CATALYSIS OF THE CIS-TRANS ISOMERIZATION OF AZOBENZENE BY ACIDS AND CUPRIC SALTS

1959 ◽  
Vol 37 (11) ◽  
pp. 1903-1910 ◽  
Author(s):  
Stefania Ciccone ◽  
J. Halpern
Keyword(s):  
Acetic Acid ◽  
Hydrochloric Acid ◽  
Catalytic Effect ◽  
Catalytic Mechanism ◽  
Aqueous Ethanol ◽  
Metal Salts ◽  
Trans Isomerization ◽  
Conjugate Acid ◽  
Azo Group ◽  
Catalytic Effects

The catalytic effects of various acids and metal salts on the cis-trans isomerization of azobenzene in aqueous ethanol were examined kinetically. The effect of perchloric acid is apparently due to H+ ions and is interpreted in terms of a catalytic mechanism involving the conjugate acid of azobenzene. The much greater catalytic effect found for hydrochloric acid is attributed to an additional path involving catalysis by the undissociated acid. Acetic acid was found to be inactive. Of the metal salts examined only those of Cu++ showed pronounced activity which was attributed to co-ordination with the azo group. Kinetic evidence was obtained for a catalytic path involving Cu++ and H+ simultaneously.

THE METAL-CATALYZED AUTOXIDATION OF TETRALIN: I. INTRODUCTION. THE COBALT-CATALYZED AUTOXIDATION IN ACETIC ACID

1963 ◽  
Vol 41 (8) ◽  
pp. 2020-2033 ◽  
Author(s):  
Y. Kamiya ◽  
S. Beaton ◽  
A. Lafortune ◽  
K. U. Ingold
Keyword(s):  
Acetic Acid ◽  
Catalytic Effect ◽  
Catalyst Concentration ◽  
Cobalt Acetate ◽  
Metal Salts ◽  
Organic Substances ◽  
Transition Metal Salts ◽  
Theoretical Predictions ◽  
Metal Catalyzed ◽  
State Concentration

The catalytic effect of transition metal salts on the rate of autoxidation of organic substances reaches a constant value at some critical catalyst concentration. Three possible explanations of this phenomena are critically examined. The cobalt acetate catalyzed autoxidation of tetralin in acetic acid has been reinvestigated and the limiting rate of oxidation at high cobalt concentrations has been shown to be due to the production of a steady-state concentration of hydroperoxide. The present results are in fair agreement with the experimental work of Woodward and Mesrobian (J. Am. Chem. Soc. 75, 6189 (1953)) and are in excellent agreement with theoretical predictions.

Interlaboratory comparison of results of erythrocyte protoporphyrin analysis.

1978 ◽  
Vol 24 (12) ◽  
pp. 2135-2138 ◽  
Author(s):  
K W Jackson
Keyword(s):  
Acetic Acid ◽  
Hydrochloric Acid ◽  
Ethyl Acetate ◽  
Disease Control ◽  
Whole Blood ◽  
Interlaboratory Comparison ◽  
Direct Reading ◽  
Blood Samples ◽  
Erythrocyte Protoporphyrin ◽  
Whole Blood Samples

Abstract Each of 65 laboratories analyzed 10 whole-blood samples for erythrocyte protoporphyrin by one or more of several analytical procedures. These procedures were of two types: (a) extraction of protoporphyrin from the erythrocytes into ethyl acetate/acetic acid, re-extraction into hydrochloric acid, and fluorometric measurement; or (b) direct reading in a portable fluorometer (hematofluorometer), with no pretreatment of the blood sample. Interlaboratory correlation was generally poor, especially between laboratories using extraction procedures. Hematofluorometric results intercorrelated better, but they had a low bias as compared to the extraction approach. Nationwide standardization of the test is required to assure satisfactory interlaboratory performance and to identify laboratories whose results are sufficiently accurate to be used for interpretations according to guidelines set forth by the Center for Disease Control for erythrocyte protoporphyrin testing.

Effect of the ionizing radiation on the catalytic activity of the BASF K-3-10 catalyst in the low-temperature conversion of carbon monoxide by water vapour. Stability of the radiation catalytic effects

1986 ◽  
Vol 51 (8) ◽  
pp. 1571-1578 ◽  
Author(s):  
Alois Motl
Keyword(s):  
Carbon Monoxide ◽  
Catalytic Activity ◽  
Low Temperature ◽  
Catalytic Effect ◽  
Catalytic Properties ◽  
Beta Radiation ◽  
Fast Neutrons ◽  
Time Interval ◽  
The Stability ◽  
Catalytic Effects

The radiation catalytic properties of the BASF K-3-10 catalyst were studied, namely the dependence of these effects on the time interval between the catalyst irradiation and the reaction itself and also on the length of the catalyst use. The catalytic effects decrease exponentially with the interval between the irradiation and the reaction if the catalyst is kept in the presence of air. The stability of effects induced by various types of radiations increases in the sequence beta radiation - gamma radiation - fast neutrons. The radiation catalytic effect stability in the reaction increases in the same sequence.

Effect of pH, Acidulant, Time, and Temperature on the Growth and Survival of Listeria monocytogenes

1989 ◽  
Vol 52 (8) ◽  
pp. 571-573 ◽  
Author(s):  
KENT M. SORRELLS ◽  
DAVIN C. ENIGL ◽  
JOHN R. HATFIELD
Keyword(s):  
Antimicrobial Activity ◽  
Acetic Acid ◽  
Lactic Acid ◽  
Listeria Monocytogenes ◽  
Citric Acid ◽  
Hydrochloric Acid ◽  
Malic Acid ◽  
Incubation Temperature ◽  
Growth And Survival ◽  
Ph Values

The effect of different acids, pH, incubation time, and incubation temperature on the growth and survival of four strains of Listeria monocytogenes in tryptic soy broth was compared. Hydrochloric acid (HCl), acetic acid (AA), lactic acid (LA), malic acid (MA), and citric acid (CA) were used to acidify tryptic soy broth to pH values 4.4, 4.6, 4.8, 5.0, and 5.2 pH. Incubation times were 1, 3, 7, 14, and 28 d at 10, 25, and 35°C. The inhibition of L. monocytogenes in the presence of high acidity appears to be a function of acid and incubation temperature. Based on equal pH values, the antimicrobial activity is AA > LA > CA ≥ MA > HCl at all incubation times and temperatures. When based on equal molar concentration, the activity appeared to be CA ≥ MA > LA ≥ AA > HCl at 35 and 25°C, and MA > CA > AA ≥ LA > HCl at 10°C. Greatest antimicrobial activity occurred at 35°C. Greatest survival occurred at 10°C and greatest growth occurred at 25°C. Final pH of the medium was as low as 3.8 in HCl at 28 d. All strains grew well at pH values lower than the minimum previously reported (5.5–5.6).

GROWTH OF STAPHYLOCOCCUS AUREUS IN ACIDIFIED PASTEURIZED MILK1

1970 ◽  
Vol 33 (11) ◽  
pp. 516-520 ◽  
Author(s):  
T. E. Minor ◽  
E. H. Marth
Keyword(s):  
Staphylococcus Aureus ◽  
Acetic Acid ◽  
Lactic Acid ◽  
Hydrochloric Acid ◽  
Ph Value ◽  
The Other ◽  
Antagonistic Effects ◽  
Pasteurized Milk ◽  
Ph Values ◽  
Effect On Growth

The effect of gradually reducing the pH of pasteurized milk with acetic, citric, hydrochloric, lactic, and phosphoric acids over periods of 4, 8, and 12 hr on growth of Staphylococcus aureus 100 in this substrate was determined. In addition, 1: 1 mixtures of lactic acid and each of the other acids, and of acetic and citric acids were evaluated for their effect on growth of this organism. To achieve a 90% reduction in growth over a 12 hr period, a final pH value of 5.2 was required for acetic, 4.9 for lactic, 4.7 for phosphoric and citric, and 4.6 for hydrochloric acid. A 99% reduction during a 12 hr period was obtained with a final pH value of 5.0 for acetic, 4.6 for lactic, 4.5 for citric, 4.1 for phosphoric, and 4.0 for hydrochloric acid. A pH value of 3.3 was required for a 99.9% reduction with hydrochloric acid, whereas the same effect was produced at a pH value of 4.9 with acetic acid. Correspondingly lower pH values were required to inhibit growth within 8 and 4 hr periods. Mixtures of acids adjusted to pH values at the borderline for growth (12 hr period) exhibited neither synergistic nor antagonistic effects between two acids.

A Synthesis of Alkylpyridines

1960 ◽  
Vol 13 (4) ◽  
pp. 469 ◽  
Author(s):  
GWK Cavill ◽  
DL Ford ◽  
DH Solomon
Keyword(s):  
Acetic Acid ◽  
Hydrochloric Acid

The action of hydrochloric acid on a pentane-1,5-dialdehyde bis-2,4-dinitrophenylhydrazone, in acetic acid, yields the corresponding pyridine. The method is a useful one, applicable to the synthesis of various alkylpyridines. Its application to the synthesis of 2,3-dihydropyridines is also reported.

Two new energetic coordination compounds based on tetrazole-1-acetic acid: syntheses, crystal structures and their synergistic catalytic effect for the thermal decomposition of ammonium perchlorate

RSC Advances ◽  
2016 ◽  
Vol 6 (40) ◽  
pp. 33332-33338 ◽  
Author(s):  
Li Kang ◽  
Zhixian Wei ◽  
Jiangfeng Song ◽  
Yuanyuan Qu ◽  
Yale Wang
Keyword(s):  
Thermal Decomposition ◽  
Acetic Acid ◽  
Crystal Structures ◽  
Ammonium Perchlorate ◽  
Coordination Compounds ◽  
Catalytic Effect ◽  
Dsc Curves

The DSC curves of the AP thermal decomposition in the absence and presence of compounds 1, 2 or their mixtures.

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