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排序方式: 共有454条查询结果,搜索用时 15 毫秒
1.
Dipak Ghosh Madhumita Lahiri Argha Deb Susobhan Das Krishnadas Purkait Biswanath Biswas Jayanta Roy Choudhury Rini Chatterjee Abdul Kayum Jafry 《Zeitschrift fur Physik C Particles and Fields》1996,71(1):243-249
The scaled factorial moments and the multifractal moments have been investigated in differentη-intervals to study the dynamical fluctuation of pions produced in 200 AGeV32S-Ag/Br interaction. In order to investigate the detail characteristics of intermittency behaviour, theF-moments are extracted up to the eighth order of moments in differentM-intervals. The analysis indicates a non-thermal phase transition and different regime of particle production during the hadronisation process. 相似文献
2.
N. Jiten Singh Adriana C. Olleta Anupriya Kumar Mina Park Hai-Bo Yi Indrajit Bandyopadhyay Han Myoung Lee P. Tarakeshwar Kwang S. Kim 《Theoretical chemistry accounts》2006,115(2-3):127-135
In earlier studies, the interactions of isolated ionic species with various solvents were investigated using ab initio calculations.
The ionic species investigated included cations (proton, hydronium, ammonium, and metal cations) and anions (single electron,
hydroxide, and halide anions). However in the present study, we investigate the interactions of these ionic species with the
solvent in the presence of other competing ionic species. We also elaborate on how the information obtained from these extensive
studies have been employed in designing and synthesizing various kinds of novel ionophores and receptors. 相似文献
3.
Summary Studies on adsorption behavior of heavy radionuclides, present altogether in no-carrier-added state, e.g., 197-200Pb, 197-200Tl and 197Hg, have been carried out with calcium alginate beads. High lead (100%) and moderate thallium removal (~65%) was achieved
in pH range 2-7. 100% mercury removal was also achieved at pH 2 and 4. Effort has been made to recover all three radionuclides
adsorbed in the calcium alginate beads using various chemicals, such as HCl, thiourea, sodium acetate, sodium oxalate and
sodium nitrite. It was found that 0.1M HCl and 0.1M thiourea could remove at pH 1 80-90% of adsorbed Pb. Tl recovery was possible
by all chemicals mentioned above. Hg was also recovered by all chemicals except HCl. 相似文献
4.
The reaction of cycloheptatriene (CHT) with dibenzoylacetylene (DBA), in refluxing toluene gave a mixture of products consisting of 6,7-dibenzoyltricyclo[3.2.2.02.4]nona-6,8-diene 6 and 3,4-dibenzoylbicyclo [3.2.2]nona-2,6,8-triene 7. Neat heating of a mixture of CHT and DBA around 95–100° gave besides, 6 and 7, small amounts of two dimers of DBA. Photolysis of 6 in benzene solution gave a lactonic, rearrangement product. 25. The structures of the various products have been established and reasonable mechanisms for their formation have been suggested. 相似文献
5.
Indrajit Kar B. M. Mandal S. R. Palit 《Journal of polymer science. Part A, Polymer chemistry》1969,7(10):2829-2836
Chain transfer constants of some fluoroalcohols [HCF2(CF2)n?1CH2OH, n = 2, 4, 6] in the catalyzed polymerization of vinyl acetate, styrene, acrylonitrile, and methyl methacrylate at 60°C have been evaluated by a method based on degree of polymerization. Since fluoroalcohols are normally nonsolvents for polymers, a homogeneous reaction phase is maintained by carrying out the polymerization in benzene (except in case of acrylonitrile, where no solvent was used). The transfer constants vary, depending on the reactivity as well as the polarity of the radicals, in the following order: vinyl acetate > styrene > methyl methacrylate > acrylonitrile. Of the three fluoroalcohols studied, the transfer constants increase with the increasing value of n. The results have been interpreted in terms of polar structure contribution in the transition state of the transfer reactions. 相似文献
6.
Y. H. Wen S. Lahiri Z. Qin X. L. Wu W. S. Liu 《Journal of Radioanalytical and Nuclear Chemistry》2002,253(2):263-265
An attempt has been made to develop a radiochemical methodology for the decontamination of a trace amount of radioactive cesium from a bulk amount of natural NaCl by liquid-liquid extraction (LLX). Open chain crown ethers, of amide type, namely, N,N,N",N"-tetraphenyl-3,6-dioxaoctanediamide (TDD), N,N,N",N"-tetraphenyl-3,6,9-trioxaundecanediamide and N,N"-dinaphthyl-N,N"-diphenyl-3,6-dioxaoctanediamide (DDD) have been chosen for this purpose. The separation factor between Cs and Na is the highest when 10-4M TDD dissolved in nitrobenzene is used as extractant and 0.4M picric acid at pH 5.0 is used as aqueous phase. About 60% Cs is extracted in this condition in a single run. 相似文献
7.
T. Datta Samanta S. Laskar D. Nayak S. Lahiri 《Journal of Radioanalytical and Nuclear Chemistry》2007,273(2):323-325
Binding ability of mercury, thallium, lead and bismuth with Erythrina variegata seed protein have been investigated using tracer packet technique. Due to the lack of standard methods, inter-comparisons
have been made among three different approaches, like trichloroacetic acid (TCA) precipitation, isoelectric precipitation
and dialysis of protein after incubation with the metals. Good agreement was observed for all the cases except that of lead. 相似文献
8.
The enthalpies of formation of the 2,2′-dipyridinium ion and the 2,2′-dipyridyl-iron(II) complex in methanol—water media at 25°C have been determined by caloriumetry. The entropy-changes have been calculated combining the enthalpy values with the corresponding free-energy changes previously reported. The role of solvents on the thermodynamic parameters has been discussed. 相似文献
9.
Bose G Nguyen VT Ullah E Lahiri S Görls H Langer P 《The Journal of organic chemistry》2004,69(26):9128-9134
The Lewis acid mediated domino "[3+3]-cyclization-homo-Michael" reaction of 1,3-bissilyl enol ethers with 1,1-diacylcyclopropanes allows an efficient one-pot synthesis of functionalized salicylates containing a halogenated side chain. A great variety of substitution patterns could be realized by variation of the starting materials and of the Lewis acid. The mechanism of the domino process was studied. 相似文献
10.