The Stability of SiO₂ Sol
QIU Chun-yang,ZHANG Ke-zheng
2005, 25 (2): 1-4.
Abstract ( ) PDF ( 274KB ) ( ) 　　
　The SiO₂ sol is a kind of colloid solution , with SiO₂ particle dispersing in water or organic solvents , and has been widely used in the industries of the ceramics, textile , papermaking , paint, water treatment and semiconductor and so on .SiO₂ sol was prepared from tetraethoxysilane(TEOS)by sol-gel method with ethanol as solvent and hydrochloric acid as catalyst .The effects of the solvent , the pH value , and additives o n the stability of SiO₂ sol were studied during the so l-gel processing .The effects of these factors can be used to control the stability of the SiO₂ sol .The results show the more the amount of EtOH , the mo re the stability of sol.In the absence o f additives , the stability of sol increases as the pH value is increased.As the pH value is increased , the stability of sol firstly increases, but then decreases when additives are added to the SiO₂ sol.Gelation time becomes long when DMF additive is added to the SiO₂ sol .If the mole ratio of TEABr and TEOS is mo re than 0 .05, TEABr makes g elation time become longer .
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Development of Asphalt for Flame Retardancy
GUO Jin -cun,LIAO Ke -jian,et al
2005, 25 (2): 5-8.
Abstract ( ) PDF ( 261KB ) ( ) 　　
　Asphalt for flame retardancy was investigated by adding flame retardant to Liaohe 70^# high -quality paving asphalt . The performance of flame retardancy and synergism of DBPDO, Sb₂O₃ , ZnBO₃ and Mg(OH)₂ were examined by using the method of oxygen index and comburent flame level.The performance of smoke inhibiting on asphalt between Al(OH)₃ and complexing smoke inhibitor was also studied .The results show that DBPDO, Sb₂O₃ , ZnBO₃ and Mg(OH)₂ exhibit some positive effect on asphalt flame retardancy .The flame retardancy effect of DBPDO is superior to Sb₂O₃ , ZnBO₃ and Mg(OH)₂.But it has greater smoke generation to the others .There is good synergism flame retardancy between Sb₂O₃ and DBPDO.Al(OH)₃ and complex smoke inhibitors act as not only good flame retardant , but also good smoke inhibitor .The effect of flame retardancy and smoke inhibiting are best w hen they were added to asphalt according to certain proportion.Oxygen index of asphalt for flame retardancy reaches 36 .5 % and comburent flame level is the first grade .The amount of smoke generation is lower .
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Prepration of Emulsified Polishing Wax fo r Leather Goods
CHEN Ping,QUAN Cheng -guang
2005, 25 (2): 9-12.
Abstract ( ) PDF ( 263KB ) ( ) 　　
　The artificial beeswax was prepared from paraffin wax and microcrystalline by chemical modification .I ts quality and function is similar to that of natural beeswax .By using artificial beeswax as starting material and water as diluting agent , polishing wax for leather gooes was prepared .The product' s feature is well -distributed sheet , well function and low cost.The effects on stability of emulsifying w ax such as emulsifier type , quantity , stirring speed , emulsifying time and emulsifying temperature were discussed .The results show that the mixed emulsifier comprises two kinds of no nionic surfactants and auxiliary additives .The sphere particle of emulsion is well distributed and very stable w hen the mass ratio of emulsifiers and oil phase exceed 0 .30.Microemulsion is formed w hen the mass ratio of emulsifiers and oil phase exceed 0 .40.The best emulsifying process conditions are :emulsifying time is 10 ～ 30 minutes, stir ring speed is 700 ～ 1 400 r/ min and emulsifying temperature is 85 ～ 95 ℃.The emulsified wax obtained as above has better stability .
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Process of Walnut Oil by Microwave Ex traction
SHAO Hai,LI Li -hua,et al
2005, 25 (2): 13-16.
Abstract ( ) PDF ( 272KB ) ( ) 　　
        The conditions of microwave extracting walnut oil w ere discussed by using the Mars5 microwave ex traction system ,including solvent, microwave extraction temperature , extraction time and the volume of ex traction solvent .According to the results of single fraction experiments, the optimized conditions of microwave extracting walnut oil w ere obtained by orthogonal experiments: extraction temperature is 60 ℃ , extraction time is 12 minutes, 7 m L the liquid volume per gram walnut .Compared with Soxhlet method and magnetic stir ring ex traction method , the results show that the time is shorten obviously(1/ 12 of the time of magnetic mix round extraction, 1/ 20 of time of Soxhlet method), the extracting temperature is 5 ℃ low er than that of conventional method .The consumption of solvent is less than magnetic mix round ex traction and the oil yield is higher than that of conventional method. Composition of fatty acid was analyzed in walnut oil by GC.There are obvious differences of composition of fatty acid between the microwave extraction oil and the conventional ex traction oil.The mass fraction of the unsaturated fatty acid is increased from 82.94 % to 90 .25 %, while the mass fraction of linoleic acid is increased from 43.49 % to 48 .23%.
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Cataly tic Synthesis of tert -Butyl Acetate Wi th Copper(Ⅱ)Bromide
ZHAO Chong -feng,CHENG Yun,et al
2005, 25 (2): 17-19.
Abstract ( ) PDF ( 204KB ) ( ) 　　
        By using copper(Ⅱ) bromide as catalyst , tert -butyl acetate was synthesized via acylation and the product was determined by infrared spectrometry .By using tert -butyl alcohol and acetic anhydride as raw material , the catalytic behavior of copper(Ⅱ)bromide w as discussed in synthesizing tert -butyl acetate .Various factors such as reaction temperature , reaction time , mole fraction of catalyst and molar ratio of anhydride to alcohol , et al, which influence the acy lation reaction , were investig ated in detail.The optimum reaction conditions were given.The results indicate that copper(Ⅱ)bromide exhibit excellent catalytic activity for the acylation reaction of tert -butyl alcohol and acetic anhydride .I t is fairly feasible and has practical value in industry .The optimum reaction conditions are as following :reflux temperature , the molar ratio of anhydride to alcohol is 1.4∶1, reaction time is 2 hours, the mole fraction of copper(Ⅱ)bromide in alcohol is 0 .5 %, the yield of tert -butyl acetate is 83 .46 %.
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Coking in the Process of VGO Ref ining Wi th NMP Solvent Adding Assistant
WANG 　Lei
2005, 25 (2): 20-22.
Abstract ( ) PDF ( 224KB ) ( ) 　　
        The phenomenon of coking often appeared in the process of VGO refining with NMP solvent adding additive .The method of measuring coke content w as founded , and the coke contents of three kinds of systems (NMP+ oil, additive +NMP + oil and additive + NMP + oil + water )were measured respectively under 0 .101 , 0.003 6 and 0 .000 53MPa .There effect of oxygen on the coking of the systems is significant .The effect of oxygen on the coke content of the different systems gives the following subsequence(from great to little):additive +NMP + oil, additive +NMP + oil + water , NMP + oil .The water can resist the coking .The key factor to prevent coking is the operation without oxygen, but it is impossible to be controlled in practice . So the best method is to screen out the suitable additive in oxygen-bearing operation to decrease coke content .
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Synthesis of n -Butyl p -Hydroxybenzoate Under Single -Mode Focused Microwave I rradiation
HOU Jin -song,LI Li -hua,ZHANG Jin -sheng
2005, 25 (2): 23-25.
Abstract ( ) PDF ( 220KB ) ( ) 　　
        Using Discover microwave organic chemistry rigour system , single -mode focused microwave irradiation technology and micro computer control, n -butyl p -hydroxybenzoate was synthesized with sodium bisulfate mono hydrate as catalyst .The reaction was cooled by constringent air at the same time .The effects of the mass of catalyst , the microwave power , time and the ratio of p hydroxy benzonic acid to n -butyl alcohol on the yield were investigated.Under optimal reaction conditions :n(n -butyl alcohol)/ n (p -hydro xybenzonic acid)/ n(sodium bisulfate)is 0 .15∶0 .05∶0.005 8 , irradiation power is 210 W and irradiation time is 28 minutes , the yield of ester is 93 .6 %.The product w as characterized by FT-IR spectrum and melting point determination .Product is consistent with the target product .
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Oxidation Modify Process of Paraf fin Waxes Wi thout Using Catalysts
CAO Zhi -tao,HOU Bo,et al
2005, 25 (2): 26-28.
Abstract ( ) PDF ( 224KB ) ( ) 　　
        The process conditions of oxidation modify of paraffin waxes without using catalysts were investigated.Influences of air flow rate , mass fraction of oxidation initiating agent , reaction temperature and reaction time on the oxidation process and properties of paraffin w axes were studied.The results show that under proper conditions without using catalysts, the oxidized product with better tint, less smell and high acid number are obtained.Reaction temperature and reaction time are important factors, which affect oxidation process of paraffin waxes and proper ties of oxidized paraffin waxes.The optimal oxidation rate would be obtained when reaction temperature is at 150 ～ 155 ℃, optimal reaction time is 6 ～ 8 hours.In the oxidation absence of catalyst , there is no necessary to purify the oxidized product and its quality is stable .Oxidized paraffin waxes obtained from this process can satisfy the formula of many special waxes , especially using them to prepare emulsifying wax , the appearance , viscosity and stability of emulsion is good .
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Synthesis of NdCoO3 Nanopartical by Microw ave -Gel Method
GONG Xiao -jie,LI Li -hua,et al
2005, 25 (2): 29-31.
Abstract ( ) PDF ( 239KB ) ( ) 　　
        The precursors of composite oxides were synthesized by microwave radiation and far infrared radiation heating , in which Co(NO₃)₂·6H₂O and Nd(NO₃)₃·n H₂O were used as starting material, citric acid as complexing agent and NH₃·H₂O as medium . The microwave radioactive heating can accelerate the formation of sol.The precursors were analyzed by TGA -DTA.Black powders were successfully prepared by heating at different temperature in muffle furnace .The structure and crystal size of the powders were characterized by means of physical techniques , including XRD and IR.The XRD chart of sample prepared at 800 ℃ by sol -gel method and the sample prepared by microwave-gel method were compared.The results show that perofskite rare earth compounded oxide NdCoO₃ nano particles are formed in 10 minutes, while it is required 2 hours for the sol -gel method.Microwave heating can accelerate chemical reaction rate , utilization ratio of heat energy is enhanced .
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Isolation Characterization and Diesel Oil Denitrogen of Quinoline -Degrading Bacterium
HONG Xin,YANG Xiang -hua
2005, 25 (2): 32-35.
Abstract ( ) PDF ( 270KB ) ( ) 　　
        Quinoline is poisonous organic compound and not easy to be biodegraded.Nineteen bacterial strains were screened out by enrichment culture to decompose quinoline as sole nitrogen source .By the quinoline-degrading test , HY9 is the best quinoline -degrading bacterium as experimental strain .The curves of deg ration and growth of quinoline -degrading show that the growth ofHY9 strain and degradation of quinoline are concurrent , optimal time is 50～ 70 hours , which is stable stage .Effects of glucose and the volume of initial quinoline on degradation of quinoline were studied.The optimal carbon source is glucose and volume fraction of quinoline is 1 .4 m L/ L.By orthogonal test determination, the optimal conditions are as following :temperature is 35 ℃ , pH is 7.0, time of culture is 4 days, 125 r/ min rotation speed of mechanical shaker .Temperature is the key factor for the growth of cell, then is rotation speed and pH , time o f culture is the unimportance factor .The initial test of denitrification indicates that the denitrification percent for diesel oil is only 13 %.Low denitrogen rate is probably because that the mixing of oil and water is no t perfect , efficient mixing of oil and water is important for the enhancement of denitrogen rate for diesel oil.
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Selective Hydrogenation of FCC Light Gasoline Over Ni -Mo/ Al₂O₃
DAI Dan,WANG Hai -yan,et al
2005, 25 (2): 36-38.
Abstract ( ) PDF ( 278KB ) ( ) 　　
        The bimental Ni-based catalysts supported on Al2O3 were prepared, which were used to the selective hydrogenation of FCC light gasoline .The effect of calcination temperature , content of nickel and molybdenum on the selective hydrogenation performance of catalyst were investigated.The results show that the proper calcination temperature reduces the specific surface area and surface acidity of the catalyst, which increase the stability of the catalyst .Furthermore , molybdenum served as a promoter is in favor of the evenly dispersion of nickel on supporter Al2O3 .Under the following conditions:temperature is 80 ℃, LHSV is 10 h -1 , volume ratio of hydrogen and oil is 10 , pressure is 1 .5MPa , experimenting with the catalyst of Ni -Mo/Al2O3 , the conversion rate of dienes in the FCC gasoline reduce by more than 98 %.The selective hydrogenation catalyst prepared shows excellent activity and selectivity , which can be applied in the field of selective hydrogenation.
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Synthesis of Cyclohexyl Propionate Catalyzed by Iodine
LIU Chun -sheng,ZHANG Xiao -li,et al
2005, 25 (2): 39-41.
Abstract ( ) PDF ( 219KB ) ( ) 　　
        The acylation of cyclohexanol with propionic anhydride was studied by using iodine catalyst .The effects of different factors such as reaction time , the mole ratio of cyclohexanol to propionic anhydride , the mass of catalyst on the yield of cyclohexyl propionate were investigated.The results show that the best of reaction conditions are as following :0.1 mole cyclohexanol , the mole ratio of cyclohexanol to pro pionicanhydride is 1.1∶1 and the mass of catalyst is 0 .08 g ram .After reacting 40 minutes under refluxing , the yield of cyclohexyl propionate reaches 92 .2 %.The product is colorless and transparent .The purity of product is 98.7 %.The reaction was repeated five times.It is shown that the catalyst exhibit a good catalytic activity .The advtanges of the reaction are mild conditions, shorter reaction time and easy manipulation .The product was characterized by refractive index and IR.
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Surface Hardness Af ter Grinding for Hardened Bearing Steel
FENG Bao -fu,MA Chun -rong
2005, 25 (2): 42-45.
Abstract ( ) PDF ( 268KB ) ( ) 　　
　Thermal model based on Jeager' s heat resource theory was established to predict grinding surface temperature .The relations between the tempering hardness and the temperature for hardened bearing steel and low alloy steel were studied.The tempering behavior model of relationship between tempering hardness and temperature was set up.Tempering resulting from grinding heat caused surface hardness changes of hardened steels after grinding .Combining the tempering behavior with the grinding thermal model , the change in surface hardness due to grinding heat could be predicted .Experiments of high speed grinding for GCr15 bearing steel were done .The effects of work speed and grinding depth on surface hardness were researched .The predictive values accord with the experimental results .
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Finite Element Analysis of Quality Factor Influencing Sheet Drawing
ZHU Xiang -zhe,LIN Wei
2005, 25 (2): 46-49.
Abstract ( ) PDF ( 383KB ) ( ) 　　
        In the process of drawing , the sheet often appears crinkling , bloating and ripping .The sheet drawing process includes complex physical phenomena revolved in no n -linearity of geometry , material and boundary .So it is very difficult to be solved by analytic method .Numerical simulation of sheet drawing was made by means of finite element software ANSYS/ LS -DYNA and the position of potential flaw was analyzed.Sheet drawing quality influence that resulted from punching velocity , fiction coefficient and press force w as discussed.The results show that the sheet in the adjacent area of cavity die and punch deforms firstly .The maximal value of stress and strain appears in the outboard sheet o f punch round corners .The maximal bodiness is sheet flange and the maximal attenuation is the sheet of cavity die round corners .The bigger fiction coefficient between punch and sheet is, the bigger the brim stress is.So the wrinkle isn' t easy to emerge in the rim of sheet.The effect of fiction coefficient on parietal stress is complex . Enhancing punch velocity properly can improve computing efficiency and assure computing precision.
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Welding Technology of SA904L S teel Plate
GAO Lei，CHEN Tian -ping，et al
2005, 25 (2): 50-53.
Abstract ( ) PDF ( 296KB ) ( ) 　　
　     A company manufactured an acetic acid removal column reboiler which yielded 4 ×104 t M TPY of differential acrylic fibers for Jilin Qifeng Chemical Fiber Group Co ., Ltd ..The equipment consists of pipe box , shell and pipe bundles.Medium of pipe path is DMAC+AA , which has strong corrodibility .Therefore , the stainless steel plate of 904L is chosen.It is a kind of high alloy steel and has poor weldability .It is easy to generate hot crack, intercrystalline corrosion and stress corrosion crack , especially difficult to control crater crack.According to the generating principle of hot crack , intercrystalline corrosion and stress corrosion crack , this kind of steel' s weldability was analyzed , and a sample of welding techno logy experiment was dissected.Metallogenetic examination and the machine performance test were made.As a result , an appropriate welding specification is found out .
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Pinch Point Theory and Application in the Heat Exchange Network
WANG Li -w en, CHEN Bao -dong,et al
2005, 25 (2): 54-58.
Abstract ( ) PDF ( 378KB ) ( ) 　　
　    At present , there are three main methods in optimum of the heat exchange network :heuristic method , pinch point technology , mathematical programming .In the engineering application, among all methods the pinch point techno logy has been proved to be the mo re efficient and obtain obvious economic benefits.The methods how to solve key problems of pinch point technology and point out the pinch point of the heat exchange network accurately and quickly w ere given , which helped makeeffectively optimum design of heat exchange network and make best use of energy .The solutions to the exceptional cases in the engineering practice were put forward and an example was given.It demonstrated the obvious results of heat transfer after rebuilding .On the basis of analyzing theory foundation and thermodynamic principle , theory limitations of pinch point technology were put forth,corresponding causes explained, and solution methods offered.
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Perfo rmance Comparison Between Helical and Segmental Baff le Board Heat Exchangers and Optimization of Helix Angle
YANG Jun,CHEN Bao -dong,et al
2005, 25 (2): 59-62.
Abstract ( ) PDF ( 270KB ) ( ) 　　
    　Performance test of heat transfer and pressure drop was done in the helical baffle heat exchangers with helix angle of 12°,18°, 30°and 40°.Applying a software Tasc3 o f British Heat Transfer Association, the operation situation of heat exchangers of segmental baffle board was simulated , and the value of heat coefficient and pressure drop was obtained.Through data computation, under the same flow quantity , the overall coefficient per pressure drop of helical baffle board heat exchangers with different helix angles was compared with those of segmental baffle board heat exchangers.Meanwhile , the coefficient at shell side and the pressure drop were studied contrastively for different helix angles of 12°, 18°, 30°and 40°, and helix angle w as optimized .The results show that the overall heat coefficient of helical baffle board heat ex changers in our tests is higher 59.48% than that of segmental baffle board heat ex changers of corresponding structures.Under the test condition, the general performance of baffle heat exchanger with helix angle of 18? is better than baffle heat exchanger with helix angle 12°, 30°and 40°.
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Vacuum Checking of Liquefied Petroleum Accumulator Pot
MA Chun -rong,LIU Ying
2005, 25 (2): 63-64.
Abstract ( ) PDF ( 209KB ) ( ) 　　
        Vacuum checking problems under the different working environments were analyzed in the design process of liquefied petroleum accumulator pot .With computing different media and inner diameters o f pots , a rule whether a liquefied petroleum pot filled with propylene, propane , butane and butylenes could be checked according to vacuum condition in the low temperature w as found .By comparing thickness of inner -press and outside -press barrel w all, it' s concluded that the larger the saturated stream press of liquefied petroleum gas is, the smaller the probability of vacuum check is.On the contrary , the smaller the saturated stream press of liquefied petroleum gas is, the larger the probability of vacuum checking is.Therefore , the conclusion helps reduce the unnecessary checking , increase the designing efficiency , and shorten the product design period .
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Design and Realization of Journal Management System in the Editorial Department
ZHONG Chong -min
2005, 25 (2): 65-68.
Abstract ( ) PDF ( 258KB ) ( ) 　　
        Present situation of journal management in the editorial department in China w as recounted .The necessity establishing journal management system in editorial department was analyzed.Furthermore , the journal management system based on Visual FoxPro6.0 was developed .It consists of six modules, which can realize functions such as thesis' register , inquiry , maintenance ,statistic , backup , print and so on, and help implement comprehensive computerization management for journal editorial.The system improves the management efficiency and level of the editorial department.
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A Blind Image Watermark Algorithm Based on Wavelet Transform
AI Zhi -qiang,JI Yu -bo,et al
2005, 25 (2): 69-73.
Abstract ( ) PDF ( 354KB ) ( ) 　　
        As a new technique applied to protecting the copy right of digital productions, the digital watermark technique has drawn extensive attentions.The watermark technique based on wavelet transform has been an active study field .In order to ensure the concealment and robustness of watermark, a blind image algorithm on the basis of wavelet transform was proposed.Firstly ,watermark was scrambled before the algorithm w as embedded .Then watermark information and spread spectrum sequence are modulated, and combining texture concealable characteristics of human vision system with just differenthating limit, were embedded into DWT domain of carrier image .Finally , making use of autocorrelation function characteristic of spread spectrum sequence ,watermark information was detected .In the detection process, it is not requisite for initial carrier image .The experiment results demonstrate that with the algorithm embedded watermark, watermark is no t easy to be found out .I t has a fine detected watermark effect .The algorithm is robust enough for JPEG degradation compression, clipping , noise attacks and low -pass filtering .
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Design and Implementation of Remote Teaching Sof tw are Based on JMF
ZHAO Xin -hui,LI Wen -chao
2005, 25 (2): 74-77.
Abstract ( ) PDF ( 264KB ) ( ) 　　
　    The technical measures of remote teaching software include articulation , continuity , real -time transmission of audio and video frequency and self -adaptability to the bandwidth .To realize the target , key techniques involve audio and video data acquisition and compression, feedback control of data transfer and transfer rate , data receiving and broadcasting .The characteristics of API of Java Media Framework (JMF)were introduced.The principle and key technique were presented.The implementation method of audio and video data acquisition and compression, feedback control of data transfer and transfer rate , data receiving and broadcasting was given .The software design method based on JMF was described in detail.
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Desig n of SCR Trigger Circui t Based on Intel 80C196KC
WU Yun, 　DAI Wen
2005, 25 (2): 78-82.
Abstract ( ) PDF ( 336KB ) ( ) 　　
　    The design of SCR trigger circuit with Intel 80C196KC single chip microcomputer was introduced, which substituted analog SCR trigger circuit .I t implemented functions of data display and parameter setting , and provided a perquisite for the digitizing of DC motor thyristor control system .Making use of the advantages of Intel 80C196KC, a digital thyristor trigger device o f three -phase bridge SCR circuit was specially designed:the synchronization monitor of the situation of power supply network was adopted. Pulse is output through the high peed output port HSO of 80C196KC to realize digital trig ger device design and achieve reliable pulse trigger .The parameters can beset on -line and displayed on real -time .The system has audible and light alarming function and Menhances man -machine interactive operation.The system possesses advantages such as convenient parameter setting , compactMhardware structure , small volume, a wide range of adjustable speed, w ell stability and reliability of the system , favorable real -timecharacteristics .
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Research and Application of Wireless Application System Based on J2EE
LI Song
2005, 25 (2): 86-88.
Abstract ( ) PDF ( 276KB ) ( ) 　　
        With the development of telecom and network , many large application sy stems have requirements of wireless application.Due to the technology restraint , only simple applications such as short messages, email and so o n are used .Until the prevalence and popularization of J2EE , it can be capable of building more complex wireless application systems .J2EE platform provides not only a applicable model with several layers and module reoccupy , but also a consist security model and a flexible control of affairs .Users can quickly offer creative schemes for markets. J2EE was discussed , and furthermore , combining quickly developed wireless communication equipment, a wireless office system model was brought forward .A wireless mobile query system that is designed according to the model has been put into production and has well performance .It' s prov ed that the model of wireless mobile office information system has good practicality for similar system' s construction .
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Dual Space of Space l→_pq
FU Ying,FAN Chuan -qiang,WANG Jing -xin
2005, 25 (2): 89-91.
Abstract ( ) PDF ( 213KB ) ( ) 　　
        Double sequence space is a kind of important Banach sequence space , but the expression of this kind of spaces' continuous linear functional is not completely clear .l→pq is a sort of double sequence space , in which the expression of continuous linear functional was talked about w hen 0 < p , q ≤1 .Firstly , {eij}∞i , j =1 being Schander basis of space l → pq was proved .Based on the result , the expression of continuous linear functional of the space l → pq was also studied .The dual space of double sequence space l→ pq being (l→pq)＊ =l → ∞∞ was proved
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Proper ties of F Class Generalized Z -Matrices and M -Matrices  
FENG Zhi -xin,LI Yang,SONG Dai -cai
2005, 25 (2): 92-94.
Abstract ( ) PDF ( 205KB ) ( ) 　　
        A new kind of generalized Z - matrices and generalized M - matrices were defined and some properties of the matrices were given .F class generalized M- matrices include not only all M -matrices but also all positive matrices.A matrix A ∈ R^{n ×n} is a Z - matrix if all its non -diagonal elements are non -positive .A ∈ R^{n ×n} is a M- matrix if and only if the A matrix is a Z -matrix and P - matrix .If a square matrix is mean divided and all divided squares are Z - matrices, then it is called F class generalized Z - matrix .If all divided squares are M - matrices , then it is called F class generalized M- matrix .Some proper ties of F class generalized M - matrices were studied too .For example , M , N ∈ R^{n ×n} are the same class of F class generalized M -matrices, under the generalized FAN product , M ＊N is still the class of F class generalized M - matrices.Any F class generalized M- matrix has only one mean division to make it become a F class generalized M -matrix .The results lay a foundation for solving generalized linear complementarity problems
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A Generalized New ton -Like Method fo r Solving Variational Inequalities
TIAN Qiu -ju,SONG Dai -cai
2005, 25 (2): 95-98.
Abstract ( ) PDF ( 250KB ) ( ) 　　
　The variational inequality problem , denoted by VIP(X , F), is to find a vector x ∈ X  ∈ Rⁿ to make F(x)^T(y -x)≥0,y ∈ X ∈Rⁿ .The problem VIP(X, F)can be reformulated as a mixed nonlinear complementarity problem .A generalized Newton-like method for solving variational inequalities was presented .If (ω^＊)is a solution of VIP(X, F), H^＊₀ ={ h(x ^＊), g_i(x ^＊); i ∈ B(x ^＊)} is of full column rank and Q(ω^＊)+H^＊ H^＊T is apositivedefinite matrix .T_i (ω), i =1 , 2, 4 are continuously differentiable , T′_i(ω), i =1 , 2, 4, satisfy Lipschitz' s condition in the neighbourhood N(ω^＊, δ), then the sequences{ω^k}, generated by algorithm , converges Q -quadratically to VIP(X, F)' s solution ω^＊, and prove Q -superlinear convergence without the strict complementarity slackness condition.
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