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21.
I. C. Pius M. M. Charyulu C. K. Sivaramakrishnan S. K. Patil 《Journal of Radioanalytical and Nuclear Chemistry》1994,186(5):385-392
The extraction of Pu(IV) from oxalic acid-nitric acid mixtures has been investigated using a liquid anion exchanger, Aliquat-336, in xylene. The presence of oxalic acid is known to have adverse effects on the extraction of Pu(IV) by Aliquat-336. The use of cations, Al(III), Fe(III) or Zr(IV) was explored to overcome the effect of oxalic acid on Pu(IV) extraction. The data obtained reveal that Pu(IV) is quantitatively extracted by Aliquat-336, even in the presence of oxalic acid, when Al(III), Fe(III) or Zr(IV) is added. The extracted Pu(IV) can be back-extracted using aqueous ammonium carbonate. 相似文献
22.
On the Temperature Dependence of the 13C-NMR. Spectra of [5-6-η-(1Z,5E)-Cyclooctadien] and of (lZ, 5E)-Cyclooctadiene The activation parameters of the conformational ring inversion process (simultaneous rotation around the C(3), C(4) and C(7), C(8) bonds; cf. Scheme 1) of the title compounds ( 1 and 2 , respectively) have been determined between 275 L and 155 K by a complete line shape analysis of the temperature dependent proton noise-modulated decoupled 13C-NMR. spectra of 1 and 2 . The temperature dependence of the rates (k( 1 ) and k( 2 ), respectively) of the inversion process can be described by the following equations (no influence of the solvents was observed; Ea in J/mol): . Further data are given in Tables 1 and 2. The carbonyl groups of the complex 1 show at 180 K , where the ring inversion process is frozen out, a single line at 211 ppm, i. e. the coalescence temperature of the carbonyl groups must be < 180 K . 相似文献
23.
M. M. Charyulu I. C. Pius A. Kadam M. Ray C. K. Sivaramakrishnan S. K. Patil 《Journal of Radioanalytical and Nuclear Chemistry》1991,152(2):479-486
Behaviour of Pu(IV) and Pu(VI) in basic media has been investigated by studying their stabilities and quantitative determination by spectrophotometry. Beer's law was found to be obeyed in the range of 1·10–3 to 5·10–3 M Pu(IV) at 485 nm peak with a molar absorption coefficient of 95M–1· cm–1 in sodium carbonate medium. In case of Pu(VI), in the same medium Beer's law was obeyed in the concentration range of 2·10–3 to 1·10–2M at 550 nm with a molar absorption coefficient of 50M–1·cm–1. Distribution ratios of Pu(IV) and Pu(VI) for their sorption on Al2O3 and Amberlyst A-26 (MP) resin from bicarbonate and carbonate media have been determined. High distribution ratios obtained indicate the feasibility of decreasing the plutonium content of basic carbonate streams in reprocessing. 10% breakthrough capacities for Pu(IV) and Pu(VI) with these exchangers during column operations have also been determined. 相似文献
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26.
N. S. Prostakov L. A. Gaivoronskaya G. Alvarado Urbina Pius D. Emeruva Tirio Nakanisi 《Chemistry of Heterocyclic Compounds》1972,8(5):604-606
Two isomers of 3-methylindano[2,1-c]piperidine were isolated in the reduction of 3-methyl-2-azafluorene with sodium in alcohol. N-(-Hydroxyalkyl) derivatives of this heterocyclic system were obtainedTranslated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 666–668, May, 1972. 相似文献
27.
Badertscher M Bischofberger K Munk ME Pretsch E 《Journal of chemical information and computer sciences》2001,41(4):889-893
The existing formalism to calculate the degree of unsaturation from the molecular formula of organic molecules cannot be applied to charged and/or disconnected species. Moreover, the calculated value depends on the assumed formal valence of each of the elements. In this work, we introduce a new formalism that eliminates these problems. The suggested property, degree of unsaturation, can be calculated from the molecular formula as well as from any structural representation of a molecule corresponding to that molecular formula. 相似文献
28.
Won E Ko BR Adachi I Aihara H Arinstein K Asner DM Aushev T Bakich AM Barberio E Bay A Bhardwaj V Bhuyan B Bischofberger M Bondar A Bozek A Bračko M Brodzicka J Browder TE Chang P Chen A Chen P Cheon BG Chilikin K Cho IS Cho K Choi SK Choi Y Dalseno J Danilov M Doležal Z Drásal Z Drutskoy A Eidelman S Fast JE Gaur V Gabyshev N Garmash A Goh YM Golob B Haba J Hara T Hayasaka K Hayashii H Horii Y Hoshi Y Hou WS Hsiung YB Hyun HJ Iijima T Inami K Ishikawa A Itoh R Iwabuchi M Iwasaki Y Iwashita T 《Physical review letters》2011,107(22):221801
We report the first observation of the doubly Cabibbo-suppressed decays D(+)→K(+)η((')) using a 791 fb(-1) data sample collected with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. The ratio of the branching fractions of doubly Cabibbo-suppressed relative to singly Cabibbo-suppressed D(+)→π(+)η((')) decays are B(D(+)→K(+)η)/B(D(+)→π(+)η)=(3.06±0.43±0.14)% and B(D(+)→K(+)η')/B(D(+)→π(+)η')=(3.77±0.39±0.10)%. From these, we find that the relative final-state phase difference between the tree and annihilation amplitudes in D(+) decays, δ(TA), is (72±9)° or (288±9)°. We also report the most precise measurements of CP asymmetries to date: A(CP)(D(+)→π(+)η)=(+1.74±1.13±0.19)% and A(CP)(D(+)→π(+)η')=(-0.12±1.12±0.17)%. 相似文献
29.
30.
Kavitha Jayachandran R. D. Bhanushali I. C. Pius S. K. Mukerjee 《Journal of Radioanalytical and Nuclear Chemistry》2008,278(1):103-109
Synthetic inorganic exchangers exhibit good thermal and radiation stability. Thorium oxalate precipitate shows potential for
co-precipitation of plutonium and americium from oxalate supernatant generated during plutonium oxalate precipitation. In
the present study, efforts were made to prepare thorium oxalate precipitate to be used for column operation. Distribution
ratios were determined to optimize conditions for sorption of plutonium and americium on thorium oxalate from nitric acid
+ oxalic acid solutions with composition similar to that of oxalate supernatant. Column experiments were also performed to
evaluate the sorption capacity of thorium oxalate for plutonium and americium from the same medium. The result showed that,
thorium oxalate prepared in 1.75M HNO3 at 70 °C is suitable for column operations. These studies showed that plutonium and americium could be simultaneously removed
from aqueous solutions with composition similar to plutonium oxalate waste using glass column packed with thorium oxalate
and these nuclides could be recovered by eluting with 3M HNO3. 相似文献