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Improvement of Task Management with Process Models in Small and Medium Software Companies
PublikacjaSmall and medium software companies exhibit many special features that give reason for a dedicated approach to process improvement. They often cannot afford implementing maturity models or quality standards both in terms of time and money. Instead, they expect simpler solutions that can allow to run projects in more systematic and repeatable way, increase quality and knowledge management. In this paper, we present a method focused...
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Classification and fingerprinting of kiwi and pomelo fruits by multivariate analysis of chromatographic and spectroscopic data
PublikacjaThe fingerprinting capacity of two analytical techniques, HPLC and UV-Vis spectroscopy in the case of fruits samples (kiwi and pomelo) has been investigated. The multivariate exploratory techniques were used for sample discrimination according to the fruit species and subspecies. The combination of principal component analysis with linear discriminant analysis is opening new directions in the fingerprinting analysis. The classifications...
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Chemical Quality of Bottled Waters: A Review
PublikacjaBottled water has become very popular for quenching thirst and as a dietary (mineral) supplement. Theplethora of natural mineral waters precludes any unequivocal system of classification, which makes it difficult for theconsumer to choose a water with properties that suits him/her exactly. The ever-increasing popularity of bottled watersmeans that it is of the utmost importance to determine not only their mineral content, but above...
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The enantiomeric determination of chloro-precursors of methamphetamine
PublikacjaImpurity profiling and classification of seized methamphetamine may supply valuable information with respect to the conditions and the chemicals used in the illicit methamphetamine manufacture and may provide information on the original source of the sample. Determination of the stereochemical makeup of forensic samples is important as well for the same reasons. Laboratories in many places are engaged in clandestine manufacture...
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On degradation of glass/polyester laminate immersed in water
PublikacjaMechanical behaviour was compared for glass/ polyester laminates manufactured in the boatbuilding plant using three methods: hand lay-up, vacuum bagging, infusion. Specimens were tested in dry condition and following accelerated water immersion test (70°C- corresponding to the exposure of 30 years at 19°C). In three point bending test 40-50% reduction in laminate strength was observed due to water immersion. The highest degradation...
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The use of bioassays in the analysis of environmental samples
PublikacjaToxicological tests are increasingly used as effective tool to complement the information obtained during the environmental monitoring. Moreover bioassays provide basic knowledge about the health effects of exposure to harmful factors associated with the environment. Toxicity tests might be a source of information about the content of pollutants in the sample, and the possibility of their interactions. They can be considered as...
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Application of additional factors supporting the microextraction process
PublikacjaDue to the fact that green analytical chemistry is of high importance, the past two decades have witnessed a rapid growth in the sample preparation area with special emphasis on simplification, miniaturization and automation of extraction procedures. In addition, to accelerate the extraction processes and to improve the separation of analytes, several enhanced parameters are applied. These factors include, ultrasounds, microwaves,...
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Diamond-Phase (Sp3-C) Rich Boron-Doped Carbon Nanowalls (Sp2-C): A Physico-Chemical And Electrochemical Properties
PublikacjaThe growth of B-CNW with different boron doping levels controlled by the [B]/[C] ratio in plasma, and the influence of boron on the obtained material’s structure, surface morphology, electrical properties and electrochemical parameters, such as -ΔE and k°, were investigated. The fabricated boron-doped carbon nanowalls exhibit activity towards ferricyanide redox couple, reaching the peak separation value of only 85 mV. The flatband...
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Thermal degradation assessment of canola and olive oil using ultra-fast gas chromatography coupled with chemometrics
PublikacjaOil blending is often used to enhance the properties of vegetable oils. The admixture of a more thermally stable oil makes the resulting blend more suitable for use in frying. A new method of quality assessment of vegetable oils used in frying is presented in this paper. In this method, ultra-fast gas chromatography coupled with flame ionization detector and chemometrics is employed. Principal component analysis was used for data...
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Analytical procedures for quality control of pharmaceuticals in terms of residual solvents content: Challenges and recent developments
PublikacjaResidual solvents play an important role in the synthesis of drugs and in product formulations. In addition, they pose a serious problem, that is toxicity, as many of them exhibit toxic or environmentally hazardous properties. Therefore, constant monitoring of quality control is needed. In this study, we present an overview of regulatory and general methods described by various pharmacopoeias. Then, the most commonly used methodologies...
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Superconductivity and itinerant ferromagnetism of Y9Co7 probed by ac susceptibility
PublikacjaThe ac magnetic susceptibility of a single crystal sample of the compound Y9Co7 has been measured in applied dc fields ranging from 0–6.7 kOe by utilizing a tunnel diode resonator circuit. In agreement with previous measurements on this material, a superconducting transition has been observed to occur at TSC ≈ 2.5 K. A broad maximum has been observed in the zero field susceptibility measurements from 2.5 K < T < 8 K and its behavior...
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POSITIVE PSYCHOLOGICAL CAPITAL ENHANCES THRIVING IN THE MULTICULTURAL WORK ENVIRONMENT OF MULTINATIONAL CORPORATIONS
PublikacjaThe aim of the paper is to examine positive psychological capital (PsyCap) as well as individual factors in the relationship with thriving in the multicultural work environment of multinational corporations (MNCs). We conducted a quantitative study on the sample of 127 individuals from subsidiaries of various MNCs located in Poland and involved in intercultural interactions. The results of cross-sectional study show that employees...
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Problems and chellenges to determine pesticide residues in bumblebees
PublikacjaBumblebees play an important role in t he pollination process of many crops and flowers. Therefore, taking action to protect and assess the impact of p esticides on these insects is fully justi fied. Pesticides may cause mortality and also sub-lethal effects that are not always directly visible. Bumblebees, like honeybees, can be used as indicators for environmental monitoring contamination. Two approaches are mainly used for the...
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Understainding solid-phase microextraction: key factors influencing the extraction process and trends in improving the technique
PublikacjaAnalytical chemists are faced with the daunting challenges of accurately monitoring the state of the environment and the processes taking place in it and of determining an enormous range of analytes often present in trace and ultratrace amounts in sample matrixes with complex or variable compositions. Further challenges are presented by the need to introduce new methodologies into current analytical practice and equipment to comply...
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Elimination of excretion of ibuprofen and its metabolites in horses
PublikacjaAnalytical procedure based on application of gas chromatography-mass spectrometry (GC-MS) at the step of detection, identification and quantitation of ibuprofen (IBU) and detection of its metabolites – 1-hydroxyibuprofen (1-OH IBU) and carboxyibuprofen (CBX IBU) in horse urine by selected ion monitoring mode after sample preparation covering extraction at pH 3-4 and methylation has been used. The ions at m/z 161, 220 (methylated...
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Structure and thermoelectric properties of Bi–Te alloys obtained by novel method of oxide substrates reduction
PublikacjaA novel method of thermoelectric materials fabrication has been developed. Oxide reagents have been melted at high temperature in air, quenched, milled to powder and reduced in hydrogen to form Bi–Te alloys. Structural and thermoelectric properties of samples have been investigated depending on initial composition and temperature of reduction process. Sample 25Bi2O3–75TeO2 reduced at 340 °C for 10 h has been found to be a p-type...
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Exploring efficiency differentials between Italian and Polish universities, 2001-2011
PublikacjaIn this study, data envelopment analysis (DEA) is used to evaluate the relative efficiency of a sample of 54 Italian and 30 Polish state universities over the period 2001–11. The investigation was conducted in two steps. Unbiased DEA efficiency scores were first estimated and then regressed on external variables to quantitatively assess the direction and size of the impact of potential determinants. The analysis reveals a strong...
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Ag/Pt-modified TiO2 nanoparticles for toluene photooxidation in the gas phase
PublikacjaAg/Pt-modified TiO2nanocomposites were synthesized using the sol–gel method. The effect of metal typeand amount as well as synthesis route on the photocatalytic activity in reaction of toluene removal, usedas a model volatile organic compound, was investigated. Toluene, at the concentration of about 200 ppm,was irradiated over modified TiO2using light-emitting diodes (LEDs, max= 415 nm). The results showedthat toluene could be...
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Problems of modelling toxic compounds emitted by a marine internal combustion engine in unsteady states
PublikacjaContemporary engine tests are performed based on the theory of experiment. The available versions of programmes used for analysing experimental data make frequent use of the multiple regression model, which enables examining effects and interactions between input model parameters and a single output variable. The use of multi-equation models provides more freedom in analysing the measured results, as those models enable simultaneous...
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Application of magnetic nanoparticles for magnetic solid-phase extraction in preparing biological, environmental and food samples
PublikacjaThe need to obtain meaningful results as the basis for determining the content of trace amounts of analytes has become the driving force behind the development of modern analytical techniques, including sample-preparation techniques, such as solid-phase extraction (SPE). Recently, great interest was aroused in the use of magnetic nanoparticles (MNPs) in SPE. These materials exhibit high selectivity, and, in small amounts, can provide...
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Methane formation over TiO2–based photocatalysts: reaction pathways
PublikacjaThe effects of organic impurities adsorbed or incorporated into semiconductors structure on the photocatalytic products are noteworthy. For this purpose, the as-prepared Ag, Au and Pdmodified TiO2 samples were exposed to UV-vis irradiation in various gas atmospheres (CO2, N2, 600 ppm CO2 in N2, and 13CO2) in order to clarify the route of CH4 formation in the process of photocatalytic CO2 reduction. In the presented research it...
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Exploring universities' efficiency differentials between countries in a multi-year perspective: an application of bootstrap DEA and Malmquist index to Italy and Poland, 2001-2011
PublikacjaThis study employs data envelopment analysis (DEA) to evaluate relative efficiency of a sample of 54 Italian and 30 Polish public universities for the period between 2001 and 2011. The examination is conducted in two steps: first unbiased DEA efficiency scores are estimated and then are regressed on external variables to quantitatively asses the direction and magnitude of the impact of potential determinants. The analysis shows...
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Enhanced Electrochemical Performance of MnCo1.5Fe0.5O4Spinel for Oxygen Evolution Reaction through Heat Treatment
PublikacjaMnCo1.5Fe0.5O4 spinel oxide was synthesized using the sol−gel technique, followed by heat treatment at various temperatures (400, 600, 800, and 1000 °C). The prepared materials were examined as anode electrocatalysts for watersplitting systems in alkaline environments. Solid-state characterization methods, such as powder X-ray diffraction and X-ray absorption spectroscopy (XAS), were used to analyze the materials’ crystallographic...
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Role of research and development in internationalization of high-tech firms: Empirical results from Poland
PublikacjaThe article focuses on the significance of research and development (R&D) in driving the internationalization of Polish high-tech firms. R&D is essential for businesses to remain competitive and adapt their products to the specific requirements of different markets. The study aims to investigate the relationship between R&D and the internationalization process of high-tech firms based in Poland, with a focus on the innovation context....
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Experimental study and numerical simulation of the dynamic penetration into dry clay
PublikacjaTests of dry clay were carried out in a uniaxial stress state using the experimental setup which implements the split Hopkinson pressure bar method. Based on the results of these experiments, the compressive strength of clay was determined as an important element of S.S. Grigoryan’s model of the soil medium. In addition, the parameters of this model are determined from the results of experiments using the modified Kolsky method...
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Using Synchronously Registered Biosignals Dataset for Teaching Basics of Medical Data Analysis – Case Study
PublikacjaMedical data analysis and processing strongly relies on the data quality itself. The correct data registration allows many unnecessary steps in data processing to be avoided. Moreover, it takes a certain amount of experience to acquire data that can produce replicable results. Because consistency is crucial in the teaching process, students have access to pre-recorded real data without the necessity of using additional equipment...
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Wide-field magnetometry using nitrogen-vacancy color centers with randomly oriented micro-diamonds
PublikacjaMagnetometry with nitrogen-vacancy (NV) color centers in diamond has gained significant interest among researchers in recent years. Absolute knowledge of the three-dimensional orientation of the magnetic field is necessary for many applications. Conventional magnetometry measurements are usually performed with NV ensembles in a bulk diamond with a thin NV layer or a scanning probe in the form of a diamond tip, which requires a...
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Don't forget the dark side of green transformation
PublikacjaDesign/methodology/approach – The study is a continuation of the research by Durst and Zieba (2019) related to knowledge risks and their potential outcomes. This present study makes an update on the literature on knowledge risks and green transformation and describes knowledge risks that can be faced in this process. Originality/value – The paper offers new insights for researchers dealing with the topic of knowledge risks in...
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Development of Microstructured Carbon Coatings by Substrate-Catalytic CVD
PublikacjaCarbon nanostructured films were synthesized by chemical vapor deposition (CVD) on H18 stainless steel (AISI 440C) sheets with an H2/CH4/N2 gas mixture at various substrate temperatures. During the synthesis, the iron and chromium oxide layer was formed between the steel and carbonaceous layer. The carbon films exhibited wall-like and spherical morphologies and structures, as characterized by scanning electron microscopy and Raman...
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Highly Oriented Zirconium Nitride and Oxynitride Coatings Deposited via High‐Power Impulse Magnetron Sputtering: Crystal‐Facet‐Driven Corrosion Behavior in Domestic Wastewater
PublikacjaHerein, highly crystalline ZrxNy and ZrxNyOz coatings are achieved by the deposition via high‐power impulse magnetron sputtering. Various N2 and N2/O2 gas mixtures with argon are investigated. The chemical composition and, as a result, mechanical properties of the deposited layer can be tailored along with morphological and crystallographic structural changes. The corrosion resistance behavior is studied by potentiodynamic measurements...
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Relative Productivity, Country Size and Export Diversification
PublikacjaThis paper analyses the effects of productivity and country size on the extent of trade structure diversification. Using a testable version of the Ricardian model, we show that relative export variety is an outcome of two forces: a relative productivity change (technological progress) and a relative country size change (labour force growth). The model predictions are validated empirically using product-level trade data for a sample...
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Synthesis of Phosphonated Carbon Nanotubes: New Insight into Carbon Nanotubes Functionalization
PublikacjaCarbon nanotubes were successfully functionalized for the first time in a free radical phosphonylation reaction. Three synthetic protocols were proposed. Carbon nanotubes and diethylphosphite reacted in the presence of known radical initiator, such as azobisisobutyronitrile, single electron oxidant—Mn(OAc)3, or under UV radiation. The functionalized material was fully characterized by means of spectroscopic methods, together with...
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Lamb wave-based monitoring of shear failure of an adhesive lap joint
PublikacjaThe paper presents a study on the elastic wave propagation in adhesive joints of steel plates subjected to tensile loading. A single lap joint was chosen for analysis because of its simplicity and plurality of applications. Experimental investigations consisted of the uniaxial extension of prepared specimens. Force and displacement values were recorded by a testing machine. Simultaneously, guided Lamb waves were excited and signals...
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Detection of debonding in adhesive joints using Lamb wave propagation
PublikacjaAdhesively bonded joints are widely used in many branches of industry. Mechanical degradation of this type of connections does not have significant symptoms that can be noticed during visual assessment, so non-destructive testing becomes a very important issue. The paper deals with experimental investigations of adhesively bonded steel plates with different defects. Five samples (an intact one and four with damages in the form...
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Application of the Barkhausen effect probe with adjustable m agnetic field direction for stress state determination in the P91 ste el pipe
PublikacjaThe paper presents the results of application of a novel Barkhausen effect (BE) probe with adjustable magnetizing field direction for the stress level evaluation in ferromagnetic materials. The investigated sample was in a form of a pipe, made of P91 steel that was anisotropic due to the production process. The measurements were performed before and after welding, revealing the influence of welding process on the residual stress...
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Temperature Measurements at Tyre Tread Rubber on Sandpaper Oscillatory Sliding Contacts Using Acicular Grindable Thermocouples
PublikacjaThe tribological performance of tyre–road contacts depends crucially on the contact temperature. This study investigates the reliability and accuracy of acicular grindable thermocouples possessing an original needle-shaped wearable part as applied to measuring temperature at the oscillatory sliding contact between a rubber tyre tread sample and a sandpaper. A linear oscillatory tribometer is used to imitate the sliding phase of...
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Architektura przyjazna seniorom w Polsce XXI wieku. Kształtowanie przestrzeni zamieszkania, pracy i rozrywki
PublikacjaPolska, podobnie jak wiele innych krajów, zmaga się obecnie z procesem starzenia społeczeństwa, który w najbliższych latach będzie przybierał na sile. Dlatego bardzo istotne jest, aby już teraz rozpocząć proces przystosowywania miast do zmieniającej się struktury społecznej, tak aby w przyszłości mogły być one miejscem, w którym ludzie starsi będą mogli swobodnie i bezpiecznie mieszkać oraz funkcjonować. W realiach polskich można...
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Analizy ilości i jakości odpływu wód deszczowych i roztopowych z kontrolowanej zlewni zurbanizowanej
PublikacjaIstotnym problemem Gdańska staje się bezpieczeństwo ekologiczne związane ze spływami miejskimi odprowadzanymi bezpośrednio do wód powierzchniowych, często akwenów użyteczności publicznej. W latach 2011÷2013, Katedra Hydrotechniki Wydziału Inżynierii Lądowej i Środowiska Politechniki Gdańskiej, we współpracy z Wojewódzkim Funduszem Ochrony Środowiska i Gospodarki Wodnej w Gdańsku oraz Gdańskimi Melioracjami, podjęła się wdrożenia...
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Stopniowa chromatografia cienkowarstwowa w normalnych układach faz (NP-TLC), jako technika rozdzielania i oceny składu grupowego frakcji asfaltenowych z utleniania pozostałości próżniowej ropy naftowej
PublikacjaW pracy opisano wyniki badań nad opracowaniem metodyki oceny składu grupowego i czystości frakcji asfaltenowych techniką chromatografii cienkowarstwowej w normalnych układach faz (NP-TLC). Skupiono się na doborze takich parametrów/warunków rozdzielania, jak stężenie i masa próbki, a także skład i kolejność eluentów stosowanych podczas rozwijania chromatogramów TLC. Zastosowana trój-stopniowa metodyka polega na nałożeniu 5 µL frakcji...
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Youth Civic Participation in the South Baltic Region. Example of Lithuania, Poland and Sweden
PublikacjaThe aim of this study was to show youth civic participation as a social inclusion element in the Southern Baltic region in need of reinforcement, based on the examples of selected municipalities from Lithuania, Poland and Sweden. The authors focused on the diagnosis of key elements of youth civic engagement at local and cross-border level, taking into account the context of national youth policies and the European Union policy....
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Love your mistakes!—they help you adapt to change. How do knowledge, collaboration and learning cultures foster organizational intelligence?
PublikacjaPurpose: The study aims to determine how the acceptance of mistakes is related to adaptability to change in a broad organizational context. Therefore it explores how knowledge, collaboration, and learning culture (including “acceptance of mistakes”) might help organizations overcome their resistance to change. Methodology: The study uses two sample groups: students aged 18–24 (330 cases) and employees aged >24 (326 cases) who work...
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Rapid and simple multi-analyte LC–MS/MS method for the determination of benzodiazepines and Z-hypnotic drugs in blood samples: Development, validation and application based on three years of toxicological analyses
PublikacjaBenzodiazepines (BZDs) and Z-drugs have been particularly important treatments for sleeping and anxiety disorders for many years. However, recently, a number of new benzodiazepines (named designer benzodiazepines, DBZDs) were synthesised, but some of them have never been used in the clinic; they reached the black drug market as new psychoactive substances and are used for recreational purposes. The abuse of these substances has...
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Sintering Parameter Investigation for Bimetallic Stainless Steel 316L/Inconel 718 Composite Printed by Dual-Nozzle Fused Deposition Modeling
PublikacjaFused deposition modeling (FDM) nowadays offers promising future applications for fabricating not only thermoplastic-based polymers but also composite PLA/Metal alloy materials, this capability bridges the need for metallic components in complex manufacturing processes. The research is to explore the manufacturability of multi-metal parts by printing green bodies of PLA/multi-metal objects, carrying these objects to the debinding...
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Fracture in composite/aluminium joints of variable adhesive properties
PublikacjaA strain gauge technique recently developed with the wedge test, for estimating crack length and, thus, the fracture energy of structural adhesive bonding, has been employed on a system in which one adherend had two types of surface treatment. Simple polishing and polishing with subsequent sandblasting were the treatments used, with a distinct straight line, perpendicular to the sample edges, separating the two. Despite the clear-cut...
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Determination of Butyltin Species in Sea Water Samples Using Solid Phase Extraction Followed by Liquid Chromatography - Tandem Mass Spectrometry
PublikacjaReverse phase liquid chromatography (RP-HPLC)-electrospray ionization-tandem mass spectrometry (ESI-MS-MS) was evaluated for the analysis of TBT using solid phase extraction as sample preparation method. TBT was extracted from acidified water samples (spiked with tripropyltin as internal standard) using reversed phase polymeric Strata-X cartridges. Analytes were eluted from cartridges using acetonitrile-water mixture and the volume...
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Prediction of the Biogenic Amines Index of Poultry Meat Using an Electronic Nose
PublikacjaThe biogenic amines index of fresh chicken meat samples during refrigerated storage was predicted based on the headspace analysis using an electronic nose equipped with an array of electrochemical sensors. The reference biogenic amines index values were obtained using dispersive liquid–liquid microextraction–gas chromatography–mass spectrometry. A prototype electronic nose with modular construction and a dedicated sample chamber...
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Determination of Odor Intensity of Binary Gas Mixtures Using Perceptual Models and an Electronic Nose Combined with Fuzzy Logic
PublikacjaMeasurement and monitoring of air quality in terms of odor nuisance is an important problem. From a practical point of view, it would be most valuable to directly link the odor intensity with the results of analytical air monitoring. Such a solution is offered by electronic noses, which thanks to the possibility of holistic analysis of the gas sample, allow estimation of the odor intensity of the gas mixture. The biggest problem...
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Global and regional economic inequality: Methods of measurement and evidences
PublikacjaThe lack of countries’ statistical income data, comparable across countries and years, seems to be the main reason of controversial conjectures concerning global inequality and its evolution over time. In the databases, which purport to collect income data on a worldwide scale, only some summary statistics (quantile income shares, means, Gini indices) are presented. Therefore, the development of efficient methods of extracting...
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Fast-response optoelectronic detection of explosives’ residues from the nitroaromatic compounds detonation: field studies approach
PublikacjaWe are presenting an application of optoelectronic nitrogen dioxide (NO2) analyzer based on cavity enhanced absorption spectroscopy in the detection of traces of explosives after detonation. It has been shown that the analyzer using blue-violet laser is able to detect explosive residues after the detonation of various amounts of nitroaromatic compounds (75g-1kg) with higher efficiency than the HPLC soil sample testing equipment,...
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Two kinds of oxygen vacancies in lithium titaniate doped with copper as detected by EPR
PublikacjaLithium titanate (Li1+xTi2-xO4) doped with Cu2+ ions was synthesized by sol-gel processing method. The structure and morphology are characterized by X-ray Diffraction (XRD), X-ray Photoemission Spectroscopy (XPS), Scanning Electron Microscopy (SEM) and Electron Paramagnetic Resonance (EPR). Spin Hamiltonian parameters describing Zeeman and hyperfine interaction for 63Cu2+ ions were obtained from EPR spectra simulations. The spectra...