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Summary Hydrophilic endohedral 133Xe-fullerenols, [133Xe@C60(OH)xand 133Xe@C70(OH)x], were synthesized from hydrophobic endohedral 133Xe-fullerenes. The yield of endohedral 133Xe-fullerenols extracted in water was about 40% and 23% for C60and C70, respectively. The products stored in 0.9% NaCl solution at 20 °C were stable enough to be used in nuclear medicine.  相似文献   
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Random walk properties and correlation factors for diffusion via the vacancy mechanism are calculated and compared for various three-dimensional lattices. By applying the theory of random walks on an imperfect lattice, the correlation factor for impurity diffusion is calculated rigorously for the five jump frequency model in the fee lattice.Presented at the Symposium on Random Walks, Gaithersburg, MD, June 1982.  相似文献   
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Ion implantation was applied to the production of endohedral 133Xe-fullerene. Using an isotope separator, 133Xe ions were implanted into a fullerene target of C60 and C70 produced by vacuum evaporation on a Ni backing. An HPLC analysis following dissolution of the fullerene targets in o-dichlorobenzene corroborated the formation of 133Xe@C60 and 133Xe@C70, showing a strong correlation between C60/C70 and 133Xe. The observed tailing following 133Xe peaks in the elution curves suggests a possibility of the isolation of endohedral 133Xe-fullerene from empty fullerene.  相似文献   
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p‐Dodecylbenzenethiol (1) and p‐octyloxybenzenethiol (2) were synthesized as new odorless benzenethiols. Moreover, preparation of novel 1‐thioglycosides using 1 and 2 as well as their application for glycosylation reactions was performed. As a result, it was found that these 1‐thio‐glycosides were excellent glycosyl donors, and especially 2‐thio‐sialoside prepared from 1 and 2 afforded the best result to date in terms of α‐ and β‐selectivity in the sialylation where only the single C‐3 hydroxyl group of acceptor D‐galactopyranoside was free. All procedures from the preparation of thioglycosides to glycosylation reaction were attainable under completely odorless conditions.  相似文献   
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0Introduction Anelectronicpackageisgenerallyconstructedwithanactivesiliconchip,mountisland,gold wires,leadframesandsoldersasshowninFig.1(a).Toprotectfromtheenvironment,thesilicon chipisusuallyencapsulatedinresin.SincethesematerialshavedifferentCTE(coeffic…  相似文献   
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Pseudo-random properties of a class of two-dimensional (2-D) 5-neighborhood cellular automata (CA), built around nonlinear (OR, AND) and linear (XOR) Boolean functions are studied. The site values at each step of the 2-D CA evolution are taken in parallel and form pseudo-random sequences, which satisfy the criteria established for pseudo random number generator (PRNG): long period, excellent random qualities, single bit error propagation (avalanche criteria), easy and fast generation of the random bits. A block-scheme for secure Stream Cipher based on 2-D CA is proposed. The 2-D CA based PRNG algorithm has simple structure, use space-invariant and local interconnections and can be easily realized in very large scale integration or parallel optoelectronic architectures.  相似文献   
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The correlation time for motional narrowing of a Mössbauer resonance line (181Ta) by hydrogen diffusion has been calculated by applying the random walk theory. The correlation times τc are 12.546 541τ and 3.756 711τ for tetrahedral and octahedral occupancies, respectively, where τ is the mean residence time of a hydrogen atom.  相似文献   
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The sound attenuation coefficient due to the critical fluctuations of the order parameter is formulated in the isotropic phase of nematics by taking account of the mode-coupling effects between the order parameter and the hydrodynamic shear mode. The result is compared with the available experimental data.  相似文献   
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