Production of Bioagent for Calcium-Based Biocement

Biocements and biogrouts are developing extensively as new materials alternative to cement and toxic chemical grouts. The most popular type of biocement is a mixture of urease-producing bacteria, urea and calcium salt. Thus, development of biotechnology to produce biomass of urease-active bacteria for large-scale biocementation is an important biotechnological task. Two strains of urease-producing bacteria, Yaniella sp. VS8 and Bacillus sp. VS1 that synthesized inducible and constitutive urease, respectively, were used in the present study. It was shown that low cost biomass of urease-active bacteria can be produced from the hydrolyzed excessive activated sludge of municipal wastewater treatment plant. The biomass of Yaniella sp. VS8 grown in this medium diminished the hydraulic conductivity of sand from 4.8 x 10-4 m/s to 5.10-8 m/s after several biotreatments with solution of 1.5 M urea and 0.75M CaCl2

Achirality in the low temperature structure and lattice modes of tris(acetylacetonate)iron(iii)

Tris(acetylacteonate) iron(III) is a relatively ubiquitous mononuclear inorganic coordination complex. The bidentate nature of the three acetylacteonate ligands coordinating around a single centre inevitably leads to structural isomeric forms, however whether or not this relates to chirality in the solid state has been questioned in the literature. Variable temperature neutron diffraction data down to T = 3 K, highlights the dynamic nature of the ligand environment, including the motions of the hydrogen atoms. The Fourier transform of the molecular dynamics simulation based on the experimentally determined structure was shown to closely reproduce the low temperature vibrational density of states obtained using inelastic neutron scattering

Potential of fungi for concrete repair

Concrete is the most widely used construction material in the world being cement one of its main components. Cement production accounts for 5-8% of anthropogenic CO2 emissions into the atmosphere. Most of the worlds infrastructures are produced from reinforced concrete and cracking is one of the major drawbacks for its durability. The cracks in concrete reduce their resistance capacity and allow the entry of harmful agents both for their microstructure and for the reinforcements located inside the structure. Sustainable solutions aimed at reducing costs and environmental impacts for this problem have been researched. The bioscience of precipitation mechanisms with microbiologically induced calcium carbonate (MICCP) is an alternative to traditionally used methods and a way to mitigate the environmental impact of using more cement and polymers. Most of the biocementation studies present bacteria as microorganisms responsible for the CaCO3 induction process. Fungi are potentially better for the biocementation process because they have more biomass and are filaments, which may aid in the mechanical behaviour of the formed bioconcrete. Thus, the present work proposes the development of a methodology to analyse the potential use of fungi present in concrete structures as biorepair agents.info:eu-repo/semantics/publishedVersio

Ecofriendly calcium phosphate and calcium bicarbonate biogrouts

An important direction of construction biotechnology is production and application of the biogrouts to decrease the hydraulic conductivity of soil or fractured rocks. The most popular biogrout is a mixture of calcium chloride, urea, and either ureolytic bacteria or enzyme urease. A disadvantage of this biogrout is the release of a large quantity of toxic ammonia to air, as well as harmful ammonium and hydroxide ions to water. The aim of this study was evaluation of two new biogrouts that release less of harmful by-products to environment. First biogrout was a mixture of acidified hydroxyapatite solution from the bone powder with an addition of two times less urea that is used in conventional biogrout. Final pH was 7. Second biogrout was a solution of calcium bicarbonate produced from chalk powder and carbon dioxide with an addition of urea and acidotolerant ureolytic bacteria. This biogrout released to environment four times less ammonium and ammonia than conventional biogrout. Final pH was 8. Precipitation of about 2 g of calcium carbonate per kg of the cracked stone diminished the water seepage through the specimen by three orders of magnitude. Geotechnical or environmental engineering applications of these environmentally friendly biogrouts are limited by the consumption of a large volume of the grouting solution. It is due to low concentration of dissolved calcium, about 200-400 g m(-3) , in these liquid biogrouts. So, these biogrouts could be most effective for the sealing and strengthening of the materials with low porosity such as the fractured rocks or cracked concrete

Facility layouts during the Fourth Industrial Revolution : A study that compares line with functional layout during today's market conditions and technological solutions

Dagens marknad är mycket osäker och föränderlig, vilket är en utmaning för bland annat industriföretag. För att förbli relevanta för marknaden måste företag anpassa sig. Anpassningen möjliggörs genom att företagen är flexibla i hela sin verksamhet. För ett industriföretag kan flexibilitet avse produktionsflexibilitet i produktionslayouter. Det är en mycket viktig komponent för att kunna hantera korta produktlivscykler och snabbt utvecklanya produkter. Denna kandidatuppsats undersöker vilken layout av de centrala layouterna, linan eller funktionella layouten, som är mest fördelaktig vad gäller flexibilitet och produktionskostnader givet nya lösningar från Industri 4.0. För att svara på frågan genomfördes en analys och en litteraturstudie baserade på ett studiebesök på Volvo fabriken i Köping. Analysen genomfördes genom att konstruera en lina som sedan skulle jämföras med en yteffektiviserad funktionell layout från Volvo fabriken i Köping. Resultaten av analysen visade att en lina med en rads placering har minst area men är lägre expansionsflexibel än en funktionell layout med Industri 4.0-lösningar.Today's market is very uncertain and changing, which is a challenge for, among other things, industrial companies. To remain relevant in the market, companies must adapt. Adaptation is made possible by the companies being flexible throughout their operations. For an industrial company, flexibility can refer to production flexibility in production layouts. It is a very important component to be able to manage short product life cycles and quickly develop new products. This bachelor's thesis examines which production layout of the main layouts, a product or a functional layout, is most beneficial in terms of flexibility and production costs given new solutions from Industry 4.0. To answer the question, an analysis and a literature study were carried out based on a study visit to the Volvo factory in Köping. The analysis was carried out by constructing a product layout which would then be compared with a surface-efficient functional layout from the Volvo factory in Köping. The results of the analysis showed that a product layout with single-row placement has the least footprint but is less expansion flexible than a functional layout with Industry 4.0 solutions

Facility layouts during the Fourth Industrial Revolution : A study that compares line with functional layout during today's market conditions and technological solutions

Dagens marknad är mycket osäker och föränderlig, vilket är en utmaning för bland annat industriföretag. För att förbli relevanta för marknaden måste företag anpassa sig. Anpassningen möjliggörs genom att företagen är flexibla i hela sin verksamhet. För ett industriföretag kan flexibilitet avse produktionsflexibilitet i produktionslayouter. Det är en mycket viktig komponent för att kunna hantera korta produktlivscykler och snabbt utvecklanya produkter. Denna kandidatuppsats undersöker vilken layout av de centrala layouterna, linan eller funktionella layouten, som är mest fördelaktig vad gäller flexibilitet och produktionskostnader givet nya lösningar från Industri 4.0. För att svara på frågan genomfördes en analys och en litteraturstudie baserade på ett studiebesök på Volvo fabriken i Köping. Analysen genomfördes genom att konstruera en lina som sedan skulle jämföras med en yteffektiviserad funktionell layout från Volvo fabriken i Köping. Resultaten av analysen visade att en lina med en rads placering har minst area men är lägre expansionsflexibel än en funktionell layout med Industri 4.0-lösningar.Today's market is very uncertain and changing, which is a challenge for, among other things, industrial companies. To remain relevant in the market, companies must adapt. Adaptation is made possible by the companies being flexible throughout their operations. For an industrial company, flexibility can refer to production flexibility in production layouts. It is a very important component to be able to manage short product life cycles and quickly develop new products. This bachelor's thesis examines which production layout of the main layouts, a product or a functional layout, is most beneficial in terms of flexibility and production costs given new solutions from Industry 4.0. To answer the question, an analysis and a literature study were carried out based on a study visit to the Volvo factory in Köping. The analysis was carried out by constructing a product layout which would then be compared with a surface-efficient functional layout from the Volvo factory in Köping. The results of the analysis showed that a product layout with single-row placement has the least footprint but is less expansion flexible than a functional layout with Industry 4.0 solutions