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1

Multiscale water drop contact angles at selected silica surfaces

Zhang Chen, Wang Xuming, Li Lixia, Jin Jiaqi, Polson Randy, Miller Jan D.

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 5

art. no. 152154

EN

In this study, multiscale advancing contact angles for glycerol/water drops at silica surfaces are reported for millidrops, submicron-drops, and nanodrops. Selected silica surfaces were muscovite, silicon, and talc. The contact angles for millidrops (1–2 mm) were determined by the traditional sessile drop technique. For submicron-drops (0.1–1.0 μm), a hollow tip Atomic Force Microscope (AFM) procedure was used. The contact angles for nanodrops (~7 nm) were examined from Molecular Dynamics (MD) simulation. The results were compared to evaluate the effect of drop size on the contact angle. In the case of the hydrophobic talc surface, the 75° advancing contact angle did not vary significantly with drop size. For the hydrophilic muscovite surface, the water drop wet the surface and an advancing contact angle of about 10° was found for the millidrops and submicron-drops. However, for the MD simulated nanodrops, attachment and spreading of the ~7 nm drop created a 2D film of molecular dimensions, the contact angle of which was difficult to define and varied from 0° to 17°. Perhaps of equal interest from the MD simulation results was that the spreading of the glycerol/water nanodrop at the muscovite surface resulted in crystallographic directional transport of water molecules to the extremities of the 2D film. Such separation and segregation left the center of the film with an increased concentration of glycerol. Based on these results, the line tension, which has been found in other investigations to account for contact angle decrease with a decrease in drop size, does not seem to be a significant factor in this study.

2

Diffuse-layer surface potentials of colemanites mined in Turkey

Senol-Arslan Dilek, Drelich Jaroslaw W.

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 5

art. no. 151933

EN

Colemanite crystal specimens were handpicked at Kestelek, Emet (Hisarcik, Espey), Bigadic mines in Turkey for characterization of their composition and surface potential. X-ray diffraction analysis revealed no differences in mineralogical makeup of the crystals, but elemental analysis indicated differences in the type of trace (<0.1 wt%) elements. Zeta potential measurements showed small differences in zeta potential values, with isoelectric points (iep) varying from about pH = 9.6 to pH = 10.2. However, no correlation was found between iep and the type of trace elements. Additionally, atomic force microscopy (AFM) was employed to measure the colloidal interactions between a silicon nitride (Si3N4) cantilever tip and colemanite crystal surfaces in 1 wt% colemanite-saturated aqueous solutions at three different pHs (8.4, 9.4 and 11). The Derjaguin-Landau-Verwey-Overbeek theory (DLVO) was applied to examine the AFM tip interactions with colemanite surfaces in an aqueous solution of colemanite saturated solutions. The results revealed attractive forces at pH = 8.4 and 9.4 and repulsive forces at pH = 11, confirming the location of an isoelectric point for colemanite specimens somewhere between pH = 9.5 and pH = 10.1. Theoretical analysis of the force curves using the DLVO theory allowed for assessment of both surface charge density and surface potential for colemanite specimens used in this study.

3

Cartilage tissue examination using atomic force microscopy

Paluch Jarosław, Markowski Jarosław, Pilch Jan, Smółka Wojciech, Jasik Krzysztof Piotr, Kilian Filip, Likus Wirginia, Bajor Grzegorz, Chrobak Dariusz, Glowka Karsten, Starczewska Oliwia

Engineering of Biomaterials

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2022

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vol. 25, no. 167

17--23

EN

Life sciences, a field closely intertwined with human biology and physiology, employ various research methods, including morphology studies and quantitative analysis through non-destructive techniques. Biological specimens often consist of three-phase structures, characterized by the presence of gas, liquid, and solid components. This becomes crucial when the chosen research methodology requires the removal of water from samples or their transfer to a cryostat. In the current research, mechanical and topographical examination of cartilage was performed. The materials were generously provided by the Department of Anatomy at the Medical University of Silesia, thereby eliminating any concerns regarding their origin or ethical use for scientific purposes. Our research methodology involved the application of atomic force microscopy (AFM), which minimally disrupts the internal equilibrium among the aforementioned phases. Cartilage, recognized as a ‘universal support material’ in animals, proves to be highly amenable to AFM research, enabling the surface scanning of the examined material. The quantitative results obtained facilitate an assessment of the internal structure and differentiation of cartilage based on its anatomical location (e.g., joints or ears). Direct images acquired during the examination offer insights into the internal structure of cartilage tissue, revealing morphological disparities and variations in intercellular spaces. The scans obtained during the measurements have unveiled substantial distinctions, particularly in the intercellular ‘essence’, characterized by granularities with a diameter of approximately 0.5 μm in ear cartilage and structural elements in articular cartilage measuring about 0.05 μm. Thus, AFM can be a valuable cognitive tool for observing biological samples in the biological sciences, particularly in medicine (e.g. clinical science).

4

Surface forces in chemical mechanical planarization and semiconductor wafer cleaning systems

Hupka Lukasz, Nalaskowski Jakub, Miller Jan D., Hupka Jan

Wiadomości Chemiczne

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2021

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[Z] 75, 9-10

1229--1240

EN

Superior uniformity and local planarity of semiconductor wafers in the chemical mechanical planarization (CMP) process as well as efficient post-CMP cleaning is controlled by surface chemistry phenomena. The AFM colloidal probe technique was used to demonstrate surface forces which are of special significance to CMP and post-CMP cleaning. Examples of ways to manipulate those interactions are provided, and the benefits to CMP processes and post-CMP cleaning are discussed.

5

In situ-formed bacterial exopolysaccharide (EPS) as a potential carrier for anchorage-dependent cell cultures

Komorowski Piotr, Kołodziejczyk Agnieszka, Makowski Krzysztof, Kotarba Sylwia, Walkowiak Bogdan

Engineering of Biomaterials

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2021

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Vol. 24, no. 159

18--23

EN

The study involved the use of a bacterial strain isolated from environmental samples which produce the biopolymer in the form of pellets in the submerged culture. This material (bacterial exopolysaccharide) is produced by bacteria of the Komogateibacter xylinus which are prevalent in the environment. The aim of this study was to characterize bacterial exopolysaccharides and commercial dextran-based “microcarriers” in terms of their roughness and cell culture effects, including the morphology and viability of the human hybridoma vascular endothelial cell line EA.hy926. The pellets were characterized using scanning electron microscopy (SEM) and atomic for¬ce microscopy (AFM). The resulting structures were used for cell culture of adherent cells (anchorage¬-dependent cells). At the same time, the cultures with commercial, dextran-based “microcarriers” were carried out for comparative purposes. After com¬pletion of the cell culture (24 hours of culture), the cellulose and commercial “carriers” were analyzed using SEM and AFM. Finally, the obtained cell dens¬ities (fluorescence labelling) and their morphological characteristics (SEM) were compared. The obtained results strongly support the applicability of bacterial exopolysaccharide (EPS) in tissue engineering to build innovative 3D scaffolds for cell culture, the more so that it is technologically possible to produce EPS as spatially complex structure

6

Atomic force microscopy with fractal studies of temperature induced changes in the surface topography of polymeric materials

Rydzkowski Tomasz, Kulesza Sławomir, Bramowicz Mirosław, Michalska-Pożoga Iwona

Polimery

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2020

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T. 65, nr 1

25--32

EN

Changes in the surface topography of polymeric materials can be analyzed to find the correspondence between observed surface features and specific external factors that might also influence physical and functional properties of the investigated material. In this work, atomic force microscopy (AFM) measurements were carried out to investigate the thermal changes in the surface topography as well as in the inner structure of the low density polyethylene (LDPE) samples subjected to 10 recirculations (rLDPE). For better assessment, fractal analysis and AFM results were additionally compared to DSC tests results.

PL

Analiza zmian topografii powierzchni materiałów polimerowych pozwala wyznaczyć zależności między obserwowanymi cechami powierzchni a określonymi czynnikami zewnętrznymi, które mogą wpływać na właściwości fizyczne i funkcjonalne badanego materiału. W niniejszej pracy metodą mikroskopii sił atomowych (AFM) oceniano zmiany termiczne topografii powierzchni, a także wewnętrznej struktury próbek polietylenu małej gęstości (LDPE) poddanych 10-krotnej recyrkulacji (rLDPE). Wyniki AFM i analizy fraktalnej porównywano z wynikami badań metodą różnicowej kalorymetrii skaningowej (DSC).

7

Thin films of copper phthalocyanine deposited by solution processing methods

Gojzewski Hubert, Ghani Fatemeh, Szybowicz Mirosław

Materials Science Poland

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2020

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Vol. 38, No. 1

79--90

EN

In this work, we show and discuss the surface structure picture of copper phthalocyanine (CuPc) thin films deposited from trifluoroacetic acid (TFA) solvent onto silicon substrates at ambient conditions by four solution processing methods, namely drop-casting, dip-coating, spin-casting and spray-coating. The CuPc films were studied by AFM, as the main technique, and complemented by micro-Raman spectroscopy. Essentially, such thin films consist of CuPc molecular nanoribbons of a fixed ~1 nm thickness. CuPc molecules are arranged in an in-plane direction and formed in stacks under a defined tilt angle with respect to the substrate surface (monolayer) or underlying CuPc layer (multilayer). The film morphology takes various forms depending on the solution concentration, number of layers, and the deposition method. For instance, the morphology varies from very wide (~600 nm) but flat (~1 nm) ribbons for films prepared by dip-coating to crystallized rod-like features (multi-layered ribbons) when obtained by spray-coating. The factors studied in this paper should be taken into consideration in designing and controlling the criteria for rigorous CuPc film architecture.

8

Surface micromorphology analysis of Cu/Ni nanocomposite thin films by power spectra density and fractal geometry

Nikpasand Kimia, Elahi Seyed Mohammad, Sari Amir Hossein, Boochani Arash

Materials Science Poland

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2020

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Vol. 38, No. 2

328--333

EN

Copper (Cu) and nickel (Ni) nanoparticles have been grown simultaneously on glass and silicon substrates by RF sputtering method to form three Cu/Ni nanocomposites at different deposition times. The existence of Cu and Ni peaks in the X-ray diffraction (XRD) profiles confirms the crystalline structure of samples with Cu and Ni atomic content which have also been characterized by Rutherford backscattering (RBS) method. Moreover, the structural and morphological properties of the prepared nanocomposites have been compared with respect to their morphologies by means of atomic force microscopy (AFM) analysis. In order to compare the surface roughness over different spatial frequency ranges and evaluate surface quality, power spectral density (PSD) of each sample has been extracted from AFM data and also, the experimental and theoretical results have been compared. The fractal nature of these nanocomposites has been finally discussed.

9

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.

10

Microscopic analysis of the nanostructures impact on endothelial cells

Kołodziejczyk Agnieszka Maria, Kucińska Magdalena, Jakubowska Aleksandra, Siatkowska Małgorzata, Sokołowska Paulina, Kotarba Sylwia, Makowski Krzysztof, Komorowski Piotr, Walkowiak Bogdan

Engineering of Biomaterials

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2020

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Vol. 23, no. 154

2--8

EN

Nowadays nanostructures are more and more often designed as carriers for drug delivery, especially to improve the drug pharmacokinetics and pharmaco-dynamics. Numerous kinds of nanostructures are considered a good prospect for medical applications thanks to their small size, acceptable biocompatibility and toxicity. Due to the fact that nanotechnology is a new field of science, every nano-scale product must be thoroughly examined regarding its toxicity to the human body. This study provides new insights into effects of exposing endothelial cells to the selected nanostructures. Dendrimers of the fourth generation (PAMAMs), multi-walled carbon nanotubes (MWCNTs) and silver nanoparticles (SNPs) were used to evaluate nanostructures influence on endothelial cells in vitro. The nanostructures were evaluated via transmission electron microscopy and dynamic light scattering technique. The cells previously exposed to the nanostructures were observed and analyzed via the atomic force microscopy and scanning electron microscopy to obtain a quantitative evaluation of the cells morphology. The presence of multi-walled carbon nanotubes and silver nanoparticles on the cells surface was confirmed by the scanning electron microscopy. Our results confirm that the surface association and/or uptake of nanostructures by the cells resulting from physicochemical and biological processes, affect the cells morphology. Morphological changes can be induced by the membrane proteins interaction with nanomaterials, which trigger a sequence of intracel-lular biological processes.

11

Characteristics and Properties of Chromium Coatings with Diamond Nanoparticles Deposited Directly on Aluminum Alloys

Petkov V., Valov R., Simeonova S., Kandeva M.

Archives of Foundry Engineering

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2020

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Vol. 20, iss. 4

115--120

EN

The objective of this study was to deposit directly chromium with diamond nanoparticles (ND) on aluminum alloys and investigate the coating surface. The chromium coatings on aluminum alloys were obtained by electrochemical deposition. The coatings were doped with ND. The diamond nanoparticles were obtained by detonation synthesis. Chromium coatings were deposited on aluminum alloys with a silicon content of 7 % and 10 %. The ND concentration in the electrolyte was 25 g/l. The surface analysis was performed by means of Atomic force microscopy. The surface of the coating of chromium with ND on Al10Si is twice more even than that on Al7Si. The microstructure and microhardness were examined with a metallographic microscope and a microhardness tester. The microhardness of the coated samples is 9163 MPa compared to 893 MPa of uncoated aluminum samples. The thickness of the chromium coatings doped with diamond nanoparticles is between 45 – 55 μm. The coatings are dense, continuous and uniform with good adhesion to the substrate material.

12

The impact of the light exposure on the morphological properties of selected photoresists

Sikora Andrzej, Janus Paweł, Sierakowski Andrzej

Optica Applicata

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2019

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Vol. 49, nr 1

177--185

EN

In this paper we present the investigation aimed at the photoresist roughness change determination as a reliable estimator of the exposition rate in the processing verification in semiconductor industry. By employing atomic force microscopy as the 3D high resolution surface imaging tool, we tested twelve popular photoresists in terms of the morphological properties changes, while the following radiation doses were applied. Basing on high precision, and repetitive sample positioning, it was possible to perform the tests with high degree of confidence and observe the roughness change dynamics. Various profiles of roughness changes were observed, showing the need for individual study of each material. Moreover, it was possible to select the photoresists which due to poor homogeneity and small roughness changes are not suitable to such a verification. According to our knowledge, no such study was performed so far.

13

Zastosowanie mikroskopu sił atomowych w badaniach materiałów stomatologicznych

Ziębowicz Bogusław, Ziębowicz Anna

LAB Laboratoria, Aparatura, Badania

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2019

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R. 24, nr 4

16--20

14

Metody badawcze cienkich warstw wytworzonych metodą osadzania warstw atomowych

Boryło Paulina, Szindler Marek, Szindler Magdalena, Lukaszkowicz Krzysztof

LAB Laboratoria, Aparatura, Badania

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2019

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R. 24, nr 5

16--18

15

Aging of carbon nanotube-filled fluoroelastomer in oil-based drilling fluid

Heidarian J.

Polimery

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2018

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T. 63, nr 3

191--212

EN

Carbon nanotube (CNT)-, carbon black (CB)-filled fluoroelastomer (FE) and unfilled FE compounds were prepared (CNT/FE, CB/FE and FE). The oil-based drilling mud (OBD) aging resistance of these elastomers were assessed by tests of atomic force microscopy (AFM), optical microscopy and X-ray diffractometry (XRD). Weight gain, swelling and hardness were also determined. The whole conclusion is that CNT/FE can be used as O-rings in OBD drilling while FE and CB/FE can not.

PL

Metodami mikroskopii optycznej, mikroskopii sił atomowych (AFM) i dyfraktometrii rentgenowskiej (XRD) badano odporność starzeniową kompozytów na bazie fluoroelastomeru (FE) napełnianego nanorurkami węglowymi (CNT) lub sadzą węglową (CB), poddanych działaniu płuczki wiertniczej na bazie oleju (OBD). Oznaczano też przyrost masy, stopień spęcznienia i twardość próbek poddanych starzeniu w środowisku płynu wiertniczego. Stwierdzono, że fluoroelastomer napełniony nanorurkami węglowymi jest odporny na działanie płynu wiertniczego i można go stosować w materiale uszczelek w urządzeniach wiertniczych wykorzystujących płuczki na bazie oleju.

16

Influence of alloying elements on adhesion of corrosion relevant microorganisms

Telegdi J.

Ochrona przed Korozją

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2018

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nr 6

150--154

EN

Corrosion relevant microorganisms enhance the rate of corrosion by their presence, by the excreted metabolites and by the exopolymeric substances. Biofilm formed by microbes influences the surface reactions at the metal/biofilm interface. Surface properties (homogeneity of oxide layer, surplus of alloying elements, pH, interference between the exopolymers and the metal ions as well as between the aggressive metabolites and the metal surface) have significant impact on the adhesion of microorganisms and on the biofilm formation. The corrosion relevant microorganisms are mostly dangerous in sessile form, embedded into biofilms, much less in planktonic form. This paper shortly discusses the microbially influenced corrosion (MIC) and its mechanisms and mainly focuses on the influence of the alloying metals on the microbial adhesion, biofilm formation and, as a consequence, on the MIC. Biofilms discussed here are formed either by isolated pure culture (Desulfovibrio desulfuricans) or by mixed population of cooling water on iron and on iron alloys with alloying elements:chromium, nickel, molybdenum and ruthenium. The surface with and without biofilms were visualized by light-, fluorescence- and atomic force microscopes. Microbiological techniques helped in enumeration of microorganisms. Correlation was found between the chemical nature/ concentration of the alloying elements and the number of microorganisms built in the biofilm.

PL

Mikroorganizmy związane z korozją przyspieszają procesy korozyjne poprzez swoją obecność, wydzielane metabolity oraz substancje egzopolimeryczne. Biofilm utworzony przez mikroorganizmy wpływa na reakcje powierzchniowe na granicy metalu i biofilmu. Właściwości powierzchni (homogeniczność warstwy tlenowej, nadbudowanie elementów stopowych, pH, interferencja między egzopolimerami a jonami metalu oraz między agresywnymi metabolitami a powierzchnią metalową) mają znaczący wpływ na adhezję mikrooranizmów oraz na powstawanie biofilmu. Mikroorganizmy związane z korozją są w dużej mierze niebezpieczne w formie osiadłej, występujące w biofilmach, a mniej niebezpieczne w formie planktonowej. Niniejsza praca krótko opisuje korozję biologiczną oraz jej mechanizmy i skupia się głównie na wpływie metali stopowych na adhezję mikroorganizmów, powstawanie biofilmu i, w konsekwencji, na korozję biologiczną. Omawiane biofilmy były tworzone z wykorzystaniem wyodrębnionej czystej kultury (Desulfovibrio desulfuricans), lub też z wykorzystaniem zespołu mikroorganizmów wody chłodzącej na powierzchni żelaza i jego stopach z pierwiastkami stopowymi: chromem, niklem, molibdenem i rutenem. Powierzchnie z biofilmami i bez nich zostały ukazane w mikroskopach: optycznym, flurescencyjnym i atomowym. Techniki mikrobiologiczne pomogły w wyliczeniu mikroorganizmów. Znaleziono korelację pomiędzy chemiczną naturą/koncentracją elementów stopowych a ilością mikroorganizmów zbudowanych w biofilmie.

17

Use of scanning area related multiple degradation profiles for AFM assessment of polystyrene/PC61BM nanocomposite surface deterioration

Sikora A., Moczała M., Boharewicz B.

Materials Science Poland

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2018

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Vol. 36, No. 3

397--402

EN

In this paper, we present a novel approach developed in order to increase the reliability and accuracy of AFM investigation of morphological changes in a nanocomposite due to exposure to the media causing its degradation. By precise sample positioning and repetitive determination of the roughness changes at specific spots, we were able to create space-related degradation profiles. As the multi-step experiment based on exposure/scanning cycle was performed, we were able to observe a unique response of investigated samples revealing spatial inhomogeneity of the material. In order to present the measurement methodology, we used polystyrene samples containing various quantities of PC61BM nanofiller (0 %, 5 %, 10 % and 20 % of mass proportion), which was exposed to 370 nm UV radiation. Obtained data can be recognized as specific fingerprints of investigated materials. The solution based on creation and analysis of degradation profiles can be particularly useful for diagnostics of nanomaterials and nanocomposites to test their resistance to various conditions.

18

Morphological, optical and electrochromic properties of dry-lithiated nanostructured WO3 thin films

Madhuri K. V., Babu M. B.

Materials Science Poland

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2018

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Vol. 36, No. 2

341--347

EN

Tungsten trioxide (WO3) thin films were prepared by thermal evaporation technique on thoroughly cleaned glass substrates at high pressure of 133.322 mPa in presence of argon. The substrate temperature was maintained from 6 °C to 8 °C with the help of a cold jar. The deposited films were annealed at 400 °C in air for about 2 hours. The films were characterized in terms of their composition by X-ray photoelectron spectroscopy. Subsequently, the laboratory developed dry lithiation method was used to intercalate lithium atoms into as-deposited films in various proportions. With the amount of lithium content inserted into the film, the films showed coloration in visible and near infrared regions. The morphology, coloration efficiency and optical constants of annealed and lithiated films were calculated.

19

Investigations of reconstruction of passivation layer on stainless steel surface using AFM-based techniques

Błaszczyk M., Durko M., Iwanicka Z., Lochyński P., Sikora A.

Materials Science Poland

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2018

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Vol. 36, No. 3

381--386

EN

Continuous development of stainless steel technology forced by the increase in the growing demands on the operating parameters of various stainless steel alloys, is the motivation for implementation of research for understanding the complexity of electrochemical processes ongoing on the surface of a material during various technological processes and during exploitation of the finished components. In this paper, the use of atomic force microscopy (AFM) is presented as a tool for observation of reconstruction process of passivation layers on the surface of previously electropolished stainless steel. For this purpose, a technique called nanoscratching was used, in which scratches are made on the surface of a material by means of diamond scanning probe, which violates the continuity of the passivation layer. Then, the dynamics of the process of reconstruction of that layer was assessed using continuous imaging of the scratched area in AFM semicontact mode. Studies of this type can be used to evaluate the impact of various factors on the spontaneous reconstruction of the passivation layer as well as possible susceptibility of the material on the course of corrosion processes initiated as a result of mechanical defects arising during operation of the material. By using the AFM, it was possible to observe changes in the depth of scratches with a subnanometer resolution. Obtained results proved that the presented AFM application allowed observation of the dynamics of passivation layer reconstruction process in a quantitative fashion, therefore it seems to be a very useful tool in the investigation of the impact of various conditions on this phenomenon. The results showed that changes in surface modification were occurring in a continuous manner. Changing dynamics of said process was presented. It should be underlined that no such experiments have been reported so far.

20

Application of argon plasma sheet in the etching process of calcium carbonate crystals for AFM tests

Moczała M., Karpińska M., Poznar M., Dobryszycki P., Sikora A.

Materials Science Poland

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2018

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Vol. 36, No. 1

75--79

EN

This paper presents utilization of argon plasma for gradual etching of calcium carbonate crystals. The plasma treatment has been chosen as it appears to be the technique that enables removal of following material layers, thus, the access to the inside of crystals is possible. Examples of investigations of the morphology and mechanical properties of surfaces of calcium carbonate crystals are presented. The impact of plasma treatment has been verified in terms of roughness and volume changes investigated using atomic force microscopy technique in a multi-step experiment. Therefore, we were able to observe the crystal degradation process, revealing the spatial inhomogeneity of the calcium carbonate crystals resulting from their core-shell structure.