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151.
Radiation effects on the thermal boundary layer flow over a moving plate with convective boundary condition 总被引:2,自引:0,他引:2
The steady laminar boundary layer flow over a moving plate in a moving fluid with convective surface boundary condition and
in the presence of thermal radiation is investigated in this paper. Under certain conditions, the present problem reduces
to the classical Blasius and Sakiadis problems. The effects of radiation and convective parameters on the thermal field are
thoroughly examined and discussed. Dual solutions are found to exist when the plate and the fluid move in the opposite directions. 相似文献
152.
It has been suggested that pyridine and pyrrole could be patterns for imidazole reactivity studies due to the amine (-NH-) and aza (-N═) nitrogen atoms. The analyses of the local and global electronic indexes prove and quantify that imidazole has an intermediate analogy between pyrrole and pyridine. 相似文献
153.
Anthraquinones with antiplasmodial activity from the roots of Rennellia elliptica Korth. (Rubiaceae)
Osman CP Ismail NH Ahmad R Ahmat N Awang K Jaafar FM 《Molecules (Basel, Switzerland)》2010,15(10):7218-7226
Dichloromethane root extract of Rennellia elliptica Korth. showed strong inhibition of Plasmodium falciparum growth in vitro with an IC?? value of 4.04 μg/mL. A phytochemical study of the dichloromethane root extract has led to the isolation and characterization of a new anthraquinone, 1,2-dimethoxy-6-methyl-9,10-anthraquinone (1), and ten known anthraquinones: 1-hydroxy-2-methoxy-6-methyl-9,10-anthraquinone (2), nordamnacanthal (3), 2-formyl-3-hydroxy-9,10-anthraquinone (4), damnacanthal (5), lucidin-ω-methyl ether (6), 3-hydroxy-2-methyl-9,10-anthraquinone (7), rubiadin (8), 3-hydroxy-2-methoxy-6-methyl-9,10-anthraquinone (9), rubiadin-1-methyl ether (10) and 3-hydroxy-2-hydroxymethyl-9,10-anthraquinone (11). Structural elucidation of all compounds was accomplished by modern spectroscopic methods, notably 1D and 2D NMR, IR, UV and HREIMS. The new anthraquinone 1, 2-formyl-3-hydroxy-9,10-anthraquinone (4) and 3-hydroxy-2-methyl-9,10-anthraquinone (7) possess strong antiplasmodial activity, with IC?? values of 1.10, 0.63 and 0.34 μM, respectively. 相似文献
154.
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156.
S. A. Muhammed Ali Anwar Mustafa Raduwan Nor Fatina Muchtar Andanastuti Somalu Mahendra Rao 《Journal of Sol-Gel Science and Technology》2018,86(2):493-504
Journal of Sol-Gel Science and Technology - La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) is a perovskite-type oxide that exhibits excellent mixed ionic–electronic conducting properties and is a... 相似文献
157.
Mohd Nor M. K. Ho C. S. Maat N. Kamarulzaman M. F. 《Continuum Mechanics and Thermodynamics》2020,32(4):1217-1229
Continuum Mechanics and Thermodynamics - Excellent mechanical properties of composite materials have numerous engineering applications, especially in aerospace structures. The main characteristics... 相似文献
158.
Mohammad Khairul Azhar Abdul Razab Mohamad Suhaimi Jaafar Nor Hakimin Abdullah Mohamad Faiz Mohd Amin Mazlan Mohamed 《Journal of Russian Laser Research》2016,37(2):197-206
Laser coating removal is an approach that has the potential to replace conventional chemical-based stripping methods in industry. In addition to the laser parameters, the efficiency of this cleaning technique depends also on the coating system itself. For this reason, we study the influence of the elemental compositions of two Malaysian automotive coated substrates, referred to here as A and B, on laser coating removal mechanisms using the Cynosure Cynergy Nd:YAG laser. The optimum laser coating removal efficiencies for both samples A and B are determined based on the depths of 360 craters obtained using a given formula. Selected crater depths on both of the stipulated samples are then subjected to energy dispersive X-ray analysis to determine their elemental compositions. The results indicate that sample A, which has higher aluminum content, shows greater efficiency in coating system removal, with balanced carbon and oxygen compositions aiding coating reduction during the cleaning process. 相似文献
159.
160.
Engineering systems such as aircraft, ships and automotive are considered built-up structures. Dynamically they are taught of as being fabricated from many components that are classified as ‘deterministic subsystems’ (DS) and ‘non-deterministic subsystems’ (Non-DS). Structures' response of the DS is deterministic in nature and analysed using deterministic modelling methods such as finite element (FE) method. The response of Non-DS is statistical in nature and estimated using statistical modelling technique such as statistical energy analysis (SEA). SEA method uses power balance equation, in which any external input to the subsystem must be represented in terms of power. Often, input force is taken as point force and ensemble average power delivered by point force is already well-established. However, the external input can also be applied in the form of moments exerted by a piezoelectric (PZT) patch actuator. In order to be able to apply SEA method for input moments, a mathematical representation for moment generated by PZT patch in the form of average power is needed, which is attempted in this paper. A simply-supported plate with attached PZT patch is taken as a benchmark model. Analytical solution to estimate average power is derived using mobility approach. Ensemble average of power given by the PZT patch actuator to the benchmark model when subjected to structural uncertainties is also simulated using Lagrangian method and FEA software. The analytical estimation is compared with the Lagrangian model and FE method for validation. The effects of size and location of the PZT actuators on the power delivered to the plate are later investigated. 相似文献