in this study, mass transfer coefficients (mtc’s) of natural gas components during hydrate formation are reported. this work is based on the assumption that the transport of gas molecules from gas phase to aqueous phase is dominant among other resistances. several experiments were conducted on a mixture of natural gas at different pressures and temperatures and the consumed gas was monitored an...

A new spectrofluorimetric assay for the photodegradation products of the ansiolytic drug alprazolam is described. Alprazolam was found to be highly photolabile and special care should be taken to avoid light exposure during alprazolam storage and handling. The photostability of alprazolam was evaluated at pH 2.0, 3.6 and 5.0. The drug was exposed to UVA-UVB radiations, the photodegradation of a...

1. The authors fail to distinguish adequately between photodegradation, in which bilirubin is degraded to substances of lower molecular weight, and photoisomerization, in which the pigment’s structure changes but no degradation occurs. Both processes contribute to the effects of phototherapy in humans, but their relative contributions are presently unknown. However, in the Gun rat animal model ...

Cerium oxide and mixed Cu/Ce oxide nanoparticles were prepared by the oil-in-water (O/W) microemulsion reaction method in mild conditions. The Cu/Ce molar ratio was varied between 0/100 and 50/50. According to X-ray diffraction (XRD), below 30/70 Cu/Ce molar ratio, the materials presented a single phase consistent with cubic fluorite CeO₂. However, above Cu/Ce molar ratio 30/70, an excess monoc...

Heat transfer phenomena in batch fluidized bed dryer have been studied and analyzed using three phase model including solid phase, interstitial gas phase and bubble phase based on Rizzi model. New correlations of heat transfer coefficient to surrounding and convection heat transfer coefficient between solid and interstitial gas are being proposed. In addition, some modifications have been d...

this study aimed to construct the hydrate three-phase equilibrium curves for two typical iranian gas reservoir samples using a high-pressure visual cell. to do so, complete analysis of the reservoir fluids was obtained by different techniques of composition analysis i.e. gas chromatography (gc) and detailed hydrocarbon analysis (dha). using high-pressure visual cell the hydrate phase equilibriu...

Herewith we report a facile synthesis of zinc oxide doped with (5, 10, 15 and 20 wt%) titanium nanocomposites in gelatin under ultra-sonication. The X-ray diffraction (XRD) data revealed the ZnO formation addition to rutile TiO2 phase. phase size decreased, while increased loading increment. scanning electron microscopy (SEM) displayed combination spherical hexagonal particles 60–80 nm distribu...