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1

Diamonds in ureilites

Jakubowski T., Karczemska A., Kozanecki M.

Meteorites

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2011

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Vol. 0, No. 0

3-8

EN

The presence of diamonds in meteorites was confirmed for the first time in the Novo-Ureiureilite in 1888. Ureilites are a rare class of achondrites, often referred to as primitive achondrites. They are composed of olivine and pyroxene (pygeonite), as well as graphite inclusions often coexisting with diamonds. The following three main hypotheses of diamond origin in ureilites have been proposed: the HPHT process, graphite-to-diamond conversion under shock compression due to impact on the parent body (the most popular theory, as of the time of publication), and the CVD process in the solar nebula. The samples of all types of ureilites, from less shocked up to highly shocked, were examined using Raman Spectroscopy and Scanning Electron Microscopy. The results show the presence of diamonds in all of our samples. Of particular significance is the comparison of Raman spectra of diamonds and graphite phases of different ureilites.

2

Wysokotemperaturowe niskotarciowe powłoki na bazie MoO3 i Ag osadzane metodą magnetronową

Makówka M., Pawlak W., Wendler B., Sielski J., Kozanecki M.

Inżynieria Materiałowa

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2011

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Vol. 32, nr 4

553-557

PL

Powłoki na bazie tlenku molibdenu MoO3 oraz srebra osadzono metodą niereaktywnego rozpylania magnetronowego tarcz z MoO3 oraz czystego Ag na ulepszanej cieplnie stali szybkotnącej Vanadis 23, podłożu z tlenku aluminium Al2O3 oraz czystym krzemie. Powłoki poddano wygrzewaniu w zakresie temperatury 150÷550°C i zbadano wpływ wygrzewania na zachodzące zmiany strukturalne w powłokach i ich właściwości. Zbadano ich skład chemiczny metodą EDS, skład fazowy metodą dyfrakcji rentgenowskiej i spektroskopii przesunięć Ramana oraz właściwości tribologiczne za pomocą testu kulka/tarcza. Określona została także jakość adhezji do podłoży stalowych na podstawie testu Daimlera-Benza. Powłoki wykazują bardzo dobre właściwości tribologiczne (współczynnik tarcia suchego o wartości ok. 0,12 i dobra odporność na zużycie na skutek tarcia) w temperaturze powyżej 300°C i z powodzeniem mogą być stosowane jako niskotarciowe powłoki na elementy par ciernych pracujących w podwyższonej temperaturze.

EN

Thin films based on molybdenum oxide and silver were deposited using nonreactive magnetron sputtering of MoO3 and pure silver targets onto Vanadis 23 HS steel, alumina Al2O3 and pure silicon wafers. Deposited coatings were annealed in a range of temperatures from 150°C to 550°C. Influence of annealing temperature on coatings' structure and their structural and tribological properties was studied. Chemical composition using EDS, phase composition using XRD and Raman Shifts Spectrometry as well as tribological properties by means of 'pin-on-disc' test were investigated. Adhesion quality of the coatings to the steel substrates was also studied by Daimler-Benz test. Coatings have very good tribological properties like low coefficient of friction (0.12) and high resistance to wear in temperatures above 300°C and can be applied as low friction coatings for friction couples working in high temperatures.

3

Monitoring ramanowski wzrostu cienkich warstw węglowych : studium

Gnyba M., Kozanecki M., Wroczyński P., Bogdanowicz R.

Elektronika : konstrukcje, technologie, zastosowania

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2010

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Vol. 51, nr 9

113-116

PL

Przedstawiono zagadnienie monitorowania in-situ próżniowego procesu wzrostu cienkich warstw węglowych, w szczególności diamentowych i diamentopodobnych DLC. Zastosowanie pomiarów ramanowskich umożliwia zbadanie struktury warstwy na poziomie molekularnym (zawartości faz węglowych: sp² i sp³, a także defektów wodorowych). Użycie spektroskopii ramanowskiej in-situ podczas procesu syntezy pozwala monitorować poprawność przebiegu procesu i opracować wytyczne do jego optymalizacji. W artykule przedstawiono konfiguracje układów optycznych, problemy doboru długości fali lasera oraz rezulaty prac eksperymentalnych

EN

In this paper we present selected problems referred to Raman in-situ monitoring of growth of carbon-based thin layers, especially - of diamond and diamond-like-carbon layers. Aplication of Raman measurements enables investigation of molecular composition of the layer (content of sp² and sp³ hybrydised carbon as well as presence of C-H defects). In-situ Raman monitoring enables also investigation of process progress and provides data useful for its optimisation. Setups of optical systems used in Raman spectroscopy, problems of exciation wavelengths selection and results experimental work are shown.

4

Energy dispersive X-ray analysis and micro-raman studies of poly(3,4-ethylenedioxythiophene) modified by metal hexacyanoferrates

Nowak A. P., Lisowska-Oleksiak A., Kozanecki M., Kotarba S., Zieliński A.

Advances in Materials Science

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2008

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Vol. 8, nr 1(15)

135-141

EN

Hybrid conducting films, obtained by modification of poly(3,4-ethylenedioxytiophene) doped with Fe(CN)6 4-/3- ions by multicyclic polarization in aqueous FeCl3, NiCl2, and CoCl2 electrolytes, were examined by Energy Dispersive X-ray (EDX) and Micro-Raman measurements. EDX analysis allows to propose composition of metal hexacyanoferate (Mehcf) obtained inside polymer matrix as follows: Fe4[Fe(CN)6]3, Co3[Fe(CN)6]2, NiFe[Fe(CN)6] for materials modified in FeC3, CoCl2 and NiCl2 aqueous electrolytes respectively. Micro-Raman measurements show that the signal from CN is hindered for hybrid systems in comparison with inorganic Mehcf. Stoichiometry of inorganic part of the hybrid materials has been established by means of EDX measurements.

5

Simple model for the thermal conductivity estimation on the basis of Raman and ESR spectroscopy measurements

Masierak W., Fabisiak K., Kaczmarski M., Kozanecki M.

Optica Applicata

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2006

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Vol. 36, nr 2-3

225-234

EN

The diamond films were grown at different working gas pressure in the range of 20-80 mbar by using hot filament chemical vapor deposition (HF CVD) technique. It was observed that the film morphology was dependent on deposition pressure and changed from so called "ball-like" via (111) and (100) type to the morphology of mixed character. The diamond film quality was studied by means of Raman and ESR (electron spin resonance) spectroscopy measurements. Within the presented work a simplified model for heat conductivity was proposed which allows to estimate the value of the thermal conductivity on the basis of Raman and ESR measurements. The obtained results are in good agreement with those reported in literature.

6

Non-mononotonical behaviour of reaction diffusion front width. Simulation studies in frame of dynamic lattice liquid (DLL) model

Polanowski P., Kozanecki M., Pakula T.

Materials Science Poland

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2006

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Vol. 24, No. 2/2

453--466

EN

Investigations of anomalous behaviour of the reaction diffusion front for A + B › 2C (inert) and A + B › CC processes are presented. Computer simulation studies were performed using the model of dynamic lattice liquid (DLL) for both two- and three-dimensional cases. Special attention was paid to situations when the mobility of products C and CC significantly differs from the mobilities of reactants. Under such conditions, new kinds of dynamical behaviour were detected. The results obtained indicate that it is necessary to re-formulate the classical description of reaction diffusion front problem. The generalized formalism suggested in the paper should allow a proper description of dynamics of the reaction front over the whole time range including the case when the mobilities of reactants and products are differ

7

Naprężenia dwuosiowe w warstwach diamentowych nanoszonych na podłoża krzemowe

Staryga E., Klimek L., Fabisiak K., Kozanecki M., Jarzyńska D.

Inżynieria Materiałowa

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2006

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Vol. 27, nr 5

1236-1239

PL

W pracy przedstawione są rezultaty badań naprężeń w polikrystalicznych warstwach diamentowych naniesionych przy użyciu metody HFCVD na podłoża krzemowe. Charakterystykę warstw przeprowadzono przy zastosowaniu takich technik jak: spektroskopia Ramana, skaningowa mikroskopia elektronowa i dyfrakcja elektronów wstecznie rozproszonych. Mikrofotografie powierzchni warstw diamentowych wskazują na polikrystaliczną strukturę, składającą się z ziarn diamentu o rozmiarach rzędu 1 um. Badania umożliwiły identyfikację składu fazowego badanego materiału wskazując na znaczny udział fazy diamentowej w ziarnach polikrystalicznej struktury. Analiza rezultatów wskazuje na brak obecności w badanych warstwach diamentowych takich faz krystalicznych jak lonsdaleit i grafit. W przypadku cienkich warstw diamentowych widoczne są obszary podłoża krzemowego nie pokryte warstwą diamentu a prawdopodobnie pokryte amorficzną warstwą węglową lub warstwą węglika krzemu.

EN

In the paper the results of biaxial stress investigations in polycrystalline diamond films deposited on silicon substrates by HF CVD are presented. The diamond films characteristics were carried out using Raman spectroscopy, SEM and EBSD. SEM images of diamond films surface indicate on the polycrystalline structure with diamond grains about 1 um. The researches enabled the identifications of diamond films phase composition indicating on the considerable concentration of diamond phase in the grains of polycrystalline structure. There is no found the crystalline phase as lonsdaleit and graphite in tested diamond films. In the case of very thin films we can shown the places not covered polycrystalline diamond layer, the silicon substrate is covers by amorphous carbon film or SiC film.

8

Wpływ rodzaju prekursora na jakość warstw diamentowych

Fabisiak K., Banaszak A., Kozanecki M., Jarzyńska D., Staryga E.

Prace Naukowe Politechniki Warszawskiej. Elektronika

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2005

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z. 153

177-180

EN

Very high hardness and broad optical window from UV up to IR make the diamond attractive for many applications. In this work the Raman spectroscopy was used to determine the quality of polycristalline diamond films obtained by Hot Filament Chemical Vapor Deposition Method. Lower contain of amorphous carbon phase and lower value of FWHM of the layers obtained from C(2)H(2) comparing to films obtained from CH(3)OH.

9

Spectroscopic Studies of Sol-Gel Derived Thin-Film Structures for Integrated Optics

Gnyba M., Kozanecki M., Wierzba P.

Molecular and Quantum Acoustics

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2005

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Vol. 26

81-89

EN

Optical methods were applied to investigate sol-gel derived, thin-film components for integrated optics. Raman microscopy yielded information about molecular composition of materials, efficiency of reactions and thickness profile of the structures. Spectroscopic reflectometry, optical microscopy, and low-coherent profilometry confirmed dimensions and shape of the structures.

10

Raman investigation of hybrid polymer thin films

Gnyba M., Keranen M., Kozanecki M., Kosmowski B. B.

Materials Science Poland

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2005

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Vol. 23, No. 1

29--39

EN

Raman spectroscopic studies were carried out for hybrid polymer thin films prepared for photonic applications by the sol-gel technology. Our aims were to analyse the ability of the Raman method toestimate the efficiency of the main reactions of the sol-gel process and to provide information about the chemical composition of the films as well as their thickness, profile, and quality. The difficulties in measurement such as low level of Raman signals, difficulties in data analysis caused by the complex structure of the materials, and the influence of interfering signals, are discussed. The application of Raman microscopy for characterising films based on 3-glycidoxypropyl-trimethoxysilane (GPTS), methacryloxypropyltrimethoxysilane (MPTS), and 3-aminopropyl-trimethoxysilane (APTES) is presented. The efficiencies of reactions of inorganic and organic polymerisation were measured and their products have been identified. The influence of the excitation beam wavelength as well as the type of substrate on the Raman spectra was investigated. Moreover, two-dimensional Raman mapping enabled us to record the thickness profiles of the deposited structures and to detect their defects.

11

Wpływ parametrów plazmy MW/RF na właściwości warstw węglowych

Kaczorowski W., Niedzielski P., Klimek L., Kozanecki M., Mitura S.

Elektronika : konstrukcje, technologie, zastosowania

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2005

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Vol. 46, nr 6

23-24

PL

Zaprezentowano analizę wpływu podstawowego parametru procesu wytwarzania warstw węglowych na ich właściwości. Badania przeprowadzono na powłokach uzyskanych z metanowo-argonowej mieszaniny gazów, przy zmiennych wartościach ujemnego potencjału autopolaryzacji, który determinuje właściwości plazmy MW/RF. Uzyskane wyniki z SEM i mikroanalizatora rentgenowskiego świadczą o tym, że wraz ze wzrostem ujemnego potencjału autopolaryzacji wzrasta szybkość trawienia warstw, a jednocześnie widma Ramana sugerują, że najszybciej trawioną fazą powłoki węglowej jest faza grafitowa.

EN

In this paper, the influence of the basic process parameters on the properties of the carbon coatings were analyzed. Carbon films were deposited by changing the negative bias voltage from mixtures of gases methane/argon - CH4/Ar. The correlation between the negative bias voltage, films structure and Raman spectra was studied. The investigations of deposition was shown, that it was possible created the carbon coating with Id/Ig about 1,94.

12

Czy mikroorganizmy mogą modyfikować twarde warstwy węglowe?

Kaczorowska A., Szczęsna-Antczak M., Antczak T., Bielecki S., Mitura S., Niedzielski P., Kaczorowski W., Kozanecki M., Couvrat P.

Inżynieria Biomateriałów

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2004

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R. 7, nr 35-36

12-16

PL

Badano wpływ różnych drobnoustrojów na powierzchnie pokryte warstwami węglowymi. Powłoki diamentopodobne wytworzono na stali medycznej stosując metodę RF PCVD. Do badań zastosowano próbki z warstwami naniesionymi przy różnych parametrach. Próbki te poddano na działanie komórek mikroorganizmów w warunkach hodowli statycznej w podłożu stałym. Powłoki węglowe przed i po wzroście drobnoustrojów analizowano wykorzystując mikroskop optyczny i fluorescencyjny, skaningowy mikroskop elektronowy oraz spektroskop Ramana. Wyniki badań dowiodły, że niektóre z zastosowanych drobnoustrojów silnie oddziałują z twardą warstwą węglową i prawdopodobnie doprowadzają do zmian jej struktury.

EN

An effect of microorganisms of surfaces covered with carbon coatings has been studied. Carbon films on medical stainless steel have been made using RF PCVD method. The samples covered with carbon coatings under different conditions were used. All samples were inoculated with various microorganisms. The carbon layers before and after the growth of the microbes were examined by means of Raman spectroscopy, scanning electron microscopy and optical microscope. It was found that some of the microbes strongly attacked of the surface of carbon films and probably changed their structure.

13

Plasma deposited hydrogenated carbon silicon films : two amorphous structures of the material

Gubiec K., Tyczkowski J., Kozanecki M.

Karbo

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2003

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Nr 4

240-143

EN

Amorphous hydrogenated carbon-silicon (a-SixCy:H) films were produ- \ ced by plasma enhanced chemical vapor deposition (PECVD) in the audio-frequency (a.f.) three-electrode reactor using tetramethylsilane as a source compound. The negative amplitude of a.f. voltage, V, •., measured on a small electrode, on which the films were deposited, was tnę only operational parameter of the deposition process. Investigations of electrical conductivity, UV VIS optical absorption and Raman scattering were carried out for the films deposited at various V^. It was found that these films are composed of amorphous insulator (a-I) and amorphous semiconductor (a-S) fractions with different electronic structures. On the basis of Raman spectroscopy, it was shown that both sp2 C-C and Si Si bonds are created in the a-S fraction in contrast to the a-I fraction in which C-H groups dominate. A shift of the Si-C band position for a-I and a-S is also observed. Probably, it is connected with a transformation from polymer-like to tetra-hedral glasses structure.

PL

Amorficzne wodorowane cienkie warstwy węgiel-krzem (a-SixCY:H) otrzymywano przez plazmowe osadzane chemiczne z fazy lotnej w zakresie częstości akustycznych (cz.a.) w trój elektrodowym reaktorze z tetra-metylosylanu jako związku wyjściowego. Amplituda ujemna napięcia cz.a. V/j mierzona na małej elektrodzie, na której warstwy były osadzane, była jedynym parametrem zmiennym procesu osadzania. Badania przewodnictwa elektrycznego, absorpcja UV-VIS oraz rozpraszanie Ramana były przeprowadzone dla warstw otrzymanych przy różnych wartościach V,v Stwierdzono, że warstwy te złożone są z części amorficznego izolatora (a-I) i amorficznego półprzewodnika (a-S) o różnych strukturach elektronicznej. W oparciu o spektroskopię Ramana wykazano, że oba wiązania sp2 dla C-C oraz Si-Si powstają w strukturze a-S w przeciwieństwie do struktury a-I, w której dominujągrupy C-H. Obserwuje się także przesunięcie pasma od Si-C przy przejściu od a-I do a-S. Przypuszczalnie jest to wynikiem transformacji struktury szkłopodobnej.

14

Cellulose Derivatives : Organic Crystals and Liquid Crystals : Used the Longest, Known the Least

Kryszewski M., Wojciechowski P., Okrasa L., Kozanecki M., Ulański J.

Polish Journal of Chemistry

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2002

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Vol. 76 / nr 2-3

187-200

EN

The basic characteristic of cellulose chemical constitution and its crystalline structure are presented. The LC-phases of cellulose derivatives were investigated by a series of techniques, which made possible to establish the specificity of chiral nematic mesomorphic structure and its transitions in correlation with intermolecular interactions of the side chains. The anisotropic composites, formed by stabilization of mesomorphic phase of LC-cellulose derivatives by photopolymerization of lyotropic solvent (acrylic acid), are characterized by thermooptical analysis, dielectric spectroscopy, dynamic mechanical measurements, WAXS and Raman spectroscopy. These techniques show that the structure of the vinyl polymer within the composite is dependent on the oriented mesophase. The vinyl polymer phase in the glassy state counteracts the relaxation of LC-cellulose derivatives leading to its stabilization and reorientation in the heating and cooling cycles. These properties suggest such composites as materials of interesting from both fundamental and practical points of view.

15

Raman investigation of sol-gel-derived hybrid polymers for optoelectronics

Gnyba M., Keranen M., Kozanecki M., Bogdanowicz R., Kosmowski B. B., Wroczyński P.

Opto-Electronics Review

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2002

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Vol. 10, No. 2

137-143

EN

A Raman spectroscopic study was carried out in order to investigate the synthesis process of organically modified silane (ORMOSIL) hybrid polymers. These materials were prepared for optoelectronic application, using the sol-gel technology. Our aim was to analyse the ability of Raman measurements to estimate the efficiency and correctness of particular stages of the technological process. To synthesise a hybrid for optical planar waveguides, denoted as GSiC, a system of 3-glycidoxypropyl-trimethoxysilane/methacryloxy-propyltrimethoxysilane (GPTS/ MPTS) was used as a precursor. To diagnose the first step – gelation – the Raman spectra of monomers and gel were recorded. Analysis showed that gelation parameters should be improved to in-crease the efficiency of monomers hydrolysis and epoxy ring opening in GPTS. After next two steps – deposition and hardening – Raman microscopy was used for the characterisation of polymer thin films. Information about the film thickness, open-ing of double C=C bonds in MPTS and types of bonds in organic and inorganic part was obtained. Raman spectroscopy proved its considerable potential in technological process diagnostics. A molecular structure of components can be con-trolled at relevant stages of the synthesis. This is necessary in order to design new materials on a molecular level and obtain required properties and good quality of the final product.

16

Diagnostyka ramanowska w procesie wytwarzania polimerów hybrydowych dla optoelektroniki

Gnyba M., Keränen M., Bogdanowicz R., Kozanecki M.

Elektronizacja : podzespoły i zastosowania elektroniki

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2002

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nr 4

5-9