Publications by authors named "Rafal Wrobel"

Indonesia is listed as a region with high marine biodiversity, especially when considering the three large tropical ecosystems: seagrass beds, mangroves and coral reefs. It is likely that the biodiversity of diatoms in this area is also high. Samples for this research were taken from the remote area of Bawean Island and Tomini Gulf in Central Sulawesi.

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TiO was loaded on the porous nickel foam from the suspended ethanol solution and used for the photocatalytic removal of NO. Such prepared material was heat-treated at various temperatures (400-600 °C) to increase the adhesion of TiO with the support. Obtained TiO/nickel foam samples were characterized by XRD, UV-Vis/DR, FTIR, XPS, AFM, SEM, and nitrogen adsorption at 77 K.

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This work describes the effect of nitrogen and oxygen functional groups on the sorption properties of activated carbons produced from furfuryl alcohol. The poly(furfuryl) alcohol underwent carbonization in nitrogen, ammonia, and ammonia and air (in a 3:2 proportion) atmospheres at 600 °C for 4 h. The resulting materials were subsequently activated in a carbon dioxide atmosphere for 1 h at temperatures of 700 °C, 800 °C, 900 °C, and 1000 °C.

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Acetaldehyde decomposition was performed under heating at a temperature range of 25-125 °C and UV irradiation on TiO doped by metallic Ni powder and TiO supported on nickel foam. The process was carried out in a high-temperature reaction chamber, "The Praying Mantis", with simultaneous in situ FTIR measurements and UV irradiation. Ni powder was added to TiO in the quantity of 0.

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A crucial factor of a nitriding process of treated parts is surface roughness. Eight samples of 42CrMo4 steel were used to investigate the parameter represented by Ra. In the study, the innovative combined microhardness profiles were used to present results within the compound zone and diffusion layer.

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Activated carbons were prepared from avocado stone through NaOH activation and subsequent carbonization. The following textural parameters were achieved: specific surface area: 817-1172 m/g, total pore volume: 0.538-0.

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The influence of NHNO and NHClO on the porous texture and structure development of activated carbons produced from a non-porous polymeric precursor synthesized from furfuryl alcohol has been studied. The non-doped counterparts were prepared and studied for comparison purposes. NHNO and NHClO-doped polymers were carbonized under N atmosphere at 600 °C, followed by CO activation at 1000 °C and the obtained carbon materials and activated carbons were thoroughly characterized.

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Dental caries is listed by the WHO as one of the major non-communicable diseases that need to be prevented and treated. The aim of the study was to evaluate the prevalence and severity of caries expressed as the Decayed, Missing and Filled Permanent Teeth (DMFT) index in 12-year-old Polish children and to verify bacterial species related to the occurrence of dental caries. Quantitative real-time PCR analysis of DNA isolated from saliva samples was performed to detect 8 cariogenic and periopathogenic bacterial strains.

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Cost-effective activated carbons for CO adsorption were developed from molasses using HSO, HPO, HCl, NaOH, and KOH as activating agents. At the temperature of 0 °C and a pressure of 1 bar, CO adsorption equal to 5.18 mmol/g was achieved over activated carbon obtained by KOH activation.

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The aim of this report was to determine the impact of flaxseed, soy and red clover, and their bioactive substances on the lipid profile in postmenopausal women in cardiovascular diseases prevention. We used the following databases: MEDLINE (PubMed), EMBASE and the Cochrane Library. Meta-analysis indicates that the intake of flaxseed by postmenopausal women is associated with a statistically significant reduction in total cholesterol (TC) levels (weighted-mean difference (WMD) = -0.

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Adsorption and chromatographic properties of oxidized and hydrogenated 'high pressure and high temperature' synthesised diamond (HPHT) are studied using high-performance liquid chromatography. The retention factors of organic cation (benzyltributylammonium chloride), weak base (aniline), weak acid (benzoic acid), strong acid (benzenesulfonic acid), hydrophobic toluene, and hydrophilic uracil are obtained at varied pH, organic solvent content, and ionic strength of mobile phase. Both adsorbents exhibited moderate polarity with a mixed-mode retention mechanism with a combination of electrostatic, hydrophobic and hydrophilic interactions.

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The aim of the research was to determine how the admixture of nanosilica affects the structure and mechanical performance of cement concrete exposed to high temperatures (200, 400, 600, and 800 °C). The structural tests were carried out on the cement paste and concrete using the methods of thermogravimetric analysis, mercury porosimetry, and scanning electron microscopy. The results show that despite the growth of the cement matrix's total porosity with an increasing amount of nanosilica, the resistance to high temperature improves.

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DT0-activated carbons modified with HCl and HNO acids, which were used for the first time in the catalytic process of alpha-pinene isomerization, are presented in this study. The carbon materials DT0, DT0_HCl, DT0_HNO, and DT0_HCl_HNO were examined with the following methods: XRF, SEM, EDX, XPS, FT-IR, XRD, and N adsorption at -196 °C. It was shown that DT0_HCl_HNO-activated carbon was the most active material in the alpha-pinene isomerization process.

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The work presents the synthesis of FeCl-modified carbonaceous catalysts obtained from waste orange peel and their application in the oxidation of alpha-pinene in solvent-free reaction conditions. The use of waste orange peel as presented here (not described in the literature) is an effective and cheap way of managing this valuable and renewable biomass. FeCl-modified carbonaceous materials were obtained by a two-stage method: in the first stage, activated carbon was obtained, and in the second stage, it was modified by FeCl in the presence of HPO (three different molar ratios of these two compounds were used in the studies).

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The aim of this study was to prepare activated carbon materials with different porous structures. For this purpose, the biomass precursor, beech wood, was carbonized in an inert atmosphere, and the obtained charcoal was physically activated using carbon dioxide at 1273 K. Different porous structures were obtained by controlling the time of the activation process.

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Zeolite 13X (NaX) was modified through ion-exchange with alkali and alkaline earth metal cations. The degree of ion exchange was thoroughly characterized with ICP, EDS and XRF methods. The new method of EDS data evaluation for zeolites was presented.

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This work presents studies on the preparation of porous carbon materials from waste biomass in the form of orange peels, coffee grounds, and sunflower seed husks. The preparation of activated carbons from these three waste materials involved activation with KOH followed by carbonization at 800 °C in an N atmosphere. This way of obtaining the activated carbons is very simple and requires the application of only two reactants.

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One-hundred-nanometer films consisting of silver, copper, and gold nanocrystallites were prepared, and their antibacterial properties were quantitatively measured. The magnetron-sputtering method was used for the preparation of the metallic films over the glass plate. Single- and double-layer films were manufactured.

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We sequenced the plastid genomes of three diatoms from the genus , including two strains formerly designated as . At 208,097 and 216,580 bp, the plastid genomes of the latter strains are the largest ever sequenced among diatoms and their increased size is explained by the massive expansion of the inverted repeat region. Important rearrangements of gene order were identified among the two populations of cf.

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This paper describes the microstructure and properties of titanium-based composites obtained as a result of a reactive spark plasma sintering of a mixture of titanium and nanostructured (Ti,Mo)C-type carbide in a carbon shell. Composites with different ceramic addition mass percentage (10 and 20 wt %) were produced. Effect of content of elemental carbon covering nc-(Ti,Mo)C reinforcing phase particles on the microstructure, mechanical, tribological, and corrosion properties of the titanium-based composites was investigated.

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Background: The Aegean Sea coast of Turkey hosts one of the most important nesting grounds for loggerhead sea turtles () in the Mediterranean Sea. Previous studies have revealed that the sea turtle carapace provides favourable conditions for various epibiontic organisms. Epibionts occurring on the carapace have been examined from different locations in the oceans.

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Series of AgNPs/TiO-loaded carbon fiber cloth (CFC) composites were prepared by incorporation of pristine TiO and three AgNPs-modified TiO additives onto the surface of four commercial CFCs. AgNPs/TiO photocatalysts were synthesized by the wet impregnation method, including NaBH reduction of silver ions. The silver content in the modified photocatalyst was assessed by inductively coupled plasma optical emission spectrometry (ICP-OES) as well as XRD analysis.

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In this paper, the antibacterial activity of titanium dioxide modified with reduced graphene oxide (rGO) was presented. TiO/rGO photocatalysts were prepared by the hydrothermal method under elevated pressure at 180°C and heated at 100°C in Ar flow. The obtained photocatalysts were characterized by means of XRD, FTIR/DRS, UV-vis/DR, Raman spectroscopy and scanning electron microscopy (SEM).

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The model of nucleation where adsorption of reactant is a rate-limiting step has been considered. Assuming the adsorption range model, a numerical simulation has been made. The dependency of bulk concentration and surface coverage versus time and thermogravimetric curves are presented.

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The results and a numerical simulation of studies on dynamics of the adsorption from seven-component aqueous solution of light chlorinated hydrocarbons on activated carbon have been presented. Aqueous solution of 1,2-dichloroethane (12DCE), 1,1,2,2-tetrachloroethane (S-TET), chloroform (CHCl(3)), carbon tetrachloride (CCl(4)), 1,1-dichloroethene (VDC), perchloroethene (PER) and 1,1,2-trichloroethene (TRI) was used. Concentrations of chlorohydrocarbons were similar as in wastewater from vinyl chloride plant.

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