A method for the direct determination of the rate constants for radical-radical interactions in the gas phase II. The rate constant for the recombination of methyl radicals

1957 ◽  
Vol 243 (1232) ◽  
pp. 130-142 ◽  
Keyword(s):  
Gas Phase ◽  
Rate Constant ◽  
Room Temperature ◽  
Direct Determination ◽  
Theoretical Interpretation ◽  
Methyl Radicals ◽  
Gas Phase Reactions ◽  
A Value ◽  
Acetone Vapour

The technique outlined in part I of this paper has been employed to study the photo­sensitized decomposition of acetone vapour. A theoretical interpretation of the non-stationary state applied to non-chain photochemical gas phase reactions with second-order termination has been given and the effects of non-homogeneous absorption of radiation have been considered. A value has been obtained for the rate constant for the recombination of methyl radicals in the gas phase at room temperature.

A method for the direct determination of the rate constants for radical-radical interactions in the gas phase I. The technique of investigation

1957 ◽  
Vol 243 (1232) ◽  
pp. 119-129 ◽  
Keyword(s):  
Time Delay ◽  
Phase I ◽  
Gas Phase ◽  
Direct Determination ◽  
Pressure Change ◽  
Gas Phase Reactions ◽  
Temperature Changes ◽  
Pressure Changes ◽  
Better Than

A method of following the non-stationary state in simple photochemically initiated gas-phase reactions is described. Measurements are recorded by observing the pressure change occurring in the gas resulting from the adiabatic temperature changes caused by reaction. The pressure changes are observed by means of a sensitive diaphragm type manometer, whose sensitivity in detection is better than 10 -4 mm Hg and whose time delay in response is less than 10 -3 s.

The Reaction of the Electronically Excited Oxygen Atom O(1D2) with Nitrous Oxide

1971 ◽  
Vol 49 (11) ◽  
pp. 1808-1817 ◽  
Author(s):  
P. M. Scott ◽  
K. F. Preston ◽  
R. J. Andersen ◽  
L. M. Quick
Keyword(s):  
Oxygen Atom ◽  
Gas Phase ◽  
Room Temperature ◽  
Flash Photolysis ◽  
Excited Atom ◽  
Total Rate ◽  
A Value ◽  
Electronically Excited ◽  
Excited Oxygen

An investigation has been made of the relative importance of the possible pathways [2a]–[2d][Formula: see text]for the reaction in the gas phase at room temperature between the excited oxygen atom O(1D2) and N2O, using the photolysis of NO2, O3, and N2O as sources of the excited atom. Measurement of the yields of N2 and NO from the photolysis at 2288 Å of mixtures of NO2 and N2O has led to a value of 1.01 ± 0.06 for k2a/k2b, the ratio of the rate constants for [2a] and [2b], in excellent agreement with the value of 0.99 ± 0.06 obtained from determination of the yields of N2 and NO2 arising from the flash photolysis of O3–N2O mixtures. The isotopic composition of the N2 produced in the photolysis of 15NO2–N2O mixtures indicated that k2c/k2a < 5 × 10 – 3. Furthermore, the value of k2a/(k2b + k2d) = 1.08 ± 0.19, obtained from a study of the effect of CO2 and Xe additions on the yield of N2 from the photolysis of N2O at 2288 Å, suggests that deactivation [2d] does not make an important contribution to the total rate constant for destruction of O(1D2).

A New Method for Direct Determination of the Recoilless Fraction with Application to Magnetic Nanoparticles

2002 ◽  
Vol 721 ◽  
Author(s):  
Monica Sorescu
Keyword(s):  
Room Temperature ◽  
Average Particle Size ◽  
Direct Determination ◽  
Average Particle ◽  
Lattice Method ◽  
Recoilless Fraction ◽  
Single Room ◽  
Magnetite Particles ◽  
Physical Mixtures

AbstractWe propose a two-lattice method for direct determination of the recoilless fraction using a single room-temperature transmission Mössbauer measurement. The method is first demonstrated for the case of iron and metallic glass two-foil system and is next generalized for the case of physical mixtures of two powders. We further apply this method to determine the recoilless fraction of hematite and magnetite particles. Finally, we provide direct measurement of the recoilless fraction in nanohematite and nanomagnetite with an average particle size of 19 nm.

Direct determination of the rate constant for the reaction CO + N2O → CO2 + N2

1985 ◽  
Vol 122 (5) ◽  
pp. 489-492 ◽  
Author(s):  
Nobuyuki Fujii ◽  
Tomohisa Kakuda ◽  
Takeo Sugiyama ◽  
Hajime Miyama
Keyword(s):  
Rate Constant ◽  
Direct Determination

An experimental study of the reactivity of the hydroxide anion in the gas phase at room temperature, and its perturbation by hydration

1981 ◽  
Vol 59 (11) ◽  
pp. 1615-1621 ◽  
Author(s):  
Scott D. Tanner ◽  
Gervase I. Mackay ◽  
Diethard K. Bohme
Keyword(s):  
Experimental Study ◽  
Proton Transfer ◽  
Gas Phase ◽  
Rate Constants ◽  
Room Temperature ◽  
Gas Phase Reactions ◽  
Flowing Afterglow ◽  
Hydroxide Anion

Flowing afterglow measurements are reported which provide rate constants and product identifications at 298 ± 2 K for the gas-phase reactions of OH− with CH3OH, C2H5OH, CH3OCH3, CH2O, CH3CHO, CH3COCH3, CH2CO, HCOOH, HCOOCH3, CH2=C=CH2, CH3—C≡CH, and C6H5CH3. The main channels observed were proton transfer and solvation of the OH−. Hydration with one molecule of H2O was observed either to reduce the rate slightly and lead to products which are the hydrated analogues of the "nude" reaction, or to stop the reaction completely, k ≤ 10−12 cm3 molecule−1 s−1. The reaction of OH−•H2O with CH3—C≡CH showed an uncertain intermediate behaviour.

New method for determination of heats of thermal gas-phase reactions yielding intermediates

1996 ◽  
Vol 45 (1) ◽  
pp. 56-59
Author(s):  
N. N. Buravtsev ◽  
Yu. A. Kolbanovskii ◽  
A. A. Ovsyannikov
Keyword(s):  
Gas Phase ◽  
New Method ◽  
Gas Phase Reactions

Gas-phase reactions of nitric oxide with atomic lanthanide cations: Room-temperature kinetics and periodicity in reactivity

2006 ◽  
Vol 249-250 ◽  
pp. 385-391 ◽  
Author(s):  
Voislav Blagojevic ◽  
Eric Flaim ◽  
Michael J.Y. Jarvis ◽  
Gregory K. Koyanagi ◽  
Diethard K. Bohme
Keyword(s):  
Nitric Oxide ◽  
Gas Phase ◽  
Room Temperature ◽  
Gas Phase Reactions ◽  
Lanthanide Cations

scholarly journals The HNO− radical anion: A proposed intermediate in diazeniumdiolate synthesis using nitric oxide and alkoxides

2018 ◽  
Vol 25 (1) ◽  
pp. 82-85 ◽  
Author(s):  
Zhe-Chen Wang ◽  
Ya-Ke Li ◽  
Sheng-Gui He ◽  
Veronica M Bierbaum
Keyword(s):  
Nitric Oxide ◽  
Reaction Mechanism ◽  
Gas Phase ◽  
Radical Anion ◽  
Room Temperature ◽  
Hydrogen Transfer ◽  
Gas Phase Reactions ◽  
Ionic Product

The strategy of synthesizing diazeniumdiolates (X–N(O)=NO−) through the coexistence of nitric oxide and alkoxides (RO−) was introduced by Wilhelm Traube 120 years ago. Today, despite the wide use of diazeniumdiolate derivatives to release nitric oxide in the treatment of cancer, the first step of the reaction mechanism for diazeniumdiolate synthesis remains a mystery and is thought to be complex. We have studied the gas-phase reactions of nitric oxide with alkoxides at room temperature. An electron-coupled hydrogen transfer is observed, and the radical anion HNO− is the only ionic product in these reactions. HNO− can further react with nitric oxide to form N2O and HO−.

Sign in / Sign up

Export Citation Format

Share Document