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231.
Acrylamide was polymerized in aqueous solution at 35 ± 0.2°C with the redox pair potassium permanganate/lactic acid. The kinetics of polymerization was followed iodometrically. The effect of monomer, potassium permanganate, and lactic acid concentration and temperature on the rate of polymerization was studied. The dependence of the number-average degree of polymerization on the initial rate of polymerization and temperature was also determined. 相似文献
232.
K. B. Misra 《International Journal of Mathematical Education in Science & Technology》2013,44(3):207-215
Dynamic programming formulation for obtaining the optimum number of redundancies at each stage in a system is explained in detail. It is also emphasized and illustrated by examples, that the ‘summation’ form of functional equations, as suggested in the paper, provide a faster solution to an otherwise computationally voluminous method. 相似文献
233.
The present investigation was carried out to screen compatibility of some diluents with pefloxacin mesilate using differential
scanning calorimetry (DSC), isothermal stability studies, along with stability studies in liquid state and to assign relative
ranking to diluents. Compatibility was predicted with MCC101, MCC102, DCP anhydrous, Emcompress, while melting endotherm of
drug was lost in admixtures of dextrose anhydrous, Pearlitol, Lactopress spray dried, Lactochem fine powder and Lycatab indicating
possibility of interaction. Enthalpy changes were used for relative ranking of diluents. 相似文献
234.
Kaushal Kumar Mahato Shivesh Sabbarwal Nira Misra 《International Journal of Polymer Analysis and Characterization》2020,25(5):353-361
Abstract Hydrogel composites from polyvinyl alcohol and chitosan have been developed by various researchers as a function of their composition for various medical applications. Although, the solubility of chitosan in acidic solvents may limit its wide bioengineering applications. In this article, we demonstrate that polyvinyl alcohol-chitosan oligosaccharide (water soluble) to develop cross-linked hydrogel network using chemical cross linker. X ray diffraction, Fourier transform infrared spectroscopy, and wettability study of these hydrogels were also performed. Lomefloxacin drug was loaded into the hydrogels and its release profile was studied. 相似文献
235.
236.
Dr. Esther Frederick Dr. Quinn Campbell Dr. Igor V. Kolesnichenko Dr. Luis F. Peña Dr. Angelica Benavidez Dr. Evan M. Anderson Dr. David R. Wheeler Dr. Shashank Misra 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(53):13337-13341
Ultradoping introduces unprecedented dopant levels into Si, which transforms its electronic behavior and enables its use as a next-generation electronic material. Commercialization of ultradoping is currently limited by gas-phase ultra-high vacuum requirements. Solvothermal chemistry is amenable to scale-up. However, an integral part of ultradoping is a direct chemical bond between dopants and Si, and solvothermal dopant-Si surface reactions are not well-developed. This work provides the first quantified demonstration of achieving ultradoping concentrations of boron (∼1e14 cm2) by using a solvothermal process. Surface characterizations indicate the catalyst cross-reacted, which led to multiple surface products and caused ambiguity in experimental confirmation of direct surface attachment. Density functional theory computations elucidate that the reaction results in direct B−Si surface bonds. This proof-of-principle work lays groundwork for emerging solvothermal ultradoping processes. 相似文献
237.
Three phytochemicals, curcumin 1, demethoxycurcumin 2 and β-sitosterol-3-O-β-d-glucopyranoside 3 have been isolated from the ethyl acetate extract of rhizomes of Curcuma aromatica. Chemical structures of all the three isolates were determined using spectroscopic and chemical analyses. β-Sitosterol-3-O-β-d-glucopyranoside has been isolated for the first time from this plant. 相似文献
238.
K. P. Harikrishnan G. Ambika R. Misra 《The European physical journal. Special topics》2013,222(3-4):839-846
Transition to hyperchaos is uaually studied by computing the spectrum of Lyapunov Exponents (LE). But such a procedure can be employed mainly when the equations governing the dynamical system are known. However, if the information available on the system is only through time series, the method becomes difficult to implement. We show that the transition to hyperchaos is followed by a sudden change in the topological structure of the underlying attractor. Our numerical results indicate that the transition to hyperchaos can be characterized accurately through the computation of correlation dimension (D 2) from time series. We use two standard time delayed hyperchaotic systems as examples since, for such systems, D 2 varies smoothly as a function of the time delay τ which can be used as the control parameter. 相似文献
239.
240.
S. K. Misra Rolf O. Skld 《Colloids and surfaces. A, Physicochemical and engineering aspects》2000,170(2-3):91-106
Phase and aggregational behavior of model metal working formulations of the inversely soluble type was studied with the aid of a new analytical tool. Correlations between these data and measured anti-wear performance data are discussed. The aim was to gain some insight into the mode of variation of the anti-wear effect with temperature and concentration depending on composition of inversely soluble formulations, despite the complexity of the systems. A comparison with a conventional synthetic metal working fluid indicated inherent advantages of inversely soluble concepts at elevated temperatures. Thus, as temperature is increased, as occurs in a friction contact, wear is more effectively mitigated with a suitable formulated inversely soluble system. Typically, as shown experimentally in this paper, the behavior is different from data observed with a conventional metal working fluid formulation. A substantial dependence of the anti-wear effect on the adsorption of boundary lubricating components is inferred from a study of correlation between monomer concentration and extent of wear. These experiments were conducted on surfactant concentrations exceeding critical micelle concentration (CMC) to various degrees. Findings also indicate a particular potential to optimize lubrication performance by exploiting synergetic effects observed in a combination of two different types of alkoxylated compounds. The investigated types of formulations offer particularly good prospects for effective contaminant removal without loss of active matter. This is favorable from an occupational health and environmental standpoint, due to the possibility to exchange biocides with mechanical means of microbial control and an improved potential for a long service life. 相似文献