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141.
142.
143.
Shekhar?KumarEmail author Pranay?Kumar?Sinha U.?Kamachi Mudali R.?Natarajan 《Journal of Radioanalytical and Nuclear Chemistry》2011,289(2):545-549
Formation and thermal decomposition of red-oil during unit operations of nuclear fuel cycle process flowsheets is a severe
risk. In the literature, red-oil formation has been investigated thoroughly in general and in detail after Tomsk-7 incident
on 6th April 1993. However there is no information on the thermal decomposition of formed red-oil. In this work, results of
unique experiments on adiabatic thermal decomposition of red-oil, red-oil equilibrated with excess of 4N nitric acid and 100%
TBP equilibrated with excess of 4N nitric acid have been discussed. 相似文献
144.
M.?Balamurugan Shekhar?KumarEmail author U.?Kamachi Mudali R.?Natarajan 《Journal of Radioanalytical and Nuclear Chemistry》2011,288(2):507-510
The cross sections for the 118Sn (n, α)115Cd, 120Sn (n, α)117gCd and 120Sn (n, α)117mCd reactions have been measured in the neutron energy range of 13.5–14.6 MeV using the activation technique and a coaxial
HPGe γ-ray detector. The fast neutrons were produced by the T (d, n) 4He reaction. The neutron energies in the measurements were determined by cross section ratios for 93Nb(n,2n)92mNb and 90Zr(n, 2n)89m+gZr reactions. The results of present work were discussed and compared with theoretical calculation data, measurement results
found in the literature and with the comprehensive evaluation data in ENDF/B-VII.0, CENDL-3.1, JENDL-4.0 libraries. 相似文献
145.
Bijendra Kumar M. Sampath Shekhar Kumar D. Sivakumar U. Kamachi Mudali R. Natarajan 《Journal of Radioanalytical and Nuclear Chemistry》2011,289(3):861-864
Recently authors demonstrated direct dissolution of g-level PHWR UO2 fuel pellet fragments and in situ extraction by TBP-HNO3 and TiAP-HNO3 solutions at atmospheric pressures. Extending the work, similar studies were performed on intact unirradiated PHWR UO2 fuel pellets (~15 g U) with varying compositions of organic solvate of tri-n-butyl phosphate (TBP). It was observed that extent of dissolution was a strong function of organic solution composition TBP·(HNO3)
x
(H2O)
y
. Complete dissolution of intact UO2 pellet in a reasonable time was observed only in case of a particular solvate composition. 相似文献
146.
Pranay Kumar Sinha Shekhar Kumar U. Kamachi Mudali R. Natarajan 《Journal of Radioanalytical and Nuclear Chemistry》2011,289(3):899-901
Phenyl trifluoromethyl sulfone (FS-13) is an inert diluent used in HCCD/PEG process for isolation and recovery of cesium and
strontium from highly radioactive raffinate waste. There is no experimental data available in open literature describing pressurization
due to the thermal decomposition of FS-13 at elevated temperatures. Experiments were conducted for determination of flash
point and heating of FS-13 under pressurized closed-vent conditions in an adiabatic calorimeter. During adiabatic experiments,
negligible pressurization was observed. 相似文献
147.
Mitta KavithaBodugam Mahipal Prathama S MainkarSrivari Chandrasekhar 《Tetrahedron letters》2011,52(14):1658-1662
N-Styryl triazoles are synthesized in one-pot starting with azido styrene obtained in situ from cinnamic acids and various acetylenes. 相似文献
148.
Chandrasekhar V Pandey MD Gopal K Azhakar R 《Dalton transactions (Cambridge, England : 2003)》2011,40(31):7873-7878
The reaction of the phosphorus trihydrazide, (S)P[N(Me)-NH(2)](3) (1) with quinoline-2-carboxaldehyde (C(9)H(6)N-2-CHO) in a 1:3 ratio afforded a trishydrazone, (S)P[N(Me)-N=CH-2-C(9)H(6)N](3) (2). Crystals of 2 were grown in three different solvent media affording an unsolvated (2, monoclinic, P2(1)/n) and two solvated (2·3H(2)O, trigonal, R3 and 2·2CH(3)OH, triclinic, P ?1) crystal forms. Each of these, while possessing an essentially similar molecular structure, adopt different crystal packing giving rise to supramolecular structures mediated by a variety of weak interactions: O-H-N, O-H-O, C-H-N, C-H-O, C-H-S, C-H-π, π-π, N-π and S-π. The reaction of 2 with Ag(ClO(4))(2)·6H(2)O in methanol afforded a dinuclear cationic cage [Ag{(S)P[N(Me)-N=CH-2-C(9)H(6)N](3)}·ClO(4)](2) (3). The molecular structure of 3 reveals a dimeric structure consisting of two Ag(I) ions that are held together by two ligands. Only two arms of the tris hydrazone ligand are involved in coordination while an unprecedented P=S→Ag(I) coordination is seen. This results in the formation of an Ag(2)S(2) dimer that is encapsulated by two trishydrazone ligands. Both compounds 2 and 3 are photoluminescent. 相似文献
149.
Raja DS Paramaguru G Bhuvanesh NS Reibenspies JH Renganathan R Natarajan K 《Dalton transactions (Cambridge, England : 2003)》2011,40(17):4548-4559
Four 2-oxo-1,2-dihydroquinoline-3-carbaldehyde N-substituted thiosemicarbazone ligands (H(2)-OQtsc-R, where R = H, Me, Et or Ph) and their corresponding new copper(II) complexes [CuCl(2)(H(2)-OQtsc-H)]·2H(2)O (1), [CuCl(2)(H(2)-OQtsc-Me)]·2H(2)O (2), [CuCl(2)(H(2)-OQtsc-Et)(CH(3)OH)]Cl (3) and [CuCl(H-OQtsc-Ph)]·CH(3)OH (4) have been synthesized in order to correlate the effect of terminal N-substitution on coordination behaviour, structure and biological activity. Single crystal X-ray diffraction studies revealed that the complexes 1, 2 and 3 have square pyramidal geometry around the central metal ion. In the complexes 1 and 2, the copper ion is coordinated by the ligand with ONS donor atoms, one chloride ion in apical position and the other chloride in the basal plane. Complex 3 consists of [CuCl(2)(H(2)-OQtsc-Et)(CH(3)OH)](+) cation and a chloride as counter ion. The copper ion is coordinated by the ligand with ONS donor atoms and by one chloride ion in the basal plane. One methanol molecule is bonded through its neutral oxygen in the apical position. Complex 4 is square planar with the ligand coordinating through uni-negative tridentate ONS(-) and by one chloride ion in the basal plane. The binding of complexes with lysozyme protein was carried out by fluorescence spectroscopy. Investigations of antioxidation properties showed that all the copper(II) complexes have strong radical scavenging properties. The cytotoxicity of the complexes 3 and 4 against NIH 3T3 and HeLa cell lines showed that synergy between the metal and ligands results in a significant enhancement in the cell death with IC(50) of ~10-40 μM. A size dependence of substitution at terminal N in the thiosemicarbazones on the biological activities of the complexes has been observed. 相似文献
150.
Kumar A Lal Tamta M Negi N Chandrasekhar K Singh Negi D 《Natural product research》2011,25(18):1680-1686
The essential oil of Premna latifolia Roxb. was obtained by hydrodistillation of fresh leaves of the plant having an oil yield of 0.05%, both non-polar and essential oil were analysed by GC and GC-MS. Hexane fraction of the leaves of P. latifolia was transesterified and analysed by GC and GC-MS, 40 non-polar components were identified comprising 89.3%. The most abundant fatty acid constituents were hexadecanoic acid (25.04%), 8,11,14-docosatrienoic acid (13.62%), octadecanoic acid (6.82%), 9,12-octadecadienoic acid (4.19%) and 29 components were investigated in the essential oil which comprises 78.1%. The most abundant oil constituents were 1-octen-3-ol (35.69%), terpendiol II (7.19%), δ-guaiene (7.49%) 2-undecanone (4.80%) and α-pinene (3.27%). Different extracts were also tested against polyphagous crop pest Spodoptera litura for antifeedant activity. Essential oil showed maximum growth reduction of 56.83% followed by chloroform extract of 43.93%. 相似文献