Kinetics of Collision Processes in Dilute Noble Gases

2000 ◽  
Vol 65 (2) ◽  
pp. 141-160
Author(s):  
René Kalus
Keyword(s):  
Noble Gases ◽  
Kinetic Equations ◽  
Small Concentration ◽  
Stationary States ◽  
Dilute Gas ◽  
Reaction Models ◽  
Collision Processes ◽  
Quasiclassical Trajectories ◽  
Chemically Reacting ◽  
Kinetics Of

Kinetics of collision processes is analyzed for dilute noble gases within a linear approximation. Dilute gas is treated as a chemically reacting mixture of dimers and monomers. Two elementary reaction models are analyzed employing theoretical rate constants calculated recently from quasiclassical trajectories. Stability of stationary states and relaxation of small concentration perturbations are treated in terms of linearized kinetic equations. The results obtained are generalized for heavier noble gases (neon to xenon). Helium is, because of quantum nature, analyzed separately.

Reactions of alicyclic ketones in carbon tetrachloride. II. Kinetics of the chlorination of 2-chlorocyclopentanone and 2-chlorocyclohexanone, catalyzed by hydrogen chloride

1986 ◽  
Vol 64 (9) ◽  
pp. 1690-1696 ◽  
Author(s):  
Eize J. Stamhuis ◽  
Henk Maatman ◽  
Geert E. H. Joosten
Keyword(s):  
Carbon Tetrachloride ◽  
Hydrogen Chloride ◽  
Kinetic Equations ◽  
Base Catalysis ◽  
Strong Increase ◽  
Reaction Products ◽  
Reaction Models ◽  
Basic Catalysts ◽  
Self Association ◽  
Kinetics Of

The kinetics of the direct chlorination of 2-chlorocyclopentanone (2-mccp) and 2-chlorocyclohexanone (2-mcch) in carbon tetrachloride, catalyzed by hydrogen chloride, were studied. Reaction products are all the possible 2,2-, 2,5-, and 2,6-dichloro compounds. The ratios depend on the concentrations of the monochloro compound and hydrogen chloride. Surprisingly, even at conversions of the monochloro compound as low as 2%, 2,2,5-trichlorocyclopentanone and 2,2,6-trichlorocyclohexanone, respectively, are also formed. The chlorination reaction of both monochloro ketones shows zero order in chlorine. The order in hydrogen chloride is 1.3. The order in 2-mccp and 2-mcch varies somewhat with the concentration of the ketone and was found to be roughly 1.7. The variation in reaction order is explained by a partial self-association of the ketones. The ketones act as substrates as well as basic catalysts in the rate-determining α- or α′-carbon deprotonation. General base catalysis is clearly demonstrated by a strong increase in the rate of chlorination of 2-mccp upon addition of cyclopentanone (cp) to the reaction mixture, which agrees with the mechanism as presented in a previous paper. Kinetic equations derived from the reaction models for the "separate" and "mixed" ketone chlorinations accurately describe the observed rates of the chlorination of 2-mccp and 2-mcch in the concentration range of 0.04–1.0 M.

The Kinetics of Glucose Decomposition with Sulfate Reduction in the Anaerobic Fluidized Bed Reactor

1993 ◽  
Vol 28 (2) ◽  
pp. 135-144 ◽  
Author(s):  
S. Matsui ◽  
R. Ikemoto Yamamoto ◽  
Y. Tsuchiya ◽  
B. Inanc
Keyword(s):  
Sulfate Reduction ◽  
Fluidized Bed ◽  
Kinetic Equations ◽  
Fluidized Bed Reactor ◽  
Order Reaction ◽  
First Order Reaction ◽  
First Order ◽  
Glucose Decomposition ◽  
Reaction Equations ◽  
Kinetics Of

Using a fluidized bed reactor, experiments on glucose decomposition with and without sulfate reduction were conducted. Glucose in the reactor was mainly decomposed into lactate and ethanol. Lactate was mainly decomposed into propionate and acetate, while ethanol was decomposed into propionate, acetate, and hydrogen. Sulfate reduction was not involved in the decomposition of glucose, lactate, and ethanol, but was related to propionate and acetate decomposition. The stepwise reactions were modeled using either a Monod expression or first order reaction kinetics in respect to the reactions. The coefficients of the kinetic equations were determined experimentally. The modified Monod and first order reaction equations were effective at predicting concentrations of glucose, lactate, ethanol, propionate, acetate, and sulfate along the beight of the reactor. With sulfate reduction, propionate was decomposed into acetate, while without sulfate reduction, accumulation of propionate was observed in the reactor. Sulfate reduction accelerated propionate conversion into acetate by decreasing the hydrogen concentration.

Kinetics of the catalytic hydrodesulphurization reaction system; hydrogenolysis of thiophene

1980 ◽  
Vol 45 (10) ◽  
pp. 2728-2741 ◽  
Author(s):  
Pavel Fott ◽  
Petr Schneider
Keyword(s):  
Atmospheric Pressure ◽  
Active Sites ◽  
Flow Reactor ◽  
Kinetic Equations ◽  
Reaction System ◽  
Reaction Products ◽  
Molybdenum Catalyst ◽  
Cobalt Molybdenum Catalyst ◽  
Kinetics Of ◽  
Reaction Schemes

Kinetics have been studied of the reaction system taking place during the reaction of thiophene on the cobalt-molybdenum catalyst in a gradientless circulation flow reactor at 360 °C and atmospheric pressure. Butane has been found present in a small amount in the reaction products even at very low conversion. In view of this, consecutive and parallel-consecutive (triangular) reaction schemes have been proposed. In the former scheme the appearance of butane is accounted for by rate of desorption of butene being comparable with the rate of its hydrogenation. According to the latter scheme part of the butane originates from thiophene via a different route than through hydrogenation of butene. Analysis of the kinetic data has revealed that the reaction of thiophene should be considered to take place on other active sites than that of butene. Kinetic equations derived on this assumption for the consecutive and the triangular reaction schemes correlate experimental data with acceptable accuracy.

β Grain Growth Kinetics of a New Metastable β Titanium Alloy

2013 ◽  
Vol 747-748 ◽  
pp. 844-849 ◽  
Author(s):  
Yue Fei ◽  
Xin Nan Wang ◽  
Zhi Shou Zhu ◽  
Jun Li ◽  
Guo Qiang Shang ◽  
...  
Keyword(s):  
Titanium Alloy ◽  
Grain Growth ◽  
Kinetic Equations ◽  
Type Equation ◽  
Growth Exponent ◽  
Solution Treated ◽  
Growth Activation ◽  
Grain Growth Kinetics ◽  
Kinetics Of ◽  
Strength And Ductility

Ti-Mo-Nb-Cr-Al-Fe-Si alloy is a new metastable β titanium alloy with excellent combination of strength and ductility. The β grain-growth exponent and the activation energies for β grain growth for the investigated alloy at specified temperature were computed by the kinetic equations and the Arrhenius-type equation. The rate of β grain growth decreases with elongating solution treated time and increases with the increasing solution-treated temperature. The β grain-growth exponents, n, are 0.461, 0.464 and 0.469 at 1113, 1133 and 1153K, respectively. The β grain growth activation energy is determined to be 274 KJ/mol.

scholarly journals Fluoride Leaching of Titanium from Ti-Bearing Electric Furnace Slag in [NH4+]-[F−] Solution

Metals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1176
Author(s):  
Fuqiang Zheng ◽  
Yufeng Guo ◽  
Feng Chen ◽  
Shuai Wang ◽  
Jinlai Zhang ◽  
...  
Keyword(s):  
Activation Energy ◽  
Electric Furnace ◽  
Kinetic Equations ◽  
Surface Chemical ◽  
Leaching Rate ◽  
Surface Chemical Reaction ◽  
Mechanism And Kinetics ◽  
Semi Empirical ◽  
Kinetics Of ◽  
Furnace Slag

The effects of F− concentration, leaching temperature, and time on the Ti leaching from Ti-bearing electric furnace slag (TEFS) by [NH4+]-[F−] solution leaching process was investigated to reveal the leaching mechanism and kinetics of titanium. The results indicated that the Ti leaching rate obviously increased with the increase of leaching temperature and F− concentration. The kinetic equation of Ti leaching was obtained, and the activation energy was 52.30 kJ/mol. The fitting results of kinetic equations and calculated values of activation energy both indicated that the leaching rate of TEFS was controlled by surface chemical reaction. The semi-empirical kinetics equation was consistent with the real experimental results, with a correlation coefficient (R2) of 0.996. The Ti leaching rate reached 92.83% after leaching at 90 °C for 20 min with F− concentration of 14 mol/L and [NH4+]/[F−] ratio of 0.4. The leaching rates of Si, Fe, V, Mn, and Cr were 94.03%, 7.24%, 5.36%, 4.54%, and 1.73%, respectively. The Ca, Mg, and Al elements were converted to (NH4)3AlF6 and CaMg2Al2F12 in the residue, which can transform into stable oxides and fluorides after pyro-hydrolyzing and calcinating.

scholarly journals Kinetics of the active media of nuclear-pumped lasers

1993 ◽  
Vol 11 (4) ◽  
pp. 655-661 ◽  
Author(s):  
A.M. Boichenko ◽  
A.V. Karelin ◽  
O.V. Sereda ◽  
S.I. Yakovlenko
Keyword(s):  
Numerical Simulation ◽  
High Power ◽  
Short Wavelength ◽  
Noble Gases ◽  
Excimer Lasers ◽  
Active Media ◽  
Metal Vapors ◽  
Kinetics Of

Numerical simulation of active media nuclear-pumped lasers on noble gases and their mixtures with metal vapors are presented. Prospects of creation of high-power short-wavelength nuclear-pumped excimer lasers are discussed.

Preliminary Study on Reaction Kinetics of Ammonia Nitrogen in Aqueous Samples Removed by Microbial Nano-Silica Ball

2014 ◽  
Vol 1010-1012 ◽  
pp. 528-531
Author(s):  
Chao Yin ◽  
Jia Lu ◽  
Xiao Hou Shao ◽  
Xin Yu Mao ◽  
Long Wang ◽  
...  
Keyword(s):  
Reaction Kinetics ◽  
Enrichment Culture ◽  
Kinetic Equations ◽  
Culture Liquid ◽  
Ammonia Nitrogen ◽  
Aqueous Samples ◽  
Nano Silica ◽  
N Removal ◽  
Preliminary Study ◽  
Kinetics Of

EM enrichment culture liquid was immobilized on nano-silica carrier to form microbial nano ball, so as to investigate the reaction kinetics of ammonia nitrogen (NH4+-N) by microbial nano ball. The results showed that first order reaction kinetics model could describe NH4+-N removal by different diameter microbial nano-silica balls well. And the microbe could keep higher biological activity between 0-72h. Reaction kinetic equations of NH4+-N were: (1) when diameter was 10mm, (0-48h), (48-72h); (2) when diameter was 20mm, (0-48h), (48-72h); (3) (0-48h), (48-72h).

Vibrational kinetics of the ozone molecule in binary mixtures with noble gases

1999 ◽  
Author(s):  
Olga Y. Nikiforova ◽  
Yurii N. Ponomarev ◽  
Boris A. Tikhomirov ◽  
V. Zeninari ◽  
D. Courtois
Keyword(s):  
Binary Mixtures ◽  
Noble Gases ◽  
Ozone Molecule ◽  
Vibrational Kinetics ◽  
Kinetics Of

Specific features of the population kinetics of levels of noble gases in experiments with a pulsed electron beam

2003 ◽  
Vol 95 (3) ◽  
pp. 333-335
Author(s):  
V. I. Yakovleva ◽  
V. E. Yakhontova ◽  
A. B. Tsyganov ◽  
I. E. Kozlov
Keyword(s):  
Electron Beam ◽  
Noble Gases ◽  
Pulsed Electron Beam ◽  
Population Kinetics ◽  
Kinetics Of

The Characteristics and Kinetics of 4-CP with Pb2+ Biodegradation by Fusarium sp.

2013 ◽  
Vol 726-731 ◽  
pp. 2506-2509
Author(s):  
Xiao Xiao Wang ◽  
Xiao Qin Yu ◽  
Jun Ya Pan ◽  
Ji Wu Li
Keyword(s):  
Carbon Source ◽  
Kinetic Equations ◽  
Order Reaction ◽  
Zero Order ◽  
Biodegradation Rate ◽  
Reaction Equation ◽  
Zero Order Reaction ◽  
Kinetics Of ◽  
Additional Carbon Source

The effects of Pb2+concentration, pH and additional carbon source on biodegradation of 4-chlorophenol (4-CP) byFusariumsp. were investigated, and the characteristic and kinetic of 4-CP biodegradation were analyzed. It was concluded that 4-CP biodegradation rate byFusariumsp. decreased a little at concentration of Pb2+0.20 mg/L and 4-CP 50 mg/L. The suitable biodegradation pH was range from 6 to 7. Additional carbon source (phenol) might increase the rate of 4-CP biodegradation. The kinetic equations of 4-CP biodegradation were well accord with the zero order reaction equation at different concentration of Pb2+.

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