Results 301 to 310 of about 212,547 (332)

Bleaching Activators and the mechanism of bleaching activation

Journal f�r Praktische Chemie/Chemiker-Zeitung, 1992
Bleaching activators are compounds with O- or N-bounded acetyl groups which are able to react with the strongly nucleophilic hydroperoxy anion to yield peroxyacetic acid. The peroxyacetic acid is decomposed in weakly basic media in a bimolecular reaction forming singlet oxygen.
Jörg Hofmann, Gerhard Just, Wilhelm Pritzkow, H. Schmidt   +3 more
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Selection of bleaching agents for dry bleaches

Journal of the American Oil Chemists' Society, 1983
AbstractDry bleaches or all‐fabric dry bleaches are increasing in usage (7% +, annually, is quoted) because the consumer is seeking fabric and dye safety coupled with good stain removal. Additionally, the consumer wants a product which requires less sorting of fabrics or colors and aids in the cleansing and stain‐removal action without color, fabric ...
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Pulp Bleaching and Bleaching Effluents

2013
In Kraft pulping, about 90–95 % of wood lignin gets solubilized during the cooking process. The remaining 5–10 % of lignin is responsible for the brown color of the Kraft pulp and unbleached paper. The objective of bleaching is to remove the residual lignin from the pulp as selectively as possible, without degrading the pulp carbohydrate, especially ...
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Coral bleaching, bleaching-induced mortality, and the adaptive significance of the bleaching response

Marine Biology, 2008
Coral bleaching events are often associated with higher levels of coral mortality but when this occurs in the chronology of individual bleaching events is poorly documented. Knowing when mortality occurs is important for understanding molecular mechanisms and the putative adaptive significance of the response (the Adaptive Bleaching Hypothesis).
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Bleaching of cotton fabric with tetraacetylhydrazine as bleach activator for H2O2

Carbohydrate Polymers, 2018
Tetraacetylhydrazine (TH) as bleach activator for H2O2 cotton bleaching was synthesized and characterized by 1H NMR, 13C NMR and MS spectra. TH has better solubility than that of TAED. The CIE whiteness index (WI), H2O2 decomposition rate and bursting strength were employed to investigate the performance of H2O2/TH bleaching system.
Kelu Yan, Xuan Zhang, Kai Liu
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Opalescence of bleached teeth

Journal of Dentistry, 2012
To evaluate the influence of tooth bleaching on the opalescence properties of enamel.Color of 38 specimens was determined by colorimetric analysis before and after bleaching in the reflectance and transmittance modes. The results were described as CIELab color coordinates.
Luiz Narciso Baratieri, Max Schmeling, H.P. Maia   +2 more
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On the permanence of tooth bleaching

Dental Materials, 2016
Bleaching (alias whitening) is increasingly the chosen means of modifying the appearance of teeth for cosmetic reasons. Behbehani et al. (2012) acquired the largest known data set for the effects of bleaching over time (300 patients for ∼1year), but the analysis then was rather superficial and did not exploit the full depth of information available in ...
Yacoub Al-Tarakemah, Brian W. Darvell
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DENTIST-MONITORED BLEACHING: A DISCUSSION OF COMBINATION AND LASER BLEACHING

The Journal of the American Dental Association, 1997
The traditional power bleaching and matrix bleaching systems offer many advantages for patients. However, each technique also has some drawbacks. This article recommends a combination approach, which uses the best of both systems. The article also discusses the use of lasers and their possible role in bleaching teeth.
openaire   +3 more sources