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Search results for: UV-Vis spectroscopy
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Investigation of morphological and electrical properties of the PMMA coating upon exposure to UV irradiation based on AFM studies
PublicationCelem badania było określenie wpływu promieniowania ultrafioletowego na morfologię powierzchni powłoki i na jej właściwości elektryczne. Cienka powłoka z polimetakrylanu metylu została nałożona na podłoże stalowe metodą zanurzeniową. Oceny stanu przed ekspozycją UV i w jej trakcie dokonywano przy użyciu mikroskopu sił atomowych. Na obrazach AFM zaobserwowano pojawienie się mikropęknięć. Celem zweryfikowania czy wykryte nieciągłości...
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CE-UV method for the determination of catecholamine metabolites from baby pee-covered diapers
PublicationA method has been developed for the analysis of vanillylmandelic acid, homovanillic acid, and 5-hydroxyindoleacetic acid from baby urine as biomarkers of neuroblastoma in infants. Disposable diapers were employed as sampling devices in order to guarantee a low invasiveness during this step. The proposed method consists on a simple extraction step with water from the used diaper followed by the measurement using capillary electrophoresis...
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Simultaneous Determination of Indolic Compounds in Plant Extracts by Solid-Phase Extraction and High-Performance Liquid Chromatography with UV and Fluorescence Detection
PublicationA high-performance liquid chromatographic method with UV and fluorescence detection (HPLC-DAD-FLD) was developed for simultaneous determination of indolic compounds in plant material. Indole-3-carbinol (I3C), indole-3-acetic acid (I3AA), indole-3-acetonitrile (I3ACN), and 3,3′-diindolylmethane (DIM) were used as representative compounds that cover a wide spectrum of indole structures occurring in nature. For concentration and purification...
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X-ray Photoelectron Spectroscopy of Carboxylic Acids as Corrosion Inhibitors of Aluminium Alloys
PublicationThe datasets, titled X-ray Photoelectron Spectroscopy studies of citric acid adsorption on aluminium alloy 5754 in alkaline media and X-ray Photoelectron Spectroscopy studies of various carboxylic acids adsorption on aluminium alloys in alkaline media, contain XPS studies of the corrosion inhibitory action of selected dicarboxylic acids towards commercially available aluminium alloy 5754 in alkaline media at pH=11. These datasets...
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Characterization of nano-silica vegetable grease with diffusing wave spectroscopy DWS and Raman spectroscopy
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Utilizing pulse dynamics for non-invasive Raman spectroscopy of blood analytes
PublicationNon-invasive measurement methods offer great benefits in the field of medical diagnostics with molecular-specific techniques such as Raman spectroscopy which is increasingly being used for quantitative measurements of tissue biochemistry in vivo. However, some important challenges still remain for label-free optical spectroscopy to be incorporated into the clinical laboratory for routine testing. In particular, non-analyte-specific...
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Organic Vapor Sensing Mechanisms by Large-Area Graphene Back-Gated Field-Effect Transistors under UV Irradiation
PublicationThe gas sensing properties of graphene back-gated field-effect transistor (GFET) sensors toward acetonitrile, tetrahydrofuran, and chloroform vapors were investigated with the focus on unfolding possible gas detection mechanisms. The FET configuration of the sensor device enabled gate voltage tuning for enhanced measurements of changes in DC electrical characteristics. Electrical measurements were combined with a fluctuation-enhanced...
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Non-invasive blood glucose monitoring with Raman spectroscopy: prospects for device miniaturization
PublicationThe number of patients with diabetes has reached over 350 million, and still continues to increase. The need for regular blood glucose monitoring sparks the interest in the development of modern detection technologies. One of those methods, which allows for noninvasive measurements, is Raman spectroscopy. The ability of infrared light to penetrate deep into tissues allows for obtaining measurements through the skin without its...
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Characterization of metabolites in different kiwifruit varieties by NMR and fluorescence spectroscopy
PublicationIt is known from our previous studies that kiwifruits, which are used in common human diet, have preventive properties of coronary artery disease. This study describes a combination of 1H NMR spectroscopy, multivariate data analyses and fluorescence measurements in differentiating of some kiwifruit varieties, their quenching and antioxidant properties. A total of 41 metabolites were identified by comparing with literature data...
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Local impedance spectroscopy of membranes
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Advances in Atomic and Molecular Spectroscopy
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Local impedance spectroscopy of membranes
PublicationCelem niniejszej publikacji jest zaprezentowanie zastosowania techniki Lokalnej Elektrochemicznej Spektroskopii Impedancyjnej (LEIS) do uzyskania lokalnej charakterystyki membran. Membranę wykonaną z polichlorku winylu (PCV), plastyfikowaną sebacynianem bis(2etyloheksylu) i domieszkowaną boranem tetradodecyloamoniowym zbadano pod kątem równomiernego rozkładu przewodnictwa na powierzchni badanej próbki. Lokalne pomiary impedancyjne,...
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The Microwave Sources for EPR Spectroscopy
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The gyrotron source for the EPR spectroscopy
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Correction methods in impedance spectroscopy
PublicationW pracy przedstawiono trzy grupy metod, ktÓre mogą być zastosowane do korekcji danych pomiarowych uzyskanych za pomoca spektroskopii impedancyjnej.
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Remote Monitoring System for Impedance Spectroscopy using Wireless Sensor Network
PublicationThe architecture of a miniaturized impedanceanalyser with wireless communication module for remoteImpedance Spectroscopy (IS) of anticorrosion coatings ondifficult-to-reach objects (e.g. on the steel construction ofthe bridge) is described in this paper. Some practical aspectsof implementation of a Wireless Sensor Network (WSN) arealso discussed. A low scale, middle range, WSN networkcomposed of a Base Station (BS) with a Personal...
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Synthesis and properties of UV-curable poly(imideurethane) acrylates.
PublicationOtrzymano światłoczułe poli(imidouretano) akrylany (PIUA) które użyte zostały do wytwarzania światłoczułych kompozycji z dodatkiem reaktywnych rozcieńczalników i różnych fotoinicjatorów. Uzyskane z nich cienkie warstwy polimerowe ulegały usieciowaniu pod działaniem światłaUV w ciągu 10-30 sek. W badaniach fotolitograficznych uzyskano z ich użyciem ścieżki izolacyjne o rozdzielczości 10 mikrometrów. Usieciowane PIUA scharakteryzowano...
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Electron impact fragmentation of pyrrole molecules studied by fluorescence emission spectroscopy
PublicationThe fluorescence emission spectroscopy using electron impact excitation technique was employed to study fragmentation processes of the gas phase pyrrole molecules. The following excited fragmentation species were observed by detection of their fluorescence decay: the atomic hydrogen H(n), n = 4-7 and the diatomic CH(A2Δ), CN(B2Σ+), NH(A3Π) and C2(d3Πg) fragments. These atomic and molecular products differ from those previously...
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Detection of Denatonium Benzoate (Bitrex) Remnants in Noncommercial Alcoholic Beverages by Raman Spectroscopy
PublicationIllegal alcoholic beverages are often introduced into market using cheap technical alcohol, which is contaminated by denatonium benzoate (Bitrex) of very small concentration. Bitrex is the most bitter chemical compound and has to be removed before alcohol consumption. The home-made methods utilize sodium hypochlorite to disintegrate particles of denatonium benzoate in alcohol and to remove bitter taste before trading. In this experimental...
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Local electrochemical impedance spectroscopy in dynamic mode of galvanic coupling
PublicationA novel method that combines local electrochemical impedance spectroscopy and mapping in dynamicmode is proposed. Method was validated over two galvanic couplings, namely zinc/copper and cad-mium/copper. Impedance spectrum response for all measuring points was obtained by means ofsimultaneous implementation of selected range of frequencies. Proposed method allows the measure-ment in a more time-efficient manner, at the same time...
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The influence of the size of a one-faced metallic head in Janus nanoparticles as a co-catalyst on the photocatalytic efficiency of hydrogen evolution under vis light irradiation
PublicationJanus nanoparticles (NPs) consisting of MoOxSy nanospheres and silver (Ag) head, successfully developed by a simple, controlled method were in the first time they were applied as a co-catalysts in photocatalytic hydrogen generation reaction under vis light irradiation (λ > 420 nm). The MoOxSy-Ag as a co-catalysts were deposited on the obtained ZnIn2S4 microspheres (ZIS) using physical absorption method. The influence of the size...
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Ultrastructural analysis of the submandibular sialoliths: Raman spectroscopy and electron back-scatter studies
PublicationThe aim of work was the epidemiological analysis of the occurrence of sialolithiasis of the submandibular gland in adults and the evaluation of the ultrastructure of salivary stones. The study sample consisted of 44 sialoliths. Analysis of the structure and chemical composition of sialoliths was performed using a Scanning Electron Microscope and Raman Spectroscopy. Comparing our results with the literature we can say that the epidemiology...
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Design and Microwave-Assisted Synthesis of TiO2-Lanthanides Systems and Evaluation of Photocatalytic Activity under UV-LED Light Irradiation
PublicationThe TiO2-Eu and TiO2-La systems were successfully synthesized using the microwave method. Based on the results of X-ray diffraction analysis, it was found that regardless of the analyzed systems, two crystal structures were noted for the obtained samples: anatase and rutile. The analysis, such as XPS and EDS, proved that the doped lanthanum and europium nano-particles are present only on the TiO2 surface without disturbing the...
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Combined chemoresistive and in situ FTIR spectroscopy study of nanoporous NiO films for light-activated nitrogen dioxide and acetone gas sensing
PublicationThe chemoresistive sensor response of nanoporous NiO films prepared by advanced gas deposition was investigated by combined resistivity and in situ FTIR spectroscopy, with and without simultaneous light illumination, to detect NO2 and acetone gases. The sensitivity towards NO2 increased dramatically under UV irradiation employing 275 nm light. Improved sensitivity was observed at an elevated temperature of 150 °C. In situ FTIR...
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Colored Tattoo Ink Screening Method with Optical Tissue Phantoms and Raman Spectroscopy
PublicationDue to the increasing popularity of tattoos among the general population, to ensure their safety and quality, there is a need to develop reliable and rapid methods for the analysis of the composition of tattoo inks, both in the ink itself and in already existing tattoos. This paper presents the possibility of using Raman spectroscopy to examine tattoo inks in biological materials. We have developed optical tissue phantoms mimicking...
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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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Self-healing mechanism of metallopolymers investigated by QM/MM simulations and Raman spectroscopy
PublicationThe thermally induced self-healing mechanisms in metallopolymers based on bisterpyridine complexes of iron(II) sulfate and cadmium(II) bromide, respectively, were studied by means of combined quantum mechanical/molecular mechanical (QM/MM) simulations and Raman spectroscopy. Two possible healing schemes, one based on a decomplexation of the cross-linking complexes and a second one relying on the dissociation of ionic clusters,...
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Determination of pitting corrosion stage of stainless steel by galvanodynamic impedance spectroscopy
PublicationThis paper investigates the methodology for differentiation of multistep process of pitting corrosion of AISI 304 stainless steel in the environment of iron (III) chloride. Measurements were performed using Galvanodynamic Electrochemical Impedance Spectroscopy (GDEIS). Application of this methodology allowed monitoring of natural corrosion process without external current (IDC = 0A) nor potential perturbation of the system. Applied...
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Mono- and bi-metallic plasmonic photocatalysts for degradation of organic compounds under UV and visible light irradiation
PublicationTitania powders were surface modified with gold and/or silver nanoparticles (NPs) by photodeposition method. Gold modified titania exhibited much higher photocatalytic activity during methanol dehydrogenation under UV irradiation than titania modified with monometallic silver and bimetallic Au–Ag NPs. Bimetallic photocatalysts exhibited either enhanced or reduced visible light activity, depending on properties of noble metal NPs,...
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Effects of Post-Harvest Elicitor Treatments with Ultrasound, UV- and Photosynthetic Active Radiation on Polyphenols, Glucosinolates and Antioxidant Activity in a Waste Fraction of White Cabbage (Brassica oleracea var. capitata)
PublicationBiosynthesis of phytochemicals in leaves of Brassica can be initiated by abiotic factors. The aim of the study was to investigate elicitor treatments to add value to waste of cabbage. A leaf waste fraction from industrial trimming of head cabbage was exposed to UV radiation (250–400 nm, 59 and 99 kJ m-2, respectively), photosynthetic active radiation (PAR, 400–700 nm, 497 kJ m-2), and ultrasound in water bath (35 kHz, at 15, 30...
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Anharmonic Infrared Spectroscopy through the Fourier Transform of Time Correlation Function Formalism in ONETEP
PublicationDensity functional theory molecular dynamics (DFT-MD) provides an efficient framework for accurately computing several types of spectra. The major benefit of DFTMD approaches lies in the ability to naturally take into account the effects of temperature and anharmonicity, without having to introduce any ad hoc or a posteriori corrections. Consequently, computational spectroscopy based on DFT-MD approaches plays a pivotal role in...
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GEM-based gaseous photomultipliers for UV and visible photon imaging
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Is Mc1r an important regulator of non-pigmentary responses to UV radiation?
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UV-crosslinkable photoreactive self-adhesive hydrogels based on acrylics
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Toxicity of aqueous mixture of phenol and chlorophenols upon photosensitized oxidation initiated by sunlight or vis-lamp
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Analyzer for spectroscopy of low-impedance objects
PublicationW artykule przedstawiono analizator umożliwiający pomiar impedancji w zakresie 1 ohma < |Zx| < 100 Mohma. Zastosowano w nim nowe rozwiązania dotyczące obwodu wejściowego i techniki detekcji fazoczułej sygnałów pomiarowych. Obwód wejściowy zaprojektowano w postaci 5-zaciskowej sondy pomiarowej, która umożliwia ograniczenie wpływu rezystancji, indukcyjności i pojemności pasożytniczych na błąd pomiaru impedancji w szerokim przedziale...
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Saturation ESR spectroscopy of PA12 polyamide
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Application of NIR and Raman Spectroscopy in Biotechnology
PublicationStudium Press LLC, U.S.A.
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Integrating Optical Spectroscopy and Chemometric Methods
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Impedance spectroscopy of undoped cerium oxide.
PublicationW pracy przedstawiono badania impedancyjne niedomieszkowanego tlenku ceru. Wyniki wskazują na występowanie zjawiska dyfuzji,???? które nie są (.. jest.?)związane z odpowiedzią elektrodową. Rozważania teoretyczne dopuszczają obserwowanie impedancji Warburga, która reprezentuje zjawisko dyfuzji w przewodnikach mieszanych, jednakże niewiele informacji na ten temat można znaleźć w literaturze. W związku z tym szczegółowe badania zródła...
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Raman spectroscopy in investigation of rheometric processes
PublicationPraca porusza problem analizy cienkiej warstwy przyściennej -oleju za pomocą spektroskopii ramanowskiej. Parametry (grubość, struktura chemiczna) cienkiej warstwy przyśniennej są istotną informacją do oceny przebiegu procesu wyciskania past modelowych. Zaprezentowano wyniki pomiarów oraz konstrukcje ramanowskich układów pomiarowych.
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Raman spectroscopy in investigation of rheometric processes
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Impedance spectroscopy of single chamber SOFC.
PublicationMechanizm działania jednokomorowego ogniwa paliwowego SOFC, które pracuje w mieszaninie powietrza i paliwa, nie jest do końca zbadany. W tej pracy przedstawiono wyniki badań ogniwa paliwowego zbudowanego z tlenku cyrkonu stabilizowanego itrem jako nośnego elektrolitu, cermetu z tlenku niklu jako anody i perovskitu LSCF jako katody w temperaturach 500-700C z użyciem mieszaniny propanu i powietrza. Wykorzystując spektroskopię impedancyjną...
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Time-of-flight spectroscopy for medical applications.
PublicationW pracy przedstawiono korzyści optycznej spektroskopii czasu przelotu, w zastosowaniach medycznych. Przedstawiono także zasadę pomiarów oraz pokazano, jak z danych pomiarowych można wyznaczyć podstawowe parametry optyczne tkanki. Potencjał pomiarowy optycznej spektroskopii czasu przelotu zaprezentowano na przykładzie pomiarów ośrodków silnie rozpraszających światło jakimi są: papier, cicze technologiczne z papierni, wodne roztwory...
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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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Application of quartz crystal microbalance and dynamic impedance spectroscopy to the study of copper corrosion inhibitors
PublicationThe study investigates the application of Dynamic Electrochemical Impedance Spectroscopy (DEIS) and Electrochemical Quartz Crystal Microbalance (EQCM) techniques to examine the corrosion inhibition of copper by Benzotriazole and Sodium Folate in a 0.1 M NaCl solution. DEIS, an advanced version of Electrochemical Impedance Spectroscopy (EIS), allows for real-time monitoring of non-stationary electrochemical systems,...
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Application of Galvanostatic Non-Linear Impedance Spectroscopy to the Analysis of Metallic Material Degradation
PublicationThis study presents a novel application of Non-Linear Electrochemical Impedance Spectroscopy (NLEIS) in galvanostatic mode for the rapid, non-destructive assessment of metal degradation. By using galvanostatic mode instead of traditional potentiostatic methods, polarization-related challenges are mitigated, enabling more accurate and reliable analysis. The technique allows for the determination of corrosion rates (corrosion current)...
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Dielectric Spectroscopy Studies and Modelling of Piezoelectric Properties of Multiferroic Ceramics
PublicationCompounds 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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The Optical Coherence Tomography and Raman Spectroscopy for Sensing of the Bone Demineralization Process
PublicationThe presented research was intended to seek new optical methods to investigate the demineralization process of bones. Optical examination of the bone condition could facilitate clinical trials and improve the safety of patients. The authors used a set of complementary methods: polarization-sensitive optical coherence tomography (PS-OCT) and Raman spectroscopy. Chicken bone samples were used in this research. To stimulate in laboratory...
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Mössbauer Spectroscopy and Magnetoelectric Effect Studies of Multiferroic Ceramics Based on BiFeO<sub>3</sub>
PublicationIn this work the results of investigations for (BiFeO3)x(BaTiO3)1-x and Bi1-xNdxFeO3 solid solutions are described. Samples were prepared by the conventional solid-state sintering method. X-ray diffraction, 57Fe Mössbauer spectroscopy, and magnetoelectric effect measurements were applied as complementary methods to determine the structure and magnetic properties of materials. For (BiFeO3)x(BaTiO3)1-x solid solutions Mössbauer...