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Properties of Thermally Dewetted Thin Au Films on ITO-Coated Glass for Biosensing Applications
PublicationNoble metal nanostructures are object of great interest due to their unique optical and electronic properties exploited in nanotechnology, medicine, biochemistry, and surface-enhanced spectroscopies. In this work, the Au nanoparticle (NP) structures for application in biosensing obtained by dewetting are investigated in dependence on their preparation conditions. Structures are produced from thin Au films (5–30 nm) sputtered onto...
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Water: Drinking
PublicationOpisano źródła organicznych i nieorganicznych zanieczyszczeń wody do picia w tym: lotnych związków chlorowcoorganicznych, pestycydów, wielopierścieniowych węglowodorów aromatycznych, polichlorowanych bifenyli, fenoli, kwasów chlorooctowych, aldehydów, ketonów itp. a także metody ich oznaczania. Przedstawiono schemat technik izolacji i oznaczania końcowego oraz schemat metod wykorzystujących analizę fazy nadpowierzchniowej. Opisano...
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Titania Nanotubes/Hydroxyapatite Nanocomposites Produced with the Use of the Atomic Layer Deposition Technique: Estimation of Bioactivity and Nanomechanical Properties
PublicationTitanium dioxide nanotubes/hydroxyapatite nanocomposites were produced on a titanium alloy (Ti6Al4V/TNT/HA) and studied as a biocompatible coating for an implant surface modification. As a novel approach for this type of nanocomposite fabrication, the atomic layer deposition (ALD) method with an extremely low number of cycles was used to enrich titania nanotubes (TNT) with a very thin hydroxyapatite coating. X-ray diffraction (XRD)...
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Wpływ metody trawienia i spiekania na właściwości mechaniczne powłok z nanorurek węglowych osadzonych elektroforetycznie na podłożu Ti13Nb13Zr
PublicationDo eksperymentu użyto stopu tytanu Ti13Zr13Nb, który ze względu na swój skład chemiczny i właściwości mechaniczne stanowi doskonały materiał do zastosowań w inżynierii medycznej. Celem pracy była ocena wpływu przygotowania podłoża (rodzaj zastosowanego odczynnika trawiącego) oraz obróbki końcowej (proces spiekania) powłok z wielościennych nanorurek węglowych na ich właściwości mechaniczne (nanotwardość, moduł Younga). Do wytworzenia...
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The Production Possibility of the Antimicrobial Filaments by Co-Extrusion of the PLA Pellet with Chitosan Powder for FDM 3D Printing Technology
PublicationThe last decades have witnessed a major advancement and development in three-dimensional (3D) printing technology. In the future, the trend’s utilization of 3D printing is expected to play an important role in the biomedical field. This work presents co-extrusion of the polylactic acid (PLA), its derivatives (sPLA), and chitosan with the aim of achieving filaments for printing 3D objects, such as biomedical tools or implants. The...
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The effect of dehydration/rehydration of bacterial nanocellulose on its tensile strength and physicochemical properties
PublicationBacterial nanocellulose (BNC) is a natural biomaterial with a wide range of biomedical applications. BNC contains 99 % of water which makes it too thick to be used as a bioimplant material. The aim of the work was to determine the effect of the BNC dehydration followed by rehydration on its mechanical and physicochemical properties, in the context of the use of BNC as bio-prostheses in the cardiovascular system. Dehydration involved the...
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Bio-Based Polyurethane Composites and Hybrid Composites Containing a New Type of Bio-Polyol and Addition of Natural and Synthetic Fibers
PublicationThis article describes how new bio-based polyol during the liquefaction process can be obtained. Selected polyol was tested in the production of polyurethane resins. Moreover, this research describes the process of manufacturing polyurethane materials and the impact of two different types of fibers—synthetic and natural (glass and sisal fibers)—on the properties of composites. The best properties were achieved at a reaction temperature...
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The Effect of C45 Carbon Black-Phosphomolybdic Acid Nanocomposite on Hydrogenation and Corrosion Resistance of La2Ni9Co Hydrogen Storage Alloy
PublicationIn this paper, we analysed the influence of corrosion processes and the addition of a carbon black-heteropoly phosphomolybdic acid (C45-MPA) nanocomposite on the operating parameters of a hydride electrode obtained on the basis of the intermetallic compound La2Ni9Co. The electrochemical properties of negative electrodes for NiMH batteries were studied using galvanostatic charge/discharge curves, the potentiostatic method, and electrochemical...
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Facile synthesis and characterization of graphene and N-doped graphene by CVD method from liquid precursors for promising electrode materials
PublicationIn this study, high-quality and few-layered graphene was synthesized using the chemical vapor deposition (CVD) method from liquid sources. Two different liquid carbon sources, pyridine, and benzene, were used and deposited on nickel foam under heat conditions using a bubbler in a quartz tube. X-ray diffraction (XRD) and Raman analysis confirmed the crystalline properties of graphene and N-doped graphene, demonstrating the high...
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A solid phase extraction–ion chromatography with conductivity detection procedure for determining cationic surfactants in surface water samples
PublicationA new analytical procedure for the simultaneous determination of individual cationic surfactants (alkyl benzyl dimethyl ammonium chlorides) in surface water samples has been developed. We describe this methodology for the first time: it involves the application of solid phase extraction (SPE – for sample preparation) coupled with ion chromatography–conductivity detection (IC-CD – for the final determination). Mean recoveries of...
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Effect of Laser Treatment on Intrinsic Mechanical Stresses in Titanium and Some of Its Alloys
PublicationLaser surface treatment conducted at different power levels is an option to modify titanium bone implants to produce nano- and microtopography. However, such processing can lead to excess mechanical stress within the surface layer. This research aims to calculate the level of such residual stresses after the surface processing of Ti grade IV, Ti15Mo, and Ti6Al7Nb alloys with an Nd:YAG laser. Light and scanning electron microscopies...
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Justyna Szostak dr inż.
PeopleI Gdańsk University of Technology: Chair of the Rector’s Internationalization Committee (October 2020 - Present) Erasmus + Coordinator for students and staff members, Faculty of Applied Physics and Mathematics (Mar 2017 - Present) Dean's Proxy for Internationalization, Faculty of Applied Physics and Mathematics (October 2020 - Present) Coordinator of the International Relations Office of the Faculty of Applied Physics and...
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On the origin of surfaces-dependent growth of benzoic acid crystal inferred through the droplet evaporation method
PublicationCrystal growth behavior of benzoic acid crystals on different surfaces was examined. The performed experiments documented the existence of very strong influence introduced by polar surfaces as glass, gelatin, and polyvinyl alcohol (PVA) on the growth of benzoic acid crystals. These surfaces impose strong orientation effect resulting in a dramatic reduction of number of faces seen with x-ray powder diffractions (XPRD). However,...
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On the origin of surfaces-dependent growth of benzoic acid crystal inferred through the droplet evaporation method
PublicationCrystal growth behavior of benzoic acid crystals on different surfaces was examined. The performed experiments documented the existence of very strong influence introduced by polar surfaces as glass, gelatin, and polyvinyl alcohol (PVA) on the growth of benzoic acid crystals. These surfaces impose strong orientation effect resulting in a dramatic reduction of number of faces seen with x-ray powder diffractions (XPRD). However,...
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On the origin of surfaces-dependent growth of benzoic acid crystal inferred through the droplet evaporation method
PublicationCrystal growth behavior of benzoic acid crystals on different surfaces was examined. The performed experiments documented the existence of very strong influence introduced by polar surfaces as glass, gelatin, and polyvinyl alcohol (PVA) on the growth of benzoic acid crystals. These surfaces impose strong orientation effect resulting in a dramatic reduction of number of faces seen with x-ray powder diffractions (XPRD). However,...
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THE PROTECTIVE MEASURES AGAINST SARS-COV-2 INFECTION IN THE SEAFOOD COMPANY FROM THE PERSPECTIVE OF THE EMPLOYEES
PublicationPurpose: To identify and discuss the protective measures implemented to prevent SARS-CoV-2 infection among employees. Design/methodology/approach: The four-stage course of research. Case study and structured interviews with all employees, directly and indirectly, involved in food processing. Research questions: (R1) What measures have been taken to prevent the risk of infection among employees? (R2) What activities and responsibilities...
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Partial inhibition of borohydride hydrolysis using porous activated carbon as an effective method to improve the electrocatalytic activity of the DBFC anode
PublicationCarbon materials are commonly used catalyst supports in various types of fuel cells. Due to the possibility of designing their properties, they seem to be attractive and functional additives. In Direct Borohydride Fuel Cells (DBFCs), the electrooxidation reaction of borohydride competes with the undesirable hydrolysis reaction, therefore our work aimed to modify anodes based on a multi-component hydrogen storage alloy with a small...
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Microextraction Techniques Used in the Procedures for Determining Organomercury and Organotin Compounds in Environmental Samples
PublicationDue 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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Numerical analysis of elastic wave propagation in unbounded structures
PublicationThe main objective of this paper is to show the effectiveness and usefulness of the concept of an absorbing layer with increasing damping (ALID) in numerical investigations of elastic wave propagation in unbounded engineering structures. This has been achieved by the authors by a careful investigation of three different types of structures characterised by gradually increasing geometrical and mathematical description complexities....
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Application of Open-Hardware-Based Solutions for Rapid Transition From Stationary to the Remote Teaching Model During Pandemic
PublicationWhile research indicates usefulness of remote laboratories in teaching of digital hardware systems, their main application is to complement stationary classes. This work presents a low-cost, scalable architecture that supports rapid transformation of teaching to a model based solely on remote access mechanisms. Background: Adaptation of online laboratory solutions from the literature to en-masse teaching of digital circuits is...
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Diamine derivatives of dimerized fatty acids and bio-based polyether polyol as sustainable platforms for the synthesis of non-isocyanate polyurethanes
PublicationA series of environmentally friendly non-isocyanate polyurethanes (NIPUs) were successfully prepared via the polyaddition reaction of bio-based polyether polyol-based cyclic carbonate with diamine derivative of dimerized fatty acids. The syntheses of NIPUs were realized by the three-step method in the absence of toxic solvents and, importantly, the process of carbonation did not require the use of elevated pressure. The effect...
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Zastosowanie nowych typów materiałów sorpcyjnych w ekstrakcji analitów z próbek biologicznych
PublicationW obecnych czasach wiele uwagi w chemii anlityczanej poświęca się bezrozpuszczalnikowym technikom przygotowania próbki do analizy. Wynika to z potrzeby opracowania szybkich i rzetelnych procedur analitycznych prowadzących do obniżenia granic wykrywalności. Jedna z najbardziej obiecujących technik w tej dziedzinie to ekstrakcja do fazy stacjonarnej, która jest szeroko stosowana w praktyce analitycznej ze względu na jej niewątpliwe...
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Determination of Selected Metals in Fruit Wines by Spectroscopic Techniques
PublicationThe determination of metals in different types of food and beverages samples has drawn significant attention due to several reasons with the most important one being the nutritional and toxic effects of these elements or their compounds. The knowledge of certain elements content in wines/fruit wines is of special interest due to their toxicity in case of excessive intake and also the effect they seem to have on the organoleptic...
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Moving Towards Competence in Teaching Architecture: The Relationship of Research and Design in Academia
PublicationArchitecture is truly a profession of public trust requiring special care at all stages in academic education. European educational reforms initiated by the 1999 Bologna Process affected architecture education, and shifted the role of research. The number of doctoral programs increased, so the involvement of PhD students in teaching also expanded. This study aims to identify how these changes affect quality in architecture education....
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Photocatalytic and Antimicrobial Properties of Ag2O/TiO2 Heterojunction
PublicationAg2O/TiO2 heterojunctions were prepared by a simple method, i.e., the grinding of argentous oxide with six different titania photocatalysts. The physicochemical properties of the obtained photocatalysts were characterized by diffuse-reflectance spectroscopy (DRS), X-ray powder diffraction (XRD) and scanning transmission electron microscopy (STEM) with an energy dispersive X-ray spectroscopy (EDS). The photocatalytic activity was...
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Impact of influent wastewater quality on nitrogen removal rates in multistage treatment wetlands
PublicationNitrogen removal in treatment wetlands is influenced by many factors, and the presence of electron donors (biodegradable organic matter) and electron acceptors (nitrate ions) is the main limiting one; for obtaining these conditions, multistage treatment wetlands (MTWs) are required, where an extensive nitrification can be obtained in the first stages under aerobic conditions leaving then to the following anoxic/anaerobic stages...
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New coordination polymers based on a V-shaped ligand and lanthanides: Structural description and symmetry-luminescence correlation using europium as a probe
PublicationWe have synthesized new luminescent coordination polymers using 4,4'-sulfonyldibenzoic acid (H2SDA) and several lanthanide ions by open crystallization in DMF. Three different 1-D structures were obtained, as determined by single-crystal X-ray diffraction: [La(η2-NO3)(μ-SDA)(DMF)3]n (1), [Sm(η2-NO3)(μ-SDA)(DMF)2 2DMF]n (3), [Ln(η2-NO3)(μ-SDA)(DMF)2 DMF]n (Ln ¼ Eu (4), Dy (5), Ho (6), Er (7), Tm (8) and Lu(9)). A 2-D structure,...
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Evaluation of Connectivity Gaps Impact on TCP Transmissions in Maritime Communications
PublicationMany organizations and research working groups, including among others IEEE, ITU, ETSI and IMO are currently working towards improvements in communication of different types of vehicles (cars, trains, planes and vessels) and upgrading utilities and services offered to their crews and passengers travelling all over the world. The paper deals with selected aspects of the TCP protocol connectivity in maritime wireless networks. The...
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Chemical Aspects of Biological Activity of Isothiocyanates and Indoles, the Products of Glucosinolate Decomposition
PublicationThere is growing evidence that cancer chemoprevention employing natural, bioactive compounds may halt or at least slow down the different stages of carcinogenesis. A particularly advantageous effect is attributed to derivatives of sulfur-organic phytochemicals, such as glucosinolates (GLs) synthesized mainly in Brassicaceae plant family. GLs are hydrolysed enzymatically to bioactive isothiocyanates (ITC) and indoles, which exhibit strong...
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A Method of Fast and Simultaneous Calibration of Many Mobile FMCW Radars Operating in a Network Anti-Drone System
PublicationA market for small drones is developing very fast. They are used for leisure activities and exploited in commercial applications. However, there is a growing concern for accidental or even criminal misuses of these platforms. Dangerous incidents with drones are appearing more often, and have caused many institutions to start thinking about anti-drone solutions. There are many cases when building stationary systems seems to be aimless...
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Insights into oral microbiome and colorectal cancer – on the way of searching new perspectives
PublicationMicrobiome is a keystone polymicrobial community that coexist with human body in a beneficial relationship. These microorganisms enable the human body to maintain homeostasis and take part in mechanisms of defense against infection and in the absorption of nutrients. Even though microbiome is involved in physiologic processes that are beneficial to host health, it may also cause serious detrimental issues. Additionally, it has been...
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Linear impedance of 10Na2O–60P2O5–30CaO glass measured with impedance spectroscopy method at low temperature region
Open Research DataThe linear electrical properties of 10Na2O–60P2O5–30CaO glass was measured by impedance spectroscopy method.
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Degradation of cefadroxil drug by newly designed solar light responsive alcoholic template-based lanthanum ferrite nanoparticles
PublicationIn this work, lanthanum ferrite nanoparticles were synthesized via a simple co-precipitation method. Two different templates, namely sorbitol and mannitol, were used in this synthesis to tune the optical, structural, morphological, and photocatalytic properties of lanthanum ferrite. The synthesized lanthanum ferrite-sorbitol (LFOCo-So) and lanthanum ferrite-mannitol (LFOCo-Mo) were investigated through Ultraviolet–Visible (UV–Vis),...
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High-density Polyethylene - Expanded Perlite Composites: Structural Oriented Analysis of Mechanical and Thermomechanical Properties
PublicationAs part of this work, research was carried out on the effect of the addition of expanded perlite (PR) on the mechanical and thermomechanical properties of high-density polyethylene (PE) composites. Composites containing from 1 to 10 wt% of the inorganic filler were produced. Polyethylene-based composites manufactured by twin-screw extrusion and formed in the compression molding process were subjected to mechanical, thermomechanical,...
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Effect of cobalt addition on the corrosion behaviorof near equiatomic NiTi shape memory alloy in normal saline solution: electrochemical and XPS studies
PublicationThe electrochemical and corrosion (uniform and localized) behavior of a binary Ni52Ti48 shape memory alloy (SMA) and two ternary Ni52Ti48-xCox (x = 1.5 and 4.0 wt.%) SMAs were studied. Measurements were conducted in 0.9% NaCl solution at 37 oC employing various electrochemical methods. These include: linear polarization resistance (LPR), linear sweep voltammetry (LSV), chronoamperometry and dynamic electrochemical impedance spectroscopy...
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Personal Brand Authenticity and Social Media: The Top 5 Football Players’ Case
Publicationhe authenticity is a key factor which attracts the interest of young consumers in the more and more dominant virtual world full of “fake news”,“fake images”, and “fake impressions”. The celebrity authenticity is also important when it comes to gain the positive attitude of the audience and the success in the long term. The unique talent is crucial for all stars. According to football stars, the authenticity of their personal brands...
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Cu supported on various oxides as a candidate catalyst for dry methane reforming in DIR-SOFCs systems
PublicationA series of Cu-support systems were tested as potential candidates for DIR-SOFC (Direct Internal Reforming SOFC) catalysts towards a dry reforming of methane (DRM). The various supports (-Al2O3, CeO2, ZrO2, SrTiO3) with comparable specific surface area (SSA), and additionally -Al2O3 with SSA an order of magnitude larger than that of the other supports has been applied. The obtained Cu-support systems were characterized in terms...
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Effect of Pin Shape on Thermal History of Aluminum-Steel Friction Stir Welded Joint: Computational Fluid Dynamic Modeling and Validation
PublicationThis article studied the effects of pin angle on heat generation and temperature distribution during friction stir welding (FSW) of AA1100 aluminum alloy and St-14 low carbon steel. A validated computational fluid dynamics (CFD) model was implemented to simulate the FSW process. Scanning electron microscopy (SEM) was employed in order to investigate internal materials’ flow. Simulation results revealed that the mechanical work...
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Tuning of the plasmon resonance location in Au nanostructures coated with a ultrathin film of Al2O3 – Optical measurements and FDTD simulations
PublicationThe Au nanostructures have been coated with an ultra-thin films of amorphous aluminium oxide. Optical absorption spectra show the influence of the thickness of Al2O3 on plasmon resonance wavelength. The observed red-shift of the resonance location with the increase of the thickness of the Al2O3 film, can be explained by the change in the dielectric function of this film. It allows control of the optical spectra of the coated particles....
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Mechanizmy zniszczenia kompozytów epoksydowych wzmocnionych włóknami węglowymi i aramidowymi.
PublicationW celu obniżenia ryzyka gwałtownego pękania oraz masy konstrukcji, laminaty wzmocnione włóknami węglowymi mogą być zastępowane przez hybrydowe aramidowo-węglowe. Problemem jest zachowanie pod obciażeniem przy okresowym zanurzeniu w wodzie. Przedstawiono mapy naprężeń oraz odkształceń niszczących w laminatch epoksydowych wzmocnionych tkaninami węglową i aramidową opracowane w oparciu o badania wytrzymałości na zginanie próbek w...
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Luminescence recognition material as an INHIBIT logic gate in presence of Pb2+ and Cu2+ ions in aqueous solutions
PublicationA recognition material consisting of silica xerogel with amino-modified surface selectively recognizes Pb2+ and Cu2+ (but only in presence of Pb2+ ions) in aqueous solutions of other metal ions. The analytical action of the material is based on a significant change in luminescence emission spectra of the material after chemisorption of Pb2+ ions. In the presence of Pb2+ in octahedral coordination environment, a new broad and strong...
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Novel Class of Proton Conducting Materials—High Entropy Oxides
PublicationHere, for the first time, we present data on proton conductivity of high-entropy, single-phase perovskites. The BaZr0.2Sn0.2Ti0.2Hf0.2Ce0.2O3−δ, BaZr0.2Sn0.2Ti0.2Hf0.2Y0.2O3−δ, BaZr1/7Sn1/7Ti1/7Hf1/7Ce1/7Nb1/7Y1/7O3−δ, and BaZr0.15Sn0.15Ti0.15Hf0.15Ce0.15Nb0.15Y0.10O3−δ single-phase perovskites were synthesized. Before electrical measurements, materials were characterized using X-ray diffraction (XRD), scanning electron microscopy...
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Selected concentration techniques for gas chromatographic analysis of environmental samples
PublicationThe paper describes the role and tasks of environmental analysis and monitoring. It emphasises the leading role played by gas chromatography, especially when coupled with suitable sample preparation. This is demonstrated by some literature evidence and mainly by the author's original work on the design of sample preparation apparatus and development of GC-based methods of determination of a wide variety of organic pollutants in...
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Spectroscopic evaluation on pseudopolymorphs of sodium naproxen
PublicationThis paper demonstrates the assessment of vibrational spectroscopy methods such as middle infrared, near infrared and Raman spectroscopy (FTIR, FT-NIR, Raman) for the identification of pseudopolymorphic forms of a model active pharmaceutical ingredient (API) - sodium naproxen (NpxNa). NpxNa, in the form of three different pseudopolymorphs, was investigated by methods dedicated for solid state characterization: DSC (differential...
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Organic semiconductor rubrene thin films deposited by pulsed laser evaporation of solidified solutions
PublicationOrganic semiconductor rubrene (C42H28) belongs to most preferred spintronic materials because of the high charge carrier mobility up to 40 cm2(V·s)-1. However, the fabrication of a defect-free, polycrystalline rubrene for spintronic applications represents a difficult task. We report preparation and properties of rubrene thin films deposited by pulsed laser evaporation of solidified solutions. Samples of rubrene dissolved in aromatic...
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Properties of ordered titanium templates covered with Au thin films for SERS applications
PublicationtCurrently, roughened metal nanostructures are widely studied as highly sensitive Raman scattering sub-strates that show application potential in biochemistry, food safety or medical diagnostic. In this workthe structural properties and the enhancement effect due to surface enhanced Raman scattering (SERS) ofhighly ordered nano-patterned titanium templates covered with thin (5–20 nm) gold films are reported.The templates are formed...
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The Effect of Calcination Temperature on Structure and Photocatalytic Properties of WO3/TiO2 Nanocomposites
PublicationSeries ofWO3/TiO2 nanocompositeswere obtained by hydrothermal method followed by calcination in the temperature range from 400∘C to 900∘C. The characteristics of photocatalysts by X-ray diffractometry (XRD), scanning electron microscope (SEM), and diffuse reflectance spectroscopy (DRS) showed that increasing the calcination temperature from 400 to 900∘C resulted in change of photocatalytic activity under UV-Vis light.Moreover,...
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Synthesis and structural properties of (Y, Sr)(Ti, Fe, Nb)O3−δ perovskite nanoparticles fabricated by modified polymer precursor method
PublicationThe yttrium, iron and niobium doped-SrTiO3 powders have been successfully fabricated by a modified low–temperature synthesis method from a polymer complex. The usage of strontium hydroxide precursor instead of conventional strontium nitrate or strontium carbonate provides to the possibility of significant decrease of annealing temperature. It allows to prepare a material with sphere-shape grains of nanometric size (15–70 nm). The...
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Softwood-lignin/natural rubber composites containing novel plasticizing agent: Preparation and characterization
PublicationComposite materials based on natural rubber were obtained by using glycerolysate (decomposition prod- uct of polyurethane) as a novel plasticizer. In order to determine the effect of various lignin content, four different filler amounts were used, namely, 5 phr (parts per 100 parts of natural rubber) of lignin (WLI5G), 10 phr (WLI10G), 20 phr (WLI20G), and 40 phr (WLI40G). The reference specimen without lignin (WLI0G) was also...
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Assessment of the impact of bacteria Pseudomonas denitrificans, Pseudomonas fluorescens, Bacillus subtilis and yeast Yarrowia lipolytica on commercial poly(ether urethanes)
PublicationThe assessment of the impact of the bacteria Pseudomonas denitrificans, Pseudomonas fluorescens, Bacillus subtilis and yeast Yarrowia lipolytica on commercial poly(ether urethanes) Tecoflex® and Tecothane® is presented. The polyurethane samples were incubated with pure cultures of the microorganisms at 30 °C for five months. The changes in the chemical structure of the polymers were evaluated using loss of weight and contact angle...