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51.
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Sarbjit Singh Amol Mhatre Veena Sagar 《Journal of Radioanalytical and Nuclear Chemistry》2012,294(1):7-11
The segmented gamma ray scanning system developed for the assay of plutonium present in 200?L waste drums was modified for the estimation of gram amounts of plutonium in the presence of high beta gamma activity. A multi gamma ray source of 152Eu having?~1?mCi activity was used for the determination of attenuation correction factors for high count rate drums. Dead time corrections were applied to arrive at the corrected count rates for all the gamma rays. Present study has shown that the estimation of?~1?g of 239Pu in a waste drum can be carried out in the presence of 137Cs up to an activity level of 20?mCi. 相似文献
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Sagar Biswas 《Physics letters. [Part B]》2011,701(4):481-484
We study rigidly rotating strings in the near-horizon geometry of a stack of Neveu-Schwarz (NS) 5-branes. We solve the Nambu-Goto action of the fundamental string in the presence of a NS-NS two form (Bμν) and find out limiting cases corresponding to magnon and spike like solutions. 相似文献
55.
V. B. Sagar M. S. Oak S. M. Pawar C. K. Sivaramakrishnan S. K. Patil 《Journal of Radioanalytical and Nuclear Chemistry》1991,150(1):29-34
Extraction studies have been carried out to explore the feasibility of separation of Pu(IV) from phosphate containing analytical wastes generated in the laboratory. Distribution data on the extraction of Pu(IV) from DBDECMP (di-butyl, N,N-diethylcarbamoyl methyl phosphonate) in xylene from an aqueous nitric acid and its mixture with sulfuric as well as with sulfuric and phosphoric acids were obtained. Based on the data obtained, the conditions for the recovery of plutonium from such waste solutions are suggested. 相似文献
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Synthesis,Structure, Bonding,and Reactivity of Metal Complexes Comprising Diborane(4) and Diborene(2): [{Cp*Mo(CO)2}2{μ‐η2:η2‐B2H4}] and [{Cp*M(CO)2}2B2H2M(CO)4], M=Mo,W 下载免费PDF全文
Dr. Bijan Mondal Ranjit Bag Sagar Ghorai Dr. K. Bakthavachalam Prof. Eluvathingal D. Jemmis Prof. Sundargopal Ghosh 《Angewandte Chemie (International ed. in English)》2018,57(27):8079-8083
The reaction of [(Cp*Mo)2(μ‐Cl)2B2H6] ( 1 ) with CO at room temperature led to the formation of the highly fluxional species [{Cp*Mo(CO)2}2{μ‐η2:η2‐B2H4}] ( 2 ). Compound 2, to the best of our knowledge, is the first example of a bimetallic diborane(4) conforming to a singly bridged Cs structure. Theoretical studies show that 2 mimics the Cotton dimolybdenum–alkyne complex [{CpMo(CO)2}2C2H2]. In an attempt to replace two hydrogen atoms of diborane(4) in 2 with a 2e [W(CO)4] fragment, [{Cp*Mo(CO)2}2 B2H2W(CO)4] ( 3 ) was isolated upon treatment with [W(CO)5?thf]. Compound 3 shows the intriguing presence of [B2H2] with a short B?B length of 1.624(4) Å. We isolated the tungsten analogues of 3 , [{Cp*W(CO)2}2B2H2W(CO)4] ( 4 ) and [{Cp*W(CO)2}2B2H2Mo(CO)4] ( 5 ), which provided direct proof of the existence of the tungsten analogue of 2 . 相似文献
58.
Sagar Sharma Rajesh S. Baligar Harkesh B. Singh Prof. Ray J. Butcher Prof. 《Angewandte Chemie (International ed. in English)》2009,48(11):1987-1990
All wrapped up : The reaction of a 22‐membered macrocycle derived from bis(o‐formylphenyl)mercury and 1,2‐phenylenediamine with palladium(II) results in cleavage of the macrocycle and concomitant formation of a trimetallic complex (see picture; phenyl rings truncated for clarity). The nature of the HgII???PdII???HgII interaction was investigated by theoretical studies.
59.
A cost-effective and eco-friendly synthesis of 2-aryl-1-arylmethyl-1H-benzimidazoles has been developed through the condensation of different aldehydes with o-phenylenediamine using alumina-sulfuric acid as a recyclable heterogeneous solid acid catalyst. Morphological properties of the catalyst have been investigated. Effect of different solvents and comparison of alumina-sulfuric acid with different acid catalysts have also been studied. A plausible mechanistic pathway has been proposed on the basis of the isotope labelling experiments where catalytic behaviour of alumina-sulfuric acid has been explained. 相似文献
60.
ZnII‐ and AuI‐Catalyzed Regioselective Hydrative Oxidations of 3‐En‐1‐ynes with Selectfluor: Realization of 1,4‐Dioxo and 1,4‐Oxohydroxy Functionalizations 下载免费PDF全文
Dr. Appaso Mahadev Jadhav Sagar Ashok Gawade Dr. Dhananjayan Vasu Dr. Ramesh B. Dateer Prof. Dr. Rai‐Shung Liu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(7):1813-1817
Catalytic 1,4‐dioxo functionalizations of 3‐en‐1‐ynes to (Z)‐ and (E)‐2‐en‐1,4‐dicarbonyl compounds are described. This regioselective difunctionalization was achieved in one‐pot operation through initial alkyne hydration followed by in situ Selectfluor oxidation. The presence of pyridine alters the reaction chemoselectivity to give 4‐hydroxy‐2‐en‐1‐carbonyl products instead. A cooperative action of pyridine and ZnII assists the hydrolysis of key oxonium intermediate. 相似文献