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Kaushik Dutta Munia Mukherjee A. S. Brar 《Journal of polymer science. Part A, Polymer chemistry》1999,37(5):551-556
Poly(vinyl acetate) (PVA) prepared by photopolymerization was studied by a combination of one and two dimensional NMR spectroscopy. The 13C{1H} and 1H NMR spectra of the homopolymer (PVA) were assigned to the configurational pentads (CH region) and tetrads (CH2 region). These assignments were substantiated by the use of two dimensional heteronuclear single quantum correlation (HSQC), heteronuclear single quantum correlation‐total correlation spectroscopy (HSQC‐TOCSY) and double quantum filtered correlation spectroscopy (DQFCOSY) experiments. The results obtained by the analysis of the area under the resonance signals confirmed that PVA obeys Bernoullian statistics. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 551–556, 1999 相似文献
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A. S. Brar Kaushik Dutta S. K. Hekmatyar 《Journal of polymer science. Part A, Polymer chemistry》1998,36(7):1081-1092
The acrylonitrile/methyl methacrylate copolymers of different monomer concentration were prepared by photo polymerization using uranyl ion as initiator. The carbon 13 and proton spectra of these copolymers are overlapping and complex. The complete spectral assignment of the 13C- and 1H-NMR spectra were done with the help of Distortionless Enhancement by Polarization Transfer (DEPT) and two dimensional 13C–1H Heteronuclear Single Quantum Correlation (HSQC) experiments. The methylene, methine and the methyl carbon resonances show both stereochemical (triad level) and compositional (dyad, triad, tetrad, pentad and hexad level) sensitivity. 2D Double Quantum Filtered Correlated Spectroscopy (DQFCOSY) experiment was used to ascertain the various geminal couplings between the methylene protons. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1081–1092, 1998 相似文献
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Himadri Tanaya Das Elango Balaji T Subhashree Mohapatra Swapnamoy Dutta Nigamananda Das Mohammed A. Assiri 《Chemical record (New York, N.Y.)》2024,24(1):e202300226
In the recent times research towards solid state supercapacitors (SSS) have increased drastically due to the promising performance in futuristic technologies particularly in portable and flexible electronics like smart watches, smart fabrics, foldable smartphones and tablets. Also, when compared to supercapacitors using liquid electrolyte, solid electrolyte has several advantages like high energy density, safety, high cycle life, flexible form factor, and less environmental impact. The crucial factor determining the sustainability of a technology is the eco-friendliness since the natural resources are being exploited in a wide scale. Numerous studies have focused on biodegradable materials for supercapacitor electrodes, electrolytes, and other inactive components. Making use of these biodegradable materials to design a SSS enables the technology to sustain for a very long time since biodegradable materials are not only environment friendly but also, they show relatively high performance. This review focuses on recent progress of different biodegradable electrodes, and electrolytes along with their properties, electrochemical performance and biodegradable capabilities for SSS have been analyzed and provides a concise summary enabling readers to understand the importance of biodegradable materials and to narrow down the research in a more rational way. 相似文献
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Amit Basak Subhendu Sekhar Bag Kakali Rani Rudra Jharna Barman Sumana Dutta 《ChemInform》2002,33(48):115-115
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A nonlinear vibration isolator is considered to study effectiveness of isolation against harmonic force and displacement excitations. Nonlinearity in the magneto-rheological (MR) fluid based damper as well as in the elastic member is taken into account. The MR-damper has been modeled including Bouc–Wen hysteretic element and the spring is taken to have cubic nonlinearity. Analytical expression for the energy dissipation characteristics of the damper has been derived. Near resonant response of the isolated mass is obtained by a modified averaging technique suitable for hysteretic type nonlinearity present in the system. The performance of the isolators is estimated for various nonlinear stiffness values, both hardening and softening types. Different performance measures are also proposed to judge the performance of the nonlinear isolator. 相似文献
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In this article we discuss the conditions required to guarantee the non-emptiness and the boundedness of certain subsets of the set of Lagrange multipliers for an inequality and equality constrained vector minimization problem. 相似文献