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Search results for: PHOTOACOUSTIC SPACTROSCOPY
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Development of the Mobile PoC Graphene-Based Biosensing Device Using Electrochemical Impedance Spectroscopy (EIS)
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Discrimination of Apple Liqueurs (Nalewka) Using a Voltammetric Electronic Tongue, UV-Vis and Raman Spectroscopy
PublicationThe capability of a phthalocyanine-based voltammetric electronic tongue to analyze strong alcoholic beverages has been evaluated and compared with the performance of spectroscopic techniques coupled to chemometrics. Nalewka Polish liqueurs prepared from five apple varieties have been used as a model of strong liqueurs. Principal Component Analysis has demonstrated that the best discrimination between liqueurs prepared from different...
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Charge-based deep level transient spectroscopy of B-doped and undoped polycrystalline diamond films
PublicationThe undoped and B-doped polycrystalline diamond thin film was synthesized by hot filament chemical vapor deposition and microwave plasma, respectively. The structural characterization was performed by scanning electron microscopy, X-ray diffraction and Raman spectroscopy. The electrical properties of synthesized diamond layer were characterized by dc-conductivity method and charge deep level transient spectroscopy. The B-doped...
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Local Structure and Stability of SEI in Graphite and ZFO Electrodes Probed by As K-edge Absorption Spectroscopy
PublicationThe evolution of the solid electrolyte interphase (SEI) during the first Li uptake in advanced Li-ion electrodes is studied by X-ray absorption spectroscopy (XAS). The As atoms present in the electrolyte solution were used as a local probe for monitoring the SEI growth on different electrodes. High-quality As K-edge spectra were collected in fluorescence mode for a set of graphite and carbon-coated ZnFe2O4 electrodes. XAS measurements...
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EXAMINATION OF SOL-GEL DERIVED HYDROXYAPATITE ENHANCED WITH SILVER NANOPARTICLES USING OCT AND RAMAN SPECTROSCOPY
PublicationHydroxyapatite (HAp) has been attracting widespread interest in medical applications. In a form of coating, it enables to create a durable bond between an implant and surrounding bone tissues. With addition of silver nanoparticles HAp should also provide antibacterial activity. The aim of this research was to evaluate the composition of hydroxyapatite with silver nanoparticles in a non-destructive and non-contact way. For control measurements...
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Absorption spectroscopy setup for determination of whole human blood and blood–derived materials spectral characteristics
PublicationA dedicated absorption spectroscopy system was set up using tungsten-halogen broadband source, optical fibers, sample holder, and a commercial spectrometer with CCD array. Analysis of noise present in the setup was carried out. Data processing was applied to the absorption spectra to reduce spectral noise, and improve the quality of the spectra and to remove the baseline level. The absorption spectra were measured for whole blood...
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Optical emission spectroscopy of plasma generated by a waveguide-supplied microwave plasma source operated at 915MHz
PublicationIn this paper we present the results of an optical emission spectroscopic study of an atmospheric pressure microwave (915 MHz) nitrogen and nitrogen with carbon dioxide (1%) plasma at high working gas flow rate. This study was aimed at determining rotational Trot and vibrational Tvib temperatures of N+2 ions and N2, CN molecules. The plasma was generated in a waveguide-supplied cavity-resonant type microwave plasma source. All...
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Enhanced capacitance of composite TiO2 nanotube / boron-doped diamond electrodes studied by impedance spectroscopy
PublicationWe report on the novel composite nanostructures based on boron-doped diamond thin film grown on top of TiO2 nanotubes. The nanostructures made of BDD-modified titania nanotubes showed an increase in activity and performance when used as electrodes in electrochemical environments. The BDD thin films (~200-500 nm) were deposited using microwave plasma assisted chemical vapor deposition (MW PA CVD) onto anodically fabricated TiO2...
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A measurement system for nonlinear surface spectroscopy with an atomic force microscope during corrosion process monitoring
PublicationIn addition to traditional imaging the surface, atomic force microscopy (AFM) enables wide variety of additional measurements. One of them is higher harmonic imaging. In tapping mode the nonlinear contact between tip and specimen results in higher frequency vibrations. More information available from the higher harmonics analysis proves to be helpful for more detailed imaging. Such visualization is espe-cially useful for heterogeneous...
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Higher harmonics of the intensity modulated Photocurrent/Photovoltage spectroscopy response - a tool for studying photoelectrochemical nonlinearities
PublicationIn this work, a higher harmonic analysis (HHA) of the intensity modulated photocurrent/photovoltage (IMPS/IMVS) spectroscopy data is proposed as a potent tool for studying nonlinear phenomena in photoelectrochemical and photovoltaic systems. Analytical solutions of kinetic equations were constructed for cases of single and double resonance accounting for various sources of higher harmonics. These sources correspond to the physical...
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Dissolution of Nb-doped hydroxyapatite prepared via low-temperature mechanochemical method: Spectroscopy studies
PublicationCalcium phosphate glass ceramics with nominal hydroxyapatite stoichiometry doped with niobium were synthesized using simple as well as low-temperature mechanochemical method and then in the form of compressed pellet were submitted to the static dissolution process in distilled water for one month. The results of structural analysis, performed mainly on the base of spectroscopic methods such as: infrared absorption spectroscopy,...
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Analysis of friction ridge evidence for trace amounts of paracetamol in various pharmaceutical industries by Raman spectroscopy
PublicationThe detection of potentially harmful substances presents a multifaceted challenge. On one hand, it can directly save lives, on the other, it can significantly aid and enhance police work, thereby increasing the effectiveness of investigations. The research conducted in this study primarily aims to identify paracetamol in fingerprints, considering situations involving direct contact of a person with paracetamol either chronically...
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Selective adsorption of BTEX on calixarene-based molecular coordination network determined by 13C NMR spectroscopy
PublicationBenzene, toluene, ethylbenzene, and xylenes (BTEX), a class of volatile organic compounds, are harmful pollutants but also very important precursors in organic industrial chemistry. Among different approaches used for the BTEX treatment, the adsorption technology has been recognized as an efficient approach because it allows to recover and reuse both adsorbent and adsorbate. However, the selective adsorption of the components is...
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Electrochemical behaviour of Cr coating in acidic sulphate solution studied by cyclic polarization and impedance spectroscopy
PublicationOdporność korozyjną powłok chromowych w 0.01 M H2SO4 zbadano metodami woltamperometrii cyklicznej i spektroskopii impedancyjnej. Stwierdzono, że właściwości ochronne powłoki chromowej w kontakcie z powietrzem wzrastają dzięki tworzeniu się warstwy tlenkowej zapełniającej defekty w powłoce. W trakcie polaryzacji anodowej następuje częściowe roztwarzanie tej warstwy i penetracja agresywnego środowiska do podłoża (stali), co powoduje...
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Dynamic elektrochemical impedance spectroscopy measurements of passive layer cracking under static tensile stresses.
PublicationDynamiczna elektrochemiczna spektroskopia impedancyjna umożliwia badanie podatności i odporności korozyjnej różnych materiałów konstrukcyjnych, a w szczególności określenie właściwości elektrochemicznych warstw pasywnych występujących na ich powierzchni. W wielu przypadkach pęknięcie warstwy pasywnej pod wpływem działania naprężeń rozciągających prowadzi do korozji naprężeniowej. Z tego względu badania pękania warstw pasywnych...
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Dynamic electrochemical impedance spectroscopy measurements of passive layer cracking under static tensile stresses.
PublicationDynamiczna Elektrochemiczna Spektroskopia Impedancyjna umożliwia badanie podatności i odporności korozyjnej różnych materiałów konstrukcyjnych, a w szczególności określenie właściwości elektrochemicznych warstw pasywnych występujących na ich powierzchni. W wielu przypadkach pęknięcie warstwy pasywnej pod wpływem działania naprężeń rozciągających prowadzi do korozji naprężeniowej. Z tego względu badania pękania warstw pasywnych...
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Validity of impedance spectra obtained by dynamic electrochemical impedance spectroscopy verified by Kramers-Kronig transformation.
PublicationArtykuł przedstawia weryfikację wiarygodności widm impedancyjnych otrzymanych za pomocą niedawno wprowadzonej techniki eksperymentalnej - Dynamicznej Elektrochemicznej Spektroskopii Impedancyjnej (Dynamic Electrochemical Impedance Spectroscopy, DEIS). Technika ta zakłada, że badany system jest pseudostacjonarny jeśli czas pomiaru jest odpowiednio krótki. Czas potrzebny na otrzymanie pojedynczego spektrum zależy od długości okna...
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Evaluation of cavitation erosion–corrosion degradation of mild steel by means of dynamic impedance spectroscopy in galvanostatic mode
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Orientational order and dynamics of the dendritic liquid crystal organo-siloxane tetrapodes determined using dielectric spectroscopy
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Enhancement of the efficiency of the third harmonic generation process in ZnO:F thin films probed by photoluminescence and Raman spectroscopy
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Impedance spectroscopy studies on hybrid materials consisting of poly(3,4-ethylenedioxythiophene) and iron, cobalt and nickel hexacyanoferrate
PublicationBadania warstw polimeru pEDOT modyfikowanego heksacyjanożelazianami żelaza, kobaltu i niklu przeprowadzono za pomocą spektroskopii impedancyjnej (SI). Wykazano, że materiały hybrydowe charakteryzują się dobrą stabilnością. Warstwy testowano w zakresie temperatur od 283 do 313K. w kontakcie z wodnym roztworem KCl. Wysokie współczynniki dyfuzji wskazują na możliwości wykorzystania układów jako przewodników jonowych.
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Super Broadband Near-Infrared Phosphors with High Radiant Flux as Future Light Sources for Spectroscopy Applications
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Application of Raman Spectroscopy to Evaluate the Structure Changes of Lubricating Grease Modified with Montmorillonite after Tribological Tests
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Evaluation of cavitation erosion-corrosion degradation of mild steel by means of Dynamic Impedance Spectroscopy in galvanostatic mode
PublicationPrzedstawiono wyniki badań degradacji stali węglowych na skutek oddziaływania erozji-korozji kawitacyjnej. Do analizy wykorzystano technikę Dynamicznej Elektrochemicznej Spektroskopii Impedancyjnej w trybie galwanostatycznym, bliżej odwzrorowującym warunki naturalne. Do oceny stopnia degradacji posłużyły również funkcja ubytku masy MDPR oraz obrazy mikroskopowe SEM. Potwierdzono wpływ łączonej degradacji erozyjno-korozyjnej na...
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Conformational studies of [Nphe5]SFTI-1 by means of 2D NMR spectroscopy in conjunction with molecular dynamics calculations
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Structure determination of UL49.5 transmembrane protein from bovine herpesvirus 1 by NMR spectroscopy and molecular dynamics
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Combined analysis of whole human blood parameters by Raman spectroscopy and spectral-domain low-coherence interferometry
PublicationIn this article the simultaneous investigation of blood parameters by complementary optical methods, Raman spectroscopy and spectral-domain low-coherence interferometry, is presented. Thus, the mutual relationship between chemical and physical properties may be investigated, because low-coherence interferometry measures optical properties of the investigated object, while Raman spectroscopy gives information about its molecular...
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Determination of pseudocapacitance chan ges of nickel oxide NiO electrode with use of dynamic electrochemical impedancje spectroscopy
PublicationThe electrochemical capacitors (ECs) are attractive energy storage devices which can be applied in many electronic products (e.g., cameras, laptops, cell phones) or hybrid electric vehicles (HEV). The energy storage in ECs is based on capacitive (the electrical double layer charging/discharging) and pseudocapacitive (additional charge provided by faradic reaction) phenomena. Considering the electrodes exhibiting pseudocapacitance,...
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Optical Emission Spectroscopy of Microwave (915 MHz) Plasma in Atmospheric Pressure Nitrogen with Addition of Ethanol Vapour
PublicationIn this paper results of optical emission spectroscopic study of microwave 915 MHz plasma in atmospheric pressure nitrogen with an addition of ethanol vapour are presented. The plasma was generated in waveguide- -supplied cylinder-type nozzleless microwave plasma source. The aim of research was to determine the rotational Trot and vibrational Tvib temperatures of CN and C2. A method called bubbling was employed to introduce alcohol (ethanol)...
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An Assessment of RASSCF and TDDFT Energies and Gradients on an Organic Donor−Acceptor Dye Assisted by Resonance Raman Spectroscopy
PublicationThe excitation energies and gradients in the ground and the first excited state of a novel donor−(π- bridge)−acceptor 4-methoxy-1,3-thiazole-based chromophore were investigated by means of MS-RASPT2/RASSCF and TDDFT in solution. Within both methods, the excitation energies strongly depend on the employed equilibrium structures, whose differences can be rationalized in terms of bond length alternation indexes. It is shown that functionals with...
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Study of the Layer-Type BST Thin Film with X-ray Diffraction and X-ray Photoelectron Spectroscopy
PublicationIn the present paper, results of X-ray photoelectron studies of electroceramic thin films of barium strontium titanate, Ba1xSrxTiO3 (BST), composition deposited on stainless-steel substrates are presented. The thin films were prepared by the sol-gel method. A spin-coating deposition of BST layers with different chemical compositions was utilized so the layer-type structure of (0-2) connectivity was formed. After the deposition,...
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Electronic States of Tris(bipyridine) Ruthenium(II) Complexes in Neat Solid Films Investigated by Electroabsorption Spectroscopy
PublicationWe present the electric field-induced absorption (electroabsorption, EA) spectra of the solid neat films of tris(bipyridine) Ru(II) complexes, which were recently functionalized in our group as photosensitizers in dye-sensitized solar cells, and we compare them with the results obtained for an archetypal [Ru(bpy)3]2+ ion (RBY). We argue that it is difficult to establish a unique set of molecular parameter values by discrete parametrization...
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New possibilities of the passive layer cracking dynamics detection using a new Dynamic Electrochemical Impedance Spectroscopy.
PublicationNowa metoda Dynamicznej Elektrochemicznej Spektroskopii Impedancyjnej opracowana w Katedrze Elektrochemii, Korozji i Inżynierii Materiałowej Politechniki Gdańskiej daje możliwości określania charakterystyki impedancyjnej w dziedzinie czasu podczas procesu pękania ochronnej warstwy pasywnej. Fakt ten jest związany z procedurą analizującą wspomnianej techniki, która umożliwia selektywną analizę czasowo-częstotliwościową uzyskanych...
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Dynamic Electrochemical Impedance Spectroscopy (DEIS) as a Tool for Analyzing Surface Oxidation Processes on Boron-Doped Diamond Electrodes
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Observation of the de Vries behavior in SmA* phase of a liquid crystal using polarised Raman scattering and infrared spectroscopy
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Trends in biomedical analysis of red blood cells – Raman spectroscopy against other spectroscopic, microscopic and classical techniques
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Determination of occurrence of anodic excursion peaks by dynamic electrochemical impedance spectroscopy, atomic force microscopy and cyclic voltammetry
PublicationStruktura oraz skład warstw anodowych na ołowiu najbardziej zależy od; dodatków stopowych, stężenia kwasu siarkowego oraz od zakresu potencjału. Zjawisko powstawania pików "anodic excursion peaks" od zawsze było w centrum uwagi wielu naukowców. W tej pracy zachowanie się powyższego zjawiska (AEP) zostało zbadane metodami dynamicznej elektrochemicznej spektrokopii impedancyjnej, mikroskopu sił atomowych oraz chronowoltamperometrii....
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Comparison of quenching mechanisms in Gd3Al5−xGaxO12:Ce3+ (x = 3 and 5) garnet phosphors by photocurrent excitation spectroscopy
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Ultra-Broadband Phosphors Converted Near-Infrared Light Emitting Diode with Efficient Radiant Power for Spectroscopy Applications
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LF NMR spectroscopy analysis of water dynamics and texture of Gluten-Free bread with cricket powder during storage
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Using isothermal calorimetry and FT-Raman spectroscopy for step-by-step monitoring of maize seed germination: case study
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Solvation of cobalt(II) ion in N,N-dimethylformamide-methanol mixed solvent: calorimetry and VIS spectroscopy studies
PublicationZmierzono entalpie rozpuszczania trifluorometanosulfonianów Co(II) i Na(I) w mieszaninie N,N-dimetyloformamid(DMF)-metanol(MeOH) w całym zakresie jej składu. Z danych tych wyznaczono entalpie przeniesienia jonu Co(II) i jonu trifluorometanosulfonowego. Wyniki zanalizowano za pomocą teorii solwatacji preferencyjnej. Zmierzono również widma w zakresie widzialnym roztworów jonu Co(II) w mieszaninie DMF-MeOH i zanalizowano je, stosując...
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Optical emission spectroscopy study for nitrogen–acetylene–argon and nitrogen–acetylene–helium 100 kHz and dc discharges
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Detection of the Plant Pathogen Pseudomonas Syringae pv. Lachrymans on Antibody-Modified Gold Electrodes by Electrochemical Impedance Spectroscopy
PublicationThe present work describes an impedimetric immunosensor for Pseudomonas syringae pv. lachrymans (Psl) detection. This pathogen infects many crop species causing considerable yield losses, thus fast and cheap detection method is in high demand. In the assay, the gold disc electrode was modified with 4-aminothiophenol (4-ATP), glutaraldehyde (GA), and anti-Psl antibodies, and free-sites were blocked with bovine serum albumin (BSA)....
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Comparison of near infrared spectroscopy (NIRS) and near-infrared transillumination-backscattering sounding (NIR-T/BSS) methods
PublicationThe aim of the study was to compare simultaneously recorded a NIR-T/BSS and NIRS signals from healthy volunteers. NIR-T/BSS is a device which give an ability to non-invasively detect and monitor changes in the subarachnoid space width (SAS). Experiments were performed on a group of 30 healthy volunteers (28 males and 2 females, age 30.8 ± 13.4 years, BMI = 24.5 ± 2.3 kg/m2). We analysed recorded signals using analysis methods based...
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Use of NMR and Fluorescence Spectroscopy as well as Theoretical Conformational Analysis in Conformation-activity Studies of Cyclic Enkephalin Analogues
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Conformational studies of vasopressin and mesotocin using NMR spectroscopy and molecular modelling methods. Part I: studies in water
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Unique agreement of experimental and computational infrared spectroscopy: a case study of lithium bromide solvation in an important electrochemical solvent
PublicationInfrared (IR) spectroscopy is a widely used and invaluable tool in the studies of solvation phenomena in electrolyte solutions. Using state-of-the-art chemometric analysis of a spectral series measured in a concentration-dependent manner, the spectrum of the solute-affected solvent can be extracted, providing a detailed view of the structural and energetic states of the solvent molecules influenced by the solute. Concurrently,...
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Investigation of the electrochemical behaviour of AA1050 aluminium alloy in aqueous alkaline solutions using Dynamic Electrochemical Impedance Spectroscopy
PublicationThe paper presents the electrochemical behaviour of aluminium alloy AA1050 in aqueous alkaline media in the pH range 14–8.5. Electrochemical study was applied in order to obtain comprehensive information on the mechanism and kinetics of the process of anodic dissolution of aluminium, supplemented by monitoring of surface topography using an electron microscope. The corrosion rate of AA1050 increases with increasing concentration...
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Weak hydrogen bonding interaction S-H···O=C studied by FT-IR spectroscopy and DFT calculations
PublicationInteractions between the thiolate group of tri-tert-butoxysilanethiol (TBST) and carbonyl group of acetone are studied with the use of FT-IR spectroscopy and DFT calculations.