Tracer studies of carboxylic acids. Part V. Acetic acid in concentrated solutions of mineral acids

1966 ◽  
pp. 1211 ◽  
Author(s):  
Charmian O'Connor ◽  
T. A. Turney
Keyword(s):  
Acetic Acid ◽  
Carboxylic Acids ◽  
Concentrated Solutions ◽  
Tracer Studies ◽  
Mineral Acids

scholarly journals Computational notes on the electronic properties of carboxylic acid

2020 ◽  
Vol 9 (2) ◽  
pp. 1079-1082
Keyword(s):  
Acetic Acid ◽  
Carboxylic Acid ◽  
Electronic Properties ◽  
Carboxylic Acids ◽  
Normal Mode ◽  
Normal Modes ◽  
Carboxyl Groups ◽  
Vibrational Characteristics ◽  
Vibrational Features ◽  
Acetic Acids

The present work describing the electronic properties and vibrational characteristics of carboxylic acids. Acetic acid is chosen as model molecules then optimized at B3LYP/6-31g(d,p) level of theory. The vibrational frequencies were calculated at the same level of theory. Band assignments which were calculated as 18 normal modes were assigned as one compare the normal mode coordinates with original one. Band assignments were described indicating the directions of normal modes in terms the vibrating atoms of the acetic acids. It could be concluded that DFT could be a useful tool for elucidation both the structural and vibrational features of carboxylic acids and then further utilized for assignment of the structures contains carboxyl groups which are known as most reactive structures in chemistry, biology and environment.

scholarly journals Heterogeneous chemistry of monocarboxylic acids on α-Al<sub>2</sub>O<sub>3</sub> at ambient condition

2010 ◽  
Vol 10 (2) ◽  
pp. 3937-3974 ◽  
Author(s):  
S. R. Tong ◽  
L. Y. Wu ◽  
M. F. Ge ◽  
W. G. Wang ◽  
Z. F. Pu
Keyword(s):  
Acetic Acid ◽  
Formic Acid ◽  
Carboxylic Acids ◽  
Propionic Acid ◽  
Ambient Condition ◽  
Heterogeneous Reactions ◽  
Dust Particles ◽  
Monocarboxylic Acids ◽  
Al2o3 Particles ◽  
Α Al2o3

Abstract. A study of the atmospheric heterogeneous reactions of formic acid, acetic acid, and propionic acid on dust particles (α-Al2O3) was performed at ambient condition by using a diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) reactor. From the analysis of the spectral features, observations of carboxylates formation provide strong evidence for an efficient reactive uptake process. Comparison of the calculated and experimental vibrational frequencies of adsorbed carboxylates establishes the bridging coordinated structures on the surface. The uptake coefficients of formic acid, acetic acid, and propionic acid on α-Al2O3 particles are (2.07±0.26)×10−3, (5.00±0.69)×10−3, and (3.04±0.63)×10−3, respectively (using geometric area). Besides, the effect of various relative humid (RH) on this heterogeneous reactions was studied. The uptake coefficients of monocarboxylic acids on α-Al2O3 particles increase initially (RH<20%) and then decrease with the increased RH (RH>20%) which was due to the effect of water on carboxylic acids solvation, particles surface hydroxylation, and competition on reactive site. On the basis of the results of experimental simulation, the mechanism of heterogeneous reaction of dust with carboxylic acids at ambient condition was discussed. The loss of atmospheric monocarboxylic acids due to reactive uptake on available mineral dust particles can be competitive with homogeneous loss pathways, especially in dusty urban and desertified environments.

Acidities of OH compounds, including alcohols, phenol, carboxylic acids, and mineral acids

1990 ◽  
Vol 112 (6) ◽  
pp. 2047-2052 ◽  
Author(s):  
Robert W. Taft ◽  
I. A. Koppel ◽  
R. D. Topsom ◽  
F. Anvia
Keyword(s):  
Carboxylic Acids ◽  
Mineral Acids

Excess Gibbs energy for binary mixtures of acetonitrile with acetic acid, propionic acid, isobutyric acid, and trimethylacetic acid

1991 ◽  
Vol 69 (12) ◽  
pp. 2117-2121 ◽  
Author(s):  
T. S. Banipal ◽  
B. S. Lark ◽  
S. Singh
Keyword(s):  
Acetic Acid ◽  
Gibbs Energy ◽  
Carboxylic Acids ◽  
Propionic Acid ◽  
Binary Mixtures ◽  
Activity Coefficients ◽  
Excess Gibbs Energy ◽  
Composition Range ◽  
Isobutyric Acid ◽  
Dimerization Constant

Total vapour pressures for binary mixtures containing acetic acid, propionic acid, isobutyric acid, and trimethylacetic acid with acetonitrile have been measured for the entire composition range at 298.15 and 318.15 K using a static manometric method. All systems show positive deviations from Raoult's law, enhanced by both an increase in temperature and an increase in the methylation of acetic acid. Activity coefficients have been calculated by taking into consideration the dimerization of these carboxylic acids in the vapour phase. TSE values obtained from GE and earlier reported HE values are found to be negative for acetic acid, about zero for propionic and isobutyric acids, and positive for trimethylacetic acid for the whole composition range. The results have been interpreted in terms of various contributions such as depolymerization, heteromolecular dipole–dipole interactions, and the increasing dimerization constant and steric hindrance with increase of complexity of the acid. Key words: excess Gibbs energy, carboxylic acids, acetonitrile, activity coefficients

scholarly journals Fungicidal Activity of Fluconazole against Candida albicans in a Synthetic Vagina-Simulative Medium

2004 ◽  
Vol 48 (1) ◽  
pp. 161-167 ◽  
Author(s):  
Mahomed-Yunus S. Moosa ◽  
Jack D. Sobel ◽  
Hussain Elhalis ◽  
Wenjin Du ◽  
Robert A. Akins
Keyword(s):  
Acetic Acid ◽  
Candida Albicans ◽  
Drug Development ◽  
Carboxylic Acids ◽  
Fungicidal Activity ◽  
Vaginal Candidiasis ◽  
Ph Range ◽  
Cure Rates ◽  
Systemic Infections

ABSTRACT Fluconazole (FLZ) has emerged as a highly successful agent in the management of systemic infections of Candida. Cure rates for symptomatic candidiasis following single 150-mg FLZ dose therapy exceed 90%. In vitro, however, FLZ is fungistatic only in a narrow pH range and is not effective at vaginal pH, 4.2. This study evaluated the effect of FLZ on Candida albicans under in vitro conditions resembling the vaginal microenvironment, using vagina-simulative medium (VS). We found that FLZ was fungicidal for C. albicans in VS, but not in other media at the same pH, 4.2. In VS, FLZ was fungicidal at concentrations of ≥8 μg/ml and reduced viability by greater than 99.9%. Analysis of the components of VS indicated that 17 mM acetic acid, a concentration achieved in the vagina, was responsible for the synergistic, fungicidal effect. This effect was not seen at neutral pH. Other substrates were not effective substitutes for acetic acid; however, short-chained carboxylic acids, glyoxylate and malonate, were effective. Most strains of C. albicans that were resistant to FLZ under standard conditions were killed by FLZ plus acetate. Other species of Candida were also killed, except C. krusei and C. glabrata. This study shows that FLZ has fungicidal activity for Candida species under in vitro conditions that mimic the vaginal microenvironment. This raises the possibility that FLZ may also have fungicidal effects during treatment of vaginal candidiasis. Elucidating the mechanism by which FLZ and acetate interact may disclose vulnerable pathways that could be exploited in drug development.

Thermokinetics of Cellulose Fiber Penetration by Physically and Chemically Reactive Liquids and the Structure of Accessible Regions

1969 ◽  
Vol 39 (7) ◽  
pp. 666-677 ◽  
Author(s):  
Edward Balcerzyk ◽  
Wojciech Kozlowski ◽  
Gabriel Wlodarski
Keyword(s):  
Acetic Acid ◽  
Cellulose Fiber ◽  
Regenerated Cellulose ◽  
Hydroxyl Groups ◽  
Concentrated Solutions ◽  
Zone Structure ◽  
Native Cellulose ◽  
Heat Effects ◽  
Order Of Magnitude ◽  
Intermolecular Distances

The thermokinetics of the action of water, methanol, ethanol, n-propanol, n-butanol, acetic acid, and concentrated aqueous solutions of NaOH and ethylenediamine on native, mercerized, and regenerated cellulose has been studied by a microcalorimetric method. The penetration rate depends, first of all, on the structure of accessible regions, the dimensions of the penetrant molecule, and the penetrant reaction with hydroxyl groups. If the penetrant molecule has suitable dimensions, the penetration becomes a slow process, making it possible to follow the structural differences in the accessible region even in fibers of the same type. Such liquids are ethanol and acetic acid for native cellulose, methanol and concentrated solutions of ethylenediamine for regenerated cellulose, and concentrated solutions of NaOH (37.5% and 41.5%) for all kinds of cellulose. The accessible phase in cellulose has a discontinuous structure within the spacing of structural elements in the intermicrofibrillar and intermolecular regions. This discontinuity may sometimes be the cause of composite thermograms. Similar thermograms with two characteristic peaks are obtained for some viscose fibers which have at least a two-zone structure of the skin-core type. The intermolecular distances in the accessible regions of microfibrils seem to be of the same order of magnitude as that of the ethanol molecule with reference to native cellulose and the methanol molecule, to regenerated cellulose. The structure of these regions readily undergoes specific changes under the influence of various treatments. This is reflected in the shape of thermograms and magnitude of integral heat effects. The results indicate that the microcalorimetric measurements of the penetration thermokinetics may be a useful tool for investigating the accessible regions

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