Determination of the Degree

The object of these studies has been the determination of the degree of association in thiazole and its alkyl derivatives. Various solvents have been used cyclohexane (154), carbon tetrachloride (155, 156), benzene and nitrobenzene (157). 

Determination of the degree of acidity of gases evaluated during the combustion of materials taken from cables by measuring pH and conductivity BS 6425-2/1993... 

The determination of the degree of dissociation of cotarnine ° and the good agreement with the values derived from measurements of electrical conductivity with those from the spectrophotometric methods is indirect evidence that no significant part of the undissociated cotarnine is in the amino-aldehyde form. In the conductance calculation, the undissociated part was neglected. If this included a significant amount of amino-aldehyde (i.e., a secondary base), there would be a noticeable discrepancy in the degree of dissociation obtained by the two methods. 

Characterization and understanding of the microstructure become important after hydrogenation and hydroformylation of the nitrile rubber since the amount and distribution of the residual double bonds influence the properties of modified rubber. The conventional analytical tools have been used to characterize the elastomers. Spectroscopy is the most useful technique for determination of the degree of hydrogenation in nitrile rubber. 

Determination of the degree of methylesterification of pectin was performed by the method of Maness et al. [8]. 

The main use of XRD consists of the identification and quantitative analysis of crystalline phases, accurate determination of lattice parameters and atomic arrangements, determination of the degree of crystallinity and crystalline size, orientation and strain. Specialised... 

The 1H NMR spectra have been used by dos Santos et al.30 in determination of the degree of substitution (DS) in chitosan Schiff bases. The DS was found from the ratio between integrations of signals... 

Determination of the degree of biotinylation can be done using the HABA assay (Chapter 23, Section 7). 

Electron spin resonance, nuclear magnetic resonance, and neutron diffraction methods allow a quantitative determination of the degree of covalence. The reasonance methods utilize the hyperfine interaction between the spin of the transferred electrons and the nuclear spin of the ligands (Stevens, 1953), whereas the neutron diffraction methods use the reduction of spin of the metallic ion as well as the expansion of the form factor [Hubbard and Marshall, 1965). The Mossbauer isomer shift which depends on the total electron density of the nucleus (Walker et al., 1961 Danon, 1966) can be used in the case of Fe. It will be particularly influenced by transfer to the empty 4 s orbitals, but transfer to 3 d orbitals will indirectly influence the 1 s, 2 s, and 3 s electron density at the nucleus. 

Excipients 13C, 25Mg, 23Na Determination of the degree of cross-linking for polymer systems, drug-excipient interaction studies (variable temperature), (pseudo)polymorphic characterization at the qualitative and quantitative level... 

The method yields unique mechanistic information, it permits the determination of kinetic parameters, it allows the determination of the degree of reversi-... 

Associated with this step is a determination of the degree to which measurements of the hazardous acidification and/or eutrophication effects can be directly related to ecosystem/human health. 

Since the comparison of rxy with the table values may be considered a somewhat weak test, it is perhaps more meaningful to compare the tr value with values in a t-distribution table for N-2 degrees of freedom (df), as is done for Student s I-tcst. This will give a more exact determination of the degree of statistical correlation between the two groups. 

The simplest way of establishing qualitatively the crystallinity of a polymer is by the observation of birefringence under a suitable microscope, taking care to exclude the possibility of orientation birefringence (see Sect. 2.3.3.5). Also thermotropic liquid crystalline polymers can show birefringence combined with relatively low viscosity. X-ray diffraction allows a quantitative determination of the degree of crystallinity as well as the usual crystallographic data. 

CA 58, 3263(1963) (Thermal decomposition and combustion processes of explosives) 26a) Vlad Sima, TechChem(Prague) 12(2), 66-9(1962) CA 61, 526(1964) (Determination of the degree of danger in explosives plants) 26b) A. Macek, ChemRevs 62, 50-2(1962) (Deflagration to detonation transition)... 

Crystallinity In crystallization of polymers, the polymer forms crystalline and amorphous regions [2,4,25]. The formation of crystalline regions is accompanied by an increase in new vibrational modes caused by their crystal lattice interactions [2]. The IR spectrum of a given polymer differs by various absorption bands, depending on whether it is in the amorphous or crystalline state [2]. The IR spectrum exhibits regularity bands, splitting, and frequency shifts. Other absorption bands are not affected by crystallization and remain the same in both cases. Crystalline and amorphous bands can be used in the determination of the degree of crystallinity independent bands are useful for the determination of sample thickness [2],... 

A useful quasi-quantitative technique allowing determination of the degree of association of such polymers was reported by Professor Morton(15). The viscosity of concentrated solutions of high molecular weight polymers is proportional to a power of their weight average molecular weight, M, viz.,... 

Bodek, . H. (1994). Potentiometric method for determination of the degree of acetylation of chitosan. In "Chitin World", (Z. S. Kamicki, M. M. Breziski, P. J. Bykowsky, and A. Wojtasz-Pajak, Eds), pp. 456-461. Wirtschaftsverlag NW-Verlag, Germany. 

In conclusion, evidence is provided in support of a sensitive procedure for the determination of the degree of branching in high polymers based on 10% solution viscosity. The method is more sensitive by a power of seven. The data cover the range of molecular weight 200,000-2 million and polydispersities of 1.2 to 18. The results of this work are explicable by the combination of the models of Zimm and Kilb and of Bueche. This is a fertile field for further research. 

Adler-Nissen, J. 1979. Determination of the degree of hydrolysis of food protein hydrolysates by trinitrobenzenesulfonic acid. J. Agric. Food Chem. 27 1256-1262. 

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