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101.
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103.
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
104.
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
105.
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
106.
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
107.
Specificity analysis-based identification of new methylation targets of the SET7/9 protein lysine methyltransferase 总被引:1,自引:0,他引:1
We applied peptide array methylation to determine an optimized target sequence for the SET7/9 (KMT7) protein lysine methyltransferase. Based on this, we identified 91 new peptide substrates from human proteins, many of them better than known substrates. We confirmed methylation of corresponding protein domains in?vitro and in?vivo with a high success rate for strongly methylated peptides and showed methylation of nine nonhistone proteins (AKA6, CENPC1, MeCP2, MINT, PPARBP, ZDH8, Cullin1, IRF1, and [weakly] TTK) and of H2A and H2B, which more than doubles the number of known SET7/9 targets. SET7/9 is inhibited by phosphorylation of histone and nonhistone substrate proteins. One lysine in the MINT protein is dimethylated in?vitro and in?vivo demonstrating that the product pattern created by SET7/9 depends on the amino acid sequence context of the target site. 相似文献
108.
The size, shape and controlled dispersity of nanoparticles play a vital role in determining the physical, chemical, optical and electronic properties attributing its applications in environmental, biotechnological and biomedical fields. Various physical and chemical processes have been exploited in the synthesis of several inorganic metal nanoparticles by wet and dry approaches viz., ultraviolet irradiation, aerosol technologies, lithography, laser ablation, ultrasonic fields, and photochemical reduction techniques. However, these methodologies remain expensive and involve the use of hazardous chemicals. Therefore, there is a growing concern for the development of alternative environment friendly and sustainable methods. Increasing awareness towards green chemistry and biological processes has led to a necessity to develop simple, cost-effective and eco-friendly procedures. Phototrophic eukaryotes such as plants, algae, and diatoms and heterotrophic human cell lines and some biocompatible agents have been reported to synthesize greener nanoparticles like cobalt, copper, silver, gold, bimetallic alloys, silica, palladium, platinum, iridium, magnetite and quantum dots. Owing to the diversity and sustainability, the use of phototrophic and heterotrophic eukaryotes and biocompatible agents for the synthesis of nanomaterials is yet to be fully explored. This review describes the recent advancements in the green synthesis and applications of metal nanoparticles by plants, aquatic autotrophs, human cell lines, biocompatible agents and biomolecules. 相似文献
109.
N(2)-alkyl analogues of 8-oxo-7,8-dihydro-2'-deoxyguanosine (OG) were synthesized (alkyl = propyl, benzyl) via reductive amination of the protected OG nucleoside and incorporated into various positions of an RNA strand. Thermal stability studies of duplexes containing A or C opposite a single modified base revealed only moderate destabilization. Both OG as well as its N(2)-alkyl analogues can pair opposite A or C with nearly equal stability, potentially offering a new means of modulating RNA-protein interactions in the minor vs major grooves. 相似文献
110.