نتایج جستجو برای: desorption kinetic
تعداد نتایج: 107828 فیلتر نتایج به سال:
Time-of-flight distributions of neutral molecules ejected from various organic surfaces have been measured subsequent to 8 keV Ar+ and H2+ ion bombardment. The distributions show that depending on the physical and chemical nature of the substrate, the neutral molecules have strikingly different desorption profiles. For C6H6/Ag¿111¿, at low coverage the C6H6 molecules eject with energies in the ...
Laser-induced desorption of metal atoms at low rate has been studied for pulsed excitation with wavelengths of j"266, 355, 532 and 1064 nm. For this purpose sodium adsorbed on quartz served as a model system. The detached Na atoms were photo-ionized with the light of a second laser operating at j"193 nm and their kinetic energy distribution was determined by timeof-flight measurements. For j"10...
Tetraethylenepentamine (TEPA)-based mesoporous MCM-41 is used as the adsorbent to determine the CO2 desorption kinetics of amine-modified materials after adsorption. The experimental data of CO2 desorption as a function of time are derived by zero-length column at different temperatures (35, 50, and 70 ◦C) and analyzed by Avrami’s fractional-order kinetic model. A new method is used to distingu...
The coadsorption of H 2 and D 2 on Ru(0001) has been studied by thermal programmed desorption. An inverse kinetic isotope effect comparing H2, HD and D 2 desorption has been observed with D 2 desorption being most rapid for temperatures above 350 K. This effect is attributed to a normal isotopic enhancement of H(ads) penetration into subsurface sites on Ru(0001) during the rapid temperature ris...
This work aims to investigate the competitive time-dependent desorption rate of heavy metals (lead, zinc, nickel) coexisting with phenanthrene from natural high buffering soil. Two non-ionic surfactants (Tween 80 and Brij 35) combined with disodium ethylene diamine tetraacetate salt (Na2-EDTA) were utilized as the reagents. The contaminants’ time-dependent desorption data was fitted with five k...
Recent experimental results about the formation of molecular hydrogen on astrophysically relevant surfaces under conditions close to those encountered in the interstellar medium are analyzed using rate equations. The parameters of the rate equation model are fitted to temperature-programmed desorption curves obtained in the laboratory. These parameters are the activation energy barriers for ato...
The desorption yields of excited hydrogen atoms from the surfaces of KCl, KBr, NaCl, NaF, and LiF have been measured as a function of incident photon and electron energy and flux, time of irradiation, dosing pressure of H2 and sample temperature. As these surfaces are exposed to H2 gas during electron or photon bombardment, the fluorescence from excited hydrogen atoms ejected from the surface i...
hydrothermal synthesis of nickel-chitosan hybrid has been accomplished using ni(ch3coo)2,4h2o, chitosan and water as starting material, template and solvent respectively, followed by calcination at 800 and 900˚c to provide nanoporous nio800 and nio900. the solid products were characterized by x-ray diffraction (xrd), nitrogen adsorption-desorption, scanning electron microscopy (sem) and four...
This study reports a preparation method of a new moisture swing sorbent for CO2 capture from air. The new sorbent components include ion exchange resin (IER) and polyvinyl chloride (PVC) as a binder. The IER can absorb CO2 when surrounding is dry and release CO2 when surrounding is wet. The manuscript presents the studies of membrane structure, kinetic model of absorption process, performance o...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید