaching ofOxygen-Delignified Bagasse Pulp

Li Jun Xu Gang Xu Jun Mo Li-huan

2013, 41(1):  105-111.  doi:10.3969/j.issn.1000-565X.2013.01.017

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Three-factor quadratic general rotary experiment design was made to optimize three main process parame-ters of the chlorine dioxide bleaching of oxygen-delignified bagasse pulp, namely, the ClO₂ dosage, the NaOH do-sage and the bleaching time. Besides, a quadratic polynomial nonlinear regression model describing the relationshipsbetween the process parameters and the Kappa number, the brightness as well as the absorbable organic halide(AOX) content was constructed. The results show that the constructed regression model passes the significance testand fits well, that the three parameters affect the Kappa number, the brightness and the AOX content in a order of ClO₂ dosage>bleaching time>NaOH dosage, and that, in the optimal conditions, namely a ClO₂ dosage of 0.79%,a NaOH dosage of 0.43% and a bleaching time of 53min, the predicated Kappa number, brightness and AOX con-tent respectively reach 1.83, 73.3% ISO and 10.8 mg/ L, which are close to the experimental values of 1.76,75.0%ISO and 11.3mg/ L.

Preparation and Properties of Anti-Adhering and Acid-ResistantTempered Glass Ink Applied to Automotive

Ren Bi-ye Luo Du-sha Dai Yu-xi Tong Zhen

2013, 41(1):  112-116,132.  doi:10.3969/j.issn.1000-565X.2013.01.018

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A kind of anti-adhering and acid-resistant tempered glass ink applied to automotive was prepared byusing the self-prepared varnish, black tempered pigment (the mixture of glass powders with low melting point andhigh-temperature ceramic melanin) and additives. Then, a synchronous thermal analysis was carried out, and theeffects of sintering temperature and time on the surface crystallization and morphology, the glossiness and the acid-resistance of the ink were analyzed by means of SEM and XRD. Finally, the sintering temperature and time wereoptimized. The results show that the softing point of glass powders with low melting point is 512℃, which is closeto the decomposition temperature of varnish resin of 470℃, so that glass powders can be used as a substitution ofresin for binding because they soften and melt in the sintering temperature range of 600700 ℃. Moreover, it isfound that the crystallization of the black tempered pigment at a relatively low temperature of 579.4 ℃may lowerthe sintering temperature and improve the anti-adhering property of the ink, that the optimal sintering temperatureand time are respectively 660℃and 4min, and that the prepared automotive tempered glass ink is of excellent anti-adhering property, acid resistance and glossiness.

Food Science & Technology

Effect of Ultrasonic Treatment on Aggregation and Stability ofHeparin in Aqueous Solution

Xiao Kai-jun Li Bing-jie Wang Zhao-mei

2013, 41(1):  117-121.  doi:10.3969/j.issn.1000-565X.2013.01.019

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In this paper, dynamic light scattering is employed to investigate the aggregation of heparin in aqueoussolution and to reveal the influence of ultrasonic treatment on the aggregation and stability of heparin. The resultsshow that heparin exists in aqueous solution in the form of aggregated species via multiple-molecule cross-linking,with the particle size of the aggregates increasing with the heparin concentration, that the aggregates cannot be com-pletely eliminated though the addition of sodium chloride leads to a reduction of aggregates diameter in a certain de-gree, and that ultrasonic treatment significantly restrains the heparin aggregation. When ultrasound with 30% ofpower percentage is applied for 3min, the aggregates with the diameter of 1001000 nm change into heparin mono-mers with the diameter of 110 nm, which means that ultrasonic treatment is effective in restraining the heparinaggregation. Moreover, disaggregated heparin powder with the diameter of 110nm can be obtained by the filtrationwith 100nm membrane and subsequent freeze drying. The disaggregated heparin remains stable after the storage formore than 64h at room temperatures.

Thermodynamic Characteristics and Antibacterial Properties of MaltolComplexes with Fe³⁺ and Zn²⁺

Wang Zhong-he Wang Jun Xue Xiao-li Yu Shu-juan

2013, 41(1):  122-126.  doi:10.3969/j.issn.1000-565X.2013.01.020

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Maltol complexes with zinc and iron were synthesized via the hydrothermal method, and the thermody-namic characteristics as well as antibacterial properties of the products were investigated by means of electronicspectroscopy, DSC and pour plate method. The results show that the coordination reaction between maltol andFe(Ⅲ) or Zn(Ⅱ) influences the absorption peak at 320nm and results in a 20-or 45-nm blue shift of the elec-tronic spectrum, which confirm the occurrence of the coordination reaction. DSC results indicate that the two com-plexes both have one narrow exothermic peak with the peak value of 293.9 and 143.9℃, respectively, and that theenthalpy values calculated from the DSC curves are respectively about 122.8 and 374.6 J/ g, which means thatmaltol-Fe is more stable than maltol-Zn. Moreover, the results obtained by pour plate method and optical densitymethod show that maltol-Fe is of more excellent antibacterial property in the order of Micrococcus luteus>Escherichiacoli>Bacillus subtilis >Staphylococcus aureus. The possible antibacterial mechanism of the complexes is also dis-cussed in the end.

Induction Conditions and EMA-qPCR Detection of Staphyloccocus aureusin Viable but Non-Culturable State

Yu Yi-gang Tian Cong Xiao Xing-long Tao Wen-yang Li jin-xia Wu Hui

2013, 41(1):  127-132.  doi:10.3969/j.issn.1000-565X.2013.01.021

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In order to establish a model for the determination of induction conditions of Staphyloccocus aureus in via-ble but non-culturable (VBNC) state and to reveal the effects of temperature, salt concentration and pH value onthe culturable cell number of Staphyloccocus aureus, orthogonal experiments were carried out to optimize the inductionconditions. Then, the culturable cells were monitored and a method based on the DNA-binding dye EMA (EthidiumBromide Monoazide) and the qPCR technology was proposed to detect Staphyloccocus aureus in VBNC state. Theresults show that pH value greatly influences the culturable cell number, and that the cultivation in a nutrient brothmedium with 15% (mass fraction) NaCl and 0.3% (volume fraction) acetic acid at 4℃for 12d is best for theinduction of Staphyloccocus aureus in VBNC state. Moreover, it is indicated that EMA-qPCR is an effective methodto detect Staphyloccocus aureus in VBNC state under different induction conditions, with a Ct value improvement(cycle threshold) varying from 1.29 to 8.56.

Structure of Potato Starches with Different Varieties

Chen Ling Zhao Yue Zhang Pan-feng Li Xiao-xi Li Lin

2013, 41(1):  133-138.  doi:10.3969/j.issn.1000-565X.2013.01.022

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To reveal the structural characteristics of different kinds of potato starches, the semi-crystalline struc-ture, crystalline morphology, amylose content, relative molecular mass and molecular conformation of ten kinds ofpotato starches were systematically analyzed by means of small-angle X-ray scattering, polarizing microscopy, X-raydiffraction and gel permeation chromatography coupled with multi-angle light scattering. The results show that thegranules of the ten kinds of potato starches are of different semi-crystalline structures, for instance, Long 3 posse-sses the minimum semi-crystalline lamellae thickness and the most orderly double-helix alignment, while Qing 2 andQing 6 possess the maximum semi-crystalline lamellae thickness. All the starches are multi-crystal systems withthe same B-type crystalline structure but with different crystallinity and amylose content. Moreover, it is found thatthe weight-average molecular mass of Feiwuruita, Qing 5 and Qing 8 are relatively larger, and that Qing 5 in DMSOexhibits in the form of random coil, while the rest are all in a spherical form. All of the above-mentioned structuredifferences in different scales provide basic data for the development of potato starches for special processing.

Effect of Hydroxyl Radical Induced by Oils on Formation of Diet-Derived N_ε-Carboxymethyllysine

2013, 41(1):  139-144.  doi:10.3969/j.issn.1000-565X.2013.01.023

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N_ε-carboxymethyllysine (CML) is a potential hazard to human health. In this paper, diet-derived CMLwas determined by means of high-performance liquid chromatography-mass spectroscopy (HPLC-MS) in an oil dietmodel system containing lysine, glucose and oil, and the capability of hydroxyl radical (OH·) induced by Fentonreagent for promoting three pathways of CML formation was verified. The results indicate that OH· promotes theCML formation in the model system, and that there are five kinds of vegetable oils that can induce more hydroxylradicals for the transformation of fructoselysine and glyoxal into CML in the order of soybean oil ﹥ corn oil ﹥ oliveoil ﹥ palm oil ﹥ rape oil. Thus, it is concluded that the CML formation in the model system can be promoted bythe hydroxyl radicals induced by oils in Maillard reaction system.