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排序方式: 共有397条查询结果,搜索用时 15 毫秒
1.
T. Brian Cavitt Brian Phillips Charles E. Hoyle Bo Pan Sukhendu B. Hait Kalyanaraman Viswanathan Sonny Jnsson 《Journal of polymer science. Part A, Polymer chemistry》2004,42(16):4009-4015
Three‐component photoinitiators comprised of an N‐arylphthalimide, a diarylketone, and a tertiary amine were investigated for their initiation efficiency of acrylate polymerization. The use of an electron‐deficient N‐arylphthalimide resulted in a greater acrylate polymerization rate than an electron‐rich N‐arylphthalimide. Triplet energies of each N‐arylphthalimide, determined from their phosphorescence spectra, and the respective rate constants for triplet quenching by the N‐arylphthalimide derivatives (acquired via laser flash photolysis) indicated that an electron–proton transfer from an intermediate radical species to the N‐arylphthalimide (not energy transfer from triplet sensitization) is responsible for generating the initiating radicals under the conditions and species concentrations used for polymerization. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4009–4015, 2004 相似文献
2.
Prior studies have shown that inventories in a one vendor, multi-buyer supply chain with deterministic demands can be coordinated effectively through the use of common replenishment epochs (CRE). In this paper, we study the impact of demand uncertainty on the effectiveness of coordinating such a supply chain. We develop a model to analyse the coordination mechanism using CRE in a one-vendor, multi-buyer supply chain, when the demand faced by the buyers is stochastic. Our numerical study based on the model found that coordination through CRE may not always be beneficial when the demand variance is high. We also investigate a strategy of advance order processing by the vendor to improve the effectiveness of coordination through CRE. 相似文献
3.
S. Balasubrahmanyam B. Viswanathan V. R. S. Rao J. C. Kuriacose 《Journal of Radioanalytical and Nuclear Chemistry》1985,96(3):301-309
The effect of60Co -radiation on La2CuO4 solid catalyst prepared by the ceramic method has been studied. Gamma irradiation of La2CuO4 samples has been found to increase the Cu+ content, electrical conductivities and decrease the magnetic susceptibilities of the catalyst. The results have been interpreted on the basis of the crystal field model of the structure of La2CuO4. 相似文献
4.
Kavitha V Sundararajan K Viswanathan KS 《The journal of physical chemistry. A》2005,109(41):9259-9264
Conformations of trimethoxymethylsilane were studied using matrix isolation infrared spectroscopy and ab initio computations. Trimethoxymethylsilane was trapped in both argon and nitrogen matrixes using heated nozzle effusive sources and a supersonic jet source, in an effort to alter the conformational population in the matrix. Ab initio calculations were carried out at the HF and B3LYP level using 6-31++G basis set to support our experimental observations. The frequencies computed at the B3LYP level was found to fit well with our experimental data. A conformer with a C1(g(+/-)g(+/-)t) structure was predicted by our computations to be the ground state conformer. 相似文献
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J. Tellinghuisen P. Berwanger J.G. Ashmore K.S. Viswanathan 《Chemical physics letters》1981,84(3):528-533
We have observed and identified positive ions produced in a spark discharge in SF6 at high pressure. The ion species were found to be very sensitive to impurities. In purified SF6 the ions were sulfur-rich and complex before reacting to form chemically stable long-lived products. 相似文献
8.
Balawant S. Joshi Narayanan Viswanathan Dilip H. Gawad Venkatachalam Balakrishnan Wolfgang von Philipsborn 《Helvetica chimica acta》1975,58(8):2295-2305
Three new alkaloids designated as cyclostachine A (2), cyclostachine B (7) and cyclopiperstachine (10) have been isolated from Piper trichostachyon C. DC. Their structures have been derived on the basis of spectral and degradative studies and confirmed by synthesis. The 1H- and 13C-NMR. spectra of these compounds are discussed. 相似文献
9.
We discuss different compactifications of the spacial part 3 of Minkowski space and give classifications of the vacuum structure for a Yang-Mills theory.Partially supported by DFG and by Simon Fraser UniversityPartially supported by National Research Council of Canada grant 751-010 相似文献
10.
Viswanathan Karthickeyan Wang Shuang Esakkimuthu Sivakumar 《Journal of Thermal Analysis and Calorimetry》2021,146(5):2303-2315
Journal of Thermal Analysis and Calorimetry - The aim of present work is to improve the efficiency and reduce the harmful exhaust emissions from diesel engines. Neat lemongrass oil was selected as... 相似文献