Search Results (50)
Optimization and application of MeV time-of-flight secondary ion mass spectrometry in the standard and low primary ion beam energy mode
Time-of-flight secondary ion mass spectrometry using MeV ions (MeV ToF SIMS) has been around for a few decades as a reliable, surface-sensitive method for the detection of molecular ions having masses up to 1000 Da. It provides excellent lateral resolution of a few μm for imaging of organic samples, making …
Alkali-activated steel slag-based materials
Alkali activation is a chemical process in which aluminosilicate-rich materials that dissolve in basic media at room temperature form binding phases by polycondensation. Alkali-activated materials (AAM), also called geopolymers, are inorganic aluminosilicate-based materials produced mainly from fly ashes and metallurgical slags or clays with high Al and Si content and …
Annotation of semi-polar organic contaminants by using gas chromatography coupled to mass spectrometry and machine learning
Contaminants of emerging concern (CECs), representing a subgroup of organic compounds of natural or synthetic origin, and their degradation and transformation products (TPs), with potentially harmful effects on humans, biota, and the environment, are the eco-exposome (EE) constituents of utmost importance. Their identification, quantification, and continued investigation into their environmental …
Low-Pressure Plasma Functionalisation of Fluoropolymers
In the present thesis, the problem of the functionalisation of fluoropolymers was addressed. As chemical methods for the functionalisation of fluoropolymers apply environmentally harmful chemicals, the research was directed to low-pressure non-equilibrium radiofrequency (RF) inductively coupled plasmas of environmentally friendly gasses. The research was focused on polytetrafluoroethylene (PTFE), the most …
Synergistic action of organic inhibitors to mitigate corrosion of aluminium, copper and aluminium-copper alloy in chloride solution
The inhibitory action of organic compounds, 2-mercaptobenzimidazole (MBI), octylphosphonic acid (OPA) and their binary combinations was studied on aluminium, copper and aluminium alloy (AA) 2024 in chloride environments by ex-situ conventional electrochemical methods and surface-analytical techniques. In addition, the influence of pre-treatment of the metal surface and the choice of …
Combining neural and symbolic representations in natural language processing
The thesis addresses a novel representation learning framework, combining neural and symbolic text representations, and demonstrates its utility for tackling diverse natural language processing problems. The proposed approach, avoiding the deficiencies of purely symbolic and purely neural methods, can be applied for the generation of efficient text representations. Its usefulness …
Chirality and nanoparticles enforced stabilization of topological defects in liquid crystals
Of our main interest in this work is the stabilization of assemblies of topological defects (TDs) in liquid crystals (LCs). Due to the topological origin of TDs, the physics of defects is of interest for all branches of physics, including condensed matter systems, particle physics, and cosmology. LCs represent an …
An automated vulnerability detection for website security
Although large research efforts on web application security have been invested for more than a decade, the security of web applications is still a challenging problem. The main focus of the cybersecurity community has been to make operating systems and communication networks more secure and harder for attackers to penetrate. …
Removal of contaminants of emerging concern using algal photobioreactors
Contaminants of emerging concern (CEC) are organic pollutants occurring in wastewater and consequently enter the environment. An alternative to conventional wastewater treatment are algal photobioreactors, which treat wastewater with low energy input while producing nutrient- and energy-rich algal biomass and treated water, which both have the potential to be reused. …
Charge compensation mechanisms and twinning in doped SnO2-based ceramics
Tin (IV) oxide, SnO2 (cassiterite), is an n-type semiconductor with an advantageous combination of chemical, electric and optical properties that make it suitable for a range of applications, from solid-state gas sensors, transparent conductive coatings, oxidation catalysts and varistors. In varistor ceramics, grain growth studies are of particular interest, because …