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891.
892.
Flame–wall interaction (FWI) in premixed turbulent combustion has been analysed based on a counter-flow like configuration at the statistically stationary state. For the present configuration, the two FWI sub-zones, i.e the influence zone and the quenching zone, can be identified from the DNS results. Detailed analysis of the important quantities, such as the flame temperature, flame–wall distance, wall heat flux, flame curvature and dilatation (including the flame normal and tangential strain rates), and some orientation relations between the flame normal and the principal strain rate directions, have been reported, together with the physical explanations. All these statistical results are determined by the relative strengths of the wall heat flux, thermal expansion and the flame–turbulence interaction.  相似文献   
893.
894.
A high yielding, one-pot general procedure for the synthesis of ò-iodoalkyne is described.  相似文献   
895.
896.
The lithium, potassium, and ammonium salts of bis (2‐ethylhexyl) sulphosuccinic acid have been prepared from the sodium salt (AOT) by applying ion‐exchange technique. The critical micellization concentrations (cmc) of the surfactants with four different counterions have been determined at a temperature range of 10°C to 40°C using surface tension as well as electrical conductivity measurements. Observed data have been utilized to evaluate the ionization degree (counter ion association constant),α, and various thermodynamic parameters of micellization viz, free energy, enthalpy, entropy changes of micelle formation, and also the surface parameters (Γmax, Amin) in aqueous media. The value of cmc decreases with hydrated ionic size of the counter ions (except K+) and follows the order NH4 +>Na+>Li+>K+. While large negative free energy change (ΔG0 m) and the positive entropy change (ΔS0 m) favor the micellization process thermodynamically, nature of their variation with counterion supports the involvement of counterion size factor in micellization process via a change in the hydrophilicity of surfactant head group.  相似文献   
897.
898.
Benzoylation of primary amines and amino acids is efficiently carried out in a brine solution using a stoichiometric amount of benzoyl chloride followed by trituration with aqueous saturated bicarbonate solution.  相似文献   
899.
An inorganic ion exchanger, quinolinephosphomolybdate has been synthesized and characterized by elemental analysis, infrared (IR) and X-ray diffraction (XRD) spectroscopy. This compound is highly stable toward thermal, chemical and radiation dose. This has been employed in the separation of carrier-free 90Y from its parent 90Sr from an equilibrium mixture. The absorbed daughter was recovered by using 0.0284 mol L−1 ascorbic acid solutions at pH 5.0 as eluting agent.  相似文献   
900.
C-reactive protein (CRP) is a highly conserved plasma protein belonging to pentraxins, a superfamily which has significant proinflammatory role. Therefore, CRP can be a good target for drug discovery to prevent disease pathogenesis, especially cardioprotection in acute myocardial infarction and neuroprotection in stroke. Hence, the knowledge of the structure of CRP is very important. In this paper, we have demonstrated three-dimensional structure, conserved domains, and surface structure of human CRP with the help of bioinformatics analysis. We have also depicted that evolutionary relationship of CRP exists among the different species. Simultaneously, WebLogo has been generated to know the more conserved part of this medically important protein.  相似文献   
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