In this study, we elucidate the reaction kinetics for simultaneous hydrodeoxygenation of xylitol to 1,2-dideoxypentitol and 1,2,5-pentanetriol over a ReOx-Pd/CeO2 (2.0 weight% Re, 0.30 Pd) catalyst. The was determined be zero-order with respect xylitol. activation energy elucidated through an Arrhenius relationship as well non-Arrhenius kinetics. investigated at 150–170 °C constant H2 pressure ...

An efficient design of in situ combustion depends on accurate kinetic modeling of the crude oil oxidation. The kinetic triplet of the oxidation reactions of a heavy oil sample was investigated. Once the kinetic triplet is known, the kinetic equation would be deconvolved. The crude oil sample was obtained from Kuh-E-Mond reservoir, located in the southwest of Iran. The samples were analyzed usin...

The hindered internal rotations around the partial carbon-carbon double bond, nitrogen-carbon and carbon-carbon single bonds within the 2-(2-chloro-phenothiazine-l-yl)-3-(triphenylphosphoranylidene) butandioate has been experimentally studied by the dynamic H NMR spectroscopic in variable temperatures. The activation (∆H, ∆S, ∆G) and kinetic (kc, Ea) parameters have been calculated in a series ...

The characteristic relaxation time τ of protein hydration water exhibits a strong hydration level h dependence. The dynamic crossover is observed when h is higher than the monolayer hydration level hc=0.2-0.25 and becomes more visible as h increases. When h is lower than hc, τ only exhibits Arrhenius behavior in the measured temperature range. The activation energy of the Arrhenius behavior is ...

This paper draws attention to selected experiments on enzyme-catalyzed reactions that show convex Arrhenius plots, which are very rare, and points out that Tolman's interpretation of the activation energy places a fundamental model-independent constraint on any detailed explanation of these reactions. The analysis presented here shows that in such systems, the rate coefficient as a function of ...

The rate of desorption of chemisorbed chlorobenzene molecules from the Si(111)-7 × 7 surface, induced by nonlocal charge injection from an STM tip, depends on the surface temperature. Between 260 and 313 K, we find an Arrhenius thermal activation energy of 450 ± 170 meV, consistent with the binding energy of physisorbed chlorobenzene on the same surface. Injected electrons excite the chlorobenz...

energy and mass transfer investigations in thermal processing of fruits serve as a breakthrough in the design and scale up of drying systems. diffusivity characteristics and specific energy consumption for drying of fig fruit in a laboratory scale microwave dryer were assessed. several intervals for microwave power intensity including 0.5, 1, 1.5, 2, and 2.5 w g-1, and 6 levels of power on-off ...

jujube (zizyphus jujube mill), a valuable medicinal plant, is consumed either as fresh fruit or dried product in iran. drying jujube guarantees a longer shelf time while preserving its quality to be used in medical and pharmaceutical industries. in this research paper, the influence of several drying conditions on the effective moisture diffusivity, activation energy, energy consumption and req...

The activities of acetylcholinesterase (ACHE) and butyrylcholinesterase (BuChE) in rat brain capillaries were measured as a function of temperature. Arrhenius plots of the data revealed that AChE exhibits a biphasic Arrhenius plot with a distinct break (transition temperature) at about 15.2 kcal/mol. In contrast, BuChE did not show evidence of discontinuity. BuChE showed an activation energy hi...

a palladium composite membrane was prepared via electroless plating technique using organic-inorganic method during activation process. the ceramic support surface was modified by two tio2-boehmite and one γ-alumina layers to avoid pd penetration in support pores. thin and defect-free pd composite membrane was obtained by creating a relative smoothness on the ceramic support and using pd nanopa...