Investigation of Backf lushing Used in Recovering Molecular Sieve Particles by Ceramic Microfiltrat ion Membrane
HUANG Yan -hua,GUO Wen -miao,JIN Shan
2005, 25 (1): 1-4.
Abstract ( ) PDF ( 214KB ) ( ) 　　
        When the ceramic membrane is used to trea t micro -sized inorganic particle suspensions in the microfiltration process, the bigg est problem is that the membrane could be fouled easily .The technique of backflushing is a stable , valid and reusable method to control the membrane fouling in the microfiltration which is demonstrated by a lot of experiments.The investitation was made for the use of backflushing to control membrane fouling in recovering molecular sieve particles by ceramic microfiltration membrane .The influences of backflushing pressure, backflushing time , backflushing interval on the backflushing were studied .The most important factor affecting the recov erflux is backflushing pressure , backflushing time and backflushing interval have slight influence o n reco ver flux .Considering synthetically the influence of pressure proof , energy consume and investment of the equipments , the satisfied backflushing opera tio n parameters are determined:backflushingpressure is 0.4 MPa, backflushing time is 3 second.Based on engineering situation , the effective rate of permeate flux was taken as investigation object of the membrane system .The optimum backflushing interval is determined, which is 10 minutes , w hen the value of the rate of permea te flux arrives a t the maximum .
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Aromatization Products of Condensate
DING Ho ng -sheng,LI Qi -ming,et al
2005, 25 (1): 5-8.
Abstract ( ) PDF ( 358KB ) ( ) 　　
        Aromatization of condensate over ZnNi/ HZSM -5 was investigated and feed stocks, products and tail gas were analyzed accurately by two different gas chromatog raphs.The feed stocks of condensate were analyzed by using (30 m ×0.22 mm i .d.)OV -101 capillary column .The aromatization liquid products were analyzed by using (30 m ×0.25 mm i .d .) PEG -20M capillary column.The tail gases were analyzed by using (30 m ×0 .25 mm i.d .)PLOT capillary column potassium chloride treating .The experimental result indicates that mass fraction of C5 and C6 of the condensate are more than 50%, products of aromatization reach more than 90 % of total aromatics yields and preferable BTX (benzene , toluene and x ylene)selectivity is more than 75%, that the higher the temperature is, the more the tail gases are .Synchro nously the mechanism of condensate aromatization was introduced.The study shows that the aromatization of condensate is an effective approach of utilizing the condensate .
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Synthesis of Cinnamic Acid From Sty rene and Carbon Tetrachloride
REN Li -guo,GAO Wen -yi,ZHAO Chong -feng
2005, 25 (1): 9-12.
Abstract ( ) PDF ( 298KB ) ( ) 　　
     CuCl/γ-Al₂O₃ and CuO/γ-Al₂O₃ catalysts w ere prepared by impregnation method .The 1, 3, 3 , 3 -tetrachloropropyl benzene (I)was sy nthesized from the addition reaction of CCl₄ and styrene in the catalyst system combining CuCl/γ-Al₂O₃ and CuO/γ-Al₂O₃ as well as pyridine.The optimum activation temperatures of CuCl/γ-Al₂O₃ and CuO/γ-Al₂O₃ are 650 ℃ and 750 ℃,respectively.When the mass fraction of CuCl and CuO are 20.0 % and 10 .0%, respectively , the yields of 1, 3 , 3 , 3 -tetrachloropropyl benzene(I)are 62 .8 % and 70 .3 %, respectively .In the acetic acid , the 1, 3 , 3 , 3-te trachloropropyl benzene(I) was hydrolyzed to give cinnamic acid(II)catalyzed with p -CH₃ -C₆H₄SO₃H -H₂SO₄ , FeCl₃·6H₂O, Fe₂(SO₄)₃·7H₂O , ZnCl₂ ,ZnSO₄ , and so on, the yields are 87.0 %, 48.0%, 84 .4%, 77 .4 % and 87.1%, respectively .The purities of 1, 3 , 3 , 3 -tetrachloropropyl benzene(I) and cinnamic acid(I I) are 96.0 %～ 99 .0 %.
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NMP Addi tive Assistant Refining Lubricated Fraction Oil
WANG Gang,WANG Lei,et al
2005, 25 (1): 13-15.
Abstract ( ) PDF ( 298KB ) ( ) 　　
        To improve denitride ratio in lubrication oil NMP refining for improving the stability of basic oil , the me thod of combing physical extraction and chemical reaction was applied , that is , adding additives to the NMP solvent refining process , letting the additiv es reacting with nitride to removing nitride compounds .This additive is appraised synthetically based on the rate of removing basic nitrogen, influence to the properties and yield of refined oil.The sing le stage and the simulating three stages experiments show that the NMP solvent refining with addition of assistant can remove basic nitrogen in distillate oil efficiently and raise the oxidation stability .The mass fraction of assistant has no remarkable effect on the yield of refined oil and its index of refraction.The optimum operation conditions for single stage refining are :solv ent to oil volumic ratio is 1.0, extraction temperature is 80 ℃, the mass fraction of assistant is 0 .7 %.Under these conditions, the yield of refined oil is 87 %, the index of refraction of 60 ℃ is 1.459 8 and the mass fraction of basic nitrogen is 67 μg/ g .The optimum operation conditions for simulating three stages refining are :solvent to oil volumic ratio is 0 .75, the mass fraction of assistant is 0 .5 % , extraction temperature is 80, 70 and 60 ℃ for top stage , middle stage and bottom stage , respectively .Under these conditions , the yield of refined oil is 88 %, the index of refraction o f 60 ℃ is 1.460 1 , andthe mass fraction of refined oil basic nitrogen is 57 μg/g .
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Research of Waste Unsaturated Polyester Resin Split ting Technique
DU Zhao -hui
2005, 25 (1): 16-19.
Abstract ( ) PDF ( 282KB ) ( ) 　　
        The technique to produce fuel oil from unsaturated polyester resin(UPR)wastes was studied by pyrolysis.The process conditions for thermal cracking and catalytic cracking w ere investigated systematically .The experimental results indicate that the temperature for catalytic cracking is 400 ～ 450 ℃ which is about 100 ℃ lower than that for thermal cracking , the yield of liquid phase pro duct increases about 20 %, the reaction time is 70 ～ 80 minutes, and the catalyst -oil mass ratio is 1∶5.Four kinds of catalysts were evaluated as per catalytic property with the results that the yield of liquid phase product is 58 .22%～ 59.14 %with the YB-2 catalyst independently and the best yield of liquid phase pro duct is 68 .76% with both the YB-1 and YB -2.I t is indicated that the best way to reduce the environmental pollution of waste unsaturated polyester resin is by its catalytic cracking .
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T hermal Analysis and Dehydration Kinetics of Zinc(I I)  Methanesulfonate
S U Ting -ting,ZHANG Lian -hui,et al
2005, 25 (1): 20-22.
Abstract ( ) PDF ( 282KB ) ( ) 　　
        The zinc(I I)methanesulfonate was prepared, the dehydration and thermal decomposition of which were characterized in dynamic air atmosphere through TG and DSC analysis.The results show that it co ntains four molecules of cry stallization water and dehydration in two steps (30 ～ 88 ℃ and 88 ～ 170 ℃).The main decomposition o ccurred between 330 ℃ and 480 ℃ after dehydration .The intermediate of tetrahydratezinc methanesulfonate decomposition was identified by X-ray diffraction.It is shown that the intermediate is Zn3O(SO4)2 at 500 ℃.Zinc(I I)methanesulfonate decomposed to ZnO directly at 810 ℃.Dehydration of tetrahydrate zinc methanesulfonate in different heating rates (5 , 10 , 15, 20 ℃/ min)were studied and dehydration kinetics w as discussed by no niso-temperature method .The activation energy E w as calculated by several isoconversional method and nearly equal value was obtained.Additionally, reaction order n and pre-exponential factor A were evaluated .The equations of reaction rate of two steps dehydration w ere confirmed , respectively .
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Isolation and Characterization for Diesel Oil Desulfurization Bacterium Rhodococcus sp .
LIN Jun -zhang,YANG Xiang -hua，et al
2005, 25 (1): 23-26.
Abstract ( ) PDF ( 284KB ) ( ) 　　
        Sulfur dioxide released into the atmosphere during combustion of fossil fuels is a serious environmental problem . Biodesulfurization using microbial is an effective way to compensate o r can even replace the conventional   hydrodesulfurization (HDS) method.Forty - seven strain bacteriums were isolated and pured from soil, from which seven strain bacteriums with obvious desulfurization were re -isola ted.And at last the strain bacterium , named as ZY-75 , which can degrade DBT , w as isolated from the 47 ones and identified as Rhodococcussp.I ts optimal fermentation conditions through the orthogonal experiments are : temperature 30 ℃, mass concentration of sulfide DBT is 94.0 mg/ L, mass concentration of nitride NH4NO3 is 2 .0 g/ L , mass concentration of carbide glycerin is 5 g/ L , incubating time is 4 days and pH is 7 .0 .Under the above conditions, it' s DBT degradable rate reaches 68 %.Furthermore the remove rate for heavy FCC and FCC diesel oil from Fushun No .2 Refinery is tested , and the removal rates reach 24.50 % and 31.19 % , respectively .
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Fin Ef ficiency of Round Fin Heat Conduction
LIU Zhi -wei
2005, 25 (1): 27-29.
Abstract ( ) PDF ( 289KB ) ( ) 　　
        A finned tube is the key component of a finned tube heat exchanger , and the fin efficiency is one of the main parameters in designing a finned tube heat exchanger , and it also has certain applicable value in the comparison o f heat exchange surface.Since the analytic solution of fin efficiency is quite complicated or it is difficult to be computed that an approximate value could basically meet the requirement of a normal engineering calculation , the simplified feasible numerical method is applied for that .Basing on heat balance the mathematical model of heat conduction of the round fin was established with the change of the model to diagonal triangle matrix by finite-difference method.The temperature distribution, heat release rate and fin efficiency are figured out with a computer .From the actual ex ample , the heat release rate θ₁ is 22.92 W, w hen the fin surface temperature is the same with the base tube , the heat release rateθ₂ is 36 .82 W, and the fin efficiency η is 0.62.This calculation could be applied to round fins of different structure sizes,
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Determination of Three Kinds of Trace Elements in the Milk Powder by MPT -AES
ZHANG Dan,LI Li -hua,ZHANG Jin -sheng，et al
2005, 25 (1): 30-32.
Abstract ( ) PDF ( 244KB ) ( ) 　　
        The determination of calcium , iron and zinc in the milk powder by microwave plasma torch atomic emission spectrometry (MPT-AES)with the standard curve method w as studied by using microwave plasma torch(MPT)as ex citation light source, argon as support gas of pasma and sample solution being introduced into a pneumatic atomizer system .The effect of experimental co nditions including hydrochloric acid concentration in the sample solution, nitric acid concentration in the sampl solution, microw ave forward power , carrier g as flow rate, support gas flow rate on determination w ere optimized.The effect of co -ionized elements of sodium and magnesium on the emission intensity of calcium , iron and zinc w as investiga ted in detail .The detection limits of mass concentration for calcium , iron and zinc are 0.92 , 13.82 and 16 .27 μg/ L, respectively .The relative standard deviations (n =6)are less than 1 .79%. The linear rang es are 0.02 ～ 6, 0 .1 ～ 100, 0.1～ 20 mg/ L for calcium , iron and zinc , respectively .The results show that the proposed method is effective for the determination of the quality of calcium , iron and zinc in the milk powder in its accuracy , easy operation,high automation , low operation cost and rapidity .
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Desulfurization of Diesel by Hy droperoxide Organic Acid Oxidation System
YUAN Qiu -ju,ZHAO De -zhi,et al
2005, 25 (1): 33-35.
Abstract ( ) PDF ( 220KB ) ( ) 　　
        The combination process of oxidization and ex traction separation w as carried out for investigating the desulfurization of Liaohe straight run diesel.Peroxy acid prepared with hydrogen peroxide and formic acid w as used as oxidation reagent, which sulfur -containing compounds in diesel can be converted to the corresponding sulfates having strong polarity .According to the rule that the like dissolves each other , DMF w as an effective solvent for extracting such sulfates from diesel, so were the sulfur compounds removed .The operating parameters w ere studied, such as reaction time, the oxidation temperature, volumic ratio of oxidant to oil and ultrasonic energy .And the suitable operating conditions of the labor a torial experiment are :reaction time is 60 minutes;reaction temperature is 70 ℃;volumic ratio of oxidant to oil is 1∶10;use o f ultrasonic energy , under which the desulfurization rate is 67 .5 % which meets the state , s requirements for sulfur contents in diesel.
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Isolation of a Stain of Deg rading Chlorobenzene and Its Deg rading Condi tions
ZHANG Jing,WANG Zhan -yong,SU Ting -ting
2005, 25 (1): 36-39.
Abstract ( ) PDF ( 273KB ) ( ) 　　
        In order to have the strain capable of degrading chlorobenzene , a strain LP01 was isolated from Fushun No .2 refinery' s sew age disposal factory activated sludge .The stain is identified as Pseudomonas sp.by the appraisement of colonies character , thallus morphology , staining and recessive reaction .The factors influencing the strain' s chlorobenzene degrading ability , such as cultivatable temperature, substrate mass concentration , pH , and shaking table revolution were studied .The optimum conditions for degrading chlorobenze were chosen by orthogonal experiments.The results show that the optimum conditions are as follows:temperature is 35℃, mass concentration of substrate is 30 mg/ L, pH is 8, shaking table revolution is 120 r/min , under which the biodegrading rate reaches to 93.9%.
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Separation of Catalyt ic Cracking Slurry Oil With Furfural and Application
WANG Feng,ZHAO De -zhi,et al
2005, 25 (1): 40-44.
Abstract ( ) PDF ( 321KB ) ( ) 　　
        In order to increase the processing quantity of the catalytic cracking unit and the recovery of its light oil , it is necessary to discharge the slurry oil largely .This makes part of alkane and aromatics, which are the ideal components for the refinery , into the slurry oil causing the FCC feedstock loss.At present , the discharged slurry oil is partly used as the blending component for other units besides as the fuel oil , so , it is under utilized .To lift the reasonable utilization of it , furfural ex traction w as used to separate the slurry oil, this method can effectively separate the cracking part and the faction containing mass aromatics in slurry .The results show :the cracking par t of the slurry can be used as catalytic cracking feedstock or hydrocracking feedstock ;the faction containing mass aromatics can be applied to produce such chemicals as plasticizing agent , softening agent , asphalt , and so on.I ts application is an optimistic one .
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Cerous(Ⅲ)Chloride Heptahydrate Catalyzed Synthesis tert -Butyl Acetate
GUO Chun -yan,HUANG Zhan -kai,et al
2005, 25 (1): 49-51.
Abstract ( ) PDF ( 210KB ) ( ) 　　
        On account of the steric hindrance effect of tert -butyl alcohol, tert-butyl acetate is usually synthesized via acylation and its catalyst is requested strictly .Tert -butyl acetate was afforded from tert -butyl alcohol and   acetic anhydride in the presence of cerous chloride and the catalytic activity of the catalyst was studied.Some factors, which would influence the yield of the product , such as reaction time , reaction temperature, catalyst dosage and the optimum mole ratio of reactants and so on , were discussed .The results show that cerous chlo ride has a better catalytic activity for the acylation of tert -butyl alcohol and acetic anhydride .The study on optimization of reaction conditions indicates that the optimal conditions of the acylation are as following the mole ratio of acetic anhy dride to tert -butyl alcohol to cerous chloride is 1 .5∶1∶0.004; reflux time is 120 minutes ;and the yield of tert -butyl acetate is 82 .60 %.Refractive index and infrared spectrometry show that the product is pure .
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Effect of Car rier Activation on Etherif ication Activity of PW₁₂/Carbonized Resin Catalyst
WEI Min,WANG Hai -yan,MA Jun,BAI Ying -zhi
2005, 25 (1): 52-54.
Abstract ( ) PDF ( 212KB ) ( ) 　　
        The carbonized resin w as prepared using strong acid cation exchange resin as the precursor .Using the carbonized resin as carrier , the carbonized resin supported PW₁₂ catalyst was prepared by loading PW₁₂ on the carbonized resin .Effect of activation condition of the carbonized resin on the surface performance, loadings of PW₁₂and stability of PW₁₂ were investigated.The adsorption process of solid acid catalyst PW₁₂ on carbonized resin w as influenced.Research results show that activation of HNO₃ is better than that of HCl, H₂SO₄ and H₃PO₄ , and the optimal concentration of HNO₃ of the pretreatment solution is 4.5mol/L .The etherification of light catalytic cracking gasoline and methanol w as carried out under the conditions of reaction temperature is 70 ℃,methanol and olefin mole ratio is 1.1, pressure is 1 .0 MPa , LHSV is 1.0 h-1 .The conversion of tertiary carbonic olefin is up to 56.68 %, which is higher than that of D005 strong acid cation exchange resin catalyst.
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Determination of Trace Elements in Agar#br# ———Noncomplete Digestion -Flame Atomic Absorption Spectrometry
LIU Li-xing,LIU Li -jun
2005, 25 (1): 55-57.
Abstract ( ) PDF ( 217KB ) ( ) 　　
        The noncomplete digestion method was applied to the treatment of agar sample , i .e .the sample was     digested in concentrated nitric acid, and then the product of the digested sample was dissolved in emulsifier Triton X -100 obtaining the homog eneous and transparent solution of the sample .Thus the no ncomplete digestion -FAAS method for determination of calcium , magnesium , iron and zinc in agar was established .La3 + w as used as releasing agents for calcium and magnesium to eliminate the interference by co -existing elements in the sample.The results show that the viscosity of test solution is identical to its blank solution .The pretreatment conditions of sample , background absorption interference, the detection limit and characteristic concentration were investigated.The linear ranges of mass concentration are 0 ～ 14 mg/ L for calcium , 0～ 0 .8 mg/ L for magnesium , 0 ～ 7 mg/ L for iron and 0 ～ 1.0 mg/L for zinc .The relative standard deviations of determination are less than 2.2%.The determination results by this method are consistent with those obtained by ashing method.The relative errors are less than ±2 .3 %.I t is concluded that for FAAS determinations , the displacement of ashing method by noncomplete digestion method for the sample pretreatment of agar is possible .
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Performance of Colored Paving Asphalts
GAO Ming1, XIAO Bin,et al
2005, 25 (1): 58-60.
Abstract ( ) PDF ( 280KB ) ( ) 　　
        Under certain process conditions , four brands colored paving asphalt conforming to GB/ T15180-94 standard w ere prepared by blending Liaohe asphalt and a variety of additives , blender and pigment .The road performance of 70^# and 90 ^# colour paving asphalt was evaluated and their aging resistance was studied by viscosity method .The results show that these two brands colored asphalts whose penetration index ranged from -1.2 to +1 .0 have the characteristics of good temperature susceptibility , their equivalent softening point (T₈₀₀), equivalent brittle point(T₁₂)and viscoelastic space(T₈₀₀ -T₁₂)are similar or better than those of the cor responding standard of asphalt , they exhibit high temperature stability , good low -temperature cracking resistance , and the 70^# colored paving asphalt with lower aging index than 90 ^# has better aging resistance.
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A Kind of Curved Surface Helical Baf fle Heat Exchanger With Special Form
CHEN Shi -xing,ZHANG Zhen -hua
2005, 25 (1): 61-63.
Abstract ( ) PDF ( 246KB ) ( ) 　　
         The basic features of the curved surface helical baffle heat exchanger with special form of baffles was introduced .In the exchanger the fan-shaped baffles fixed with banking angle  α   and backward tilting angle β  are connected by lap with triangular baffle boards.The approximate helicoids are formed at the sides of shell.The peripheries of baffles assume successive helices .The backward tilting structure of similar fan -shaped baffles can reduce counter press caused by ordinary helical baffles to the fluid .The binomial action to pitch is realized by the angles of  α and β  and at the same time the resistance to fluid is reduced which is similar to the partial resistance caused by traditional segmented baffle exchangers when the area of baffle board is large .The curved surface helical baffle heat exchanger with the special form of baffles cuts maximally down the resistance to fluid, enhances heat transfer efficiency and heat transfer coefficient , namely the over -all properties of heat transfer of heat exchanger and resistance , at unit pressure drop , and realizes the aim of saving energy and materials .
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Analysis of Mesh Dehiscence of 904L Used in MEK Uni t
ZHANG Yu -guang
2005, 25 (1): 64-66.
Abstract ( ) PDF ( 169KB ) ( ) 　　
        The on -the -spot research and observation of corrosive shape w ere made for mesh dehiscence of water hat screen cloth in 904L under the working conditions of 6 MPa , 155 ℃, pH 37 using H type resin catalyst for producing me thyl-ethyl-ketone .The mesh crack w as found to be belonged to stress corrosion cracking through analyzing and observing alloy agent mass fraction, corrosive media test, inner material impurity , mesh residual stress resource , and crack shape of 904L.And also the expatiating was made for the main reason causing SCC ;lack of Ni, Mo and Cu content in the materials, excess of C and inner material impurities, much residual stress, and the damage to the inactivited surface during transportantion and installation.The process of SCC is that catalyst and mesh surface form the gap , and it is quickly acidificated.When pH falls to activating value of 904L , passivating film is destroyed in the gap because of reducing reaction .The macro corrosive battery is formed among metal inter surface , electrolyte solution and outer surface.When the corrosive depth develops to a certain value , it causes stress concentration resulting in cracking .The crack is vertical to the mesh circle and develops along with the mesh radius.When it reaches to the neutral surface of the mesh, the cracking disappears.There is no crack in the internal pressure area of neutral surface .Therefore , the crack can' t be found in the deeper corrosive pit of mesh surface .
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Application of Computer Information System in Hospital Management
ZHOU Hang,RUI Guang -hai
2005, 25 (1): 67-70.
Abstract ( ) PDF ( 341KB ) ( ) 　　
        The current hospital information system (HIS), especially hospital organization , personnel structure, professional description , information characteristics and communication conditions, was analyzed .The existent problems were put forward.The whole design schemes of system were introduced .The design goals, principles, design constraints and coding principles were summarized .The function design of target system was expounded in detail.The application platform and development environment of database were chosen.The design for network environment of hardware , whole scheme of network environment , and detailed design were described.The key techniques involved in oriented object technique , uniform modeling language , three -layer client/ sever structure were introduced .Development technique of application software based on three -lay er structure was discussed.
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Design of the Dialog Box in User Applicat ion Program Based on AutoCAD
WANG 　Shu
2005, 25 (1): 71-74.
Abstract ( ) PDF ( 279KB ) ( ) 　　
        Design of the dialog box in user application program based on Auto CAD contains mainly interface and driver design of dialog box .Interface design of dialog box focus on meeting the need of searching straight requisite data in user application, inputting conveniently cor responding parameters and selecting pictures .The key of design o f dialog driver is to process user operation , i.e . callback of dialog box .Taking ex ample for interface and driver design of dialog box of two -dimension parametric design of standard parts such as conic roller bearings in the field of machine , a DCL file to define the interface was given .With a user choosing a bearing diameter series in popup list tile, a callback program how to add list elements to list tile was described in details.After the user searched and chose the needed data in list tile , a callback program to display automatically corresponding parameters in edit tile is expounded .
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Design of General Database Access Component Based on COM
JIANG Jun -yin,HOU Li -gang
2005, 25 (1): 75-77.
Abstract ( ) PDF ( 221KB ) ( ) 　　
        COM technique is a prevailing component technology at present .By analyzing the characteristics of COM and database technique, the design and implementation method of general database access component based on COM technique was given. Advanced ADO technology was adopted to connect various kinds of database and accomplish basic database access operation.Utilizing ATL technology as the developing tool of COM , a component of server in -process, i.e .general database access component , was designed and developed , which w as tested and applied by developing application program of client end with Visual C ++ MFC .Various kinds of database , such as Access , SQL Server , etc .were used as background database.Database was accessed through ODBC interface or directly through various kinds of special database engines .The basic operation functions of querying , adding an ddeleting data in database are realized .Also , querying basic information of table in database is achieved .
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Design for an Automatic Generation Algorithm of Examination Schedule in Examination Management
LI Gui -lan,BI Yu -shen
2005, 25 (1): 78-81.
Abstract ( ) PDF ( 264KB ) ( ) 　　
        Examination schedule arrangement is an important and complex job in regular teaching management .There exist lots of constraint conditions and uncertain factors in the arrangement of examination schedule , so it is difficult to automatically generate an effective examination schedule using a program .After investigating diversified kinds of constraint conditions , the examination schedule can be automatically generated by an algorithm design .The software adopted Java' s B/S technology to implement the input of the basic information of the examination dates and time through the operation interface, and manual adjustment for examination schedule created automatically .Since the relationship between the datasheets of examination management is complicated, they will occupy a lot of system resources if datasheets are managed in the server .Thus , the storage process was utilized to implement partial functions.The practical application for mo re than one year in College of Adult Education show s that the algorithm is simple , highly effective and practical .I t is able to accomplish reliably automatic management of the examination job .
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Design and Implementation of Vehicle Monitoring System Based on GPS/GSM and Electronic Map
LIU Shuang,JIA Chuan -ying,e al
2005, 25 (1): 82-85.
Abstract ( ) PDF ( 265KB ) ( ) 　　
        The design principle , system structure and functions, main technical features and its application of a vehicle monitoring system based on electronic map and GPS/GSM were introduced.Global position system (GPS), geographic information system (GIS), global system for mobile communications (GSM), the technique of computer data processing and the technique of data communication were integrated in the system .I t could realize to position satellites day and night , display electronic map , implement real-time vehicle monitoring , play back history records, send monitor and control orders and query information .The system w as able to return immediately signal of vehicle positioning and alarm information , display the run status of mobile vehicle in the form of graphic and data format, send quickly control order , watch several sites with one vehicle moving , return automatically alarm information to the control center , and so on .Experiments show that the system can accomplish intelligent vehicle monitoring , scheduler and management, and satisfy the needs of vehicle position and navigation .
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Realization of Remote Control Sof tware With Dynamic T ransfer Speed
ZHAO Xin -hui
2005, 25 (1): 86-88.
Abstract ( ) PDF ( 277KB ) ( ) 　　
        Using the technology of remote control, The remote computer as conveniently can be controlled as the local one .The technology of remote control can be very useful in the maintenance , monitoring and malfunction diagnosis of remote computers. However , the current software of remote control offers only a fix ed transfer speed .The modes o f linking to Internet are diverse and the link speed is different greatly .Furthermore , link speed of user is possible to vary with line quality and network jam .Thus , the fixed transfer speed limits the use of the software .The software with dynamic transfer speed was implemented through adjusting dynamically compression ratio of the screen images.The principle of remote control software w as introduced .The program design method and outline to realize remote control with dynamic transfer speed by using Java w ere descried in details.Also , the concrete method of implementation was given.
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Analysis of the Price Fluctuation and S tability in Chinese Stock Market
QU Yong -gang
2005, 25 (1): 89-92.
Abstract ( ) PDF ( 277KB ) ( ) 　　
        Stock market is a complicated system on which the different interest members such as the      government, public company ,the stockbroker , stock exchange , the intermediary agency and the investors play a game of ' g o' chess.The traditional basic or technical analysis that focus o n a certain kind of specific aspect , lacks of micro study for stock market .The status and significance of the stock price fluctuation analysis was explained initially .On the basis of the existing models of stock price fluctuation, technical methods of theory analysis and positive analysis of the market ex change data were adopted to study deeply the price fluctuation of Chinese stock market .A system model o f stock market w as established by the use of economic control theory .Taking aggregative index number of Shanghai and Shenzhen's stock ex change as samples , a quantitative analysis of the fluctuation was made .I t has drawn a conclusion that, to the exclusion of interferential factors of policy , Chinese stock market itself is a stable system .
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Multi -Plan Project Selection Method
ZHANG 　Ting -quan
2005, 25 (1): 93-96.
Abstract ( ) PDF ( 258KB ) ( ) 　　
        Since the 1980s , with the development of market economy , Chinese enterprises and their owners face more and more investment choices .In order to maximize economic profits , enterprises must manage their investment projects in a scientific way to reach optimal investment effects.I n reality , an enterprise usually has to make an investment choice from a group of projects, and aims to achieve the optimization o f the group of projects.Therefore , an enterprise must analyze the interrelations between projects, and in the meantime , choose the correct assessment index to make a scientific decision .On the basis of various advantage and disadvantage analysis for conventional assessment methods, a new approach to solving multi -plan project selection by adopting integer planning method is put forth , which is effective in selection of multi -constraint projects , and able to find the optimum plan.It is fit for applications.
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