In this paper the kinetics of the pozzolanic reaction between lime (calcium hydroxide) and sugar cane straw ash with 20 and 30% of clay burned at 800 and 10000C is studied. A simple experimental technique where the conductivity is the experimental variable was used. A calibration curve was established for correlating the conductivity with the concentration of calcium hydroxide (CH). We elaborat...

The reversibility of the NAD+ kinase reaction was established, and the kinetic parameters of the rate equation in the reverse direction were determined. The equilibrium constant of the reaction was determined by using the purified pigeon liver enzyme and radioactively labelled nicotinamide nucleotides. The relationship between kinetic parameters of the forward and reverse reactions is in reason...

Using high-resolution direct numerical simulation and arguments based on the kinetic energy flux Π(u), we demonstrate that, for stably stratified flows, the kinetic energy spectrum E(u)(k)∼k(-11/5), the potential energy spectrum E(θ)(k)∼k(-7/5), and Π(u)(k)∼k(-4/5) are consistent with the Bolgiano-Obukhov scaling. This scaling arises due to the conversion of kinetic energy to the potential ener...

Leaching of molybdenite concentrate with hydrogen peroxide in sulfuric acid solution was investigated to determine the effects of reaction time, reaction temperature, H2O2 concentration, H2SO4 concentration, pulp density and rotation speed on molybdenum extraction and molybdenite dissolution kinetics, using the Taguchi method. From analysis of var...

Palm kernel fibre is a common agricultural waste in West Africa and its use as an adsorbent for the removal of copper ions from aqueous solution has been studied. Batch kinetics studies were carried out based on the assumption of the pseudo-second-order kinetic model, which was developed to predict the rate constant of adsorption, the equilibrium adsorption capacity and initial adsorption rate ...

Active carbon (surface area, 1250 m/g) was used to study vapor breakthrough behavior of sulphur mustard (2, 2’dichlorodiethyl sulphide). Effect of length of carbon bed on vapor breakthrough time has been examined. Rate constant (k v ) is found to increase while kinetic saturation capacity (W e ) is invariable with increase in airflow rate. Both k v and W e decrease with the increase of temperat...

A differential-scanning-calorimetric study of the thermal denaturation of a sea-anemone (Radianthus macrodactylus) 8 kDa cytolytic toxin was carried out. The calorimetric traces were found to be irreversible and scan-rate-dependent under the experimental conditions employed. Scan-rate-dependent thermograms were explained in terms of a two-state kinetic model N k -->D, where k is a first-order k...

The rate constant for the C6H5 + C6H5 recombination reaction has been determined in the temperature range 300-500 K using a laser photolysis/mass spectrometric technique. The result is represented by k1 ) (1.39 ( 0.11) × 1013e-(56(36)/T cm3/(mol s). In addition, the rate constant for the C6H5 + C6H5NO association reaction was found to be k4 ) (4.90 ( 0.19) × 1012e(34(16)/T cm3/(mol s) by the ma...

Biopersistence is a function of different parameters: low solubility of the vitreous phase in physiological media, good mechanical properties of altered fibers, limited ability of phagocytosis to digest residual fragments. This article emphasizes solubility problems. From studies related to nuclear waste storage and other industrial problems, the mechanisms (formation of a leached layer of vari...

Electron transfer within rat neuronal nitric-oxide synthase (nNOS) was investigated by pulse radiolysis. Radiolytically generated 1-methyl-3-carbamoyl pyridinium (MCP) radical was found to react predominantly with the heme of the enzyme with a second-order rate constant for heme reduction of 3 x 10(8) m(-1) s(-1). In the calmodulin (CaM)-bound enzyme a subsequent first-order phase was observed ...