Peroxycarboxylic acids are increasingly used as bleaching agents for the laundering process. These peroxy acids can be added as such to the wash liquor or may be generated in situ by reaction of a precursor component with hydrogen peroxide. Bleaching effectiveness appears to be determined by a delicate balance of chemical reactions of peroxy acid with the staining dyes and the rate of peroxy acid decomposition under the prevailing conditions. To improve our understanding of the chemistry involved we have carried out a systematic study using a range of aromatic and aliphatic mono‐ and diperoxycarboxylic acids with various carbon chain lengths and degrees of branching. We investigated peroxy acid decomposition, bleaching of stained fabric and bleaching of a water‐soluble dye, and showed that the alkyl chain length of the peroxy acids, the presence of detergent components and the pH of the medium are important factors. Combination of the kinetic data for decomposition and bleaching reactions allows the selection of structures and conditions for optimum performance.
This paper describes highlights of phased array ultrasonic testing (PAUT) nondestructive evaluation (NDE) research activities at the Federal Highway Administration’s (FHWA’s) Advanced Sensing Technology (FAST) NDE Laboratory. The work supports the goal to implement ultrasonic techniques in lieu of radiographic techniques for American Association of State Highway and Transportation Officials (AASHTO)/American Welding Society (AWS) D1.5 Bridge Welding Codeinspection of full penetration bridge fabrication welds. The paper also describes some of the advantages and disadvantages of the process to implement a PAUT inspection program. The results of this study support the goal of broader implementation of ultrasonic testing (UT) with results to date showing a good correlation of the comparative inspection results between PAUT and radiography. There is, however, a need to develop a more comprehensive set of weld flaws to ensure a fully representative flaw set is evaluated. To support that goal, the FAST NDE Laboratory is currently using ultrasonic simulation software to 03611981221090236ement the test plate data with a virtual database of simulated flaws. A successful implementation of PAUT can result in a more efficient inspection process with detailed permanent records and images of the flaw locations mimicking the historic radiograph. As more bridge fabrications incorporate PAUT, there will be a broader PAUT experience base as the AWS committee, teamed with the bridge fabricators, FAST NDE Laboratory, and other contributors continue to work toward replacing all required radiography in AWS D1.5 with an option to use PAUT.
The pipeline tracking technique offers a considerable gain in efficiency in comparison with the currently used pipeline surveying technique. The new technique enables the survey vessel to move more or less parallel to the pipeline, instead of crossing time and again at right angles. The tracking technique employes a standard subbottom profiler together with two detectors, suspended from paravanes on each side of the ship. A colour-television system provides the helmsman with readily intelligible rerlection information, which enables him to keep track of the pipeline.The tracking technique was extensively tested in cooperation with the Netherlands Ministry of Transport and Public Works on their survey vessel 'Volans'. The test included surveys in the Dutch, German and Danish sectors of the North Sea over the Pennzoil, Placid and Emden-Ekofisk pipelines, the last-mentioned of which is partly covered with rocks. A smaller diameter interfield line was also tracked succesfully.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.