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181.
K. Mathew C. M. Nagarani A. S. Kirankumar 《International journal of remote sensing》2013,34(16):3237-3251
A physical model of split-window and multi-angle algorithms for the retrieval of sea surface temperature has been obtained. It is shown that optical thickness in the thermal infrared window region is approximately represented by a separable function of wavelength and atmospheric variables which greatly simplify the radiative transfer model. In modelling the temperature retrieval algorithms we exploit the correlation that exists between the sea surface temperature and the average temperature of the atmosphere. It is shown that, to the extent this correlation is maintained, there is a simple relationship between surface temperature and the brightness temperatures measured in two split-window or multi-angle channels. The different atmospheric conditions which cause spread in this relationship are briefly discussed. It is shown that measurements at three optical thicknesses instead of two as in the case of the split-window method improve the SST retrieval accuracy since it can take care of non-equilibrium conditions such as inversions, surface instabilities, etc., prevailing in the atmosphere. 相似文献
182.
In this work, the outcomes of interactions of counter-rotating vortex pairs with developing ignition kernels are studied. The conditions are selected to represent those in a lean-burn natural-gas engine with hot-jet ignition. The evolution of flame surface area during kernel–vortex interaction is quantitatively and qualitatively examined. It is observed that flame development is accelerated and the net flame surface area growth rate, i.e. heat release rate, increased with increasing vortex velocity. In general, increasing the vortex length scale increases the surface growth rate, i.e. increases heat release rates, but for small length scales, i.e. when the ratio of vortex length scale to kernel diameter is small, high flame curvature induced during the interaction leads to flame weakening and slower growth rates. When the vortex velocity is high relative to the flame speed and the length scale is comparable to the kernel diameter, the vortex breaks through the ignition kernel carrying with it hot products of combustion. This accelerates growth of the flame surface area and heat release rates compared to a kernel with no vortex interaction. On decreasing the vortex velocity and increasing the length scale, the wrinkling of the kernel becomes important. This also results in increased surface growth rates and higher heat release rates. 相似文献
183.
Research efforts have long been directed at understanding variations in collaborative behaviors among work teams with burgeoning interest in teams operating in knowledge-intensive settings. One of the largely unexplained issues is how does team image and collective identification facilitate collaborative behaviors. Here, survey data were collected from nineteen highly technical work teams engaging in software development in an R&D division of a multinational NASDAQ firm involved in multimedia communications and information processing technology. The relationships between perceived external prestige, collective team identification and team collaborative behaviors were examined. The results of the team-level analyses suggest that perceived external prestige augments collective team identification (measured at Time 1), which in turn engenders a high degree of collaboration and interaction within the team (measured at Time 2). When past team performance was controlled for, the results consistently supported the hypothesized model. 相似文献
184.
Cormac O. Laoire Edward Plichta Mary Hendrickson Sanjeev Mukerjee K.M. Abraham 《Electrochimica acta》2009,54(26):6560-6564
We carried out a detailed study of the kinetics of oxidation of ferrocene (Fc) to ferrocenium ion (Fc+) in the non-aqueous lithium ion conducting electrolyte composed of a solution of 1 M LiPF6 in 1:1 EC:EMC solvent mixture. This study using cyclic (CV) and rotating disk electrode (RDE) voltammetry showed that the Fc0/Fc+ redox couple is reversible in this highly concentrated electrolyte. The ferrocene and ferrocenium ion diffusion coefficients (D) were calculated from these results. In addition, the electron transfer rate constant (k0) and the exchange current density for the oxidation of ferrocene were determined. A comparison of the kinetic data obtained from the two electrochemical techniques appears to show that the data from the RDE experiments are more reliable because they are collected under strict mass transport control. A Tafel slope of c.a. 79 mV/decade and a transfer coefficient α of 0.3 obtained from analysis of the RDE data for ferrocene oxidation suggest that the structure of the activated complex is closer to that of the oxidized specie due to strong interactions with the carbonate solvents. The experiments reported here are relevant to the study of redox reagents for the chemical overcharge protection of Li-ion batteries. 相似文献
185.
186.
A comparison made between spouted-bed and two-impinging-streams reactors proved the superiority of the-impinging-streams dryer The latter device exhibited, on the one hand, relatively small energy requirements for pumping the phases through the reactor and, on the other hand, improved drying characteristics Thus the two-imping-streams reactor is recommended as a useful device for drying operations 相似文献
187.
188.
Conducted 4 studies with 218 undergraduates in an attempt to integrate hypotheses about the effects of thought and schema complexity on attitude polarization proposed by P. W. Linville (see record 1982-25791-001) and the 2nd author and C. Leone (see record 1978-09847-001). Linville's work showed that more extreme attitudes were associated with simpler cognitive schemas for construing the attitude object. The 2nd author and Leone demonstrated that thought with a complex schema resulted in greater attitude polarization than thought with a simple schema. Study 1 validated the present author's schema complexity manipulation. Study 2 tested and found support for the hypothesis that 1 moderating variable was motivational: The 2nd author and Leone's effect was obtained in the presence of commitment to an initial evaluation, and there was a tendency toward the Linville effect in the absence of commitment to an initial evaluation. Study 3 tested and found support for the hypothesis that another moderating variable was structural: The Linville effect was obtained when there was little correlation among the dimensions of the cognitive schema, and the 2nd author and Leone's effect was obtained when there was substantial correlation among the dimensions; thought tended to increase the correlation among dimensions. Study 4 tested and found support for the hypothesis that commitment affects cognitive structures in a way that could account for its moderating effect on attitude polarization. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
189.
The effects of three reaction temperatues, 180, 200 and 220°C, on the partial wet oxidation of peat were investigated. A stirred reactor with a five litre working volume and continuous feed of peat slurry and air was used for the experiments. The effluent was separated into liquid and solid fractions and analyzed to quantify the effects of temperature. The carbon content and heating value of the recovered solids increased with temperature but yields were lower. The composition of the wastewater was only slightly dependent on the reaction temperature, and in all cases contained high concentrations of organics. 相似文献
190.