Influence of Different Calculation Methods on Cetane Index Value of Diesel Fuel
MU Ming -ren1,JIANG Xiao -guang，et al
2007, 27 (4): 5-8.
Abstract ( ) PDF ( 156KB ) ( ) 　　
　    The cetane index values of diesel fuel were calculated by the formula calculation and figure calculation method provided by the two standards of GB/ T11139(Distillate fuels -calculation of cetane index)and S H/ T0694 -2000(Calculation of cetane index of middle -distillate fuels by the four -variable equation).The difference of calculated cetane index values with the two methods and the reason for the difference were analyzed .The results indicate that different calculated values could be obtained by the two methods of formula calculation and figure calculation.The values of cetane index would decrease with the increasing of the density at the constant distillate temperature , and increase with the increasing of the distillate temperature at the constant density .In the most situations , the values calculated by formula calculation would be larger than those by figure calculation.
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The Slurry -Bed Hydrocracking Reaction of the Coal -Tar and Lungu Heavy Oil
LI Shu -feng,DENG Wen -an,WEN Ping,QU E Guo -he
2007, 27 (4): 9-12.
Abstract ( ) PDF ( 183KB ) ( ) 　　
　    Co -processing Lungu heavy oil with a kind of coal -tar for preparing high yields purred fuel and high grade paving asphalt was investigated in a rhythmic high-pressure reaction cauldron .The reaction conditions are as follows:mass ratio of coal-tar to heavy oil is 1 ∶3 , temperatures is 430 ℃, reaction time is 60 min, initial pressure of hydrogen is 7.0MPa in room temperature , catalyst content of 200μg/ g .The result shows that the presence of hydro gen and dispersed catalyst would effectively inhabit the coke -forming and gas producing , and increase the yield of middle fractions .According to coking forming , catalytic hydrogenation capability of Ni catalyst is better than that of Fe catalyst, and the oil-soluble catalyst NiNaph offers better catalytic hydrogenation capability than the water -soluble catalyst Ni(NO3)2 .Different starting conditions of compositions will change the distribution of product.In the presence of separation -point 420 ～ 430 ℃, the residue of the reaction can be used as the material for producing 90 # paving bitumen .
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The Preparation and Characterization of Calcium Carbonate Whiskers
YANG Ming -shan,HE Jie,HE Cheng -han
2007, 27 (4): 13-16.
Abstract ( ) PDF ( 553KB ) ( ) 　　
　    The preparation methods of calcium carbonate whiskers we restudied.The factors influencing the growth of calcium carbonate whiskers had been investigated when using magnesium dichlo ride as a crystalline controller .According to or thogonal test, the optimum parameters were obtained , i.e ., the concentration of MgCl₂ is 0 .5mol/ L , the temperature is 90 ℃, the speed of stirring is 250 r/ min and the flux of CO₂ is 1mL/min.The whiskers were characterized by powder X-ray diffraction (XRD) and polarizing micro scope .The characterization results show that the mass fraction of calcium carbonate whiskers prepared is over 97%, with its aspect ratio range between 20 and 30 .
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Preparation and Evaluation of Catalyst for Non -Hydrogen Dewaxing
SONG Yi,LIU Jie, ZAI Yu -chun
2007, 27 (4): 17-20.
Abstract ( ) PDF ( 182KB ) ( ) 　　
　    A new catalyst for non -hydrogen - dewaxing was prepared by hydrothermal method , using ZSM -5 as the principal component and then adding self -made BCM zeolites.Its catalytic performance was evaluated using catalytic cracked diesel fuel and AGO NO .3 as feed stock .The results show that catalyst has obviousde -waxing effect.The pour point can be reduced by 62 ℃, and higher liquor yield(>95%)were obtained at the temperature of 340 ℃ and space velocity of 1 h -1 .The diesel oil produced using the catalyst shows higher cetane number index , lower content of sulfur and nitrogen, and lower pour point , can meet the quality requirements of product blending .
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Synthesis of Benzyl Benzoate Catalyzed by Quaternary Ammonium Salt as Phase Transfer Catalyst
CHEN Shan -shan,SHI Wei -zhen
2007, 27 (4): 21-23.
Abstract ( ) PDF ( 151KB ) ( ) 　　
        The nucleophilic substitution reaction of producing benzy l benzoate by sodium benzoate and benzyl chloride in phase transfer catalysis process was studied .The catalytic performances of sever alquaternary ammonium salts as the phase -transfer catalyst were examined , and found that phase transfer catalyst((C4H 9)4 NI)was the preferred one , the yield of be nzyl benzoate would be up to more than 90 % under the conditions as follows :n(sodium benzoate)/ n(benzy l chloride)=1 .0 ∶1.3, temperature of 110 ℃, reaction time of 2 .5 ～ 3.0 h , moleratio of catalyst and so diumbenzoate 0 .06 and pH value between 5 and 6.
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Synthesis and Characterization of Transitional Metal Complexes of Pyromellitic Acid
WANG Rui
2007, 27 (4): 24-26.
Abstract ( ) PDF ( 207KB ) ( ) 　　
        Transitional metal complexes of pyromellitic acid were synthesized by homogeneous precipitation method , and characterized by TG, element analysis and FTIR.The results of TG and element analysis show their general formula .TG and DTG curves show that the the rmalstability of four anhydrous transitional metal complexes decrease in the order :Zn₂(C₁₀H ₂O₈)>Cd₂ (C₁₀ H₂O₈)>Mn₂(C₁₀ H ₂O₈)>Cu₂ (C₁₀ H ₂O₈).The IR spectrum of prepared complexes suggests that carboxylate groups in the complexes of M(Ⅱ)acted as bidentate chelating with the exception o f the complex of Zn(Ⅱ) as bidentate bridging .
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Kinetics of Synthesis of ETBE Over Mesoporous Molecular Sieve Catalys t SBA -15 -HSO₃
ZHAO Xin, SHEN Jian, JIAO Ho ng -yu
2007, 27 (4): 27-30.
Abstract ( ) PDF ( 236KB ) ( ) 　　
        Well-ordered meso porous organic -inorganic hybrid SBA-15- HSO₃ containing alkyl(methy1)and sulfonic acid groups was directly synthesized via hydro the rmaltechnique and characterized by XRD and nitrogen adsorption.The results show that catalyst SBA -15- HSO₃ , a highly ordered two -dimensional hexagonal me so porous structure , has greater specific surface area , pore size and pore volume .Ethyl tertiary -butyl ether (ETBE)was synthesized by the reaction of ethyl alcohol and tertiary butyl alcohol with SBA -15 -HSO₃ as a catalyst , and the reaction dynamics model had been established.The reaction process carries on in the steel sealed rhythmic reaction cauldron without the influence of internal and external diffusion.The etherification reaction kinetic experiment data could be obtained with the change of the raw material density and the reaction temperature , then such a kinetic model r=kC^1.5_A C^-0.5_B  , would be obtained, finally got the frequency factor 1 .3 ×10⁷ h^-1and activation energy 52.86kJ/mo l.At the same time , a theoretica1 mode1 r=k′C^1.5_A C^-0.5_B  would be obtained according to the reaction mechanism , with frequency factor 1 .2 ×10⁷ h^-1and activation energy 52 .56kJ/mol .So the surface reaction could be considered as the rate -determining step.
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The Magnetic Properties of the Spin -2 Ising Model Under the Transverse Field and Crystal Field
ZHAO Jie,XU Xing -g uang
2007, 27 (4): 31-34.
Abstract ( ) PDF ( 187KB ) ( ) 　　
The mean-field theory was adopted to calculate the high spin-2 transverse Ising model .Theoretical expressions for magnetic moment and free energy were deduced at finite temperature .Magnetization curves of the system at the limited temperature were obtained by the use of numerical calculation .The study emphases on examining the influence of crystal field D and transverse field Ψon magnetization curves of spin systems and free energy .Characteristics of four phase transitions were observed in the magnetization curves :first order -order phase transition, first order -disorder phase transition , second order -disorder phase transition and reentrant phenomenon.The results show that reentrant phenomenon appears only when transverse field is not equal to zero ;first - order phase transition appears in the very narrow range of crystal field and transverse field ;the scope of first order -order phase transition is narrower ;second order - disorder phase transition occurs in the wide range of crystal field and transverse field.In general the temperature of the first - order phase transition is lower than that of the second - order phase transition.Crystal field is a factor to accelerate phase transitions , and transverse field is a factor to limit phase transitions .
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The Corrosion Protection of Hot -Dip Aluminizing on 20^# Steel
CUI Jiao -yue,LI Deng -yue,et al
2007, 27 (4): 35-37.
Abstract ( ) PDF ( 532KB ) ( ) 　　
  　Taking 20^# steel commonly used in heat exchanges as a study object , its anticorrosion of hot -dip aluminizing was researched.As for before and after samples were hot -dip aluminized in acid and alkali corrosion medium , portable apparatus for measuring the instantaneous corrosion rate was used to test the yearly corrosion rate of 20^# steel .The experiment results show that the average yearly corrosion rate of 20^# steel before hot -dip aluminizing is three to six times of that after hot -dip aluminizing .Through the analysis for the mechanism , it has been proved that the heat exchanger will have good corrosion protection after hot -dip aluminizing .
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Iterative Computation of Water and Steam Density Based on the Third Zone of IAPWS -IF97
YAN Yo ng -fei,CHEN Bao -dong,WANG Wei
2007, 27 (4): 38-40.
Abstract ( ) PDF ( 146KB ) ( ) 　　
　    At present , injected gas boilers , with their nominal working pressure approaching critical state , are adopted in the thick oil fields of our country .During the design of injected gas boiler , the character of water and steam under critical state needs calculating .The critical state was assigned to be the third zone in the Industrial standard of IAPWS -IF97 .The computation formula for the character of water and steam of this zone is associated with reduced density , but the solving method of the density is not given by the standard .Based on the formula of IAPWS -IF97, the root equation of density was deduced and the result was got by the chord iterative method .The operating speed of this method is quick , the convergence property is good and the calculated value of the density is close to the value given by the property table .
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The Fuzzy Reliability Optimal Design of the Hydrogenation Reactors
S UN Chun -y i
2007, 27 (4): 41-44.
Abstract ( ) PDF ( 134KB ) ( ) 　　
　    The fuzzy reliability optimal design was applied in the design of hydrogenation reactors.Taking minimizing metal consumption of the reactor hull body as the design objective , the characteristics of normal optimal design can be exerted , and the randomness of design parameters and the fuzziness of design boundary can be taken fully into account .A hydrogenation reactor was designed for the fuzzy reliability optimization.Through comparison of results before and after optimization , the optimal wall thickness is smaller than original design thickness .The optimal weight is reduced by 9 .4 % or so .Optimal results show that such a design is more practical, more reasonable , and more scientific .The design theory also can be applied in the other pressure container design.
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Intensity Analysis of the Excavator Bucket
DENG Zi -lo ng,GAO Cai -lu,FU Yue
2007, 27 (4): 45-47.
Abstract ( ) PDF ( 768KB ) ( ) 　　
　    Taking WY100C hydraulic excavator (bucket capacity for 1 m3)a s a prototype , a physical model of the excavator backhoe working device (bucket)was established by Pro/ E .The finite element intensity analysis of the design model of the bucket was made under the circumstance of dangerous working condition of the largest stress through Pro/ MECH ANICA module .The results indicate that the bucket teeth in the front of the bucket , the roots of the bucket back lug , the hinge areas and the reinforcement areas are the most dangerous parts.Designers should especially take intensity requests of these locations into account.Other parts are relatively safe .The intensity analysis of the excavator backhoe working device (bucket)provides a theoretical basis not only for bucket design , but also for improving the performance of bucket.
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Finite Element Analysis in Pressure Loss of Sprinkler Passage Based on ANSYS / FLOTRAN
LI Ping, QIU Di -fan, ZHAO Ying -jie
2007, 27 (4): 48-50.
Abstract ( ) PDF ( 726KB ) ( ) 　　
　    ANS YS/FLOT RAN is a CFD software based on finite element method.I t is a powerful tool for solving two -dimensional and three -dimensional fluid flow and transmitting heat problems .Computer software ANSYS/ FLOTRAN was used to apply the normal K -εtur bulent model.Installing different types of stabilizers under the different pressures , a numerical analysis was made for simulating the pressure changes inside flow fields of the impact sprinkler .The speed vector graph and pressure isoline map of inner flow fields of rocker sprinklers were obtained .The analysis directly reflects the pressure changes of inner flow fields of rocker sprinkler .Through comparison and analysis , a impact sprinkler with minimum pressure loss under a certain working pressure was designed , which is the impact sprinkler of optimal structure .The theory reference is provided for optimization design of impact sprinkler .
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The Data Collection Based on ARM Embed Chip and TCP/IP Protocol
TENG Guo -ku,ZHANG Yi -go ng
2007, 27 (4): 51-55.
Abstract ( ) PDF ( 175KB ) ( ) 　　
　    To use computer for collecting data and diversion data by A/D exactly , quickly and efficiently becomes an important part of modern industry control production.However , under the current production conditions, there still exists incomplete part if only depending on SCM industry control .So , taking embed chip S3C44B0 as control platform, the modified control system has advantages of higher real-time and better reliability than before .
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Matching Design of an Exact Model for Discrete Hamme rstein Systems
SHEN Qing -bo, DING Yuan -ming
2007, 27 (4): 56-59.
Abstract ( ) PDF ( 249KB ) ( ) 　　
    　A matching design of exact model was presented for the discrete time nonlinear system described by a Hammerstein model .The Hammerstein model consists of a memory -less nonlinear function represented by the odd -order polynomial and a linear time invariant (LTI) subsy stems in cascade connection .The controller structure of the exact model matching was proposed, and self -adaptive control algorithms were deduced for the Hammerstein model .The effectiveness of the pro posed scheme is validated in numerical simulation way .
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Applying Improved Immune Genetic Algorithm in the Optimization Design of Network
XIAO Xia
2007, 27 (4): 60-63.
Abstract ( ) PDF ( 341KB ) ( ) 　　
　    Traditional methods are difficult to solve combinatorial optimization problems of network planning .An improved immune genetic algorithm was adopted to solve for network planning .The diversity of population and global optimization of genetic algorithm are improved greatly .The model took minimum expenses of network architecture as optimal objective , and applying the same medium , node limited load , network radiant connectivity as constraint conditions, then designs network structure by immune planning .The evolution results turn out that in comparison with conventional genetic algorithm , the improved immune genetic algorithm has better self -adaptability and effects.
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Fault Diagnosis of T ennessee -Eastman Process Based on the Improved Wavelet Network
LIU Xiao -qin,SHEN Do ng -ri,SU Cheng -li
2007, 27 (4): 64-67.
Abstract ( ) PDF ( 255KB ) ( ) 　　
　    BP algorithm trends to fall into the local minimum value , slow convergence speed and frequent oscillation.The wave let BP network was used , and self -adaptive learning rate algorithm based on the sign change of gradient and momentum item we re added in it .The improved algorithm was applied in Tennessee -eastman process of a multiple - variable and nonlinear system .The results show that the algorithm can improve the recognition accuracy of fault classification.
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Research on One -Time Password Authentication System
ZHANG Li,BI Yu -shen, HUA NG Lu
2007, 27 (4): 68-70.
Abstract ( ) PDF ( 129KB ) ( ) 　　
　    In the traditional password authentication system , user's passwords a re mostly transmitted through the Internet in the way of plaintext and keep constant, resulting in that attackers can get reusable passwords through wire tapping and invade the system .One -time password system lets users log in using different passwords every time , which can prevent effectively the attack of password reuse and enhance the security of system .The one -time password authentication system of S/key was introduced , and the security vulnerability of system was descrided.A one -time authentication scheme of streng thened SOTP was presented and the security of the new authentication system was analyzed.
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Comparat ive Research on Regional Economy Streng th Based on Factor Analysis
SONG Huan -bin,SUN Hong -peng
2007, 27 (4): 71-74.
Abstract ( ) PDF ( 206KB ) ( ) 　　
        The economy strength of 31 regions in our country in 2000 and in 2005 was analyzed comparatively by selecting an index system of reflecting regional economy strength and using factor analysis method.The analysis results show regional economy strength and the change trend , which provides theoretical base for the regional economy development in future .The results also demonstrate the necessity of developing the We st , revitalizing the Northeast old industrial base , promoting the rise of the middle area and encouraging the East to take the lead in the development .
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Eliminating Systemat ic Errors of the Double -A rm Electric Bridge Through Measuring Resistance in the Way of Exchanging Arms of Bridge
FU Shi -min
2007, 27 (4): 75-76.
Abstract ( ) PDF ( 160KB ) ( ) 　　
　The systematic errors of the double -a rm electric bridge w ere discussed by using the method of exchanging double-bridge arms.The method eliminates not only the influence of the resistancer on measurement results , but also the influence of the systematic errors of the resistance box on measurement results .Accuracy of measurement is greatly improved.
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Relative Analysis on the Senior Management Incentive and the Performance of the Listed Companies
HE Zhi -guo,YU Hui -chuan
2007, 27 (4): 77-80.
Abstract ( ) PDF ( 162KB ) ( ) 　　
    　Using the software spss15.0, a relative analysis was made for the senior management incentive and the performance of listed companies in the petroleum , chemistry and plastics industry in Shanghai stock exchange .The analysis result shows that the performance of company is positively related to the remuneration of the senior management , while it isn't significantly related to the share proportion of the management;the remuneration of the senior management is not obviously related to the share proportion ;the shares proportion of the senior management is negatively related to the shares proportion controlled directly by the state , while the remuneration of the senior management is not significantly related to the share proportion controlled directly by the state .The result also shows the reform of the split share structure has contributed to the establishment and the perfection of the incentive system of listed companies in the petroleum , chemistry and plastics industry .
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Empirical Study on the Technology Spillover Effect of Ethylene Item
GUAN Ming -kun,YAO Nan
2007, 27 (4): 81-83.
Abstract ( ) PDF ( 130KB ) ( ) 　　
        Along with the establishment of the ethylene projects, it is practically meaningful to give an impetus to the regional economy and to speed the upgrade of the traditional industry by studying the ethylene projects .Through searching , there are only theoretical articles to this issue in current , especially lack of demonstrative research .Using the empirical studying theory of FDI (foreign direct investment)technology spillover effect, the regional economy related to ethylene projects was divided into two parts - ethylene projects investment and non -ethylene , the technology spillover situation and other enterprises within the area was analyzed , and three empirical models to evaluate the technology spillover effect of ethylene item were constructed .The coefficient of the technology spillover effect of ethylene item is 0.15 to 0 .37 in general by the analysis of statistic software .
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Investigations of Impact of Knowledge Flows in Regional Innovation System on Economic Performance
ZHANG Rui -jun,LI Jin -ling
2007, 27 (4): 84-86.
Abstract ( ) PDF ( 141KB ) ( ) 　　
　    In the innovation system , knowledge flows gradually become the basic way of the mutual impacts which between each factor , and become the power mechanism and an important path that raises the innovation performance .On the basis of the relevant theories and methods concerned with regional economics , technological innovation and national innovation system , starting from regional innovation system , through the research of the mechanism of knowledge flows, the paper analyzes the relativity between knowledge flows and economic performance , finds out their contact and regulation , discusses the function of regional know ledge flows, which can influence the economic growth and the industrial structure .
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Dispersive Properties of Interferential Spectrometer With Polarizing Prism
PEI Fang -fang
2007, 27 (4): 87-91.
Abstract ( ) PDF ( 658KB ) ( ) 　　
 　The analytic expressions about the OPD(optical path difference)between o ray and e ray , and the dispersion of the OPD were presented .The dispersion formulas and dispersion powers of the calcite were derived by the help of curve fitting and optimizing .Then the OPD and the dispersion of the OPD were simulated by computers.The results show that for Wollaston prism spectrometer , the OPD is linear function of incidence position while the incidence position is taken as the spatial variable ; the linearity of the OPD turns worse while the incidence angle is taken as the spatial variable .The dispersion effect on Wollaston prism spectrometer with calcite exists mainly in the short -wavelength region(0 .4～ 0.7μm), and the effect in the long -wavelength region(0.7～ 1 .16μm)is small.
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A Simple Criterion for Nonsingular H -Matrix
CUI Qi,SONG Dai -cai
2007, 27 (4): 92-94.
Abstract ( ) PDF ( 141KB ) ( ) 　　
　Let A=(a_{i j})∈ C^{n ×n} , if the reexists α∈(0, 1)which can make a_ii ≥αRi(A)+(1 -α)S _i(A)be right for i ∈ N ,then A is called a α-diagonally dominant matrix .Ex tend the concept to generalized α-diagonally dominant matrix , and apply the concepts and proper ties of α-diagonally dominant matrices, irreducible α-diag onally dominant matrices and gene ralized strictly α-diag onally dominant matrices to obtain a simple criterion of a nonsingular H-matrix .These conclusions not only enrich and improve the theory of α-diagonally dominant matrices and nonsing ular H-matrix , but also lay a solid foundation for the research of computational mathematic , matrix theory , control theory , mathematical economics , etc .
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