A thermophilic bacillus with minimal, optimal, and maximal growth temperatures of 40, 64.5, and 72 C, respectively, was isolated from soil. Biochemical and morphological studies place the isolate in group 1 of the classification of Walker and Wolf. After adaption to nitrate broth, the temperature coefficient for growth was found to be 20,400 cal/mol. When the temperature coefficient for growth ...

Low-temperature oxidation of aqueous magnetite nanoparticles to maghemite has been monitored via the loss of near-IR optical absorbance. The kinetics closely follows the diffusion in a sphere model as suggested by previous literature reports. The temperature dependence of the diffusion constant is described by an Arrhenius equation with an activation energy of 21.0 kcal/mol. No intermediate opt...

Thermogravimetric studies of chitin and chitosan in air atmosphere were carried out at six rates of linear increase of the temperature. The kinetics and mechanism of the thermal decomposition reaction were evaluated from the TG data using recommended from ICTAC kinetics committee isoconversional calculation procedure of Kissinger-Akahira-Sunose, as well as 27 mechanism functions. The values of ...

Expected lifetime and reliability of multilayer ceramic actuators were considered. 5 · 5 · 5 mm sized multilayer ceramic actuators with 60 ceramic sheet layers embedded internal electrodes were selected in this experimental analysis. Specially selected rectified AC bias was applied to the multilayer ceramic actuators to remove heating during charging and discharging process. Sixteen sets of mul...

Golgi-membrane vesicle penetration was studied by osmotic lysis. Pronounced temperature dependence of mannitol and mannoheptitol penetration over 0-37 degrees C gave linear Arrhenius plots, with activation energies of 75 and 117 kJ/mol respectively. Glucose penetration was constant over pH 5-9, but was respectively faster and slower at higher and lower pH values. Solubilized, dialysed, heat-sta...

In accelerated life testing, the nominal life time is often related to stress levels by an acceleration equation. Three particular models that have been used frequently in the past are the power law model, the Arrhenius model and the Eyring model. In this paper we suggest choosing a model from a model family which includes the three particular models as special cases. This family is deened by a...

Acidophilic iron-oxidizing bacteria were enriched from mine water samples with ferrous sulfate as the substrate at incubation temperatures in the range of 4 to 46 degrees C. After several subcultures at each test temperature except 46 degrees C, which was prohibitive to growth, the rates of iron oxidation were determined in batch cultures. The results yielded linear rates in a semilogarithmic s...

Introduction: Diffusion in brain tissue is well known to be non-Gaussian, resulting in major efforts to understand the biophysical basis of water mobility in such tissues [1]. This study aims to understand the energetics of differently diffusing components by quantification of their respective activation energies. When temperature is varied, self-diffusion in pure liquids follows the Arrhenius ...