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151.
Sajid Husain P. Nageswara Sarma G. Y. S. K. Swamy K. Sita Devi 《Journal of the American Oil Chemists' Society》1993,70(2):149-155
Physicochemical data such as vapor pressures (p0), heats of vaporization (ΔHv), activity coefficents at infinite dilution (γ∞) and excess partial molar entropy (ΔS
e
0
) are considered important for conducting unit processes and designing reactor equipment. Scanty information regarding such
data is available in the literature for the higher fatty acid methyl esters. The objective of this research was to determine
the physicochemical properties of higher fatty acid methyl esters (C11–C23) by a gas-liquid chromatographic technique with SE-30 and diethylene glycol adipate as stationary phases. Correlations between
carbon numbers and various thermodynamic properties have indicated definite trends, which could be useful in predicting the
properties of unknown fatty acid methyl esters. The data generated may be useful to chemical engineers in the construction
of storage tanks, solvent extractors and distillation columns.
IICT communication no. 2993. 相似文献
152.
S. Rafat Husain J. Cillard P. Cillard 《Journal of the American Oil Chemists' Society》1987,64(1):109-111
α-Tocopherol at high concentration (1.25×10−4M) exhibited a prooxidant effect during autoxidation of linolenic and arachidonic acids. This prooxidant activity involved
a significant increase of the conjugated diene level, especially with linolenic acid. High performance liquid chromatographic
evaluation of malondialdehyde, a by-product of the hydroperoxides of polyunsaturated fatty acids, showed that malondialdehyde
was not increased during prooxidant effect ofα-tocopherol. Thus, malondialdehyde does not seem to be a good indicator for the manifestation of the prooxidant activity ofα-tocopherol. 相似文献
153.
Recent studies have provided new insights into the visuomotor functions of the dorsal and ventral regions of the lateral pre-motor cortex. Anatomical and physiological investigations in non-human primates have demonstrated that these regions have differing patterns of cortical connectivity and distinctive neuronal responses. Brain-imaging techniques and lesion studies have begun to probe the functions of homologous regions in humans. 相似文献
154.
In a previous experiment, field emission was observed from sharply pointed CdS single crystals. The experiments have now been extended, illuminating the tip with light from a pulsed argon-ion laser. It was found that (a) the voltage threshold at which emission can be observed is reduced, typically from 500 to 400 V, (b) under some conditions, the emission is increased by a factor of 103, (c) this emission persists for more than 2×10?2s after the laser pulse and appears to have two characteristic decay times, (d) the emission is approximately proportional to the light intensity and (e) the greatest photo-enhanced field emission was obtained with the laser light shining axially on the emitting area of the tip. 相似文献
155.
ABSTRACT In this article, system dynamics of a complete photovoltaic system have been studied. A small signal transient analysis model has been established to examine the effects of small change in the duty cycle of the converter as well as the time steps between each perturbation on the system dynamics. All efforts have been made to do a detailed analysis using almost all the equations involved. Sample calculations (using the simulated system model) are also shown so as to approximately analyse the perturbation effects. It is shown that the value of the step size of the duty cycle should be taken large for points far away from the maximum power point (MPP) and small for points near the MPP. Also, the time between two consecutive perturbations should be at least equal to the settling time. This article is very useful for the researchers to choose a proper delay between two consecutive perturbations and selection of the optimum value of the step size. 相似文献
156.
Husain Murtuja Meena Lalit Ghosh M. Prabhu N. 《Metallurgical and Materials Transactions A》2021,52(6):2642-2656
Metallurgical and Materials Transactions A - In the present investigation, friction stir welding (FSW) was carried out on C-Mn steel using various welding parameters. The microstructural... 相似文献
157.
Nasser A. Al-Shabib Javed Masood Khan Ajamaluddin Malik Md. Tabish Rehman Fohad Mabood Husain Mohamed F. AlAjmi Osama Hamdan Ali Alghamdi Altaf Khan 《Journal of dairy science》2021,104(5):5141-5151
Amyloid fibril formation of proteins is associated with a number of neurodegenerative diseases. Several small molecules can accelerate the amyloid fibril formation in vitro and in vivo. However, the molecular mechanism of amyloid fibrillation is still unclear. In this study, we investigated how the food dye quinoline yellow (QY) induces amyloid fibrillation in α-lactalbumin (α-LA), a major whey protein, at pH 2.0. We used several spectroscopy techniques and a microscopy technique to explore how QY provokes amyloid fibrillation in α-LA. From turbidity and Rayleigh light scattering experiments, we found that QY promotes α-LA aggregation in a concentration-dependent manner; the optimal concentration for α-LA aggregation was 0.15 to 10.00 mM. Below 0.1 mM, no aggregation occurred. Quinoline yellow–induced aggregation was a rapid process that escaped the lag phase, but it depended on the concentrations of both α-LA and QY. We also demonstrated that aggregation switched the secondary structure of α-LA from α-helices to cross-β-sheets. We then confirmed the amyloid-like structure of aggregated α-LA by transmission electron microscopy measurements. Molecular docking and simulation confirmed the stability of the α-LA-QY complex due to the formation of 1 hydrogen bond with Lys99 and 2 electrostatic interactions with Arg70 and Lys99, along with hydrophobic interactions with Leu59 and Tyr103. This study will aid in our understanding of how small molecules induce aggregation of proteins inside the stomach (low pH) and affect the digestive process. 相似文献
158.
In this study, we have investigated the structure, temperature-dependent resistivity, magnetization, and dielectric properties of La1?x Te x MnO3±δ (x = 0.10 and 0.15). X-ray diffraction analysis confirms the rhombohedral crystal symmetry with space group R $ \overline{3} $ c. For both the samples, the temperature dependence of magnetization plots show paramagnetic-to-ferromagnetic phase transition. The Curie temperature (T c) and magnitude of magnetization increase with the Te concentration. Field-dependent magnetization produces the asymmetric hysteresis loop that has been attributed to the magneto crystalline anisotropy induced by lattice distortion and the rare earth spin coupling at room temperature. Temperature-dependent resistivity plots exhibit metal–insulator transition (MIT) and charge-ordering state. These plots have been fitted using variable range hopping model, and the density of states [N(EF)] has been estimated. Magnetoresistance is measured as a function of temperature in the field of 1T, 5T, and 8T. The dielectric constant shows an anomaly near MIT. The dielectric constant exhibits a peaking behavior with the applied frequency and the temperature dependence of dielectric constant attains colossal values at high temperatures. 相似文献
159.
Marwah Al-Azzawi Afzal Husain Farouk S. Mjalli Talal Al-Wahaibi Abdulaziz Al-Hashmi Basim Abu-Jdayil 《化学工程与技术》2020,43(10):1951-1958
Microscale processes offer a substantial advantage to the process industry as separation is conducted rapidly and efficiently. However, the effectiveness of the separation depends on the stability of the flow regime. Experimental and numerical analysis was carried out to characterize the flow patterns of polyethylene glycol 200 (PEG200) and diesel fuel at several flow ratios in order to achieve optimal conditions for a stable pattern. Computational fluid dynamics (CFD) was employed using the volume-of-fluid (VOF) model and the results were validated with the experimental data. Both experimental and numerical outcomes revealed two-phase flow patterns. These findings enable the application of the simulated module for further liquid-liquid mass transfer studies where sulfuric compounds exist as solutes in the fuel. 相似文献
160.
Singular subarcs appear in the solution of an optimal control problem when one or more of the control variables appear linearly in both the performance index and differential constraint equations or just in the constraint equations. In such cases, the Pontryagin's(1) Maximum Principle yields no information regarding the possible candidates for such subarcs to be optimal trajectories, since the associated Hamiltonian is also linear in the control variables. In the chemical engineering literature such problems have been reported, for instance, in the optimal control of a continuous stirred reactor(2,3,4) in the optimally distributed feed reactors(5), in the optimal catalyst distribution along a tubular reactor(6,7) and in the optimal design of a plug flow tubular reactor(8). 相似文献