S-doped and bare mesoporous TiO2 were prepared using titanium tetraisopropoxide and thiocarbamide as raw materials. Prepared materials were characterized by means of fourier transform infrared spectroscopy FT-IR, thermogravimetry-differential scanning calorimetry (TG-DSC), X-ray diffraction (XRD), UV–Vis absorption spectroscopy, Brunauer–Emmett–Teller (BET) specific surface area and Barrett–Joyner–Halenda (BJH) pore size distribution analyses, scanning electron microscopy (SEM) and Energy-dispersive […]
Protonation of the highly reactive 1:1 intermediates, produced in the reaction between triphenylphosphine and acetylenic esters, by NH-acids such as azathioprine, imidazole or theophylline leads to the formation of vinyltriphenylphosphonium salts, which undergo a Michael addition reaction with a conjugate base to produce phosphorus ylides. Silica nanoparticles (silica NPs were prepared by thermal decomposition of […]
A relationship based on the modified couple stress theory is developed to investigate the flexural sensitivity of an atomic force microscope (AFM) with assembled cantilever probe (ACP). This ACP comprises a horizontal cantilever, two vertical extensions and two tips located at the free ends of the extensions which form a caliper. An approximate solution to […]
Research in convective heat transfer using suspensions of nanometer-sized solid particles in base liquids started only over the past decade. Recent investigations on nanofluid, as such suspensions are often called, indicate that the suspended nanoparticles remarkably change the transport properties and heat transfer characteristics of the suspension. Bending walls can also improve heat transfer by […]
Dipolar-dephasing method provides some information about the strength of dipolar coupling in solids. Dipolar dephasing technique measures the time for a polarized carbon nucleus to lose its magnetization once the proton locking field is terminated. The dynamics of guest molecules adsorbed within the cavities and channels of nonporouszeolite strongly depend on the structure and chemical […]
In this study, the adsorption of 1-chloro-4-nitrobenzene (1C4NB) on carbon nanofibers (CNFs), was investigated in a batch system. The combined effects of operating parameters such as contact time, pH, initial 1C4NB concentration, and CNFs dosage on the adsorption of 1C4NB byCNFs were analyzed using response surface methodology (RSM). The analysis of variance results confirmed that […]
In the present work, a prototype of a new type of solar collectors, which called Direct Absorption Solar Collector, was built and its thermal performance is experimentally compared with conventional flat plate solar collector under transient and steady state conditions. Different volume fractions of multi wall carbon nanotubes in water and ethylene glycol mixture (70%:30% […]
This paper reports the synthesis and characterization of photocatalyst CdS nanoparticles for investigation of photocatalytic degradation of 2,4,6-trichlorophenol. CdS nanoparticles were synthesized by the microwave-assisted sol-gel method and characterized by various techniques such as X-ray diffraction, filed emission scanning electron microscopy, energy dispersive spectroscopy, Fourier transform infrared spectroscopy and UV-visible spectrophotometer. The average crystallite size […]
In this work, hierarchical WO3 core-shell microspheres were synthesized via a facile template-free precipitation method. Gas sensing properties of the synthesized powder to acetone and some other volatile organic compounds were comparatively investigated with commercial WO3 nanoparticles. The synthesized and commercial powders were characterized by X-ray diffraction, scanning electron microscopy, particle size distribution analysis, Brunauer–Emmett–Teller […]
Adsorption of CO2 on the surface of Single-wall zigzag (5,0) and armchair (4,4) carbon nanotubes (SWCNTs) were studied through using density functional theory (DFT) calculations. Optimizations of geometric were performed at the B3PW91 level of 6-311++G** method standard basis set using GAUSSIAN 03 package of program [1]. Structural models were optimized and adsorption energies, band […]
