Thermodynamics of aqueous mixtures of electrolytes and nonelectrolytes. IV. Transfer of hydrochloric acid from water to aqueous acetic acid at 25.degree.

1968 ◽  
Vol 72 (3) ◽  
pp. 1064-1067 ◽  
Author(s):  
John H. Stern ◽  
J. M. Nobilione
Keyword(s):  
Acetic Acid ◽  
Hydrochloric Acid ◽  
Aqueous Acetic Acid ◽  
Aqueous Mixtures ◽  
Mixtures Of Electrolytes

A COMPARISON OF THE PROPERTIES OF PENTAACETATES AND METHYL 1,2-ORTHOACETATES OF GLUCOSE AND MANNOSE

1955 ◽  
Vol 33 (1) ◽  
pp. 109-119 ◽  
Author(s):  
R. U. Lemieux ◽  
Carol Brice
Keyword(s):  
Acetic Acid ◽  
Hydrochloric Acid ◽  
Zinc Chloride ◽  
Main Product ◽  
Stannic Chloride ◽  
Aqueous Acetic Acid ◽  
Silver Acetate ◽  
Silver Carbonate ◽  
Ethyl Mercaptan ◽  
Glucose Pentaacetate

The rates of exchange of acetate—concurrent with anomerization—between the C1-acetoxy groups of the pentaacetates (0.05 M) of D-glucose and D-mannose and stannic trichloride acetate (0.05 M) in chloroform containing stannic chloride (0.05 M) were determined at 40 °C. using isotopically labelled acetate. 1,2-trans-α-D-Mannose pentaacetate underwent exchange seven times more rapidly than the β-1,2-cis-anomer but eight times less rapidly than 1,2-trans-β-D-glucose pentaacetate. The latter compound was 450 times more reactive than the α-1,2-cis-anomer. In accordance with these results, the D-mannose pentaacetate underwent mercaptolysis in ethyl mercaptan containing zinc chloride at rates intermediate to those found for the D-glucose pentaacetates. The main product from the mannose pentaacetates was in each case ethyl 1,2-trans-α-D-1-thiomannopyranoside tetraacetate (60–70% yield). Tetra-O-acetyl-β-D-glucopyranosyl chloride with silver acetate gave β-D-glucose pentaacetate when the reaction was carried out in dry acetic acid but gave 2,3,4,6-tetra-O-acetyl-α-D-glucose in 90% aqueous acetic acid. Tetra-O-acetyl-β-D-glucopyranosyl chloride with methanol and silver carbonate gave a sirupy product with the properties expected for methyl 1,2-ortho-O-acetyl-α-D-glucopyranose triacetate. The substance was hydrolyzed by 0.005 N hydrochloric acid in 95% dioxane 18 times more rapidly than the corresponding derivative of β-D-mannose. The significance of these observations toward an understanding of the effect of configuration on reactivity is discussed.

Novel Compound from Flowers of Moringa oleifera Active Against Multi- Drug Resistant Gram-negative Bacilli

2020 ◽  
Vol 20 (1) ◽  
pp. 69-75
Author(s):  
Santi M. Mandal ◽  
Subhanil Chakraborty ◽  
Santanu Sahoo ◽  
Smritikona Pyne ◽  
Samaresh Ghosh ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Moringa Oleifera ◽  
Aqueous Acetic Acid ◽  
Phytochemical Analysis ◽  
Hydroxyl Groups ◽  
Drug Resistant ◽  
Gram Negative ◽  
Isolated Compound ◽  
Conventional Antibiotics

Background: The need for suitable antibacterial agents effective against Multi-drug resistant Gram-negative bacteria is acknowledged globally. The present study was designed to evaluate the possible antibacterial potential of an extracted compound from edible flowers of Moringa oleifera. Methods: Five different solvents were used for preparing dried flower extracts. The most effective extract was subjected to fractionation and further isolation of the active compound with the highest antibacterial effect was obtained using TLC, Column Chromatography and reverse phase- HPLC. Approaches were made for characterization of the isolated compound using FTIR, NMR and Mass spectrometry. Antibacterial activity was evaluated according to the CLSI guidelines. Results: One fraction of aqueous acetic acid extract of M. oleifera flower was found highly effective and more potent than conventional antibiotics of different classes against Multi-drug resistant Gram-negative bacilli (MDR-GNB) when compared. The phytochemical analysis of the isolated compound revealed the presence of hydrogen-bonded amine and hydroxyl groups attributable to unsaturated amides. Conclusion: The present study provided data indicating a potential for use of the flowers extract of M. oleifera in the fight against infections caused by lethal MDR-GNB. Recommendations: Aqueous acetic acid flower extract of M. oleifera is effective, in-vitro, against Gram-negative bacilli. This finding may open a scope in pharmaceutics for the development of new classes of antibiotics.

Highly selective separation of acetic acid and hydrochloric acid by alkylamide based on double hydrogen bond coupling mechanism

2021 ◽  
pp. 119110
Author(s):  
Yaqiang Li ◽  
Lijuan Liu ◽  
Qifeng Wei ◽  
Xiulian Ren ◽  
Maozhong An
Keyword(s):  
Hydrogen Bond ◽  
Acetic Acid ◽  
Hydrochloric Acid ◽  
Selective Separation ◽  
Coupling Mechanism ◽  
Double Hydrogen

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.

Compatibility studies of chitosan/PVA blend in 2% aqueous acetic acid solution at 30°C

2010 ◽  
Vol 82 (2) ◽  
pp. 251-255 ◽  
Author(s):  
H.M.P. Naveen Kumar ◽  
M.N. Prabhakar ◽  
C. Venkata Prasad ◽  
K. Madhusudhan Rao ◽  
T.V. Ashok Kumar Reddy ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Acid Solution ◽  
Acetic Acid Solution ◽  
Aqueous Acetic Acid ◽  
Compatibility Studies ◽  
Aqueous Acetic Acid Solution

scholarly journals Perborate Oxidation of Substituted 5-Oxoacids in Aqueous Acetic Acid Medium: A Kinetic and Mechanistic Study

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
S. Shree Devi ◽  
B. Muthukumaran ◽  
P. Krishnamoorthy
Keyword(s):  
Acetic Acid ◽  
Acid Medium ◽  
Reaction Rate ◽  
Reaction Medium ◽  
Activation Parameters ◽  
Reaction Rates ◽  
Mechanistic Study ◽  
Aqueous Acetic Acid ◽  
Sodium Perborate ◽  
Acetic Acid Medium

Kinetics and mechanism of oxidation of substituted 5-oxoacids by sodium perborate in aqueous acetic acid medium have been studied. The reaction exhibits first order both in [perborate] and [5-oxoacid] and second order in [H+]. Variation in ionic strength has no effect on the reaction rate, while the reaction rates are enhanced on lowering the dielectric constant of the reaction medium. Electron releasing substituents in the aromatic ring accelerate the reaction rate and electron withdrawing substituents retard the reaction. The order of reactivity among the studied 5-oxoacids is p-methoxy ≫ p-methyl > p-phenyl > –H > p-chloro > p-bromo > m-nitro. The oxidation is faster than H2O2 oxidation. The formation of H2BO3+ is the reactive species of perborate in the acid medium. Activation parameters have been evaluated using Arrhenius and Eyring’s plots. A mechanism consistent with the observed kinetic data has been proposed and discussed. Based on the mechanism a suitable rate law is derived.

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).

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