15 August 2014, Volume 45 Issue 15

    

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工艺 技术
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  Curing and rheological behaviors of PSN/AP resin blends

  ;

  . 2014, 45(15): 1-0.

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  The curing and rheological behaviors of the ablative resin—the PSN/AP resin blends were studied through thermal and rheological analysis techniques. The DSC analysis indicated that the synchronization reaction existed between the two components in the resin system confirmed by a single exothermic peak in the curing curves; and the starting and final curing temperature were 168℃ and 338℃ determined through the extrapolation method, respectively. The chemical rheological behaviors of the resin blends couldn’t be described by a single viscosity model: the engineering and the Arrhenius viscosity equation were established separately when the temperature was below or higher than the starting curing temperature. The model values were in good agreement with the experimental results and the optimal injection temperature was at about 125℃.
研究 开发
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  Prepartion and Prpperties of LiY(MoO4)2: RE3+(RE=Eu, Sm, Pr) for White LEDs

  . 2014, 45(15): 2-0.

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  LiY(MoO4)2:RE3+(RE=Eu, Sm, Pr) red phosphors have been successfully synthesized via a mild and facile hydrothermal route. The rsulting products were characterized by X-ray powder diffraction(XRD)，scanning electron microscopy(SEM)，and photoluminescence(PL) spectroscopy. The results showed that the phosphors prepared by Hydrothermal method are with LiY(MoO4)2 crystalline phase，the phosphors with layer meso-structure and uniform particle size distribution. Eu3+、Sm3+ and Pr3+ concentration of 7%、4% and 1.5%. LiY(MoO4)2:Eu3+ powders can be excited efficiently by ultraviolet light with the wavelength of 395 nm and visible blue light with the wavelength of 465 nm. The Sm3+ and Pr3+ doped LiY(MoO4)2 phosphors can be excited efficiently by 406 nm and 453 nm, and show a strong red emission of 650nm and 657 nm. The LiY(MoO4)2: RE3+(RE=Eu, Sm, Pr) phosphors are proming as red-emitting phosphors for white light emitting diodes.
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  Synthesis and Properties of Castor Oil-based Waterborne Polyurethane-Acrylate Hybrid Latex using a Emulsifier-free Method

  . 2014, 45(15): 3-0.

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  A surfactant-free castor oil-based waterborne polyurethane-acrylic(CPUA) hybrid aqueous emulsion with castor oil-based polyurethane (CPU) as shell and polyacrylate as core was prepared via emulsifier-free emulsion copolymerization of the acrylate monomers (AC) in the presence of a commercial polyurethane dispersion as seeds,which were synthesized by a self-emulsification method,using IPDI,PCDL,DMPA,castor oil(C.O),MMA,BA as the main raw material.The effects of the content of C.O on the properties of composite emulsion and its films were studied systematically.The core-shell structure of the emulsion was observed by TEM,structure and properties of the polymer were studied by IR, XRD and TGA.The results supported the idea that when the molar ratio of -OH in C.O and PCDL was 1:3, the CPUA hybrid emulsion exhibited excellent stable performance,and the film showed outstanding water resistance and mechanical properties.IR,XRD and TEM showed certain crosslinking between CPUA, and the compatibility between hard segment and soft segment were promoted.Compared with the PUA, the synthesized CPUA hybrid film has higher thermal stability with a tensile strength 111MPa.
工艺 技术
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  Effect of carbo-nitriding treatment on cavitation erosion behavior of Ti-6Al-4V alloy

  Haibin Li; ;S.L. Zhu;Xian-Jin YANG

  . 2014, 45(15): 5-0.

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  Carbo-nitriding treatments were performed to modify the surface of the Ti-6Al-4V alloy and prepare a hard coating on the surface of the alloy. Surface morphology, microstructure, composition and Vickers microhardness of the coating were characterized by SEM, EDS, XRD and Vickers hardness testing. Subsequently, the effect of the carbo-nitriding treatments on the cavitation erosion behavior of the Ti-6Al-4V alloy was studied by an ultrasonic vibratory apparatus. The results exhibited that a dense, free-crack and hard Ti(C, N) coating was formed on the surface of the alloy samples. The coating with a fine microstructure can suppress the crack initiation at the surface, increase the crack propagation path and decay the stress field and crack propagation rate, and then absorb more cavitation energy and increase in the cavitation erosion resistance for Ti-6Al-4V alloy.
研究 开发
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  Electronic and magnetic properties of double perovskites Sr2Fe1-xCrxMoO6 : the first principles study

  . 2014, 45(15): 6-0.

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  The electronic structure and magnetic properties of double perovskites Sr2Fe1-xCrxMoO6 system in different Cr content (x = 0, 1/3, 0.5 and 1) corresponding to the Sr2Fe1-xCrxMoO6 supper cell structure were caculated by the first principle method . The calculation results showed that: the obtained lattice parameters, total magnetic moments and magnetic moments per Fe ion of Sr2Fe1-xCrxMoO6 decrease ,with the increase of Cr doping (x = 0.5), the spin-up electronic density near the Fermi energy increases, the compounds change to be metallic，but Sr2Fe1-xCrxMoO6 (x = 0, 1/3, and 1) still to be half-metalic. The calculation results coincided with the existing experiments and theories well ,which offered theoretical data for application in further.
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  Multiple scattering of thermal waves by subsurface cylinders in functionally graded materials

  Fei WANG;

  . 2014, 45(15): 7-0.

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  In this paper, based on non-Fourier heat conduction equation, employing the image method and the wave function expansion method, the multiple scattering of thermal waves resulting from a subsurface cylinder in semi-infinite functionally graded materials is investigated. According to the wave equation of heat conduction, the effects of different physical parameters on the distribution of temperature are analyzed. The thermal waves are excited on the surface of opaque materials by modulated optical beams. The cylindrical defect is taken as a cylindrical cavity under thermal insulation condition. The results of this paper can provide theoretical foundation and references for the detection of defects by using laser heating, the inverse problem, and the analysis and computation of infrared thermal imaging.
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  Analysis on Thermal Physics and Test of Specific Heat Capacity of Binary Nitrate Salt

  Shun-Xin GE; Qi Guo

  . 2014, 45(15): 8-0.

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  Binary nitrate salt is an important heat transfer medium. Mixed salt samples were prepared by molten method. The thermal physics and specific heat capacity of the mixed salt consisted of KNO3 and NaNO2 were studied and measured separately by differential scanning calorimetry (DSC) and sapphire method. The results showed that binary nitrate salt has low melting point and good thermal stability. The optimal operating temperature was between 200℃ and 430℃. The specific heat capacity of molten salt changes with the composition but changes little in the operating temperature. This experimental research provided data support for improving heat treatment process.
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  Preparation of water-soluble quantum dots and their pH-dependent behavior

  . 2014, 45(15): 9-0.

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  In this paper, due to the unique optical properties, water-soluble CdSe/CdS/ZnS multilayer core shell QDs/DADA with stable fluorescence property were synthesized based on ligand-exchange method between quantum dots and 1,12-Dodecanediamine(DADA), then were dissolved in aqueous solution of different pH values. The testing results showed that QDs/DADA solution has photoresponse to the pH value, which fluorescence intensities increased and subsequently decreased gradually with the enhangcement of pH values.
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  Application of Poly(2-Acrylamido-2- Methyl Propane Sulfonic Acid) hydrogel in catalyzing esterification reaction

  ;;Shen Xiang ;

  . 2014, 45(15): 10-0.

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  To increase the conversion of esterification and inhibit the harmfulness of conventional catalyst to the environment, this work develops the poly(2-acrylamido-2-methyl propane sulfonic acid) (PAMPS) hydrogel as the alternative of concentrated sulfuric acid and aminosulfonic acid to catalyze esterification. The effect of hydrogel on catalytic efficiency of ethyl acetate synthesis was investigated by the evaluation of swelling behavior of hydrogel. The results indicate that the byproduct (water) in the reaction process can be effectively removed due to the hydration capability of PAMPS hydrogel for water molecules. The catalytic efficiency of hydrogel on the esterification reaches to 89% that is close to the catalytic efficiency of concentrated sulfuric acid, whereas the value is substantially higher than that of aminosulfonic acid. Catalysis activation of PAMPS hydrogel is still retained after the repeated usage of five times.
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  Study on structural and electrical properties of (Mo1/2Sr1/2)4+ doped Bi1/2Na1/2TiO3 based lead-free piezoceramics

  . 2014, 45(15): 11-0.

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  Abstract: Lead-free piezoelectric ceramics, Bi1/2Na1/2Ti1-x (Mo1/2Sr1/2)xO3 (abbreviated as BNT-MS-100x), were fabricated by a conventional solid state reaction method. The effect of the doping of (Mo1/2Sr1/2)4+ on the microstructure and electric properties of the ceramics were investigated. The results showed that all the investigated ceramics have formed a pure perovskite phase with a dense structure. With (Mo1/2Sr1/2)4+doping increases, the Curie temperature increased, the remnant polarization increased first and then decreased, giving its maximum value at x= 0.004, where the Bi1/2Na1/2Ti1-x(Mo1/2Sr1/2)xO3 ceramics exhibited the highest piezoelectric constant of d33=104pC/N, together with the lowest dielectric loss tanδ of 4.11%.
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  Kinetic mechanism of electrodeposition of nickel from citrate solution

  LI Chao qun ;

  . 2014, 45(15): 12-0.

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  Electrochemical behaviour of nickel deposition from sodium citrate solution was investigated by means of electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization test. By analyzing the EIS spectroscopy, the processes of Ni electrodeposition is concluded as follows: in the acidic citrate bath, it involves two consecutive one-electron charge transfers reaction in which Ni(OH)ads acts as an intermediate adsorbed complex. The rate-determining step is the first electron transfer reaction. The low frequency inductive loop is ascribed to the relaxation of the electrode coverage by an adsorbed intermediate Ni(OH)ads. The kinetic equation of electrode reaction can be proposed from the theoretical views and verified by experiment. The results indicate as follows: the Tafel slope of the cathodic process is 0.142V decade-1, the apparent transfer coefficient α is 0.46, the exchange current density is 7.56?10-6A/ cm2, the order of the reaction is 1 with respect to Ni2+. When the electrolyte pH varies between 2~5, no dependence of cathodic rate constants on pH can be found. The coverage of intermediate Ni(OH)ads can not be ignored, the average value of the apparent activation energy of electrochemical reaction is 50.3kJ / mol. The agreement of the kinetic mechanism between theoretical derivation and experimental result is excellent
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  Study on performance of adipic acid/expanded graphite composite phase change materials

  ; ;CHENG Xiao Min;

  . 2014, 45(15): 13-0.

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  Adipic acid as phase change materials, expanded graphite as the heat conduction reinforcement, adipic acid/expanded graphite composite phase change thermal storage material was prepared by mechanical mixing and melted adsorption method. The structure and properties of composite were investigated by FT-IR, DSC, Thermal Constants Analyzer, TG, FE-SEM and Thermal cycling tests. The results show that, adipic acid can be absorbed into the expanded graphite effectively, and exhibits good compatibility with expanded graphite. With the increase of expanded graphite content, the latent has a declining trend, while thermal conductivity is a corresponding increase of composite phase change materials. Adipic acid/8wt.% expanded graphite composite phase change materials melting/solidification enthalpy is 273.66/220.49J/g in melting/freezing process respectively, and thermal conductivity is 2.99W/(m·K). It has a good thermal stability of composite phase change materials.
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  Effects of carbon content and structure on oxidation resistance of silicon oxycarbide fiber

  Yan Jiang;;Jing HE;;

  . 2014, 45(15): 14-0.

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  Silicon oxycarbide fibers were prepared from vinyltrimethoxysilane (VTMS), tetraethoxysilane (TEOS) and phenyltrimethoxysilane (PTMS) by sol-gel method. It was found that the carbon content of the silicon oxycarbide fibers can be adjusted from 21.8wt% to 30.1wt% by change the mole ratio of VTMS, TEOS and PTMS in the precursors. The oxidation resistance of the fibers was impacted by the content and structure of carbon. The oxidation resistance decreased with the increasing content and domain size of the carbon. Silicon oxycarbide fibers prepared with 75%VTMS-25% TEOS showed good oxidation resistance in air at 600?C, because a thin and dense silica film was formed on the surface of the fibers, preventing fibers from further oxidation.
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  Study on the features of interstitial oxygen defects in HfO2 using first-principles calculations

  Guang-Zhen DAI

  . 2014, 45(15): 15-0.

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  The characteristics of interstitial oxygen (IO) in HfO2 have been studied by exceuting first priciple caculation.The formation energies of IOs at different positions in HfO2 have been calculated for the stablest site. The defect energy level, density of states (DOS) and charge trapping energy of this location have been computed. The impact of distance between IOs on the features of HfO2 has been calculated. The results of calculation confirm that IO has amphoteric property for it can capture electron and hole at the same time. The Charges trapped mainly gathered around the interstitial oxygen and the nearest neighbor atom of oxygen. The increasing distance between IOs makes the Coulomb force between two defects by attraction into repulsion, and the repelling force decreases with increasing distance continually, and the acceptor levels introducted by defect significantly increase the number of quantum states, which is advantageous to enhance the hole tunneling current that can be used to realize the rapidly erasion of the storage layer charge.
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  Crystallizing Property of Polyethylene Glycol Hexadecyl Ether with Various Number of Repeat Units

  Xiao-Fen TANG;; ;

  . 2014, 45(15): 16-0.

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  Polymeric phase change material is a new type of energy-storage materials. The crystal structure, thermal property and thermal stability of polyethylene glycol hexadecyl ether (C16En) with various repeat units (n=2, 10 and 20) were characterized using temperature variable fourier transformed infrared spectroscopy (FTIR), temperature variable wide-angle X-ray diffraction (XRD), differential scanning calorimetry (DSC), and thermogravimetric analysis (TG), etc. The number of repeat units has significant effect on the crystallization and phase change properties of C16En. C16En exists in perfect crystal at 0 °C. The crystal structure of C16E10 is the same as that of polyethylene glycol. C16E10 is a typical solid-liquid phase change material. The melting, crystallizing temperature and enthalpy of C16E10 are 33.7 °C, 15.0 °C and 148 J/g, respectively. The thermal stability of C16E10 is 296 °C, which is higher than those of n-hexadecane and 1-hexadecanol. C16E10 is a promising phase change materials.
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  Effect of Modification on Property of MCC/PA6 Composites

  ;;WU Yucheng

  . 2014, 45(15): 17-0.

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  Microcrystalline cellulose was modified by 2, 4-Diisocyanatotoluene (TDI), and the results showed that TDI was successfully grafted to the surface of MCC through scanning electron microscopy (SEM) and Fourier Transform Infrared Spectrometer (FTIR Spectrometer) analysis. The MCC/PA6 composites and TMCC/PA6 composites were prepared via in-situ polymerization of caprolactam(CL) after dispersion MCC and MCC modified (TMCC) in caprolactam, and the effect of MCC modified on MCC/PA6 composites was investigated. The results showed that the conversion rate of CL in MCC/PA6 composites decreased as the content of the MCC increased, but the conversion rate of CL in TMCC/PA6 composites did not make any difference with increasing of the TMCC. In addition, the conversion rate of CL in MCC/PA6 composites was higher than that in MCC/PA6 composites. Compared with pure PA6, the molecular weight of PA6 in MCC/PA6 composites were affected more than TMCC/PA6 composites, and the molecular weight of PA6 in TMCC/PA6 composites was higher than that in MCC/PA6 composites, and it was almost the same as the pure PA6. The shear viscosity of the composites and pure PA6 were tested at 250 ℃, and the results presented that the shear viscosities of composites were higher than those of pure PA6, and the shear viscosity of MCC/PA6 composites was the highest.
工艺 技术
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  Experimental investigation of the effect of mechanical vibration on the filling ability of A356 aluminum alloy

  Jian-Hua ZHAO

  . 2014, 45(15): 18-0.

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  Abstract：Mechanical vibration was applied to A356 alloy filling process, the filling length of the alloy was measured under different vibration frequency, the mathemati-cal expression between the filling length and vibration frequency was set up by poly-nomial regression to explore the effect mechanism of mechanical vibration on alloy filling ability. The result indicates that in filling process of the A356 alloy, the flow resistance is reduced and grains are refined to improve the filling ability of liquid metal while the heat transfer coefficient is increased to make the filling ability of liq-uid metal reduce. So the effect of mechanical vibration on the filling ability is not monotonic, and it has a vibration frequency that make the A356 alloy filling ability reaches a maximum value among 20Hz ~ 50Hz, and f=39.05Hz，LMax=823.89mm is maxima through regression analysis.
研究 开发
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  Phase diagram prediction of the LiNO3-NaNO3-KNO3 ternary system and its thermodynamic performance

  ;;;

  . 2014, 45(15): 19-0.

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  The symmetric Kohler model was applied to predicted phase diagram of the LiNO3-NaNO3-KNO3 ternary system, in which one ternary eutectic point (its molar fractions composition: XLiNO3=0.388, XNaNO3=0.102, XKNO3=0.510) with low melting temperature was found to be 395.50 K. The DSC and TGA curves of the predicted eutectic point were measured and the results showed that the melting temperature is 397.32 K and the thermal stability temperature is 868.62 K, and the predicted molten salts mixture is expected to be used in concentrating solar power and nuclear energy power plants.
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  Effect of hard and soft monomers contents on acrylate on synthesis and Surface Sizing Performance of Polyurethane-acrylate Emulsion

  . 2014, 45(15): 20-0.

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  The waterborne polyurethane-acrylate emulsion was prepared by in-situ surfactant-free polymerization. The effect of soft and hard monomers ratio on the particle size, viscosity, and gel content, water absorption, mechanical properties of films were studied. Also the impact of WPUA on paper enhancement. The result shows that the average panicle size increased with the increase of w(MMA) , while the viscosity decreases. And for WPUA films, gel rate increased with the increase of w(MMA), and water absorption decreased first and then increased. WPUA film owns excellent mechanical properties when w(MMA)=14.37 %；With 1 % WPUA emulsion addition，the paper sizing value reach 37.47 s, wet strength reach 31.61 %. Folding endurance reach 56 times when w(MMA)=8.64 %.
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  Mixed monolayers of Poly(ε-caprolactone) grafting O-Sulfonated Chitosan with Cholesterol

  ; ;

  . 2014, 45(15): 22-0.

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  O-sulfonated chitosan-graft-poly(ε-caprolactone)(HSCS-g-PCL) was synthesiz- ed and the structure of it was characterized by FTIR，1H NMR and EA. The properties of mixed monolayers of HSCS-g-PCL and cholesterol were studied. Experimental results indicated that when cholesterol was added, the π-A isotherms of the HSCS-g-PCL monolayer turned from expand type into condensation type and had obvious LE-LC phase transition. As the cholesterol molar ratio increased, collapse pressure and the limiting molecular area of mixed monolayers decreased, meanwhile maximum compression modulus increased. The value of ΔGexc changed from an repulsive interaction to an attractive interaction between HSCS-g-PCL and cholesterol with a critical point when cholesterol molar ration was 0.6. When molar ratio of cholesterol is 0.8, ΔGexc of mixed monolayers was minimum and the mixed monolayer was the most stable.
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  The fabrication and micro tribological properties of multi-layer graphene deposited by magnetron sputtering method

  chen leiming

  . 2014, 45(15): 23-0.

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  Large-scale and multi-layer graphene were fabricated by magnetron sputtering method on Cu substrates. The structure and morphology were characterized by SEM, AFM and Raman spectrum et al. The result revealed that there are many-layer structures contained in these grapheme films. The micro tribological properties were characterized by AFM and they are tightly relating with layer numbers of graphene.
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  Simulation Reconstruction Analysis of Gradient Refractive Index for Functionally Gradient Materials Based on Filtered Back Projection

  Hai-Peng LI;

  . 2014, 45(15): 24-0.

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  As parameters of functionally gradient materials are hard to represent, reconstruction method based on compressive sensing digital holographic tomography is proposed. In order to improve the reconstructed resolution of refractive index, this paper focuses on simulation analysis of the tomographic reconstruction effect and resolution of functionally gradient materials' gradient refractive index. Functional materials with radical or axial varient refractive index are analyzed, and reconstruction results are compared. In the same simulation condition, the reconstruction error are all 1%. The resolution of reconstruction is also analyzed in simulation situation. From the simulation result, when the number of projection is 90, radial reconstruction error is lower than axial reconstruction. In addition, the gradient intervals can be identified from the reconstructed gradient trend of refractive index when the original gradient interval is larger than 0.003.
综述 进展
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  Developments of SiC Nanofibers Fabricated by Electrospinning

  . 2014, 45(15): 25-0.

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  Silicon carbide (SiC) nano?ber posseses many excellent properties, such as low thermal-expansion coef?cient, high specific surface areas, high mechanical strength, superior thermal stability and high thermal conductivity. Electrospinning technique for preparing SiC nonfibers has been considered to be one of the most straightforward and versatile techniques, and SiC nanofibers fabricated by electrospinning have been successfully applied in many ?elds, such as mechanics, electrics, optics, and calorifics, et al. This paper presents a comprehensive review on the fabrication of SiC nanofibers and influencing factors after briefly introducing the basic principles and apparatus of electrospinning. Then the secondary structures of SiC nanofibers are briefly presented. At last, the applications and future trends are presented for SiC nanofibers in this paper.
工艺 技术
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  Effect of Pretreatment on Bamboo Strip and Bamboo-wood Hybrid Scrimber Property

  Wei-Min CHEN

  . 2014, 45(15): 26-0.

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  The physical and chemical property of bamboo strip treated by carbonization and microwave was researched by the analysis methods of contact angle/interfacial tension meter, ESR，XRD and FT-IR. The physical and mechanical properties of bamboo-wood hybrid scrimber prepared by pretreated bamboo strips was researched. The research results showed that the contact angle of bamboo strip surface treated by carbonization was higher than that with no pretreatment, while the contact angle of bamboo strip surface treated by microwave was lower than that with no pretreatment. The free radicals concentration of bamboo strip treated by carbonization was decreased than that with no pretreatment, while the free radicals concentration of bamboo strip treated by microwave was increased. The relative crystallinity of cellulose in bamboo strip were both increased by carbonization and microwave pretreatment, the increasing extent of relative crystallinity treated by carbonization was larger than that treated by microwave. The number of hydroxyl in bamboo strip treated by carbonization was decreased, while the number of hydroxyl in bamboo strip treated by microwave was increased. The MOR of bamboo-wood hybrid crimber was decreased by the two pretreatment, the change of MOE is not obviously, the IB and TS of bamboo-wood hybrid crimber pretreated by carbonization was decreased, while the IB and TS of bamboo-wood hybrid crimber pretreated by microwave was increased.
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  Preparation and thermoelectric properties of bismuth telluride-carbon fiber reinforced cement composites

  Qiang Xia

  . 2014, 45(15): 27-0.

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  Bismuth telluride-carbon fiber reinforced cement composites were prepared in two ways, bismuth telluride mixed with cement and as coating. Influences of the dosage of Bi2Te3 and the adding method on the thermoelectric properties of cement composites were studied, and a thermoelectric model was proposed for bismuth telluride as coating in cement composites. The results indicate that electric polarization effects were observed in bismuth telluride mixed cement composites and electric polarization weakened with the prolonging of curing time. The addition of Bi2Te3 could greatly enhance the thermoelectric properties of cement composites and the way that Bi2Te3 was used as coating showed better thermoelectric property. The Seebeck coefficients of Bi2Te3 coating and carbon fiber reinforced cement lamina were calculated based on the thermoelectric model indicating that Bi2Te3 coating is of higher Seebeck coefficient, enhancing the thermoelectric properties of whole cement composites.
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  Influences of buried strain on the growth of Ge quantum dots prepared by ion beam sputtering

  ;Yu YANG

  . 2014, 45(15): 30-0.

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  Abstract: Double-layers Ge/Si quantum dot samples were grown on Si(100) substrate by ion beam sputtering system. The influence of buried strain on the growth of islands on the upper layer was studied by varying the thickness of Si spacer-layer and Ge deposition. When the thickness of spacer-layer is thin, the results show that a reduction of wetting-layer thickness of islands on the upper layer. In addition, with increasing the thickness of Ge deposition, the growth of islands on the second layer is modulated. Increasing the thickness of spacer-layer, the growth of islands on the second layer follows the buried dots. The change of growth mode is explained by the non-uniform strain field induced by the buried islands and passing through the spacer-layer.
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  Preparation and characterization of collagen re-assembled fibers

  Xiang-Yi WEI;Bi SHI

  . 2014, 45(15): 31-0.

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  Abstract：Collagen re-assembled fibers were prepared from type I collagen molecules via salting out – acetone dehydration – glutaraldehyde crosslinking. Then the material was characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC) and specific surface area analyzer, to obtain its morphology, thermal stability and specific surface area. The results showed that the collagen re-assembled fibers presented a fluffy fibrous appearance with faint yellow color. SEM images revealed that the collagen re-assembled fibers were composed of interwoven nano fibrils (30-150nm in diameter), at the micro-scale. The specific surface area of the material was 26 m2/g, which was more than that of natural and modified collagen fibers. Collagen molecules in the material still kept a natural triple helix structure. The thermal denaturation temperature of the material was 85℃. The preparation of collagen re-assembled fibers provides a prospect for further utilization of collagen resource, such as adsorption material, catalyst supported material and biomaterial.