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101.
Sundararajan M Sinha V Bandyopadhyay T Ghosh SK 《The journal of physical chemistry. A》2012,116(17):4388-4395
The feasibility of using cucurbituril host molecule as a probable actinyl cation binders candidate is investigated through density functional theory based calculations. Various possible binding sites of the cucurbit[5]uril host molecule to uranyl are analyzed and based on the binding energy evaluations, μ(5)-binding is predicted to be favored. For this coordination, the structure, vibrational spectra, and binding energies are evaluated for the binding of three actinyls in hexa-valent and penta-valent oxidation states with functionalized cucurbiturils. Functionalizing cucurbituril with methyl and cyclohexyl groups increases the binding affinities of actinyls, whereas fluorination decreases the binding affinities as compared to the native host molecule. Surprisingly hydroxylation of the host molecule does not distinguish the oxidation state of the three actinyls. 相似文献
102.
Data reconciliation considers the restoration of mass balance among the noise prone measured data by way of component adjustments for the various particle size or particle density classes or assays over the separating node. In this paper, the method of Lagrange multipliers has been extended to balance bivariate feed and product size-density distributions of coal particles split from a settling column. The settling suspension in the column was split into two product fractions at 40% height from the bottom after a minute settling of homogenized suspension at start. Reconciliation of data assists to estimate solid flow split of particles to the settled stream as well as helps to calculate the profiles of partition curves of the marginal particle size or particle density distributions. In general, Lagrange multiplier method with uniform weighting of its components may not guarantee a smooth partition surface and thus the reconciled data needs further refinement to establish the nature of the surface. In order to overcome this difficulty, a simple alternative method of reconciling bivariate size-density data using partition surface concept is explored in this paper. 相似文献
103.
Vivek M. Wasekar 《Heat and Mass Transfer》2009,45(11):1409-1414
Variation in degree of surface wettability is presented through the application of Cooper’s correlative approach (h ∝ M
−0.5
q
w
″0.67) for computing enhancement (ϕ) in nucleate pool boiling of aqueous solutions of SDS and Triton X-100 and its presentation with Marangoni parameter (χ) that represents the dynamic convection effects due to surface tension gradients. Dynamic spreading coefficient defined as
σ
dyn
N
a
, which relates spreading and wetting characteristics with the active nucleation site density on the heated surface and bubble
evolution process, represents cavity filling and activation process and eliminates the concentration dependence of nucleate
pool boiling heat transfer in boiling of aqueous surfactant solutions. Using the dynamic spreading coefficient (σ
dyn
N
a
= 0.09q
w
″0.71), correlation predictions within ±15% for both SDS and Triton X-100 solutions for low heat flux boiling condition (q
w″ ≤ 100 kW/m2) characterised primarily by isolated bubble regime are presented. 相似文献
104.
We have studied the dynamics of non-colloidal short fiber suspensions in bounded shear flow using the Stokesian dynamics simulation. Such particles make up the microstructure of many suspensions for which the macroscopic dynamics are not well understood. The effect of wall on the fiber dynamics is the main focus of this work. For a single fiber undergoing simple shear flow between plane parallel walls the period of rotation was compared with the Jeffrey’s orbit. A fiber placed close to the wall shows significant deviation from Jeffrey’s orbit. The fiber moving near a solid wall in bounded shear flow follows a pole-vaulting motion, and its centroid location from the wall is also periodic. Simulations were also carried out to study the effect of fiber–fiber interactions on the viscosity of concentrated suspensions. 相似文献
105.
K.M. Prabhu Kumar B.C. Vasantha Kumar P. Raghavendra Kumar Ray J. Butcher H.K. Vivek P.A. Suchetan H.D. Revanasiddappa Sabine Foro 《应用有机金属化学》2020,34(6):e5634
A novel selenated Schiff base (S) -L 1 H has been synthesized from (2S)-1-(benzylselanyl)-3-phenylpropan-2-amine which upon reduction formed a reduced Schiff base (S) -L 2 H . Palladium (II) complexes (S) -1 and (S) -2 of ligands (S) -L 1 H and (S) -L 2 H respectively were successfully synthesized. The structures of all four compounds were thoroughly identified by analytical and various spectroscopic techniques. The absolute molecular structures of the above two complexes were further confirmed by single crystal X-ray diffraction. Both (S) -L 1 H and (S) -L 2 H coordinated as monobasic ((S) -L 1–2 ), chelating, tridentate (Se,N,O−) ligands resulting in the complexes of composition (S) - [PdCl( L 1/2 )] [(S) -1/2 ]. In the crystals of complexes (S) -1 and (S) -2 , there were moderate to strong Se⋯O, CH⋯Cl and CH⋯O types of intermolecular secondary interactions. CT-DNA binding activity of these selenium-containing ligands and their palladium complexes bearing a Pd–Se bond have been evaluated for the first time by performing electronic absorption titration and fluorescence emission quenching using CT-DNA-EB and viscometric experiments. These ligands and complexes exhibited remarkable DNA binding activity as shown by their intrinsic DNA binding constants (Kb) and Stern–Volmer constants (Ksv) in the ranges 5.2–9.9 × 104 and 3.6–4.7 × 104, respectively. The viscosity of CT-DNA decreases with increasing concentration of these compounds. The results of the DNA-binding studies revealed that all of the compounds interact with DNA at a minor groove which was further confirmed by molecular docking studies. 相似文献
106.
Physics of Atomic Nuclei - Neutrino oscillation is an experimentally established phenomenon by which neutrinos undergo flavor transformations periodically as they propagate large enough distances.... 相似文献
107.
Vivek PolshettiwarManisha Nivsarkar Jyotiranjan AcharyaM.P Kaushik 《Tetrahedron letters》2003,44(5):887-889
Benzyltriethylammonium tetracosathioheptamolybdate [(C6H5CH2N(Et)3)6Mo7S24] has been found to be a superior sulfur transfer reagent for the conversion of alkyl halides to the corresponding disulfides in excellent yields under very mild reaction conditions. 相似文献
108.
An averaged system to approximate the slow dynamics of a two timescale nonlinear stochastic control system is introduced.
Validity of the approximation is established. Special cases are considered to illustrate the general theory. 相似文献
109.
In this note a dual problem is formulated for a given class of disjunctive linear fractional programming problems. This result generalizes to fractional programming the duality theorem of disjunctive linear programming originated by Balas. Two examples are given to illustrate the result. 相似文献
110.
Silica-supported Pd catalysts for Heck coupling reactions 总被引:1,自引:0,他引:1