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排序方式: 共有559条查询结果,搜索用时 265 毫秒
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Md. Abdur Rahim Shamim Mahbub Md. Kamrul Islam Sk. Md. Ali Ahsan Shahed Rana Malik Abdul Rub Anish Khan Md. Anamul Hoque 《Journal of surfactants and detergents》2020,23(2):457-470
Conductometric and cloud point (CP) measurement studies have been performed to investigate the interaction of tetradecyltrimethylammonium bromide (TTAB) and Triton® X-100 (TX-100) with ciprofloxacin hydrochloride (CFH) in different solvents over the temperature range of 295.15–315.15 K. CFH is used for the treatment of various bacterial infections. The observed critical micelle concentration (CMC) values of TTAB were found to be reduced in the presence of electrolytes (Na2SO4/Na3PO4), and this reduction proceeds with the elevation of salt concentration. The order of the CMC of TTAB follows the trend: > >. The observed CMC values of TTAB were found to increase with increasing temperature and decrease with increasing concentration of CFH in aqueous medium. The values of Gibbs free energy of micellization () for the TTAB/TTAB + CFH mixture were found to be negative, implying spontaneous micellization. The estimated CP of TX-100 decreases with increasing concentration of TX-100 in aqueous medium. The CP values first decrease with increasing concentration of CFH and then increase at higher concentration of CFH almost in all cases investigated. The values of free energy of clouding were found to be positive in all cases studied implying that phase separation of TX-100 was nonspontaneous. The other thermodynamic parameters associated with the micellization of TTAB and the phase separation of TX-100 were estimated and explained. 相似文献
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Silicon - In this paper, simulation of a monocrystalline silicon solar cell was done using PC1D software. The impact of different solar cell parameters, with their effects on power and efficiency,... 相似文献
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Hiroshi Ohta Tomoyuki Hirota Abdur Rahim 《The International Journal of Advanced Manufacturing Technology》2007,33(1-2):36-41
This paper analyzes a multi-product production / inventory system where demands for each item arrive according to a Poisson
process and the production time for each product has an Erlang distribution. The paper proposes an optimality condition that
specifies whether each product should be produced make-to-stock or make-to-order. In the event a product should be produced
make-to-stock, an approach for computing the optimal base-stock level is proposed. Numerical examples are given for illustrative
purpose. 相似文献
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On the Hybrid Optimal Control Problem: Theory and Algorithms 总被引:1,自引:0,他引:1
A class of hybrid optimal control problems (HOCP) for systems with controlled and autonomous location transitions is formulated and a set of necessary conditions for hybrid system trajectory optimality is presented which together constitute generalizations of the standard Maximum Principle; these are given for the cases of open bounded control value sets and compact control value sets. The derivations in the paper employ: (i) classical variational and needle variation techniques; and (ii) a local controllability condition which is used to establish the adjoint and Hamiltonian jump conditions in the autonomous switching case. Employing the hybrid minimum principle (HMP) necessary conditions, a class of general HMP based algorithms for hybrid systems optimization are presented and analyzed for the autonomous switchings case and the controlled switchings case. Using results from the theory of penalty function methods and Ekeland's variational principle the convergence of these algorithms is established under reasonable assumptions. The efficacy of the proposed algorithms is illustrated via computational examples. 相似文献
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Abdulla A. Shaikh S. M. Javaid Zaidi 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1993,56(2):139-145
The absorption and reaction of oxygen in aqueous alkaline solutions of sodium dithionite has been experimentally investigated in a novel gas-liquid contactor. The novel gas-lift bubble column contactor was used to study the kinetics over wide ranges of reactant concentrations, temperature, and pH. The oxygen-sodium dithionite reaction was found to be first-order with respect to dithionite in the range of dithionite concentration < 0.1 M, and second-order in the range of dithionite concentration > 0.1 M. The reaction with respect to oxygen was found to be zero-order for all dithionite concentrations. These results and experimental investigations of the effect of solution alkalinity and temperature on the reaction rate are consistent with previous findings obtained in different gas-liquid contactors. The results thus confirm the feasibility of using the gas-lift bubble column for the kinetics of gas-liquid reactions. 相似文献