PubMed · 7203065
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
E M Krisiuk. 1980. [Radioactivity standards for construction materials].. https://pubmed.ncbi.nlm.nih.gov/7203065/
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
This research was undertaken to address environmental concerns associated with industrial solid waste and to reduce cement consumption in geotechnical engineering. It specifically investigates the feasibility of using steel slag (SS) and silica fume (SF) as partial substitutes for ordinary Portland cement (OPC) in soil stabilization. The effects of SS, SF, OPC, and initial moisture content on the unconfined compressive strength (UCS) of stabilized soil were investigated through single-factor experiments and response surface methodology (RSM). The results show that SS and SF can synergistically enhance the strength of stabilized soil, although their interaction effect was not statistically significant within the investigated ranges. Compared with soil stabilized solely with OPC, the addition of 18 % SS and 10 % SF reduced OPC consumption by 3 % without compromising strength. Microstructural and compositional analyses further revealed that SS mainly supplied calcium- and silica-bearing components, while SF provided highly reactive silica and micro-filling effects, jointly promoting hydration reactions and improving the compactness of the stabilized soil matrix. As a result, more hydration products were formed in the OPC/SS/SF-stabilized soil than in the OPC-stabilized soil, which contributed to pore filling and strength enhancement. This study provides useful guidance for the sustainable utilization of industrial solid waste and the low-carbon development of soil stabilization materials.
Materials being used or considered for use in space flights were examined for their susceptibility to fungal colonization. The materials included soft goods (clothing) and insulation and fabrication products such as Velcro attachments and elastic cord binders. Materials were exposed for at least 28 days in a high-humidity chamber colonized with over 50 species of fungi, including those species recommended for determining recalcitrance of materials to fungal biodegradation. At least nine of 25 products demonstrated extensive microscopic colonization by fungi, mostly by Acremonium obclavatum. Challenge procedures that rely on observations with the unaided eye, or 40 x magnification of growth by a restricted number of fungal species with a cellulosic substrate as a positive control, are insufficient for determining the resistance of synthetic substrates to fungal colonization.
Prediction of radon release from building materials is a general problem. Since it is impractical to follow each recoil radon path and measure the surface area of porous texture by experimental methods, a powerful computer simulation approach is conducted in this paper. The Monte Carlo simulation program TRIM, based on the momentum and energy conservation of the ion transport in matter, is modified to simulate the recoil path in a 3-D frame. A follow-up Monte Carlo program was established further to calculate the detailed recoil range distribution and the recoil probability (emanating power). The powerful Turning Bands Method (TBM) of random field is applied to simulate the 3-D porous texture based on the porosity and the correlation function of the porous texture. Based on the simulated porous texture, the fractal dimension of the surface is calculated and used to calculate the effective surface area for radon recoil. The relations between the air buffer thickness, embedding effect of recoil, and the measuring scale of the surface area for the porous texture are discussed and numerically calculated. After these calculations are performed, the relations between the emanating rate, surface area, material density, and porosity are established to calculate the radon emanation rate from porous materials. This paper provides a clear theoretical picture of the mechanism of radon release from the building materials. It has also potential application to the recoil release calculations of other radioactive elements from solid materials.