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111.
Effect of Mn-doping on the growth mechanism and electromagnetic properties of chrysanthemum-like ZnO nanowire clusters
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Chrysanthemum-like ZnO nanowire clusters with different Mn-doping concentrations are prepared by a hydrothermal process. The microstructure, morphology and electromagnetic properties are characterized by x-ray diffractometer high-resolution transmission electron microscopy (HRTEM), a field emission environment scanning electron microscope (FEESEM) and a microwave vector network analyser respectively. The experimental results indicate that the as-prepared products are Mn-doped ZnO single crystalline with a hexagonal wurtzite structure, that the growth habit changes due to Mn-doping and that a good magnetic loss property is found in the Mn-doped ZnO products, and the average magnetic loss tangent tanδm is up to 0.170099 for 3% Mn-doping, while the dielectric loss tangent tanδe is weakened, owing to the fact that ions Mn2 + enter the crystal lattice of ZnO. 相似文献
112.
Effect of polyacrylamide on morphology and electromagnetic properties of chrysanthemum-like ZnO particles
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Through hydrothermal process, the chrysanthemum-like ZnO particles
are prepared with zinc acetate dihydrate (Zn(CH3COO)2\cdot
2H2O) and sodium hydroxide (NaOH) used as main resources under
the different concentrations of surfactant polyacrylamide (PAM). The
microstructure, morphology and the electromagnetic properties of the
as-prepared products are characterized by high-resolution
transmission electron microscopy (HRTEM), field emission environment
scanning electron microscope (FEESEM) and microwave vector network
analyzer, respectively. The experimental results indicate that the
as-prepared products are ZnO single crystalline with hexagona
wurtzite structure, that the values of slenderness ratio L_d are
different in different PAM concentrations, and that the good
magnetic loss property is found in the ZnO products, and the average
magnetic loss tangent tanδu increases with PAM
concentration increasing, while the dielectric loss tangent
tanδ e decreases. 相似文献
113.
Cr-doped CdS nanowires were synthesized in large scale through thermal
co-evaporation of CdS and metal Cr powders. General morphology, detailed
microstructure and optical properties were characterized using various
techniques. Devices consisting of individual Cr-doped CdS nanowire were
fabricated and they exhibited remarkable rectifying characteristics.
I-V curves of individual Cr-doped CdS nanowire devices demonstrate that the
present nanowires are n-type doped and have high conductivity (10.96 \Omega
-1cm-1, indicating great potential applications in nanoscale
electronic and optoelectronic devices. 相似文献
114.
Polarization calibration unit(PCU) has become an indispensable element for solar telescopes to remove the instrumental polarization; the polarimetric accuracy of calibration depends strongly on the properties of PCU. In the paper, we analyze the measurement errors induced by PCU based on polarized light theory and find that the imperfections of the waveplate generate the main calibration errors. An optimized calibration method is proposed to avoid the effects from waveplate imperfections, and a numerical simulation is given to evaluate the polarization accuracy by analyzing the relation between calibration error and intensity instability. The work is very important for solar telescopes with high polarization precision up to 10~(-4) I_c. 相似文献
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116.
The effect of In doping on the electronic structure and optical properties of SrTiO3 is investigated by the first-principles calculation of plane wave ultra-soft pseudo-potential based on the density function theory (DFT). The calculated results reveal that due to the hole doping, the Fermi level shifts into valence bands (VBs) for SrTi1-x InxO3 with x = 0.125 and the system exhibits p-type degenerate semiconductor features. It is suggested according to the density of states (DOS) of SrTi0.875In0.125O3 that the band structure of p-type SrTIO3 can be described by a rigid band model. At the same time, the DOS shifts towards high energies and the optical band gap is broadened. The wide band gap, small transition probability and weak absorption due to the low partial density of states (PDOS) of impurity in the Fermi level result in the optical transparency of the film. The optical transmittance of In doped SrTiO3 is higher than 85% in a visible region, and the transmittance improves greatly. And the cut-off wavelength shifts into a blue-light region with the increase of In doping concentration. 相似文献
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