Applications of Ultraviolet Spectrography a Study of the Transformations of Tetramethylthiuram Disulfide When It Functions as a Direct Vulcanizing Agent

1944 ◽  
Vol 17 (4) ◽  
pp. 941-942 ◽  
Author(s):  
Charles Dufraisse ◽  
André Jarrijon
Keyword(s):  
Absorption Spectrum ◽  
Absorption Spectra ◽  
Ultraviolet Absorption ◽  
Special Technique ◽  
Ultraviolet Region ◽  
Tetramethylthiuram Disulfide ◽  
Important Method ◽  
Characteristic Absorption ◽  
Definite Form ◽  
Inorganic And Organic

Abstract In addition to sulfur, which is the most common vulcanizing agent, rubber mixtures usually contain various kinds of accessory ingredients, both inorganic and organic. Among the organic ingredients, some, notably accelerators and antioxidants, are present in relatively small proportions, and these are susceptible to transformation during vulcanization. However, only in rare cases has it been possible to isolate in definite form the products of these transformations, and consequently it is difficult to interpret the part played by these substances during vulcanization. Since, with few exceptions, each accelerator and each antioxidant has its own characteristic absorption spectrum in the ultraviolet region, spectrography constitutes in general an important method for following the behavior of accelerators and antioxidants. This method has been demonstrated by Dufraisse and Houpillart, who have developed a special technique for obtaining ultraviolet absorption spectra and examining them, frequently with interesting conclusions to be drawn from such analyses.

ULTRAVIOLET ABSORPTION SPECTRA AND ACIDITIES OF ISOMERIC THIATRIAZOLE AND TETRAZOLE DERIVATIVES

1959 ◽  
Vol 37 (3) ◽  
pp. 563-574 ◽  
Author(s):  
Eugene Lieber ◽  
J. Ramachandran ◽  
C. N. R. Rao ◽  
C. N. Pillai
Keyword(s):  
Absorption Spectra ◽  
Absorption Maximum ◽  
Dipole Moments ◽  
Ring System ◽  
Ultraviolet Absorption ◽  
Characteristic Absorption ◽  
Tetrazole Derivatives

The ultraviolet absorption spectra of 5-(substituted)amino-1,2,3,4-thiatriazoles and the corresponding isomeric 1-substituted-tetrazoline-5-thiones have been studied. The spectra and the dipole moments of the 5-(substituted)amino-1,2,3,4-thiatriazoles eliminate the possibility of meso-ionic structures for these compounds. The dipole moments of 5-amino-, 5-methylamino-, and 5-dimethylamino-1,2,3,4-thiatriazole were all high but approximately of the same value (5.77 to 5.84 D). This suggests that the amino thiatriazoles are best represented by conventional covalent structures with significant ionic resonance contributions. The thiatriazole ring system exhibits a characteristic absorption maximum at 250–255 mμ and an electron-withdrawing effect approximately equal to the tetrazolyl ring system. The tetrazolinethionolyl ring system is similarly electron-withdrawing. The relative acidities of the 1-substituted-tetrazoline-5-thiones and the 5-alkylmercaptotetrazoles have also been studied and the results support the observations made on the basis of their ultraviolet absorption spectra.

scholarly journals The Near-ultraviolet Absorption Spectrum of Diimide Vapor

1974 ◽  
Vol 52 (6) ◽  
pp. 1006-1012 ◽  
Author(s):  
R. A. Back ◽  
C. Willis ◽  
D. A. Ramsay
Keyword(s):  
Absorption Spectrum ◽  
Bond Length ◽  
Gas Phase ◽  
Absorption Spectra ◽  
Ground State ◽  
Ultraviolet Absorption ◽  
Ultraviolet Absorption Spectrum ◽  
Near Ultraviolet ◽  
Bending Mode ◽  
Franck Condon

Absorption spectra of N2H2 and N2D2 in the gas phase have been obtained in the region 3000–4300 Å, consisting of about 30 diffuse bands for each compound. Long progressions in the spectra are attributed to excitation of the H—N=N bending mode, v2′, in the upper state, with much shorter progressions arising from the N=N stretching mode, v3′; values of v2′ = 1215 and 910 cm−1 and v3′ = 1550 and 1440 cm−1 were estimated for N2H2 and N2D2 respectively.The spectra are attributed to the 1Bg ← 1Ag(π* ← n+) transition of trans diimide, probably made allowed by vibronic interaction. From Franck–Condon calculations the H—N=N angle in the upper state was estimated to be 132 ± 2°, an increase of 25° from the ground-state value; the increase in the N=N bond length was estimated to be about 0.05 Å.

THE ULTRAVIOLET ABSORPTION SPECTRA OF NITROGUANIDINE DERIVATIVES

1953 ◽  
Vol 31 (1) ◽  
pp. 42-47 ◽  
Author(s):  
A. F. McKay ◽  
C. Sandorfy
Keyword(s):  
Absorption Spectrum ◽  
Absorption Spectra ◽  
Linear Structure ◽  
Addition Product ◽  
Ultraviolet Absorption ◽  
Ethanol Addition ◽  
Nitroguanidine Derivatives ◽  
Amine Addition

The ultraviolet absorption spectra of the ammonia and amine addition products of 1-nitro-2-nitramino-2-imidazoline verify the linear structure A for these compounds. Also the ethanol addition product is considered on the basis of [Formula: see text]its absorption spectrum to be N-β-nitraminoethyl-N-nitro-o-ethylisourea. The relative effects of the nitramino and nitroguanidine chromophores on the absorption spectra of several nitroguanidine derivatives are discussed.

THE ULTRAVIOLET ABSORPTION SPECTRA OF ALIPHATIC NITRAMINES, NITROSAMINES, AND NITRATES

1949 ◽  
Vol 27b (11) ◽  
pp. 828-860 ◽  
Author(s):  
R. Norman Jones ◽  
G. Denis Thorn
Keyword(s):  
Absorption Spectrum ◽  
Absorption Spectra ◽  
Ultraviolet Spectrum ◽  
Ultraviolet Absorption ◽  
Absorption Bands ◽  
Structure Formula ◽  
New Compounds

The ultraviolet absorption bands associated with the following groups have been investigated in a variety of compounds of known structure:[Formula: see text]The groups may be characterized by the ultraviolet spectrum, and the number of each type of group present in a given compound may be estimated from an analysis of the shape and intensity of the absorption spectrum. These correlations have been applied to the elucidation of the structure of new compounds isolated in the course of the investigation of the chemistry of 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX).

scholarly journals Absorption of lithium vapour

1924 ◽  
Vol 106 (735) ◽  
pp. 51-54 ◽  
Keyword(s):  
Absorption Spectrum ◽  
Absorption Spectra ◽  
Alkali Metals ◽  
Wave Length ◽  
Visible Region ◽  
Principal Series ◽  
Short Wave ◽  
Ultraviolet Region ◽  
Large Radius ◽  
Short Wave Length

The fluorescence and channelled absorption spectra of the vapours of the alkali metals have been studied by several physicists, notable among them being Roscoe and Schuster, Liveing and Dewar, Wood and his collaborators, Bevan, and Dunoyer, Wood, working with a concave grating of large radius showed that there are as many as 8,000 absorption lines in the visible region of the absorption spectrum of sodium. In a recent paper Prof. McLennan and Ainslie have given an account of some interesting experiments on the subject, where cesium has been shown for the first time to possess a channelled absorption spectrum in the neighbourhood, and on the short wave-length side, of the first member of the principal series, and a fluorescence spectrum in the near infra-red region. Though attempts were made by these authors to get spectrograms of fluorescence and channelled absorption with the vapour of lithium, no definite results could be obtained, but they pointed out that their preliminary results indicated that lithium possessed a banded absorption spectrum in the ultraviolet region between 0.4 μ and 0.3 μ The failure to obtain channelled absorption spectrum with lithium vapour was probably due to their not obtaining vapour of sufficient density, as the boiling point of the metal is of the order of 1,400°C. In this investigation there were found with lithium vapour not only channelled absorption spectra, both on the short and the long wave-length side of the first line of the principal series, but also, as in the case of sodium, it has been found that there is a fine line absorption spectrum immediately on each side of the main line.

scholarly journals THE STRUCTURE OF THE ULTRAVIOLET ABSORPTION SPECTRA OF CERTAIN PROTEINS AND AMINO ACIDS

1936 ◽  
Vol 19 (5) ◽  
pp. 739-752 ◽  
Author(s):  
Calvin B. Coulter ◽  
Florence M. Stone ◽  
Elvin A. Kabat
Keyword(s):  
Amino Acids ◽  
Absorption Spectrum ◽  
Absorption Spectra ◽  
Relative Intensity ◽  
Ultraviolet Absorption ◽  
Absorption Curve ◽  
Type I ◽  
Narrow Bands ◽  
Pneumococcus Type

1. The absorption spectra of a number of proteins in the region 2500 to 3000 A. have been found to comprise from six to nine narrow bands. In consequence of variation in the relative intensity of these bands from protein to protein, the absorption curve has a characteristic configuration for each protein. 2. These bands correspond closely in position with the narrow bands which appear in the absorption spectra of tryptophan, tyrosin, and phenylalanine. Tryptophan and tyrosin each present three bands, phenylalanine shows nine. 3. The bands in the proteins are accordingly attributed to these amino acids. In the proteins the bands are displaced from the positions which they occupy in the uncombined amino acids, in most instances, by 10 to 35 A. toward longer wavelengths. 4. The absorption spectrum of Pneumococcus Type I antibody resembles that of normal pseudoglobulin but shows characteristic differences.

Near Ultraviolet Absorption Spectra of cis and trans Acrolein and Acrolein-d1

1973 ◽  
Vol 51 (11) ◽  
pp. 1170-1175 ◽  
Author(s):  
G. A. Osborne ◽  
D. A. Ramsay
Keyword(s):  
Absorption Spectrum ◽  
Absorption Spectra ◽  
Vibrational Structure ◽  
Ultraviolet Absorption ◽  
Additional Information ◽  
Near Ultraviolet ◽  
New Information ◽  
Path Lengths ◽  
Cis And Trans

The absorption spectrum of acrolein-d1 (CH2=CH∙CDO) has been studied in the region 3900 to 4400 Å with path lengths and pressures up to 10 m atm and temperatures from 25 to 160 °C. This study provides additional information for the interpretation of the vibrational structure observed in the 3A″–1A′ (trans), 1A″–1A′ (cis), and 3A″–1A′ (cis) systems of acrolein, in addition to new information for acrolein-d1. Most of the features in these spectra are now assigned.

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