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Journal of Jilin University Science Edition
ISSN 1671-5489
CN 22-1340/O
主 任:韩啸
编 辑:赵立芹 王健 单凝 李琦
电 话:0431-88499428
E-mail:sejuj@jlu.edu.cn
地 址:长春市南湖大路5372号
    (130012)
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Table of Content
26 July 2008, Volume 46 Issue 04
数学
Existence and Uniqueness of the Solution for the Evolutionary p-Laplacian System with Absorptions
LI Yanbo, LI Huilai
J4. 2008, 46 (04):  579-586. 
Abstract ( 1198 )   PDF (516KB) ( 499 )  
The existence and uniqueness of weak solutions for the Cauchy problem of an evolutionary Laplacian systems were investigated. The exsitence was obtained by virtue of the parabolic regularized method. Owing to the difficulty of the comparison between the two solutions of the system consided, wecombined the enery method with the decay method to reduce our problem to the scalar case, so as to establish the uniqueness of solution.
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Generalized Solution of Singularly Perturbed EllipticEquation Robin Problems
MO Jiaqi,, CHEN Xiu
J4. 2008, 46 (04):  587-590. 
Abstract ( 1156 )   PDF (269KB) ( 434 )  
In this paper, a class of the singularly perturbed Robin boundary value problem for elliptic equation is considered. Under suitable conditions, the existence, uniqueness and asymptotic behavior of the generalized solution for the problems were studied by means of the theory of differential inequalities, obtaining the uniformly valid asymptotic expansion of the solution.
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Estimator of Parameter in a Scale Family under a Symmetric Loss
XU Bao,, WANG Dehui, FU Zhihui,
J4. 2008, 46 (04):  591-594. 
Abstract ( 1372 )   PDF (292KB) ( 420 )  
For scale family c(x,n)θe-T(x)/θ, we dealt with the estimator of parameter θ under qsymmetric entropy loss L(θ,δ)=θqqqq-2(0 Related Articles | Metrics
A General Result on Precise Asymptotics for the Linear Process Generated by Strong Mixing Sequences
LIU Jun, DONG Zhishan,, ZHANG Yong
J4. 2008, 46 (04):  595-600. 
Abstract ( 1270 )   PDF (367KB) ( 333 )  
Using the weak convergence theorem of the linear process generated by strong mixing sequences and the moment inequalities of strong mixing sequences, we otained a general result on precise asymptotics for the partial sums and the maximum of the partial sums of wide range weighted functions and boundary functions. Many important results from the literatures are obtainedeasily as corollaries.
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Upper Bound on Primitive Exponents of a Class of Twocolored Digraph
WANG Rong, SHAO Yanling, GAO Yubin
J4. 2008, 46 (04):  601-606. 
Abstract ( 1307 )   PDF (338KB) ( 338 )  
We studied the primitivity conditions and primitive exponents of a class of twocolored digraphs Dn with three cycles. Firstly we classified the digraphs by coloring. Secondly, we studied the primitivity conditions of all kinds of digraphs. Lastly, we gave the tight upper bound of the exponents of Dn and the characteristicof extremal twocolored digraphs.
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Dynamics Analysis of a Population Biological System with Functional Response and Impulsive Perturbations
HE Decai, HUANG Wentao
J4. 2008, 46 (04):  607-612. 
Abstract ( 1169 )   PDF (359KB) ( 300 )  
A class of nonautonomous mutual interference system with Holling Ⅳ functional response and impulsive harvesting (stocking) is suggested, and sufficient conditions for the extinction and permanence of the system are obtained by using the Floquet theory of impulsive equation and comparison theorem.
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Phaseplane Analysis of JohnsonSegalman Fluid Model with Reaction Diffusion
LI Songtao, ZHANG Xuli, HUANG Mingyou
J4. 2008, 46 (04):  613-617. 
Abstract ( 1192 )   PDF (404KB) ( 270 )  
In this paper, we considered a class of Johnson-Segalman (JS) models involving reaction diffusion. The model is prsented as nonlinear reaction diffusion equations. By virtue of invariant manifolds and study of homoclinic and heteroclinic orbits, we described the structure of phase plane of JS model and gave enlighten global results on homoclinic and heteroclinic bifurcation in a Hamiltonian system with 3wells potential.
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Bending Control of Functionally Gradient Thin Elastic Platewith Piezoelectric Patches Bonded
LIU Wei, DING Lixia
J4. 2008, 46 (04):  618-622. 
Abstract ( 1055 )   PDF (411KB) ( 326 )  
A hybrid rectangular plate comprised of a functionally graded materials substrate with piezoelectric patches perfectly bonded on itstop and bottom surfaces as actuators was investigated. Based on the classical theory of plate, the equilibrium differential equation was deduced for the bending analysis of the thin elastic plate with functionally graded structure on the basis of assuming that functionally graded material properties obey a power law including thickness. The deflection was presented for a simply supported rectangular plate made of functionally graded material bonded piezoelectric patches subjected to electricmechanical loading by means of Navier and Levy’s method. The numerical examples were given and the influences of functionally gradient exponent and applied voltage on the bending deflection were discussed. These results show that gradientexponent has an important effect on the bending deflection and the deflection can be controlled effectively by means of regulating the magnitude and direction of voltage applied on actuators.
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Almost Everywhere Convergences Partial Sum for ρ--Mixing Sequences
TAN Chengliang,, WU Qunying, JIA Zhen
J4. 2008, 46 (04):  623-627. 
Abstract ( 1477 )   PDF (299KB) ( 343 )  
Using a Rosenthal-type inequality for maximum of partial sums for ρ--mixing random variables, we discussed strong conveigence forρ--mixing random sequences. And we extended the classical HintchineKolmogorov convergence theorem, Marcinkiewicz strong law of large numbers, and the three series theorem etc. for independent sequences of random variables to ρ-mixing sequences of random variables without necessarily adding any extra conditions.
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Asymptotic Solution of Initial Value Problems forDifferentialdifference Equation with Small Time Delay
OUYANG Cheng
J4. 2008, 46 (04):  628-632. 
Abstract ( 1592 )   PDF (644KB) ( 345 )  
A class of initial value problems for nonlinear differentialdifference equation with small time delay was studied with the corrective method of boundary layer. Under some definite conditions, the uniformly valid a symptotic solution of the problems was obtained. Especially, two corrective terms of boundary layer were given. They are decreasing continuously and exponentially and have the characteristic of ladder structure.
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Multiplicity of Solutions for Quasilinear EigenvalueDirichlet Problems with p-Laplacian
LI Xiangfeng
J4. 2008, 46 (04):  633-637. 
Abstract ( 1075 )   PDF (361KB) ( 301 )  
Using variational method and a three critical points theorem of Ricceri, we considered a class of quasilinear eigenvalue problemof the formand sufficient conditions which guarantee the existence of at least three weak solutions for the above problem were established. Moreover, the results in the literature are generalized.
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Some Dynamical Properties about Operator Weighted Shift
CUI Puyu, HOU Bingzhe, LIU Juan
J4. 2008, 46 (04):  638-642. 
Abstract ( 977 )   PDF (319KB) ( 260 )  
For an operator weighted shift . Moreover, we show the characteristic of S.
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Central Limit Theorem for Self-normalized Weighted Sumsof φ-Mixing Sequences
LIU Ying, ZHANG Yong, DONG Zhishan,
J4. 2008, 46 (04):  643-648. 
Abstract ( 1207 )   PDF (345KB) ( 334 )  
Let {Xn, n≥1} be a sequence of strictly stationary φ-mixing random variables with EX=0, V2n be an array of real numbers with under general conditions, we obtained the central limit theorem for selfnormalized weighted sum of {Sn/Vn, n≥1}. The results about this scope are improved and extended.
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Optimizing Investment and Consumption within a Real Economic Cycle
LI Wei,, Lv Xianrui
J4. 2008, 46 (04):  649-650. 
Abstract ( 1081 )   PDF (188KB) ( 248 )  
Under the conditions of economic cycle being resulted from the shock of technology and final capital stock being no less than initial capital stock and on the basis of the maximum principles, this paper presents an approach to optimizing the investment and consumption within a real economic cycle.
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Existence and Uniqueness of Solution ofNonlinear Elliptic Systems with Hardy Potential
ZHAO Xin,, CHANG Xiaojun
J4. 2008, 46 (04):  651-652. 
Abstract ( 1479 )   PDF (211KB) ( 293 )  
By means of defining a real bilinear symmetric function and Schauder fixed point theorem, existence and uniqueness for the solution of nonlinear nonresonant elliptic system with hardy potential have been established.
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Existence and Multiplicity of Solutions fora Nonlinear Singular Elliptic Equation
WEI Xiaodan
J4. 2008, 46 (04):  653-654. 
Abstract ( 1121 )   PDF (181KB) ( 273 )  
This paper is devoted to the existence and multiplicity of the solutions of the homogenous Dirichlet problem for a nonlinear singular elliptic equation with natural growth in the gradient. The proofs for the main results are based on a prior estimate of the solutions of approximate problems and compactness techniques.
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Inverse Problem for the Vibrating Beamfrom Its Defective Eigenpair
ZHOU Shuo
J4. 2008, 46 (04):  655-657. 
Abstract ( 1141 )   PDF (203KB) ( 331 )  
In view of the stiffness matrix of the discrete vibrating beam is a real symmetric fivediagonal matrix and the substance of the inverse problem for the vibrating beam is the inverse eigenvalue problem of the real symmetric fivediagonal matrix, a kind of inverse generalized eigenvalue problem is proposed, which is the reconstruction of real symmetric fivediagonal matrix from its defective eigenpair and a principal submatrix. The conditions for the solvability of the problem are given.
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On 3-Choosability of Plane Graphs of Girth No Less Than 4 without 7-,8- and 15-Cycles
WANG Cuiqi, MIAO Zhengke
J4. 2008, 46 (04):  658-660. 
Abstract ( 1151 )   PDF (218KB) ( 257 )  
The choice number of a graph G, denoted by χl(G), is the minimum number k such that if we give lists of k colors to each vertex of G, there is a vertex coloring of G where each vertex receives a color from its own list no matter what the lists are. Now, 3choosability of plane graphs has become a very active research branch, we have used the discharging method to research the subject, and at last we have shown that each plane graph of girth no less than 4 without 7-,8- and 15-cycles is of 3-choosability.
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Existence and Expression of Periodic Solutions ofa Class of Functional Differential Equations
GUO Li,, ZHU Xian ye, SUN Jifang
J4. 2008, 46 (04):  661-664. 
Abstract ( 1425 )   PDF (240KB) ( 272 )  
The present paper deals with the periodic solutions for a class of functional differential equations. Sufficient conditions that guaranteed the existence of periodic solutions for this problem were obtained by the method of pairing exact differential equation. The expressions of periodic solutions were obtained by the fractionalstep method. Furthermore, some examples were presented to illustrate the main result in this paper.
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A Reverse Hilberttype Inequality with Some Parameters
XIE Zitian, MURONG Jumin
J4. 2008, 46 (04):  665-669. 
Abstract ( 1167 )   PDF (266KB) ( 385 )  
By introducing some parameters and the weight coefficient, and using the technic of real analysis, we gave a new reverse Hilberttype double series inequality with two pairs of conjugate exponents, and a best constant factor, and considered the equivalent form and some particular results.
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计算机科学
Protein Structure Comparison by Sort Matrix Alignment
XU Haiyang, ZHOU Chunguang, LANG Meina, ZOU Shuxue
J4. 2008, 46 (04):  670-674. 
Abstract ( 1479 )   PDF (377KB) ( 311 )  
An improved SortMatAlign method was proposed by which MatAlign time complexity was reduced from O(N4) to O(N3) by quick sort and pretreatment of distance matrices. Experiment results support the new method’s feasibility and effectiveness. On the average, the value of RMSD by SortMatAlign is 1.098 times that by MatAlign, and the Svalue comprehensively evaluated by the number of residue pairs and RMSD is 0.968 times that by MatAlign. SortMatAlign is 18.276 times faster than MatAlign to get the same result.
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A Hybrid Algorithm Based on Genetic Algorithmand LevenbergMarquardt
ZHANG Changsheng, OUYANG Dan tong, YUE Na, ZHANG Yonggang
J4. 2008, 46 (04):  675-680. 
Abstract ( 1282 )   PDF (550KB) ( 401 )  
In order to overcome the insufficiencies of premature convergence and weak extensive ability in the combination of Genetic Algorithm and Artificial Neural Networks, we proposed a new hybrid study algorithmGALM, which uses the Genetic Algorithm and Levenberg Marquardt in turn to optimize the neural network. This algorithm mainly includes two stages: First a group of solutions were obtained which approximate the global optimum through cursorily adjusting the genetic algorithm. Then these approximate solutions were taken as the initial values, the GA and LM algorithms were used to optimize the neural networktraining in turn until the satisfactory network parameters were found. Finally we compared the GALM algorithm with other relevant algorithms through experimentation. The results indicate that our algorithm can effectively overcome the problem about falling into the local optimal solutions, and remarkably improves the network learning capability and the convergence rate.
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Research and Improvement of Failure Detector AlgorithmBased on Fresh Point
LUAN Lan, LIU Shufen, ZHANG Xinjia
J4. 2008, 46 (04):  681-686. 
Abstract ( 1299 )   PDF (484KB) ( 270 )  
An improved failure detector algorithm was demonstrated on the basis of fresh point. Using the historical probability of erroneous judgment to change the check time dynamically will increase the accuracy of failure detector in distributed network. A compared experiment of the basic failure detector algorithm, the algorithm on the basis of fresh point and the improved algorithm was conducted, showing that the improved algorithm will increase the accuracy of failure detector gradually in distributed system. 
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Face Pose Estimation Based on Elliptical Model and Neural Network
LIU Miao, GUO Dongwei, MA Jie, SUN Haoxiang, ZHOU Chunguang
J4. 2008, 46 (04):  687-690. 
Abstract ( 1319 )   PDF (497KB) ( 228 )  
The present paper presents a new method based on the elliptical model and artificial neural network for estimating the pose of human face. First, elliptical model is used to fit the boundary of face and the positions of eyes and mouth are located. Second, the BP neural network is trained to learn the relationship between position parameters of eyes and mouth and the parameters of pose. The experimental results demonstrate that this method can estimate accurately pose of faces rotating in a large scope.
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Moving Object Segmentation Based on Symmetrical DifferencingAlgorithm in Video Sequences
XIAO Lijun,, YU Zhezhou, ZHOU Xu, ZHENG Shang, LI Haifeng
J4. 2008, 46 (04):  691-696. 
Abstract ( 1076 )  
This paper presents a new algorithm of moving object segmentation in video sequences, the algorithm integrates the data of moving object that are obtained from symmetrical differencing algorithm and background differencing algorithm, that is, the outline data of the middle frame movement object are obtained by symmetry differencing algorithm and the outline becomes the dividing line, while the exterior is dealt with dynamic background refresh method, and the interior is dealt with background differencing algorithm. The improvedalgorithm solves the hole and hollow when the moving object is short of sufficient surface texture by symmetrical differencing algorithm. The experimental result shows that the algorithm has the advantages of both the two algorithms. The algorithm has simple and accurate physical significance, fast calculation velocity,robust to noise, and can extract the moving body correctly.
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A New Impulse Noise Image Recovering Method
ZHANG Zhen,, MA Siliang, LIU Jianguo, LIU Hui
J4. 2008, 46 (04):  697-703. 
Abstract ( 1255 )   PDF (1268KB) ( 273 )  
In order to denoise impulse noises in images, an adaptive window switching median filtering method is proposed in this paper. First, each pixel is classified as signal or noisy point by the BPnet. Next, the image is filtered by an improved median filter. According to the result of noise detection, the filter can adjust adaptively windows width and sample choicely, each noisy point in image is denoised by filtering. In terms of suppressing impulse noise and preserving image details, the proposed method is better than that based on median filter. Even in the extreme case of 70% noise corruption, noisy images can be effectively recovered.
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Static Analysis Scheme for Mobile Safe Ambients Based on Control Flow
ZHANG Hong, LIU Lei
J4. 2008, 46 (04):  704-710. 
Abstract ( 996 )   PDF (537KB) ( 353 )  
On the basis of the abstract representation of the process of Mobile Safe Ambients, an approximation of the topology of all dynamic processes is computed by exploring the activated movement abilities and communication abilities. Otherwise, the control flow estimate makes no difference among processes which are congruent under α conversion by labeling restricted names and variables with stable names in the syntax of Mobile Safe Ambients. The schema can be exploited to investigate and validate the dynamic behavior and properties of the distributed and mobile systems specified in Mobile Safe Ambients.
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Identity Authentication Scheme Based on Chaotic Theory
JIANG Nan,, YANG Deli, WANG Degao
J4. 2008, 46 (04):  711-715. 
Abstract ( 1069 )   PDF (637KB) ( 266 )  
Based on chaotic theory combined with one time password authentication technology, an identity authentication scheme was presented which can resist attacks in common and resolve ordinary one time password unresisting small number attack and insecurity problems of transmitting plaintext iteration times and easily finding the security leak of collisions in traditional Hash function. In this scheme, traditional Hash function was substituted with chaotic Hash function of more safety about confusion and diffusion, stranger resistant collision ability, and plaintext iteration times was substituted with scramble sort algorithm generated iteration times in network, so it is more safety.
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Design and Implementation of Dynamic Computer Forensics System Based on Network
YU Zhihong, LIU Zhe, ZHAO Kuo, Nuerbuli, SHI Guangkun, HU Liang
J4. 2008, 46 (04):  716-720. 
Abstract ( 1191 )   PDF (636KB) ( 298 )  
In order to solve the problems existed in static forensics technology, this paper presents the design and implementation of a dynamic computer forensics system based on network. Compared with the traditional tools of the system, it performs the work of gathering evidence in advance before criminal action has occurred or in the process of crime so as to avoid the evidence chain lost caused by evidence not scout timely. It can improve the efficiency of the work of gathering evidence; enhance data integrity and timeliness of evidence. This paper describes the architecture, function and work flow, and the implementation of main functions of the core module technology.
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Cell Fixed Position Recognition in Micro Image Auto Analysis
QIU Ju, MA Siliang, ZHANG Zhongbo
J4. 2008, 46 (04):  721-724. 
Abstract ( 1302 )   PDF (481KB) ( 325 )  
This paper presents a method to locate and count the cells based on the computer automatic recognition technique. After enhancing the microcell image, we use circular arc algorithm to locate the cells accurately Then the red cells were distinguished from white cells in the image effectively by using their features, after which we recognized and analyzed those cells quantitiyely. Experimental results show the proposed algorithm can locate and distinguish the cells effectively, and also reduce the wrong diagnosis caused by human being. It enhances the diagnosis efficiency and accuracy.
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A Payloadadapt Intrusion Detection Method
XIAO Wei,, FANG Zhiyi, WANG Wei, YANG Hongjun
J4. 2008, 46 (04):  725-728. 
Abstract ( 1585 )   PDF (390KB) ( 253 )  
According to the network environment constant change and rule classification asymmetry, we developed a high efficient detection method, considering the characteristics of both rules and loads. The method could dynamically generate a rule-matching tree, which adapted the payload features. Then we implemented it over Snort. The experiment results show that using the method, we can not only solve the problem of Network Intrusion System’s high packet loss rates, but also greatly reduce the rule set of each packet or event needs detection. Thus, the detection efficiency will be improved.
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物理
Effect of Complex TiO2 Addition on the Electrical Transport and Magnetoresistance Properties of La2/3(Ca0.65Ba0.35)1/3MnO3
ZHAO Hui, WANG Xiang qun, DU Xiao bo, YU Tao, WANG Dong mei,DONG Yi, ZHANG Yan xiang
J4. 2008, 46 (04):  729-733. 
Abstract ( 989 )  
La2/3(Ca0.65Ba0.35)1/3MnO3 fine powders were synthesied by a Glyine-Nitrate Process (GNP) method. The influences of TiO2 contents on the MR and electrical transport properties (resistivity) of a series of composite samples of La2/3(Ca0.65Ba0.35)1/3MnO3.xTiO2 (x=0,0.02,0.035,0.055,0.09,0.17) were studied. Results show that TiO2 causes the low\|field magnetoresistance, and increases the resistivity.
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Study on Catalytic Purification of Kitchen Fume with Catalysts Supported on Porous Ceramic
GUO Shu li, HAN Wei, JI Hong
J4. 2008, 46 (04):  734-738. 
Abstract ( 1136 )   PDF (743KB) ( 259 )  
The catalyst supported on the porous ceramics was studied for the fume exhaust disposal of cooking fumes. The porous ceramics was prepared from ordinary ceramic powder as raw material with addition of an appropriate amount of pore forming material (sawdust) and the high temperature adhesives (sodium silicate). The main catalytic components contained Cu,Mn,Ni,Ag and Pd. The catalytic performances of the porous ceramics with catalytic components loaded were examined by XRD, SEM and TPR.
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Hard Magnetic Properties of Co80+xZr20-xAlloys
ZHANG Jin bao, XING Bing bing, WANG Wen quan, HOU Peng fei, WU Chun ji, WANG Ming he, BAO Jian, FANG Xiang ming
J4. 2008, 46 (04):  739-742. 
Abstract ( 1630 )   PDF (488KB) ( 301 )  
The structure and magnetic properties of Co80+xZr20-x (x=0,1,2,3,4) alloys and the melt-ribbons were investigated by X-ray diffraction analysis and magnetic measurements. It was found that all the samples exhibited high-saturation magnetization. With increasing annealing temperature, the saturation magnetization values of all the samples increased largely in the experiment. The maximum value of saturation magnetization of melt-spun Co81Zr19 ribbons was 128 (A·m2)/kg, is obtained having been annealed at 750 ℃ for 2 h. For the melt-spun Co82Zr19 ribbons prepared at a velocity of 25 m/s, the maximum coercivity of 60 kA/m has been achieved. Owing to the high content of Co5Zr phase in the ribbons, it can be approximately deduced that the hard magnetic properties are attributed to the existence of Co5Zr phase in the Co-Zr alloys. The coercivity mechanism of the samples is mainly determined by the nucleation of reversed domain.
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Synthesis and Magnetic Properties of Hexagonal Close-packed Ni Nanoparticles
JIAO Zhi wei, LIU Yang, WANG Li li, YANG Jing hai, ZONG Zhan guo, GONG Jie
J4. 2008, 46 (04):  743-746. 
Abstract ( 1327 )   PDF (481KB) ( 258 )  
The hexagonal close-packed Ni nanoparticles were synthesized with the precursor prepared by sol-gel method via heat-treating technique in Ar atmosphere. The synthesis condition, structural and magnetic properties of the samples were analysed by means of thermogravimetric analysis (TG), different thermal analysis (DTA), X-ray diffraction (XRD), transmission electron microscopy (TEM) and vibrating sample magnetometer (VSM). The results indicate that hcp Ni nanoparticles with spheric shape were synthesized by heating precursor at 300 ℃. The average grain size of the hcp Ni particles is evaluated to be about 12 nm via Scherrer equation. The RT magnetic measurement in 800 kA/m field for the samples suggests the unsaturated magnetization in hcp nanoparticles. It turns out that the hcp Ni nanoparticles have unique ferromagnetic with a magnetization of 0.58 (A·m2)/kg and a coercivity of 1.592 kA/m. The critical size of superparamagnetic behavior is near to 12 nm.
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材料科学
Preparation and Magnetic Properties of La0.55Eu0.1Sr0.15Na0.2MnO3
FENG Ming, LI Na, XU Shi chong, LI Hai bo
J4. 2008, 46 (04):  747-750. 
Abstract ( 1337 )   PDF (391KB) ( 237 )  
Perovskite\|type manganites La0.55Eu0.1Sr0.15Na0.2MnO3 were prepared by sol\|gel method. The structure, Curie temperature, magnetocalorie effect, and magnetoresistive effect of the sample were investigated by XRD, VSM, and MPMS. The results show that this material is a single\|phase structure of hexagonal perovskite without other mixed-phases, and the Curie temperature is 310 K. It is found that its magnetoresistance reaches 11.18%, and the maximum magnetic entropy change (ΔSM) reaches a value of 1.45 J/(kg·K) for La0.55Eu0.1Sr0.15Na0.2MnO3.
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Influences of Ultrasonic Vibration and Electric Field on Preparing NaNO2 Nano-particles by Ice Sublimation Method
ZUO Gui hong1,2, LI Dong mei1, MU Jia jia1, CHEN Hai yong1
J4. 2008, 46 (04):  751-754. 
Abstract ( 1179 )   PDF (523KB) ( 267 )  
The small crystallites of quasi sphere aggregates NaNO2 nano-particles prepared by normal ice sublimation method in ethanol were reassembled by ultrasonic vibration to form more stable square aggregates. A 0.5 kV/cm electric field vertically was applied to the sample while the ice was subliming. The results show that the electric field made some NaNO2 crystallites exceed 6 nm in size, and to be discrete. We think it is the electric field to polarize the ferroelectric NaNO2 crystallites. And the polarization of adjoining crystallites in the same direction led to the separated configuration. 
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化学
ynthesis and Crystal Structure of [Ni(phen) 32[Ni(PO4)2(H2PO4)6(OH)6(MoO2)12
LI Xingwei, WANG Xiuli
J4. 2008, 46 (04):  755-760. 
Abstract ( 1566 )   PDF (495KB) ( 269 )  
A new reduced molybdenum phosphate, [Ni(phen) 32[Ni(PO4)2(H2PO4)6(OH)6(MoO2)12](phen: 1,10\|phenanthroline), was synthesized by mild hydrothermal techniques, and the crystal structure was determined by singlecrystal X-ray diffraction analysis. The compound crystallized in the triclinic space groupP1 with a=1.404 2(3) nm,b=1.405 0(3) nm, c=1.408 2(3) nm, α=74.53(3)°, β=74.72(3)°, γ=74.81(3)°, V=2.527 6(9) nm3, Z=1, R1=0.076 2, wR2=0.168 6.
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Synthesis and Recognition of a New Chiral Porphyrin
FA Huanbao, YIN Wei, ZHENG Wenqi, HOU Changjun
J4. 2008, 46 (04):  761-764. 
Abstract ( 1462 )   PDF (410KB) ( 269 )  
An unsymmetric porphyrin was synthesized based on the adjustable property of tetraphenylporphyrin. Then, a chiral porphyrin was synthesized by the esterification between the unsymmetric porhyrin and L-BOCphenylalanine. The chiral recognition of the chiral porphyrin with the L and D-alanine methyl ester showed different chiral recognition abilities for small amino acids. The D-alanine methyl ester was more tightly bound to the chiral porphyrin than its optical antipode.
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Preparation of NaYF4∶Er3+,Yb3+ Upconversion Nanocrystals
SUN Mojie, JIA Ruokun, ZHANG Xiaojun, ZHANG Yushuai, BAI Yubai, REN Hantao
J4. 2008, 46 (04):  765-768. 
Abstract ( 1797 )   PDF (421KB) ( 294 )  
The upconversion nanocrystals NaYF4∶Er3+,Yb3+ were prepared by solgel method. The intense upconversion emission was observed from the nanocrystals under excitation at 980 nm. Xray diffraction analysis suggests that the nanocrystals were cubic. The nanocrystals were found to be welldispersed spherical particles with an average diameter of 70 nm by transmission electron microscopy. The nanocrystals are favorable for the highly sensitive label used in biological detection. The upconversion fluorescence spectrum was recorded on a fluorescence spectrometer. Upconversion mechanism was explored.
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Synthesis, Optical and Electrochemical Properties of Copper Tetra-(2-isopropyl-5-methylphenoxy) Phthalocyanine
HE Wei,, MA Chunyu, CHENG Chuanhui,, YU Shukun,FAN Zhaoqi, XIA Daocheng, DU Xiguang, DU Guotong
J4. 2008, 46 (04):  769-773. 
Abstract ( 1621 )   PDF (521KB) ( 233 )  
Copper tetra-(2-isopropyl-5-methylphenoxy) phthalocyanine was prepared and characterized by MS and elemental analysis. Its photoluminescence (PL) spectra show a peak centered at about 1 180 nm, which indicates that it can be used as a nearinfrared functional material. Electrochemistry shows the redox of this complex is oneelectron processes which include two ringbased reductions and one ringbased oxidation. The identities of these electrode processes were further revealed by performing spectroelectrochemical experiments.
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Kinetics of Curing Reaction of Epoxy Resin/Montmorillonite Nanocomposites
CUI Jiwen,, WANG Shu hong, LI Xiaojun, WU Dongmei, NA Hui, MENG Lingkai
J4. 2008, 46 (04):  774-778. 
Abstract ( 1230 )   PDF (478KB) ( 193 )  
Camontmorillonite was directly modified with hexadecyl trimethyl ammonium bromide. The interlamellar spacing of the organophilic montmorillonite (OMMT), corresponding to the (001) plane peak reached 2.21 nm. The reaction process of the curing system (E51/BADK/MMT) was studied by nonisothermal DSC and carefully analyzed. Based on the Kissinger method, the apparent activation energy (ΔE) was calculated to be 41.03 kJ/mol. The reaction order(n=0.85) was calculated according to Crane theory. The curing reaction conditions with BADK as the curing reagent were found. At last, the thermal properties of epoxy resin/MMT nanocomposites were studied by nonisothermal DSC. The experimental data indicate that Tg’s of nanocomposites are higher.
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生命科学
Isolation and Identification of a Mesophilic Bacteria ZW2531-1Producing a Novel Amylase
WANG Yang, LI Fan, GAO Chaohui,, ZHENG Xiaoyi, ZHANG Yingjiu
J4. 2008, 46 (04):  779-783. 
Abstract ( 937 )   PDF (616KB) ( 209 )  
Twelve amylaseproducing mesophilic strains, newly isolated from Chinese soil were screened according to their ability of starch digestion by clear zone method. Among them, strain ZW2531-1 showed high amylaseproducing ability, and its amylase could catalyze the degradation of starch to produce several oligosccharides including maltose, maltotriose and a large amount of isomaltotriose and isomaltotetraose, without glucose. Strain ZW2531-1 was bacilliform, a spore forming bacterium under an electron microscope. To explorethe phylogenetic position of strain ZW2531-1, its 16S rRNA gene was amplified, sequenced, and then was compared with those of standard bacteria available in Genebank databases. Further, the phylogenetic tree including strain ZW2531-1 was built. All the results regarding strain ZW25311 support that bacterium ZW2531-1 belongs to genus Bacillus, therefore, it could be proposed as Bacillus sp. ZW2531-1.
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环境科学
Affect of SO2-4,HCO-3 and Cl- on Degradation of Mine Water CODCrby UV/TiO2
YAO Enqin, GUI Herong,
J4. 2008, 46 (04):  779-783. 
Abstract ( 877 )   PDF (577KB) ( 215 )  
Effects of SO2-4,HCO-3 and Cl- in mine water on performance of photocatalytic degradation of mine water CODCr with TiO2. After the anions in mine water were fully filtered with anion resin, simulant mine water samples with eath of Na2SO4,NaHCO3and NaCl and composites between the 3 salts were respectively prepared, and photocatalytically degradated CODCr in mine water with homemade TiO2 under ultraviolet light irradiation. When they existed singly, all the three kinds of anions can decline the CODCr photocatalytic degradation rate in the order of HCO-3>SO2-4>Cl-,4.45 mmol/L Cl- accelerating CODCrdegradation rate a little. When composites every two of the three kinds of anions, HCO-3 and SO2-4, HCO-3 and Cl-,as HCO-3 concentration is low, common effects of HCO-3, SO2-4 or Cl- lower CODCr degradation rate, while HCO-3 plays a major role; as HCO-3 is in high concentration, HCO-3 achieves absolute role. In composite experiment of SO2-4 and Cl-,Cl- concentration is 4.45 mmol/L, promoting CODCr degradation rate slightly in the range of concentrations of SO2-4;Cl- is higher than this concentration, Cl- and SO2-4 compositions have the synergy effect on lowering CODCr degradation rate, and are lower than that they exist individually.
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生命科学
Extraction Technology of Schisandra Red Pigment
FAN Rongjun, LIU Pai, REN Tao, LIU Chengbai, CHEN Xia
J4. 2008, 46 (04):  784-788. 
Abstract ( 1312 )   PDF (492KB) ( 277 )  
Schisandra red pigment was extracted with acid ethanol (pH=3) extraction method, by which the effects of three extraction factors including extraction temperature, time and the ratio of material to extraction solvent on the rate of extraction were studied. With the extracting rate of Schisandra red pigment as main indicator, the extracting process was studied by orthogonal test to optimize the acid ethanol (pH=3) extraction method. The optimum extracting procedure of Schisandra red pigment was extracted with ethanol 5fouldvolume of acid as extracting agent for 2 h at 75 ℃. Schisandra red pigment was identified to be indole pigment through FTIR spectra.
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环境科学
Spatial Distribution and Forecast of Nitrogenous Compoundsin Groundwater in Changchun Area
GAO Yanwei, DONG Deming, YIN Hua
J4. 2008, 46 (04):  795-799. 
Abstract ( 1173 )   PDF (564KB) ( 248 )  
Firstly the method of Krige analysis was used to draw up the isograms of spatial distribution according to the statistics of NH+4,NO-2,NO-3 ions in Changchun groundwater in 2006. The densities of the three kinds of nitrogenous compounds changed higher in the northeast and the northwest of the area from the isograms, the density of NO-3 ion was higher clearly from northeast to southwest than the other regions. From the linear form polluted character, it is so pointed out that the main cause was that irrigating the field with polluted water and excessive agriculture chemicals and the pollutant poured into groundwater. The secondly Krige method in a pure time area was used to estimate and appraise the changing trend of nitrogenous compounds, verifying its forecasting function. The result implies the groundwater quality was fairly good in Changchun area, but the density of nitrite moved upward clearly in every area and specially in the area around the city, the consistency of the three kinds of ions changed fairly higher and changing trend would rise, it was connected with human activity and, so it needed to be controlled and prevented.Firstly the method of Krige analysis was used to draw up the isograms of spatial distribution accordingto the statistics of NH+4,NO-2,NO-3 ions in Changchun groundwater in 2006. The densities of the three kinds of nitrogenous compounds changed higher in the northeast and the northwest of the area from the isograms, the density of NO-3 ion was higher clearly from northeast to southwest than the other regions. From the linear form polluted character, it is so pointed out that the main cause was that irrigating the field with polluted water and excessive agriculture chemicals and the pollutant poured into groundwater. The secondly Krige method in a pure time area was used to estimate and appraise the changing trend of nitrogenous compounds, verifying its forecasting function. The result implies the groundwater quality was fairly good in Changchun area, but the density of nitrite moved upward clearly in every area and specially in the area around the city, the consistency of the three kinds of ions changed fairly higher and changing trend would rise, it was connected with human activity and, so it needed to be controlled and prevented.
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