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381.
Kalyan Kali Sen Gupta Mrityunjoy Adhikari Shipra Sen Gupta 《Reaction Kinetics and Catalysis Letters》1989,38(2):313-318
The oxidation of ethanol by permanganate has been found to obey the rate law v=k[MeCHO][MnO
4
–
][H+]. The results are compared with those found for chromium (VI) oxidation of the same substrate.
V=k[MeCHO][MnO 4 – ][H+]. , (VI).相似文献
382.
A simple and rapid titrimetric method for estimation of fluorine in organic compounds and fluoropolymers is reported. It involves combustion of the sample in oxygen, absorption of the combustion products in an aqueous solution of Ce(III) nitrate and glycerol, containing hexamethylenetetramine, and finally titration with EDTA, with Xylenol Orange and Methylene Blue as screened indicator. 相似文献
383.
384.
Sobhan NiyogiBasudam Adhikari 《European Polymer Journal》2002,38(6):1237-1243
Two different polyimide semipermeable membranes have been prepared from two base polyimides of PMDA/ODA and BTDA/ODA by incorporation of lithium chloride with the respective poly(amic acids) and subsequently leaching out the maximum possible lithium chloride by water at slightly elevated temperature. The water and various organic vapor permeability of the lithium chloride modified films has been found to be better compared to the respective control films. BTDA/ODA based polyimide films show overall lower permeability. 相似文献
385.
Summary The reactions of four -diketonatoruthenium(III) complexes in the presence of HNO3 andp-MeC6H4SO3H in the 45° and 57° range were followed spectrophotometrically in Me2COH2O mixtures. Dissociation of Ru(acac)3 follows [H+]-dependent and [H+]2-dependent paths, whereas the bzac and F3acacF3 complexes follow only the [H+]-dependent path. The bzbz (Dibenzoylmethanate) complex is inert. Protonation of the bound ligand leads to its rupture from the metal ion. The bzac complex is kinetically more inert than the acac complex, because of extra stability arising from interaction of the (bzac) benzene ring with the pseudo-aromatic diketonate ring of the complex. Considering the kinetic labilities, the complexes may be arranged in the order Ru(F3acacF3)3>Ru(acac)3>Ru(bzac)3>Ru(bzbz)3.Activation parameters for [H+] dependent path are: H
1
86.5±7, 69±5, 121±7 kJ mol–1, S
2
–52±10, –107±10, 57±8 JK–1 mol–1 for acac, bzac and F3acacF3 complexes respectively and H
2
67±5 kJ mol–1, S
2
–92±8 JK–1 mol–1 for the acac complex only. 相似文献
386.
The reaction between K2[PtCl4] and a variety of tetraorganotin compounds SnMe3R (R = Me, aryl) in DMSO gives the complexes cis-[PtR2(DMSO)2] and trans-[PtR(Cl)(DMSO)2] in which the DMSO ligands are bound to Pt through S in the solid state. The DMSO ligands are easily displaced by a variety of N, P, As and Sb donors. 相似文献
387.
388.
I. Chakrabarty S. Adhikari B. S. Choudhury 《International Journal of Theoretical Physics》2007,46(10):2513-2515
In this letter, we show the impossibility of the general operation introduced by Pati (Phys. Rev. A 66:062319, 2002) using two different but consistent principles (i) no-signaling (ii) non increase of entanglement under LOCC. 相似文献
389.
390.
Accurate calculation of the moment of inertia of an irregular body is made difficult by the large number of quantities which
must be measured. A popular method is to use a trifilar suspension system to measure the period of oscillation of the body
in the horizontal plane. In this paper, some sources of error are discussed with particular attention given to the alignment
of the test object’s center of mass on the trifilar platform. The procedure is described, the necessary calculations are derived
and the relative importance of accuracy in different measurements is assesed. It is determined that the accurate alignment
of the centre of mass of the body being tested with the centre of the trifilar plate is insignificant compared to the accuracy
of the other measurements required in the calculations. 相似文献