After combining the PVDF and BST powders with different particle sizes, the anti-voltage strengths of composites was tested. Although the concentrates of ceramic were all the same, their anti-voltage strengths were di...
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Cobalt-rich filled skutterudite compounds CeyFexCo4-xSb12 (y=0-0.42) are synthesized using the melting-diffusion method. The structure and thermoelectric properties of the compounds are investigated. Results indicate ...
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Cobalt-rich filled skutterudite compounds CeyFexCo4-xSb12 (y=0-0.42) are synthesized using the melting-diffusion method. The structure and thermoelectric properties of the compounds are investigated. Results indicate that the lattice constants increase linearly with the Ce filling fraction. Hall coefficient is positive. Hole concentration and electrical conductivity decreased as the Ce filling fraction increases. Seebeck coefficient increase with the Ce filling fraction. The lattice thermal conductivity reached the minimum value when the Ce filling fraction was about 0.29, indicating that the effect of Ce rattling on phonon scattering is the strongest as Sb-dodecahedron partial voids are filled by Ce. A maximum ZT value of 0.65 is obtained for Ce0.29Fe1.41Co2.59Sb12.32 at 725 K.
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.
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.
TiB2 powders coated with BN were prepared by Hybridization System making use of dry impact blending method to achieve powder surface modification. Parameters of coating were analyzed and the most appropriate condition...
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TiB2 powders coated with BN were prepared by Hybridization System making use of dry impact blending method to achieve powder surface modification. Parameters of coating were analyzed and the most appropriate condition was summarized. Scan electron microscope of JSM-5610LV and transmission electron microscope of H-600STEM/EDS were used to observe the microstructure of coated powders. Results show that treatment time, rotation speed, granularity ratio of TiB2 to BN, pretreatment of materials etc influence the coating results evidently. Mixing raw materials and coating with BN under the appropriate condition can get round TiB2/BN composite powder with smooth surface and compact coating layer.
A new organic-inorganic hybrid compound (dienHs)2(P2Mo5O23) (1) [dien=NH(CH2CH2NH2)2] has been hydrothermally synthesized and characterized by elemental analyses, IR spectrum, thermogravimetric analysis, and t...
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A new organic-inorganic hybrid compound (dienHs)2(P2Mo5O23) (1) [dien=NH(CH2CH2NH2)2] has been hydrothermally synthesized and characterized by elemental analyses, IR spectrum, thermogravimetric analysis, and the single crystal X-ray diffraction technique. Compound 1 crystallizes in the triclinic system with space group P1 and a=0.9790(2) nm, b=0.9922(2) nm, c= 1.4644(3) nm, α=95.510(10)°, β=98.860(10)°, γ=95.700(10)°, V=1.3895(5) nm^3, Z=2, R=0.0465. The results show that the compound consists of dienH3^3++ and P2Mo5O23^6-, and the heteropoly anion P2Mo5O23^6- is connected to a 1-D chain structure with the protonated dien by hydrogen bonds.
TiO2 thin films were prepared on soda lime glass, fused quartz and stainless steel substrates by liquid phase deposition (LPD) method from a (NH4)2TiF6 aqueous solution upon the addition of boric acid (H3BO3), and the...
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TiO2 thin films were prepared on soda lime glass, fused quartz and stainless steel substrates by liquid phase deposition (LPD) method from a (NH4)2TiF6 aqueous solution upon the addition of boric acid (H3BO3), and then calcined at 500°C for 2 h. The prepared films were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). It was found that the substrates obviously influenced the element composition and microstructure of TiO2 thin films. Except Ti, O and a small amount of F and N elements, which came from the precursor solution, some Si (or Fe) element in the thin films deposited on soda lime glass and quartz substrates (or on stainless steel substrate) was confirmed. The Si (or Fe) element in the thin films could be attributed to two sources. One was from the SiF 62- ions (or FeF62- ions) formed by a reaction between the treatment solution and soda lime glass or quartz (or stainless steel) substrates. The other was attributed to the diffusion of Si (or Fe) from the surface of substrates into the TiO2 thin films after calcination at 500°C. The Si (or Fe) element in the TiO2 thin films could behave as a dopant and resulted in the formation of composite SiO2/TiO2 (or Fe2O3/TiO2) thin films on the substrates.
Preparation of a modified (Pb,Ca)TiO3 with (Zn1/2W1.2) (Ni1/2Nb1/2) substitution in B-site had been studied. Adding suitable amounts of MnCO3 in this modified PbTiO3 piezoelectric ceramics, the material performances c...
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