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Potentiometric sensor containing set of ion selective electrodes with lipid modified membranes for quality assessment of tested non-alcoholic beverages
PublicationPotentiometric sensors may be a good tool for fast quality control of commercial drinks. In this work, such a sensor, containing a set of ion-selective electrodes with lipid-modified membranes (benzylhexadecyldimethylammonium chloride monohydrate, hexadecylamine, 1-dodecanol, elaidic acid, cholesterol) was used for discrimination and quality control of non-alcoholic beverages, mainly composed of sugar and citric acid. It was found...
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The importance of CEFTA 2006 for Western Balkan countries
PublicationFree foreign trade is one of the most important issues all over the world. The impact of bilateral trade can be studied both from economic as well as political perspectives; when it improves economic development, it also creates the conditions for international stability. The aim of the article is to conduct a comparison of the changes to export trade flow in the Central European Free Trade Agreement 2006, with reference to countries...
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Influence of dissolved organic nitrogen on surface waters
PublicationThe aim of this study was to determine the susceptibility of dissolved organic nitrogen (DON) contained in biologically treated wastewater disposed from municipal wastewater treatment plants (WWTPs) to biodegradability and bioavailability in a water environment. Additionally an evaluation was performed of the participation of this organic nitrogen fraction, including bioavailable DON (bDON), in the nitrogen balance for the Baltic...
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The possibility of use by-products for synthesis of emulsifiers
PublicationIn the last years the interest in use of materials originated from natural sources, e.g. vegetables to produce attractive products still grows. According to that, also the synthesis of these products should be adequate to the green chemistry requirements. The typical example observed in recent years focuses on utlization of bioglycerol - the by - product of global biodiesel manufacturing. The still growing production of biodiesel...
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Myrosinase activity in different plant samples; optimisation of measurement conditions for spectrophotometric and pH-stat methods
PublicationMyrosinase found in Brassicaceae plants, is the enzyme responsible for hydrolysis of glucosinolates. As a result a variety of biologically active metabolites are liberated, whose importance in crop protection and especially in cancer chemoprevention is rapidly gaining recognition. The growing practical application of glucosinolate degradation products requires that sensitive and reliable methods of myrosinase activity determination...
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Structure of Microemulsion Formulated with Monoacylglycerols in the Presence of Polyols and Ethanol
PublicationThe influence of polyols as cosurfactants (propylene glycol PG; glycerol G) and short chain alcohol as a cosolvent (ethanol EtOH) on the formation and solubilization capacity of the systems: hexadecane/monoacylglycerols (MAG)/polyol/water:EtOH, at 60C, was investigated. Electrical conductivity measurement, and the DSC method were applied to determine the structure and type of microemulsions formed. The dimension of the droplets...
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Homogeneous nucleation rate of methane hydrate formation under experimental conditions from seeding simulations
PublicationIn this work, we shall estimate via computer simulations the homogeneous nucleation rate for the methane hydrate at 400 bars for a supercooling of about 35 K. The TIP4P/ICE model and a Lennard-Jones center were used for water and methane, respectively. To estimate the nucleation rate, the seeding technique was employed. Clusters of the methane hydrate of different sizes were inserted into the aqueous phase of a two-phase gas–liquid...
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N-doped carbon nanospheres as selective fluorescent probes for mercury detection in contaminated aqueous media: chemistry, fluorescence probing, cell line patterning, and liver tissue interaction
PublicationA precise nano-scale biosensor was developed here to detect Hg2+ in aqueous media. Nitrogen-doped carbon nanospheres (NCS) created from the pyrolysis of melamine–formaldehyde resin were characterized by FESEM, XRD, Raman spectra, EDS, PL, UV–vis spectra, and N2 adsorption–desorption, and were used as a highly selective and sensitive probe for detecting Hg2+ in aqueous media. The sensitivity of NCS to Hg2+ was evaluated by photoluminescence...
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Optimized photodegradation of palm oil agroindustry waste effluent using multivalent manganese–modified black titanium dioxide
PublicationThis article presents a methodological approach to use manganese (Mn3+Mn7+)-modified black titanium dioxide (Mn/BTiO2) as a photocatalyst to optimize and improve visible-light-driven photodegradation of treated agro-industrial effluent (TPOME). A modified wet chemical process was used to prepare BTiO2. The BTiO2 was then wet impregnated with Mn and calcined at 300 °C for 1 h to produce Mn/BTiO2. The activity of Mn/BTiO2 was investigated...
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Modelling the impact of the agricultural holdings and land-use structure on the quality of inland and coastal waters with an innovative and interdisciplinary toolkit
PublicationThe changes taking place in the marine coastal zones are extremely important, as about 40% of the human population currently lives in the coastal areas (within 100 kilometres of the coastline) increasing anthropogenic pressure on the marine ecosystems. Agriculture is a significant source of nutrients to the marine environment that increase hypoxia, eutrophication and may pose a threat to the services provided by ecosystems. In...
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Toward the next generation of air quality monitoring: Mercury
PublicationMercury is a global pollutant that is ubiquitous in the environment. Enrichment of mercury in the biosphere as the result of human activities and subsequent production of methylmercury (MeHg) has resulted in elevated concentrations in fish, wildlife and marine mammals globally. Elemental mercury (Hg0) is the most common form of mercury in the atmosphere, and the form that is most readily transported long distances from its emission...
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Treated wasetewater as a source of humic substances in surface waters
PublicationHumic substances impose substantial effect on the aquatic environment as well as the water organisms and human health. Among other features, the humic acids determine organoleptic properties of surface waters. Therefore explanation of the origin and properties of humic acids in surface waters is one of the priorities of water technology.Recently it was pointed out that in the wastewater treatment process organic compounds characterized...
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Mobile monitoring system for gaseous air pollution
PublicationThe concept of a mobile monitoring system for chemical agents control in the air is presented. The proposed system can be applied to measure industrial and car traffic air pollution. A monitoring station is relatively small and can be placed on cars or public transportation vehicles. Measured concentrations of air pollutants are collected and transferred via the GSM network to a central data base. Exemplary results from a measurement...
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E-technologie w edukacji i terapii dzieci z autyzmem w Polsce
PublicationArtykuł dotyczy możliwości wsparcia technologiami informacyjnymi edukacji i terapii dzieci z za - burzeniami rozwoju ze spektrum autyzmu. Szczególna uwaga zostanie poświęcona aplikacjom przeznaczonym na urządzenia mobilne (tablety). Artykuł podsumowuje przesłanki zastosowania tabletów w pracy z dziećmi auty - stycznymi oraz pokazuje kategorie aplikacji, jakie mogą wspierać terapię i edukację dzieci. Zostały przedstawione wyniki...
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Zastosowanie addytywów w separacji pianowej białek serwatkowych i białek mlecznych
PublicationZaproponowano proces separacji pianowej do wydzielania białek ze strumieni poprodukcyjnych przemysłu mleczarskiego Ponadto zaproponowano zastosowanie w separacji pianowej białek serwatkowych i mlecznych addytywów dopuszczonych ustawą do stosowania w żywności. Jako cel pracy przyjęto uzyskanie wyników uzasadniających wybór takich addytywów, które intensyfikują przebieg i polepszają wynik procesu separacji pianowej białek. W części...
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PERFORMANCE OF THE PVT SOLAR COLLECTOR OPERATED WITH WATER –AL2O3 NANOFLUID
PublicationAn experimental investigation of the hybrid module photovoltaic panel -solar collector (PVT) cooled by water-Al2O3 nanofluids has been conducted. The weight fractions of the nanoparticles were 1% and 3%. Thermal efficiency, power efficiency and overall efficiency have been determined for artificial source of light and sunlight. No noticeable effect of the nanoparticle concentration on the overall efficiency of the PVT module has...
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Performance of the PVT solar collector operated with water-Al2O3 nanofluid
PublicationAn experimental investigation of the hybrid module photovoltaic panel -solar collector (PVT) cooled by water-Al2O3 nanofluids has been conducted. The weight fractions of the nanoparticles were 1% and 3%. Thermal efficiency, power efficiency and overall efficiency have been determined for artificial source of light and sunlight. No noticeable effect of the nanoparticle concentration on the overall efficiency of the PVT module has...
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Optical properties of boron-doped nanocrystalline diamond films studied by spectroscopic ellipsometry
PublicationThe optical properties of boron-doped nanocrystalline diamond films, coated using Microwave Plasma Enhanced Chemical Vapour Deposition (μPE CVD) system, were analyzed by spectroscopic ellipsometry. Diamond films were deposited on silicon substrates. The ellipsometry data (refractive index (n(λ)), extinction coefficient (k(λ)) were modeled using dedicated software. Evolution of the optical structure with boron doping was observed...
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High order of nongeminate recombination in organic bulk heterojunction solar cells
PublicationWe analyze high order of nongeminate recombination in organic donor–acceptor bulk heterojunction solar cells. The model of recombination where an exciton annihilates on an electron–hole Langevin bound pair near donor–acceptor interface has been applied in our studies. We obtained satisfactory agreement between experimental results and theoretical calculations for the concentration dependences of several parameters characterizing...
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Synthesis and application of tetrazole di and triamide derivatives in ion-selective membrane electrodes
PublicationA number of tetrazole diamides and triamides have been synthesized and applied as ion carries in ion-selective membrane electrodes. Their selectivity and sensitivity were studied towards alkali, alkaline earth, transition and heavy metal cations. it was found that membranes doped with 3 and 2-nitrophenyl octyl ether exhibit an almost theoretial Nernstian response for NH+ over relatively wide concentration range. Elestrodes with...
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Construction and investigation of SO2 amperometric sensor with a solid polymer electrolyte membrane
Publicationn this paper a sensor for detection of the sulphur dioxide based on three electrode cell configuration with a liquid electrolyte, a mercury sulphate reference electrode and a solid polymer electrolyte working electrode is presented. Working elec- trode was obtained by using Takenaka-Torikai chemical deposi- tion method by precipitation of Au particles into the pores of the Nafion membrane. Sensors characteristics measurements were...
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Correlations between the wear of car brake friction materials and airborne wear particle emissions
PublicationAirborne wear particles emitted from transport vehicle brakes are one of the main sources of toxic metals in inhalable particulate matter. Prediction of wear particle emissions may become more accurate if the relationship between the wear and particle emission characteristics is known. An experimental study was performed to investigate proportional correlations between the mass wear, 0.01–0.42 μm particle emission measured by a NanoScan...
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Annual variability of heavy metal content in Svalbard reindeer faeces as a result of dietary preferences
PublicationDuring both winter and summer, Svalbard reindeer selectively feed on different types of vegetation that are not only a source of nutritional value, but also a place of heavy metal accumulation. In the present study, the content of cadmium, chromium, copper, iron, lead, nickel, manganese, and zinc in reindeer excrement was measured. The main aims were to determine the seasonal content of several heavy metals in Svalbard reindeer...
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Do You Know What You Drink? Comparative Research on the Contents of Radioisotopes and Heavy Metals in Different Types of Tea from Various Parts of the World
PublicationThe aim of this study was to assess the potential health risks of radioactive elements and heavy metals ingested through the consumption of various types of tea imported to the Polish market (black, green, red, oolong and white). The concentrations [Bq/kg] of radionuclides (40K, 137Cs, 226Ra, 210Pb and 228Th) in tea leaves before and after brewing were measured using γ-ray spectrometry with high-purity germanium (HPGe). The concentrations...
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Evaluating the antibacterial activity of muramyl dipeptide derivatives, retro-tuftsin derivatives, and anthraquinone oligopeptides against a range of pathogenic bacteria
PublicationSearch for new and efficient antibiotic is crucial because of microbial drug resistance and problems with side effects of the administered medication. In this study, we evaluate the in vitro microbiological activity of muramyl dipeptide derivatives, retro-tuftsin derivatives (i.e., tuftsin with reversed amino acid sequences), and combinations of retro-tuftsin derivatives with substituted anthraquinones. The potency of the investigated...
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Peptydy penetrujące – rodzaje i mechanizmy przenikania przez błony komórkowe
PublicationPeptydy penetrujące z pewnością są wyjątkową i ciekawą grupą związków peptydowych. Zostały odkryte ponad dwadzieścia lat temu, ale wiedza na ich temat wciąż jest rozbudowywana. Liczne badania nad mechanizmami ich przenikania do wnętrza komórek pozwalają zrozumieć jakie cechy strukturalne warunkują ich zdolność do penetracji komórek. Wiedza ta pozwala na projektowanie nowych, bardziej efektywnych peptydów penetrujących., które mogą...
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Assessment of diversity and composition of bacterial community in Sludge Treatment Reed Bed systems
PublicationDue to their low emission of odours and lack of the need to apply additional chemical agents, sludge treatment reed beds (STRBs) constitute an economically feasible and eco-friendly approach to sewage sludge management. Correctly designed and operated STRBs ensure effective reduction of the dry matter content coupled with the mineralisation of organic compounds. Successful operation of STRBs relies on complex interactions between...
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Nitrogen pathways during sewage treatment in constructed wetlands in temporary climate
PublicationThe objectives of this paper is to estimate the role and quantity of the unit process responsible for removal or/and retention of nitrogen in different types of constructed wetlands in vegetation season and outside vegetation season. To estimate the role of the plant two objects inhabited one with willow and the other with reed were selected to assessment. Among anthers it was indicated that the concentrations of contamination...
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Exposure of a small Arctic seabird, the little auk (Alle alle) breeding in Svalbard, to selected elements throughout the course of a year
PublicationThe Arctic marine ecosystem can be altered by processes of natural and anthropogenic origin. Spatio-temporal variation in species exposure to contamination is still poorly understood. Here, we studied elemental concentrations in the non-lethally collected samples from the most numerous seabird in European Arctic, the little auk (Alle alle) nesting in one breeding colony in Svalbard. This seabird spent the breeding season in the...
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High-temperature kinetics study of 430L steel powder oxidized in air at 600–850 °C
PublicationThe 430L stainless steel powder with a mean particle size of 95 μm was studied to determine its high-temperature oxidation properties. Continuous thermogravimetric measurements were carried out for 100 h in air at temperatures in the range of 600–850 °C. Even though a considerable amount of Cr (up to ˜5 wt.% Cr) inside the grains was depleted – especially inside small grains – no breakaway oxidation was observed. This indicates...
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Characterization of various drinking waters by new potentiometric taste sensor with lipid, lipid-like polymer membranes
PublicationA new sensing system comprising five all-solid-state electrodes with lipid, lipid like-polymer membranes was applied for rapid qualitative and quantitative analysis of various drinking waters. The results elaborated by chemometric methods revealed sensitivity to CO2 content in drinking water, suggesting that this sensing system could be used as a taste sensor. The ability of taste sensor to perform quantitative analysis of minerals...
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Time-frequency analysis of acoustic signals using concentrated spectrogram
PublicationThe paper presents improved method of time-frequency (TF) analysis of discrete-time signals. The method involves signal's local group delay (LGD) and channelized instantaneous frequency (CIF) to purposely redistribute all Short-time Fourier transform (STFT) lines. Additionally, the energy concentration index (ECI) and some histogram-like statistics are used to evaluate readability of estimated TF distributions of the energy. Recorded...
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Thermally activated persulfate-based Advanced Oxidation Processes — recent progress and challenges in mineralization of persistent organic chemicals: a review
PublicationThermally activated persulfate (TAP) finds application in Advanced Oxidation Processes for the removal of pollutants from contaminated water and soil. This paper reviewed the various cases of TAP in the environmental remediation. The pollutants such as individual pharmaceuticals, biocides, cyclic organic compounds, and dyes are considered in this review. It is interesting to note that most of the organic compounds undergo complete...
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Emulsifi ers from renewable materials: an eco-friendly synthesis and properties
PublicationThe focus of this study was the preparation of novel bio based polyglycerol emulsifiers characterized by a one pot synthesis, thus by modified properties with respect to interfacial activity and effectiveness as emulsion stabilizers. The final products of the esterification process, carried out in the presence of carboxylates were used directly as emulsifiers (without purification or fractionation). Polyglycerol emulsifiers obtained...
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Polypyrrole based gas sensor for ammonia detection
PublicationThe nature of polypyrrole response to toxic gases does not allow using the sensor in a conventional way. The main aim of this study is to acquire the information about the concentration using different approaches: a linear approximation, a non-linear approximation and a tangent method. In this paper a two-steps procedure for sensor response measurements has been utilized. Polypyrrole films were electrochemically synthesized on...
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The bile salt/phospholipid ratio determines the extent of in vitro intestinal lipolysis of triglycerides: Interfacial and emulsion studies
PublicationThis study focused on the protein-stabilised triglyceride (TG)/water interfaces and oil-in-water emulsions, and explored the influence of varying molar ratios of bile salts (BSs) and phospholipids (PLs) on the intestinal lipolysis of TGs. The presence of these two major groups of biosurfactants delivered with human bile to the physiological environment of intestinal digestion was replicated in our experiments by using mixtures...
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Characteristics of Cucumis metuliferus, Actinidia deliciosa and Musa paradisica fragrance profiles using a comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometric detection (GC×GC-TOF MS)
PublicationComprehensive two-dimensional gas chromatography with time-of-flight mass spectrometric detection (GC×GC-TOF-MS) is a modern analytical technique used in many fields. This technique enables an effective separation of volatile chemical compounds [1]. In recent years, the topic of healthy food and healthy living has become very popular. For this reason, more and more scientific publications related to the analysis of food products...
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Presence of antibiotics in the aquatic environment in Europe and their analytical monitoring: Recent trends and perspectives
PublicationThe presence of antibiotics and their metabolites in the aquatic environment exerts a negative impact on all organisms. Moreover, the easy migration of these substances to drinking water may also have serious consequences for public health, such as drug resistance. Although antibiotics and their metabolites are detected in surface waters and wastewater, there are still no systemic solutions preventing environmental pollution with...
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Methods of Assessment of Metal Contamination in Bottom Sediments (Case Study: Straszyn Lake, Poland)
PublicationThe concentrations of six metals (Zn, Cu, Pb, Ni, Cr, and Cd) were investigated in bottom sediments of Straszyn Lake (North Poland). This study was designed to determine a total content of metals and to assess their mobility and bioavailability. The sequential extraction was used to fractionate metals into five fractions: exchangeable, bound to carbonates, bound to Fe–Mn oxides, bound to organic matter, and residual. The evaluation...
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The comparison of antioxidant properties and nutrigenomic redox-related activities of vitamin C, C-vitamers, and other common ascorbic acid derivatives
PublicationThe term ‘vitamin C’ describes a group of compounds with antiscorbutic activity of L-ascorbic acid (AA). Despite AA’s omnipresence in plant-derived foods, its derivatives have also been successfully implemented in the food industry as antioxidants, including the D-isomers, which lack vitamin C activity. This study aimed to determine the relationship between redox-related activities for five derivatives of AA using electrochemical,...
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α-Pinene, 3-carene and d-limonene in indoor air of Polish apartments: The impact on air quality and human exposure
PublicationMonoterpenes are among most ubiquitous volatile organic compounds (VOCs) to be detected in indoor air. Since the quality of indoor air is considered important for inhabitants' well-being, the present study aimed at investigating impact of human activity on levels of selected monoterpenes applying passive sampling technique followed by thermal desorption and gas chromatography coupled mass spectrometry. One of the objectives of...
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Problems of modelling toxic compounds emitted by a marine internal combustion engine for the evaluation of its structure parameters
PublicationThe paper presents the possibility of using an analytical study of the engine exhaust ignition to evaluate the technical condition of the selected components. Software tools available for the analysis of experimental data commonly use multiple regression model that allows the study of the effects and iterations between model input quantities and one output variable. The use of multi-equation models gives a lot of freedom in the...
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Understanding the origin of high corrosion inhibition efficiency of bee products towards aluminium alloys in alkaline environments
PublicationVarious bee products were found to be efficient corrosion inhibitors of aluminium in different environments. In particular, bee pollen was found to be highly effective in alkaline electrolytes, yet its highly complex composition and possible synergistic interactions hinder determination of the compounds acting as active corrosion inhibitors. The main purpose of the following work is to investigate the effect of solvents used for...
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Elemental composition, environment of deposition of the Lower Carboniferous Emma Fiord Formation oil shale in Arctic Canada
PublicationThe sedimentary succession of 51-m consisting of a thin coal seam (1 m) and oil shale with a marlstone and carbonate-mudstone matrix of the Lower Carboniferous (Viséan) Emma Fiord Formation located on the Grinnell Peninsula, Devon Island, Arctic Canada was examined. The techniques used include reflected light microscopy, and instrumental neutron activation analysis (INAA) for elemental concentration, and inductively coupled plasma...
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The effect of Ag, Au, Pt, and Pd on the surface properties, photocatalytic activity and toxicity of multicomponent TiO2-based nanomaterials
PublicationMulticomponent TiO2-based nanomaterials (MC-NMs) show better physicochemical properties than their individual components or bulk materials. However, the same unique properties that offer innovative applications might also pose unknown risks to human health and the environment. In this context, TiO2- based nanomaterials with a mixture of noble metal precursors (Ag, Au, Pt, and Pd) for large-scale technological applications in air...
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Modeling of pharmaceuticals mixtures toxicity with deviation ratio and best-fit functions models
PublicationThe present study deals with assessment of ecotoxicological parameters of 9 drugs (diclofenac (sodium salt), oxytetracycline hydrochloride, fluoxetine hydrochloride, chloramphenicol, ketoprofen, progesterone, estrone, androstenedione and gemfibrozil), present in the environmental compartments at specific concentration levels, and theirmutual combinations by couples against Microtox® and XenoScreen YES/YAS® bioassays. As the quantitative...
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Potential of nanocomposites of zero valent copper and magnetite with Eleocharis dulcis biochar for packed column and batch scale removal of Congo red dye
PublicationThe current study is the first attempt to prepare nanocomposites of Eleocharis dulcis biochar (EDB) with nano zero-valent Copper (nZVCu/EDB) and magnetite nanoparticles (MNPs/EDB) for batch and column scale sequestration of Congo Red dye (CR) from synthetic and natural water. The adsorbents were characterized with advanced analytical techniques. The impact of EDB, MNPs/EDB and nZVCu/EDB dosage (1–4 g/L), pH (4–10), initial concentration...
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Expermental investigation on adsorption of methylene blue dye from waste water using corncob cellulose-based hydrogel
PublicationHydrogel from corncob cellulose was synthesized in this investigation. The synthesized Hydrogel was characterized by SEM, XRD, and FTIR instruments. As the results indicate the synthesized hydrogel has required and important features, these suggest the suitability of hydrogel for the adsorption of methylene blue dye (MBD). Three important process variables (dosage, contact time, and initial concentration) with three levels were...
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Influence of iron content on water uptake and charge transport in BaCe0.6Zr0.2Y0.2−xFexO3−δ triple-conducting oxides
PublicationIn this work, we studied the BaCe0.6Zr0.2Y0.2−xFexO3−δ system which belongs to the triple-conducting oxides (TCOs) group. The electrochemical properties of BaCe0.6Zr0.2Y0.2−xFexO3−δ were investigated using electrochemical impedance spectroscopy (EIS) and the water uptake was analyzed using thermogravimetry (TG). All investigated materials exhibited water uptake, with proton concentration increasing with decreasing iron content....
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Modelling AOB-NOB competition in shortcut nitrification compared with conventional nitrification-denitrification process
PublicationIn particular, mainstream deammonification and/or shortened nitrificationdenitrification via nitrite (so-called “nitrite shunt”) is a promising new treatment concept that has the potential to revolutionise how nitrogen removal is achieved at WWTPs. Understanding the role of the AOB/NOB competition in the nitrogen cycle in wastewater treatment systems will change operational strategies of the novel nitrogen removal processes. The...