Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 18 of 18 for “"Biominerals"”.
-
Diffraction and Spectroscopy of Marine Calcite Biominerals: Insights into Structure and Geochemistry
… on chemical information stored in the calcite biominerals produced by marine organisms. Organisms such as foraminifera and coccolithophores provide an unparalleled 'proxy’ archive of past marine conditions. The way in which these organisms record these proxy archives is largely unknown, and is …
-
Biochemical approaches to investigate biomineralization of magnesium calcite and aragonite
Biominerals are composites containing a very low percentage of organic matrix amidst a dense mineral phase. Despite having low organic contents, these natural materials are superior to most other synthetic composite ceramics in mechanical strength and toughness. Since biominerals are synthesized at …
-
Geomycology: fungal bioweathering, bioleaching, bioprecipitation and biotransformation of metals and minerals
… The formation of uranium- and lead-containing biominerals after growth of yeasts and filamentous fungi with organic phosphorus sources have also been demonstrated and characterized. Test fungi were capable of precipitating uranium phosphate and pyromorphite, and also produced mycogenic lead …
-
Biomolecular Controls on Calcium Carbonate Formation by Amorphous and Classical Pathways: Insights from Measurements of Nucleation Rates and Isotope Tracers
… complicated by the realization that carbonate biominerals can form by an amorphous to crystalline transformation process, which has prompted the question of how chemical signatures are recorded during mineralization. Investigations of mineralization processes such as the kinetics of nucleation …
-
Structural and morphological characterization of hydrozincite and its interaction with organic molecules
… social value. Common biogenic materials, such as biominerals, constructed with mineral phases and an organic matrix exhibit delicate structure with unusual optimal chemical-physical, morphological and mechanical properties, and have inspired ideas for the design and synthesis of biomimetic …
-
Nanoscale Effects of Strontium on Calcite Growth: A Baseline for Understanding Biomineralization in the Absence of Vital Effects
… processes and the significance of interpreting biominerals trace element signatures in the context of direction-specific interactions.
-
Bioinspired mineralization in hydrogels for sustainable materials processing
Biominerals have been widely studied due to their unique mechanical properties, afforded by their inorganic-organic composite structure and well-controlled growth in macromolecular environments. More recently, growing concerns over climate change and environmental sustainability and the emerging …
-
Applications of phytase-mediated phosphate biomineralizaton for the remediation of uranium mine tailings
… Previous research has indicated that phosphate biominerals (produced via the microbial hydrolysis of organic phosphate compounds) may be more sustainable and more efficient at immobilising contaminants than sourcing phosphate minerals from mined phosphate rock.;This PhD has investigated the …
-
Molecular and Functional Analysis of Otolith Formation in Zebrafish, Danio Rerio
… otoconia and fish otoliths are calcium-carbonate biominerals and important inner-ear organs that detect linear accelerations and perceive gravity. As a result, the absence, degradation, or dislocation of these structures causes severe imbalance in affected animals. The common vestibular defect …
-
Establishing a physical and chemical framework for Amorphous Calcium Carbonate (ACC) biomineralization
… (ACC) is now recognized as a precursor to CaCO₃ biominerals in a wide variety of natural environments. Recent studies suggest an ACC pathway may imprint a different set of dependencies from those established for classical growth processes. Previous ACC studies provided important insights, but a …
-
Design of polymeric substrates for controlled molecular crystallization
… semiconductors, as well as the formation of biominerals. In most practical circumstances, crystallization starts with heterogeneous nucleation at a foreign surface. Despite its widespread occurrence, mechanistic understanding of the role of a surface in heterogeneous nucleation is limited, …
-
Calcium carbonate biomineralization: A theoretical and experimental investigation of biomolecular controls on nucleation and growth
… of the organic assemblages associated with biominerals across a wide variety of taxa, has limited our understanding of how organisms use biomolecules to regulate skeletal formation. It is clear that a mechanistic picture of biomolecular controls on mineralization requires molecular-level …
-
Effect of ionic strength on heterogeneous nucleation of calcite during biomineralization
Biominerals often form within a matrix of biomacromolecules in high-salinity environments, yet the relationships for how macromolecules and ionic strength influence the crystallization of sparingly soluble salts (e.g., CaCO₃) are not established. Developing a physical picture of these controls is …
-
Effect of Bacterial Strain on MICP and its Application for the Erosion Control of Fine Sands
… mineralogy and crystalline properties of biominerals precipitated by three different ureolytic microorganisms were henceforth investigated. These strains were: S. pasteurii, S. aquimarina, and S. newyorkensis – a newly isolated microbe from the Daini-Atsumi Knoll in offshore Japan. From in …
-
Understanding ureolytic calcium carbonate biomineralization for crack repair in cementitious materials
… Crack healing through precipitation of biominerals was examined using mechanical tests and a non-destructive technique. Interestingly, from the mechanical test results, treating cracks with a combination of nutrient medium and CaCl2 at room temperature was found to provide the best …
-
Mechanical Design of Selected Natural Ceramic Cellular Solids
… despite their inherent brittle constituent biominerals (e.g., calcite or aragonite), exhibit remarkable mechanical properties, such as high stiffness and damage tolerance. In this thesis, by carefully selecting three biomineralized skeletal models with distinctly different cellular …
-
Biomimetic Materials for Biomedical Applications
… and mechanical properties. Moreover, biominerals are generally produced by easily traceable raw materials, in aqueous media and at room pressure and temperature, that is through cheap process and materials. Thus, it is not surprising that the idea to mimic those strategies proper of …
-
Biomineralized Composites: Material Design Strategies at Building-Block and Composite Levels
Biomineral composites, consisting of intercrystalline organics and biogenic minerals, have evolved unique structural designs to fulfill mechanical and other biological functionalities. Aside from the intricate architectures at the composite level and 3D assemblies of the biomineral building blocks, …