Download or read book The Effect of Light on Cellulose Acetate written by Charles Calvert Winding and published by . This book was released on 1935 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effect of Light and of Heat on the Breaking Strength and Color Changes of Viscose and Cellulose Acetate Rayon Fabrics written by Miriam Hill Houston and published by . This book was released on 1939 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Studies of the Effect of Light on Cellulose and Cellulose Derivatives written by William James Mitchell and published by . This book was released on 1931 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Stabilization and Modification of Cellulose Diacetate written by Farukh Fatehovich Niyazi and published by . This book was released on 2008-10 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cellulose and its derivatives -- cellulose acetate -- are renewed polymers, that, together with the whole complex of valuable and indispensable properties, defines continuous growth of their production. Acetate fibres differ from cellulose fibres in light and thermooxidative stability, as the presence of ester groups decreases stability of molecular structure, owing to which destructive processes begin at much lower temperatures and weak energy effects. Since macromolecules of cellulose acetate are constructed on the basis of cellulose then mechanism of photodestruction of these polymers may be considered as general. The most important energetic factor, which photodestruction of cellulose and its derivatives depend on, is intensity of irradiation and wave length. Destruction of cellulose and its derivatives under atmospheric conditions, proceeding as a result of photochemical reaction, on the whole takes place under the action of ultraviolet rays with ?=200-360 nm. Since cellulose contains three types of chromophore groups -- hydroxyl, acetate and semiacetate and also aldehyde -- then it is considered that light absorption in the region of 250-300 nm is caused just by them. At the same time some authors, bringing the possibility of light absorption by acetal chromophore in question, have put forward the supposition that photochemically active centres in cellulose materials, containing carboxyl and hydroxyl groups, may be molecular complexes between these groups, connected by the system of hydrogen bounds with definite energy of interaction. Disproportion of intermolecular bonds, providing fixation of excited state in cellulose matrix takes place in such complexes at their excitation. Thus, there are many different hypotheses, often contradicting each other, about the effect of chromophore groups on light absorption by cellulose. There are many data about the nature of free-radical particles, being formed at irradiation of cellulose by ultraviolet light. Since, being formed products of phototransformation are highly mobile and easily undergo further transformations, method of electron-paramagnetic resonance (ESP) is one of the most effective for these particles identification. Critical analysis of a great number of works on EPR spectra interpretation is quite fully given in surveys. More than 20 different radicals are being formed at ultraviolet irradiation as a result of break of practically all bonds C-C; C-H; C-O. Main types of macroradicals, with indication of atom and groups of atoms after removal of which these macroradicals are formed, are presented in scheme 1. of this book.
Download or read book The Effect of Light on Cellulose Nitrate written by Lawrence Timothy Jilk and published by . This book was released on 1937 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effect of Light on Methyl Cellulose written by Donald Frank Chamberlain and published by . This book was released on 1940 with total page 424 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Light scattering and Viscosity Studies on Cellulose Acetate Solutions written by Lida Firouzi and published by . This book was released on 1970 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effect of Repeated Impact on Cellulose Acetate written by Otto Edward Hintz and published by . This book was released on 1943 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Light on Materials in Collections written by Terry T. Schaeffer and published by Getty Publications. This book was released on 2001-08-16 with total page 221 pages. Available in PDF, EPUB and Kindle. Book excerpt: The impact of light on works of art and archival materials has long been an issue of concern to conservators and other museum professionals, yet the literature on this subject has never been systematically reviewed. This volume fills that gap by providing a survey of the impact of exposure to light with an emphasis on photoflash and reprographic sources. The information provided will assist the professional audience, especially conservators and collections managers, in assessing the risk to art and archival objects of such exposures. The text surveys relevant photophysical and photochemical principles, photometric and radiometric measurement, and the spectral outputs of several light sources. Materials discussed include colorants and natural fibers; pulp, paper, and wood; natural and synthetic polymers; fluorescent whitening agents; photographic and reprographic materials; and objects containing combinations of materials. Approximations and assumptions used in the evaluation process are discussed in some detail, with examples of the different types of calculations. The Research in Conservation reference series presents the findings of research conducted by the Getty Conservation Institute and its individual and institutional research partners, as well as state-of-the-art reviews of conservation literature. Each volume covers a topic of current interest to conservators and conservation scientists.
Download or read book Ordnance Corps Pamphlet written by and published by . This book was released on 1956 with total page 358 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Journal of the Society of Dyers and Colourists written by Society of Dyers and Colourists and published by . This book was released on 1927 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt: For all interested in the use or manufacture of colours, and in calico printing, bleaching, etc.
Download or read book Confidential Documents written by United States. Army Air Forces and published by . This book was released on 1944 with total page 970 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Journal of Research of the National Bureau of Standards written by and published by . This book was released on 1930 with total page 1292 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Microplastics and Pollutants written by V. Sivasankar and published by Springer Nature. This book was released on with total page 327 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Notes on Graduate Studies and Research in Home Economics and Home Economics Education 1940 41 written by and published by . This book was released on 1941 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Experiment Station Record written by U.S. Office of Experiment Stations and published by . This book was released on 1933 with total page 928 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book ANC Bulletin written by United States. Munitions Board. Aircraft Committee. Subcommittee on Air Force-Navy-Civil Aircraft Design Criteria and published by . This book was released on 1943 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt: