The relations among composition, structure, chemical bond and property of composites of TiC/Al2O3 ceramic and doped series are studied by using density function and discrete variation method (DFT-DVM). There are stron...
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The relations among composition, structure, chemical bond and property of composites of TiC/Al2O3 ceramic and doped series are studied by using density function and discrete variation method (DFT-DVM). There are strong ionic and covalent interactions between two phases of TiC/Al2O3, the interaction becomes stronger when doping Ni into TiC/Al2O3, and the interaction of doping Mo into TiC/Al2O3 is stronger than that of doping Ni. The results are consistent with the experiment that doping can improve the combination of the phases in TiC/Al2O3, enhance hardness and et al, and the improvement of doping Mo is more obvious than that of doping Ni.
This research is that cellulose/poly-silicate hybrid material was prepared with viscose and poly-silicate by sol-gel method. The influence of aluminum salt and poly-silicate on hybrid material thermal property was stu...
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This research is that cellulose/poly-silicate hybrid material was prepared with viscose and poly-silicate by sol-gel method. The influence of aluminum salt and poly-silicate on hybrid material thermal property was studied. Based on the analysis of the DSC and TG curve of hybrid material, we have found that the hybrid material has splendid heat-resistance and fire retardancy.
The α-Fe fibers were prepared successfully by the method of electrodepositing in porous alumina template. The results indicated that the diameter of the fibers was 300 nm and the length of them increased along with t...
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The α-Fe fibers were prepared successfully by the method of electrodepositing in porous alumina template. The results indicated that the diameter of the fibers was 300 nm and the length of them increased along with the electrodepositing time increasing. The saturation magnetization per m2 of the iron fibers increased with the increasing of the length/diameter ratio, but the coercive field decreased.
The transport dynamics of proton exchange membrane fuel cell( PEMFC) is very important to understand its working mechanism and to realize optimization control. A single-channel, three-dimensional model has been develo...
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The transport dynamics of proton exchange membrane fuel cell( PEMFC) is very important to understand its working mechanism and to realize optimization control. A single-channel, three-dimensional model has been developed to study the change of relative humidity of reactant and current density;Dynamic simulation includes average number of H2O/SO42- of membrane surface at cathode, diffusion of oxygen, pressure of channel inlet/outlet, gas flow rate and so on. The conclusion has reference significance regarding the correlated research.
Microstructures of highly compact IrO2 films, deposited on Si (100) substrates by pulsed laser deposition of Ir target at different oxygen partial pressures, were characterized with X-ray diffraction (XRD), Raman spec...
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Microstructures of highly compact IrO2 films, deposited on Si (100) substrates by pulsed laser deposition of Ir target at different oxygen partial pressures, were characterized with X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM) and atomic force microscopy (AFM).The results show that the films, grown at an oxygen partial pressure of 20 Pa and at a substrate temperature in the range of 250°-500°C, are polycrystalline and that as the substrate temperature rises, IrO2 surface becomes rougher with bigger grains.
Highly ordered CoFe2O4 nanowire arrays were prepared in anodic aluminum oxide (AAO) templates with two diameters (50 nm and 200 nm) by Sol-gel method. The scanning electron microscope (SEM), transmission electron micr...
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Highly ordered CoFe2O4 nanowire arrays were prepared in anodic aluminum oxide (AAO) templates with two diameters (50 nm and 200 nm) by Sol-gel method. The scanning electron microscope (SEM), transmission electron microscope (TEM) and high-resolution transmission electron microscope (HRTEM) were used to characterize the structures of the nanowire arrays. The hysteresis loops of the CoFe2O4 nanowire arrays reveal that there was no preferential magnetic orientation in both of the nanowire arrays with different diameters. The measured coercivity of CoFe2O4 nanowire arrays with smaller diameter (50 nm) was larger than that of the nanowire arrays with bigger diameter (200 nm). The possible explanation for this behavior was given.
Titanium diboride based composites, good candidates for contact materials, have high hardness, Young＇s modulus, high temperature stability, and excellent electrical, thermal conductivity. However a good interface of ...
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Titanium diboride based composites, good candidates for contact materials, have high hardness, Young＇s modulus, high temperature stability, and excellent electrical, thermal conductivity. However a good interface of TiB2/Cu is very difficult to achieve for oxidation of TiB2. To avoid this oxidation behavior, the in situ combusting synthesistechnology, SHS, was used to prepare TiB2/Cu composite. The characters of Ti-B-xCu SHS were studied in detail, such as combustion temperature, products phases and grain size. Based on the experimental results a proper technology way of self-high temperature synthesis plus quick press （SHS/QP） was determined and compact TiB2/Cu composites with relative density over than 97 pct of the theoretical were fabricated by this method. The properties and microstructures of these TiB2 based composites were also investigated.
The article reported a method of boronize medium absorbing microwave to fabricate boronization layer in the steel surface, and compares it with traditional boronization. The results indicated that the boron atoms for ...
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The article reported a method of boronize medium absorbing microwave to fabricate boronization layer in the steel surface, and compares it with traditional boronization. The results indicated that the boron atoms for the development of boronization layer were rooted in those produced by medium decomposition and gaseous boride, just like the traditional boronization. The growth of boronization layer in microwave was characterized with less than or equal 002> crystal orientation. Its growth rate of boronization layer was faster than that in traditional treatment. Besides temperature effect, growth rate was also influenced by activity boron atom in microwave diffusion in boronization layer.
The residual stresses on the surface of the d ifferently ground and polished silicon nitride ceramics were measured using X-r ay diffraction and identified by *** effect of the residual stress on the be nding strengt...
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The residual stresses on the surface of the d ifferently ground and polished silicon nitride ceramics were measured using X-r ay diffraction and identified by *** effect of the residual stress on the be nding strength was *** investigations show that the grinding proces s can introduce subatantial tensile residual stresses up to 290MPa on the surfac e of silicon nitride ceramics,which has a significant effect on reducing the ben ding strength of the ceramics after ***,in comparison with the ceramic s with a rough surface,the ceramics with a mirror image surface may have a lower *** can smooth the residual *** we evaluate the qualit y of the ceramic components after grinding,we must take residual stress into con sideration. The grinding methods and grinding conditions must be carefully selec ted in order to get the favorite residual stress as well as the surface smoothne ss.
The PAn-PEO-PAn triblock copolymer with the PEG chain length of 400 was synthesized by chemical oxidation copolymerization of aniline and α,ω-bis（p-aminophenyl）poly（ethylene glycol）and characterized by FT-IR and...
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The PAn-PEO-PAn triblock copolymer with the PEG chain length of 400 was synthesized by chemical oxidation copolymerization of aniline and α,ω-bis（p-aminophenyl）poly（ethylene glycol）and characterized by FT-IR and *** experimental results show that the copolymer particles are of μtypical core-shell structure after the self-assembly process in *** conductivity is much lower than that of the pure *** suspension containing 20 vol% PAn-PEO-PAn tiblock copolymer in silicone oil exhibits.a typical electrorheological （ER） effect in DC electric *** it shows a lower leakage current density than that of the pure PAn-based ER ***,the PEO shell hinders the electric hop among PANI chains and decreases the current density of ER fluids in an external electric *** the same time the interface polarity improves the ER effects.
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