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The electrical, morphological and optical properties of heavily boron-doped diamond sheets as a function of methane concentration in the gas phase
PublikacjaBoron-doped diamonds (BDD) are known for their excellent properties such as high thermal conductivity, high mobility, low absorption in visible light, and biocompatibility. In this work, we investigated the electrical, morphological and optical properties of heavily boron-doped diamond thin sheets as a function of methane concentration in the gas phase. Free-standing diamond sheets were fabricated using a microwave plasma-assisted...
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Development of SPME fiber coatings with tunable porosity for physical confinement of ionic liquids as an extraction media
PublikacjaExtending the use of ionic liquids in sample preparation techniques remains a challenge. This paper presents procedures enabling the easy application of ionic liquids to the SPME technique. For this purpose, two approaches for producing a porous silica coating on a metal rod were investigated. Two silica precursor and porogen systems were used in the research: K2SiO3 + Formamide and Tetramethyl-orthosilicate + Polyethylene oxide....
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Modelowanie ciągów danych z użyciem sieci neuronowych
PublikacjaRozdział opisuje problematykę przetwarzania ciągów danych. Opisane zostały typy ciągów danych: dane sekwencyjne, sekwencje czasowe oraz przebiegi czasowe. Przedstawiona została architektura sieci rekurencyj
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Connection matrix theory for discrete dynamical systems
PublikacjaIn [C] and [F1] the connection matrix theory for Morse decomposition is developedin the case of continuous dynamical systems. Our purpose is to study the case of discrete timedynamical systems.
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Platelets in fetal growth restriction: role of reactive oxygen species, oxygen metabolism, and aggregation.
PublikacjaFetal growth restriction (FGR) is mainly caused by failure of the uteroplacental unit. Theexact pathogenesis remains unclear. The cause is thought to be related to abnormal platelet activation,which may...
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Ionic liquids-based microextraction techniques
PublikacjaIn recent years, the development of highly efficient analytical techniques is of great importance, however, the direct analysis of complex sample matrix is still impossible in many cases. Therefore, the step of sample preparation is commonly involved in an analytical procedure. Over the years, it has been realized that the major source of inaccuracy and imprecision on general analysis results from the operations associated to sample...
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Index filtrations and Morse decomposition for discrete dynamical systems
PublikacjaOn a Morse decomposition of an isolated invariant set of a homeomorphism(discrete dynamical system) there are partial orderings defined by the homeomorphism.These are called admissible orderings of the...
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Social media as an opportunity or a blind alley in social communication and forest education? – Experiences from Poland
PublikacjaThe article characterizes the experiences, problems, and prospects for the development of forest education on social media, which in Poland has been carried out by the Państwowe Gospodarstwo Leśne Lasy Państwowe (National Forest Holding ‘State...
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Beam on elastic foundation with anticlastic curvature: Application to analysis of mode I fracture tests
PublikacjaA first order correction is proposed taking into account both interface elasticity and transverse anticlastic curvature of flexible substrate(s) in the DCB (and related tests). Adherends are represented by Kirchhoff-Love plates, and the interface by Winkler-type elastic foundation. Two functions are introduced, representing evolution of beam deflection along the sample midline and anticlastic curvature along the plate. A method...
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Direct chromatographic methods in the context of green analytical chemistry
PublikacjaWe review analytical protocols based on gas and liquid chromatography (GC and LC), but involving no sample preparation.Green analytical chemistry seeks to minimize negative impacts of analytical chemistry. Direct analytical methods ideally fulfillthis requirement, as they preclude sample preparation - the most polluting step of the analytical procedure.We describe examples of GC methodologies for environmental and food analysis...
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Preparation and characterization of Pt–N/TiO2 photocatalysts and their efficiency in degradation of recalcitrant chemicals
PublikacjaSeries of Pt–N/TiO2 photocatalysts were synthesized using the sol–gel method. The photocatalysts’ characteristics by X-ray diffractometry (XRD), scanning transmission electron microscopy (STEM), diffuse reflectance spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS) showed that sample with the molar ratio Ti:N equal 1:4 and platinum nanoparticles size of about 3 nm had anatase structure, about 94 m2/g specific surface area...
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Artificial Intelligence in the Diagnosis of Onychomycosis—Literature Review
PublikacjaOnychomycosis is a common fungal nail infection that is difficult to diagnose due to its similarity to other nail conditions. Accurate identification is essential for effective treatment. The current gold standard methods include microscopic examination with potassium hydroxide, fungal cultures, and Periodic acid-Schiff biopsy staining. These conventional techniques, however, suffer from high turnover times, variable sensitivity,...
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Novel Complementary Multiple Concentric Split Ring Resonator for Reliable Characterization of Dielectric Substrates with High Sensitivity
PublikacjaAccurate characterization of dielectric substrates with high sensitivity remains an important challenge in a variety of industrial applications. This paper proposes an innovative strategy to address this challenge by developing and optimizing a unique Complementary Multiple Concentric Split Ring Resonator (CMC-SRR). The major goal is to propose a sensor design with increased sensitivity and reliability for dielectric characterization....
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Dielectric Spectroscopy Studies and Modelling of Piezoelectric Properties of Multiferroic Ceramics
PublikacjaCompounds and solid solutions of bismuth ferrite (BiFeO3)—barium titanate (BaTiO3) system are of great scientific and engineering interest as multiferroic and potential high-temperature lead-free piezoelectric materials. In the present paper, the results of research on the synthesis and characterisation of 0.67Bi1.02FeO3–0.33BaTiO3 (67BFBT) ceramics in terms of crystal structure and dielectric and piezoelectric properties are reported....
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A Meta-Analysis of Pulse Arrival Time Based Blood Pressure Estimation
PublikacjaThe paper presents a preliminary meta-analysis of the sample correlation between pulse arrival time (PAT) and blood pressure (BP). The aim of the study was to verify sample correlation coefficient between PAT and BP using an affine model BP = a · P AT + b for systolic and diastolic blood pressure. The databases included in the search were the IEEE Xplore Digital Library, Springer Link and Google Scholar. Only papers from 2005 to...
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Wysokociśnieniowe uszczelnienia ruchu obrotowego wału hydraulicznych maszyn wyporowych
PublikacjaW artykule przedstawiono wyniki badań mające na celu wytypowanie węzła uszczelniającego wał silnika hydraulicznego zapewniającego najwyższą trwałość przy smarowaniu wodą. Parametry pracy: ciśnienie 2 MPa i minimalna prędkość poślizgu uszczelek 2 m/s. Opisano również nowatorski przyrząd, na którym przeprowadzono pomiary wszystkich parametrów węzła uszczelniającego.
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Separation of the effects of notch and macro residual stress on the MFL signal characteristics
PublikacjaMagnetic flux leakage (MFL) distribution for three configurations of samples has been investigated in order to study the influence of notch and plastic deformation separately as well as together. Samples have been made of S355 steel. The MFL signal measurements were carried out along the longest dimension of the sample over a length of 120 mm. Two components of magnetic field were measured: 1) tangential to the main axis and 2)...
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Principles and Developments of Solid-Phase Microextraction
PublikacjaSample preparation has been commonly considered a critical step of the analytical process. In this sense, remarkable efforts have been made to develop efficient sample preparation techniques which could overcome the limitations of conventional approaches. Since its inception in the early 1990’s, solid-phase microextraction (SPME) has become a widespread miniaturized sample preparation technique for extraction and preconcentration...
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Numerical analysis of vacuum drying of a porous body in the integrated domain
Publikacjan the present study, the vacuum drying process of an apple slice is numerically modeled based on a control volume method. Transient two-dimensional Navier– Stokes, energy, moisture, and Luikov equations are solved by numerical coding (Fortran) to simulate the simultaneous heat and mass transfer in the ambient and apple slice, respectively. The privilege of using Luikov's model is that the capillary forces are considered, and a...
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Green aspects of techniques for the determination of currently used pesticides in environmental samples
PublikacjaPesticides are among the most dangerous environmental pollutants because of their stability, mobility and long-term effects on living organisms. Their presence in the environment is a particular danger. It is therefore crucial to monitor pesticide residues using all available analytical methods. The analysis of environmental samples for the presence of pesticides is very difficult: the processes involved in sample preparation are...
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Stateczność czołowego obwałowania nasypu przeciwpowodziowego Jeziora Druzno
PublikacjaPrzedstawiono analizę stateczności czołowego obwałowania przeciwpowodziowego Jeziora Druzno w miejscowości Nowe Dolno. Obliczenia przeprowadzono zarówno w naprężeniach całkowitych jak i efektywnych uproszczoną metodą Bishopa oraz metodą Felleniusa-Peterssona. Uzyskano wysokie wartości minimalnego wskaźnika stateczności, zapewniające znaczny zapas stateczności nasypu podczas długotrwałych piętrzeń wody w jeziorze. Mogłoby to wskazywać...
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Visible light activity of rare earth metal doped (Er3+, Yb3+ or Er3+/Yb3+) titania photocatalysts
PublikacjaA series of Er3+-TiO2, Yb3+-TiO2 and Er3+/Yb3+-TiO2 photocatalysts were obtained via sol-gel method, using rare earth metal (RE) precursor ranging from 0.25 to 10 mol%. The experiments demonstrated that phenol in aqueous solutions was successfully degraded under visible light (> 450 nm) using RE3+-TiO2. The as-prepared samples were characterized by X-ray diffraction (XRD), X-ray photoelectron emission spectroscopy (XPS), UV-Vis...
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Noise and Electro-Ultrasonic Spectroscopy of Conducting PolymerThick Films
PublikacjaThick conducting films based on conducting polymer are characterized by DC conductivity and noise in temperature range 10 to 300 K. Conducting polymers could be used e.g. for the top electrode (cathode) in the solid tantalum or niobium capacitors. On the conducting polymer layer the top layer of carbon/graphite and/or silver polymer based pastes is applied in the capacitor technology. Our samples structure consists of conducting...
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A multi‐industry and cross‐country comparison of technology contribution to formal and informal knowledge sharing processes for innovativeness
PublikacjaThe study explores the impact of organizational information technology (IT) competency on knowledge sharing, both explicit and tacit, in the context of innovativeness of products and processes. Knowledge sharing is then assessed in terms of tacit-to-explicit conversion and the impact of both types of knowledge on organizational innovation. Both process (internal) and product/service (external) innovation are included. As an extension,...
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Measuring radioactive powder samples on the highresolution powder diffraction beamline at the European Synchrotron Radiation Facility
PublikacjaThis laboratory note describes a new sample preparation technique to enable high-resolution powder diffraction experiments at the European Synchrotron Radiation Facility on radioactive samples. The sample preparation involves setting the active material in resin and several layers of encapsulation suitable for measurement at the beamline. This has allowed low-temperature measurements on very small quantities of samples, providing...
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Spectroscopic studies of Nb-doped tricalcium phosphate glass-ceramics prepared by sol-gel method
PublikacjaCalcium-phosphate based glasses and glass-ceramics play a crucial role in the tissue engineering development. Apart from their high biocompatibility and excellent ability to undergo varying degrees of resorbability1, they exhibit relatively high bioactivity and due to that they are commonly used as bone and dental implants. A substantial research effort is devoted to improve calcium-phosphate materials physico-chemical properties...
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Green aspects of techniques for the determination of pesticides in fruits and vegetables
PublikacjaApplied all over the world, pesticides are some of the most dangerous pollutants of the environment because of their stability, mobility, their ability to accumulate in the environment and their consequent long-term adverse effects on living organisms in general and human health in particular. Their presence in the environment is a particular danger. It is therefore crucial to monitor pesticide residues using all available analytical...
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Oznaczanie śladowych ilości związków organicznych w próbkach o złożonych matrycach zgodne z regułami ''zielonej chemii analitycznej''. Krótkołańcuchowe kwasy karboksylowe = Increasingly green approaches to the determination of selected trace organic in complex matrices. Short chain carboxylic acids
PublikacjaNowadays the great stress is put on environment protection and the activities to minimize the effect of chemical analyses on the environment are discussed. When environmentally friendly methodologies of analytes determination are applied the term "green analytical chemistry" is used. In general, the determination of organic compounds in complex matrices, which is a frequent analytical task, requires separation of sample components...
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Doubly miniaturized rat-race hybrid coupler
PublikacjaTwo complementary miniaturization techniques have beenapplied to reduce the size of a rat-race hybrid coupler: (i) conventional microstrip sections have been replaced with their diminished lowimpedance counterparts as the first step of size reduction and (ii) novel fractal-shaped compact microstrip resonant cells dedicated to efficiently shorten low-impedance transmission line segments have been implemented as the second step of...
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Sampling Procedures in Studies of Cloud Water Composition: A Review
PublikacjaThe authors set out and classify the principles of operation of known types of cloud water collectors, and critically review their advantages and drawbacks. Analysis of the literature has yielded information on the parameters of various type of collectors—sampling time, the type of cloud from which the water sample was taken, droplet diameter collected with 50% efficiency (cut off), sample analytes/ parameters determined, types...
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Mechanical Properties of Human Stomach Tissue
PublikacjaThe dataset entitled Determination of mechanical properties of human stomach tissues subjected to uniaxial stretching contains: the length of the sample as a function of the corresponding load (tensile force) and the initial values of the average width and average thickness of the sample. All tests were conducted in a self-developed tensile test machine: PG TissueTester. The dataset allows the coefficients of various models of...
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Effective density of airborne wear particles from car brake materials
PublikacjaPeople living in urban environments are subject to high health risks due to various anthropogenic sources of airborne particulate matter, including wear of transport vehicle brakes. Studies of airborne particles often require an estimate of the effective particle density, a property that allows correct matching of mass and size characteristics measured by different aerosol instruments. In this study we investigated the effective...
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Determination of the active ingredient in pharmaceutical gel formulation by NIR spectroscopy
PublikacjaPharmaceuticals of their intended must be thoroughly controlled. The traditional analytical methods are very costly and time consuming. NIR spectroscopy allows to analyze pharmaceutical materials very quickly and with very low costs. First pharmaceutical applications of the NIR spectroscopy appeared with some incuriosity in the late 1960s. Application of NIR in the contemporary pharmaceutical industry is very large. The most common...
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General concept of reduction process for big data obtained by interferometric methods
PublikacjaInterferometric sonar systems apply the phase content of the sonar signal to measure the angle of a wave front returned from the seafloor or from a target. It collect a big data – datasets that are so large or complex that traditional data processing application software is inadequate to deal with them. The recording a large number of data is associated with the difficulty of their efficient use. So data have to be reduced. The main...
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Knowledge Sharing and Organizational Culture Dimensions: Does Job Satisfaction Matter?
PublikacjaThe aim of this study is to examine how job satisfaction influences the relationship between company performance, knowledge sharing, and organizational culture, perceived through the prism of Hofstede’s cultural dimensions, controlled by company size and staff position. A survey of 910 Polish employees (mainly knowledge workers) with different roles and experiences across different industries was conducted. The data were analyzed...
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Sleep alterations in treatment-resistant depression patients undergoing ketamine treatment
PublikacjaBackground This study examines self-reported sleep alterations in treatment-resistant depression (TRD) inpatients following intravenous ketamine administration. Methods This is a post-hoc analysis of a naturalistic observational study, which enrolled 28 inpatients with treatment-resistant major depressive disorder and analyzed self-reported sleep changes (items 1–4; ‘insomnia’, ‘nighttime restlessness’, ‘early morning waking’,...
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Hydrophobic deep eutectic solvents in microextraction techniques–A review
PublikacjaOver the past decade, deep eutectic solvents (DES) have been widely studied and applied in sample preparation techniques. Until recently, most of the synthesized DES were hydrophilic, which prevented their use in the extraction of aqueous samples. However, after 2015 studies on the synthesis and application of hydrophobic deep eutectic solvents (HDES) has rapidly expanded. Due to unique properties of HDES i.e. density, viscosity,...
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Analysis of arsenic species in environmental samples
PublikacjaMany analytical methods for determining arsenic in various forms in environmental samples have been developed in recent years. The main objective of this review article is the presentation and comparison of the three principal techniques for the determination arsenic compounds, namely: hydride generation (HG), voltammetry and chromatography (liquid chromatography including high-performance liquid chromatography (HPLC), and gas...
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Microextraction by packed sorbent: Uncommon detection techniques, sorbents, samples and analytes
PublikacjaAmong sample preparation approaches, the most desirable are procedures that ensure high efficiency and reproducibility, that are cheap, fast and simple, that minimize the number of operational steps and that require a small amount of sample and solvent and are thus environmentally friendly. Microextraction by packed sorbent (MEPS) is a miniaturized form of solid-phase extraction, the use of which has been continuously expanding...
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The properties of reduced Ge-Sb-O glasses for thermoelectric devices
PublikacjaThe structural and electrical properties of germanium-antimonate glasses after heat treatment in hydrogen have been determined. In the case of 50GeO2-50Sb2O3 glass reduced at 340°C even for less than 1 hour a continuous layer of antimony granules is formed and its electrical properties determine the surface conductivity of the reduced sample. The bulk electrical conductivity at 100°C of this sample was determined as 1000 Scm-1...
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Miniaturized uniplanar triple-band slot dipole antenna with folded radiator
PublikacjaA miniaturized uniplanar slot dipole for triple-frequency operation is presented. The antenna consists of a folded slot radiator with an increased number of degrees of freedom that allow for efficient size reduction. Rigorous electromagnetic (EM)-driven design optimization is applied in order to achieve the smallest possible size while maintaining acceptable levels of antenna reflection at the required operating frequencies. The...
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THE EFFECT OF WOOD DRYING METHOD ON THE GRANULARITY OF SAWDUST OBTAINED DURING THE SAWING PROCESS USING THE FRAME SAWING MACHINE
PublikacjaThe experimental results of the study focused on the effect of drying processes of warm air drying at the temperature of 6580°C and warm air-steam mixture drying at the temperature of 105°C of pine and beech wood to the size of sawdust grains created by cutting using RPW 15M frame saw is presented in the paper. Particle size analysis of dry sawdust was performed using two methods - screening method and optical method based on...
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Improving operating efficiency of a gas turboset via cooperation with an absorption refrigerating machine
PublikacjaThe analysis of increase of ambient air temperature entering the compressor on reduction in power output from the turbine and increase fuel use was conduced. For medium size gas turbine operates in winter and summer conditions elementary power and economical values was calculated. Conditions of the determination of turbine inlet air cooling solution (using thermal storage for reduce equipment size) are presented
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Podejścia i strategie zarządzania wiedzą w przedsiębiorstwach
PublikacjaArtykuł przedstawia przegląd różnego rodzaju strategii zarządzania wiedzą.Jak powszechnie wiadomo, charakterystyka firmy (np. jej wielkość) wpływa na tworzoną i realizowaną w danym przedsiębiorstwie strategię. Należy więc założyć, że charakterystyka ta będzie również wpływała na wybór strategii zarządzania wiedzą, która będzie realizowana w danej firmie. Inne podejście do strategii zarządzania wiedzą będzie potrzebne w małej czy...
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Mechanical and Microstructural Characterization of TIG Welded Dissimilar Joints between 304L Austenitic Stainless Steel and Incoloy 800HT Nickel Alloy
PublikacjaIn this article, the mechanical properties and microstructure of 304L austenitic stainless steel/Incoloy 800HT nickel alloy dissimilar welded joints are investigated. The joints were made of 21.3 mm × 7.47 mm tubes using the TIG process with the use of S Ni 6082 nickel filler metal. No welding imperfections were found and high strength properties of joints were obtained, meeting the assumed acceptance criteria of the product’s...
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Exploring the role of brand experience in driving consumer emotions and engagement with sports brands in Australia
PublikacjaPurpose: This paper aims to fill the theoretical gap in understanding and practical implementation by examining how sports brands in Australia use brand experience to link emotional response and brand engagement. Design/methodology/approach: The study fits into the positivist paradigm. The starting point is the stimulus-organism-response theory. A quantitative method, which is an online survey, was used to collect data. Responses...
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Improvement of derivatized amino acid detection sensitivity in micellar electrokinetic capillary chromatography by means of acid-induced pH-mediated stacking technique
PublikacjaDerivatization is a frequently used sample prepara-tion procedure applicable to the enhancement of analyte de-tection sensitivity. Amino acids mostly require derivatization prior to electrophoretic or chromatographic analysis, especial-ly if spectrophotometric detection is used. This study presents an on-line preconcentration technique for derivatized amino acids. The sensitivity of the method was improved by the utilization of...
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Polytypism and superconductivity in the NbS2 system
PublikacjaWe report on the phase formation and the superconducting properties in the NbS2 system. Specifically, we have performed a series of standardized solid-state syntheses in this system, which allow us to establish a comprehensive synthesis map for the formation of the two polytypes 2H-NbS2 and 3R-NbS2, respectively. We show that the identification of two polytypes by means of X-ray diffraction is not always unambiguous. Our physical...
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WZROST ZATRUDNIENIA W PRZEDSIĘBIORSTWACH MSP problemy badawcze i wyniki
PublikacjaW artykule w pierwszej kolejności przedstawiono główne problemy badawcze związane z zagadnieniem wzrostu i rozwoju przedsiębiorstwa, wskazując na najczęściej stosowane rozwiązania metodyczne w tym zakresie. W dalszej części zaprezentowano wyniki badań empirycznych, dotyczące zmian zatrudnienia oraz planów związanych z rozwojem małych i średnich przedsiębiorstw funkcjonujących na Pomorzu (badania zostały przeprowadzone w 2009 i...
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Granulometric analysis to etimate influence of anionic surfactrant on activated sludge structure
PublikacjaThe work concerns the evaluation of the possibility of using laser diffraction analyzer to determine changes in the distribution of sludge floc size in the presence of anionic surfactant. As a model of surfactant linear alkylbenzyne sulphonate (LAS) was used. The granulometric analysis showed that the pure activated sludge was composed of particles with a size of 0,001 to 2 mm. The largest and fastest changes in the distribution...