http://hdl.handle.net/10967/120 University of Tartu (Estonia), Institute of Chemistry, Molecular Technology Thu, 09 Apr 2026 20:34:57 GMT 2026-04-09T20:34:57Z http://hdl.handle.net/10967/265 Drug substances in water bodies and groundwater have become a significant threat to the surrounding environment. This study focuses on the ability of the nanoporous carbon materials to remove ciprofloxacin from aqueous solutions under specific experimental conditions and on the development of the mathematical model that would allow describing the molecular interactions of the adsorption process and calculating the adsorption capacity of the material. Thus, based on the adsorption measurements of the 87 carbon materials, it was found that, depending on the porosity and pore size distribution, adsorption capacity values varied between 55 and 495 mg g-1. For a more detailed analysis of the effects of different carbon textures and pores characteristics, a Quantitative nano-Structure-Property Relationship (QnSPR) was developed to describe and predict the ability of a nanoporous carbon material to remove ciprofloxacin from aqueous solutions. The adsorption capacity of potential nanoporous carbon-based adsorbents for the removal of ciprofloxacin was shown to be sufficiently accurately described by a three-parameter multi-linear QnSPR equation (R² = 0.70). This description was achieved only with parameters describing the texture of the carbon material such as specific surface area (Sdft) and pore size fractions of 1.1-1.2 nm (𝑉𝑁2[1.1−1.2]) and 3.3-3.4 nm (𝑉𝑁2[3.3−3.4]) for pores Fri, 25 Oct 2024 07:41:49 GMT http://hdl.handle.net/10967/265 2024-10-25T07:41:49Z http://hdl.handle.net/10967/214 The production of nanomaterials increases every year exponentially and therefore the probability these novel materials that they could cause adverse outcomes for human health and the environment also expands rapidly. We proposed two types of mechanisms of toxic action that are collectively applied in a nano-QSAR model, which provides governance over the toxicity of metal oxide nanoparticles to the human keratinocyte cell line (HaCaT). The combined experimental–theoretical studies allowed the development of an interpretative nano-QSAR model describing the toxicity of 18 nano-metal oxides to the HaCaT cell line, which is a common in vitro model for keratinocyte response during toxic dermal exposure. The comparison of the toxicity of metal oxide nanoparticles to bacteria Escherichia coli (prokaryotic system) and a human keratinocyte cell line (eukaryotic system), resulted in the hypothesis that different modes of toxic action occur between prokaryotic and eukaryotic systems. Thu, 23 Jan 2020 13:07:47 GMT http://hdl.handle.net/10967/214 2020-01-23T13:07:47Z http://hdl.handle.net/10967/210 The development of nanoporous carbon-based energy storage is a fast-growing area. To assist these developments, it is necessary to establish simple criteria and relationships between electric double-layer (EDL) capacitance and the nature of porous carbon used as an electrode material. Under special attention is carbide-derived carbon (CDC) due to high content of micropores and well tunable pore size distribution. In the current study, experimentally determined structure descriptors were compiled for 110 CDC materials, and the Quantitative nano-Structure-Property Relationship (QnSPR) approach was used for the statistical analysis and modelling of the EDL capacitance. Experimentally determined structure descriptors – the variable numeric porosity characteristics of CDC materials, were determined from N2 and CO2 adsorption measurements. Electrochemical characterization of CDC based electrodes was performed in 3-electrode test-cells using carbon reference electrode and 1.5 M spiro-(1,1')-bipyrrolidinium tetrafluoroborate (SBP-BF4) in acetonitrile as the electrolyte. It was shown that combining experimentally derived molecular descriptors of porosity, like specific surface area and volume-fractions of pore size distribution, calculated by density functional theory, allows accurate prediction of EDL capacitance. The QnSPR-s describing the gravimetric (R2=0.91) and the volumetric cathodic capacitance (R2=0.95) were developed for the nanoporous carbon in SBP-BF4 electrolyte. Wed, 06 Nov 2019 12:01:28 GMT http://hdl.handle.net/10967/210 2019-11-06T12:01:28Z http://hdl.handle.net/10967/205 Nanoporous carbon-based energy storage is a fast-growing research field thanks to high energy densities of carbon electrodes with nanoporous amorphous texture. To support the developments on electrical double-layer based ultra-capacitors it is necessary to improve understanding about relationships between the porous structure and energy storage behavior of carbon materials. This can be facilitated by the analysis of complex data sets and the development of corresponding descriptive and predictive models. Related to that this paper presents a in silico regression model to predict the suitability of various carbon materials for energy storage, thus being probably the first time a quantitative nano-structure-property relationship (QnSPR) approach is applied to the nanoporous carbon materials. With this study, which is based on the experimental data of 100 carbide-derived carbon materials, it has been shown that the electrical double-layer capacitance of carbon electrode in a nonaqueous electrolyte can be predicted using experimentally determined specific surface area and a volume of certain pore size fraction of carbon and a bulk density of carbon electrode. The three-parameter QnSPR model for volumetric cathodic capacitance of carbon in triethylmethylammonium tetrafluoroborate / propylene carbonate electrolyte, Cv,neg = f(SBET, Vd<1.14, Del), comprising the above-mentioned parameters and characterized by R2=0.94 and s2=8.7, confirms the important role of carbon pore size for the double layer capacitance. It was shown that carbon pores with a size below 1.1 nm have the most significance for achieving high energy densities in the nonaqueous electrochemical systems studied. Putting the results of this research into wider perspective, it has been shown that the QnSPR approach provides a useful tool for describing and predicting the variable performance-related physical properties of nanoporous carbon and nanomaterial properties in general. The models are available in the QsarDB repository. Tue, 10 Jul 2018 14:30:20 GMT http://hdl.handle.net/10967/205 2018-07-10T14:30:20Z