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951.
A methodology remediating zones of local radioactive contamination is presented. It is based on a classification of the zones taking account of the contribution of external and internal irradiation to the total dose load to the public. The criteria for identifying such loads and the steps required for their remediation are identified. A radiation-ecological validation of the decrease in the external irradiation dose to the public in zones of local radioactive contamination is given. __________ Translated from Atomnaya énergiya, Vol. 100, No. 2, pp. 125–134, February, 2006.  相似文献   
952.
The film-forming capacity of binary systems containing Sb2O3, SnO2, CeO2, Y2O3, Nd2O3, Bi2O3, V2O5, ZnO, CuO, CdO, and Al2O3 are investigated. The best film-formers are Sb2O3 and SnO2, whereas ZnO, CuO, CdO, and Al2O3 cannot produce films of optical quality. The rest of considered oxides do not impair the clarity of coatings when their molding content is 20 – 50%. A proportional dependence is established between the refractive index and the reflection coefficient of a film and the refractive indexes of oxides making parts of this film, as well as between the concentration of deposited FFS, the film-forming capacity of oxides, and the film thickness.  相似文献   
953.
954.
Solution-processed n-type organic field-effect transistors (OFETs) based on the fullerene derivative {6}-1-(3-(2- thienylethoxycarbonyl)-propyl)-{5}-l-phenyl-[5,6]-C61 (TEPP) and phenyl-C61-butyric acid methyl ester (PCBM) in a multiring source/drain structure are reported. Devices with TEPP show high electron mobility up to 7.8 x 10-2 cm2/Vs in the saturation regime for bottom-contact OFETs with Au S/D electrodes with a solution-processed fullerene derivative. The ON/OFF ratios reported in this letter, which are in the range of 105 -106, are among the highest values reported for such devices. This mobility is always higher compared to PCBM devices prepared in identical conditions. The mobility of TEPP and PCBM increased with increasing temperatures in the range of 100-300 K with activation energy of 78 and 113 meV, respectively, which suggests that the thermally activated hopping of electrons is dominant in TEPP.  相似文献   
955.
In this paper, the authors use an analytical model to calculate the losses in the metallized polypropylene film capacitors. The model is validated experimentally for capacitors having the same capacitance but different geometry. For each group of capacitors, a temperature distribution in the roll is assumed with the aim of optimizing its thermal performance. It appears that the heating of a long capacitor is higher than that of an equivalent flat capacitor subjected to the same electric stresses  相似文献   
956.
Metal Science and Heat Treatment -  相似文献   
957.
Mesh network resiliency using GMPLS   总被引:4,自引:0,他引:4  
The generalized multiprotocol label switching (GMPLS) is being developed as the control plane for the evolving photonic network. We describe how GMPLS can be used with mesh networks to provide efficient network resiliency. In particular we examine the key aspects of GMPLS that are used to support protection and restoration. We also study the various protection and restoration techniques, and we highlight the tradeoffs between recovery time and resource redundancy  相似文献   
958.
介绍一种新型的恒通量的微滤膜———ISOFLUX 膜 ,该种膜的膜通量衰减比通常的微滤膜要小得多 ,对ISOFLUX 膜的原理和数学模型进行了推导 ,并给出了对牛奶进行冷杀菌过滤的结果 .  相似文献   
959.
This study investigates quantitatively and qualitatively the sol-gel derived bioactive glass-ceramic system (BGS)—apatite-wollastonite (AW) type granules in the size range of 0.5–1 mm, as an effective graft material for bone augmentation and restoration. Scanning electron micrographs (SEM) of the sintered granules revealed the rough material surface with micropores in the range 10–30 μm. X-ray diffraction (XRD) pattern of the granules revealed the presence of crystalline phases of the hydroxyapatite and wollastonite, and the functional groups of the silicate and phosphates were identified by Fourier transform infrared spectroscopy (FT-IR). Thein vitro cell culture studies with L929 mouse fibroblast cell line showed very few cells adhered on the BGS disc after 24 h. This could be due to the highly reactive surface of the disc concomitant with the crystallization but not due to the cytotoxicity of the material, since the cellular viability (MTT assay) with the material was 80‰ Cytotoxicity and cytocompatibility studies proved that the material was non-toxic and biocompatible. After 12 weeks of implantation of the BGS granules in the tibia bone of New Zealand white rabbits, the granules were found to be well osteointegrated, as observed in the radiographs. Angiogram with barium sulphate and Indian ink after 12 weeks showed the presence of microcapillaries in the vicinity of the implant site implicating high vascularity. Gross observation of the implant site did not show any inflammation or necrosis. SEM of the implanted site after 24 weeks revealed good osteointegration of the material with the newly formed bone and host bone. New bone was also observed within the material, which was degrading. Histological evaluation of the bone healing with the BGS granules in the tibial defect at all time intervals was without inflammation or fibrous tissue encapsulation. After 2 weeks the new bone was observed as a trabeculae network around the granules, and by 6 weeks the defect was completely closed with immature woven bone. By 12 weeks mature woven bone was observed, and new immature woven bone was seen within the cracks of the granules. After 24 weeks the defect was completely healed with lamellar bone and the size of the granules decreased. Histomorphometrically the area percentage of new bone formed was 67.77% after 12 weeks and 63.37% after 24 weeks. Less bone formation after 24 weeks was due to an increased implant surface area contributed by the material degradation and active bone remodeling. The osteostimulative and osteoconductive potential of the BGS granules was established by tetracycline labelling of the mineralizing areas by 2 and 6 weeks. This sol-gel derived BGS granules proved to be bioactive and resorbable which in turn encouraged active bone formation.  相似文献   
960.
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