The dissipation rate of a Ncwtonian fluid with constant shear viscosity can be shown to include three constituents: dilatation, vorticity, and surface strain. The last one is found to make no contributions to the change of kinetic energy. These dissipation constituents are used to identify typical compact turbulent flow structures at high Reynolds numbers. The incompressible version of the simp...

The Kinetic studies were made of the reactions between triphenylphosphine, dialkyl acetylenedicarboxylates in the presence of NH-acid, such as harman. To determine the kinetic parameters of the reactions, they were monitored by UV spectrophotometery. The second order fits were automatically drawn and the values of the second order rate constant (k2) were calculated using standard equations with...

Thermal electron attachment to the radical species C2F3 and C2F5 has been studied over the temperature range 300-890 K using the Variable Electron and Neutral Density Attachment Mass Spectrometry technique. Both radicals exclusively undergo dissociative attachment to yield F(-). The rate constant for C2F5 shows little dependence over the temperature range, remaining ~4 × 10(-9) cm(3) s(-1). The...

A theoretical study of the kinetic and mechanism of 3-aug-Cope rearrangement in gas phase was performed usingDET methods at B3LYP levels of theory with 6-3114iG(d,p) bass set at 298.I5K. Equilibrium moleculargeometries and harmonic vibrational frequencies of the reactant, transition state Did product were calculated. Then,rate constant and activation thermodynamics parameters were calculated an...

introduction: advanced oxidation processes (aops) suggest a highly reactive, nonspecific oxidant namely hydroxyl radical (oh•), that oxidize a wide range of pollutants fast and non-selective in wastewater and water. materials and methods: in this work, the nitrogen-doped titanium dioxide nanoparticles were primed by sol-gel method, characterized by x-ray diffraction and scanning electron micros...

The kinetic mechanism of the binding and release of calcium by troponin and by the complexes troponin: tropomyosin, troponin:tropomyosin:actin, and troponin (TN)-tropomyosin (TM)-actin:myosin subfraction 1 (SF-1) was investigated using troponin labeled on the TN-I subunit with the fluorophore 4-(N-iodoac etoxyethyl-N-methyl)-7-nitrobenz-2-oxa-1,3-diazole. The apparent association constant is fi...

the solutions of mathematical models for the estimation of the kinetic, and biokinetic parameters of naphthalene, anthracene and pyrene during degradation in surface and subsurface soils are presented in this work. the models were developed using the twin concepts of rate-determining step and steady-state approximation method. they described the biodegradation of single and a mixture of polycyc...

The kinetics of cellulose decomposition in ionic liquid was investigated using microcrystalline cellulose as a raw material. Curve fitting of cellulose degradation kinetic data was carried out by MATLAB. Experimental results demonstrated that the cellulose decomposition rate constant, k1, was less than the constant for glucose decomposition to 5-hydroxymethylfurfural (5HMF), k2, in the ionic li...

We have studied the binding of alpha-bungarotoxin to a particulate fraction of goldfish brain enriched in synaptosomes. The binding is specific and saturable and exhibits the pharmacological properties of a nicotinic cholinergic receptor. Equilibrium binding measurements yield a single dissociation constant (KD) of 0.92 nM. Kinetic analysis revealed one association rate constant and two dissoci...

Formation of natural gas hydrate is a serious problem in the gas and oil industry because it can plug pipelines and destroy the equipment. This study aimes to evaluate the concentration effect of glycol ethers on their synergism with a commercial kinetic hydrate inhibitor (Luvicap 55W) in sweet natural gas-water systems at a constant temperature of 4 oC and pressure of 95 bar. Hydrate formation...