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Badania ramanowskie i mikrotermometria inkluzji a możliwości metodyczne i interpretacyjne

Toboła Tomasz, Jarmołowicz-Szulc Katarzyna

Przegląd Geologiczny

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2023

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Vol. 71, nr 4

235--244

EN

Based on the hitherto existing problems on understanding and interpretation of fluid inclusion microthermometric results and the relatively uncomplicated access to the Raman microspectrometry, both methods have been explained and applied to several samples from the Carpathians and to one sample from a borehole in central Poland (Katarzynin 2). The results of both types of analytical methods are different temperature values of Th – homogenization temperature, Te – eutectic temperature, Tm – ice melting temperature, and the coalification of organic matter (MO). They are interpreted together, which gives a wide range of discussion possibilities significant from the geological point of view.

2

Synthesis and 3D-AFM surface topology of nanographene-like material extracted from sulfonated tri-, di- and monochloroacetic acid

Elsabawy K. M.

Materials Science Poland

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2016

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Vol. 34, No. 3

627--632

EN

In this study a graphene-like material was synthesized by chemical exfoliation of sieved graphite powder with an average particles size ≤100 µm in dispersing medium from tri-, di- and monochloroacetic acid sulfonated with 55 % H2SO3. The results indicated that the yield of graphene-like material was the best in case of trichloroacetic 55 % H2SO3, taking into account structure quality and amount of obtained material. Layered graphene-like material was carefully collected after reduction of GO formed by 50 % dimethylhydrazine. AFM-investigations were performed to characterize nanostructural features of produced graphene and expected surface area which is surface topology dependent. Furthermore, Raman spectra were measured to confirm graphene formation.

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Application of Raman Spectroscopy for Evaluation of Chemical Changes in Dibutyrylchitin Fibres

Biniaś D., Biniaś W., Janicki J.

Fibres & Textiles in Eastern Europe

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2016

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Vol. 24, no. 4 (118)

27--38

EN

Microporous dibutyrylchitin (DBC) fibres formed by means of a dry-wet method were treated with aqueous solutions of potassium hydroxide. By applying various parameters of the alkaline treatment, fibres can be transformed into fibres from regenerated chitin or even into chitosan fibres. In the first stage, with the application of 5% KOH solutions and temperatures ranging from 20 to 90 °C, fibres from regenerated chitin were obtained. The subsequent treatment stage with saturated KOH solutions and the temperature range 70 - 140 °C resulted in obtaining fibres from chitosan with different deacetylation degrees.Structural changes in the fibres occurring in the course of their chemical treatment were analysed using RAMAN spectroscopy. Raman spectra were next mathematically processed by means of GRAMS software within the range 1800 - 820 cm-1 in order to evaluate the changes quantitatively. A new method is described for the determination of butyrylation and deacetylation degrees of dibutyrylchitin, chitin and chitosan. Analysis of the fibres obtained carried out by means of RAMAN spectroscopy proves that in the process gradual degradation of the polymer chains takes place.

PL

Mikroporowate włókna dibutyrylochitynowe otrzymane w wyniku przędzenia metodą sucho mokrą poddano alkalicznym obróbkom przy zastosowaniu roztworów wodorotlenku potasu. W pierwszym etapie uzyskano z włókien dibutyrylochitynowych włókna z chityny regenerowanej przy zastosowaniu 5% roztworów KOH w temperaturach z zakresu 20 – 90 °C. W kolejnym etapie, w wyniku zastosowania nasyconych roztworów KOH w wysokich temperaturach z zakresu 70 – 140 °C, uzyskano włókna chitozanowe o różnicowanych stopniach deacetylacji. Zachodzące w czasie poszczególnych etapów obróbek obserwowano zmiany strukturalne przy zastosowaniu spektroskopii Ramana. W celu przeprowadzenia analizy ilościowej procesów obróbki alkalicznej wykonano rozkłady widm FT Raman przy zastosowaniu oprogramowania „GRAMS” w zakresie 1800-820 cm-1. Na podstawie wykonanych rozkładów widm FT Raman dla badanych serii podjęto próbę obliczenia stopnia butyrylacji oraz stopnia deacetylacji włókien. Na podstawie badań ramanowskich stwierdzono częściową degradację łańcucha polimeru.

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Studies of chrysoprase and microcrystalline silica varieties from serpentinites of Szklary Massif (Foresudetic Block, SW Poland) by Raman spectroscopic technique – preliminary results

Korybska-Sadło I.

Mining Science

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2015

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Vol. 22, Special Issue 2

39--45

EN

The mineralogical properties of green colored chalcedony varieties from weathering cover of slightly serpentinized peridotites (harzburgites) occurring near Szklary village on Foresudetic Block (SW Poland) are studied using Raman spectroscopy in the 200 – 1600-1 wavenumber region . The obtained results show, that in examined samples, the peaks like: 206, 265, 355, 394, 464, 696, 796, 808 cm-1, characteristic for α-quartz were ascertained. In one sample, the characteristic moganite peak (502 cm-1) was found. It implies that presence of other polymorphs of SiO2 in crystalline structure, considered a proof for presence of moganite intergrowths with α-quartz. It indicate, that intensity of green color of measured samples of chrysoprase are not correlated with Raman spectroscopic data. It can be conclude, that examination of Raman spectra can be useful only to recognition of internal phase composition of green cryptocrystalline silica polymorphs occurring in weathering cover of serpentinized peridotites.

5

Synthesis and characterisation of SnO2 films obtained by a wet chemical process

Majumder S.

Materials Science Poland

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2009

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Vol. 27, No. 1

123--129

EN

SnO2 thin films, being n-type semiconductors, have wide application in the field of sensor technology. They are obtained by a wet chemical process, using SnCl2o2H2O as a tin containing precursor. The films thus obtained were subjected to optical, X-ray diffraction (XRD), microstructural, FTIR and Raman studies.

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Raman spectra evaluation of the carbon layers with Voigt profile

Gołąbczak M., Konstantynowicz A.

Journal of Achievements in Materials and Manufacturing Engineering

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2009

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Vol. 37, nr 2

270-276

EN

Purpose: Recent use of Raman spectroscopy as the valuable tool for investigations of the content and state of different material samples is rapidly growing especially in the area of the DLC (Diamond-Like Carbon) layers investigation. Not only qualitative analysis but also quantitative is in the scope of this method which in turn demands use of precise mathematical tools for describing spectrograms. Design/methodology/approach: So-called Voigt profile establish basis for the relatively most precise shape-functions used for describing spectrogram shape. Voigt profile is the convolution of the very well known distribution functions: Gaussian distribution and Cauchy distribution (Lorentz distribution). Gaussian distribution is traditionally recognized as a tool for modeling multi-causal phenomena due to the Central Limit Theorem results. Cauchy distribution is recognized as modeling influence of the Fabry-Pérot interferometer (etalon) used for detection of the Raman spectrum. Findings: We present successful decomposition of the Raman spectra into elements: base function, peaks’ determination and etalon influence on spectral peaks’ shapes. Thorough numerical simulation of the Fabry-Pérot interferometer has been performed and identification of its accuracy parameter has been done when matching Voigt profile based function to the experimental data. Research limitations/implications: Good computational tools for generation of the Voigt profile, being not an analytical function itself and good understanding of mutual relationships between the Voigt profile and the Fabry-Pérot interferometer is of main interest for not only practical but also precise use this tool for quantitative analysis of Raman spectra. Practical implications: The main goal of our work has been the thorough preparation for future works with spectrum deconvolution allowing better resolution in determining Raman spectrum components. Originality/value: So far no proper attention has been paid to precise, quantitative analysis of the Raman spectra of the DLC layers.

7

Characterization of carbon nanotubes by Raman spectroscopy

Costa S., Borowiak-Palen E., Kruszyńska M., Bachmatiuk A., Kaleńczuk R. J.

Materials Science Poland

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2008

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Vol. 26, No. 2

433--441

EN

Application of Raman spectroscopy to analyse carbon nanotubes has been presented. Having a mixture of various carbon nanotube samples, one can easily distinguish, in a quick experiment, presence of singlewalled, doublewalled and multiwalled carbon nanotubes (SWCNT, DWCNT, MWCNT, respectively). The so-called G-line is a characteristic feature of the graphitic layers and corresponds to the tangential vibration of carbon atoms. Another characteristic mode is a typical sign of defective graphitic structures (D-line). A comparison of the intensity ratios of these two peaks gives a measure of the quality of the bulk samples. In addition, there is a third mode, named the radial breathing mode (RBM) which is very sensitive to the diameter of SWCNT and DWCNT. Additional option is application of Raman microscopy for mapping analysis and depth profiling to view the changes of intensity in various directions in the sample.

8

Porous glasses with sodium nitrite impregnations

Rysiakiewicz-Pasek E., Poprawski R., Urbanowicz A., Mączka M.

Optica Applicata

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2005

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Vol. 35, nr 4

769-774

EN

The properties of sodium nitrite introduced in porous glasses have been investigated. SEM graphs indicate existence of sodium nitrite inside glass pores. It has been shown that FTIR and Raman spectra are similar for bulk sodium nitrite and sodium nitrite embedded into porous glass. The nature of FTIR and Raman bands has been determined. The size-effect of sodium nitride introduced into porous glass was observed on the basis of dielectric measurements.

9

Interpretation of Vibrational Spectra of Liquid Water

Chumaevskii N., Rodnikova M. N.

Polish Journal of Chemistry

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2002

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Vol. 76 / nr 9

1363-1370

EN

Based on Raman spectral studies of H2O, D2O, HOD and aqueous solutions of various salts we suggest a new interpretation of vibrational spectra of liquid water. The striking result is obtained that a quite definite set of weak H-bonds corresponds to a quite definite set of the rotational reorientations of the water molecules. The contribution of each orientation depends on the temperature and on the nature of the solved salts.

10

Imaging properties of As₄₀S₄₀Se₂₀ layers

Stronski A. V., Vlcek M.

Opto-Electronics Review

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2000

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Vol. 8, No. 3

263-267

EN

Here we investigate image formation properties of As₄₀S₄₀Se₂₀ layers with regard to their application for gratings fabrication. The light-sensitive properties (photo- and thermally-induced structural changes) of layers have been studied using optical techniques, including Raman spectroscopy. The dissolution kinetics of as - evaporated and exposed layers in amine based etching solutions has been studied. Characteristics of holographic gratings obtained on the base of As₄₀S₄₀Se₂₀ layers are presented.

11

Study of Zn1-xMgxSe and Zn1-xBexSe semiconducting crystals by Raman scattering

Szybowicz M., Kozielski M., Firszt F., Łęgowski S., Męczyńska H., Szatkowski J., Paszkowicz W.

Opto-Electronics Review

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1999

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Vol. 7, No. 2

103-106

EN

Wide gap II-VI mixed crystals containing Mg and Be are recently studied extensively for their application in constructing blue-green laser diodes. This work deals with experimental study of optical modes in Zn1-xMgxSe and Zn1-xBexSe semiconductors using Raman scattering method. Measurements have been performed at room and liquid nitrogen temperatures for Zn1-xMgxSe crystals with Mg content in the range 0 < x < 0,34 and for Zn1-xBexSe with Be content in the range 0 < x 0,26. From polarised Raman spectra the longitudinal (LO) and the transverse (TO) optical mode, corresponding to ZnSe- and MgSe - like modes in Zn1-x MgxSe and to ZnSe- and BeSe - like modes in Zn1-xBexSe, were determined. These lattice vibrations can be described by the modified random element isodisplacement (MREI) model.

12

Raman spectroscopy of the hydrogen bond in the associates H2OxHNO3 and (HNO3)2NO3(-). Evans windows

Potier A., Potier J., Herzog M.H., Herzog J.F.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 2

292-301

EN

The discontinuous shifts of Raman lines with the concentration between 500 and 2600 cm(-1) in solutions of HNO3-H2O and KNO3-HNO3 show the formation of the associates H2OxHNO3 and (HNO3)2xNO3(-). The study of the 2000-3600 cm(-1) range enhances the complexity of the OH' spectra with the occurrence of Evans windows, owing to the formation of hydrogen bonds in the two associates.