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wszystkich: 382
wybranych: 343
Wyniki wyszukiwania dla: RAMAN
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Detection of Denatonium Benzoate (Bitrex) Remnants in Noncommercial Alcoholic Beverages by Raman Spectroscopy
PublikacjaIllegal 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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Colored Tattoo Ink Screening Method with Optical Tissue Phantoms and Raman Spectroscopy
PublikacjaDue 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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Self-healing mechanism of metallopolymers investigated by QM/MM simulations and Raman spectroscopy
PublikacjaThe 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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Resonance-Raman spectro-electrochemistry of intermediates in molecular artificial photosynthesis of bimetallic complexes
PublikacjaThe sequential order of photoinduced charge transfer processes and accompanying structure changes were analyzed by UV-vis and resonance-Raman spectroscopy of intermediates of a Ru(II) based photocatalytic hydrogen evolving system obtained by electrochemical reduction.
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DETERMINATION OF SP3 FRACTION IN ta-C COATING USING XPS AND RAMAN SPECTROSCOPY
PublikacjaThe paper presents results of studies on the structure of tetrahedral amorphous carbon films (ta-C) with a thickness in the range from 20 to 280 nm, deposited using pulsed vacuum arc technique with an electromagnetic Venetian blind plasma filter. The results of the phase structure analysis, obtained using visible Raman spectroscopy and UV Raman spectroscopy methods, showed a strong dependence of the results on the presence, on...
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Ultrastructural analysis of the submandibular sialoliths: Raman spectroscopy and electron back-scatter studies
PublikacjaThe 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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FTIR, Raman spectroscopy and HT-XRD in compatibility study between naproxen and excipients
PublikacjaDetection of incompatibility between an active pharmaceutical ingredient (API) and excipients, including the selection of the most biopharmaceutical advantageous excipients is extremely important in the pre-formulation process of developing a solid dosage form technology. Therefore, having fast and reliable methods for identifying incompatibility is fundamental in pharmaceutical technology. For this purpose, combined Fourier transform...
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Theoretical Assessment of Excited State Gradients and Resonance Raman Intensities for the Azobenzene Molecule
PublikacjaThe ground state geometries and vibrational frequencies as well as the excitation energies and excited state gradients of the S 1(nπ*) and S 2(ππ * ) states of trans - and cis -azobenzene are investigated by several DFT methods, namely B3LYP, PBE, M06-2X, CAM-B3LYP, and ω B97X. Excited state properties and in particular gradients are also assessed using the wave function based methods EOM-CCSD and RASPT2/RASSCF. Comparison with...
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Polyurethane Nanocomposites Containing Reduced Graphene Oxide, FTIR, Raman, and XRD Studies
PublikacjaRecently, graphene and other graphene-based materials have become an essential part of composite science and technology. Their unique properties are not only restricted to graphene but also shared with derivative compounds like graphene oxide, reduced graphene oxide, functionalized graphene, and so forth. One of the most structurally important materials, graphene oxide (GO), is prepared by the oxidation of graphite. Though removal...
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FT-Raman Spectroscopy as a Tool to Study the Secondary Structures of Wheat Gliadin Proteins
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Raman and infrared investigation of ferroelectric ceramics. IV Workshop on Atomic and Molecular Physics.
PublikacjaZastosowano spektroskopię absorbcyjną w podczerwieni i spektroskopię Ramana do badania ceramik ferroelektrycznych o kompozycji Ba(Ti1-xZrx)O3. Ceramiki te charakteryzują się możliwością przestrajania przenikalności elektrycznej za pomocą pola elektrycznego.
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Raman investigation of the patina layers on Hungarian copper ingots from a fifteenth century shipwreck
PublikacjaWe report results of the patina study of underwater archeological finding ofmedieval copper objects performed by means of the Raman and complementary spectroscopic techniques. The objects were found submerged in the sea as cargo part of the ship which sunk in the Gulf of Gdańsk in 1408. The excavated collection consists of 230 oval ingots of the size and mass up to about 60 cm and 18 kg (total of 2 tons), respectively. In the Raman...
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Towards spectroscopic monitoring of photoelectrodes: In-situ Raman photoelectrochemistry of a TiO2/prussian blue photoanode
PublikacjaHere, novel in-situ Raman photoelectrochemical measurements are performed. The obtained results have proved that it is possible to track the progress of a photoelectrochemical reaction that takes place on a semiconducting electrode using the spectroscopic method. As an exemplary system, the Ti/TiO2/Prussian blue electrode is investigated. Since TiO2 is an n-type semiconductor, it cannot act as an efficient anode in dark conditions....
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Drop-coating deposition surface-enhanced Raman spectroscopy on silver substrates for biofluid analysis
PublikacjaUtilization of surface-enhanced Raman spectroscopy as a measurement technique is of particular interest in biodetection due to its superb chemical specificity and high sensitivity. The use of SERS substrates further improve this method by massive enhancement of the molecule Raman spectrum, permitting very low levels of detection. Therefore it is important to seek for new ways to develop reliable substrates, which are quickly and...
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Study of the NO2 sensing mechanism of PEDOT-RGO film using in situ Raman Spectroscopy
PublikacjaIn this work, the mechanism of the NO2 reaction with PEDOT-RGO composite film has been investigated via in situ Raman spectroscopy. Reduced graphene oxide (RGO), poly(3,4-ethylenedioxytiophene)-reduced graphene oxide (PEDOT-RGO) and poly(3,4-ethylenedioxytiophene)/ClO4− (PEDOT/ClO4−) films were fabricated using an electrodeposition method and used as resistance sensors of gaseous nitrogen dioxide. The experimental results indicate...
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Optimization of Polycrystalline CVD Diamond Seeding with the Use of sp³/sp² Raman Band Ratio
PublikacjaThe influence of various nanodiamond colloids used for seeding nondiamond substrates in microwave plasma enhanced chemical vapour deposition diamond process was investigated. Colloids based on deionized water, isopropanol alcohol and dimethyl sulfoxide (DMSO) were used with different grain size dispersion: 150, 400 and 35 nm, respectively. The influence of growth time was also taken into consideration and bias enhanced nucleation....
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Single‐walled carbon nanotubes modified by PFO: An optical absorption and Raman spectroscopic investigation
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Characterization of nano-silica vegetable grease with diffusing wave spectroscopy DWS and Raman spectroscopy
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Raman diagnostics in manufacturing of polymer planar optical waveguides. Optical Fibers and Their Applications VIII.
PublikacjaZastosowano spektroskopię ramanowską do diagnostyki procesu syntezy nowego typu materiałów cienkowarstwowych polimerów hybrydowych, przeznaczonych do wytwarzania światłowodów planarnych. Zbadano poprawność poszczególnych etapów procesu technologicznego oraz strukturę molekularną materiału. Zademonstrowano możliwość kontroli procesu technologicznego w czasie rzeczywistym.
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EXAMINATION OF SOL-GEL DERIVED HYDROXYAPATITE ENHANCED WITH SILVER NANOPARTICLES USING OCT AND RAMAN SPECTROSCOPY
PublikacjaHydroxyapatite (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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Discrimination of Apple Liqueurs (Nalewka) Using a Voltammetric Electronic Tongue, UV-Vis and Raman Spectroscopy
PublikacjaThe 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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Influence of silver-core gold-shell nanoparticle parameters on the variation of surface-enhanced Raman spectra
PublikacjaThe detection of molecules by surface-enhanced Raman spectroscopy (SERS) is dependent on the nanomaterial used to induce the enhancement effect. This depends on a variety of parameters of the substrate such as the metal used for their creation, their shape, size and size distribution, concentration, as well as the parameters of the solution, such as packing of the nanoparticles, the complexity of the sample, the solvent, etc. It...
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Analysis of friction ridge evidence for trace amounts of paracetamol in various pharmaceutical industries by Raman spectroscopy
PublikacjaThe 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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A Novel Ru(II) Polypyridine Black Dye Investigated by Resonance Raman Spectroscopy and TDDFT Calculations
PublikacjaThe optical properties of a new(bipyridine)2Ru(4H-imidazole) complex presenting a remarkablebroad absorption in the visible range are investigated. Thestrong overlap of the absorption with the solar radiationspectrum renders the studied complex promising as a blackabsorber and hence as a starting structure for applications inthe field of dye-sensitized solar cells. The correlations betweenstructural and electronic features for...
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Ex situ XANES, XPS and Raman studies of poly(3,4-ethylenedioxythiophene)modified by iron hexacyanoferrate
PublikacjaPraca dotyczy badań XANES, XPS i Ramana polimeru przewodzącego poli(3,4-etylenodioksytiofenu) modyfikowanego heksacyjanożelazianem żelaza. Badania XANES potwierdziły oktaedryczne otoczenie atomu żelaza, którego najbliższymi sąsiadami są atomy węgla oraz atomy azotu. Badania XPS wykazały istnienie wiązań Fe-C, Fe-N oraz chemicznego oddziaływania między atomem siarki polimeru a atomem żelaza błękitu pruskiego. Obecność oddziaływań...
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Ex situ XANES, XPS and Raman studies of poly(3,4-ethylenedioxythiophene) modified by iron hexacyanoferrate
PublikacjaPraca dotyczy materiału hybrydowego złożonego z polimeru elektroaktywnego poli(3,4-etylenodioksytiofenu) i Błękitu Pruskiego. Wykonano pomiary spektroskopowe z użyciem technik: spektrometrii fotoelektronów wzbudzonych promieniami X (X-ray Photoelectron Spectroscopy (XPS)), spektroskopii absorpcyjnej struktury przykrawędziowej (X-ray Absorption Near Edge Structure (XANES)) oraz spektroskopii mikro-Ramana. Przeprowadzone badania...
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The Use of Raman Spectroscopy to Monitor Changes in the Intensity of Ratio of Integral Unsaturated Bands in Bio-Greases
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Combined analysis of whole human blood parameters by Raman spectroscopy and spectral-domain low-coherence interferometry
PublikacjaIn 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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An Assessment of RASSCF and TDDFT Energies and Gradients on an Organic Donor−Acceptor Dye Assisted by Resonance Raman Spectroscopy
PublikacjaThe 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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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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Application of Raman Spectroscopy to Evaluate the Structure Changes of Lubricating Grease Modified with Montmorillonite after Tribological Tests
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Raman investigation of minor component reaction during polymer synthesisprocess. IV Workshop on Atomic and Molecular Physics.
PublikacjaWykonano badania ramanowskie reakcji zachodzących podczas procesu wytwarzania polimerów hybrydowych w ich części organicznej. Optyczne monitorowanie przebiegu reakcji w czasie rzeczywistym umożliwiło zbadanie ich efektywności oraz czasu trwania. Wyjaśniono też rolę katalizatorów.
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Sensing the onset of epoxy coating degradation with combined Raman spectroscopy/atomic force microscopy/electrochemical impedance spectroscopy
PublikacjaThe paper presents the results of investigation on epoxy resin durability upon 12-week exposure to UV radiation. The aim was early determination of the onset of epoxy degradation and for this purpose an epoxy film on steel substrate systems were periodically inspected using Raman spectroscopy, atomic force microscopy and electrochemical impedance spectroscopy. The behaviour of examined polymer could be divided into three periods: immunity,...
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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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Ab initio study of phenyl benzoate: structure, conformational analysis, dipole moment, IR and Raman vibrational spectra
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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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Using isothermal calorimetry and FT-Raman spectroscopy for step-by-step monitoring of maize seed germination: case study
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Raman scattering measurements in monitoring of polymer synthesis process. Lightmetry 2002 : Metrology and Testing Techniques Using Light.
PublikacjaW artykule omówiono możliwości wykorzystania pomiarów ramanowskich do monitorowania w czasie rzeczywistym przebiegu procesów syntezy materiałów polimerowych. Wykorzystano sondy światłowodowe do sprzęgnięcia aparatury pomiarowej z typowym stanowiskiem technologicznym. Pomiary miały charakter zdalny, nieniszczący i niezakłócający przebieg reakcji.
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Sum-over-state expressions including second-order Herzberg–Teller effects for the calculation of absorption and resonance Raman intensities
PublikacjaThe sum-over-state expressions are derived to calculate the second-order Herzberg–Teller (HT) effects in absorption and resonance Raman spectroscopies. These effects depend on the second derivatives of the transition dipole moment with respect to the vibrational coordinates. The method is applied to the molecule of 1,3-butadiene using density functional theory calculations. It is found that the second-order HT effects are significant...
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The role of Herzberg-Teller effects on the resonance Raman spectrum of trans-porphycene investigated by time dependent density functional theory.
PublikacjaThe S1 excited state properties as well as the associated absorption and resonance Raman (RR) spectra of trans-porphycene are investigated by means of time dependent density functional theory calculations. The relative magnitude of the Franck-Condon (FC) contribution and of the Herzberg-Teller (HT) effects is evaluated for both the absorption and RR intensities. The accuracy of the calculated spectra is assessed by employing different...
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Long-working-distance Raman system for monitoring of uPA ECR CVD process of thin diamond/DLC layers growth
PublikacjaW artykule przedstawiono konstrucję systemu optoelektronicznego do monitoringu ramanowskiego in-situ procesu μPA ECR CVD (ang.: Microwave Plasma Assisted Electron Cyclotron Resonance Chemical Vapour Deposition), stosowanego do osadzania cienkich warstw diamentowych i diamentopodobnych DLC. System ma budowę modułową i wyposażony jest w dedykowane sondy optyczne. Przedstawiono wyniki pomiarów testowych, potwierdzjące, że system posiada...
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On Raman optical activity sign-switching between the ground and excited states leading to an unusual resonance ROA induced chirality
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IR–Raman, NMR and density functional methods in the examination of tautomerism and features of N-methyl substituted 9-acridinamine derivatives
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Corrosion Inhibition of Aluminium Alloy AA6063-T5 by Vanadates: Local Surface Chemical Events Elucidated by Confocal Raman Micro-Spectroscopy
PublikacjaChemical interactions between aqueous vanadium species and aluminium alloy AA6063-T5 were investigated in vanadate-containing NaCl solutions. Confocal Raman and X-ray photoelectron spectroscopy experiments were utilised to gain insight into the mechanism of corrosion inhibition by vanadates. A greenish-grey coloured surface layer, consisting of V+4 and V+5 polymerized species, was seen to form on the alloy surface, especially on...
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Comparison of simplified sum-over-state expressions to calculate resonance Raman intensities including Franck-Condon and Herzberg-Teller effects
PublikacjaSum-over-state (SOS) expressions to simulate absorption spectroscopy and resonance Raman (RR) scattering including Franck-Condon (FC) and Herzberg-Teller (HT) effects are described. Starting from the general SOS method, several simplified SOS formulae are derived. In particular, within the so-called independent mode displaced harmonic oscillator model, it is shown that including the vibronic structure in the absorption and RR spectra...
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Assessment of the structural evolution of polyimide-derived carbons obtained by phosphoric acid activation using Fourier transform infrared and Raman spectroscopy
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X-ray photoelectron spectroscopy, Raman and photoluminescence studies on formation of defects in Cu:ZnO thin films and its role in nonlinear optical features
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The influence of polarization of titania nanotubes modified by a hybrid system made of a conducting polymer PEDOT and Prussian Blue redox network on the Raman spectroscopy response and photoelectrochemical properties
PublikacjaIn this work we show the impact of applied potential on network vibrations and photoelectrochemical properties of a composite material containing hydrogenated titania nanotubes and poly (3,4-ethylenedioxythiophene) with iron hexacyanoferrate (H-TiO2/pEDOT:Fehcf) acting as a redox centre. For this purpose, Raman spectroscopy measurements under the working electrode (WE) polarization were carried out, allowing investigation of changes...
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Application of Alanine Scanning to Determination of Amino Acids Essential for Peptide Adsorption at the Solid/Solution Interface and Binding to the Receptor: Surface-Enhanced Raman/Infrared Spectroscopy versus Bioactivity Assays
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Micro-Raman spectroscopy in the studies of multiphase separated polyurethanes. [online] W: [Proc.] UTECH Europe 2003 . The International Polyurethane Industry Conference and Exhibition. 25/26/27 March 2003, The Hague, Netherlands. London: Crain Communications Ltd. Dostępny w World Wide Web: http://UTECH-2003.com + wydruk.**2003 [s. 123-130 bibliogr. 41 poz.]Mikro-Ramanowska spektroskopia w badaniach poliuretanów wykazujących separację wielofazową.
PublikacjaPrzedmiotem badań były trzy próbki poliuretanowe o zawartości 30% segmentówsztywnych otrzymanych z politlenku propylenu, diizocyjanianu difenylometanui butanodiolu. Próbki te wykazują morfologię wielofazową, w której można wy-różnić globule i sferolity rozproszone w matrycy polimerowej.Za pomocą spek-troskopii mikro-Ramana przeprowadzono mikroanalizę chemiczną wszystkich ele-mentów morfologicznych. Stwierdzono odmienny skład...