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611.
A.?Bhattacharyya P.?K.?Mohapatra T.?Gadly S.?K.?Ghosh D.?R.?Raut V.?K.?ManchandaEmail author 《Journal of Radioanalytical and Nuclear Chemistry》2011,288(2):571-577
Ethyl-substituted bis-triazinylpyridine (Et-BTP), a nitrogen containing soft-donor extractant, was used in investigations
pertaining to the separation of Am3+ and Eu3+ from dilute nitric acid feed solutions by extraction chromatography using XAD-4 as the inert support, chlorinated dicarbollide
as the modifier and 2-nitrophenyloctylether (NPOE) as the diluent. After carrying out a series of experiments, the optimum
composition of the extractant mixture for the resin was found out to be 0.1 M Et-BTP and 0.025 M CCD in NPOE. Separation factor
values were encouraging to carry out subsequent batch uptake studies at varying nitrate ion concentration which indicated
favourable separation behaviour up to NaNO3 concentration of 2 M. Column studies have been carried out and conditions for elution and separation of Am3+ from Eu3+ have been found out. Long term stability of the resin was also investigated. 相似文献
612.
Electric field gradient inhcp transition metal scandium has been calculated as the sum of contributions from lattice ions and conduction electrons. For
the lattice contributionq
latt, a point-charge model has been assumed. The contribution from conduction electronsq
el, on the other hand, has been evaluated by carrying out an energy-band calculation using non-local transition-metal model
potential. The results obtained are:q
el=−106.11×1013 esu/cm3 andq
latt=122.17×1013 esu/cm3. The net field gradient (q
el+q
latt) of 16.06×1013 esu/cm3 agrees quite well with the experimental result, |q
expt|=13×1013 esu/cm3. Directions of further improvement in the theory are discussed. 相似文献
613.
R. B. Gujar S. A. Ansari A. Bhattacharyya P. K. Mohapatra A. S. Kanekar P. N. Pathak V. K. Manchanda 《Journal of Radioanalytical and Nuclear Chemistry》2011,288(2):621-627
The radiolytic stability of a branched diglycolamide extractant, namely N,N,N′,N′-tetra-2-ethylhexyl diglycolamide (T2EHDGA) dissolved in n-dodecane containing several phase modifiers, viz. N,N-dihexyloctanamide (DHOA), tri-n-butyl phosphate (TBP), 1-decanol and iso-decanol has been investigated. The distribution ratio of Am(III) decreased with
increased radiation dose studied up to 1000 kGy. Nevertheless, all the composition of extractants showed satisfactory results
up to 500 kGy, beyond which the extractants degraded drastically. The stripping behaviour of Am(III) with 0.2 M HNO3 was found to be unaffected even with the ligand solution irradiated up to 1000 kGy. Extraction of fission product and structural
elements was also investigated using the irradiated solvents and was found to be not significantly affected with increasing
absorbed dose with the exception of Mo which showed sharp rise in the distribution coefficient values. Loading of Nd in the
organic phase decreased with the irradiated solvent due to degradation of the carrier. The effect of the absorbed dose on
physical parameters such as density, viscosity and interfacial tension of the solvents has also been investigated. 相似文献
614.
The interaction of submicellar concentrations of various physiologically important unconjugated [sodium deoxycholate (NaDC), sodium cholate (NaC)] and conjugated [sodium glycodeoxycholate (NaGDC), sodium glycocholate (NaGC), sodium taurodeoxycholate (NaTDC), sodium taurocholate (NaTC)] bile salts with dipalmitoylphosphatidylcholine (DPPC) and dimyristoylphosphatidylcholine (DMPC) small unilamellar vesicles in solid gel (SG) and liquid crystalline (LC) phases was investigated using the excited-state prototropism of 1-naphthol. Steady-state and time-resolved fluorescence of the two excited-state prototropic forms of 1-naphthol indicate that submicellar bile salt concentration induces hydration of the lipid bilayer membrane into the core region. This hydration effect is a general phenomenon of the bile salts studied. The bilayer hydration efficiency of the bile salt follows the order NaDC > NaC > NaGDC > NaTDC > NaGC > NaTC for both DPPC and DMPC vesicles in their SG and LC phases. 相似文献
615.
An analytical approximation for the similarity solutions of the two- and three-dimensional stagnation slip flow and heat transfer
is obtained by using the homotopy analysis method. This method is a series expansion method, but it is different from the
perturbation technique, because it is independent of small physical parameters at all. Instead, it is based on a continuous
mapping in topology so that it is applicable for not only weakly but also strongly nonlinear flow phenomena. Convergent [m,m] homotopy Padé approximants are obtained and compared with the numerical results and the asymptotic approximations. It is
found that the homotopy Padé approximants agree well with the numerical results. The effects of the slip length ℓ and the thermal slip constant β on the heat transfer characteristics are investigated and discussed.
Supported by the National Natural Science Foundation of China (Grant No. 10872129) 相似文献
616.
The Bloch enhancement factor α(k
f
) of the electric field gradient has been evaluated for the half-filledd-core Fe host metal and completely filledd-core Cu host metal in single orthogonalized plane wave (OPW) approximation. For this purpose the radially-dependent antishielding
factors,γ(r) have been calculated in non-orthogonal Hartree-Fock perturbation theory (NHFPT). The results show that the contributions
of antishielding to α(k
f
) from the plane wave-plane wave part and the core part of the OPW state are individually large but opposite in sign and thereby
lead to partial cancellation. The net effect of antishielding on α(k
f
) is found to be − 5.6% in Fe and 14% in Cu. 相似文献
617.
Dhabaleswar Mohapatra Snehashish Chakraverty 《Mathematical Methods in the Applied Sciences》2023,46(1):840-866
In this paper, a new method is proposed to solve type-2 fuzzy linear system of equations by converting the system into three interval linear systems and one crisp linear system of equations. In this work, three possible cases of type-2 fuzzy linear system is considered depending upon uncertainty (as type-2 fuzzy number) in right-hand side vector , in co-efficient matrix , and both in co-efficient matrix as well as right-hand side vector . Triangular perfect quasi type-2 fuzzy numbers are taken to propose the new method. The main significance of the proposed method is that it uses the arithmetic of interval theory, which makes this method easier to handle. Five numerical examples are solved to show the validation of the proposed technique. Further, two application problems related to 6-bar truss and rectangular sheet are encountered in type-2 fuzzy environment. Comparison among the results obtained by the present method and previously achieved results is also made in this work, which shows that the results are close enough and, in some cases, better bounds for the solution are obtained. 相似文献
618.
Generalizations of fractional integral inequalities were introduced by many authors. The aim of our investigation is to establish some new fractional integral inequalities using Marichev–Saigo–Maeda (MSM) fractional integral operator for convex function. Further, we obtain some more fractional integral inequalities of Grüss type using MSM operator. 相似文献
619.