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Strahlungslose Übertragung von Elektronenanregungsenergie bei zweidimensionalen lumineszierenden Systemen
PublicationAn expression for the photoluminescence (PhL) quantum yield of donors in two-dimensional systems as depending on the concentration ratio nD'/nA' of donors and acceptors has been obtained. In the particular case nD' ⪡ nA' the expression reduces to the form given by other authors. The obtained formula can also be applied to the description of the concentrational quenching of PhL when dimers act as acceptors. The theory has been...
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Aggregation of Rhodamine 6G in titanium dioxide nanolayers and bulk xerogels
PublicationNanolayers and bulk xerogels of Rhodamine 6G (Rh6G) in titanium dioxide (Rh6G/TiO2) were prepared using the sol–gel method. The spectroscopic and structural properties of these two types of hybrid matrices were studied as a function of dye concentration. In both cases absorption, fluorescence and time resolved emission spectra show the formation of fluorescent aggregates. The observed stronger changes in characteristics of bulk...
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Poultry meat freshness assessment based on the biogenic amines index
PublicationIn order to safeguard the well-being of the consumers, it is important to accurately determine the shelf life of poultry and poultry-based products. In this work, it was evaluated whether the measurement of the concentration of cadaverine, putrescine, histamine and tyramine can be used to assess the shelf-life of poultry meat stored in the different types of the containers. Based on the results it can be concluded that the collective...
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Pracujący w czasie rzeczywistym system detekcji gazów wykorzystujący przenośny komputer Raspberry PI oraz matrycę półprzewodnikowych czujników gazu
PublicationThe gas-analyzing systems based on the array of partially selective gas sensors and pattern-recognition techniques are potentially fast and lowcost alternative for other devices, like gas‑analysers. They give the possibility of recognition the type and the concentration of measured volatile compounds in their working environment. In this work we present the implementation of gas recognition system, in which the signals from an...
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Photolytic and Photocatalytic Recreational Water Treatment
PublicationDisinfection is one of the most important steps during recreational water treatment. Nevertheless, disinfection by-products are formed by conventional disinfectants, which pose several health threats. The concentration of disinfection by-products can be decreased by photolytic and photocatalytic treatment. Medium-pressure mercury lamp, UV-LEDs and solar irradiation were investigated and evaluated considering emitted wavelength,...
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Hydration of urea and its derivatives - Volumetric and compressibility studies
PublicationThe densities and sound velocities at T = (288.15, 293.15, 298.15, 303.15 and 308.15) K have been measured for aqueous solutions of urea, N,N-dimethylurea, N,N-diethylurea, N-propylurea, N-butylurea. From these data the apparent molar volumes, V the apparent molar isentropic compressions, KS,, and the Passynski solvation numbers of solutes have been determined. The concentration dependencies of the calculated quantities, their...
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Real-time working gas recognition system based on the array of semiconductor gas sensors and portable computer Raspberry PI
PublicationThe gas-analyzing systems based on the array of partially selective gas sensors and pattern-recognition techniques are potentially fast and low-cost alternative for other devices, like gas analysers. They give the possibility of recognition the type and the concentration of measured volatile compounds in their working environment. In this work we present the implementation of gas recognition system, in which the signals from an...
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Ecotoxicological equilibria of triclosan inMicrotox, XenoScreen YES/YAS, Caco2, HEPG2 and liposomal systems are affected by the occurrence of other pharmaceutical and personal care emerging contaminants
PublicationContaminants of emerging concernmay be considered as any chemicals or factorswhose unintended continuous release and persistence in the environmentmay lead to any observable undesirable response of living beings. Still not much is known on reciprocal toxicological impact of given chemicals when present in binary or more complex mixtures. In thiswork, an attemptwas thus undertaken to study the impact of butylparaben,methylparaben and...
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Scalable Measurement System for Multiple Impedance Gas Sensors
PublicationAuthor proposes scalable architecture of the measurement system for gas sensor with impedance dependance of the gas concentration. The main part of the system is a single-board impedance analyser. The number of analysers working in parallel can be configured according to specific application. The system is controlled by a single computer which organises the measurement cycle and store the acquired measurement data. The system is...
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The influence of reactions conditions on aggregation of dyes used in biochemistry
PublicationSelf-association of dyes and related substances is a very important phenomenon in many fields of applied chemistry. It is also fundamental model reaction of many kinds of molecular interactions such as the micelle formation of amphiphilic substances and the binding of small organic molecules to macromolecules. In spite of many studies concerning the dimerization equilibria of dyes and related substances, the mechanism seems not...
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Technical State Assessment of Charge Exchange System of Self-Ignition Engine, Based On the Exhaust Gas Composition Testing
PublicationThis paper presents possible use of results of exhaust gas composition testing of self - ignition engine for technical state assessment of its charge exchange system under assumption that there is strong correlation between considered structure parameters and output signals in the form of concentration of toxic compounds (ZT) as well as unambiguous character of their changes. Concentration of the analyzed ZT may be hence considered...
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Investigation of the Antifungal Activity and Mode of Action of Thymus vulgaris, Citrus limonum, Pelargonium graveolens, Cinnamomum cassia, Ocimum basilicum, and Eugenia caryophyllus Essential Oils
PublicationThe antimicrobial activity of plant oils and extracts has been recognized for many years. In this study the activity of Thymus vulgaris, Citrus limonum, Pelargonium graveolens, Cinnamomum cassia, Ocimumbasilicum, and Eugenia caryophyllus essential oils (EOs) distributed by Pollena Aroma (Nowy Dwór Mazowiecki, Poland) was investigated against a group of 183 clinical isolates of C. albicans and 76 isolates of C. glabrata. All of...
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Optimization of Saccharification Conditions of Lignocellulosic Biomass under Alkaline Pre-Treatment and Enzymatic Hydrolysis
PublicationPre-treatment is a significant step in the production of second-generation biofuels from waste lignocellulosic materials. Obtaining biofuels as a result of fermentation processes requires appropriate pre-treatment conditions ensuring the highest possible degree of saccharification of the feed material. An influence of the following process parameters were investigated for alkaline pre-treatment of Salix viminalis L.: catalyst concentration...
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The Anti-Staphylococcal Potential of Ethanolic Polish Propolis Extracts
PublicationAbstract: The principal objective of this study was to determine the anti-staphylococcal potential of ethanol extracts of propolis (EEPs). A total of 20 samples of propolis collected from apiaries located in different regions of Poland were used in the study. The two-fold broth microdilution method revealed some important differences in the antimicrobial activity of investigated EEPs. Up to the concentration of 4096 µg/mL no activity...
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Zirconia-based mixed potential sensor with Pt electrode prepared by spin-coating of polymeric precursor
PublicationMany types of yttria-stabilized zirconia (YSZ) based gas sensors have been explored extensively in recent years. Great attention have been directed to mixed-potential-type gas sensors. It is due to growing concerns with environmental issues. Not without a significance is the fact of very attractive performance of this type of sensor allowing to detect low concentration of pollutant gases. In this paper two types of YSZ based mixed-potential...
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Effect of alkyl sulfate on the phase behavior of microemulsions stabilized with monoacylglycerols
PublicationIn this study the effect of an anionic surfactant (sodium dodecyl sulfate SDS) and oils (hydrocarbons: C12-C16) on the formation and phase behavior of the systems of oil/monoacylglycerols (MAG):SDS/propylene glycol/water has been investigated. The effects of the surfactant mixture on the phase behavior and the concentrationof water or oil in the systems were studied at three temperatures (50, 55, 60 C). Electrical conductivity...
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Interactions between polyphenolic antioxidants quercetin and naringenin dictate the distinctive redox-related chemical and biological behaviour of their mixtures
PublicationFood synergy concept is suggested to explain observations that isolated antioxidants are less bioactive than real foods containing them. However, mechanisms behind this discrepancy were hardly studied. Here, we demonstrate the profound impact of interactions between two common food flavonoids (individual: aglycones quercetin—Q and naringenin—N− or their glycosides rutin—R and naringin—N+ vs. mixed: QN− and RN+) on their electrochemical...
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Sources and composition of chemical pollution in Maritime Antarctica (King George Island), part 2: Organic and inorganic chemicals in snow cover at the Warszawa Icefield
PublicationThe study area is located on King George Island, where 90% of the area is permanently glaciated. This study provides a comprehensive analysis of the inorganic and organic chemistry of snow cover in the icefield and a comparison against previous results obtained in fresh water. Snow samples were collected in the summer of 2017 in the Warszawa Icefield area. Sampling points are located along two transects: between the Arctowski Polish...
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Management of Dark Fermentation Broth via Bio Refining and Photo Fermentation
PublicationLignocellulose and starch-based raw materials are often applied in the investigations regarding biohydrogen generation using dark fermentation. Management of the arising post-fermentation broth becomes a problem. The Authors proposed sequential processes, to improve the efficiency of both hydrogen generation and by-products management carried under model conditions. During the proposed procedure, the simple sugars remaining in...
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Fatty acyl benzamido antibacterials based on inhibition of DnaK-catalyzed protein folding
PublicationWe have reported that the hsp70 chaperone DnaK from Escherichia coli might assist protein folding by catalyzing the cis/trans isomerization of secondary amide peptide bonds in unfolded or partially folded proteins. In this study a series of fatty acylated benzamido inhibitors of the cis/trans isomerase activity of DnaK was developed and tested for antibacterial effects in E. coli MC4100 cells. Nα-[Tetradecanoyl-(4-aminomethylbenzoyl)]-l-asparagine...
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Evaluation of antimicrobial activities of powdered cuttlebone against Klebsiella oxytoca, Staphylococcus aureus, and Aspergillus flavus
PublicationBackground: The presence of medicines in the environment is considered as a serious threat to the human health. The entrance of these substances into the water sources causes soil pollution, which eventually leads to the environmental pollution and it creates some problems for the public health. Also, increasing antibiotic resistant bacteria has attracted the attention of researchers to the use of natural resources such as marine...
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Evaluation of citric acid corrosion inhibition efficiency and passivation kinetics for aluminium alloys in alkaline media by means of dynamic impedance monitoring
PublicationA novel approach is proposed for constructing the adsorption isotherm in corrosion studies, based on a well-known interaction between citric acid and aluminium in alkaline electrolytes. Our approach utilizes the instantaneous impedance measurements via Dynamic Electrochemical Impedance Spectroscopy in galvanostatic mode (g-DEIS). Unlike other common tools, g-DEIS delivers exact information about the concentration required for full...
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DETERMINATION OF SURFACTANTS IN ENVIRONMENTAL SAMPLES. PART II. ANIONIC COMPOUNDS
PublicationSurfactants (SAA) with negative charge of polar group are named as anionic compounds. They are main constituent of most products containing synthetic surfactants. The linear alkylbenzene sulfonates (LAS), alkyl ethoxysulfates (AES) and alkyl sulfates (AS) are typically applied from this class of compounds. Those surfactants are ingredients of household detergents and cleaners, laundry detergents, cosmetic. Moreover they can be...
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Analysis of higher recombination orders in organic bulk heterojunction solar cells
PublicationRecently, it has been experimentally demonstrated that an order of nongeminate recombination exceeds two in some types of organic bulk heterojunction donor-acceptor structures. This result is different than for the case of bimolecular recombination described by Langevin theory. Although several theoretical explanations of this effect have been presented, the origin of higher recombination orders is still questionable. In this work,...
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Improvement of electrochemical action of zinc-rich paints by addition of nanoparticulate zinc
PublicationThe influence of nanosized particles on electrochemical action of standard zinc-rich paints by means of SEM as well as potential and impedance measurements has been investigated. The motivation for doing this was to obtain additional electrical connection between the spherical microparticles themselves and zinc particles and steel substrate. Overall zinc content was at the level of 92% by weight. Samples with different concentration...
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New clicked full agonists of the estrogen receptor β
PublicationA click chemistry approach was used to synthesize a series of 1,4-diaryl-substituted 1,2,3-triazoles designed to behave as estrogen receptor (ER) ligands. We studied their affinities for both receptors α and β, their agonist activities in a cell-based luciferase reporter assay and their effect on the proliferation of the hormone-dependent MCF-7 cell line. We found two compounds (3a and 3c) that behave as selective full agonists...
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Hydrogen sulphide electrocatalytic gas sensor
PublicationIn this article measurement results of the electrocatalytic gas sensor in different concentrations of hydrogen sulphide are presented. Working principle of such sensor is based on electric current acquisition, while voltage ramp is applied to the sensor. During voltage sweep oxidation and reduction reactions occurs on the sensor electrodes. Obtained current-voltage plot has unique shape connected...
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Gulf of Gdańsk monitoring conducted by the Institute of Oceanography, University of Gdańsk, in 1981-1994
Open Research DataResults of the monitoring of the Gulf of Gdańsk environment are included in this archival data set. The measurements were conducted by the Institute of the Oceanography of the University of Gdańsk (IO UG) from 1981 till 1994 at the fixed sampling stations covering the area located between Hel Peninsula and the coast of the Gulf of Gdańsk, which extended...
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The study of the influence of ZnO nanoparticles on pyocyanin production - the optimization of production and the study of the physiological response of the cells
Open Research DataThis dataset presents the in-depth analysis of the influence of zinc oxide nanoparticles on pyocyanin production.
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Studies on the formation of formaldehyde during 2-ethylhexyl 4-(dimethylamino)benzoate demethylation in the presence of reactive oxygen and chlorine species
PublicationIn order to protect the skin from UV radiation, personal care products (PCPS) often contain chemical UV-filters. These compounds can enter the environment causing serious consequences on the water ecosystems. The aim of this study was to examine, the effect of different factors, such as UV light, the presence of NaOCl and H2O2 on the formaldehyde formation during popular UV filter, 2-ethylhexyl 4-(dimethylamino)benzoate (ODPABA)...
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Radioactivity of drilling cuttings from shale resources of the Lower Paleozoic Baltic Basin, Poland
PublicationFractionated drilling wastes originating from shale gas exploration in the Baltic Basin in Pomerania were subjected to the measurements of mean activity concentrations of naturally occurring radioactive materials (NORMs).To better understand rock structure and texture, the X-ray diffraction analysis (XRD) and scanning electron microscopy(SEM) observation were used. To compare activity concentration of radionuclides in bulk wastes...
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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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Controlling the size and morphology of precipitated calcite particles by the selection of solvent composition
PublicationCalcium carbonate particles were obtained in the reaction of calcium hydroxide with carbon dioxide at 65°C. Initial Ca(OH)2 suspensions were prepared in pure water and aqueous solutions of ethylene glycol or glycerol of the concentration range up to 20% (vol.). The course of reaction was monitored by conductivity measurements. Precipitated solids were analyzed by FTIR, XRD, SEM and the particles size distribution was determined...
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Monitoring of odors emitted from stabilized dewatered sludge subjected to aging using proton transfer reaction–mass spectrometry
PublicationOne of the potential emission sources of odorous compounds from wastewater treatment plants is sludge processing. The odorous compounds released from dewatered sludge can result in odor nuisance. This study concerns the use of flux hood chamber combined with proton transfer reaction—time of flight—mass spectrometry (PTR-MS) technique for periodical monitoring of odorous compounds emitted from aged, stabilized dewatered sludge samples...
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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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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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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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MINERAL CONTENT OF TREE SAP FROM THE SUBCARPATHIAN REGION
Publicationbut also as medicinal substance in folk medicine. Traditionally, it was used to treat various conditions, mostly anaemia and chronic fatigue. This study has been designed to establish the content of metallic elements (sodium, potassium, calcium, magnesium, zinc and copper) in sap collected from eight different species (silver birch, downy birch, hornbeam, Norway maple, boxelder maple, black walnut, black alder and white willow)...
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Analiza osadów dennych pod kątem ich właściwości nawozowych
PublicationThe analysis of bottom sediments in terms of their fertilizing properties. In paper the characterize of sediments as product to nature usage was done. Analyzed material was taken from ecological treatment system located in wastewater treatment plant in Swarzewo (Pomerania Region) about flow Q= 6000 m3/d. Measurements of dry matter and organic matter content, as well as nitrogen concentrations and phosphorus fractions: loosely...
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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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Perfectly Wetting Mixtures of Surfactants from Renewable Resources: The Interaction and Synergistic Effects on Adsorption and Micellization
PublicationThis paper presents a study of the surface properties of mixtures of surfactants originating from renewable sources, i.e., alkylpolyglucoside (APG), ethoxylated fatty alcohol (AE), and sodium soap (Na soap). The main objective was to optimize the surfactant ratio which produces the highest wetting properties during the analysis of the solution of the individual surfactants, twoand three-component mixtures, and at different pH values....
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Estimating the Impact of Inflow on the Chemistry of Two Different Caldera Type Lakes Located on the Bali Island (Indonesia)
PublicationThis paper is a preliminary attempt to assess the composition of pollutants in two different caldera lakes situated in the Indonesian Archipelago: Batur and Bratan. Both lakes are characterized by largely different physico-chemical regimes; Batur Lake is located in an area that is currently volcanically active, unlike Bratan Lake. The latter is much smaller and shallower than Batur Lake. The concentration of pollutants in the Indonesian...
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Numerical modeling of PFAS movement through the vadose zone: Influence of plant water uptake and soil organic carbon distribution
PublicationIn this study, we investigated the effects of soil organic carbon (SOC) distribution and water uptake by plant roots on PFAS movement in the vadose zone with a deep groundwater table under temperate, humid climate conditions. Two series of numerical simulations were performed with the HYDRUS computer code, representing the leaching of historical PFOS contamination and the infiltration of water contaminated with PFOA, respectively. We...
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The chemistry, properties and performance of flame-retardant rubber composites: Collecting, analyzing, categorizing, machine learning modeling, and visualizing
PublicationRubbers combine the flexibility with mechanical strength, supporting myriad applications, but suffer from inherent flammability. Formulation and production of flame-retardant rubber composites (FRRCs) have intensively been practiced over years, but not comprehensively reviewed. This necessity has outlined collecting, analyzing, screening, classifying, and interpreting the literature with the aim of classifying the FRRCs. We quantified...
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Development of an asymmetric cellulose acetate-ionic liquid P6,6,6,14[PHOS] gel membrane for the perstraction of succinic acid from a model fermentation solution of yarrovia lipolytica
PublicationThis study introduces a novel approach to separate succinic acid (SA) from fermentation mixtures using an asymmetric membrane based on the gelation of the ionic liquid [P6,6,6,14][PHOS] coated with two layers of cellulose acetate. The membrane was designed to explore the synergistic effect of polymer-ionic liquid interfaces according to the solution-diffusion theory. The gelation of the ionic liquid was achieved using 12-hydroxystearic...
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Electrochemical cobalt oxidation in chloride media
PublicationThe green transition, despite recent advances in cobalt-free battery technologies, is still highly dependent on the availability of critical cobalt-based materials. Consequently, there has been increasing interest towards the development of new methods that maximize critical metals recovery from industrial hydrometallurgical solutions. In the current study, direct anodic oxidation of cobalt species from cobalt chloride solutions...
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MnWO4/reduced graphene oxide-based electrochemical sensing platform for simultaneous detection of catechol and resorcinol
Publicationn this study, a novel electrochemical sensor for accurate and sensitive catechol determination was demonstrated employing a screen-printed graphite electrode (SPGE) modified with MnWO4/reduced graphene oxide (MnWO4/rGO) nanocomposite. The MnWO4/rGO nanocomposite has been successfully prepared by using hydrothermal technique, and it was then characterized using several microscopic and spectroscopic methods (XRD, FE-SEM, and EDS)....
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Modeling and optimization of chemical-treated torrefaction of wheat straw to improve energy density by response surface methodology
PublicationToday, torrefaction is important technique for extending the potential of biomass for improvement of energy density. The independent variables investigated for torrefaction study were temperature, retention time, acid concentration, and particle size. The experiment was designed by central composite design (CCD) method using design expert (version 11). The three dependent variables were higher heating value (HHV), energy enhancement...
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Ukrainian Market of Electrical Energy: Reforming, Financing, Innovative Investment, Efficiency Analysis, and Audit
PublicationThe aim of this research is to determine the influence of electrical energy market regulation reform in Ukraine on the competitive environment, the reproduction processes of financial and innovative support, and the energy efficiency of the national economy. The authors have put forward and verified the hypothesis that, under conditions of institutional maturity of the Ukrainian electrical energy market, its liberalization and...
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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...