Complete heterogeneously photocatalyzed transformation of 1,1- and 1,2-dibromoethane to carbon dioxide and hydrogen bromide

1984 ◽  
Vol 88 (16) ◽  
pp. 3386-3388 ◽  
Author(s):  
T. Nguyen ◽  
D. F. Ollis
Keyword(s):  
Carbon Dioxide ◽  
Hydrogen Bromide

Radiolysis of aqueous 2,2,2-tribromoethanol solutions

1970 ◽  
Vol 48 (16) ◽  
pp. 2542-2548 ◽  
Author(s):  
V. G. Sorensen ◽  
V. M. Bhale ◽  
K. J. McCallum ◽  
R. J. Woods
Keyword(s):  
Carbon Dioxide ◽  
Dose Rate ◽  
Glycolic Acid ◽  
Hydrogen Bromide ◽  
Photochemical Decomposition ◽  
Bromide Ion ◽  
Presence And Absence ◽  
Effect Of Oxygen

Hydrogen bromide, glycolic acid, and carbon dioxide have been identified as products of the γ-radiolysis of aqueous 2,2,2-tribromoethanol solutions. The effect of oxygen, tribromoethanol concentration, and dose rate upon the yields of bromide ion and acid have been determined, and partial radiolysis mechanisms are proposed for reaction in the presence and absence of oxygen. Dibromoacetaldehyde, reported to be a product of the photochemical decomposition of tribromoethanol solutions, was not detected in the radiolysis experiments or in tribromoethanol solutions exposed to sunlight.

DETERMINATION OF RATES OF CHANGE OF POLARIZABILITY FROM RAMAN AND RAYLEIGH INTENSITIES

1953 ◽  
Vol 31 (6) ◽  
pp. 954-961 ◽  
Author(s):  
E. J. Stansbury ◽  
M. F. Crawford ◽  
H. L. Welsh
Keyword(s):  
Carbon Dioxide ◽  
Hydrogen Chloride ◽  
Internuclear Distance ◽  
Hydrogen Bromide ◽  
Rate Of Change ◽  
Mean Values ◽  
Rates Of Change

Mean values of the rate of change of polarizability with respect to internuclear distance were determined for several molecules from the ratio of Raman and Ray-leigh intensities in the gas. The values obtained are: hydrogen, 1.2 × 10−16 cm.2; deuterium, 1.1; hydrogen chloride, 1.0; hydrogen bromide, 1.2; nitrogen, 1.6; oxygen, 1.4; carbon dioxide (ν1 vibration), 4.2; methane (ν1 vibration), 4.1. It is noteworthy that the values for the partially ionic molecules, hydrogen chloride and hydrogen bromide, are nearly the same as for hydrogen and deuterium.

The oxidation of iso butene catalyzed by hydrogen bromide

1962 ◽  
Vol 268 (1334) ◽  
pp. 405-423 ◽  
Keyword(s):  
Carbon Dioxide ◽  
Carbon Monoxide ◽  
Double Bond ◽  
Small Proportion ◽  
Main Chain ◽  
Hydrogen Bromide ◽  
Inert Gas ◽  
Static System ◽  
Peroxy Radicals ◽  
Methyl Group

The oxidation of iso butene catalyzed by hydrogen bromide in a static system between 100 and 200 °C has been investigated. In a boric oxide coated vessel below about 170 °C the pressure decreased continually during the reaction, the rate accelerating rapidly to a maximum and then falling gradually and the main products being BrCH 2 .C(CH 3 ) 2 .OOH and a diperoxide. The reaction ceased after only a small proportion of the olefin was oxidized owing to the HBr being used up. At 145 °C ρ max. ∝ [C 4 H 8 ] 0.35 [O 2 ] 0.5 [HBr] 1.76 . Added inert gas or packing the vessel had little effect on the rate, but the reaction was accelerated by added bromine, t .-butyl hydroperoxide and di- t .-butylperoxide and retarded by added alcohols. At 195 °C the pressure decreased to a minimum and then rose, most of the iso butene being now oxidized and other products, CH 2 =C(CH 3 )CH 2 OOH, methacrolein, acetone, carbon monoxide, carbon dioxide and water being formed in appreciable yields. It is suggested that autocatalysis is due to the reaction of a small proportion of the hydroperoxides produced with HBr to give radicals, and that the main chain carriers are bromine atoms and peroxy radicals, the former either adding to the double bond of the olefin or at the higher temperatures abstracting hydrogen from a methyl group and the latter abstracting hydrogen from HBr to give the hydroperoxides, adding to the double bond of iso butene to give eventually diperoxides or at the higher temperatures decomposing.

Reactions of Hot Hydrogen Atoms in Gaseous Hydrogen Chloride and Hydrogen Bromide

1973 ◽  
Vol 51 (5) ◽  
pp. 656-666 ◽  
Author(s):  
D. K. Jardine ◽  
N. M. Ballash ◽  
D. A. Armstrong
Keyword(s):  
Carbon Dioxide ◽  
Cross Section ◽  
Hydrogen Bromide ◽  
Gaseous Hydrogen ◽  
Initial Kinetic Energy ◽  
Zero Energy ◽  
Hydrogen Atoms ◽  
Abstraction Reaction ◽  
Thermal Region ◽  
The Cross

Hydrogen atoms of initial kinetic energy E0 = 1.15 or 2.1 eV were produced photolytically and their reactions with HCl were studied at 300 °K using bromine as a scavenger. The fraction, FH, undergoing reaction 2 while hot was found to be 0.79 ± 0.02 and 0.55 ± 0.02 for E0 = 2.1 and 1.15 eV, respectively.[Formula: see text]For 2.1 eV atoms a similar result was obtained at 200 °K with chlorine as scavenger. On the addition of carbon dioxide as a moderator FH decreased in a manner consistent with the kinetic theory of hot atom reactions. Comparison of the present results with previous work on the D + DCl abstraction reaction showed that the cross section of the latter is probably 20 to 50% higher than that of H + HCl. The cross section of reaction 2 appears to increase with energy over most of the 0.1 to 1.1 eV range and possibly also above it. Its average magnitude over this energy region was estimated to be [Formula: see text].For atoms of E0 = 1.15 eV reacting in HBr FH is close to unity. The threshold of reaction 3′[Formula: see text]is near zero energy and its cross section rises rapidly, becoming [Formula: see text] in the thermal region for 300 °K.

CHBrO2 Carbon dioxide - hydrogen bromide (1/1)

2005 ◽  
pp. 1-1
Author(s):  
G. Graner ◽  
E. Hirota ◽  
T. Iijima ◽  
K. Kuchitsu ◽  
D. A. Ramsay ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Hydrogen Bromide

Photoinitiated hydrogen-atom reactions in carbon dioxide-hydrogen bromide complexes

1991 ◽  
Vol 95 (21) ◽  
pp. 8048-8053 ◽  
Author(s):  
Seung Koo Shin ◽  
Curt Wittig ◽  
William A. Goddard
Keyword(s):  
Carbon Dioxide ◽  
Hydrogen Atom ◽  
Hydrogen Bromide

Electron Cytochemical Study of Carbon Dioxide Laser Effect on Rhesus Monkey Cornea

1974 ◽  
Vol 32 ◽  
pp. 224-225
Author(s):  
K. C. Tsou ◽  
J. Morris ◽  
P. Shawaluk ◽  
B. Stuck ◽  
E. Beatrice
Keyword(s):  
Carbon Dioxide ◽  
Electron Microscope ◽  
Rhesus Monkey ◽  
Carbon Dioxide Laser ◽  
Cytochemical Study ◽  
Laser Effect

While much is known regarding the effect of lasers on the retina, little study has been done on the effect of lasers on cornea, because of the limitation of the size of the material. Using a combination of electron microscope and several newly developed cytochemical methods, the effect of laser can now be studied on eye for the purpose of correlating functional and morphological damage. The present paper illustrates such study with CO2 laser on Rhesus monkey.

The Critical Point Drying Method Applied to Scanning Electron Microscopy of L-929 Cells

1970 ◽  
Vol 28 ◽  
pp. 278-279
Author(s):  
Charles TurnbiLL ◽  
Delbert E. Philpott
Keyword(s):  
Electron Microscopy ◽  
Carbon Dioxide ◽  
Surface Tension ◽  
Critical Point ◽  
Freeze Drying ◽  
Attractive Alternative ◽  
Crystal Formation ◽  
Critical Point Drying ◽  
Time Required ◽  
Scanning Electron

The advent of the scanning electron microscope (SCEM) has renewed interest in preparing specimens by avoiding the forces of surface tension. The present method of freeze drying by Boyde and Barger (1969) and Small and Marszalek (1969) does prevent surface tension but ice crystal formation and time required for pumping out the specimen to dryness has discouraged us. We believe an attractive alternative to freeze drying is the critical point method originated by Anderson (1951; for electron microscopy. He avoided surface tension effects during drying by first exchanging the specimen water with alcohol, amy L acetate and then with carbon dioxide. He then selected a specific temperature (36.5°C) and pressure (72 Atm.) at which carbon dioxide would pass from the liquid to the gaseous phase without the effect of surface tension This combination of temperature and, pressure is known as the "critical point" of the Liquid.

A global perspective of ground level, 'ambient' carbon dioxide for assessing the response of plants to atmospheric CO2

2001 ◽  
Vol 7 (7) ◽  
pp. 789-796 ◽  
Author(s):  
L. H. Ziska ◽  
O. Ghannoum ◽  
J. T. Baker ◽  
J. Conroy ◽  
J. A. Bunce ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Ground Level ◽  
Global Perspective ◽  
Atmospheric Co2
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