Coverage-dependent sticking probabilities and second-order rate constants for recombinative desorption of hydrogen from Rh( 111 ) have been measured using molecular beam relaxation spectroscopy (MBRS) and time-resolved specular helium scattering. The sticking probability follows second-order Langmuir coverage dependence, with So equal to 0.01 ___ 0.005. Under isothermal and nearly isosteric con...

dose-dependent pharmacokinetic of phenytoin necessitates the estimation of the maximum rate of metabolism (vm) and the michaelis-menten constant (km) in a concerned population. the aim of this study was to determine the pharmacokinetic parameters of phenytoin in a sample of iranian patients to optimize the antiepileptic pharmacotherapy. fourty patients who received a constant dose of phenytoin ...

water alternating gas (wag) technique is used in the petroleum industry to inject carbon dioxide (co2) into underground formations either for sequestration or enhanced oil recovery (eor) processes. co2 injection causes reactions with formation brine or aquifer and produces carbonic acid, the acid dissolves calcite and changes flow behavior significantly. modeling and investigating effects of co...

In this work the kinetics of a number of sulfide-oxidizing nitrate-reducing (SO-NR) cultures acclimated and not acclimated to nitrite were characterized. Anoxic respirometry coupled to kinetic modeling of respirometric profiles was the methodology used to study the two-step denitrification associated to thiosulfate oxidation. Autotrophic denitritation was initially studied in a non-acclimated S...

in this study, the turbulent kinetic energy redistribution process is investigated. to this aim, the direct numerical simulation (dns) of incompressible flow of a newtonian fluid through a channel at a shear reynolds number of reτ = 180 is used to produce a flow data base. then, these data are statistically analyzed. the turbulent kinetic energy redistribution is studied using the pressure-stra...

Competitive kinetic experiments utilising free radical carbonylation chemistry provide a first estimate for the rate constant for 6-endo cyclization of the 6-aza-7-ethyl-5-hexenoyl radical of (4.8 +/- 2.4) x 10(6) s(-1) at 90 degrees C in benzene, in good agreement with ONIOM-G3(MP2)-CC+COSMO-RS calculations (6.8 x 10(6) s(-1)).

background and objectives: lactobacillus delbrueckii ssp bulgaricus is widely used in dairy industries as a starter for yogurt production. this study was designed using response surface methodology (rsm) in 12 batch ph-controlled cultures of lactobacillus delbrueckii sub-ssp. bulgaricus for determining the effect of temperature and ph on the biomass production of a native strain of l. bulgaricu...

Biodesulfurization of coal has been carried out in batch culture of single strain and mixed culture of sulfur oxidizing bacteria. The pure cultures of Thiobacillus thiooxidans and Thiobacillus ferrooxidans utilized inorganic sulfur content of Malaysian coal. The chemolithotroph bacteria were able to grow on coal and metabolize the coal's sulfur content. The batch cultures of coal with 3-5 perce...

Chara corallina class XI myosin is by far the fastest molecular motor. To investigate the molecular mechanism of this fast movement, we performed a kinetic analysis of a recombinant motor domain of Chara myosin. We estimated the time spent in the strongly bound state with actin by measuring rate constants of ADP dissociation from actin.motor domain complex and ATP-induced dissociation of the mo...

Kinetic and equilibrium isotope effects in peptide group hydrogen exchange reactions were evaluated. Unlike many other reactions, kinetic isotope effects in amide hydrogen exchange are small because exchange pathways are not limited by bond-breaking steps. Rate constants for the acid-catalyzed exchange of peptide group NH, ND, and NT in H2O are essentially identical, but a solvent isotope effec...