scholarly journals MICROWAVE SPECTRUM OF ACETIC ACID: THE THIRD AND FOURTH EXCITED TORSIONAL STATES

2021 ◽  
Author(s):  
V. Ilyushin ◽  
E. Alekseev ◽  
Olga Dorovskaya ◽  
Yan Bakhmat
Author(s):  
Vadim Ilyushin ◽  
Yan Bakhmat ◽  
Eugene Alekseev ◽  
Olha Dorovskaya
Keyword(s):  

1987 ◽  
Vol 40 (7) ◽  
pp. 1147 ◽  
Author(s):  
EJ Oreilly ◽  
G Smith ◽  
CHL Kennard ◽  
TCW Mak

The crystal structures of (2-formyl-6-methoxyphenoxy)acetic acid (1), diaquabis [(2-formyl-6-methoxyphenoxy) acetato ]zinc(11) (2), tetraaquabis [(2-chlorophenoxy) acetato ]zinc(11) (3), triaquabis [(2-chlorophenoxy) acetato ]cadmium(11) dihydrate (4) and lithium (2-chloro- phenoxy )acetate 1.5 hydrate (5) have been determined by X-ray diffraction. The acid (1) forms centrosymmetric hydrogen-bonded cyclic dimers [O…0, 2.677(6) �] which are non-planar. Complex (2) is six-coordinate with two waters [Zn- Ow , 1.997(2) �] and four oxygens from two asymmetric bidentate carboxyl groups [Zn-O, 2.073, 2.381(2) �] completing a skew trapezoidal bipyramidal stereochemistry. Complex (5) is also six-coordinate but is octahedral, with two trans-related unidentate carboxyl oxygens [mean Zn-O, 2.134(9) �] and four waters [mean Zn-O, 2.081(9) �]. The seven-coordinate complex (4) has crystallographic twofold rotational symmetry relating two :symmetric bidentate acid ligands [ Cd -O, 2.26, 2 48(:) �] and two waters [ Cd -O, 2.34(2) �] while the third water lies on this axis [ Cd -O, 2.27(2) �]. In contrast to the monomers (2)-(4), complex (5) is polymeric with tetrahedral lithium coordinated to one water and three carboxylate oxygens [mean Li-0, 1.95(1) �]. The essential conformation of the free acid is retained in complexes (2), (3) and (4) but in (5), it is considerably changed.


1963 ◽  
Vol 9 (2) ◽  
pp. 121-134 ◽  
Author(s):  
Nathan Radin ◽  
Adalbert L Gramza

Abstract Three recrystallization technics were used to fractionate five commercial cholesterol products and one artificial mixture. One technic involved the recrystallization of cholesterol from absolute ethyl alcohol, the second technic involved the recrystallization of cholesterol from glacial acetic acid, and the third technic used the dibromide derivative method. The molar absorptivities for the various crystal batches were in the range of 1610 to 1750 L. mole-1 cm.-1 at 620 mµ with a modified Liebermann-Burchard procedure. The molar absorptivities were in the range of 9,800 to 11,500 L. mole-1 cm.-1 at 560 mµ with a modified sulfuric acid-iron method. The original products and the ethyl alcohol recrystallized products showed molar absorptivities at the lower limits of the ranges, while the glacial acetic acid and dibromide derivative recrystallized cholesterol showed molar absorptivities at the higher limits of the ranges. Absorption peaks at 235 mµ for methyl alcohol solutions of the cholesterol preparations were used to estimate cholesterol impurities on the basis of 7-keto cholesterol acetate absorption values. The decrease of absorption in the ultraviolet spectral region established that impurities were removed from the cholesterol preparations studied.


1973 ◽  
Vol 17 (2) ◽  
pp. 209-212 ◽  
Author(s):  
P. R. Lawrence ◽  
P. C. Thomas

SUMMARYComplete C, N and energy balances were carried out on two mature sheep receiving a basal diet of pelleted hay plus continuous intraruminal infusions of either water or 400 kcal/day of propionic acid, butyric acid or a mixture of acetic acid and sodium acetate, for periods of 1 to 5 weeks. The efficiency of utilization for maintenance plus fattening of the basal diet and the basal diet supplemented with acetate, propionate or butyrate was 20·7 ± 1·0%, 28·3 ± 1·5%, 30·2 ± 0·5% and 31·3 ± 0·2%, respectively. The calculated efficiency of utilization for fattening (kf) of the infused energy sources was 69·9 ± 8·4%, 84·0 ± 3·4% and 86·0±2·0% for acetate, propionate and butyrate, respectively. In most instances kf did not vary with the length of the period of infusion but in one sheep there was an adverse response to the infusion of the acetate mixture, and during the first week of infusion kt was only 29·3%. During the third and fifth weeks of the infusion the corresponding values were 76±3% and 72±5%.


1983 ◽  
Vol 102 (2) ◽  
pp. 273-288 ◽  
Author(s):  
B.P. van Eijck ◽  
F.B. van Duijneveldt

1993 ◽  
Vol 12 (1) ◽  
pp. 19-24 ◽  
Author(s):  
Seema Mathur ◽  
S.J.S. Flora ◽  
R. Mathur ◽  
S. Das Gupta

The efficacy of three common polyaminocarboxylic acids in the treatment of experimental beryllium intoxication was investigated in male rats. N-(2-hydroxyethyl) ethylene diamine triacetic acid (HEDTA) was more effective than calcium disodium ethylenediamine tetraacetic acid (CaNa2EDTA) in reducing the beryllium concentration of the blood, kidneys and spleen and reducing beryllium-induced inhibition of hepatic alkaline phosphatase activity. HEDTA was also most effective in reducing histopathological lesions in the liver and spleen. Compared to these two chelators, the third amino chelator, calcium trisodium diethylene triaminepenta acetic acid (CaNa3DTPA) produced severe deleterious effects in the liver and systemic toxicity. The results suggest that HEDTA is a promising chelator for beryllium toxicity while DTPA enhances the toxic manifestation of beryllium.


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