This work describes studies on the preliminary processing of calcium aluminate mortars based on several industrial wastes and natural sub-products. The starting materials are sludges (generated in Al-anodising and surface coating industrial processes, potable water filtration/cleaning operations and cutting process of natural marble rocks), and foundry sands. These materials are all classified as non-hazardous but high daily-produced amounts involve high transportation costs for disposal. Reusing alternatives should be sought.The characterization of the waste materials is reported, including physical and chemical parameters and thermal behaviour. Several powder mixtures were prepared and fired at different temperatures. Compositional changes were assessed by XRD and powder density, average particle size, and specific surface area, were determined. The compression and flexural strengths of the corresponding pressed and sintered samples are also given.
Three surveys on the occurrence of foxing stains were carried out on papers dating from 1560 to 1975 in three Portuguese collections. Foxed papers were found to be more intensely and intrusively stained in certain time periods of each collection. Based on historical data and on the professional paper conservation experience, the authors linked the increased occurrence of foxing stains in certain time periods to the new papermaking processes and materials, which began to be introduced in the late 18th century, and in particular to a synergistic effect between three factors: the use of deficient gelatine sizing which began to present a poorer quality and homogeneity, the presence of iron-containing impurities throughout the paper leaf and a distinct sorbency of moisture. Observing batches of morphologically similar papers by using photographic imaging with different types of light sources and incidences, the authors verified that similar papers present similar foxing stains.
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.
hi@scite.ai
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.