Kinetics Study of the Solid-State Acid Hydrolysis of Chitosan: Evolution of the Crystallinity and Macromolecular Structure

2010 ◽  
Vol 11 (5) ◽  
pp. 1376-1386 ◽  
Author(s):  
Anayancy Osorio-Madrazo ◽  
Laurent David ◽  
Stéphane Trombotto ◽  
Jean-Michel Lucas ◽  
Carlos Peniche-Covas ◽  
...  
Keyword(s):  
Solid State ◽  
Acid Hydrolysis ◽  
Macromolecular Structure ◽  
Kinetics Study ◽  
Hydrolysis Of

N-Unsubstituted 1,2,4-Triazole-3-carbaldehydes

1971 ◽  
Vol 24 (2) ◽  
pp. 393 ◽  
Author(s):  
EJ Browne
Keyword(s):  
Solid State ◽  
Acid Hydrolysis ◽  
Infrared Spectra ◽  
Mass Spectra ◽  
Essentially Normal ◽  
Hydrolysis Of

A series of N-unsubstituted 1,2,4-triazole-3-carbaldehydes has been prepared by acid hydrolysis of their methyl or ethyl acetals. Those with 5-aryl substituents have been shown to dimerize in the solid state to carbonyl-free hemiaminals. P.m.r. and infrared spectra indicate that monomeric 1,2,4-triazole-3-carbaldehydes are present in solution, the dimers being reformed on removal of the solvents. Parallels are drawn with benzimidazole-2-carbaldehyde, to which a similar structure has been assigned. With non-aromatic 5-substituents the hemiaminal becomes less stable, and 1,2,4-triazole-3-carbaldehyde, itself, exists predominantly in the carbonyl form. Mass spectra were consistent with essentially normal aldehyde structures.

Septanose carbohydrates. I. Acid-catalysed reaction of D-glucose with acetone

1975 ◽  
Vol 28 (3) ◽  
pp. 525 ◽  
Author(s):  
JD Stevens
Keyword(s):  
Solid State ◽  
Acid Hydrolysis ◽  
X Ray ◽  
Catalysed Reaction ◽  
Hydrolysis Of ◽  
Derivatives Of

Two septanose derivatives of D-glucose, 1,2:3,4-di-O-isopropylidene-α-D-glucoseptanos(e4 a) and 2,3:4,5-di-O-isopropylidene-D-glucoseptanos(e5 a), have been isolated from the mixture of products formed by treating D-glucose with acidified acetone. Acid hydrolysis of (4a) yielded 1,2-O-isopropylidene- α-D-glucoseptanose which has been converted into a mixture of (4a) and a third D-glucoseptanose derivative, 1,2:4,5-di-O-isopropylidene-α-D-glucoseptanose (8a). Methylation of (5a) yielded the two D-glucoseptanoside derivatives, methyl 2,3:4,5-di-O-isopropylidene-α-D-glucoseptanoside and methyl 2,3:4,5-di-O-isopropylidene-β-D-glucoseptanosiwde, which have been selectively hydrolysed to give methyl α (and β-)-D-glucoseptanosides. Conformations of these various septanose compounds are proposed on the basis of n.m.r. parameters and these conformations are compared with those found in the solid state by X-ray analysis.

Quantitative solid state NMR analysis of residues from acid hydrolysis of loblolly pine wood

2009 ◽  
Vol 100 (20) ◽  
pp. 4758-4765 ◽  
Author(s):  
Carsten Sievers ◽  
Teresita Marzialetti ◽  
Travis J.C. Hoskins ◽  
Mariefel B. Valenzuela Olarte ◽  
Pradeep K. Agrawal ◽  
...  
Keyword(s):  
Solid State ◽  
Acid Hydrolysis ◽  
Loblolly Pine ◽  
Solid State Nmr ◽  
Nmr Analysis ◽  
Pine Wood ◽  
Hydrolysis Of

Mechanism of Dilute Acid Hydrolysis of Cellulose Accounting for its Degradation in the Solid State

1992 ◽  
Vol 12 (3) ◽  
pp. 335-354 ◽  
Author(s):  
Jean Bouchard ◽  
Ralph P. Overend ◽  
Esteban Chornet ◽  
Marie-Rose Van Calsteren
Keyword(s):  
Solid State ◽  
Acid Hydrolysis ◽  
Dilute Acid ◽  
Dilute Acid Hydrolysis ◽  
Hydrolysis Of Cellulose ◽  
Hydrolysis Of

Reactions of ruthenium(III) ammine complexes. I. Competing acid hydrolysis and redox reactions of pentaammineruthenium(III) ions

1969 ◽  
Vol 47 (20) ◽  
pp. 3823-3830 ◽  
Author(s):  
T. Eliades ◽  
R. O. Harris ◽  
P. Reinsalu
Keyword(s):  
Solid State ◽  
Acid Hydrolysis ◽  
Redox Reactions ◽  
Ammine Complexes ◽  
Light Reduction ◽  
Solid State Decomposition ◽  
Presence And Absence ◽  
Hydrolysis Of

A study of acid hydrolysis of acidopentaammines of ruthenium(III) shows that aquation is not the only reaction taking place. For the halopentaammines, both in the presence and absence of light, reduction occurs with the formation of ruthenium(II) and free halogen. When azide, instead of halide ion, is coordinated to the metal, ruthenium(II) nitrogen complexes can be prepared. The solid state decomposition of [Ru(trien)(N3)2]+ ion to [Ru(trien)N3N2]+ is described.

DETERMINATION OF MICRO-AMOUNTS OF 5β-PREGNAN-3α-OL-20-ONE IN URINE USING INFRARED-SPECTROMETRY

1962 ◽  
Vol 41 (2) ◽  
pp. 234-246 ◽  
Author(s):  
H. J. van der Molen
Keyword(s):  
Infrared Spectrum ◽  
Quantitative Determination ◽  
Acid Hydrolysis ◽  
Chromatographic Separation ◽  
Pure Form ◽  
Infrared Spectrometry ◽  
Hydrolysis Of

ABSTRACT A procedure for the quantitative determination of 5β-pregnan-3α-ol-20-one in urine is described. After acid hydrolysis of the pregnanolone-conjugates in urine, the free steroids are extracted with toluene. Pregnanolone is isolated in a pure form as its acetate; after chromatographic separation of the free steroids on alumina, the fraction containing pregnanolone is acetylated and rechromatographed on alumina. Quantitative determination of the isolated pregnanolone-acetate is carried out with the aid of the infrared spectrum recorded by a micro KBr-wafermethod. The reliability of the method under various conditions is discussed under the headings, specificity, accuracy, precision and sensitivity. It is possible to determine 30–40 μg pregnanolone in a 24-hours urine portion with a precision of 25%.

Optimization of technological modes of cold acid hydrolysis of potato starch

2020 ◽  
Vol 26 (3) ◽  
pp. 222-233
Author(s):  
M. Alekseenko ◽  
V. Litvyak ◽  
A. Sysa ◽  
E. Hrabovska ◽  
O. Galenko
Keyword(s):  
Acid Hydrolysis ◽  
Potato Starch ◽  
Hydrolysis Of

FLOWTHROUGH ACID HYDROLYSIS OF RAPESEED STALKS

2012 ◽  
Vol 11 (12) ◽  
pp. 2313-2318
Author(s):  
Theodor Malutan ◽  
Adina Elena Panzariu
Keyword(s):  
Acid Hydrolysis ◽  
Hydrolysis Of
Sign in / Sign up

Export Citation Format

Share Document