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  • Author or Editor: R. S. Pathak x
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Вводятся два простра нства тест-функцийH μ,M,a иH μ,b Ω. Изучаются их счетные объеди-нения — пространстваH μ,M иH μ Ω. Р ассматриваются топологические и алг ебраические свойства этих простр анств. Доказано, что преобразование Ганк еляH μ,μ≧−1/2, является изоморфизмом изH μ,H,a наH μ Ω,1/a и и изH μ,M наH μ Ω. Строится операционное исчисл ение, которое применяется для решения одной обо бщенной граничной задачи.

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Вводится продолжение функцио налов с пространства на , гдеc kb k. Такие функционалы ха рактеризуются в терм инах их роста на бесконечнос ти. Исследуется также пр одолжение функциона лов в пространстве мульти пликаторов. Накладываются разли чные условия роста го ломорфных функций в трубчатых областях и исследует ся рост соответствую щих специальных функций.

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Abstract  

Porous zirconia spherical particles have been prepared by internal gelation process. During preparation of these spherical particles, a cationic surfactant, cetrimide was added in the feed broth to increase the surface area and porosity of the particles. The sorption behavior of plutonium was investigated on this material from different complexing aqueous media from the recovery point of view. Distribution ratio studies have been carried out to investigate the effect of varying concentrations of oxalic acid, phosphoric acid, sulphuric acid, nitric acid, sodium carbonate and sodium bicarbonate to optimize the conditions of sorption of plutonium on this ion exchange material.

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Abstract  

The radiolytic stability of a branched diglycolamide extractant, namely N,N,N′,N′-tetra-2-ethylhexyl diglycolamide (T2EHDGA) dissolved in n-dodecane containing several phase modifiers, viz. N,N-dihexyloctanamide (DHOA), tri-n-butyl phosphate (TBP), 1-decanol and iso-decanol has been investigated. The distribution ratio of Am(III) decreased with increased radiation dose studied up to 1000 kGy. Nevertheless, all the composition of extractants showed satisfactory results up to 500 kGy, beyond which the extractants degraded drastically. The stripping behaviour of Am(III) with 0.2 M HNO3 was found to be unaffected even with the ligand solution irradiated up to 1000 kGy. Extraction of fission product and structural elements was also investigated using the irradiated solvents and was found to be not significantly affected with increasing absorbed dose with the exception of Mo which showed sharp rise in the distribution coefficient values. Loading of Nd in the organic phase decreased with the irradiated solvent due to degradation of the carrier. The effect of the absorbed dose on physical parameters such as density, viscosity and interfacial tension of the solvents has also been investigated.

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Abstract  

The paper aims to investigate cytogenetic and apoptotic responses of γ-irradiation in a radio-resistant cell strain designated as M5. Induced micronuclei, chromosomal aberrations, nuclear fragmentation and nucleosomal ladders by γ-irradiation were less at equal doses in M5 cells in comparison with that obtained in the parental Chinese hamster V79 cells. However, at equal survival, there were no differences in the end points studied. Results indicate that the residual damages that lead to reproductive cell death also resulted in the cytogenetic and apoptotic responses. We speculate that the repair efficiency in M5 cells was more efficient and increased DNA repair could be the cause of radiation resistance observed in M5 cells.

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A purified alkaline thermo-tolerant bacterial lipase from Pseudomonas aeruginosa MTCC-4713 was immobilized on a poly (AAc-co-HPMA-cl-MBAm) hydrogel. The hydrogel-bound lipase achieved 93.6% esterification of ethanol and propionic acid (300 mM: 100 mM) into ethyl propionate at temperature 65oC in 3 h in the presence of a molecular sieve (3 Å). In contrast, hydrogel-immobilized lipase pre-exposed to 5 mM of HgCl2 orNH4Cl resulted in approximately 97% conversion of reactants in 3 h into ethyl propionate under identical conditions. The salt-exposed hydrogel was relatively more efficient in repetitive esterification than the hydrogel- bound lipase not exposed to any of the cations. Moreover, bound lipase exposed Hg2+ or NH4 + ions showed altered specificity towards p-nitrophenyl esters and was more hydrolytic towards higher C-chain p-nitrophenyl esters (p-nitrophenyl laurate and p-nitrophenyl palmitate with C 12 and C 16 chain) than the immobilized lipase not exposed to any of the salts. The later showed greater specificity towards p-nitrophenyl caprylate (C 8).

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