A theoretical study on the spectroscopy and the radiative and non-radiative relaxation rate constants of the S01A1–S11A2 vibronic transitions of formaldehyde

Absolute experimental and theoretical rate constants are determined for the first time for the reaction of 3-hydroxy-3-methyl-2-butanone with OH as a function of temperature. The atmospheric implications are discussed.

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THEORETICAL STUDY ON THE ISOMERIZATIONPHOTODECOMPOSITION OF FORMYL CHLORIDE——Theoretical Calculation on Chemical Equilibrium Constants and Kinetical Rate Constants at ab initio Level

Acta Physico-Chimica Sinica ◽

10.3866/pku.whxb19890613 ◽

1989 ◽

Vol 5 (06) ◽

pp. 712-714

Author(s):

Ju Guanzhi ◽

◽

Chen Dezhan ◽

Deng Conghao ◽

Han Jun ◽

...

Keyword(s):

Ab Initio ◽

Theoretical Calculation ◽

Chemical Equilibrium ◽

Rate Constants ◽

Theoretical Study ◽

Equilibrium Constants

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Experimental and Theoretical Study to Optimize Rate Constants of Adsorption and Desorption of the Wastewater Treatment Using Waste of Tea Plant

Arabian Journal for Science and Engineering ◽

10.1007/s13369-019-03896-6 ◽

2019 ◽

Vol 44 (8) ◽

pp. 7361-7370

Author(s):

Ahmmed Saadi Ibrehem

Keyword(s):

Wastewater Treatment ◽

Rate Constants ◽

Theoretical Study ◽

Tea Plant ◽

Adsorption And Desorption

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Theoretical Study of the Iron Complexes with Lipoic and Dihydrolipoic Acids: Exploring Secondary Antioxidant Activity

Antioxidants ◽

10.3390/antiox9080674 ◽

2020 ◽

Vol 9 (8) ◽

pp. 674

Author(s):

Roger Monreal-Corona ◽

Jesse Biddlecombe ◽

Angela Ippolito ◽

Nelaine Mora-Diez

Keyword(s):

Antioxidant Activity ◽

Electron Transfer ◽

Rate Constant ◽

Thermodynamic Stability ◽

Rate Constants ◽

Theoretical Study ◽

Oh Radicals ◽

Single Electron Transfer ◽

Coordination Numbers ◽

Ph Conditions

The thermodynamic stability of twenty-nine Fe(III) complexes with various deprotonated forms of lipoic (LA) and dihydrolipoic (DHLA) acids, with coordination numbers 4, 5 and 6, is studied at the M06(SMD)/6-31++G(d,p) level of theory in water under physiological pH conditions at 298.15 K. Even though the complexes with LA- are more stable than those with DHLA−, the most thermodynamically stable Fe(III) complexes involve DHLA2−. The twenty-four exergonic complexes are used to evaluate the secondary antioxidant activity of DHLA and LA relative to the Fe(III)/Fe(II) reduction by O2•− and ascorbate. Rate constants for the single-electron transfer (SET) reactions are calculated. The thermodynamic stability of the Fe(III) complexes does not fully correlate with the rate constant of their SET reactions, but more exergonic complexes usually exhibit smaller SET rate constants. Some Cu(II) complexes and their reduction to Cu(I) are also studied at the same level of theory for comparison. The Fe(III) complexes appear to be more stable than their Cu(II) counterparts. Relative to the Fe(III)/Fe(II) reduction with ascorbate, DHLA can fully inhibit the formation of •OH radicals, but not by reaction with O2•−. Relative to the Cu(II)/Cu(I) reduction with ascorbate, the effects of DHLA are moderate/high, and with O2•− they are minor. LA has minor to negligible inhibition effects in all the cases considered.

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