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991.
The effect of the promoter and micellar catalyst on chromic acid on the oxidation of ethanol in aqueous acid media has been studied. Picolinic acid (PA), 1,10‐phenanthroline (phen), and 2,2′‐bipyridine (bipy) are used as promoters. Sodium dodecyl sulfate (SDS), cetyl pyridinium chloride (CPC), and Triton‐X‐100 (TX‐100) are tested as micellar catalysts. Hexavelent chromium is an active species in the absence of the promoter. In the presence of the heteroaromatic nitrogen bases used as the promoter, Cr(VI)–PA, Cr(VI)–bipy, and Cr(VI)–phen complexes have been proposed as the active oxidants. The time taken for completion of the reaction using different combinations of promoter and micellar catalysts are different. Although the rate is highest (12.5 times) in TX‐100 in the absence of the promoter, it is observed that the rate is almost 737 times faster for the combination of SDS and bipy compared to the unpromoted and uncatalyzed path. CPC inhibits the oxidation process. The observed acceleration and retardation of the rate of oxidation process has been explained on the basis of partitioning of the reactants in the micellar and aqueous phase. © 2013 Wiley Periodicals, Inc. Int J Chem Kinet 45: 175–186, 2013  相似文献   
992.
6-Aminosaccharin and related monomers were subjected to polymerization as melts and in solvents. The products from these studies passed through soluble, hemipolymer stages corresponding to polyamide structures before being cyclized at higher temperatures to the final, insoluble, thermally stable polymers. Melt polymerization of 6-aminosaccharin as the triethylamine salt was the preferred procedure and yielded products of highest intrinsic viscosity (0.431 dl/g in N,N-dimethylacetamide).  相似文献   
993.
994.
Structural Chemistry - Using a social self-sorting phenomenon, two Pt(II)←pyridyl, carboxylate heteroleptic metallacages cage 1 and cage 2 have been constructed in nearly quantitative yields...  相似文献   
995.
Ray  Anirban  Saha  D. C.  Saha  Papri  Chowdhury  A. Roy 《Nonlinear dynamics》2017,87(2):1393-1404
Nonlinear Dynamics - Third-order nonlinear dynamical systems with attractors (one with no fixed point and the other with a stable fixed point) are conjugately coupled. It is observed that the...  相似文献   
996.
Structural Chemistry - To evaluate the sensing ability of poly(3,4-ethylenedioxythiophene) (PEDOT) towards CO2 and SO2 gaseous molecules, an extensive quantum mechanical study has been carried out...  相似文献   
997.
The work demonstrated the microstructure and the relaxation behavior of flexible electroactive blends of poly(vinylidene fluoride) (PVDF)/hydrogenated nitrile rubber (HNBR) by small‐angle X‐ray scattering and dielectric relaxation spectroscopy. Very few studies have been done so far on this topic for crystalline/rubbery blends. Lamellar morphology was observed for both the PVDF and its blends. HNBR suppressed the mobility of PVDF above its melting temperature, as evident from lowering of crystallization temperature, due to physical interaction. The interaction was increased with HNBR content. However, after complete crystallization, HNBR segments were expelled out from the lamella, and crystal long period remained intact in all the blends. Interestingly, some HNBR segments remained in the amorphous part of PVDF which reduced the electron density contrast of its crystalline and amorphous region. When HNBR was crosslinked, the interaction was reduced, and consequently, the crystallization became faster and electron density contrast increased. From the microscopic study, polydispersed particles were observed within the crystalline lamella. Interfacial polarization (IP) relaxation of PVDF was absent in the blends due to physical interaction, whereas IP relaxation of HNBR shifted to a higher frequency. The shift was higher at higher HNBR content and decreased when HNBR was crosslinked. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57, 851–866  相似文献   
998.
In this work, we demonstrate a simple, one pot and seed free synthetic route for the formation of gold nanorods (Au NRs) via thermal decomposition of gold(I) dithiophosphate {[Au2{S2P(OiPr)2}2]n,} 1 complex as a molecular precursor in presence of 4′‐amino‐biphenyl‐4‐carboxylic molecule. Here [Au2{S2P(OiPr)2}2]n, complex functioned as gold (Au) source and 4′‐amino‐biphenyl‐4‐carboxylic molecule stabilized gold (Au) nanorods (NRs) through the unidirectional coating of Au surface during its growth in the reaction medium.  相似文献   
999.
In this work, we examine two algorithm schemes, namely, Kudryashov expansion andAuxiliary equation method for obtaining new optical soliton solutions of the discreteelectrical lattice models in nonlinear scheme (Salerno equation). Our solutions obtainedhere are include the hyperbolic, rational, and trigonometric functions. Our two used methods are proved to be effective and powerful methods in obtaining the exact solutions of nonlinearevolution equations (NLEEs).  相似文献   
1000.
Research on Chemical Intermediates - A highly convenient method has been developed for the synthesis of 2-(ethynyloxy) napthaene-1-carbaldehyde and its derivatives. Substituted naphthalene...  相似文献   
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