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Wyniki wyszukiwania dla: fractional bactericidal concentration
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The impedance of hydrogen oxidation reaction in a proton exchange membrane fuel cell in the presence of carbon monoxide in hydrogen stream
PublikacjaEvaluation of performance of a proton exchange membrane fuel cell, which is affected by carbon monoxide that pollutes the hydrogen stream, was presented. This influence was studied for carbon monoxide concentration of 125–325 ppb, which are close to values specified in ISO 14687:2019 standard. Performed studies provided crucial information for further development of fuel cell as an energy source for automotive application. Impedance...
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The Influence of Co-Fermentation of Agri-Food Waste with Primary Sludge on Biogas Production and Composition of the Liquid Fraction of Digestate
PublikacjaEnergy self-sufficiency is a current trend in wastewater treatment plants. This effect can be achieved by increasing the production of electricity from biogas and by reducing energy consumption for technological processes. One idea, in line with the circular economy concept, is the use of waste rich in organic matter as co-substrates for the fermentation process. The aim of this study was to determine the effect of waste co-fermentation...
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Importance of Conjugation of the Bile Salt on the Mechanism of Lipolysis
PublikacjaWe aim to advance the discussion on the significance of the conjugation of bile salts (BS) in our organism. We hypothesize that conjugation influences the rate of lipolysis. Since the rate of lipolysis is a compound parameter, we compare the effect of conjugation on four surface parameters, which contribute to the rate. Since deconjugation is due to gut microbiota, we hypothesize that microbiota may affect the rate of lipolysis....
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Mind the Gender Wage Gap – the Impact of Trade and Competition on Sectoral Wage Difference
PublikacjaThis article examines differences between women’s and men’s wages in 18 selected OECD countries in the period 1970-2005. The study is based on 12 manufacturing sector- and skill-specific sets of panel data on the gender wage gap. We apply a system GMM estimator to the extended version of the conditional gender wage gap convergence equation, controlling for sector concentration and industry-specific measures of openness using a...
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Role of nitrogen in evolution of sp2/sp3 bonding and optical band gap in hydrogenated carbon nitride
PublikacjaDrastic changes in the bonding are found in amorphous hydrogenated carbon nitride (a-CNx:H) film as a function of nitrogen concentration (or N/C ratio). The total C-sp3 fraction and hardness shows a sharp decrease (at N/C = 0.40) whereas optical band gap and resistivity shows a gradual increase as nitrogen concentration increases from 0.07 to 0.58. Raman spectrum of a-CNx:H film is fitted with both Gaussian (integrated intensity...
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Galvanostatic impedance measurements for the efficient adsorption isotherm construction in corrosion inhibitor studies
PublikacjaWe present an approach towards an accurate and time-efficient adsorption isotherm determination to evaluate the corrosion inhibitor interaction in electrolytic environments. The approach is based on dynamic impedance spectroscopy measurements in galvanostatic mode (g-DEIS). The studied corrosion inhibitor is continuously injected between the secondary cell and the corrosion cell. The efficiency corresponding to instantaneous inhibitor...
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Can sodium 1-alkylsulfonates participate in the sodium dodecyl sulfate micelle formation?
PublikacjaThe aggregation behavior of sodium dodecyl sulfate (SDS) was studied in an aqueous solution in the presence of increasing concentrations of selected sodium 1-alkylsulfonates, namely sodium 1-octanesulfonate, sodium 1-decanesulfonate, and sodium 1-dodecanesufonate. The critical micelle concentration (CMC) of SDS was determined by conductivity and fluorescence intensity measurements. The steady-state fluorescence quenching experiments...
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Application of electronic nose to effectiveness monitoring of air contaminated with toluene vapors biofiltration process
PublikacjaThe research presents the application of electronic nose (combined with MLR model) to on-line effectiveness monitoring of biofiltration of air contaminated with hydrophobic, odorous compound (toluene vapors). The research was conducted using two-section biotrickling filter inhabited by Candida environmental isolates. Gas chromatography was used as the comparative technique to obtain reliable quantification of toluene concentration...
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Electrocatalytic Gas Sensor with Reference Layer
PublikacjaThis paper presents studies of gas sensors prepared in ceramic technology with Nasicon as a solid electrolyte. Sensors work in the voltammetric mode thus based on the excitation of a sensor with a periodic potential signal while current response is recorded. The main aim is to investigate a Bi8Nb2O17 reference layer influence on sensor properties. Sensors I-V characteristics in different concentration of nitrogen dioxide have been...
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A comprehensive evaluation of mimosa extract as a corrosion inhibitor on AA6060 alloy in acid rain solution: part I. Electrochemical AC methods
PublikacjaThe inhibition effect of mimosa extract on the corrosion of AA6060 aluminum alloy in acid rain solution was investigated by electrochemical impedance spectroscopy and dynamic electrochemical impedance spectroscopy (DEIS). All the studied electrochemical parameters showed good corrosion inhibitive characteristics with respect to the aluminum alloy in the tested solution. Inhibitor efficiency increased with the concentration and...
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Simultaneous impedance and volumetric studies and additionally potentiodynamic polarization measurements of molasses as a carbon steel corrosion inhibitor in 1M hydrochloric acid solution
PublikacjaThe inhibition effect of molasses on the corrosion of low carbon steel in 1M hydrochloric acid solution was investigated by volumetric and electrochemical measurements. Potentiodynamic polarization and dynamic electrochemical impedance spectroscopy (DEIS) results were obtained and compared with to those, obtained with the hydrogen evolution technique. All results indicate that molasses functioned as a good inhibitor in 1M hydrochloric...
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NOBLE METAL MODIFIED TiO2 FOR PHOTOCATALYTIC AIR PURIFICATION
PublikacjaTiO2 was surface modified with silver, gold, palladium and platinum ion clusters to improve its photocatalytic activity. The effect of metal content, the kind of dopant used during preparation procedure on the photoactivity were investigated. in toluene removal which was used as a model volatile organic compound. Toluene, at the concentration of about 100 ppm, was irradiated over noble metal modified TiO2 using light-emitting diodes...
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SmallAngle Neutron Scattering Study of the Structure of Mixed Micellar Solutions Based on Nonionic and Two Cationic Surfactants
PublikacjaThe aggregation in mixed water systems based on nonionic surfactant, i.e., heptaethylene glycol monotetradecyl ether (C14E7), and cationic surfactants, i.e., cetyltrimethylammonium bromide (CTAB), and cetyltrimethylammonium chloride (CTAC) has been investigated using the smallangle neutron scattering method. The preliminary results of the study of the behavior of C14E7 aqueous solutions (for a concentration of 0.17%) when adding...
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Evolution of chemotaxis in single-cell artificial organisms
PublikacjaThe model of a liquid two-dimensional environment, which is based on physics of diffusion, allows us to simulate the diffusion of morphogenes. Artificial organisms move using a chemotaxis reacting to concentration difference. Organisms are controlled by a gene regulatory network coded in a linear genome and reproduce by division. We made a lot of experiments presenting organisms’ behaviour in various environment conditions. We...
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Trace Elements in Aquatic Environments
PublikacjaA trace element is defined as a chemical element whose the average concentration is less than 100 ppm (mg/kg, mg/L – in the case of a water matrix). In aquatic environments the concentrations of trace elements are usually at the level of picomoles per liter and lower. This causes extreme analytical problems, especially in situations where low content is in the range of background levels. Taking into account the role of trace elements...
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The speciation of selected heavy metals in sewage sludge stabilized in reed basins
PublikacjaThe aim of the work was to determine influence of time on organic matter content, nutrients concentrations as well as speciation of selected heavy metals (Cd, Pb, Ni, Cr, Cu and Zn) in sewage sludge stabilized in reed basins during 7-15 years. The analyzed sewage sludge was collected from reed basins from four municipal WWTPs located in Denmark serving from 9 000 to 40 000 pe in Vallo, Rudkøbing, Nakskov and Helsinge. Sewage...
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Microextraction Techniques Used in the Procedures for Determining Organomercury and Organotin Compounds in Environmental Samples
PublikacjaDue to human activities, the concentrations of organometallic compounds in all parts of the environment have increased in recent decades. The toxicity and some biochemical properties of mercury and tin present in the environment depend on the concentration and chemical form of these two elements. The ever-increasing demand for determining compounds at very low concentration levels in samples with complex matrices requires...
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INVESTIGATION OF ACIDIC SOLUTIONS BY POTENTIOMETRIC TASTE SENSOR WITH ALL SOLID STATE ELECTRODES
PublikacjaPotentiometric taste sensors with electrodes containing lipophilic compound / polymer membranes were already used to distinguish commercial liquid products. In this paper a new potentiometric taste sensor consisting of six All Solid State Electrodes (ASSEs) has been presented. Each of the membrane contains a selected lipophilic compound. The set-up consists of a reference electrode and six ASSEs. The inner layer made of a conducting...
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Study of the Anti-Staphylococcal Potential of Honeys Produced in Northern Poland
PublikacjaThe antimicrobial activity of 144 samples of honeys including 95 products from apiaries located in Northern Poland was evaluated. The antibacterial activity of those natural products, their thermal stability, and activity in the presence of catalase was investigated by microdilution assays in titration plates. The MTT assay was performed for the determination of anti-biofilm activity. Spectrophotometric assays were used for the...
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Investigation of Air Quality beside a Municipal Landfill: The Fate of Malodour Compounds as a Model VOC
PublikacjaThis paper presents the results of an investigation on ambient air odour quality in the vicinity of a municipal landfill. The investigations were carried out during the spring–winter and the spring seasons using two types of the electronic nose instrument. The field olfactometers were employed to determine the mean odour concentration, which was from 2.1 to 32.2 ou/m3 depending on the measurement site and season of the year. In...
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Water Solubilization Using Nonionic Surfactants from Renewable Sources in Microemulsion Systems
PublikacjaIn this study the effect of temperature, NaCl andoils (hydrocarbons: C8-C16) on the formation and solubilizationcapacity of the systems of oil/monoacylglycerols(MAG):ethoxylated fatty alcohols (CEO20)/propylene glycol(PG)/water was investigated. The effects of the surfactantmixture on the phase behavior and the concentration ofwater or oil in the systems were studied at three temperatures(50, 55, 60 C) and with varied NaCl solutions...
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Enhanced boron doping of thin diamond films grown in deuterium-rich microwave plasma
PublikacjaThe boron-doped diamond thin films were growth in deuterium rich microwave plasma in CVD process. The mechanism of influence of plasma composition on boron doping level was studied using optical emission spectroscopy. Deuterium rich plasma results in an increased dissociation of B2H6 precursor and intense boron-radicals' production. In consequence, a higher doping level of diamond films was observed by means of Laser Induced Breakdown...
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Highly Reliable Passive RFID-Based Inductor–Capacitor Sensory System Strengthened by Solvatochromism for Fast and Wide-Range Lactate Detection
PublikacjaA passive radio frequency-identification-based inductor-capacitor (LC) lactate sensory system with a specific dye-containing interdigitated capacitor (IDC) in which the sensing signal is amplified by the solvatochromic effect is proposed. When a lactate solution contacts the IDC of the LC lactate sensor, the capacitance of the IDC changes, changing the resonance frequency of the sensor. This changes the oscillation frequency of...
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Analysis of the Factors Affecting Static In Vitro Pepsinolysis of Food Proteins
PublikacjaIn this meta-analysis, we collected 58 publications spanning the last seven decades that reported static in vitro protein gastric digestion results. A number of descriptors of the pepsinolysis process were extracted, including protein type; pepsin activity and concentration; protein concentration; pH; additives; protein form (e.g., ‘native’, ‘emulsion’, ‘gel’, etc.); molecular weight of the protein; treatment; temperature; and...
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Phenolic compounds from Nerium oleander leaves: microwave assisted extraction, characterization, antiproliferative and cytotoxic activities
PublikacjaA microwave-assisted extraction (MAE) method was used for the extraction of phenolic compounds from Nerium oleander leaves. The influence of variables such as ethanol concentration, microwave power, irradiation time and liquid/solid ratio on polyphenol extraction was modelled using a second-order regression equation based on response surface methodology (RSM). The optimal conditions for MAE were: extraction solvent 35% ethanol...
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Mutual Interaction between Temperature and DO Set Point on AOB and NOB Activity during Shortcut Nitrification in a Sequencing Batch Reactor in Terms of Energy Consumption Optimization
PublikacjaRecently, many wastewater treatment plants (WWTPs) have had to deal with serious problems related to the restrictive requirements regarding the euent quality, as well as significant energy consumption associated with it. In this situation, mainstream deammonification and/or shortened nitrification-denitrification via nitrite (so-called “nitrite shunt”) is a new promising strategy. This study shows the mechanisms and operating conditions...
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Morphology Regulation Mechanism and Enhancement of Photocatalytic Performance of BiOX (X = Cl, Br, I) via Mannitol-Assisted Synthesis
PublikacjaBiOX (X = Cl, Br, I) photocatalysts with dominant (110) facets were synthesized via a mannitol-assisted solvothermal method. This is the first report on the exposed (110) facets-, size-, and defects-controlled synthesis of BiOX achieved by solvothermal synthesis with mannitol. This polyol alcohol acted simultaneously as a solvent, capping agent, and/or soft template. The mannitol concentration on the new photocatalysts morphology...
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Electrochemical determination of nitroaromatic explosives at boron-doped diamond/graphene nanowall electrodes: 2,4,6-trinitrotoluene and 2,4,6-trinitroanisole in liquid effluents
PublikacjaThe study is devoted to the electrochemical detection of trace explosives on boron-doped diamond/graphene nanowall electrodes (B:DGNW). The electrodes were fabricated in a one-step growth process using chemical vapour deposition without any additional modifications. The electrochemical investigations were focused on the determination of the important nitroaromatic explosive compounds, 2,4,6-trinitrotoluene (TNT) and 2,4,6-trinitroanisole...
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OCENA PRZYDATNOŚCI WIELOWYMIAROWYCH MODELI DYSKRYMINACYJNYCH DO PROGNOZOWANIA UPADŁOŚCI PRZEDSIĘBIORSTW HANDLOWYCH
PublikacjaCelem badań była ocena przydatności użycia modeli opartych na wielowymiarowej analizie dyskryminacyjnej do prognozowania upadłości polskich przedsiębiorstw handlowych oraz próba zwiększenia ich sprawności poprzez zmianę wartości ich punktów granicznych. Badaniu poddano modele: E. I. Altmana „B”, D. Hadasik, A. Hołdy oraz M. Hamrola, B. Czajki i M. Piechockiego. Do oceny modeli wykorzystano iloraz szans oraz macierz klasyfikacji...
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Analiza przestrzenna sprzedaży paliw
PublikacjaZe względu na zmieniające się warunki i niepewność ekonomiczną gospodarowania, przeprowadzane badania dotyczące popytu na paliwa płynne dotyczą głównie zmian popytu w czasie, rzadziej w przestrzeni. Jednak rozwój narzędzi ekonometrycznych, który dokonał się w latach dziewięćdziesiątych, umożliwił nie tylko badania zmian popytu wynikające ze związków przyczynowo-skutkowych zachodzących w czasie, ale również w przestrzeni oraz w...
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Monitoring Salt Water Intrusion During Construction of a Road Tunnel under the Martwa Wisła River in Gdańsk
PublikacjaThe paper presents results of groundwater monitoring carried out during the construction of a road tunnel under the Martwa Wisła river in Gdańsk, Poland. Martwa Wisła is one of the branches of Wisła (Vistula) river, heavily influenced by storm surges and saline water inflow from the Bay of Gdańsk. Increased values of chloride concentration were observed on both sides of the river, in particular on the western side, which was caused...
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Spatial distribution of CO2, O2, CO, NO and temperature within a biowaste composting pile
Dane BadawczeThe dataset contains the color-coded isophlets illustrating the spatial distribution of gas concentrations (CO, CO2, O2 and NO) and the temperature in biowaste composting pile during 6 weeks of process. Four cross sections and two longitudinal cross sections (the left and right sides of the pile) were made using Surfer 10 software (Golden Software,...
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Results of modeling of pharmaceuticals mixtures toxicity with deviation ratio and best-fit functions models using Aliivibrio fischeri bacterium as model organism
Dane BadawczeThe research was concerned with verifying the impact of mixtures of nine pharmaceuticals against a selected organism, i.e., the bacterium Aliivibrio fischeri. A. fisheri is used as a model organism in the monitoring of acute toxicity in environmental and reference samples in Microtox® systems. Tested pharmaceuticals, namely: diclofenac (sodium salt),...
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Surface-dependent biological potential of spherical silver nanoparticles
Dane BadawczeThe growing interest in silver nanoparticles (AgNPs) is largely driven by their significant antimicrobial potential. As carriers of reactive silver ions on a nanoscale, AgNPs are considered excellent candidates for specific antibacterial strategies. Numerous scientific studies have highlighted that AgNPs are broad-spectrum antimicrobials, with their...
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Strahlungslose Übertragung von Elektronenanregungsenergie bei zweidimensionalen lumineszierenden Systemen
PublikacjaAn 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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Hydration of urea and its derivatives - Volumetric and compressibility studies
PublikacjaThe 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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Photolytic and Photocatalytic Recreational Water Treatment
PublikacjaDisinfection 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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Poultry meat freshness assessment based on the biogenic amines index
PublikacjaIn 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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Scalable Measurement System for Multiple Impedance Gas Sensors
PublikacjaAuthor 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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Pracujący w czasie rzeczywistym system detekcji gazów wykorzystujący przenośny komputer Raspberry PI oraz matrycę półprzewodnikowych czujników gazu
PublikacjaThe 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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Aggregation of Rhodamine 6G in titanium dioxide nanolayers and bulk xerogels
PublikacjaNanolayers 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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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
PublikacjaContaminants 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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Real-time working gas recognition system based on the array of semiconductor gas sensors and portable computer Raspberry PI
PublikacjaThe 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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Effect of alkyl sulfate on the phase behavior of microemulsions stabilized with monoacylglycerols
PublikacjaIn 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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The influence of reactions conditions on aggregation of dyes used in biochemistry
PublikacjaSelf-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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Optimization of Saccharification Conditions of Lignocellulosic Biomass under Alkaline Pre-Treatment and Enzymatic Hydrolysis
PublikacjaPre-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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Evaluation of citric acid corrosion inhibition efficiency and passivation kinetics for aluminium alloys in alkaline media by means of dynamic impedance monitoring
PublikacjaA 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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Technical State Assessment of Charge Exchange System of Self-Ignition Engine, Based On the Exhaust Gas Composition Testing
PublikacjaThis 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
PublikacjaThe 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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Zirconia-based mixed potential sensor with Pt electrode prepared by spin-coating of polymeric precursor
PublikacjaMany 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...