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    25 October 2005, Volume 33 Issue 10
    Wu Jian-qing Xin Chong-fei Yang Jin-ping Zhang Yi Li Bin
    2005, 33(10):  1-4. 
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    Lead-free frit was first prepared by the melting method.Then,the effects of CeO2,Li2O and ZrO2 on the performances of the frit,such as the maturing temperature range,the thermal expansion coefficient,the flexural strength and the chemical stability,etc.,were investigated by using the high-temperature microscope,the therm alexpansion analyzer,XRD and SEM.The results indicate that(1)with the addition of CeO2,the initial fusing tem-perature of the frit decreases,while the maturing temperature increases;(2)both the initial fusing temperature and the maturing temperature decrease by 30 to 50℃ if 1.5% (mass fraction)Li2O is added;(3)the chemical sta-bility of the frit can be improved by adding ZrO2 to the frit;and(4)the flexural strength of the frit can be greatly improved by adding CeO2 and ZrO2 together.Finally,a kind of excellent frit with a maturing temperature of 850 to 900℃ .a flexural strength more than 70 MPa and a mass loss in chemical solution less than 100 μg/cm was pre-pared.

    Wang Zhai-min Pmg Bing-chu Pi Pi-hui Wen Xiu-fang Cheng Jiang Yang Zhuo-ru
    2005, 33(10):  5-8. 
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    The effects of three catalysts and their contents on the modification reaction of o-cresol formaldehyde epoxy acrylate with maleic anhydride were investigated.The process of UV curing of the ink prepared by the acid-modified o-cresol form aldehyde epoxy acrylate was then characterized by means of fTrIR.Moreover,four prepoly-mers with different structures were synthesized.The influences of these four prepolymers and the monomer content on the surface drying property of the ink membrane were finally analyzed.The results show that:(1)the catalytic activities of the three catalysts decrease in the order of tetramethyl ammonium chloride,triphenyl phosphorous,trie-thylamine;(2)with the appropriate content(mass fraction,the same below)of tetramethyl ammonium chloride,that is,1.0% ,the prepared ink possesses good photosensitivity,with the convemion of unsaturation bonds amoun-ting to 81.78% after a 15-second exposure;(3)the ink with the acid-modified o-cresol formaldehyde epoxy acry-late as the main body is of good surface drying property,whose resolution achieves 50 Ixm;and(4)with the mono-mer content ranging from 10% to 15%,the ink membrane possesses good surface drying property/

    Fang Yu-tang Yi Li-qun Liu Yan-shan
    2005, 33(10):  9-13. 
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    Novel Ti-doped silica gel adsorptive materials were prepared by treating ceramic fiber paper with the sequential impregnation of water glass and the aqueous solution of acidic titanium salt.The optimal reaction conditions were accordingly obtained,that is,30% (mass fraction)of the titanium salt content,1 mol/L of the additional sulfutic acid concentration,80℃of the impregn ation temperature and 120 min of the impregnation time.It is found that the characteristic peak of Ti- O-Si linkage in the Ti-doped silica gel is shown on the FTIR spectra at the wavenum-ber of 954 cm-1.Th e SEM photograph reveals that the Ti-doped silica gel well scatters on the surface and in the apertures
    of the ceramic fiber paper;an d the porous medium surface area an alysis shows that the mesopore is dominant in the Ti-doped silica gel.Th e present study also presents an X-ray EDS analysis of the existence and content of Ti4+ in the adsorptive materials.It is concluded that,compared with the original silica gel,the Ti-doped silica gel is of greater
    specific surface area,pore volume and adsorptive capacity.and possesses stronger thermal stability because of the formation of Ti- O- Si linkage on the surface.

    Lu Di-fen Hu Hai-peng Wang Xiu-long
    2005, 33(10):  14-18. 
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    In order to prepare mineral admixture with excellent property for concrete,a new type of multi-compo-nent mineral material with large content of fly ash as the substitute was investigated by orthogonal experiments.Without any activator,fly ash,granulated blast furnace slag and some natural mineral powders were mixed and theproportion was optimized,which results in a synergistic effect of the components.Moreover,due to the compoun-ding effect and the grinding effect of different components,reasonable particle size distribution and better dense packing efect were obtained,resulting in a g0od combination of all the different components,thus improving the performance of the mineral admixture and reducing the cost.Experimental results show that,when the content of the fly ash-based admixture is 50% (mass fraction)in cement,the 7-day and 28-day activity indexes respectively achieve 56.26% and 76.6%.and that the water consumption for the standard consistence of the muhi-component cementitious powder decreases,while the slump and strength of concrete increase.

    Sun ji-feng Wang Cheng-qing
    2005, 33(10):  19-23. 
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    A tracking method for motion objects is proposed based on the feature-point optical flow,which is then applied to the real-time tracking of moving vehicles in the intelligent traffic system.In the proposed method,the Kalman filtration and the polygonal tracking strategy are adopted,thus simplifying and stabilizing the tracking.Si-mulated results indicate that the proposed method can accurately determine the maneuvering target,extract the fea-ture points,implement the computing and clustering of the feature-point optical flow and recognize moving objects.Moreover,it is of less computation and is easy to implement.

    Su Jin-dian Guo He-qing Gao Ying
    2005, 33(10):  24-28,43. 
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    In order to solve some trust-related security problems existing in curent Web service networks and im-prove the security and reliability of W eb services,this paper proposes an improved adaptive trust model of Web services,namely,iWSTrust,and the coresponding evaluation algorithms of its trustworthiness an d reputation. In iWSTrust,the subjective logic is first used to model and reason the trust for the entries in Web service networks.and a trusty third party is added to store the trust inform ation.Th en,by considering the related entities in the Web service environment,the trust relationships involved in a typical interaction are analyzed.Moreover,diferent types of service requesters are distinguished,which enables the trustworthiness and reputation of entities to self-adapt with the increase of interaction experience.Th e results of simulated experiments show that iW STrust ,to some extent,can decrease the number of accessing vicious entities and punish deceitful entities accordingly.

    Song Zhu-mei Li Di
    2005, 33(10):  29-33. 
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    With the aim of investigating domain-extending technologies for the embedded control of equipment, the model-integrated computing theory is applied to construct the modeling language of the embedded system.For the signal-processing subsystem,a meta-model is established in terms of four aspects , that is,class diagram ,visualization,attributes and constraints.The associated model interpreter is modified according to the proposed meta-model.Then,by means of the meta-model interpreter,a graphical modeling language is driven from the meta-model.Based on the associated modeling language,two signal processing models are built and transferred into two applications,respectively.The results indicate that the proposed method is feasible for the rapid development of domainspecific applications.

    Liang Ji-zhao Li Feng-hua
    2005, 33(10):  34-37. 
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    The heat transfer mechanism of the polymer composites filled with hollow micro.spheres is analyzed in this paper.It is argued that heat transfer mainly includes the thermal conduction between the solid and the gas,the thermal radiation among the hollow micro-sphere surfaces.and the natural therm al convection of the gas in the hollow mi.cro.spheres.Th en.a theoretical model of the heat transfer in the composites is established based on the laws of the minimal thermal resistance and the specific equivalent therm al conductivity.An equation for the equivalent therm al conductivity(keff)is derived,by which the equivalent thermal conductivity of the polypropylene composites filledth hollow mi cro.spheres is estimated.Th e obtained results are finally compared with the numerically simulated ones.It is concluded that the estimated equivalent thermal conductivity is of the salne variation as the simulated one at a lower filler content(φ f≤20%,volume fraction),and that the equivalent thermal conductivity linearly decreases with the increase of the filler content as well as with the increase of the filler size at a constant filler content.

    Ma Hua-sheng Zhang Bo Zheng Jian-chao
    2005, 33(10):  38-43. 
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    The operation principle of the phase-shift-controlled double-full-bridge power electronic transformer is an alyzed,and,by the analysis of the state space model,an equivalent tran sform er model and its corresponding out-put characteristic curve are obtained.Moreover,the expressions of both the equivalent transfer ratio and the inner resistan ce are deduced.Thus,it is proved that in term s of the essential features of the proposed model.the conven.tional transform er can be replaced and extended by the power electronic transform er.The corectness of the theoreti-cal an alyses is finally verified by simulated experiments.

    Deng Hua-qiu Long Qing-yun Wu Jun-fang
    2005, 33(10):  44-47. 
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    In order to analyze the effects of the parameters of the forward-pumped Raman fibre amplifier on the gain,this paper presents the analytical solution to the output signal and the theoretical expression of the gain by solving the forward-pumped coupling equations of the amplifier.Then,the efects of the fibre length,the initial signal power,the initial pump power,the effective fibre area and the Raman gain coefficient on the gain of the amplifier are investigated in the condition that the parameters are all of their typical values.Some of the findings are consistent with the experimental results in the literature.It is finally concluded that the gain characteristics of the amplitier can be optimized based on the different efects of the parameters,thus improving the gain as well as amplifying the performan ce of the amplifier.

    Pan Zhao-qun Zhang Yan-qing Deng Xian-he Chen Hai-hui
    2005, 33(10):  48-51,89. 
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    A mathematical model of the energy consumption for the muhistaged spraying rotating packed bed was presented by theoretical analyses,and was then verified by experiments carried out on a self-developed rotating packed bed by way of measuring the power consumption with an ammeter. Moreover,an equation of the total energy consumption was induced according to the experimental data.The results show that the liquid flux . the rotating speed of the bed,the rotating manner and the structure of the rotors greatly influence the energy consumption,while the gas flux does not.It is also indicated that less friction and better rotating manner can 0bviouslv reduce the total energy consumed by the working rotor.It is finally concluded that the rotating packed bed can greatly enhance the transfer process with less energy consumption.

    Liu Ting-jin Mo Hai-hong Zhu He-hua
    2005, 33(10):  52-56. 
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    A mesoscopic numerical model to investigate the failure process of heterogeneous concrete is established,in combination with an elastic-plastic anisotropic damage model for the mesoscopic element of concrete.The proposed modelis based on the mesoscopic structure characteristics of concrete.in which the Weibull stochastic distri.bution function is adopted to introduce the heterogeneity of concrete.By using the established mesoscopic numerical model,numerical experiments about the progressive failure process of a double-edge-notched specimen under biaxial loading are then carried out.The results are basically consistent with those of Suaris’s experiments,thus verifying the rationality of the proposed model.Th e present research has provided a new numerical method for investigating the progressive failure process and the failure mechanism of concrete.

    Zhang Gong-xin Dong Zhi-liang Mo Hai-hong Zhao Jian-guo
    2005, 33(10):  57-61. 
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    The application ranges of the vacuum,the vacuity,the negative pore-water pressure,the difference in pore-water pressure and the negative pressure are discussed based on the basic conception and physical characteris-tics of these items.It is concluded that(1)the vacuum and the vacuity only describe the gas state;(2)the nega-tive pore-water pressure and the difference in pore-water pressure only describe the liquid state;and(3)the nega-tive pressure can describe both the gas state and the liquid state.Moreover,it is suggested that,during the monito-ring of vacuum preloading,what is meant by the negative pressure should refer only to the negative excess hydro-static pressure for the purpose of avoiding the confusion.It is also indicated that the negative pressure is only a part of the difference in pore-water pressure.The measurement techniques and corresponding resuhs of the vacuity are finally investigated,indicating that the vacuum meter should be used to measure the vacuity under the membrane,and that the piezometer should be used to measure the negative pressure at the observation point under the ground-w ater

    Huang Xiao-qing Zhang Xiu-li Tang Li-qun
    2005, 33(10):  62-66. 
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    In order to investigate the impact response of W-beam guardrail system and the influence of the interac-tion among the spans on the deformation and the impacting force,the impact experiment of the semirigid three-span scaled-down guardrail system was designed and executed,with a scaled-down ratio of the specimen size to the ac-tual size of 1:3.75.A comparison between the three-span and single-span guardrail systems was then ca~ied out in such aspects as the deform ation,the impacting force,the velocity and the energy absorption,etc.The contributions of each part of the guardrail system to the energy absorption were finally calculated.The results indicate that the three-span guardrail system absorbs more energy with greater uniformity and rationality than the single-span guard-rail system does.The proposed testing method and the corresponding conclusion lay a foundation for the optimiza-tion of gu ardrails in engineering.

    Zhang Xiao-qing Huang Xiao-qing Tang Li-qun
    2005, 33(10):  67-71. 
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    A finite element model of the three-span scaled-down W-beam guardrail system under impact loading is established in this paper.The dynamic response of the guardrail system under the impact loading is analyzed by using the LS-DYNA finite element code,and the instantaneous deformation process of each part is revealed,inclu.ding the bending of the W-beam,the extruding of the blocks,the torsion and bending of the posts.Then,the varia-tions of the acceleration and the velocity are investigated,showing that the impact acceleration of the loading head rapidly increases at the beginning and then gradually decreases to zero,while at the same time,the impact velocity gradually decreases to a reverse value.Moreover,the energy-absorbing characteristics of the guardrail system in the impact process are analyzed.It is found that the impact energy of the loading head mainly translates into the inter-nal energy at each part of the guardrail system and the residual kinetic energy at the loading head,and that the blocks and the W -beams are the main parts absorbing energy .The analytical results are finally compared with the experimental ones and they are found to be consistent,thus revealing the validity of the proposed model.

    Zeng Xin-an Qin Frank G. F. Li Zhong-yan
    2005, 33(10):  72-77. 
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    A pilot-scale reactor for continuously generating sodium hypochlorite(NaClo),which is applied to the cleaning-in-place(CIP)and the sterilizing-in-place(SIP),is introduced in this paper.The electrolytic cell of the reactor is constructed as a tubular electrochemical reactor with a nylon net membrane between the electrodes and with a layer of rare-earth metallic oxide,RuO2,as the active catalytic coating on the titanium anode surface.The performance of this generator is then analyzed from the point of view of reaction engineering.Experimental results indicate that the electric current eficiency of the reactor is above 82% .Biological study shows that the sterilizing water with the available chlorine content can effectively kill most microorganisms on the walls of food equipment.

    Yang Guo-long Zhao Mou-ming Liu Tong-xun Xu Xin Peng Zhi-ying
    2005, 33(10):  78-83. 
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    The soy pmtein(SP)supernatant,obtained by the centrifugation of defatted soy flour suspension in preweighted reverse osmosis water at pH 8.0 after continuous agitation for 40min,was selectively hydrolyzed by protease in certain conditions,and was then subjected to uhrafihration for fractionation.The retentate was ly-ophilized to obtain modified soy protein with the protein content(mass fraction,below the same)increasing from 52.6% to more than 78% .and the yield more than 80%.The results of SDS-PAGE show that the soy
    protein modified by Alcalase 2.4L mainly contains the basic subunits of glycinin,and that modified by fungal protease concentrate mainly contains the acid and basic subunits of glycinin.

    Gao Xiang-yang Lin Bi-run Yao Ru-hua Chen Nian
    2005, 33(10):  84-89. 
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    The ultraviolet(UV)and fluorescent spectra of Wanlongmycin were first investigated.with a relatively strong UV absorbance occurring within the range of 1 90 to 300 nm in alcohol solvent. and two highest peaks located at the wavelengths of 202 nm and 228 nm.Then.the wavelengths of 290 nm and 330 nm were respectivelv selected as the optimum fluorescent excitation and emission wavelengths to study the interaction between Wanlongmycin and metal ions.The results indicate that,in the presence of Ca2+, Al3+ ,Cu2+ and Mg2+ ,a decrease in peak intensity and a violet shift of the UV spectrum of Wanlongmycin, as well as an obvious fluorescent quenching effect,can be observed,which means that Wanlongmycin can interact with these metal ions to form a stable Wanlongmycin-metal ion complex. Moreover,it is indicated that Zn2+ with different concentrations hardly influences the UV spectrum,the relative fluorescent intensity and the location of the peaks. which means that there is no interacti0n between Wanlongmycin and Zn2+.

    Liu Dong Li Shi-min Zhang Li-jun Tang Yu-qian Liang Shi-zhong
    2005, 33(10):  90-94. 
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    Five angiotensin-converting enzyme inhibitor peptide(ACEIP)sequences were first designed and synthesized according to the relationship between the function and the structure of ACEIP.Next,the optimal peptide,namely,P3(six-amino-acid sequence)was determined by the bioactivity measurement and the digesting test in vitro.It was then jointed at the specific enzyme cleavage site to construct a six-copy fusion peptide.The corresponding coding gene was cloned into pGEX4T-2.The fusion expression vector of pGEX4T-2-ACEIP was finally transformed into Escherichia coli BL21.The results of the double enzyme-cleavage,PCR an d the sequence analysis all indicate that the recombinant plasmid pGEX-T-2-ACEIP is successfully constructed.

    Hu yong-you Liang Hui-qiang Luo Huai-qing
    2005, 33(10):  93-97. 
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    In order to seed aerobic nitrated sludge in an anaerobic sequencing batch reactor(ASBR),the anaero-bic ammonium-oxidized sludge(ANAMMOX)was successfully enriched at(30±1)oC after a 1 42-day cultivation,with the influent pH value ranging from 7.2 to 7.8.Experimental results indicate that,with a hydraulic settling time of 1.2d and a volumetric loading rate(calculated with the content of N)of 0.431 8 kg/(m3 ·d),the maxi-mum and average removals of the total nitrogen respectively achieve 93.3% and 80.5% .while the maximum re-movals of NH4+-N and NO2--N respectively achieve 93.9% and 99.8% .averaging 81.2% and 85.7% respective-ly.In addition,the mole ratio of the removed NH4+-N to the removed NO2--N in the ANAMMOX process is 1:(1.387±0.024),and the anaerobic ammonium oxidation is found to be the main reaction in the ASBR,which means that ASBR is one of the useful tools to enrich the ANAMMOX sludge.

    Zhang Xin-ya Shen Hui-fang Huang Hong Li Yong-jin Lan Ren-hua Chen Huan-qin
    2005, 33(10):  98-102,107. 
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    Styrene/acrylate emulsion was synthesized by merization,with styrene(St),methacrylic acid(MAA) the semi-continuous technique of seeded emulsion poly-or acrylic acid(AA),butylacrylate(BA)and methyl-methacrylate(MMA)as copolymerization monomers.The efects of the aminating temperature.the adding manners and the contents of AA and MAA on the viscosity,the particle size and the carboxyl distribution of the emulsion were then discussed.Moreover,the alkali-thickening mechanism of the emulsion was briefly analyzed. Experimen.tal results show that:(1)at an aminating temperature of 60℃,preferable alkali.thickening effect is obtained.and the particle size is reasonably reduced;(2)different adding manners and adding time of AA and MAA may resuIt in different distributions of carboxyl groups in the emulsion particle as well as different alkali.thickening properties;and(3)the enrichment of carboxyl groups on the surface of emulsion particles can be achieved by a specific poly.merization technique.

    He Chun-xiong Chen Shu-min Yao Yang-xin
    2005, 33(10):  103-107. 
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    The existence for the solutions to the quasilinear subelliptic partial differential equations in a weighted Sobolev space is investigated in the condition that the nonlinear term is odd. Under comparably weaker conditions,the corresponding functional is proved to satisfy the Cerami condition. Moreover,by using the Fountain theorem of Bartsch,the existence of infinitely many solutions with large energy for the equations are obtained.

    Ding Wei
    2005, 33(10):  108-111. 
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    In order to overcome the dificulty in the sequencing of several groups of tasks,an improved longest processing time first(L )algorithm is proposed,and the Gmax problem of 4 groups of workpieces on one general-purpose machine and four special-purpose machines is investigated.In this investigation,the principles of“maximum relative machining time’’and“being disengaged first of all”are adopted and the four special-purpose machines are at the same speed.Then,by using the proposed approximate algorithm,the ratio of the approximate solution T to the optimal solution T* is evaluated,i.e.T/T*≤5/4,which means that the time cost with approximate sequencing is five fourths of that with optimal sequencing.

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