NOPR Collection:

Spectral Behaviour and Solvent Effects of Some Amino-Anthraquinone Dyes

2016-07-20T05:33:58Z

Title: Spectral Behaviour and Solvent Effects of Some Amino-Anthraquinone Dyes Authors: Etaiw, Safaa H; Abou-Sekkina, Morsi M; El-Hefnawey, Gad B; Assar, Samy S Abstract: The electronic absorption spectra of various aminoanthraquinone dyes in ethanol comprise five bands in the UV region and one in the visible region (450-560 nm). The band in the visible region has been assigned to CT of the type p - a transitions which result from the interaction of the lone pair of the nitrogen atom with the phenyl ring attached to the carbonyl group. The CT nature of the band has been supported theoretically as well as by the effect of solvent on band position. E_T and Z-values have been found to correlate well with λ_maxof the CT band. The acid dissociation constants of dyes containing hydroxy, carboxy or sulphonic groups have also been determined. Page(s): 24-29

Studies on Azo Compounds: Part V-Spectrophotometric Studies on Some Quinoline Azo Dyes

2016-07-20T04:47:44Z

Title: Studies on Azo Compounds: Part V-Spectrophotometric Studies on Some Quinoline Azo Dyes Authors: Etaiw, S H; El-Morsi, M Abstract: The UV and visible spectra of some azo dyes containing a quinoline nucleus have been studied in different organic solvents, water and hydrochloric acid. The observed bands are assigned to different π-π* transitions and CT. Spectra-structure correlations are considered. The IR spectra of the compounds are discussed in relation to their molecular structures. Page(s): 19-23

Kinetics of Acetylation of Cellulose with Mono-, Di- and Tri-bromoacetic Acids and Thermo-analytical Studies of the Products

2016-07-20T04:43:22Z

Title: Kinetics of Acetylation of Cellulose with Mono-, Di- and Tri-bromoacetic Acids and Thermo-analytical Studies of the Products Authors: Bhatnagar, Satish; Agnish, S L; Bhatnagar, Hari L Abstract: The bromoacetylation of cellulose with mono-, di- and tri-bromoacetic acids has been studied kinetically in the temperature range 303.16-353.16 K. The energies of activation for the reactions of mono-, di- and tri-bromoacetic acids with cellulose have been found to be 18.94, 21.15 and 26.79 kJ mol^-1 respectively. The treated samples were subjected to DTA and TGA studies. The values of heats of decomposition for these samples increase from 0.36 to 1.04 kJ/g with increase in the concentration of bromine from 0.38 to 3.13 %. From the average percentage char yield of the treated samples and other temperature - dependent parameters, like the entropy and the free energy of activation for the pyrolytic degradation of the modified cellulose samples obtained by TGA, the flame-retarding abilities of mono-, di- and tri-bromoacetylated celluloses have been evaluated. Page(s): 13-18

Determination of Blend Composition of Acrylic/Wool Blends by Infrared Technique

2016-07-20T04:37:21Z

Title: Determination of Blend Composition of Acrylic/Wool Blends by Infrared Technique Authors: Soosamma, P C; Subramanian, D R; Venkataraman, A Abstract: A method for determining the blend composition of acrylic/wool blends by infrared technique is reported. Blend estimation is carried out from a calibration plot between the absorption of the 2235 cm^-1 band (C ≡ N) and the percentage composition of acrylic fibre. Page(s): 10-12