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1

Nanocomposites of nanocarbon functionalized carbon fibers — manufacturing to methodological applications

Kausar Ayesha, Ahmad Ishaq

Advances in Materials Science

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2024

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Vol. 24, nr 1(79)

46--71

EN

Carbon fibers have been technically applied in high performance materials and industrial scale applications. Importantly, carbon fiber reinforced composite materials have found applications in aerospace industries. These properties of carbon fiber reinforced composites depend upon the carbon fiber features such as length, orientation, surface properties, adhesion with matrices, etc. To improve the surface properties of carbon fibers and adhesion and interactions with polymers, fiber modification has been suggested as an efficient approach. Carbon nanoparticle or nanocarbon functionalized carbon fibers have been manufactured using various facile physical and chemical approaches such as electrospraying, electrophoretic deposition, chemical vapor deposition, etc. Consequently, the modified carbon fibers have nanocarbon nanoparticles such as graphene, carbon nanotube, nanodiamond, fullerene, and other nanocarbons deposited on the fiber surface. These nanocarbon nanoparticles have fine capability to improve interfacial linking of carbon fibers with the polymer matrices. The chemical vapor deposition has been adopted for uniform deposition of nanocarbon on carbon fibers and chemical methods involving physical or chemical modification have also been frequently used. The resulting advanced epoxy/carbon fiber/nanocarbon composites revealed improved tensile and physical profiles. This review basically aims manufacturing and technical aspects of polymer/fiber/nanofiller nanocomposites toward the development of high performance structures. The resulting morphology, strength, modulus, toughness, thermal stability, and other physical features of the nanocarbon functionalized carbon fibers have been enhanced. In addition, the fabricated polymer/fiber/nanofiller nanocomposites have fine interfacial adhesion, matrix-nanofiller-filler compatibility, and other characteristics. The application areas of these nanomaterials have been found wide ranging including the strengthened engineering structures, supercapacitors, shape memory materials, and several others.

2

The effect of stream power in the instability and morphological changes of Haji Arab River, Buin Zahra (Qazvin Province, Iran)

Hosseinzadeh Mohammad Mahdi, Khaleghi Somaiyeh, Safari Fateme, Zarandini Fateme Rezaian

Studia Quaternaria

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2023

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Vol. 40, Nr 1

25--35

EN

The stream power is one of the important river variables which is used in morphological analysis. Therefore, the stream power determines both erosion and deposition. This research examines the stream power, instability and morphometric changes of the channel using the annual geomorphic energy (AGE) in Haji Arab River in Buin Zahra (Qazvin Province). The AGE is calculated by integrating the relationship between the excess specific stream power and discharge using a flow duration curve. The AGE values for each reach should be either positive or negative. Therefore, according to the differentials in AGE values, depositional and erosional reach are determined. In this paper, the results of the AGE method were compared with the rapid geomorphic assessments (RGA), including the channel stability indicators (CSI) model and OSEPI index. Also, the RHS method based on the field works was used to identify depositional and erosional geomorphic landforms. Comparing the results of the AGE with rapid RGA indices, shows that results of the OSEPI are more consistent with the erosional and depositional status of the reaches, based on the AGE. Spatial variations in lithology and structure, when combined with the course of the Haji Arab River indicate that channel morphometry locally reflects geological factors that have caused slope differences in different reaches. The calculated AGE values at different cross-sections have significant variability, reflecting characteristic local variation in bed slope, cross-section geometry and bed-sediment composition.

3

Perspective applications of plasma-deposited thin film nanocatalysts on structured supports: from CO2 capture to wastewater treatment

Kierzkowska-Pawlak Hanna, Bilińska Lucyna, Tyczkowski Jacek

Ecological Chemistry and Engineering. S

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2023

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Vol. 30, nr 4

489--504

EN

The urgent need for sustainable solutions to environmental challenges has led to significant research efforts towards innovative processes and technologies capable of addressing global issues such as carbon dioxide (CO2) capture and valorisation as well as efficient water-reuse cycles. The majority of processes involved in CO2 conversion require highly active catalysts for practical implementation. Concurrently, wastewater treatment technologies, critical for achieving sustainable water reuse, often rely on complex multi-stage systems that incorporate advanced oxidation processes (AOPs). Optimising reaction conditions and exploring unconventional approaches to catalytic system design are crucial for enhancing the efficiency of these processes. Among the emerging solutions, the application of thin-film catalysts deposited by cold plasma onto various structured supports has shown promising potential for improving process performance to meet environmental goals. This paper discusses recent advancements in the development of thin-film nanocatalysts based on cost-effective transition metals. It highlights their application in gas-phase reactions, such as CO2 hydrogenation to value-added products, as well as innovative uses in multiphase gas-liquid systems, including CO2 capture in aqueous solvents and the ozonation of wastewater.

4

Electrolytic deposition of zinc-nickel alloy coatings with organic addition

Domańska Aleksandra J., Skitał Piotr M.

Ochrona przed Korozją

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2021

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nr 11

358--362

EN

The obtaining and investigation of the properties of zinc-nickel coatings deposited using the chronopotentiometric technique were conducted. The deposition was carried out at constant temperature, using different values of current density and in the presence and absence of an organic compound. Sodium benzenesulphonate (SBS) was used as a bath additive. The structure, composition and properties of the coatings were studied using SEM-EDS, optical-digital microscopy, while the corrosion resistance was investigated using corrosion potential as a function of time and the potentiodynamic method.

PL

Opracowano i zbadano właściwości powłok cynkowo-niklowych osadzanych techniką chronopotencjometryczną. Osadzanie prowadzono w stałej temperaturze, stosując różne wartości gęstości prądu oraz w obecności i nieobecności związku organicznego. Funkcję dodatku do kąpieli pełnił benzenosulfonian sodu (SBS). Strukturę, skład oraz właściwości powłok zbadano stosując SEM-EDS, mikroskop optyczno-cyfrowy, natomiast odporność na warunki korozyjne wykorzystując badania potencjału korozji w funkcji czasu oraz metodę potencjodynamiczną.

5

Investigation of shear stress distribution in a 90 degree channel bend

Lee S. K., Dang T. A., Le V. T.

International Journal of Applied Mechanics and Engineering

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2019

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Vol. 24, no. 1

213--220

EN

Shear stress is a key parameter that plays an important role in sediment transport mechanisms; therefore, understanding shear stress distribution in rivers, and especially in river bends, is necessary to predict erosion, deposition mechanisms and lateral channel migration. The aim of this study is to analyze the shear stress distribution near a river bed at 90-degree channel bend using a depth-average method based on experimental measurement data. Bed shear stress distribution is calculated using the depth-averaged method based on velocity components data has been collected from a 3D-ADV device (three-dimensional acoustic doppler velocity) at different locations of a meandering channel. Laboratory experiments have been made at the hydraulic laboratory of the RCRFIDF (Research Center for River Flow Impingement and Debris Flow), Gangneung-Wonju National University, South Korea to provide data for simulating the incipient motion of the riverbed materials and then predicting the river morphological changes in the curved rivers. The calculated results show that the maximum value of shear stress distribution near the riverbed in the different cross sections of the surveyed channel occurs in a 70-degree cross section and occurs near the outer bank. From the beginning of a 40-degree curved channel section, the maximum value of the shear stress occurs near the outer bank at the end of the channel.

6

What can be learned about the deposition and compaction of peat from the Miocene lignite seam exposed in the Chłapowo Cliff on the Polish coast of the Baltic Sea?

Widera Marek

Geology, Geophysics and Environment

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2019

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Vol. 45, no. 2

111--119

EN

This study focuses on discussing the relationship between the accumulation of peat and its compaction in the overbank zone of the Miocene river system. The examined 2nd Lusatian lignite seam is characteristically interbedded with sandy deposits and these are less compressible than peat. Therefore, in favourable conditions such as those found at Chłapowo Cliff (on the Baltic Sea coast in northern Poland), it is possible to identify the effects of an even or uneven lowering of the mire surface, resulting from diversified compaction of the underlying phytogenic beds. The research problem was applied to two examples located close to each other within the lignite seam. The first case shows the accumulation of fresh peat layers of almost equal thickness, while the second one presents a reduction in the thickness of fresh peat beds over the fossilised channel-fill sandy body. Only the latter example allows us to calculate the peat-to-lignite compaction ratio. The results of the compaction ratio obtained, Cr ≈ 7.37, mean that the youngest, fresh peat layers were compacted at least 7 times, transforming them into lignite beds. However, such a high compaction value, estimated for the top layers of the Miocene mire, cannot be directly taken into account when reconstructing the total thickness of the peat seam prior to covering it with mineral overburden. The published peat-to-lignite compaction ratios, determined using other research methods, for the 2nd Lusatian lignite seam or its stratigraphic equivalents range from 1.7 to 6.0 in most cases, with averages of 2.2 to 4.0. The differences between the data in the literature and the results given in this paper are due to the fact that the process of peat/lignite compaction is ongoing and cumulative.

7

Impact of thermophoretic transport of Al2O3 nanoparticles on viscoelastic flow of oil-based nanofluid over a porous exponentially stretching surface with activation energy

Etwire Christian John, Seini Ibrahim Yakubu, Musah Rabiu, Makinde Oluwole Daniel

Engineering Transactions

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2019

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Vol. 67, iss. 3

387--410

EN

The influence of thermophoretic transport of Al2O3 nanoparticles on heat and mass transfer in viscoelastic flow of oil-based nanofluid past porous exponentially stretching surface with activation energy has been examined. Similarity technique was employed to transform the governing partial differential equations into a coupled fourth-order ordinary differential equations which were reduced to a system of first-order ordinary differential equations and then solved numerically using the fourth-order Runge-Kutta algorithm with a shooting method. The results for various controlling parameters were tabulated and graphically illustrated. It was found that the thermophoretic transport of Al2O3 nanoparticles did not affect the rate of flow and heat transfer at the surface but it affected the rate of mass transfer of the nanofluid which decayed the solutal boundary layer thickness. This study also revealed that activation energy retards the rate of mass transfer which causes a thickening of the solutal boundary layer.

8

Effect of pulsed magnetron sputtering process for the deposition of thin layers of nickel and nickel oxide

Posadowski W., Wiatrowski A., Kapka G.

Materials Science Poland

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2018

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Vol. 36, No. 1

69--74

EN

Magnetron sputtered nickel and nickel oxide films have been studied for various applications. We may find, among others, these films in electrochromic display devices, in resistive type gas sensors, as metal electrodes in electronic devices, in solar thermal absorbers. Pure nickel films deposited using PVD technique possess good corrosion and wear resistant properties. Magnetron sputtering has several advantages in film deposition (in comparison to other methods) such as relatively low heating temperature of the deposited substrate during sputtering process, high energy of sputtered atoms (about 10 eV) at the substrate, which influences positively the films adhesion. From application point of view, the most valuable feature of these films is the possibility of scaling target dimensions, which makes feasible the deposition on a several square meter surfaces. The improvement of magnetron sputtering devices design may influence positively the optimization of the deposition technology and its efficiency. The thin nickel and nickel oxide films were prepared by pulsed magnetron sputtering using original type WMK magnetron device. Ni (99.9 %) has been used as a sputtering target of 100 mm in diameter and different thicknesses (3 mm, 5 mm, and 6 mm). The distance between the substrate and target was the same in all experiments and equal to 120 mm. Argon and oxygen gases were introduced during the reactive process through needle gas valves at a total pressure of 0.4 Pa. The sputtering power, sputtering pressure and oxygen partial pressure have been used as technological knobs for deposition processes. The helpful tool for controlling the pulsed magnetron sputtering process was the original parameter of supply (so called circulating power). Results from our experiments showed that the deposition of Ni films is possible even from targets of 6 mm thickness. Deposition rate increased proportionally with the sputtering power. The aim of this work is to use the acquired expertise to develop an efficient technology of thin nickel oxide layers for electrochromic systems.

9

A review of radiometric analysis on soil erosion and deposition studies in Africa

Maina C. W., Sang J. K., Mutua B. M., Raude J. M.

Geochronometria

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2018

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Vol. 45, no. 1

10--19

EN

Soil erosion is one of the main soil degradation phenomena that threaten sustainable use of soil productivity thus affecting food security. In addition, it leads to reservoir storage capacity loss because of sedimentation. This not only affects water quantity but also water quality. Worldwide, annual loss in reservoir storage capacity due to sedimentation is 0.5 to 1%. Similarly, about 27% of land in Africa is largely degraded by erosion. As a result, there is need to minimize soil erosion and deposition through site specific estimation of soil erosion and deposition rates in the reservoirs. To achieve this, Fallout RadioNuclides (FRNs) are some of the methods in use. The most common radionuclides include; 137Cs, 210Pb and 7Be. Only few countries in Africa have exploited these FRNs. In these countries, 137Cs has been largely exploited but in some regions, it has been reported to be below minimum detection limit. Using 137Cs and 210Pb, maximum reference inventory in Africa is found to be 1450 and 2602 Bq/m2, respectively. However, there is minimal application of 7Be within the continent. Also, very little has been done in Africa to assess chronology and sedimentation rates of reservoirs using FRNs measured from sediment cores. In conclusion, a gap still exists on FRNs application in Africa in assessing soil erosion, deposition and reservoir sedimentation.

10

Effect of the cement and limestone industry on the chemical properties of water beneath tree canopies

Sporek Monika

Ecological Chemistry and Engineering. A

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2018

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Vol. 25, nr 2

207--214

EN

This study is a continuation of earlier research aimed at determining the changes in the quality of precipitation beneath the canopy in pine stands affected by the emission of alkaline pollutants. This study was conducted in the Gorazdze Forest District, in a forest complex in south-western Poland affected by the cement and limestone industry. The rainwater measurements under the canopy of Scots pine were made according to the methodology of the environmental monitoring. Wet and dry deposits, thus the total pollution load brought into the forest ecosystem, were analysed. The pH and electrical conductivity was measured in collected water samples. The results showed differences between precipitation in winter (1.10–31.03 next year; fourth and first quarters), and in the growth season (during the second and third quarters – 1.04–30.09). Precipitation sampled beneath tree canopies in the winter half year had higher pH than those from the growth season half year (Table 2).

PL

Prowadzone badania są kontynuacją wcześniejszych prac, których celem jest określenie dynamiki zmian jakości wód opadowych pod okapem drzewostanów sosnowych, znajdujących się pod wpływem imisji zanieczyszczeń alkalicznych. W pracy przedstawiono wyniki trzyletniego okresu badawczego, obejmującego lata 2015–2017. Badania prowadzono w kompleksie leśnym w południowo-zachodniej części Polski (Leśnictwo Górażdże), będącym pod wpływem przemysłu cementowo-wapienniczego. Pomiary wody deszczowej pod okapem sosny zwyczajnej wykonano zgodnie z metodologią monitoringu środowiska Analizie podlegał zarówno depozyt mokry jak i suchy, czyli łączny ładunek zanieczyszczeń jaki wnoszony jest do ekosystemów leśnych. W pobranych próbach wody oznaczono odczyn (pH) oraz przewodnośæ elektrolityczną. Trzyletnie badania wykazały znaczne zróżnicowanie odczynu i przewodności elektrolitycznej opadów atmosferycznych. Uzyskane wartości pH mieściły się w przedziale 3,54–7,97 (tab. 1). Wyniki badań wskazują na różnicę między opadami zimowymi (1.10–31.03 następnego roku IV i I kwartał) a opadami w okresie wegetacyjnym (1.04–30.09; II i III kwartał). Opady podokapowe półrocza zimowego miały wyższy odczyn niż w miesiącach przypadających na okres wegetacyjny (tab. 2).

11

Metanizacja CO₂ na katalizatorach wytworzonych metodą depozycji plazmowej

Tracz P., Redzynia W., Kierzkowska-Pawlak H., Tyczkowski J.

Przemysł Chemiczny

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2017

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T. 96, nr 3

672--674

PL

Przedstawiono wyniki badań metanizacji CO₂ przy użyciu nanokatalizatorów wytworzonych na kantalowych nośnikach strukturalnych za pomocą metody chemicznej depozycji z par związków metaloorganicznych wspomaganej plazmą (PEMOCVD). Wykazano wysoką aktywność katalityczną wytworzonych nanowarstw w reakcji uwodornienia CO₂ do metanu. Na podstawie przeprowadzonych badań stwierdzono możliwość wykorzystania przemysłowego wytworzonych katalizatorów, szczególnie w reaktorach strukturalnych.

EN

New Co and Ru nanocatalysts for methanation of CO₂ were prepd. by plasma-enhanced metal-org. CVD on metallic structural supports. The Co₃O₄ or RuO₂-contg. thin films of the nanocatalysts were used for conversion of CO₂ with H₂ (mole ratio 1:4) to MeH in a gradientless flow reactor at 150-500°C and atm. pressure. The exptl. results revealed a high catalytic activity of the deposited films. The RuO₂ catalyst showed higher activity than the Co₃O₄ one.

12

Peculiarities of simulation of the additive process of forming of 3D products from steel 09G2S

Grigorenko G. M., Kostin W. A., Mossokovskaya I. A.

Przegląd Spawalnictwa

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2017

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R. 89, nr 9

42--48

EN

The results of modeling of thermal fields, stresses, deformations and displacements in formation of an additive structure of 09G2S steel on a substrate are presented. An interdisciplinary research computational package COMSOL Multiphysics was used for computer modeling. Effect of the temperature on physicochemical parameters of steel was taken into account in the work. The results for modeling were obtained using Gleeble 3800 a complex for simulation of thermal deformation state of welding thermal cycle. Some physical-thermal properties of 09G2S steel were calculated using JmatPro 6.0 software package. Carried investigation showed that the highest level of residual stresses and deformations in additive deposition of 09G2S steel layers on the substrate is reached at the boundary of the first layer and substrate and makes 280–320 MPa. Stresses between the layers of deposited metal are significantly lower (to 50 MPa). It is determined that the increase of the number of deposited layers provokes nonlinear rise of a level of stress at the additive layer/substrate boundary and does not depend on the number of deposited layers in time. In additive manufacturing process, preheating to at least 300÷320 °C temperature should be used to prevent noticeable deformation of the substrate. Developed software can be used for mathematical modeling of additive process of formation of steel, titanium and aluminum alloys structures.

PL

Przedstawiono wyniki modelowania pól termicznych, naprężeń, odkształceń i przemieszczeń przy formowaniu konstrukcji addytywnej ze stali 09G2S na podkładce. Dla dokonanego modelowania komputerowego wykorzystano pakiet dla międzydyscyplinarnych badań COMSOL Multiphysics. W pracy uwzględniono wpływ temperatury na parametry fizykochemiczne stali. Wyniki dla modelowania otrzymano z wykorzystaniem kompleksu imitowania stanu termo-odkształceniowego cyklu termicznego spawania Gleeble 3800. Właściwości fizyko-termiczne stali 09G2S obliczono za pomocą pakietu JmatPro 6.0. Przeprowadzone badania świadczą, że przy nanoszeniu addytywnym warstw stali 09G2S na podkład największy poziom naprężeń resztkowych i odkształceń osiąga się na granicy pierwszej warstwy i podkładki i stanowi 280÷320 MPa. Naprężenia miedzy warstwami metalu napawanego są znacznie niższe (do 50 MPa). Ustalono, że ze wzrostem ilości warstw naniesionych poziom naprężeń na granice warstwa addytywna/podkład wzrasta nieliniowo i z czasem nie zależy od ilości warstw nanoszonych. Przy procesie addytywnym dla zapobiegania odkształcenia podkładu należy stosować poprzednie nagrzewanie do temperatur 300÷320 °С. Te programy mogą być stosowane dla modelowania matematycznego procesu formowania konstrukcji ze stali i stopów aluminiowych.

13

Deposition of spray liquid depending on the coefficient of spray surfaces

Cieniawska B., Łuczycka D., Červinka J., Sekutowski T. R., Dereń K.

Journal of Research and Applications in Agricultural Engineering

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2017

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Vol. 62, nr 3

72--75

EN

In the assessment of the quality of treatment using the application indicator there is no information concerning the parametric characteristics of the sprayed plant. Therefore, the aim of this study was to determine the application of the utility liquid depending on the coefficient of the position of the spray surfaces with the use of the selected single- and dual- spray nozzles. The studies were performed at the Institute of Agricultural Engineering of the University of Environmental and Life Sciences in Wroclaw, in laboratory conditions. The carrier of nozzles acting as an independent sprayer was used for spraying. The coefficient of the position of the spray surfaces as the relation of surfaces of vertical projections and to the surfaces of horizontal projections was determined using artificial plants by appropriately setting its sprayed surfaces. Results of the tests and their analysis showed the influence of the position of spray surfaces coefficient on the deposit of the spray liquid.

PL

W ocenie jakości zabiegu z wykorzystaniem wskaźnika naniesienia brakuje informacji dotyczącej parametrycznej charakterystyki opryskiwanej rośliny. Dlatego też celem pracy było określenie naniesienia cieczy użytkowej zależności od współ- czynnika położenia powierzchni opryskowych z zastosowaniem wybranych rozpylaczy jedno i dwustrumieniowego. Badania wykonano w Instytucie Inżynierii Rolniczej Uniwersytetu Przyrodniczego we Wrocławiu, w warunkach laboratoryjnych. Do opryskiwania użyto nośnika rozpylaczy działającego jak samodzielny opryskiwacz. Współczynnik położenia powierzchni opryskowych jako stosunek powierzchni rzutów pionowych i do powierzchni rzutów poziomych określano z zastosowaniem sztucznych roślin odpowiednio ustawiając jej opryskiwane powierzchnie. Wyniki badań i ich analiza wykazały wpływ współczynnika powierzchni opryskowych na wielkość naniesienia cieczy użytkowej.

14

The physical and mechanical properties of (Ti, Hf, Zr, Nb, V, Ta) N coatings deposited in the vacuum-arc process

Tleukenov Y. O., Pogrebnjak A. D., Plotnikov S. V., Erdybaeva N. K.

Tribologia

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2016

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nr 5

195--207

EN

Nitride nanostructured coatings, which are based on high entropy alloys implanted with high doses of N + ions to 10X18 cm2 with an energy of 60 KeV were investigated. The coatings were deposited by vacuum circuit-arc method of cathode evaporation on steel samples when applying different potential on the steel substrate and the residual pressure in the chamber. The chamber was supplied by molecular nitrogen for nitride formation. Several methods such as SIMS, EDS, and XRD were used for elemental composition analysis of the coating. A scanning electron microscope with energy dispersive spectrometry was used in order to study the surface of the multi-component coatings and their elemental composition and distribution of elements on the surface coating. Nanohardness and elastic modulus were studies in dynamic mode at Triboindentor. Introduction of N atoms into the lattice led to the formation of solid solution. Nanostructured coatings obtained by vacuum-arc deposition with high micro-strain action show high hardness values (up to 32 GPa) due to the difference in atomic radius of the crystal lattices metal components. The coefficient of friction was in the range of 0.18 to 0.25. Deposited nanostructured films with the given mechanical properties may be used for wear resistant or protective coatings.

PL

Przebadano nanostrukturalne powłoki azotków o wysokiej entalpii, które wytworzono z wykorzystaniem implantacji jonami N+ przy zastosowaniu dużych gęstości jonów 10x18 cm2 i wysokiej energii 60 keV. Powłoki osadzano łukową metodą próżniową na próbkach ze stali, stosując zróżnicowany potencjał polaryzacji podłoża oraz zróżnicowane ciśnienie azotu w komorze. Do badań składu chemicznego powłoki zastosowano następujące metody: RBS, SIMS, EDS i XRD. Skaningowy mikroskop elektronowy z dyspersją energii zastosowano do badania powierzchni powłok wieloskładnikowych i ich składu chemicznego i rozmieszczenia pierwiastków na przekroju powłoki. Do badania nanotwardości i modułu sprężystości wykorzystano Triboindentor. Badania wykazały, że wprowadzenie atomów N do sieci krystalicznej powłoki prowadzi do tworzenia roztworu stałego. Po-włoka nanostrukturalna uzyskana łukową metodą próżniową charakteryzuje się wysoką twardością (do 32 GPa) ze względu na wysoki stan naprężeń wywołany różnicą średnic atomowych pierwiastków składowych powłoki. Współczynnik tarcia powłoki jest w zakresie od 0,18 do 0,25. Osadzone nanostrukturalne powłoki o dobrych właściwościach mechanicznych mogą być stosowane jako odporne na zużycie powłoki ochronne.

15

Core-shell SiO2/Ag composite spheres: synthesis, characterization and photocatalytic properties

Wu Z. G., Jia Y. R., Wang J., Guo Y., Gao J. F.

Materials Science Poland

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2016

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Vol. 34, No. 4

806--810

EN

Core-shell SiO2/Ag composite spheres with dense, complete and nanoscaled silver shell were prepared by using a novel facile chemical reduction method without surface modification of silica at room temperature. The core-shell composites were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), UV-Vis spectroscopy and energy dispersive X-ray spectroscopy (EDX). The photocatalytic properties towards the degradation of methyl orange (Mo) of the prepared SiO2//Ag composites were also tested. The studies showed that the surface of SiO2/ microspheres was homogeneously and completely covered by Ag nanoparticles and the composite exhibited excellent photocatalytic activities. The possible reaction mechanisms for the formation of the silica-silver core-shell spheres were also discussed in this paper.

16

Sediment transport modelling in wadi Chemora during flood flow events

Berghout A., Meddi M.

Journal of Water and Land Development

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2016

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no. 31

23--31

EN

The sediment transport is a complex phenomenon by its intermittent nature, randomness and by its spatiotemporal discontinuity. By reason of its scale, it constitutes a major constraint for development; it decreases storage capacity of dams and degrades state of ancillary structures. The study consists in modelling the transport of sediments by HEC-RAS software in wadi Chemora (Batna, Algeria). In order to do this, we have used hydrometric data (liquid flows, and solid flows) recorded at level of the four hydrometric stations existing in watershed of wadi Chemora, the MNT of the wadi and lithologic characteristics of the wadi. In the analyses of results we used the parameters from two different floods (the first one involved the whole watershed and the second – a part of the basin) along of system of wadi Chemora (wadi Chemora and its tributaries): sediment transport capacity, volume of sediments delivered to and leaving the system and areas sensitive to erosion and sedimentation.

PL

Ruch rumowiska jest zjawiskiem złożonym ze względu na jego nieciągły charakter oraz losowe, zmienne w czasie i przestrzeni warunki transportu. Ze względu na swoją skalę stanowi on główne ograniczenie rozwoju, zmniejsza pojemność zbiorników wodnych oraz pogarsza stan innych budowli wodnych. W pracy przedstawiono wyniki modelowania transportu rumowiska w uedzie Chemora (Batna, Algeria) za pomocą programu HEC-RAS. W tym celu wykorzystano dane hydrometryczne (przepływu wody i transportu rumowiska) zarejestrowane w czterech przekrojach wodowskazowych zlokalizowanych w zlewni rzeki Chemora, dane z Numerycznego Modelu Terenu (NMT) zlewni oraz charakterystyki litologiczne koryta. Do analizy wyników modelowania wykorzystano parametry zarejestrowane w czasie dwóch wezbrań powodziowych w rzece Chemora (pierwsze wystąpiło w całej zlewni, drugie – w jej części), takie jak: objętość transportu rumowiska, początkowa objętość rumowiska (na wejściu do systemu) i końcowa (na wyjściu z systemu) oraz miejsca narażone na erozję i akumulację rumowiska.

17

Growth and Characterisation of Pulsed-Laser Deposited Tin Thin Films on Cube-Textured Copper at Different Temperatures

Szwachta G., Gajewska M., Kąc S.

Archives of Metallurgy and Materials

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2016

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Vol. 61, iss. 2B

1031--1038

EN

High-quality titanium nitride thin films have been grown on a cube-textured copper surface via pulsed laser deposition. The growth of TiN thin films has been very sensitive to pre-treatment procedure and substrate temperature. It is difficult to grow heteroexpitaxial TiN films directly on copper tape due to large differences in lattice constants, thermal expansion coefficients of the two materials as well as polycrystalline structure of substrate. The X-Ray diffraction measurement revealed presence of high peaks belonged to TiN(200) and TiN(111) thin films, depending on used etcher of copper surface. The electron diffraction patterns of TiN(200)/Cu films confirmed the single-crystal nature of the films with cube-on-cube epitaxy. The high-resolution microscopy on our films revealed sharp interfaces between copper and titanium nitride with no presence of interfacial reaction.

18

Adhesivity of electroless Ni-P layer on austenitic stainless steel

Smoljan B., Iljkić D., Maretić M.

Archives of Materials Science and Engineering

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2016

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Vol. 80, nr 2

53--58

EN

Purpose: Optimization of testing of adhesivity of electroless deposited nickel-phosphorous coatings on austenitic stainless steel substrate. Design/methodology/approach: The main study has been focused on comparison of testing methods of adhesivity of electroless nickel-phosphorous coatings and analyses of influence of heat treatment on adhesivity of electroless nickel-phosphorous. Findings: It was found out that adhesivity of electroless nickel-phosphorous coatings can be successfully characterized by Vickers hardness tester. Research limitations/implications: The study was not extended to other types of deposited layers in order to be able to bring a general decision about applicability of this method in the testing of adhesivity of deposited layers. Practical implications: Based on experimental results it was found out that heat treated nickel-phosphorous coating have higher microhardness than non-heat treated electroless nickel-phosphorous coatings. High microhardness of heat treated nickel-phosphorous coating is connected with formation of Ni3P phase. Moreover, better adhesivity can be achieved by application of proper activation process before electroless coating. Originality/value: Standard Vickers hardness method was successfully applied in testing of adhesivity of electroless nickel-phosphorous coatings on austenitic stainless steel substrate.

19

Influence of Experimental Conditions on Deposition of Silver Nanoparticles Onto Surface of Graphene Oxide

Wojnicki M., Mania I., Marzec M., Gajewska M., Mech K.

Archives of Metallurgy and Materials

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2015

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Vol. 60, iss. 4

2631--2636

EN

Present work describes the influence of silver nanoparticles precursor form as well as the impact of graphene oxide initial concentration on deposition of the silver nanoparticles onto graphene oxide. Borane dimethylamine complex (DMAB) was used as the reducing agent. It was observed that application of silver ammonia complexes as the silver nanoparticles precursor as well as alkaline solution effect in higher quantity of deposited AgNPs in comparison to deposition process with the use of silver(I) nitrate in acidic solution.

PL

Praca przedstawia wyniki badań nad wpływem wybranych parametrów na proces syntezy i osadzania nanocząstek srebra na powierzchni tlenku grafenu. W badaniach uwzględniono wpływ następujących czynników: stężenie początkowe tlenku grafenu, stężenie początkowe prekursora oraz jego rodzaju. Jako reduktor jonów Ag(I) zastosowano dimetyloamino boran (DMAB). Stwierdzono, iż zastosowanie kompleksu amoniakalnego srebra jako prekursora, jak również zastosowanieśrodowiska alkaicznego skutkuje wyższą efektywnością procesu osadzania AgNPs na powierzchni tlenku grafenu w porównaniu do procesu prowadzonego z zastosowaniem azotanu(V) srebra(I) w środowisku kwaśnym.

20

Synteza wielościennych nanorurek węglowych metodą katalityczno-chemicznego osadzania z fazy gazowej

Dobrzańska-Danikiewicz A., Cichocki D., Wolany W., Łukowiec D.

Inżynieria Materiałowa

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2014

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Vol. 35, nr 6

477--480

PL

Metoda katalityczno-chemicznego osadzania z fazy gazowej (CCVD) umożliwia syntezę wysokiej jakości wielościennych nanorurek węglowych na masową skalę. Można wyróżnić wiele zmiennych, które wpływają w trakcie syntezy na rodzaj i postać produktu finalnego. Celem artykułu jest wyznaczenie najkorzystniejszych parametrów procesu syntezy wielościennych nanorurek węglowych metodą katalityczno-chemicznego osadzania z fazy gazowej przez odpowiedni dobór temperatury i czasu procesu syntezy oraz prędkości przepływu wodoru. Zmienne te wstępnie wyselekcjonowano jako najistotniej wpływające na postać i jakość wytworzonego nanomateriału węglowego. Do obrazowania struktury i morfologii nowo wytworzonych wielościennych nanorurek węglowych wykorzystano skaningową mikroskopię elektronową i transmisyjną mikroskopię elektronową. Badanie stopnia zdefektowania wytworzonych nanorurek węglowych wykonano metodą spektroskopii ramanowskiej.

EN

Catalytic Chemical Vapor Deposition (CCVD) method allows for the synthesis of high-quality multiwall carbon nanotubes on a mass scale. A number of variables that affect the course of the synthesis of the type and the form of the final product can be distinguished. The purpose of this paper is to present an approach for the optimisation of the synthesis process of multiwall carbon nanotubes by Catalytic Chemical Vapor Deposition by appropriately selecting the temperature and time of the synthesis process and the hydrogen flow rate. These variables are pre-selected as one which the most influencing on the character and quality of the produced carbon nanomaterial. To image the structure and the morphology of the newly formed multiwall carbon nanotubes scanning electron microscopy and transmission electron microscopy have been used. Research purity and the degree of defecting of produced carbon nanotubes were made using Raman spectroscopy.