Karel Klouda

Fullerene Derivatives, Preparation, Identification and Use

This article is focused on oxidation and halogenation of fullerene, identification of the prepared products and their potential application. The Fourier transform infrared (FTIR) spectrometry was used for analysis of oxidized fullerene derivative and material balance and elemental analysis were used to identify the summary composition of the prepared fullerene halogen derivatives. We has conformed yet the radioprotective ability of oxidized fullerene in our recently published work radioprotective properties and toxicity test of C60 fullerene derivative in vivo & in vitro. Since radioprotective properties are associated with the ability to recapture free radicals in the system (formed due to radiolysis of water in the physiological environment), this property is closely connected also with fire-retarder properties, when the fire is also a radical mechanism. We tested thermal properties of polyvinyl alcohol (hereinafter PVA) nanofibers prepared with C60 and its derivatives as nanocomposites. The TG-DTA and TG-DSC analysis were used for this purpose. We have demonstrated experimentally that a retarder on C60oxi basis and C60 halogenderivative has good results in increasing of thermal resistance of PVA-based nanofibers.

Biochar Modification, Thermal Stability and Toxicity of Products Modification

Abstract Biochar is a product obtained from processing of waste biomass. The main application of biochar is in soil and environment remediation. Some new applications of this carbonaceous material take advantage of its adsorption capacity use it as a heterogeneous catalyst for energy storage and conversion etc. This contribution describes thermal stability of the original biochar. It discusses biochar modified by chemical and physical methods including a new compound of biochar-graphene oxide. The purpose of the modifications is to increase its active surface to introduce active functional groups into the carbon structure of biochar in relation to fire safety and toxicity of those products.

Phytotoxicological tests - applications of foils based on graphene (graphene oxide)

Abstract This paper discusses the problematics of phytotoxicity of chemicals. It mainly focuses on the phytotoxicity of nanomaterials made of graphene. It describes phytotoxicological tests performed with foils from materials belonging to the graphene family. It also describes testing the influence of plants on these films. Furthermore, the paper discusses the issues of mutual influence between plants and tested nanomaterials.

Fine and Ultrafine Aerosol in Ostrava Ambient Air

Air quality in the Moravian-Silesian Region and especially in the Ostrava agglomeration represents a very important factor influencing the environment and health of the local population. The area has been burdend for more than two centuries with rapid development of the mining industry and related metallurgical and chemical production. As a result, hundreds of tons of pollutants have progressively been released into the atmosphere. Some of them have been gradually eliminated from the environment; others, such as some heavy metals, remain locally present and burden the local landscape. Ultrafine particles (UFPs; diameter less than 100 nm) are ubiquitous in urban air and an acknowledged risk to human health. Therefore, recurrent situations when statutory limits for airborne dust and selected chemical pollutants are exceeded require more detailed research focused on the sources, paths of propagation, chemical composition and morphology of ultrafine aerosol (UFA). In order to comply with these objectives measurements were carried out directly in production halls and the vicinity of industrial technologies with expected high UFA emission. In line with global trends, focus is increasingly placed on solid aerosols with particle sizes below 1 µm and, where appropriate, on nanoparticles. This is mainly due to a much greater penetration of these particles into an organism and a subsequent initiation of some serious diseases.

The Spread of Hazardous Substances in the Prague Metro System - Experiments Aimed at Improving Its Safe Operation

The paper points out hazards of underground structures, particularly in city agglomerations. It describes on-site experiments that focused on monitoring the spread and concentration distribution of aerosols using a toxic substance substituent in the Prague metro system. The results are analyzed with respect to the place where the substituent was released. The paper also indicates factors that affect actual the operation of toxic substances in the metro system, and it describes hazards associated with the secondary contamination of rescue service units intervening to rescue persons contaminated with toxic substances. In conclusion, it also mentions experiments dedicated to the spread of biological agents.