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991.
992.
Sarah Spence Adams Matthew Crawford Caitlin Greeley Bryce Lee Mathav Kishore Murugan 《Designs, Codes and Cryptography》2009,51(3):245-252
Multilevel Hadamard matrices (MHMs), whose entries are integers as opposed to the traditional restriction to {±1}, were introduced
by Trinh, Fan, and Gabidulin in 2006 as a way to construct multilevel zero-correlation zone sequences, which have been studied
for use in approximately synchronized code division multiple access systems. We answer the open question concerning the maximum
number of distinct elements permissible in an order n MHM by proving the existence of an order n MHM with n elements of distinct absolute value for all n. We also define multidimensional MHMs and prove an analogous existence result.
相似文献
993.
Partha Ghosal Sama Ajay Sanjeev Meena Sudhir Sinha Arun K. Shaw 《Tetrahedron: Asymmetry》2013,24(24):1625
994.
B. K. Sarkar B. Sinha M. N. Roy 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2008,82(6):960-966
The apparent molar volumes (V
ϕ) and viscosity B-coefficients of sodium molybdate and sodium tungstate in aqueous binary mixtures of acetonitrile were determined from solution
density and viscosity measurements at 298.15, 308.15 and 318.15 K and various electrolyte concentrations. The experimental
density and viscosity data were evaluated by the Masson and Jones-Dole equations, respectively, and the parameters derived
were interpreted in terms of ion-solvent and ion-ion interactions. The activation parameters of viscous flow were also determined
and discussed using transition state theory.
The article is published in the original. 相似文献
995.
Resonant soft X-ray reflectivity measurements at and near the L3 absorption edge of sulphur have been performed on mechanically polished zinc sulphide using Indus-1 synchrotron source. A sulphur rich surface (∼15 nm thick) consisting of two layers with gradient electron density distribution was uniquely determined. As compared to bulk ZnS, the top layer has ∼30-50% less electron density whereas, the intermediate layer has ∼10-18% less electron density. Conventional hard X-ray reflectivity measurement at Cu Kα wavelength also indicates low electron density (sulphur rich) surface of ZnS but the technique was found insensitive for unique determination of electron density distribution. Optical constants of ZnS in the soft X-ray region (100-250 eV) have been reported for the first time and were in good agreement with the theoretically reported values. 相似文献
996.
Binary mixtures of irregular materials of different particle sizes and/or particle densities are fluidized in a 15-cm diameter column with a perforated plate distributor. An attempt has been made in this work to determine the segregation characteristics of jetsam particles for both the homogeneous and heterogeneous binary mixtures in terms of segregation distance by correlating it to the various system parameters, viz. initial static bed height, height of a layer of particles above the bottom grid, superficial gas velocity and average particle size and/or particle densities of the mixture through the dimensional analysis. Correlation on the basis of Artificial Neural Network approach has also been developed with the above system parameters thereby authenticating the development of correlation by the former approach. The calculated values of the segregation distance obtained for both the homogeneous and heterogeneous binary mixtures from both the types of fluidized beds (i. e. under the static bed condition and the fluidized bed condition) have also been compared with each other. 相似文献
997.
T. Kishore kumar M. Victor Antony Raj P. Sagayaraj 《Journal of Physics and Chemistry of Solids》2008,69(11):2634-2638
Physical properties such as photoconductivity, dielectric and thermal stability have been investigated for pure benzoyl glycine (BG) crystals. In addition to this, the influence of dopants (benzophenone and iodine) of these properties on BG crystals has been studied. Photoconductivity studies on pure BG, benzophenone-and iodine-doped BG revealed the positive photoconducting nature. The dielectric responses of the samples have been studied in the frequency range 100 Hz-500 KHz at room temperature and the results are discussed in detail. The thermogravimetric studies of pure and doped BG crystals indicate that the presence of dopants has slightly increased the decomposition temperature of pure BG samples, thereby enhancing thermal stability to the doped ones. 相似文献
998.
K. Kishore 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(6):937-942
Studies on the low temperature oxidation of polyolefins have been the subject matter of several investigations because of interest in understanding the aging and weathering of polymers. One of the key steps in such an oxtdatton is the formation of hydroperoxide. Estimation of the hydroperoxide in oxidized samples, which is conventionally done by iodometric titrations, is quite important to gain knowledge about the kinetics and mechanism of the process. The present investigation is the first report of the thermal analysis of polypropylene hydroperoxide samples from two angles: (1) the thermal behavior of its decomposition and (2) whether such an analysis leads to knowledge of the concentration of hydroperoxide in the sample. 相似文献
999.
Pankaj Kisan Chatki Kishore Kumar Hotha Pandu Ranga Reddy Kolagatla D. Vijaya Bharathi V. Venkateswarulu 《Biomedical chromatography : BMC》2013,27(7):838-845
A robust, specific and fully validated LC‐MS/MS method as per general practices of industry has been developed for estimation of lacidipine (LAC) with 100 μL of human plasma using lacidipine‐13C8 as an internal standard (IS). The API‐4000 LC‐MS/MS was operated under the multiple reaction‐monitoring mode. A simple liquid–liquid extraction process was used to extract LAC and IS from human plasma. The total run time was 3.0 min and the elution of LAC and IS occurred at 1.96 and 1.97 min; this was achieved with a mobile phase consisting of 5 mm ammonium acetate buffer–acetontrile (15:85 v/v) at a flow rate of 0.60 mL/min on a Zorbax SB C18 (50 × 4.6 mm, 5 µm) column. A linear response function was established for the range of concentrations 50–15,000 pg/mL (r > 0.998) for LAC. The current developed method has negligible matrix effect and is free from unwanted adducts and clusters which are formed owing to system such as solvent or mobile phase. The developed assay method was applied to an oral pharmacokinetic study in humans and successfully characterized the pharmacokinetic data up to 72 h. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
1000.
The Kolmogorov-Johnson-Mehl-Avrami model for isothermal transformation kinetics is universal under specific assumptions. However, the experimental Avrami exponent deviates from the universal value. In this context, we study the effect of transient heterogeneous nucleation on the Avrami exponent for bulk materials and also for transformations leading to nanostructured materials. All transformations are assumed to be polymorphic. A discrete version of the KJMA model is modified for this purpose. Scaling relations for transformations under different conditions are reported. 相似文献