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141.
A non-static Bianchi type-III domain walls cosmological models in presence and absence of magnetic field are investigated in general theory of relativity. We assume that F 12 is only the non-vanishing component of F ij . To obtain deterministic model, we assume relations B=C n and ρ=p. Some physical properties of these models are discussed.  相似文献   
142.
Room temperature chemical synthesis of PbSe thin films was carried out from aqueous ammoniacal solution using Pb(CH3COO)2 as Pb2+ and Na2SeSO3 as Se2− ion sources. The films were characterized by a various techniques including, X-ray diffraction (XRD), energy dispersive X-ray analysis (EDAX), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HR-TEM), selected area electron diffraction (SAED), Fast Fourier transform (FFT) and UV-vis-NIR techniques. The study revealed that the PbSe thin film consists of preferentially oriented nanocubes with energy band gap of 0.5 eV.  相似文献   
143.
The zinc selenide thin films have been deposited using modified chemical bath deposition (M-CBD) method. Zinc acetate and sodium selenosulphate were used as Zn2+ and Se2− ion sources, respectively. The preparative parameters such as concentration, pH, number of deposition cycles have been optimized in order to deposit ZnSe thin films. The as-deposited ZnSe thin films are specularly reflective and faint yellowish in color. The as-deposited ZnSe films are annealed in an air atmosphere at 473 K for 2 h. The films are characterized using structural, morphological, compositional, optical and electrical properties.  相似文献   
144.
145.
The present paper discusses the development of the NaCl:K (10 –1 molar fraction of potassium) phosphor as dosimeter material for beta-radiation thermoluminescent dosimetry (TLD). The TLD grade NaCl:K(6T) material was prepared by annealing the NaCl:K powder obtained from aqueous solution by the method of recrystalization and annealed at 600°C for two hours in open air. It is observed that thermal glow curves of NaCl:K(6T) specimen exhibit well defined glow peak around 170°C alongwith a weaker peak at lower temperature. The high-temperature peak is found to grow supralinearily with increase in beta dose in the range 10–2×103 rad. Since the nature of glow curves under the influence of different doses remains more or less identical, it is believed that the phosphor does not undergo radiation damage and give high intrinsic TL around peak III. Examination of the system for fundamental dosimetry requirement shows that the NaCl:K(6T) material can be used as a suitable TLD material in beta radiation.  相似文献   
146.
A novel, catalyst-free strategy for the direct synthesis of vertically aligned silicon nanowire-carbon nanotube (SiNW-CNT) heterojunction arrays is presented. Such a heterojunction with the junction area in the nanoscale displays enhanced field emission characteristics at low turn-on field, with a nearly three times increase in the field enhancement factor.  相似文献   
147.
A facile, simple, and high-yielding synthetic protocol for novel glycosyl tetrazoles has been devised from different carbohydrate-containing amides using benzotriazole methodology under mild reaction condition.  相似文献   
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