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251.
This work presents a similarity solution for boundary layer flow through a porous medium over a stretching porous wall. Two
considered wall boundary conditions are power-law distribution of either wall temperature or heat flux which are general enough
to cover the isothermal and isoflux cases. In addition to momentum, both first and second laws of thermodynamics analyses
of the problem are investigated. Independent numerical simulations are also performed for verification of the proposed analytical
solution. The results, from the two independent approaches, are found to be in complete agreement. A comprehensive parametric
study is presented and it is shown that heat transfer and entropy generation rates increase with Reynolds number, Prandtl
number, and suction to the surface. 相似文献
252.
Nonlinear Dynamics - The development of a two-loops Quadrotor’s robust generalized dynamic inversion (RGDI)-based control system is presented. The outer (position) loop utilizes PD position... 相似文献
253.
Raju Suresh Kumar Abdulrahman I. Almansour Natarajan Arumugam Govindasami Periyasami S. Athimoolam Raju Ranjith Kumar Mohammad Asad Abdullah M. Asiri 《Tetrahedron letters》2018,59(35):3336-3340
The stereoselective syntheses of novel dispiro acenaphthylene–indolizine–pyridinone hybrid heterocycles have been achieved through one-pot four-component domino 1,3-dipolar cycloaddition–Michael addition–air oxidation sequence of reactions. 相似文献
254.
Zahra Pirmohammadi Abdulrahman Bahrami Davood Nematollahi Saber Alizadeh Farshid Ghorbani Shahna Razzagh Rahimpoor 《Biomedical chromatography : BMC》2020,34(1):e4725
For the analysis of methylhippuric acids (MHAs) in human urine samples, in this study, a new method based on the metal–organic framework (MOF) of MIL-53-NH2 (Al) in microextraction by packed sorbent (MEPS) was developed. The synthesis of MIL-53-NH2 (Al) was characterized by Fourier transform infrared spectra, field emission-scanning electron microscopy and X-ray diffraction. Response surface methodology was used to investigate the influences of several parameters including type and volume of elution, type of conditional solvent, sample volume and extraction cycle on MEPS efficiency. The results showed good recoveries (>94%) and excellent extraction efficiencies (>96%) at three different concentrations of 50, 500 and 1500 μg ml−1 (as low, mid and high concentrations, respectively) of MHA isomers. Calibration curves of MHAs were linear over the concentration range of 1–1500 μg ml−1, with high correlation coefficients (r ≥ 0.998). The reproducibility of the proposed MIL-53-MEPS for determination of three isomers of MHA was found to be in the range of 3.5–11.1%. After optimization of the proposed technique, it was used to analyze MHAs in urine samples of workers exposed to xylenes in a petrochemical plant in Asalouyah, Iran. The results indicated that the MOF–MEPS method was selective, sensitive, rapid and efficient for the extraction of urinary MHAs. The technique is also environmentally friendly and inexpensive, and the MOF sorbent is reusable. 相似文献
255.
Journal of Applied Mechanics and Technical Physics - A new design for continuous separation of multiple blood cells from diluted whole blood in a microfluidic device based on dielectrophoresis... 相似文献
256.
Dabiri Erfan Bahrami Farhad Mohammadzadeh Soroush 《Journal of Thermal Analysis and Calorimetry》2018,131(3):2243-2259
Journal of Thermal Analysis and Calorimetry - The main purpose of this research is to investigate the effect of using SiC/water and MgO/water nanofluids on convection heat transfer in a circular... 相似文献
257.
P. Md. Khaja Mohinuddin Ravikrishna Dada Abdulrahman I. Almansour Natarajan Arumugam Srinivasarao Yaragorla 《Tetrahedron letters》2019,60(15):1043-1048
Diastereoselective, three-component annulation reaction involving glyoxals, anilines and dienophiles is developed under calcium catalysis. When indene is the dienophile, the reaction gave excellent diastereoselectivity to yield tetrahydro-indenoquinolines, these were further aromatized to get indenoquinolines in one-pot. Aryl acetylenes are used as dienophiles to get 2-acyl quinolines in good yields. 相似文献
258.
Manh Tran Dinh Nam Nguyen Dang Abdulrahman Gihad Keyany Moradi Rasoul Babazadeh Houman 《Journal of Thermal Analysis and Calorimetry》2020,140(6):2865-2873
Journal of Thermal Analysis and Calorimetry - Computational modeling was employed to scrutinize the nanomaterial influence of flow patterns and thermal treatment within a porous region.... 相似文献
259.
Gholamreza Bahrami Bahareh Mohammadi Amir Farshchi Golbarg Ghiasi 《Chromatographia》2009,70(1-2):323-327
An accurate and sensitive reversed-phase high-performance liquid chromatographic method for analysis of sertraline in human serum, using 4-chloro-7-nitrobenzofurazan as pre-column derivatization agent, is described. The drug and an internal standard (azithromycin) were extracted from serum by use of a mixture of diethyl ether and chloroform, and subjected to pre-column derivatization with the reagent. Analysis of the resulting derivatives was performed on a 250 mm × 4.0 mm cyano column with 63:37 (v/v) methanol–sodium phosphate buffer (0.05 M, pH 3.7) containing 2 mL L?1 triethylamine as mobile phase. Detector response was monitored at excitation and emission wavelengths of 470 and 537 nm, respectively. The calibration plot was linear over the concentration range 2–640 ng mL?1. The lower limits of detection and quantification were 0.5 and 2 ng mL?1, respectively. The method was validated for specificity, sensitivity, linearity, precision, accuracy, and stability and shown to be accurate (intra-day and inter-day accuracy from 0.3 to 4.2%) and precise (intra-day and inter-day precision from 2.4 to 15.5%). The drug was detected at concentrations as low as 2 ng mL?1 in 0.5 mL serum and the method described can be easily applied to human single-dose pharmacokinetic studies of sertraline. 相似文献
260.
The H2O2/SOCl2 reagent system has been used as a new and efficient reagent for deprotection of thiocarbonyls to carbonyl compounds. The salient features of this protocol are short reaction times, good chemoselectivity, clean reaction profiles, and simple work-up that preclude the use of toxic solvents. 相似文献