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111.
F Borcan CM Soica S Ganta MM Amiji CA Dehelean O Cerga MF Munteanu 《Chemistry Central journal》2012,6(1):87
ABSTRACT: BACKGROUND: Polymers have been considered as important materials in fabrication of microstructures for various medical purposes including drug delivery. This study evaluates polyurethane as material for hollow microstructures preparation. RESULTS: Polyurethane microstructures were obtained by interfacial polyaddition combined with spontaneous emulsification and present slightly acid pH values. Scanning electron microscopy revealed the existence of irregular shapes and agglomerated microstructures. The material is heat resistant up to 280 [DEGREE SIGN]C. Good results were recorded on murine skin tests in case of polyurethane microstructures based on isophorone diisocyanate. Mesenchymal stem cells viability presents good results for the same sample after 48 hours based on the Alamar Blue test. CONCLUSIONS: The research revealed the reduced noxiousness of this type of microstructures and consequently the possibility of their use for therapeutic purposes. 相似文献
112.
Numerical and analytical solutions of an Oldroyd 8‐constant MHD fluid with nonlinear slip conditions
The flow of an Oldroyd 8‐constant non‐Newtonian MHD fluid is investigated analytically and numerically. The governing equations for the flow field are derived for a steady one‐dimensional flow. The effect of constant applied magnetic field is included and its influence on the flow field is studied. The nonlinear governing equation along with nonlinear boundary conditions is solved analytically and the solution is obtained in an elegant way. Numerical solutions are also obtained using higher order Chebyshev spectral methods. The influence of various non‐Newtonian parameters and applied magnetic field is investigated. Results showing the effect of various physical parameters of the flow are presented and investigated. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
113.
Seraj Faiza Kanwal Khan Khalid Mohammed Khan Ajmal Ali Muhammad Khalil Ruqaiya Ul-Haq Zaheer Hameed Shehryar Taha Muhammad Salar Uzma Perveen Shahnaz 《Molecular diversity》2021,25(1):143-157
Molecular Diversity - Novel ibuprofen derivatives 1–19 including ibuprofen hydrazide 1, and substituted thiourea derivatives 2–19 were synthesized and characterized by EI-MS, FAB-MS,... 相似文献
114.
Hameed Ahmed Khan 《辐射效应与固体损伤》2013,168(2):71-73
The studies regarding the annealing properties of a pre-irradiation annealed Makrofol N track detector showed that under “moderate annealing conditions”, the maximum etched track length lmax, can be increased. The increase becomes maximum at pre- and post-irradiation annealing temperatures of 80°C and 60°C respectively. 相似文献
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W. Aslam Farooq M. Atif Syed Mansoor Ali Amanullah Fatehmulla M. Aslam 《Optics and Spectroscopy》2014,117(3):386-391
TiO2 thin film has been widely used as photoelectrode in dye-sensitized solar cells. It can also be used in quantum dot synthesized solar cells. Study of its effects in different spectrum of light is important for its use in solar cells. We have reported effects of 1064 nm laser on the surface morphology, structural and optical properties of nanostructured TiO2 thin film deposited on glass substrates using sol-gel spin coating technique. Q-Switched Nd:YAG pulsed laser at various power densities is used in this study. Surface morphology of the film is investigated using X-ray diffraction (XRD) and atomic force microscopy technique. The XRD pattern of as deposited TiO2 thin film is amorphous and after laser exposure it became TiO2 anatase structure. Atomic force microscopy of the crystalline TiO2 thin film shows that the grain size increases by increasing laser power density. The calculations of the band gap are carried out from UV/Visible spectroscopy measurements with JASCO spectrometer. For laser power density of 25 MW/cm2 there is an increase in the transmission and it decreases at the value of 38 MW/cm2 and band gap decreases with increasing laser power density. Photoluminescence spectra of the crystalline TiO2 thin film indicate two broad peaks in the range of 415 and 463 nm, one for band gap peak (415 nm) and other for oxygen defect during film deposition process. 相似文献
118.
W. A. Farooq S. Mansoor Ali J. Muhammad S. Danish Ali M. Atif 《Optics and Spectroscopy》2014,116(3):473-478
The effects of laser irradiation on the surface, structure and optical properties of SnO thin films deposited on glass substrates using electron beam evaporation, are investigated. The thin film samples are irradiated using fundamental beam at 1064 nm from Q-switched Nd:YAG pulsed laser with different power densities. Structural morphology of the film is investigated using XRD patterns and AFM image. Both XRD pattern and AFM image show increase in grain size of the film with increasing laser power density. Other optical phenomena, photoluminescence emission, transmission, refractive index determination and optical band gaps calculations are also carried out at various laser power densities. Results from all these investigations reveal expansion in grain size of the crystalline SnO thin film with increasing laser power density. 相似文献
119.
MHD flow of nanofluids over an exponentially stretching sheet in a porous medium with convective boundary conditions 下载免费PDF全文
This article concentrates on the steady magnetohydrodynamic(MHD) flow of viscous nanofluid. The flow is caused by a permeable exponentially stretching surface. An incompressible fluid fills the porous space. A comparative study is made for the nanoparticles namely Copper(Cu), Silver(Ag), Alumina(Al2O3) and Titanium Oxide(TiO2). Water is treated as a base fluid. Convective type boundary conditions are employed in modeling the heat transfer process. The non-linear partial differential equations governing the flow are reduced to an ordinary differential equation by similarity transformations. The obtained equations are then solved for the development of series solutions. Convergence of the obtained series solutions is explicitly discussed. The effects of different parameters on the velocity and temperature profiles are shown and analyzed through graphs. 相似文献
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