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1

Evaluation of changes caused by HR-HPV infection in squamous cell carcinoma of the head and neck using Raman microspectroscopy in combination with multivariate statistical analysis

Szurko Agnieszka, Zygadło Dorota, Student Sebastian, Śnietura Mirosław, Lorenc Zbigniew, Kiełboń Agnieszka, Waniczek Dariusz

Polish Journal of Medical Physics and Engineering

|

2024

|

Vol. 30, Iss. 2

69--78

EN

Introduction: Squamous cell carcinoma of the head and neck region (HNSCC), with a positive status for high oncogenic potential human papillomavirus (HR-HPV), represents a clinically distinct disease entity compared to HPV-independent cases. Patients exhibit variations in prognosis and proposed therapy regimens. A prompt and reliable diagnosis of the presence of HPV infection could optimize the treatment for these patients. Currently employed treatment methods are long-term, expensive, and lack specificity, especially when administered separately. Material and methods: The research objective of this study is to explore significant differences in the Raman spectra of biological samples taken from patients with HNSCC, facilitating the confirmation of HPV virus presence. Study groups were delineated based on histopathological diagnosis and molecular biology tests, confirming the biological activity of the virus and the presence of the HR-HPV form with a diagnosis of a specific subtype. Results: To identify high oncogenic potential human papillomavirus (HR-HPV) infection as a crucial factor in squamous cell carcinoma of the head and neck region, an effective automatic data analysis system was established, relying on Raman microspectroscopy and multivariate analysis. Our results showed clear ranges of the Raman spectrum that differentiated between HPV-associated and non-HPV-associated cancers. Conclusions: In conclusion, our experience shows a great diagnostic potential of Raman confocal microscopy with multidimensional statistical analysis. In the future, the use of this method may allow for the creation of an effective and automated HR-HPV detection system in neoplastic tissue.

2

Structural, morphological and photoluminescent properties of Nd-coated silicon nanostructures

Mefoued Amine, Mahmoudi Bedra, Benrekaa Nasser, Tiour Faiza, Menari Hamid, Naitbouda Abdelyamine, Manseri Amar, Brik Afaf, Mezghiche Salah, Debbab Moustafa

Opto-Electronics Review

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2023

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Vol. 31, No. 1

art. no. e145096

EN

The structural, morphological and photoluminescent properties of thermally evaporated neodymium oxide (Nd₂O₃) thin films deposited onto nanostructured silicon (Si-ns) are reported. Si-ns embedded in silicon nitride (SiN) thin films are prepared by plasma-enhanced chemical vapour deposition (PECVD). SiN and Nd₂O₃ thin films uniformity and Si-ns formation are confirmed by atomic force microscopy (AFM) and scanning electron microscopy (SEM). The presence of neodymium (Nd), silicon (Si), oxygen (O), and phosphorus (P) is investigated by energy-dispersive spectroscopy (EDS) and secondary ion mass spectrometry (SIMS). Post-annealing SIMS profile indicates an improvement of the homogeneity of activated P distribution in Si bulk. The X-ray diffraction (XRD) combined with Raman spectroscopy and Fourier-transform infrared spectroscopy (FTIR) have been employed to determine amorphous silicon (a-Si), crystalline silicon (c-Si), Nd₂O₃ and SiN phases present in the Nd₂O₃-SiN bilayers with their corresponding chemical bonds. After annealing, a Raman shift toward lower wavenumbers is recorded for the Si peak. XPS data reveal the formation of Nd₂O₃ thin films with Nd-O bonding incorporating trivalent Nd ions (Nd3+). Strong room-temperature photoluminescence is recorded in the visible light range from the Si-ns. Nd-related photoluminescent emission in the near infrared (NIR) range is observed at wavelengths of 1025-1031 nm and 1083 nm, and hence is expected to improve light harvesting of Si-based photovoltaic devices.

3

Effect of ball milling on hexagonal boron nitride (hBN) and development of Al-hBN nanocomposites by powder metallurgy route

Ghosh Arka, Shukla Uddeshya, Sahoo Nityananda, Ganguly Sourav, Shrivastava Pankaj, Kumar Lailesh, Alam Syed Nasimul

Materials Science Poland

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2023

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Vol. 41, No. 1

68--93

EN

This study reports on the exfoliation of bulk hexagonal boron nitride (hBN) by high-energy ball milling and the development of Al-hBN (alumninum-hexagonal boron nitride) nanocomposites by the powder metallurgy (PM) route via the incorporation of the exfoliated hBN in the Al matrix as a nanoreinforcement. The effect of ball milling on the morphology, crystallite size, lattice strain, and thermal stability of hBN powder have also been reported in this paper. Commercially available bulk hBN was ball milled for up to 30 hours in a high-energy planetary ball mill in order to exfoliate the hBN. Although no new phases were formed during milling, which was confirmed by the XRD (x-ray powder diffraction) spectra, ball milling resulted in the attachment of functional groups like hydroxyl (OH) and amino (NH2) groups on the surface of the hBN, which was confirmed by FTIR (Fourier Transform Infrared Spectroscopy) analysis. HRTEM (high resolution transmission electron microscopy) analysis confirmed the synthesis of hBN having few atomic layers of hBN stacked together after 20 hours of milling. After 20 hours of milling, the hBN particle size was reduced from ~1 μm to ~400 nm, while the crystallite size of the 20-hourmilled hBN powder was found to be ~18 nm. Milling resulted in a flake-like structure in the hBN. Although milling involved both exfoliation as well as reagglomeration of the hBN particles, a significant decrease in the diameter of the hBN particles and their thickness was observed after a long period of milling. The average thickness of the 20-hour-milled hBN flakes was found to be ~32.61 nm. HRTEM analysis showed that the hexagonal structure of the milled hBN powder was maintained. Al-based nanocomposites reinforced with 1%, 2%, 3%, and 5% by weight hBN were fabricated by PM route. The Al-hBN powder mixtures were cold-compacted and sintered at 550◦C for 2 hours in argon (Ar) atmosphere. The maximum relative density of ~94.11% was observed in the case of Al-3 wt.% hBN nanocomposite. Al-3 wt.% hBN nanocomposite also showed a significant improvement in hardness and wear resistance compared to the pure Al sample that was developed in a similar fashion. The maximum compressive strength of ~999 MPa was observed in the case of Al-3 wt.% hBN nanocomposite and was approximately twice that of the pure Al sample developed in a similar fashion.

4

Kryminalistyk z Ramanem w ręku. Na tropie śladów zbrodni

Kowalski Mateusz, Walczak Natalia, Szwaczko Katarzyna

Laboratorium - Przegląd Ogólnopolski

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2023

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nr 1

10--17

PL

Niniejszy artykuł przedstawia znaczenie i rolę spektroskopii Ramana w kryminalistyce. Tematy poruszane w artykule obejmują wykorzystanie tej techniki spektroskopowej w wykrywaniu śladów zbrodni na matrycach takich jak: krew, paznokcie, włosy, odciski palców.

EN

This article presents the importance and role of Raman spectroscopy in forensics. The topics covered in the paper include the use of this spectroscopic technique in detecting trace evidence on matrices such as blood, nails, hair, and fingerprints.

5

Raman Spectroscopy Analysis of the Morphology of Gold Nanoparticles Produced by Laser Ablation in Aqueous Proteinogenic Amino Acid for the Detection of Mercury in Water

Carbajal-Morán Hipólito

Journal of Ecological Engineering

|

2023

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Vol. 24, nr 11

169--175

EN

The objective of the research was to analyze by Raman spectroscopy the morphology of gold nanoparticles generated by laser ablation in L-Cysteine of purity ≥ 97% dissolved in ultrapure water for the detection by color change of mercury dissolved in water. Three samples of 10 ml of ultrapure water were prepared with aggregation of 10 ul of L-Cysteine with concentrations of 1, 10 and 20 mM; the generation of the gold nanoparticles was by laser ablation with a wavelength λ = 1064 nm, energy of 60.28 mJ/p located at 30 cm from the convex lens generating ablation at 10 cm on a gold plate of dimensions 10×15 mm with thickness of 1 mm, for 30 min. The gold nanoparticles generated in these aqueous environments were characterized by Raman spectroscopy using a laser with a sensitivity of 785 nm with Raman Shift analysis range 860–3200 cm-1 and controlled power at 499 mW. The nanoparticles presented maximum peak resonance around Raman Shift 1164.96 cm-1 and 1288.06 cm-1. With the AuNPs + L-Cysteine sample with concentration of 10 mM, the author proceeded to the detection of Hg2+ prepared in 20 μl of ultrapure water at concentrations of 0.1, 5 and 10 μM; when adding 100 μl of AuNPs + L-Cysteine two peak absorbance spectra were obtained with different amplitudes observed by UV–Vis spectroscopy, indicating that Hg2+ decreased the repulsion of the negatively charged AuNPs, generating the visible color change for the three concentrations of Hg2+ with 25 minutes of agitation, turning intense purple for 10 μM of Hg2+; enabling the detection of mercury in water.

6

Raman scattering study of meloxicam molecule and DFT calculations of its possible conformers

Skonieczny Robert, Osmałek Tomasz, Froelich Anna, Wiśniewska Maria, Nowicka Ariadna B., Szybowicz Mirosław

Inżynieria Materiałowa

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2023

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Vol. 44, nr 5

16--25

EN

Celem przeprowadzonych badań dla meloksykamu (MLX) było uzyskanie informacji o możliwych izomerach konformacyjnych oraz stabilności termicznej wybranych konformerów MLX. Obliczenia z wykorzystaniem teorii funkcjonału gęstości (DFT) wskazują na cztery możliwe izomery konformacyjne, które zostały porównane z eksperymentalnym widmem ramanowskim leku. Otrzymane wyniki wskazują, że konformer meloksykamu obserwowany w analizowanej próbce jest stabilny w badanym zakresie temperatur.

PL

The aim of the performed studies for meloxicam (MLX) was to obtain information about possible conformational isomerism and the thermal stability of the selected conformers of MLX. Density functional theory (DFT) calculations show four possible conformational isomers which are compared to the experimental Raman spectrum of the drug. The obtained results indicate that the conformer of meloxicam observed in the analyzed sample is stable within the investigated temperature range.

7

Alunogen from the sulfate efflorescence of the Stone Town Nature Reserve in Ciężkowice (the Outer Carpathian Mountains, Poland)

Marszałek Mariola, Gaweł Adam

Geology, Geophysics and Environment

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2023

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Vol. 49, no. 2

139--156

EN

Alunogen (Al2(SO4)3∙17H2O), a rare secondary mineral, has been found in the efflorescence on sandstones from the Stone Town Nature Reserve in Ciężkowice, southeastern Poland. This is probably the first find of this salt on such rocks in Poland. Alunogen forms in various geological environments, but mainly from the oxidation of pyrite and other metal sulfides in ore deposits and Al-rich Earth materials under low-pH conditions. Its crystallization at this particular site depends on a set of necessary physicochemical (pH, concentration), climatic (season, temperature, humidity), site-related (location and protection of efflorescence), and mineralogical (the presence of pyrite) conditions. This paper presents the mineralogical and geochemical characteristics of the alunogen from the Stone Town Nature Reserve (based on SEM-EDS, XRPD, EPMA and Raman spectroscopy methods) as well as of the efflorescence itself (based on XRPD and STA coupled with QMS and FTIR for the analysis of gas products). Crystals of alunogen take the shape of flakes, often with a hexagonal outline, clustered in aggregates forming a cellular network. Its calculated formula is (Al1.96Fe3+ 0.01)∑1.97(SO4)3∙17H2O (based on 12 O and 17 H2O). The unit-cell parameters refined for the triclinic space group P1 are: a = 7.423 (1) Å, b = 26.913 (5) Å, c = 6.056 (1) Å, α = 89.974 (23)°, β = 97.560 (25)°, γ = 91.910 (22)°. The Raman spectra (SO4) bands are: intensive 995 cm−1 (ν1); low-intensive 1069, 1093 and 1127 cm−1 (ν3); low-intensive 419 and 443; medium-intensive 470 cm−1 (ν2); and medium-intensive 616 cm−1 (ν4). Those at 530, 312 and at 338 cm−1 are assigned to water vibrations and those at 135, 156, 180 cm−1 to the lattice modes. Although the efflorescence contained an admixture of other minerals (pickeringite, gypsum and quartz), the predominant alunogen is almost chemically pure and the above parameters are consistent with the values reported in the literature for alunogen from different locations and of various origins.

8

BioLNG - wyzwania pomiarowe w procesie produkcji i układach rozliczeniowych

Kurek Wojciech, Kubaszewski Przemysław

Gaz, Woda i Technika Sanitarna

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2023

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Nr 3

2--5

PL

BioLNG, jeśli chodzi o właściwości, jest niemalże tym samym medium co LNG. Różnice wynikają ze źródła pochodzenia obu. W naszym kraju produkcja LNG, w porównaniu do krajów takich jak Stany Zjednoczone, Katar czy Zjednoczone Emiraty Arabskie jest minimalna. Jednak okazuje się, że w przypadku bioLNG w naszych krajowych zasobach drzemie potencjał, który może być wykorzystany dla produkcji paliwa o ujemnym śladzie węglowym. W artykule przedstawiono dwie kwestie w zakresie produkcji bioLNG: w jaki sposób można przeprowadzić załadunek bioLNG na cysterny kriogeniczne, z jednoczesnym zapewnieniem procedur związanych z prawną kontrolą metrologiczną, a także jak przeprowadzić kontrolę procesu skraplania biometanu, w celu zabezpieczenia instalacji technologicznych, przy wykorzystaniu technologii TDLAS.

EN

BioLNG in terms of properties is almost the same medium as LNG. The differences are due to the source of both. In our country, LNG production is minimal compared to countries such as the United States, Qatar or the United Arab Emirates. However, it turns out that in the case of bioLNG, there is potential in our domestic resources that can be exploited for the production of fuel with a negative carbon footprint. The following article will discuss 2 issues in bioLNG production: how to do loading of bioLNG onto cryogenic tankers with ensuring procedures related to legal metrological control, and how to control the liquefaction process of biomethane to secure process facilities using TDLAS technology.

9

Effect of Microalloying with Ti on the Corrosion Behaviour of Low Carbon Steel in a 3.5 wt.% NaCl Solution Saturated with CO2

Sheikh Ali R.

Archives of Foundry Engineering

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2023

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Vol. 23, iss. 1

5--10

EN

A problem is defined to investigate the effect of titanium traces on the corrosion behaviour of low carbon steel. In theory titanium effects surface properties like abrasion resistance in medium carbon steels and corrosion resistance in low as well as medium carbon steels. The present research as indicated by the topic is aimed to experimentally mark the effect of titanium traces on corrosion resistance in the available low carbon steel specimens. The effect of microalloying with titanium (i.e.0.02wt.%) on the corrosion behavior of low carbon steel in a 3.5 wt.% NaCl solution was studied by electrochemical, SEM, and Raman spectroscopy techniques. The electrochemical results showed that the corrosion of the Ti-bearing steel improved by around 30% compared with the Ti-free steel. The titanium microalloying led to the formation of a more compact corrosion product layer on the metal surface. The SEM analysis showed that the Ti-bearing sample had a smoother surface compared with the Ti-free steel.

10

Spektrometria ramanowska w pomiarach rozliczeniowych LNG

Dzielendziak Janusz, Sutherland Scott

Wiadomości Naftowe i Gazownicze

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2022

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R. 25, Nr 7 (282)

4-8

PL

W ciągu ostatnich kilku lat Europejska Grupa Badawcza Gazu (GERG) podjęła projekt oceny spektroskopii ramanowskiej jako alternatywy dla tradycyjnych ekstrakcyjnych systemów chromatografii gazowej z modułem odparowania do pomiaru składu skroplonego gazu ziemnego (LNG) w ramach pomiarów kontraktowych i fiskalnych. Dzięki zastosowaniu kriogenicznej, światłowodowo sprzężonej sondy optycznej Ramana, pomiary LNG są dokonywane bezpośrednio w fazie ciekłej, co zmniejsza złożoność systemu monitorowania LNG. Niniejszy artykuł zawiera podstawowe informacje na temat spektrometrii ramanowskiej i sprzętu stosowanego do pomiarów LNG, opracowania modelu LNG przy użyciu certyfikowanych materiałów wzorcowych LNG, danych z walidacji obiektowej z instalacji na terminalu Fluxys LNG, końcowych wyników i wniosków z projektu ewaluacyjnego GERG, a także przykładowe wyniki dla instalacji malej skali LNG - kompensacji zapotrzebowania szczytowego, terminalu załadunkowego autocystern oraz bunkrowania statków.

EN

During the past several years, the Europe-an Gas Research Group (GERG) ha; undertaken a project to evaluate Raman spectroscopy as an alternative to traditional gas chromatography/vaporizer systems to measure the composition of liquefied natural gas (LNG) for contractual and fiscal metering. Through the use of a cryogenic fiber optically coupled Raman optical probe, measurements of LNG are made directly in the liquid phase, reducing the complexity of the LNG monitoring system. This paper provides background on the Raman technique and hardware used for LNG measurements, development of the LNG model using certified LNG reference standard samples, field validation data from an installation at the Fluxys terminals LNG discharge line, final results and conclusions of the GERG evaluation project, and exemplary results for field installations at LNG satellite and peak shaving sites and on LNG bunkering vessels.

11

Modification of Optical, Electronic and Microstructural Properties of PET by 150 keV Cs+ Irradiation

Musiatowicz Michał, Turek Marcin, Droździel Andrzej, Pyszniak Krzysztof, Grudziński Wojciech

Advances in Science and Technology. Research Journal

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2022

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Vol. 16, no 5

11–19

EN

Thick (0.125 mm) sheet samples of PET were irradiated with 150 keV Cs+ ion beam with fluences in the range from 10^13 cm^-2 up to 10^16 cm^-2). Raman and UV-VIS spectroscopy measurements shown destruction of numerous bonds within the polymer – this effect intensifies with fluence. Raman spectroscopy shows the presence of amorphous graphitelike structures as the broad G band appears in the collected spectrum. The analysis of absorbance spectra also confirms formation of numerous carbon clusters leading to a formation of vast conducting structures in the modified layer of the polymer. One can observe the decrease of optical bandgap from 3.85 eV (typical for pristine PET) to 1.05 eV for the sample implanted with the highest fluence, the effect is weaker than for lighter alkali metal ions. The estimated average number of C atom in a clusters reaches in such case values close to 1100. The changes in the polymer structure lead to intense reduction of electrical sheet resistivity of the modified samples by ~ 8 orders of magnitude in the case of severely modified sample. The dependence of resistivity on temperature has also been measured. The plots of ln(σ) vs 1/T show that band conductivity or nearest neighbor hopping between conducting structures prevail in the considered case

12

A multi-analytical approach for the analysis of cation distribution in a aluminoceladonite structure

Kądziołka-Gaweł Mariola, Dulski Mateusz, Czaja Maria, Krzykawski Tomasz, Szubka Magdalena

Acta Geologica Polonica

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2022

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Vol. 72, no. 3

353--368

EN

In this paper cation arrangement in two samples of aluminoceladonite, emerald green and dark-green were studied by Mössbauer, Raman and X-ray photoelectron spectroscopies. The X-ray photoelectron spectroscopy (XPS) spectra obtained in the region of the Si2p, Al2p, Fe2p, K2p, and O1s core levels provided information, for the first time highlighting a route to identify the position of Si, Al, K, and Fe cations in a structure of layered silicates. The XPS analysis showed the presence of Al in tetrahedral and octahedral coordination while the K2p line indicated the possibility of K+ substitution by other cations in interlayer sites. Mössbauer spectroscopy provided information about crystal chemistry with respect to the local electronic and geometric environment around the Fe atom and to distortions of the polyhedra. It turned out that iron was located mostly in the cis-octahedra position wherein about 75% of iron appeared in the form of Fe3+. The most preferred cation combinations around Fe corresponded to 3Fe3+ ions and MgFe2+Fe3+/2MgFe3+. Raman spectroscopy illustrated aluminium substitution in silicon and iron positions wherein the concentration of the aluminium determined the degree of structural distortion within the layered system. These isomorphic substitutions implied a typical band arrangement in the hydroxyl region, which has not been observed in celadonites so far.

13

Assessment of the properties of HAp micropowders after ion exchange process in silver nitrate solution

Głuszek Marta, Świrska Zuzanna, Kaczorowski Witold, Januszewicz Bartłomiej, Wrotniak Maciej

Engineering of Biomaterials

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2021

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Vol. 24, no. 161

15--20

EN

Bioceramic materials, such as hydroxyapatite (HAp), are characterized by high biocompatibility in the presence of tissues and body fluids without causing toxic or allergic reactions. Hydroxyapatite, due to its similarity to structures found in bones, is used both in the form of powders, e.g. as additives to bone cements, and implants coatings. However, this material is not characterized by antimicrobial properties, therefore attempts are made to improve its properties by introducing additional elements into the hydroxyapatite structure. Thanks to HAp’s high ion-exchange ability, silver can be introduced into its structure. The calcium ions present in the HAp structure can be easily replaced by silver ions to create a material endowed with high biocompatibility and antibacterial properties. The presented study is based on the analysis of the morphology of the modified powders via scanning electron microscopy (SEM), their chemical composition via X-ray energy dispersive spectroscopy (EDS) and chemical structure via X-ray diffraction (XRD) and Raman spectroscopy. The powders obtained through the ion exchange were mixtures of silver phosphates Ag3PO4 and HAp. The highest silver content was found in the sample modified with a 1M concentration of AgNO3 in the aqueous solution. It was also determined that the annealing of the obtained powders under vacuum at 800°C resulted in the formation of metallic silver and a change in the structure of HAp to β-TCP.

14

Metodyka oznaczania węglowodorów ciężkich C5+ z wykorzystaniem spektroskopii Ramana

Zając Michał A.

Wiadomości Naftowe i Gazownicze

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2020

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R. 23, Nr 1 (255)

17--20

PL

Zagadnienie badania składu płynów eksploatowanych w branży naftowej i gazowniczej jest niezwykle istotne ze względów ekonomicznych oraz bezpieczeństwa. Dotychczasowe metody nie dają satysfakcjonujących rezultatów, dlatego ważne jest poszukiwanie nowych rozwiązań. Jednym z nich jest spektroskopia Ramana. Może zostać ona wykorzystana do pomiarów ilościowych i jakościowych umożliwiając pomiary składu płynu in situ. W pracy zaprezentowano możliwość wykorzystania tej metody w pomiarach węglowodorów C5+ w różnych warunkach termodynamicznych i stanach skupienia. Do pomiarów referencyjnych wykorzystano następujące substancje: 2-metylobutan, n-pentan, n-heksan, heptan oraz oktan. Dane zbierano dla czystych substancji, ich mieszanin o znanym składzie oraz dla próbek kondensatu oraz gazoliny z kopalni gazu. Analiza sygnałów węglowodorów z zakresu 200 cm-1 - 500 cm-1 wykazała, że istnieją istotne i łatwe do wychwycenia różnice w położeniu pików charakterystycznych dla poszczególnych substancji. Ponadto, wykonane badania wskazują, że jest również możliwa analiza ilościowa z wykorzystaniem spektroskopii Ramana. Większość uzyskanych korelacji miała współczynnik Pearsona powyżej 0.9.

EN

The issue of testing the composition of fluids used in the oil and gas industry is extremely important for economic and safety reasons. Existing methods do not give satisfactory results, so it is important to look for new solutions. Raman spectroscopy is one of them. It can be used for quantitative and qualitative measurements enabling measurements of fluid composition in situ. The paper presents the possibility of using this method in C5+ hydrocarbon measurements under various thermodynamic conditions and aggregate states. The following substances were used for reference measurements: 2-methylbutane, n-pentane, n-hexane, heptane, and octane. Data was collected for pure substances, their mixtures of known composition, and for condensate and gasoline samples from a gas mine. Analysis of hydrocarbon signals in the range of 200 cm-1 - 500 cm-1 showed that there are significant and easily detectable differences in the location of the peaks characteristic of individual substances. In addition, the studies performed indicate that quantitative analysis using Raman spectroscopy is also possible. Most of the correlations obtained had a Pearson coefficient above 0.9.

15

Spektroskopia Ramana w zakresie niskich częstotliwości w badaniach materiałów wybuchowych

Liszewska Malwina, Bartosewicz Bartosz, Budner Bogusław, Szala Mateusz, Miczuga Marcin, Kopczyński Krzysztof, Jankiewicz Bartłomiej J.

Przemysł Chemiczny

|

2020

|

T. 99, nr 10

1469--1476

PL

Spektroskopia Ramana stała się w ostatnich latach jedną z ważniejszych technik analitycznych znajdujących zastosowanie w różnych sektorach gospodarki. Wynika to z braku konieczności preparowania próbek do badań, krótkiego czasu pomiaru oraz łatwej identyfikacji badanych substancji na podstawie charakterystycznych widm ramanowskich. W rejestrowanym widmie nieelastycznie rozproszonego światła można wyróżnić zakres 200–4000 cm-1, który odzwierciedla strukturę chemiczną cząsteczki (widmo oscylacyjno-rotacyjne), tzw. odcisk palca, oraz zakres 5–200 cm-1, zwany zakresem niskich częstotliwości, który dostarcza informacji o drganiach sieci krystalicznej w ciele stałym (widmo fononowe). Przedstawiono podstawowe informacje dotyczące spektroskopii Ramana w zakresie niskich częstotliwości, jej możliwości pomiarowych i aplikacyjnych oraz dokonano przeglądu literatury na temat zastosowania tej techniki w badaniach materiałów wybuchowych.

EN

Fundamentals and review with 68 refs.

16

Raman spectroscopy characterization of some Cu, Fe and Zn sulfides and their relevant surface chemical species for flotation

Vázquez-Sánchez Emmanuel E., Robledo-Cabrera Aurora, Tong Xiong, López-Valdivieso Alejandro

Physicochemical Problems of Mineral Processing

|

2020

|

Vol. 56, iss. 3

483--492

EN

Raman spectroscopy as a high-resolution characterization technique was used to analyze various pure metal sulfides immersed in water, namely pyrite (FeS2), chalcopyrite (CuFeS2), sphalerite (ZnS), marmatite (Zn1-XFeXS) and galena (PbS). The Raman characterization was undertaken in situ with the minerals immersed in water. Characteristic Raman spectrum that shows the vibrational modes of the atomic bonds in the mineral crystal structure is reported. This spectroscopic technique revealed that marmatite particles are composed of micro-size, perhaps nano-size, zones with different Fe and Zn content. With the intensity of the Fe-S and Zn-S Raman signals, the iron content of the zones was quantified. The copper ion up-take by marmatite particles was studied through this technique. It was found that the up-take of copper ions on the marmatite zones depended on their Fe content. Copper ion up-take occurred more preferentially on the zones of low Fe content than on those of high Fe content. The adsorption of the collector propyl xanthate on pyrite and chalcopyrite was also assessed by Raman spectroscopy. The Raman spectrum revealed that dixanthogen formed on the surface of these sulfides.

17

Photoluminescence and Raman spectroscopies as an optical approach of stress determining in MOVPE grown quantum cascade laser structures

Łozińska Adriana, Badura Mikołaj, Jadczak Joanna, Bielak Katarzyna, Ściana Beata

Optica Applicata

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2020

|

Vol. 50, nr 2

289--299

EN

In the presented work, an optical approach of stress determining in metalorganic vapor phase epitaxy (MOVPE) grown quantum cascade laser (QCL) structures was reported. In the case of such sophisticated structures containing hundreds of thin layers, it is important to minimize the stress generated in the QCL core. Techniques enabling determination of stress in such thin layers as those described in the article are photoluminescence and Raman spectroscopies. Based on Raman shift or changes in photoluminescence signal, it is possible to analyze stress occurring in the structure.

18

Evaluation of structural, optical and physical properties of polyurethane composites doped with metal alkoxides

Nadafan Marzieh, Anvari Javid Zamir

Materials Science Poland

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2020

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Vol. 38, No. 3

416--423

EN

In this research, polyurethane (PU)/tetraethyl orthosilicate (TEOS) composite was prepared via one-step polymerization method using different concentrations of TEOS in PU. The structural, optical and physical properties of PU composite were characterized by SEM imaging, FT-IR spectroscopy, water uptake, Raman spectroscopy and optical microscopy imaging of synthesized samples. The SEM results showed that by adding TEOS to the PU, the cell and window size of synthesized samples decreased. This result was also observed in the optical micrographs. The bonding characteristics of PU/TEOS composites were analyzed using Raman and FT-IR spectra. According to the FT-IR spectra, the degree of phase separation (DPS) and hydrogen bonding index, R, in 800 µl TEOS/PU had the highest R and DPS factors. By adding different concentrations of TEOS to PU, the apparent density decreased but the real density increased. The total, open and closed porosity of the synthesized samples were calculated. At low loading of TEOS in PU, the open porosity of the samples increased. The PU/TEOS composites may be promising candidates for absorbing sound.

19

A study of nickel and cobalt silicides formed in the Ni/Co/Si(1 0 0) system by thermal annealing

Sedrati C., Bouabellou A., Kabir A., Haddad R., Boudissa M., Taabouche A., Fiad H., Hammoudi A.

Materials Science Poland

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2020

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Vol. 38, No. 3

394--399

EN

In this work, the Ni/Co/Si system was annealed at temperatures ranging from 300 °C to 800 °C. The samples were characterized by means of X-ray diffraction (XRD), Raman spectroscopy, Rutherford backscattering spectroscopy (RBS), atomic force microscopy (AFM) and sheet resistance measurement. The XRD and Raman spectroscopy results showed that the formation of nickel and cobalt silicides (CoSi, Co2Si, Ni2Si, NiSi, NiSi2, CoSi2) is an annealing temperature dependent diffusion process. The diffusion phenomenon was evidenced by RBS. The low values of the sheet resistance which were correlated with the films surface roughness were attributed to the formation of both CoSi and NiSi phases.

20

FTIR and Raman spectroscopic study of a complex perovskite: Ca0.91-xCe0.09Rb0.04Csx [(Zr0.50Ti0.45)Al0.05]O3, x=0.2 to 0.4, dedicated for radioactive waste confinement

Hasnat K., Kamel N., Moudir D., Mouheb Y., Kamariz S., Arabi A.

Advances in Materials Science

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2020

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Vol. 20, nr 2(64)

81--94

EN

Perovskite is able to sequester simultaneously, in its structure, both actinides and alkaline-earth elements. This study is an attempt to synthesize a complex perovskite Ca0.91-xCe0.09Rb0.04Csx [(Zr0.50Ti0.45)Al0.05]O3 (0.2≤x≤0.4), doped in the same time, with Ce, Cs and Rb. The synthesis is conducted by sintering at 1150°C during 16h. XRX analysis confirms the perovskite formation. SEM observations show a less porous microstructure. FTIR analysis reveals TiO6, Ti-O-Ti, Ti-O and Zr-O vibrations. Raman spectroscopy indicates many orthorhombic perovskite active modes, as: Ti-O6 and Ti-O3 torsions, ZrO7, CaO8 vibrations, the totally symmetric oxygen, and the O-octahedron cage rotation.