Search Results (60)
Synthesis and Characterization of Bi12SiO20 Thin Films Prepared by Sol-gel Method
The sillenites Bi12MO20 (M = Si, Ge, Ti, Pb, Mn, B1/2P1/2) have been recognised as promising bulk materials for electronic applications because their dielectric properties (5.5 GHz: ε = 37.4 - 41, τf = -19 – (-84) ppm/K, Q x f = 800 - 8100 and Tsin = 680 - …
The hydrolysis of AlN powder and its use for the synthesys of nanostructured alumina coatings
he thesis describes a study of aluminum nitride (AlN) powder hydrolysis in the temperature range between 5 °C and 90 °C. The analysis of the temperature dependence of the course of the hydrolysis and the reaction kinetics, along with a mechanistic model set up for the hydrolysis reactions, gives a …
Measuring the probability for heterogenous recombination of hydrogen and oxygen atoms on surfaces of fusion relevant materials
This thesis presents studies of probability of heterogeneous recombination of oxygen and hydrogen atoms on surfaces of different types of carbon-based materials. The probability of heterogenous recombination is described with a quantity called recombination coefficient, which is defined as the probability that an atom which impinges upon a solid surface …
Occurrence, fate and removal of pharmaceutical residues in water treatment
The presence of pharmaceutical residues in surface waters is an emerging environmental issue that provides a new challenge to treatment systems for potable water, wastewater and water reuse. Their principle pathways into the sewerage system are twofold: first, after being administered to patients they are normally excreted as various metabolites …
Text mining for discovering implicit relationships in biomedical literature
Data analysis with machine learning methods, when applied to large collections of text data, enables us to discover new knowledge. This knowledge, once put together, might describe the still unknown connections among phenomena and thus contribute to the formation of new hypotheses in different fields, medicine including. Also, connectivity and …
Supervised Descriptive Rule Induction
The goal of knowledge discovery in databases is to construct models or discover interesting patterns in data. Model construction and pattern discovery are frequently performed by rule learning, as the induced rules are easy to be interpreted by human experts. The standard classification rule learning task is to induce classification/prediction …
Modular gene dynamics and network theory at mesoscopic scale
Complex dynamical systems are often modeled as networks, with nodes representing dynamical units which interact through the network’s links. Gene regulatory networks, responsible for the production of proteins inside a cell, are an example of system that can be described as a network of interacting genes. The behavior of a …
Solution synthesis of nanoparticles in multicomponent oxide systems
The study of PbZrO3 (PZ), PbTiO3 (PT) and La2Zr2O7 (LZ) prepared by alkoxide sol-gel synthesis is described. PZ and PT sols were prepared from lead acetate, zirconium and titanium n-butoxide, in n-butanol and hydrolysed with Rw (molar ratio of water per lead acetate) between 2 and 15 in neutral medium …
Overall measurement uncertainty assessment of the k0-based neutron activation analysis
Neutron activation analysis (NAA) is an analytical method used for determination of the elemental mass fractions in different samples. It is based on the measurement of characteristic radiation, usually γ-rays, emitted from radionuclides formed through the process of neutron irradiation of the target element. The k0-NAA method is an NAA …
Stigmergy as an Approach to Metaheuristic Optimization
Developing metaheuristics to solve optimization problems is a rapidly growing field of research. This is due to the importance of optimization problems in the scientific as well as the industrial world. The methods developed in this dissertation are based on stigmergy: a method of communication in emergent systems, where the …