Hydrolysis determination

Another stratagem to avoid nonideality of the gas state is to compare heats of formation of fluorides derived from fluorine combustion on the element, with heats of hydrolysis determined directly or indirectly, as in... 

A very large number of proteins have now been hydrolysed and the products of hydrolysis determined by these methods by investigators not only in Germany, but also in France and America. The results are collected together in the following tables which are arranged according to the classification of the proteins. 

JL MacDonald, MW Krueger, JH Keller. Oxidation and hydrolysis determination of sulfur amino acids in food and feed ingredients collaborative study. J Assoc Off Anal Chem 68 826-829, 1985. 

On the other hand, water molecules in traces, as they appear on the hydrophilic silica surface, activate the surface as well as the silanes. This is due to the two-step process of the silanization. When a silane approaches the surface the groups X will react with the water to form silanol SiOH groups, a reaction called hydrolysis. The hydrolysis determines the overall reaction speed and depends on the groups X [425], It decreases in the series Cl > OMe > OEt. After hydrolysis the silanol condensates in a second step with the silanol groups from the silica surface. 

Hydrolysis of alanine p-nitroanilide according to Roncari and Zuber (67). h Extent of hydrolysis determined after overnight incubation at 37°C of substrate with tissue homogenate aliquots containing about 20 AAN units per assay. 

Miss Frush and IsbelF applied the Konigs-Knorr reaction to their crystalline pentaacetyl-a-D-(a)-guloheptosyl bromide and succeeded in isolating the tetraacetyl-D-(a)-guloheptose methyl 1,2-orthoacetate (XIII) in nearly quantitative yield. The operation was carried out by shaking a mixture of powdered Drierite (anhydrous calcium sulfate), freshly prepared silver carbonate and the crystalline bromide in methanol at 0° for forty-four hours. The reaction was studied by analysis of the final solution. The difference between the results obtained by acid (0.1 N) and by alkaline (0.1 N) hydrolysis determined the amount of orthoacetate. Within experimental error the reaction product consisted exclusively of the orthoacetate. 

In conditions of acidic hydrolysis, determination of cephem analogs took place. Vanadium(IV) after reduction from vanadium(V), reacted with forming degradation products. Colored complexes of some cephem analogs (cephalexin, cephaprine sodium, cefazolin sodium, cefotaxime) were found, absorbing at 515, 512, 518 and 523 nm, respectively (Fig. 19) [59]... 

The physical properties of PVA depend to a greater extent on the method of synthesis than do those of most other polymers. This is because the final properties are affected by the polymerization of the parent PVAc, hydrolysis conditions, drying, and grinding (1). For example, the degree of hydrolysis determines the final glass transition temperature of PVA, usually between 58 and 85 °C. 

Extrapolated to zero time hydrolysis. Determined as t steic acid. 

Hydrolysis Determination Aged solutions were analyzed by one or more of the following methods ... 

The content of humidity from PET melt is important also in connection with the hydrolysis of polyester macromolecules, because hydrolysis determines the decrease of the degree of polymerization. 

Group 1 or group 2 with group 4. SDS or NaTPB in alkaline solution (0.1 M alkali) if the imidazoline contains a ring structure. SDS in alkaline solution after acid hydrolysis (all cases). Either of these determines group 1 or 2. Extraction and determination of fatty acid after acid hydrolysis determines group 4. 

International Organization for Standardization, Surface active agents—detergents—anionic-active matter stable to acid hydrolysis—determination of trace amounts, ISO 2868 1973. Geneva, Switzerland. 

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