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Search results for: POLYBROMINATED DIPHENYL ETHERS (PBDES)MATRIX SOLID-PHASE DISPERSION (MSPD)DUST SAMPLESGAS CHROMATOGRAPHY-ELECTRON IONIZATION-MASS SPECTROMETRY (GC-EIMS)SELECTION OF OPTIMAL CONDITIONS
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Determination of Selected Organic Acids in Animal Farm Water Samples by Ion Chromatography
PublicationLow molecular mass carboxylic acids (LCAs) occur in many environmental compartments due to natural processes and human activity. They are an important group of organic pollutants of waste water that mainly includes, volatile fatty acids, and also dicarboxylic, aromatic, hydroxy- and ketoacids. LCAs are present in the environment at concentrations between 1 to 5000 ppm and different methods have been reported for their determination...
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Validated GC–MS method for determination of bisphenol a and its five analogues in dietary and nutritional supplements
PublicationBisphenol A (BPA) and its analogues showing structural and functional similarity to BPA are commonly applied in various industrial applications and thus are becoming ubiquitous in the environment. At the same time there is increasing scientific evidence that exposure to these chemicals may lead to adverse health effects in human and wildlife. In recent years dietary and nutritional supplements dedicated for athletes have become...
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Preparation, morphology and properties of natural rubber composites filled with untreated short jute fibres
PublicationGreen composites were obtained by incorporation of short jute fibres in natural rubber matrix using a laboratory two-roll mill. The influence of untreated fibre content (1, 2.5, 5, 7.5 and 10 phr) on the mechanical properties, dynamic mechanical properties, swelling properties was examined. The behaviour of prepared green composites under cyclic compression was also investigated. Fibre dispersion in rubber matrix was studied by...
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Rearrangement of azoxybenzocrowns into chromophoric hydroxyazobenzocrowns and the use of hydroxyazobenzocrowns for the synthesis of ionophoric biscrown compounds
PublicationThe Wallach rearrangement was used as a method for preparing p-hydroxyazobenzocrown ethers starting from different azoxybenzocrowns as substrates. Synthesis of a series of p-hydroxyazobenzocrowns under modified conditions and characterization of the obtained products are presented. o-Hydroxyazobenzocrowns were identified among the products of the photochemical rearrangement of azoxybenzocrowns. Novel biscrowns were synthesized...
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Excitation of Non-Wave Modes by Sound of Arbitrary Frequency in a Chemically Reacting Gas
PublicationThe nonlinear phenomena in the field of high intensity sound propagating in a gas with a chemical reaction, are considered. A chemical reaction of A → B type is followed by dispersion and attenuation of sound which may be atypical during irreversible thermodynamic processes under some conditions. The first and second order derivatives of heat produced in the chemical reaction evaluated at the equilibrium temperature, density and...
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DETERMINATION OF SURFACTANTS IN ENVIRONMENTAL SAMPLES - PART I. CATIONIC COMPOUNDS = Oznaczanie Surfaktantów W Próbkach Środowiskowych. Część I. Związki Kationowe
PublicationCompounds from the group of cationic surfactants are widely applied in household, industrial, cleaning, disinfectant, cosmetic and pharmaceutical products as their specific properties (antimicrobial, emulsifying, anticorrosion, softening). After use, cationic surfactants are disposed to wastewater-treatment plants and finally with effluent water to surface waters due to their incomplete degradation. Moreover, they can freely circulate...
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Chemical and biological characterization of Ocimum basilicum L. phenolic extract and essential oil derived through ultrasound and microwave-assisted extraction techniques
PublicationPlant-derived bioactive molecules are increasingly utilized in food processing as natural additives, driven by a growing interest in healthier lifestyles. This trend has spurred industries to reformulate products to meet the demands of health-conscious consumers. This study investigates the phenolic extract and essential oil of O. basilicum L. obtained via ultrasound-assisted extraction and microwave-assisted extraction, respectively. Characterization...
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ALTERNATIVE, DIRECT SYNTHESIS METHOD OF THE CERAMIC SOLID SOLUTIONS BASED ON BaTiO3 THROUGH A HIGH ENERGY BALL MILLING
PublicationPolycrystalline samples BaTiO3 and the solid solutions Ba0.9Sr0.1TiO3, Ba0.9Sr0.1Ti0.9Sn0.1O3, Ba0.9Sr0.1Ti0.8Sn0.2O3 were obtained by means of a mechanochemical treatment based on the high-energy ball milling technique and next a high temperature solid state reaction method. The influence of synthesis condition on microstructural, dielectric and ferroelectric properties of obtained solid solutions were investigated. The structure...
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Determination of impurities in pharmaceutical products using LC-MS
PublicationPharmaceutical products can be contaminated by residues of solvents, reagents (used for the synthesis) or degradation products. Impurities in drug may pose a risk to human health and life, therefore analysis and identification of impurities in pharmaceutical products is veryimportant and inevitable.High performance liquid chromatography coupled with mass spectrometry (MS) is very useful technique for identification impurities in...
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Comparison of an Electronic Nose Based on Ultrafast Gas Chromatography, Comprehensive Two-Dimensional Gas Chromatography, and Sensory Evaluation for an Analysis of Type of Whisky
PublicationWhisky is one of the most popular alcoholic beverages. There are many types of whisky, for example, Scotch, Irish, and American whisky (called bourbon). The whisky market is highly diversified, and, because of this, it is important to have a method which would enable rapid quality evaluation and authentication of the type of whisky. The aim of this work was to compare 3 methods: an electronic nose based on the technology of ultrafast...
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Studies on Silver Ions Releasing Processes and Mechanical Properties of Surface-Modified Titanium Alloy Implants
PublicationDispersed silver nanoparticles (AgNPs) on the surface of titanium alloy (Ti6Al4V) and titanium alloy modified by titania nanotube layer (Ti6Al4V/TNT) substrates were produced by the chemical vapor deposition method (CVD) using a novel precursor of the formula [Ag5(O2CC2F5)5(H2O)3]. The structure and volatile properties of this compound were determined using single crystal X-ray diffractometry, variable temperature IR spectrophotometry...
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Balancing agility and discipline in a research project
PublicationSuccessful software development requires both agility and discipline. Optimal selection of methods, however, is not an easy task. The problem becomes even more difficult for long lasting projects. Appropriate selection of methods involving skillful introduction and abandonment of certain practices in time makes the whole process dynamic. The paper presents in this context a research project which was realized in a few iterations....
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The Optimal Location of Ground-Based GNSS Augmentation Transceivers
PublicationModern Global Navigation Satellite Systems (GNSS) allow for positioning with accuracies ranging from tens of meters to single millimeters depending on user requirements and available equipment. A major disadvantage of these systems is their unavailability or limited availability when the sky is obstructed. One solution is to use additional range measurements from ground-based nodes located in the vicinity of the receiver. The highest...
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THE COMPOSITION MODULATION EFFECT IN GaInPAs SOLID SOLUTIONS AS A MANIFESTATION OF ENERGY RESONANCE AFTER MATERIAL'S SPINODAL DECOMPOSITION
PublicationThe Cahn-Hilliard model concepts are extended to describe the spinodal decomposition of Ga$_x$In$_{1-x}$P$_y$As$_{1-y}$ solid solutions grown on the InP substrate. The energy of elastic deformation of the thin layer of a solid solution was calculated on the assumption of its coherent conjugation with the massive InP substrate. The excess energy of component mixing in the solid phase was modeled in accordance with the simple solution...
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The XRD diffraction patterns of Ce0.8La0.2O2/Ni prepared using soft template method and impregnation
Open Research DataThe dataset includes XRD patterns of Ce0.8La0.2O2-s nanopowders (nanoparticles,nanocatalyst) prepared using soft template method and further impregnated with 10wt.%Ni using aqueous nitrate solution.
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Prediction of flow boiling heat transfer coefficient for carbon dioxide in minichannels and conventional channels
PublicationIn the paper presented are the results of calculations using authors own model to predict heat transfer coefficient during flow boiling of carbon dioxide. The experimental data from various resea rches were collected. Calculations were conducted for a full range of quality variation and a wide range of mass velocity. The aim of the study was to test the sensitivity of the in-house model. The results show the importance of taking into...
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Influence of processing conditions on crystal structure of BiNbO 4 ceramics
PublicationBismuth niobate (BiNbO4) has attracted attention as a low-fired ceramics with promising microwave application potential. It belongs to the bismutocolumbite oxides with similarly to scheelite-like stibiotantalite structure (SbTaO4) A3+B5+O4. Aim of the present research was to fabricate BiNbO4 ceramics by solid state reaction route from the mixture of simple oxides viz. Bi2O3, and Nb2O5, and study its phase composition as well as...
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Nanosorbents as Materials for Extraction Processes of Environmental Contaminants and Others
PublicationThe aim of this work focuses on the application of nanomaterials (NMs) in different sorp- tive extraction techniques for the analysis of organic contaminants from environmental samples of distinct matrix compositions. Without any doubt, the integration of specific NMs such as carbona- ceous nanomaterials, magnetic nanoparticles (MNPs), metal–organic frameworks (MOFs), silica na- noparticles, and ion-imprinted NPs with so lid-phase...
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Novel decahedral TiO2 photocatalysts modified with Ru or Rh NPs: Insight into the mechanism
PublicationNovel decahedral TiO2 modified with Ru or Rh NPs were successfully synthesized by hydrothermal method. The effect of metal type as well as amount of noble metal precursor (0.05, 0.1, 0.2, 0.3 and 0.5 wt.%) on the photocatalytic activity were investigated. Decahedral TiO2 decorated by Ru and Rh nanoparticles was prepared by photodeposition method, whereas Rh doped TiO2 was obtained by onestep hydrothermal method with introduction...
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Electron energy-loss spectroscopy of excited states of the diazine molecules: Pyridazine
PublicationExcitation of the valence electronic states of the pyridazine molecules in the gas phase have been studied using the technique of electron energy-loss spectroscopy. Varying the electron scattering conditions, the residual electron energy and scattering angle, enabled the optically-allowed and -forbidden excitations to be differentiated. The measured energy-loss spectra enabled the vertical excitation energies of the observed states...
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Characterization of Highly Filled Glass Fiber/Carbon Fiber Polyurethane Composites with the Addition of Bio-Polyol Obtained through Biomass Liquefaction
PublicationThis work aims to investigate the process of obtaining highly filled glass and carbon fiber composites. Composites were manufactured using previously obtained cellulose derived polyol, polymeric methylene diphenyl diisocyanate (pMDI). As a catalyst, dibutyltin dilaurate 95% and Dabco® 33-LV were used. It was found that the addition of carbon and glass fibers into the polymer matrix causes an increase in the mechanical properties...
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Badania stabilności chemicznej kompozytowego elektrolitu 3-YSZ-Al2O3 w stosunku do materiałów elektrodowych do zastosowania w średniotemperaturowych ogniwach paliwowych
PublicationJednym z podstawowych wymogów stawianych mate- riałom na elektrolity do średniotemperaturowych ogniw paliwowych IT-SOFC (ang. intermediate-temperature solid oxide fuel cells) jest ich kompatybilność chemiczna z elektrodami w temperaturach zarówno eksploatacji, jak i wytwarzania ogniw. W celu sprawdzenia, czy badany w pracy kompozytowy elektrolit o osnowie z częściowo stabilizowanego ditlenku cyrkonu i z wtrąceniami tlenku glinu...
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Application of a Gas Sensor Array to Effectiveness Monitoring of Air Contaminated with Toluene Vapors Absorption Process
PublicationThis article demonstrates the application of a gas sensor array to monitor the effectiveness of the absorption process of air stream purification from odorous compounds (toluene vapors). A self-constructed matrix consisting of five commercially available gas sensors was used. Multiple linear regression (MLR) was selected as the statistical technique used to calibrate the matrice. Gas chromatography coupled with a flame ionization...
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Comprehensive stabilization of all streams of solid residues formed during sewage sludge thermal treatment – Case study
PublicationModern wastewater treatment plants are currently struggling with the problem of processing and ecological management of sewage sludge. Thermal utilization is a frequently used practice of excess sludge utilization especially in large wastewater treatment plants, which seems to be a quite promising concept. However, during thermal treatment, fractions of ashes and dusts are generated. Such wastes, especially the dust fraction, can...
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Ewa Wagner-Wysiecka dr hab. inż.
PeopleEwa Wagner-Wysiecka is a graduate of the Faculty of Chemistry at Gdańsk University of Technology (specializing in Chemical Technology, with a focus on Inorganic Technology and a sub-specialty in Technical and Industrial Analytics). She completed her master's thesis, entitled "Identification of Contaminants in Pharmacopoeial Sulfaquinoxaline," under the supervision of Professor Jan F. Biernat. After completing her master's degree...
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Simultaneous opto-electrochemical monitoring of carbamazepine and its electro-oxidation by-products in wastewater
PublicationThe growing human impact on aquatic environments, due to the extensive use of pharmaceuticals and the release of persistent pollutants, makes it necessary to implement new widespread methods for the characterisation and quantification of such contaminants and relative degradation products. Carbamazepine, 5H-dibenzo[b,f]azepine-5-carboxamide, (CBZ) is a widely used anti-epileptic drug, characterised by its limited removal by conventional...
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Electrochemical simulation of enzymatic transformations studied for the selected antitumor acridine derivatives
PublicationThe elucidation of the metabolic pathways and the biotransformation mechanisms of potential drugs is a crucial point in drug development. It allows to know the activation routes of the new biologically active compounds, especially in respect to their possible toxicity. Generally, in vivo or in vitro experiments with liver microsomes or hepatocytes are performed. However, these testing schemes are tedious, time consuming and of...
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Detection of some volatile degradation products released during photoexposition of ranitidine in a solid state
PublicationRanitidine (RAN) is on top of the list of prescribed drugs, due to its popularity as a selective H2-receptor antagonist, which efficiently decreases the amount of acid produced in the stomach. RAN is not stable both in a solid state and in a solution, which creates manufacturing problems, requires appropriate storage conditions, and results in a short drug shelf-life. The aim of this work was to study the emission of volatile...
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Influence of selected submicron inorganic particles on mechanical and thermo-mechanical properties of unsaturated polyester/glass composites
PublicationIn this paper, the influence of different submicron-scaled particles (zinc oxide, titanium dioxide, or silica) on mechanical and thermo-mechanical properties of unsaturated polyester matrix composites reinforced with glass fabric was investigated. Surface morphology of obtained composites was also examined. At first inorganic particles were mechanically dispersed into unsaturated polyester resin system as per the calculated weight...
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Poultry (chicken) manure biochar - Scanning Electrone Microscope (SEM) images
Open Research DataThis dataset contains scanning electron microscope images of poultry (chicken) manure biochars produced at different temperature conditions (400, 500, and 600 degrees Celsius). Imaging was carried out with an FEI Quanta FEG250 scanning electron microscope equipped with a SE-ETD detector (secondary electron - Everhart-Thornley detector) and a 20 kV accelerating...
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Application of ultrasound-assisted solvent extraction of porous membrane packed liquid samples for polyphenols determination in wine samples
PublicationPolyphenols play a crucial role in a proper human health maintenance as well as their presence very often correspond to the quality assessment of producs like wine. Thus, their monitoring is of high interest. However, as they occur in a complex matrices their extraction is very often necessary prior the analysis. Herein, a new ultrasound-assisted solvent extraction of porous membrane packed liquid sample technique has been optimized...
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Occurrence and Levels of Biogenic Amines in Beers Produced by Different Methods
PublicationThe concentration of biogenic amines (BAs) in beer depends, among other factors, on the activity of microorganisms, in particular lactic acid bacteria. In this work an analytical method based on derivatization with tosyl chloride and high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was used to determine 17 BAs in samples of commercially available beers, and to monitor the changes in concentration of...
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Application of Impedance Spectroscopy for Bi1−xNdxFeO3 Ceramics Characterization
PublicationIn the present paper the synthesis conditions for fabrication of Bi1−xNdxFeO3 ceramics are reported. The single phase polycrystalline samples of Bi1−xNdxFeO3 were prepared by standard solid state reaction method from the mixture of oxides viz.: Bi2O3, Fe2O3 and Nd2O3. The samples were characterized by impedance spectroscopy in the frequency range 10Hz – 1MHz at room temperature.
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New methodology for determination cationic surfactants in liquid environmental samples
PublicationBecause of their specific physical and chemical properties (e.g. amphiphilicity, solubility in polar and nonpolar liquids, ability to form micelles, adsorption at phase boundaries, low toxicity) surfactants (surface-active compounds) are widely applied in industry and in the household. As their applications are on a very large scale, it has become necessary to acquire a more detailed understanding of their environmental fate. Mainly,...
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Composition and antimicrobial activity of fatty acids detected in the hygroscopic secretion collected from the secretory setae of larvae of the biting midge Forcipomyia nigra (Diptera: Ceratopogonidae)
PublicationThe hygroscopic secretion produced by the secretory setae of terrestrial larvae of the biting midge Forcipomyia nigra (Winnertz) was analysed using gas chromatography coupled with mass spectrometry (GC-MS). The viscous secretion is stored at the top of each seta and absorbs water from moist air. GC-MS analyses (four independent tests) showed that the secretion contained 12 free fatty acids, the most abundant of which were oleic...
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Determination of Odor Air Quality Index (OAQII) Using Gas Sensor Matrix
PublicationThis article presents a new way to determine odor nuisance based on the proposed odor air quality index (OAQII), using an instrumental method. This indicator relates the most important odor features, such as intensity, hedonic tone and odor concentration. The research was conducted at the compost screening yard of the municipal treatment plant in Central Poland, on which a self-constructed gas sensor array was placed. It consisted...
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Analysis of pesticide residue in fruits and vegetables using analytical analytical protocol based on application of QuEChERS technique and GC-ECD system
PublicationQuEChERS sample preparation method was used for the determination of 10 pesticides and their metabolites in fruits (apple, grape) and vegetables (tomato, paprika), coupled to gas chromatography with electron capture detector (GC-ECD). The experimental parameters including amount of the sample, types of solvents, extraction time and types of sorbent at the purification stage were optimized. The GC-ECD method was validated in terms...
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Determination of benzodiazepines and Z-hypnotic drugs in whole blood samples by GC–MS/MS: Method development, validation and application
PublicationBenzodiazepines (BZDs) and Z-drugs are widely used as anxiolytics, sedative hypnotics, anticonvulsants and muscle relaxants. “Designer benzodiazepines” (DBZDs) are a new psychoactive substance class consisting of benzodiazepine derivatives that are not allowed for medical use and are known for being used recreationally. From a toxicologist standpoint, the huge number of such substances implicate a necessity for developing fast...
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Bezpośrednia analiza próbek z wykorzystaniem techniki spektrometrii mas. Cz. II. Technika PTR – MS – ciekawe rozwiązanie metodyczne w zakresie spektrometrii mas
PublicationTechnika spektrometrii mas stanowi niezwykle istotne narzędzie badawcze, umożliwiające uzyskanie wielu cennych informacji, dotyczących składu chemicznego wielu próbek rzeczywistych pochodzenia biologicznego, farmaceutycznego i spożywczego. Spektrometr mas zazwyczaj pełni role detektora w przypadku stosowania połączenia z urządzeniami chromatograficznymi (GC, LC). Dzięki zastosowaniu pewnych modyfikacji aparaturowych i metodycznych,...
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Corrosion degradation monitoring of ship stiffened plates using guided wave phase velocity and constrained convex optimization method
PublicationThe study presents an experimental investigation on the corrosion degradation level assessment using nondestructive wave-based methods. The degradation level of ship structural elements has been assessed in two different ways. The first one is based on the spectral decomposition and zero-crossing incorporated reconstruction of the dispersion curve approach of the antisymmetric Lamb wave mode and the best matching of the theoretical...
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Obrony prac doktorskich na Wydziale Chemicznym
EventsDn. 22.04.2022 r. o godz. 10.15 w Audytorium 1.4 Wydziału Chemicznego PG (budynek nr 5) odbędzie się w trybie hybrydowym publiczna obrona pracy doktorskiej mgr inż. Katarzyny Nalazek-Rudnickiej.
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Anti-plane surface waves in media with surface structure: Discrete vs. continuum model
PublicationWe present a comparison of the dispersion relations derived for anti-plane surface waves using the two distinct approaches of the surface elasticity vis-a-vis the lattice dynamics. We consider an elastic half-space with surface stresses described within the Gurtin–Murdoch model, and present a formulation of its discrete counterpart that is a square lattice half-plane with surface row of particles having mass and elastic bonds different...
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Flow Maps and Flow Patterns of R1233zd(E) in a Circular Minichannel at Low, Medium and High Values of Saturation Pressure
PublicationThere is a gap in knowledge regarding the flow pattern of low-boiling working fluids in the range of high saturation temperatures (above 120°C) and medium and high reduced pressures (0.5-0.9). Data are present in the literature for similar values of reduced pressures, but for lower values of saturation temperature. This is due to the existing refrigeration applications of these working fluids. At high values of reduced pressure,...
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Yields and Time-of-Flight Spectra of Neutral High-Rydberg Fragments at the K Edges of the CO2 Molecule
PublicationWe have studied the production of neutral fragments in high-Rydberg (HR) states at the C 1s and O 1s edges of the CO2 molecule by performing two kinds of experiments. First, the yields of neutral HR fragments were measured indirectly by ionizing such fragments in a static electric field and by collecting resulting singly charged positive ions as a function of the photon energy. Such measurements reveal not only excitations below...
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Analysis of volatile fraction selected hybrid fruits using chromatographic techniques
PublicationAt present, "healthy eating" is gaining in popularity. Many people associate this term with eating plenty of vegetables and fruits. The basic elements influencing the selection of fruit are their appearance and smell. Of course, their origin and impact on human health are also very important. In recent years, exotic fruits have become increasingly accessible, making them gaining popularity, even among Poles. You can also meet plants...
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Ionosphere variability I: Advances in observational, monitoring and detection capabilities
PublicationThe paper aims to review recent advances regarding the observational and monitoring capabilities of the ionization conditions in the Earth's upper atmosphere. The analysis spans both ground and space-based experiments, seeking for new installations and/or missions, new or upgraded instrumentation and/or observational network establishments as means for advancing current understanding and prediction ability of the ionosphere variability....
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Sulfur compounds: Gas chromatography
PublicationSulfur compounds, due to their properties, are responsible for the damage of our environment. For this reason sulfur containing compounds are of constant concern in many fields. Gas chromatography (GC), due to combination of separation capability and sensitive detection is a prime technique for the analysis of thes compounds in various matrices. The chapter rewies general problems of the determination of these compounds by GC and...
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A model of liquid film breakdown formed due to impingement of a two-phase jet on a horizontal surface
PublicationThe present work aims to provide an explanation to the phenomenon of breakdown of the thin liquid film created by impinging two-phase, liquid-gas jet. Existing in the literature models describe merely thebreakdown of single phase liquid films. The model presented here is based on examination of mass and energy equations under the applied criterion of the minimum of total energy. That allows to determinethe minimum thickness of...
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SEM micrographs of ammonium vanadate nanocrystals
Open Research DataThe DataSet contains the electron microscopy (SEM) micrographs of ammonium vanadate nanobelts obtained by the hydrothermal method with different conditions. The results show that the morphology of samples dependent on reaction conditions.
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Effect of crystallization process at cryogenic conditions on the functional properties of the SUPERSTON alloy used in production the ship's propellers
PublicationThe purpose of this paper is to show results of laser treatment at cryogenic conditions of the SUPERSTON alloy used for ship's propellers. That modification process ought to bring beneficial changes of microstructure and residual stresses in the surface layer. During the laser remelting at cryogenic conditions the microstructure changes significantly. This is related to synergistic effects of the solidification rate, phase transformations...