30 December 2013, Volume 44 Issue 24
    

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    研究 开发
  • Electronic structures and optical properties of (L12, D022)-TiAl3 and L12-Ti (Al, Pt)3 by first-principles calculation
    Duan Yong Hua
    . 2013, 44(24): 1-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    Based on the first-principles density functional theory (DFT), the electronic structures and optical properties of cubic L12-TiAl3 and L12-Ti (Al, Pt)3 and tetragonal D022-TiAl3 are calculated by using the generalized gradient approximation (GGA) and plane wave pseudopotential method. The calculation results show that the valence and conduction bands of L12-TiAl3 and D022-TiAl3 near the Fermi energy of are composed of Ti 3d and Al 3p orbits while Ti 3d and Pt 6s orbits for L12-Ti(Al, Pt)3; the dielectric functions, refractive indexes, absorption coefficients and reflectivity of L12-TiAl3, L12-Ti (Al, Pt)3 and D022-TiAl3 are calculated, respectively.
  • Investigation of Polyhydroxy Polyamino Complexing Agent on CMP of TSV Wafer
    . 2013, 44(24): 2-0.
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    A polyhydroxy polyamino complexing agent (FA/O) has been developed and applied in through-silicon-via (TSV) chemical mechanical planarization (CMP). The comparision experiment of FA/O with another normal complexing agents has been carried out, the results reveal that FA/O has a efficient effect on removal of copper in alkaline condition, few FA/O added in slurry will significantly improve the removal rate of copper. However, when we continue to add FA/O in solution, the removal rate of copper will stay leveling. The result of TSV Cu CMP reveal that the removal rate of copper can be achieved 2.8μm/min, it can meet the requirement of development of microelectronic technology.
  • The Influence of Oxygen Content on the Structure and Properties of Silicon Oxynitride (Si-O-N) Fibers
    ;;;;An-Hua LIU
    . 2013, 44(24): 3-0.
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    In this work, PCS fibers, cured with different oxygen contents, were conducted by pyrolysis nitridation for carbon removal and amination in the ammonia atmosphere, and then through condensation/nitridation reaction at high temperature in the nitrogen atmosphere to produce silicon oxynitride fibers. Results of XRD, EPMA and TEM showed that, all of the elements in the ceramic fibers dispersed uniformly, and as the oxygen content in the cured fibers increased, it also increased in the ceramic fibers but with a drop in mechanical properties. However, the ceramic yield rose first and then fell because of the phase decomposition at high temperature. Indicated by the results of XRD and TEM, even after heat treatment at 1500oC, ceramic fibers were still amorphous regardless of how much the oxygen content was. The oxygen maybe play a role like impurity in the fibers, which inhibites the crystallization of silicon nitride.
  • Force-sensitive properties of FeCuNbSiB powder/IIR composite film
    Fu Yuan;Zhenghou Zhuqiao bao ying
    . 2013, 44(24): 4-0.
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    Abstract: The composite film was prepared by FeCuNbSiB powder as compound phase and silicone rubber as matrix phase. The content of powder is 80% and the thickness of film is 200μm. The impedance- Z and stress- σ of film were tested by TH2816LCR digital bridge when frequency was 1kHz. LYYL-500N high-grade type microcomputer control pressure testing machine was used to program control loading. The film system was connected by capacitance way, The force-sensitive properties were studied when stress loading and unloading was continuous or retentive. The results show that when frequency is 1kHz and stress is 0.2~1.0MPa, the composite film has excellent force-sensitive stability and sensitivity in condition that the speed of continuous loading and unloading is lower than 0.5mm/mim and loading and unloading is retentive. The impedance is declining nonlinear with the stress increasing. The value of SI% is 6%~23%,the value of sensitivity k ranges from 1.9~0.02,the standard deviation is stability between 0.02~0.01.The film is more sensitive Increasing test frequency can improve the sensitivity of film. When stress is between 0.2~1.0MPa the elastic aftereffect phenomenon is obviously, which leads to the loading Z---σ curve and unloading is not coincident.
  • Mechanism of Co-TiO2 Catalyst with Both Visible Light Photocatalytic and Fenton-like Catalytic Activities
    ; ;;;
    . 2013, 44(24): 7-0.
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    The Co-TiO2 catalysts were prepared by the sol-gel method, and their catalytic activities were measured by the degradation of phenol with different Co2+ doping dosage and calcinations temperature. The catalytic mechanism was studied through XRD, UV-DRS, XPS and degradation tests. The results showed that the catalysts represented the visible light photocatalytic and Fenton-like catalytic activities. When the cobalt doping dosage was 1.0% and the calcinations temperature was 500℃，the degradation rates of phenol were reached 52.3% of photocatalytic process under visible light and 65.3% of Fenton-like reaction.
  • Research on Viscosity of Magnetic liquids in Magnetic Field
    ;;Wenrong Yang ;;Li De Cai
    . 2013, 44(24): 8-0.
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    With the development of research about sensors based on magnetic fluid, the effect which is produced by the viscosity of magnetic liquid on dynamic characteristics of sensor is paid more attention. The changing of viscosity with the external factors become the hot spot. This paper studied magnetoviscous characteristic of magnetic liquid and other affecting factors to influence its viscosity. And the device is designed based on principle of Helmholtz Coils, which could produce adjustable uniform magnetic field. The coils are placed outside the rotational viscometer, measured viscosity change of magnetic fluid under a certain magnetic field. And using the vertebral plate viscometer, the viscosity changes with temperature and shearing rate is studied. The results show that the viscosity of magnetic fluid will increases with an increase of magnetic field, and be affected by the angle between the direction of magnetic field and scroll vector of magnetic fluid. The viscosity decreases with the increasing of temperature. The liquid is non-Newtonian flow, the apparent viscosity of which reduces with increasing of shearing rate. These results are beneficial to the dynamic characteristics research on sensors.
  • The study of nitrile rubber /organic small molecule blending on the heat stability
    ;;;;;Min-Hao ZHU
    . 2013, 44(24): 9-0.
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    The damping mechanism of the nitrile rubber (NBR) / organic small molecule AO-2246 blending was investigated due to the blending have not a good excellent thermal stability property, which was studied by the Dynamic mechanical analyzer (DMA), Fourier Transform Infrared (FTIR), X-ray diffraction (XRD), Scanning Electron Microscope (SEM),etc.. The results showed that the NBR/AO-2246 blending was displayed an outstanding damping property but a poor heat endurance performance when there was a rich content of AO-2246. With the increase of annealing temperature, a gradual decline in the damping capacity was apparently related to the disappeared of the hydrogen bond which can induce a large amount of crystals from AO-2246. These crystals could further damage the damping performance. In this study, the results from SEM indicated crystals may be prone to generate on the internal interfaces attributed to the interface effect. It was found the crystal morphology was also changed with increasing annealing temperature. This indicated the crystal structure is unstable which was the results from the gradually disappeared of the hydrogen bond.
  • The Effect of Surfactants on the Aggregation Behavior of Phthalocyanine Zinc (II) Bearing Poly (aryl benzyl ether) Dendritic Substituents with Carboxylic Terminal
    ; ;;
    . 2013, 44(24): 10-0.
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    The interaction between the phthalocyanine zinc (II) bearing poly (aryl benzyl ether) dendritic substituents with carboxylic terminal ( ZnPc(COOH)4, G1-ZnPc(COOH)8 and G2-ZnPc(COOH)16) and cationic surfactants (cetyltrimethyl ammonium bromide (CTAB)) were studied by fluorescence and UV/Vis spectroscopic methods. ZnPc(COOH)4, G1-ZnPc(COOH)8 and G2-ZnPc(COOH)16 mainly existed as a dimer at 625 nm in aqueous media, but they mainly exhibited as monomers at 685 nm with addition of CTAB. As the concentration of CTAB increased, the intensity of the monomeric absorption peak increased, while that of the dimer peaks decreased gradually. Meanwhile, the fluorescence intensity of ZnPc(COOH)4, G1-ZnPc(COOH)8 and G2-ZnPc(COOH)16 also markedly enhanced. Therefore, the aggregation behavior of these water-soluble dendritic phthalocyanines can be disrupted effectively by addition of CTAB. This maybe due to the electrostatic interaction between the positive charges of the CTAB and negative charges of the dendritic phthalocyanine, leading to dis-aggregation of the dendritic phthalocyanine. The nanoparticles were formed by encapsulation of water-soluble dendritic phthalocyanines into the CTAB micelles. The diameters of nanoparticles were studied by Zetasize particle size analyzer. The average sizes of nano-particles were in the range of 5-30 nm. The size of nano-particles increased with the increasing the concentration of CTAB while decreasing with increasing of the dendritic generation. This will provide a useful method for solving the aggregation problem associated with phthalocyanine, and showed potential application in various photophysical and chemical applications.
  • THE SYNTHESIS OF A NEW TYPE OF TERT-BUTYL-MODIFIED BISMALEIMIDE RESIN
    CUI Tian-fang
    . 2013, 44(24): 11-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    In order to improve the monomer solubility of bismaleimide resin, lower the resin prepolymer’s viscosity and make the bismaleimide resin easy to manufacture by the RTM molding process which is knowen as a new low cost process, 3,3’-ditert- -butyl-4,4’-diphenylmethane bismaleimide (BBDM). The chemical structures of the products were confirmed by infrared spectroscopy and elemental analysis. Solubility experiments show that the solubility of the new resin monomer is significantly improved in common solvents. Data of the prepolymer viscosity and melting points show that the viscosity of the prepolymer meets the requirements of the resin transfer molding process (RTM) (0.20 ~ 0.28Pa ? s) and the heat resistance of original resin has been also retained. With the development of our society, more and more high performance composite materials used in special areas, such as aerospace, high-temperature protec- tion industry and microelectronic field, are needed.
  • Investigation on autogenous shrinkage of high strength concrete with new internal curing materials
    Rongjin Liu
    . 2013, 44(24): 12-0.
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    Internal Curing has become a hot topic in mitigating autogenous shrinkage of High Strength Concrete, HSC. In this thesis, relationship between autogenous shrinkage and new Internal Curing Materials was carried out and internal curing mechanism was further investigated. The results show ICM that provides useful reference for solving early-age shrinkage. When the amount of ICM 20 to 35 kg/m3, the particle diameter below 100μm, autogenous shrinkage of HSC was well mitigated. When Manganese slag powder and Fly Ash in concrete, its can play an assembling role on internal curing as ICM. MIP analysis confirmed that mitigation of autogenous shrinkage lies in reducing the amount of shrinkage adversely 9~50nm capillary pores, and increasing the number of below 9nm gel pores by Internal Curing.
  • Synthesis of the Silica@Graphene Oxide microspheres with Core-Shell Structure as Drug Carriers
    ; ;;;
    . 2013, 44(24): 13-0.
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    The silica@graphene oxide (SiO2-NH2@GO) microspheres with core-shell structure were synthesized through the electrostatic interactions by encapsulation of graphene oxide on the surface of amino modified silica microspheres. The as-prepared microspheres were characterized by FTIR, SEM, TEM and UV, etc. The results show that the SiO2-NH2@GO microspheres are monodispersed with the diameter of 550 nm. GO wrapped on SiO2 surface evenly which were examined by SEM and TEM. Compared with pure SiO2, the drug loading of SiO2-NH2@GO microspheres is increased highly from 42.9% to 68.8% after immersed in ibuprofen solution, the 92% drug is released after soaked for 24 h and the administration time is prolonged about 20 h. This implies that the monodispersed SiO2-NH2@GO microspheres synthesized in this work have potential usage as drug carriers in the biomedical fields.
  • Dynamic sorption and hygroexpansion of wood by humidity cyclically changing effect
    ;
    . 2013, 44(24): 14-0.
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    In order to investigate dynamic sorptive and hygroexpansive behavior of wood under cyclic relative humidity condition, poplar ( Populus euramericana Cv. ) specimens, in the size of 20mm ( T )× 20mm ( R )× 4mm ( L ) and 20mm ( T )× 20mm ( R )× 10mm ( L ), were exposed to sinusoidally relative humidity between 45-75% at 25℃ for 1, 6, and 24 h. Moisture changes and radial and tangential dimensional changes measured during the cycling gave the following results: moisture and dimensional changes of the specimens were generally sinusoidal but lagged behind the imposed humidity. The phase lag decreased and the amplitude increased with increasing cyclic periods, while specimen thickness had an opposite effect on the phase lag and amplitude. Under dynamic conditions, the specimens showed sorption hysteresis and swelling hysteresis as well, and moisture sorption coefficient and humidity expansion coefficient of them were in positively correlation with cyclic period, but inversely related to specimens thickness. The dynamic sorption model proposed by a previous study based on softwood obtained good agreement with experiment results in this study for hardwood species and different specimen thickness.
    • 工艺 技术
  • The Extension Measurement of the Parameter of Piezoelectric Materials on Spectrum Analysis
    Yong-Sheng BAO;
    . 2013, 44(24): 15-0.
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    To solve the problem of accurate characterization and effective detection for piezoelectric material parameters, it is proposed that establishment of the spectrum analysis of a piezoelectric material response signal in an extension detecting system creates a new method for detecting the demand parameters of piezoelectric materials effectively and accurately. And piezoelectric filter based on the unique characteristics of materials, the spectrum of piezoelectric material extension detecting signal is analyzed by the most appropriate expansion in frequency. According to the spectrum spread, the sample characteristic resonant impedance and other demand parameters of piezoelectric materials are detected effectively and accurately. There are the more intuitive detection of characteristic resonant impedance of piezoelectric materials from the spectrogram and the accurate detection results. And we try to make a general discussion on multiple signal feature fusion excitation piezoelectric material parameters detection system.
  • Magnetic Properties of Nanocrystalline BaFe12O19 Prepared by Ultrasonic-Solid Phase Synthesis
    ;
    . 2013, 44(24): 16-0.
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    Ba(OH)2/Fe(OH)3 mixed powders were processed by Ultrasonic for 8h, and then the resulting product was used to prepare the nanocrystalline BaFe12O19 particles with the hexagon shape.The TG-DTA、XRD and TEM anaylized the mechanism of reactions, compenents and microstructure of products.The vibrating specimen magnetometer(VSM) tested the Magnetic Properties of products. The results show: (1) the ultrasonic method could lower the reaction temperature (2) the optimal conditions are obtained with the magnetic parameters of σs =56.100 emu/g,σx =28.364 emu/g, and Hc =2880.9Oe as the following condition parameters.The ratio of Fe to Ba is 10, and the reactioin temperature is 900℃.The resulting products are more pure BaFe12O19 particles with the hexagon shape and excellent crystallinity, which are in the single phase.The Magnetic Properties in this papre are better than the normal solid phase synthesis.
  • Fabrication of stainless steel surface with high adhesive superhydrophobicity by femtosecond laser combined hydrothermal method
    WU BO;Zhou Ming ;
    . 2013, 44(24): 17-0.
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    High adhesive superhydrophobicity film has been prepared on 316L stainless steel surface by femtosecond laser combined hydrothermal method. Firstly, periodic spikes on micron scale were fabricated with laser fluence of 2.4 J/cm2 in high vacuum. Secondly, a seed layer was prepared on the microstructured surface by magnetron sputtering. Finally, ZnO nanorods film was prepared on the seed layer by hydrothermal method. The microspikes and ZnO nanorods composed a dual-scale structure. SEM and XRD results reveal that the reaction is ZnO crystal with hexagonal wurtzite structure. The apparent contact angle on the dual-scale structure is 160.2 °. Furthermore, the film has a high adhesive force to water. Based on the microstructure geometric model and hypothetical wetting state, the computational formula of apparent contact angle was produced. The calculated value accorded well with the experimental result. We provided an effective method to fabricate film with high adhesive superhydrophobicity on stainless steel surface.
  • Study of Preparation and Photocatalytic Activity of PbS/K2La2Ti3O10
    . 2013, 44(24): 18-0.
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    A series of PbS/K2La2Ti3O10 composite photocatalysts with different PbS content were prepared via a facile precipitation method. The prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray energy dispersive spectroscope (EDX), X-ray fluorescence spectrometer (XRF), ultraviolet-visible diffuse reflection (UV-Vis), X-ray photoelectron spectroscopy (XPS) and photoluminescence measurement (PL). The photocatalytic activities of the catalysts were evaluated by photocatalytic degradation of Rhodamin B under visible light irradiation. The effect of PbS content and dosage of catalyst for photocatalytic degradation Rhodamin B were also investigated. The results revealed that the PbS/K2La2Ti3O10 composites greatly improved the photocatalyst activity under visible light. The photocatalytic activity of degradation of Rhodamin B for 0.35 g PbS(25 wt.%)/K2La2Ti3O10 composite photocatalyst was 71.4% under visible light irradiation for 2 h.
  • Preparation and adsorption of Ni(Ⅱ) of PVDF/Modified attapulgite composite membrane
    ;;zhao yi ping ;;
    . 2013, 44(24): 20-0.
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    In this work, attapulgite was modified by acidification, organic pretreatment and load the tannin acid on the attapulgite by formaldehyde, respectively. Then PVDF/Modified attapulgite composite membrane was prepared by the method of phase inversion. The structure and morphology of the modified attapulgite was characterized by Fourier transform infrared and Transmission electron microscope, and the adsorption of Ni(Ⅱ) was studied by the method of Ultraviolet absorption. The results showed that composite membrane filled with the tannic acid-modified attapulgite could remove the Ni(Ⅱ) in the aqueous solution effectively, and the absorption increased by 34% than the membrane filled with pure Attapulgite Modified.
    • 综述 进展
  • Research Progress on Surface Biomodification of Cardiovascular Implanted Biomaterials
    ;
    . 2013, 44(24): 21-0.
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    Surface modification is one of the core technologies in the field of biomedical materials, its fundamental purpose is to make the surface of the biological material has better biocompatibility. Presently, various surface modification has been developed by different groups, and different methods of surface modification is selected in terms of the application fields and the faced problems of biomaterials, including reducing protein adsorption and coagulation, controlling cell adhesion,growth and differentiation, and improving the mechanical properties, The surface modification technology of cardiovascular biomaterials mainly focus on improving the blood compatibility of the materials and the endothelial cell compatibility, and can be further expanded to tissue engineering and regenerative medicine. In this paper, the research status of cardiovascular biomaterials, the surface biomodification methods and the surface modification technology for different purposes are reviewed, in order to provide important reference for the design and development of a new generation of cardiovascular implantable medical devices.
  • Research Progress of Functional Graphene prepared by thermo exfoliation method
    ;
    . 2013, 44(24): 22-0.
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    The reduction of graphite oxide is the most possible method to achieve mass production of graphene. A number of methods have been developed to exfoliate graphite oxide, and each method has its own advantages and disadvantages. Thermal exfoliation is the most economical way to obtain large quantities of graphene especially functional graphene. The exfoliation mechanism is mainly based on that the sudden expansion gases evolved into the spaces between graphene sheets during the heat-treatment process of graphite oxide. Thermal exfoliation can be realized when the sudden expansion gases pressure overcomed the attractive van der Waals inter-actions between layers. However，different oxidation and reduction processes make the functional graphene with different properties. In this paper, current research is reviewed, the mechanism of the oxidation and thermal exfoliation is discussed, which may contribute us to effectively use the controllable factors to partially control the preparation of functional graphene.
  • Development of cleaner Chrome Tanning Auxiliaries
    ;
    . 2013, 44(24): 23-0.
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    Chrome tanning is one of most mature method of the leather industry which brings good performance to resultant leather. However, the low absorption rate (about 60%) of chrome tanning agent caused serious pollution. In order to improve the absorption of chrome tanning agent and reduce the pollution of chrome tanning in leather industry, the research on cleaner chrome tanning auxiliaries becomes hot spot of leather industry. In this paper, a review and evolvement on research on cleaner chrome tanning auxiliaries such as carboxylic acid compounds, aldehyde acids, carboxylic acid polymer，natural polymer, are given. Additionally, our group has been committing to solve the pollution of traditional tanning and carrying out experiment on the chrome tanning exhausted auxiliary. A novel polymer-based montmorillonite nano composite was synthesized and applied to pickling and pickling-free tanning process separately, combined with 3% chrome tanning agent. The shrinking temperature of resultant wet-blue leather is 94℃, the amount of Cr2O3 in the tanning wastewater was decreased to 0.1g/L. Furthermore, the applying foreground of chrome tanning exhausted auxiliary in leather industry is prospected. The research on cleaner chrome tanning auxiliary is still development direction in leather industry. Attention must be paid on interdisciplinary and continuous development of new technology which have great significance to the achievement and breakthroughs.
  • Reviews on the magnetic particles of Magnetorheological fluids, Reviews on the magnetic particles of Magnetorheological fluids, Reviews on the magnetic particles of Magnetorheological fluids
    ;He Guotian
    . 2013, 44(24): 24-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    The magnetic particles of Magnetorheological Fluid demand high coercive force , low specific gravity and high stability in a wide temperature range. Based on hereinbefore, this article summarizes the characteristics of various magnetic particles, development process and preparations including chemical and physical methods. It illustrates the relation between kinds of preparations and the structure and function of the magnetic particles. Besides, the effect of magnetic particles on Magnetorheological fluids is analyzed. Finally it points the shortage of Magnetorheological fluids nowadays and make a view on the preparations, function, structure and the process. , The magnetic particles of Magnetorheological Fluid demand high coercive force , low specific gravity and high stability in a wide temperature range. Based on hereinbefore, this article summarizes the characteristics of various magnetic particles, development process and preparations including chemical and physical methods. It illustrates the relation between kinds of preparations and the structure and function of the magnetic particles. Besides, the effect of magnetic particles on Magnetorheological fluids is analyzed. Finally it points the shortage of Magnetorheological fluids nowadays and make a view on the preparations, function, structure and the process. , The magnetic particles of Magnetorheological Fluid demand high coercive force , low specific gravity and high stability in a wide temperature range. Based on hereinbefore, this article summarizes the characteristics of various magnetic particles, development process and preparations including chemical and physical methods. It illustrates the relation between kinds of preparations and the structure and function of the magnetic particles. Besides, the effect of magnetic particles on Magnetorheological fluids is analyzed. Finally it points the shortage of Magnetorheological fluids nowadays and make a view on the preparations, function, structure and the process.
    • 研究 开发
  • Crystallization kinetics of mullite from single-phase gel
    . 2013, 44(24): 25-0.
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    The crystallization kinetics of mullite from single-phase gel were studied using a non-isothermal thermal analysis method. The microstructure changes were investigated by X-ray power diffraction ( XRD ), transmission electron microscopy ( TEM ) and 27Al nuclear magnetic resonance ( NMR) spectroscopy. The results show mullite crystallization begins from 950℃. The crystallization process confroms to random unclei production and the following unclei growth model of n-dimension Avrami-Erofeev. The activation energy Ea and the pre-exponential factor A of mullite crystallization are 1086.34 KJ?mol-1 and 9.33×1042s-1, respectively. The differential expression of the corresponding mechanism function is f (α) = , n = 3.37. The nucleation rates are non-uniform which decrease with the time t in crystallization process. Nucleation is the dominant controlling step at about 980℃. Nucleation-growth becomes more predominant at about 1000℃. The rates of the grain growth are controlled by diffusion., The crystallization kinetics of mullite from single-phase gel were studied using a non-isothermal thermal analysis method. The microstructure changes were investigated by X-ray power diffraction ( XRD ), transmission electron microscopy ( TEM ) and 27Al nuclear magnetic resonance ( NMR) spectroscopy. The results show mullite crystallization begins from 950℃. The crystallization process confroms to random unclei production and the following unclei growth model of n-dimension Avrami-Erofeev. The activation energy Ea and the pre-exponential factor A of mullite crystallization are 1086.34 KJ?mol-1 and 9.33×1042s-1, respectively. The differential expression of the corresponding mechanism function is f (α) = , n = 3.37. The nucleation rates are non-uniform which decrease with the time t in crystallization process. Nucleation is the dominant controlling step at about 980℃. Nucleation-growth becomes more predominant at about 1000℃. The rates of the grain growth are controlled by diffusion.
    • 工艺 技术
  • Preparation and Characterization of Ru Nano-cluster/ Polyimide Hybrid Membrane
    ; ;zeng fan-di
    . 2013, 44(24): 27-0.
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    A series of PI films and hybrid Ru/PI films were fabricated, FTIR, TEM, XPS, DSC, WSM-20kN and Gas permeance instrument were used to characterize the structures and properties of Ru-cluster, PI films and Ru/PI hybrid films. Experimental results showed that the average diameter of the Ru particles was about 1.01nm, these Ru particles may coordinate with N and O in polyimide, and after adding Ru-cluster, the thermal and mechanical properties of the hybrid membranes increased, but the gas permeation performance(H2 and CO) decreased.
    • 研究 开发
  • Effect of composition on the thermal performance of CaO-Al2O3-SiO2-B2O3 electrical ceramic glaze
    xiao-bing ZHENG
    . 2013, 44(24): 28-0.
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    The relationship between composition and thermal behavior of electrical ceramic glazes based on CaO-Al2O3-SiO2-B2O3 system were investigated. The effect of composition on softening point , coefficient of thermal expansion and temperature difference of firing temperature and softening temperature by using the testing means of X-ray diffraction and Thermal analyzer . With the increase of B2O3 content the softening point increases first and then decreases, while the firing temperature and △T decreases. All of the firing temperature, softening point and△T increase when the content of SiO2 increases. With the increase of B2O3 content the softening point and △T have maximum and minimum value separately. As the component changes, the trend of coefficient of thermal expansion is always opposite of softening point.
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