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91.
A mathematical model was developed for the iron ore sintering process considering all the major thermochemical phenomena in the system, assuming both the static and moving bed configurations. The model predicted a large number of parameters pertinent to the sintering process including the temperatures of the gas and solid, concentration of various species, amount of solid melted etc. The results were tested against the data existing in literature, and a limited number of pot tests conducted in a pilot plant. Despite high complexity of the problem, the agreement between the experimental and simulated data was reasonably good. 相似文献
92.
Although the beta-adrenergic receptor kinase (betaARK) mediates agonist-dependent phosphorylation and desensitization of G protein-coupled receptors, recent studies suggest additional cellular functions. During our attempts to identify novel betaARK interacting proteins, we found that the cytoskeletal protein tubulin could specifically bind to a betaARK-coupled affinity column. In vitro analysis demonstrated that betaARK and G protein-coupled receptor kinase-5 (GRK5) were able to stoichiometrically phosphorylate purified tubulin dimers with a preference for beta-tubulin and, under certain conditions, the betaIII-isotype. Examination of the GRK/tubulin binding characteristics revealed that tubulin dimers and assembled microtubules bind GRKs, whereas the catalytic domain of betaARK contains the primary tubulin binding determinants. In vivo interaction of GRK and tubulin was suggested by the following: (i) co-purification of betaARK with tubulin from brain tissue; (ii) co-immunoprecipitation of betaARK and tubulin from COS-1 cells; and (iii) co-localization of betaARK and GRK5 with microtubule structures in COS-1 cells. In addition, GRK-phosphorylated tubulin was found preferentially associated with the microtubule fraction during in vitro assembly assays suggesting potential functional significance. These results suggest a novel link between the cytoskeleton and GRKs that may be important for regulating GRK and/or tubulin function. 相似文献
93.
Keka Ojha Narayan C Pradhan Amar Nath Samanta 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2006,81(4):659-666
The alkylation of phenol with tert‐butyl alcohol was carried out in a continuous flow reactor over a catalyst synthesized from fly ash. The activity of the synthesized catalyst was compared with those of other conventional zeolite catalysts such as 13X (NaX) and Hβ. Of all the catalysts tested, zeolite Hβ showed the highest activity in phenol conversion followed by the synthesized zeolite (HZOP‐31). The activity of commercial 13X zeolite was found to be same as that of HZOP‐31. Ce‐exchanged catalyst (CeZOP‐31) showed even better performance than 13X in the alkylation of phenol. The effects of different parameters such as reactant mole ratio, temperature and space velocity on phenol conversion and tert‐butyl phenol selectivity were studied. The effect of mass transfer resistance was found to be negligible within the feed rate range and particle size range studied. The apparent activation energy for the reaction of tert‐butyl alcohol over HZOP‐31 was determined as 30.1 kJ mol?1. Copyright © 2006 Society of Chemical Industry 相似文献
94.
Smita Chaubey Purushottam Joshi Manoj Kumar Rajesh Arya A. K. Nath Sanjay Kher 《Sadhana》2007,32(5):513-519
Long Period Gratings (LPGs) have been developed using carbon dioxide laser in a standard optical fibre. LPGs with a periodicity
of 600 μm and grating length of 24 mm have been inscribed on standard single mode fibre. Such gratings have been used in designing
temperature sensors and temperature is monitored up to 80°C. The sensitivity of such type of sensor is 0·06 nm/°C where as
for standard Fibre Bragg Grating (FBG) it is 0·011 nm/°C. The LPG performance is also evaluated after γ-ray irradiation for total dose of 5 KGy and has not shown any effect on transmission spectrum. 相似文献
95.
Ravinder Nath 《Behaviour & Information Technology》1992,11(1):24-31
More and more organizations are seeking innovative ways to use information technology (IT) for strategic advantage. One way to gain this competitive edge is by differentiating the services provided to customers. This paper provides a framework to identify areas ripe for the implementation of IT to enhance and improve customer service. The framework is based upon the examination of the existing service delivery system of an organization and how applications of IT might change the interfaces among the various players (customers, employees, etc.) in the service delivery system. Further, examples are presented to illustrate how some organizations have achieved superior service quality by creatively utilizing simple IT tools. 相似文献
96.
97.
The non-similar boundary layer flow of a viscous incompressible electrically conducting fluid over a moving surface in a rotating fluid, in the presence of a magnetic field, Hall currents and the free stream velocity has been studied. The parabolic partial differential equations governing the flow are solved numerically using an implicit finite-difference scheme. The Coriolis force induces overshoot in the velocity profile of the primary flow and the magnetic field reduces/removes the velocity overshoot. The local skin friction coefficient for the primary flow increases with the magnetic field, but the skin friction coefficient for the secondary flow reduces it. Also the local skin friction coefficients for the primary and secondary flows are reduced due to the Hall currents. The effects of the magnetic field, Hall currents and the wall velocity, on the skin friction coefficients for the primary and secondary flows increase with the Coriolis force. The wall velocity strongly affects the flow field. When the wall velocity is equal to the free stream velocity, the skin friction coefficients for the primary and secondary flows vanish, but this does not imply separation. 相似文献
98.
99.
S. Reaz Ahmed S. K. Deb Nath M. Wahhaj Uddin 《International journal for numerical methods in engineering》2005,64(6):729-750
Optimum design of tire‐tread sections is an important practical issue. However, useful study of the problem that can suggest a reliable guideline for determining the optimum tread sections had hardly been made in the past. The present paper describes a new analysis of the state of stresses in tire‐tread sections in contact with the road surface, taking special care of the boundary conditions. Based on the analysis, a method is proposed to determine the optimum tread shapes for avoiding lateral slippage between tires and roads. The displacement potential function formulation, an ideal mathematical model for the practical stress problems, has been used in conjunction with finite‐difference method of solution. For the present analysis, lateral slipping in absence of frictional resistance as well as the no‐slip conditions of the tire‐tread contact surface have been considered along with a large number of tread aspect ratios. The present computational approach proves to be a powerful tool for determining the optimum tread shapes for avoiding the lateral slippage of tire‐treads. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
100.