15 September 2015, Volume 46 Issue 17
    

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    研究 开发
  • ;; ;
    . 2015, 46(17): 1-0.
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    The application of Fenton reaction is restricted to a narrow pH range (2~3.5), which has long been a technological bottleneck. Therefore, the development of a pH-tolerant Fenton-like catalyst is an active and challenging research front in the field of environmental catalysis. In this work, we evaluated the pH-tolerant performance of the novel Fenton-like catalytic fibers (QuFe@ACFs) based on activated carbon fibers (ACFs) coupled with 8-hydroxyquinoline ferric (QuFe) by a simple impregnation method. The UV-vis spectroscopy measurements showed that the reactive brilliant red M-3BE (RR M-3BE) was completely degraded in 32 min. Probe compound O-phenylenediamine combined with electron paramagnetic resonance (EPR) spectroscopy and UV-Vis spectroscopy were employed to demonstrate the catalytic stability of QuFe@ACFs, and the experimental results showed that QuFe@ACFs exhibited excellent catalytic ability and recycle utilization performance across a wide pH range from 3 to 9, brought remarkable pH-tolerant performance. To sum up, the QuFe@ACFs prepared by an extremely simple impregnation method, breaks the technological bottleneck for Fenton treatment, providing new ideas for preparing novel pH-tolerant Fenton-like catalysts with excellent catalytic activity.
  • LIANG SHU
    . 2015, 46(17): 2-0.
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    A dynamic model of Galfenol actuator is developed by using a linear piezomagnetic equation and the Euler- Bernoulli equation. The magnitude and the phase of the excitation field demonstrate the diffusion effect in the magnetic circuit due to the existence of the dynamic eddy current loss. The model prediction of the flexible beam can be directly affected by the influence of the eddy current loss. A genetic algorithm is proposed to identify the parameters of the model, for which the persistent excitation condition is not needed. The piezo-coefficient and the damping constant are identified at different dynamic frequencies. Simulation results show that the proposed method achieves good convergence performance that the optimal model parameters can be found after several iterations. Experimental results show that the variations of the model parameters are small when the exciting frequency is low (less than 220 Hz). Larger variations happen when higher frequencies are applied. The changes of the model parameters according to the eddy current loss at different frequencies can be effectively described by the method, which can be used for design and control of the Galfenol flexible structure.
  • 综述 进展
  • Wen-Xi YU;
    . 2015, 46(17): 3-0.
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    Edible/degradable films carrying antimicrobial agents are attracting increasing attention from scientists. It can provide active protection to package products by continually releasing antimicrobial agents onto food surface to prevent the product deterioration, extend the shelf life and maintain the safety and sensory quality of several food products. This paper illustrated the application and development prospects of edible/degradable films carrying antimicrobial through three aspects: material source, types of antimicrobial agents and the release kinetics of antimicrobial agents.
  • 研究 开发
  • ;
    . 2015, 46(17): 4-0.
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    The effects of different conductive additives on cathode performance were investigated employing metal powders of copper and silver and carbon materials such as activated carbon, acetylene black, carbon nano tubes (CNTs ) to high potential Cu3V2O8 cathode for low-temperature/high-voltage thermal battery. The results show that all these conductive additives can improve the discharge performance of the Cu3V2O8 cathode. Furthermore, carbon materials are more suitable used as conductive additives for low-temperature/high-voltage thermal battery cathode than metal powders. The optimal content of activated carbon, acetylene black and CNTs in the cathode is 4%, 3% and 3% respectively while CNTs has the best cathode performance improvement of all. The content of electrolyte has a small effect on cathode performance with the propriate composition of 30%.
  • . 2015, 46(17): 5-0.
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    The vertical upward directional growth process of SCN-5%ETH (Succinonitrile-%Ethanol, % is as mass fraction) model alloy is experimentally examined with real-time observation devices and directional solidification system. The experimental observations are compared with horizontal directional growth for cell structure, dendritic structure and dendritic spacings of SCN-5%ETH model alloy. Cell tips become small and the radius of cell tip decreases because of the solute convection within the intercellular induced by upward growth when comparing with horizontal directional growth. The secondary dendrite arms grow slowly during upward growth comparing with horizontal directional growth. The primary dendrite arms spacing and the lengths of secondary dendrite arms decrease more and more slowly with the increase of growth rates during upward growth, but the secondary dendrite arms spacing has a little increase during upward growth comparing with horizontal directional growth.
  • Wu Wen Hui; ;;
    . 2015, 46(17): 6-0.
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    Abstract: Femtosecond laser ablation of the surface on GaAs solar cell has been investigated. The research results indicated that femtosecond laser irradiation can cause a certain degree of damage to the GaAs solar cell surface at a certain laser fluence, and the injury degree increase with the increase of laser fluence or the decrease of scanning speed. The ablated surface were characterized by optical microscopy, found that the ablation area expanding with increasing laser fluences, which is due to the Gauss distribution of femtosecond laser energy. The abaltion threshold of the TiO2/SiO2 films of GaAs solar cell surface was obtained from the linear fit of the dependence of the square diameter of the ablated area with the natural logarithm of the laser pulse energy, the resulting threshold of the laser fluence is about 0.35 J/cm2, and test result is about 0.27J/cm2. The certain numerical difference may be due to the simplified theoretical calculation of laser spot pattern and the uncertainty factors of material.
  • Liang LV;
    . 2015, 46(17): 7-0.
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    Abstract: 8 at.% yttria-stabilized zirconia (8YSZ) nanocrystalline powder prepared by sol-gel method was sintered at 1200℃. XRD spectra indicate that the sintered sample maintain a single cubic phase structure, while the grain size and the crystallinity increases. Raman spectra reveal that the as-prepared sample is a single cubic phase structure, while the sintered sample composes of cubic phase and monoclinic phase, and the content of monoclinic phase is less than that of the cubic phase. The density of the sample obtained by SPS method is 92.7%, and the vickers hardness is 1551 Mpa .
  • ;;Cai-Xia LIU;
    . 2015, 46(17): 8-0.
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    The conductive composite material is prepared by using carbon black (CB3100) as conductive phase and silicon rubber as matrix. Effect of nano-SiO2 on static and dynamic characteristics of pressure-sensitive conductive rubber was studied. The results of static characteristics revealed that nano-SiO2 doped in the proper scale had good modification to conductive rubber. It enhanced the conductivity of conductive rubber, and shortened the relaxation time of the resistance. The addition of SiO2 improved linearity of the pressure-resistance curve, and advanced the temperature stability of conductive rubber. The results of dynamic characteristics showed that the addition of SiO2 made the resistance of conductive rubber under the step-force went to stability faster, but had no significant impact on the response time and the frequency response. Moreover, addition of SiO2 also had negative impact, such as increased the peak time of the step response time.
  • ; ;;;;
    . 2015, 46(17): 9-0.
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    A phase-pure and high-efficiency double peaks phosphor, Eu2+-Mn2+ co-doped SrMgAl10O17 (SAM) was prepared through sol-gel combustion. The crystal structure and luminescent properties of the SAM were investigated in proper ways. The XRD results show that the prepared SAM: Eu2+, Mn2+ phosphors is well-crystallized, and the SEM results indicate that these powders are consisted of well-dispersed uniform particles (about 1 μm in length). With the increase of Mn2+ concentration, the emission spectrum appears double peaks, respectively for 465 nm and 515 nm. While the Mn2+ doping is at 11%, the energy transfer of Eu2+-Mn2+ reaches saturation. The energy transfer mechanism was illuminated to be dipole–quadrupole interaction with the help of Dexter energy transfer theory, critical distance and the energy transfer mechanism were also calculated. Moreover, the 11% additional Mn2+-doped sample had the higher thermal stability than that of the sample without additional Mn2+.
  • Jun WANG;Xing-Feng DING;;;
    . 2015, 46(17): 10-0.
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    Mn-doped MgFe2O4 spinel infrared radiation materials were prepared by solid state reaction.The effect of Mn doping on the microstructure and infrared radiation properties of MgFe2O4 were investigated by XRD、FT-IR、SEM and infrared emissivity. The results show that a small amount of Mn doping can significantly improve the sintering performance of materials and increase the infrared radiation properties. In the series spinel oxides, Mg0.8Mn0.2Fe2O4 shows the best performance with the infrared emissivity of 0.776 in the bands of 3~5μm and 0.936 in the bands of 8~12μm.
  • Li-Qiang WANG
    . 2015, 46(17): 11-0.
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    Abstract:Polylactic acid is a biodegradable packaging material; it was studying the effect that adding β-cyclodextrin-trans-2-hexenal microcapsules on performance, including mechanical properties, optical properties, and morphological changes. The result shows that, with increasing proportion of added, the tensile properties of films, elongation at break, and the transmittance rate is gradually reduced, while the L * value increased, and it was observed by scanning electron microscopy (SEM) that adding microcapsules caused surface pores, irregular phenomenon.
  • 综述 进展
  • . 2015, 46(17): 12-0.
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    Tungsten bronzes AxWO3(0
  • 研究 开发
  • Qing-Gong SONG ;;;
    . 2015, 46(17): 13-0.
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    γ-TiAl based alloys are lightweight and withstanding high temperature materials with a broad application areas. The γ-TiAl based alloys systems doped with Nb or Cr mono-substituting, Nb and Cr co- substituting are investigated by using first-principles method base on the density functional theory (DFT). The geometric structures, average formation energies of atom, populations, charges and elastic constants are calculated and analyzed with this method. The obtained formation energies of atom show that Nb atoms tend to substitute Ti atoms, while Cr atoms have no evident tendency. The four Nb and Cr co-doping systems possess negative formation energies indicating the stabilities of their structures and the advantages for experiment preparation. Through the calculations and analysis about axis ratios of unit cell, elastic modulus ratios and populations, the important effects of Nb and Cr co-doping for improving the ductility are presented. The paper forecasts that Ti7NbAl7Cr and Ti7CrAl7Nb systems possess good composite effect for the improvement of ductility, and the former is better than the latter. These results suggest the direction of experiment investigation.
  • . 2015, 46(17): 14-0.
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    The powders of rare earth element M (Eu, Nd, Y) doped CuAlO2 were synthesized by inorganic sol-gel method. Formation process of doped CuAlO2, phase structure, optical properties were studied by DSC-TGA, X-ray diffraction and UV-Vis spectrophotometer. The results showed that the rare earth doped CuAlO2 phase can be formed at 950℃. After treated at 1100℃ for 4h, phase composition of the powders is dependent on doping content. The 0.5% doped powder is composed of main phase CuAlO2 and a small amount of CuO phase. When the doping content is greater than or equal to 1%, the doped powder is composed of main phase CuAlO2, a small amount of CuO and MAlO3 phase. Diffraction peak intensity of YAlO3 phase is the lowest among EuAlO3, NdAlO3 and YAlO3 phase. Higher treatment temperature is favorable to solution into the CuAlO2 lattice of the doping elements and formation of CuAl1-χMχO2 phase. CuAlO2 decomposes at 1150℃. When the doping content of Eu was less-then 1%, The optical band gap increased, the resistivity decreased and the photoelectric performance improvemented.
  • ;
    . 2015, 46(17): 15-0.
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    N-V-codoped nanosized TiO2 powders were prepared by the sol-gel method with tetrabutyl titanate as Ti resource, hexamethylene tetramine as nitrogen resource and ammonium metavanadate as vanadium resource.N-V-TiO2 powders were characterized by XRD, UV-Vis, BET and XPS. The photocatalytic decomposition property of N-V-TiO2 to formaldehyde under visible light was investigated. The results show that the N-V-TiO2 of calcination temperature at 500, the N-doped amount of 28%, the V-doped amount of 1% has the anatase and rutile mix structure, large specific surface area and strong visible light absorption. The degradation efficiency of formaldehyde is up to 91.6%, which is significantly higher than that of TiO2,N-TiO2 and V-TiO2 respectively. The degradation efficiency of formaldehyde decreased with the increase of its concentration by N-V-TiO2 and the photocatalytic reaction was first order and included adsorption and photocatalytic oxidation which was the rate-controlling step. The degradation efficiency after 5 times reuse by N-V-TiO2 was still higher than that of N-TiO2 and V-TiO2.
  • Xue-feng LU ;;
    . 2015, 46(17): 16-0.
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    Carbon fiber preform was designed to three layers with variable density along the thickness. Then C /C composites were obtained by chemical vapor infiltration (CVI). The influence of preform structure on the oxidation behavior of C/C composites was studied by isothermal oxidation test. The results show that the oxidation of C/C composites with variable density preform has the same modes to that of traditional C/C composites, kinetic rate controlled mode and the diffusion rate controlled mode. The variable density preform has little or no influence on the kinetic rate controlled mode, but hinders the oxygen diffusion due to the pore structural change. Therefore, the high temperature oxidation resistance of C/C composites was improved.
  • koubao FENG;wangluming
    . 2015, 46(17): 17-0.
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    On the basis of the research on the modification on magnesium oxychloride cement (MOC) with phosphoric acid, fly ash and calcium stearate respectively, then phosphoric acid, fly ash and calcium stearate or phosphoric acid, fly ash and styrene-acrylic emulsion were adopted to improve the water resistance of MOC. The results show that, while adding 1wt% phosphoric acid, 20wt% fly ash and 1wt% calcium stearate or 1wt% styrene-acrylic emulsion to the cement, the stability of 5 . 1 . 8 main phase in water ,the density and water resistance of the cement were improved effectively, among them, phosphoric acid, fly ash and styrene-acrylic emulsion as compound modifiers are the best.3 days’ and 7 days’ compressive strength of optimal modified specimen can reach 63.4、75.1MPa respectively, softening coefficient were up to 0.9,after a 7 days’ immersion test, compressive strength still can maintain 68.1MPa, improving 60.2% compared with blank specimen,the compound modification effect is remarkable.
  • . 2015, 46(17): 18-0.
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    A novel “A-D-A” organic ligand L (A: terpyridine; D: fluorenyl) and its palladium complex (L2Pd)n were synthesized and their structures were characterized by 1H NMR and IR spectra. A solid electrochromic device (ECD) with fluorenyl-terpyridine-palladium complex (L2Pd)n. as active layer was prepared in the structure of “ITO/(L2Pd)n /PE:LiClO4-PMMA-PC/ITO”. Color of this device (ECD) was reversiblely changed from yellow to orange under the change of voltage from 0 to 2.4 V, which can maintain more than one hour without encapsulation.
  • 工艺 技术
  • ;
    . 2015, 46(17): 19-0.
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    Cadmium sulfide (CdS) target was developed by dry-pressing molding and vacuum sintering with CdS raw material and CdCl2 as fusion. Raw material property and the influence of sintering temperature and CdCl2 content on relative density, linear shrinking, apparent porosity and resistivity of CdS target were studied in this paper. The density of target was measured using Archimedes method, the resistivity was measured by SX1934 four probe instruments, the phase structure of target was analyzed by X-ray diffractometer with a monochromated Cu Kα X-ray source, and the fracture morphology was observed by SEM photograph. Specifications were as following: the phase structure was hexagonal Wurtzite, the density was 4.55g?cm-3, the pore ratio was 4.59%, the resistivity was 89.2Ω?cm, the crystal size was homogeneous (3-8μm), these properties can meet sputter coating requirements.
  • ;;
    . 2015, 46(17): 20-0.
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    Isothermal compression tests of 2099 Al-Cu-Li alloy were performed on a Gleeble-1500 system in the temperature range between 350℃ and 500℃ at strain rates between 0.001 s-1 and 1 s-1. The flow behavior was described by a hyperbolic sine constitutive equation and the microstructures of samples were observed by optical microscopy (OM). The results showed that peak stress levels decreased at higher deformation temperatures and lower strain rates. The results were represented by the Zener–Hollomon parameter in an exponential equation with an activation energy for hot deformation of 325.48 KJ/mol.
  • 研究 开发
  • Xiao-Ying LIN;;;
    . 2015, 46(17): 21-0.
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    Porous cocoanut activated carbon was modified using tree chemical methods: Tetraethylene pentamine (TEPA) modified directly(AC)?firstly oxidized by HNO3 solution (10%) for 4 h at 353K then TEPA modified(HNO3+TEPA)and firstly alkalified by KOH solution (5mol/L)for 4 h at 353K then TEPA modified(KOH+TEPA). The results show that KOH reduction on AC improved the effect of the modification, HNO3 oxidation on AC has no significant effect on modification .The CO2 adsorption capacity of OH-TEPA-AC measured using a thermogravimetric analyzer (TGA) in simulated flue gas conditions (10 vol.% CO2,90.vol.%.N2) is about 1.182 mmol/g at 303 K , the Dynamic adsorption capacity is between 1.192~1.215mmol/g and 0.97-1.152mmol/g with or without the presence of water during ten cycles of adsorption/desorption。Dynamics analysis shows that the average isosteric heat of adsorption is about -52KJ/mol, so OH-TEPA-AC is likely to be satisfactory in practical applications of capturing CO2.
  • 工艺 技术
  • Li-Ting LU
    . 2015, 46(17): 22-0.
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    The nanofibers loaded with slightly soluble drug—Ibuprofen(IB) as solid dispersion were prepared by electrospinning technology with poly ethylene oxide (PEO) and corn starch (ST) as the carrier.A three-dimensional continuous network structure of the nanofibers was observed by scanning electronic microscopy. The hydrogen bonding interactions among IB,PEO and ST were demonstrated by infrared spectroscopy. The results of X-ray diffraction suggested that IB was highly distributed in the nanofibers at an amorphous status or a molecular state when the drug content was small.There will appear some crystal precipitation when the drug content increases. The results of in vitro dissolution test showed that when the drug content of nanofiber increased,the release time of IB will longer.When the drug content was constant, along the ST content increase,the release rate will increase and the release time will decrease.
  • Zhi-Qiang Cui;;;;;Yu-Qiao ZENG
    . 2015, 46(17): 23-0.
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    The determination of the nitrate concentration is one of the key issues for the conservation and improvement of the ecological environment. This work reports the formation of copper nanoclusters which has high catalytic activity towards the electrochemical reduction of the nitrate. The results show that the depositing time plays an import role on the structure and catalytic performance of the copper nanoclusters. 30 s of deposition leads to the strongest current signal and a good linear relationshipbetween the current density and the nitrate concentration in a wide nitrate concentration range from 0.5 to 5.0 mmol/L.
  • . 2015, 46(17): 24-0.
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    Abstract: The nano magnetic composite microspheres(Fe3O4/PS-EDTA)were prepared by polymerization and substitution reaction.First,the Fe3O4/PS particles were prepared through polymerization of styrene(st) in the surface of Fe3O4.Second,hydrogen atoms of Fe3O4/PS were substituted in proper order by chlorine、ehylenediamine and acetic acid.The synthesized Fe3O4/PS-EDTA were characterized by Scanning electron microscopy (SEM),X ray diffraction, thermogravimetric (TGA) analysis,Fu Liye transform infrared (FT-IR) spectrometer and ultraviolet spectrophotometer.Results show that EDTA were effectively connected with chemical bond to the surface of nano-magnetic Fe3O4/PS with uniform particle size.The adsorption dynamic process fit the Langmuir isotherms well with a maximum adsorption capacity of 98.59 mg/g for Cu(II) and the adsorption kinetics followed the mechanism of the pseudo-second order equation.
  • ;
    . 2015, 46(17): 25-0.
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    Abstract: The β-In2S3 thin films with excellent properties were prepared by magnetron sputtering In films and sulfurizing heat treatment process. Qualities of thin films were analyzed by used XRD, Raman spectroscopy and UV-Vis spectroscopy; The results demonstrate that sputtering power have great influence on the crystallization properties of thin film, the optimization sputtering power is 100-140W.In addition, heat treatment temperature has also great influence on the quality of the thin film, more appropriate heat treatment temperature is 450℃.The over high heat treatment temperature is easy to cause defects and produce In5S4 impurity phase in the film. In contrast, the sputtering gas pressure effect on the film quality is small, the sputtering gas pressure can be selected in the 04-0.6Pa. Optical and electrical performance test results show that obtaining the β-In2S3 thin films have better quality and high spectral transmittance, which belongs to n type semiconductor, can be used buffer layer for solar cells.
  • rui-jie WANG
    . 2015, 46(17): 26-0.
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    The compound super absorbent resin was synthesized by starch, bentonite, acrylic acid and acrylamide, using microwave irradiation. Some key factors affecting the solution absorbency of the polymer such as the amount of bentonite, acrylamide, initiator and cross-linking agent have been discussed. The results showed that the optimal reaction conditions of cross-linking agent, initiator, neutralization degree, bentonite, phosphate starch are 0.045%, 0.32%, 70%, 10%, 3% when the weight ratio of acrylic acid and acrylamide was 2:1, the microwave power was 800W, the radiation time was 15min. Under the conditions, the pure water absorption rate of super absorbent resin was up to 796g/g. when the weight ratio of acrylic acid and acrylamide was 1:1, the absorption rate of 0.9% NaCl was 95g/g.
  • ;Bing LIANG ;;
    . 2015, 46(17): 27-0.
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    Abstract A phosphorus-containing flame retardant bis (4-hydroxyphenyl) phenyl phosphine oxide (BHPPO) was synthesized by the reaction of phenyl phosphonic dichloride(PPD) and hydroquinone(HQ). The chemical structure of the obtained compound was identified by FT-IR, 1H NMR, 13CNMR and ESI-MS. The optimum reaction conditions were determined as follows: in nitrogen atmosphere, the mole ratio of phenyl phosphonic dichloride and hydroquinone is 1:2.4, 40mL xylene as solvent, reaction temperature is 130℃, the reaction time is 10 hours, yield is 91.73%. And the thermal stability of BHPPO was tested by MP and TG.
  • ;
    . 2015, 46(17): 28-0.
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  • . 2015, 46(17): 29-0.
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    Graphite films were prepared from DuPon polyimide films with different thicknesses by carbonization and graphitization treatments at a certain press. The micro-structural evolution of PI films during the process of high-temperature treatments was characterized by polarized light microscope, scanning electron microscope, X-ray diffraction and Raman spectrum. The results show that the PI graphite films (with a thickness of 50μm for raw films) possess a three-dimensional structure of graphite layers with preferred orientation and prefect graphite crystals after graphitization at 3000oC. The corresponding interlayer spacing and stacking height of (002) crystal plane of the PI graphite film are 0.336nm and 65.94nm, respectively. The degree of graphitization of the PI graphite film is as high as 93%, and the electrical resistivity and thermal conductivity of the PI graphite films at room temperature in the main plane direction are measured to be 0.48μ??m and 994W/m?K, respectively. The higher heat-treated temperature, the more easily transformation from the turbostratic carbon to ordered graphite, resulting in the better growth and crystallization of graphite microcrystals, and the more orientation of graphite layers. However, the microcrystals in the thick PI graphite films grow and crystallize difficultly, and their preferred orientation of carbon layers is very low.
  • ;De-yuan Zhan
    . 2015, 46(17): 30-0.
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    According to the mechanism of metal carbonyl solution direct thermal decomposition to metal atom and CO at high temperatures and using the Chemical vapor deposition(CVD) method, this paper showed a way to prepare the flaky NiFe-Diatomite composite particles. By evaporating the mixture of Ni(CO)4 and Fe(CO)5, in the N2 atmosphere, the deposition of NiFe alloy happened on the pre-heat diatomite earth surface. The scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDS), X-ray diffraction (XRD), and vibrant sample magnetometer (VSM) were used to make clear their morphology microstructure, chemical composition, crystal structure, and magnetostatic characteristic.The result showed that the flaky NiFe-Diatomite composite particles were prepared successfully, which better maintained the microporous structure of diatomite. Moreover, the soft magnetic manganese composite was fabricated with the saturation magnetization Ms at 56 emu/g and coercive force Hc at 10Oe.
  • ;Zhong-Fei ZHU ;;
    . 2015, 46(17): 31-0.
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    The effect of cooling methods on the microstructure, thermal stability, optical and mechanical properties of 99.75Ge23Se67Sb10-0.25RbI glass were studied by DSC, XRD, SEM, FT-IR and Vickers hardness test in this study. The results indicated that, for air cooled glass, the infrared transmittance at wavelength of 8-12 μm is above 70%, which is higher than that of water cooled glass(64%). However, due to the slow cooling rate of air cooled, the solid solubility of hydrogen in selenium increases, thus the absorption of impurities is also stronger than that of water cooled glass. For the thermal-treatment samples, the diffraction peaks of Sb2Se3 and GeSe2 crystals can be found at 280℃/20h for the glass cooled by air, but at 300℃/20h for the glass cooled by water. After thermal treatment, the fracture toughness of water cooled glass can reach to 0.414 Mpa*m1/2, increased 26% compared with that without thermal treatment, and it is higher than the maximum KIC(0.368 Mpa*m1/2) of air cooled glass. Consequently, water cooled chalcogenide glass has a higher stability and a better fracture toughness, thus it is more suitable for preparing micro-crystallizing chalcogenide glass.
  • Chaoyi Chen;Feng Yang;Huilin Chen;Jing LIU
    . 2015, 46(17): 32-0.
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    In order to solve the problems existing in the preparation process of La-Mg-Ni alloy, such as oxidation and volatilization, the La-Mg master alloy was prepared by a smelting method with protection by molten salt and used as raw material to sintering synthesis La2MgNi9 alloys. The sintering process was assisted by a strong magnetic field. The XRD results indicates that the single phase for all alloys is PuNi3 type (La, Mg)Ni3. The pressure–composition isotherm (PCT) results show that the alloys prepared under 1 T magnetic field has the maximal hydriding capacity (1.490 wt.%). The alloy shows excellent hydriding/dehydriding kinetics properies. The desorption heat behavior of all alloys have no significant change with the change of magnetic field intensity.
  • YANG Wen-fang
    . 2015, 46(17): 33-0.
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    Abstract: A microcapsule with intelligent photochromic and energy storage temperature adjustment function has been prepared with melamine-formaldehyde as wall material via an in situ polymerization method, and the photosensitive color material which has been dissolved in phase change materials of fatty acid ester was chosen as the core material. DSC, TGA, SEM, particle size analysis and color measurement were used to characterize the prepared microcapsules. The results indicate that the microcapsules had good formation with smooth and compact spherical surfaces, and their particle size was centralized in 3-4μm. Moreover, the microcapsules exhibited excellent performance on photochromic energy storage and temperature adjustment. The rise and cooling phase transition temperature were found to be 27.0℃ and 20.2℃, and the molten phase transition enthalpy and solidification phase change enthalpy were calculated to be 68.1J/g and 86.2J/g, respectively. Key words: photochromic; Phase change energy storag;situ polymerization;melamine-formaldehyde;microcapsules.