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1
EN
The article presents the results of the preliminary research of tribological properties of flame sprayed nickel and aluminum coatings reinforced with carbon nanotubes made on the structural steel S235J0 substrate. The carbon material – carbon nanotubes Nanocyl NC 7000 (0.5 wt.% and 1 wt.%) was used for structural reinforcement. The properties evaluation was made by the use of optical microscopy, scanning electron microscopy, Raman spectroscopy, microhardness measurements, and by means of abrasion and erosion resistance laboratory tests. The obtained results were compared with pure nickel powder coatings 2N5 (Ni 99.5%) and with pure aluminum powder coatings (EN AW 1000 series). It was proved that the flame spraying of nickel and aluminum coatings reinforced with particles carbonaceous material can be an effective alternative for other more advanced surfacing technology. The preliminary test results will be successively extended by further experiments to contribute in the near future to develop innovative technologies, that can be implemented in the aviation industry and the automotive. The presented research is a continuation of the work previously published.
2
Content available remote Gazy osłonowe do spawania niklu, kobaltu i ich stopów
PL
W artykule omówiono rodzaj i skład gazów używanych podczas spawania niklu, kobaltu i ich stopów, jak również opisano wpływ poszczególnych gazów na proces spawania i jakość złączy spawanych.
EN
The type and composition of gases used in welding of nickel, cobalt and their alloys are discussed, as well as the influence of shielding gases on welding process and quality of welded joints are described.
4
Content available remote Nickel comb capacitors for real-time monitoring of cancer cell cultures
EN
The work is devoted to the technology of biocompatible substrates with nickel electrodes for in vitro impedance cell culture studies. The legitimacy of this subject was tested by conducting measurements using a system based on the Electric Cell-Substrate Impedance Sensor method. A device for cell bioimpedance testing, made in thin-film technology, has been described. Parameters and applications of the material used for construction, which is commonly used nickel, are discussed. The results of preliminary studies on melanoma cancer cells from the A375 cell line were presented, during which the already used measurement matrices were used. An analysis of the observed changes and obtained results was carried out.
PL
Praca poświęcona jest technologii biokompatybilnych podłoży z niklowymi elektrodami do badań impedancji hodowli komórek in vitro. Zasadność podjęcia tej tematyki przetestowano przeprowadzając pomiary przy użyciu systemu opartego na metodzie ECIS (ang. Electric CellSubstrate Impedance Sensor). Opisano przyrząd służący do badań bioimpedancji komórek, wykonany w technologii cienkowarstwowej. Omówiono parametry i zastosowania wykorzystanego do budowy urządzania materiału, którym jest powszechnie stosowany nikiel. Przedstawiono wyniki wstępnych badań nad komórkami nowotworowymi czerniaka z linii komórkowej A 375, do których użyto wykonane matryce pomiarowe. Dokonano analizy zaobserwowanych zmian i otrzymanych rezultatów.
EN
Reactive oxygen species (ROS) include both oxygen free radicals and highly reactive oxygen compounds (such as ozone, singlet oxygen). They are formed in many metabolic processes, as well as under the influence of various environmental factors. Their impact on cells depends on their concentration and the duration of the process. Excessive level of ROS in a cell leads to oxidative stress. One of the defence mechanisms against ROS corresponds to antioxidant enzymes including SOD and CAT. This paper defines the changes in the activity of antioxidant enzymes caused by oxidative stress induced by nickel and paraquat in tissue of Acheta domesticus L, derived from various development lines. The obtained results defining the activity of SOD and CAT indicated the differences among individual tissues and the midgut showed the highest activity. Increased activity in relation to the control group results of CAT and SOD in the midgut and fat body of B-line individuals treated with pro-oxidant (particularly nickel) and inhibition of the CAT activity in the midgut of L-line crickets influenced by pro-oxidant indicate that the conducted screening changes the biochemical response to the stress factors. Moreover, the obtained results may indicate the relation of the activity of SOD and CAT with the lifespan of the tested insects.
EN
The aim of the study was to present a method for assessing the condition of cell culture by measuring the impedance of cells cultured in the presence of nickel. For this purpose, an impedance measurement technique using nickel comb capacitors was used. The capacitor electrodes were made using a thin film magnetron sputtering. In the experimental part, the culture of cells of mouse fibroblasts on the prepared substrate was performed. The cell culture lasted 43 hours and showed that the presented technique allows it to be used to analyze the effect of nickel on cells.
PL
Celem pracy było przedstawienie metody oceny stanu hodowli komórkowej poprzez pomiar impedancji komórek hodowanych w obecności niklu. W tym celu zastosowano technikę pomiaru impedancji z wykorzystaniem niklowych kondensatorów grzebieniowych. Cienkowarstwowe elektrody kondensatora wykonano metodą rozpylania magnetronowego. W części eksperymentalnej przeprowadzono hodowlę komórek mysich fibroblastów na przygotowanym podłożu. Hodowla komórkowa trwała 43 godziny i wykazała, że przedstawiona technika mogłaby być zastosowana do analizy wpływu niklu na komórki.
EN
Saccharomyces cerevisiae, waste biomass originated from beer fermentation industry, was used to remove metal ions from four copper-containing synthetic effluents: Cu-Fe, Cu-Fe-Ni, Cu-Fe-Zn, and Cu-Fe-Ni-Zn. The characterization of the biomass surface was investigated by Scanning Electron Microscopy and Fourier-transform Infrared Spectroscopy. The adsorption behavior of Saccharomyces cerevisiae for copper, iron, nickel and zinc ions in aqueous solution was studied as a function of pH, initial copper concentration, equilibrium time, and temperature. Langmiur, Freundlich, Temkin and Dubinin-Radushkevich equilibrium models have been assessed to describe the experimental sorption equilibrium profile, while pseudo-first order, pseudo-second order, Elovich and the intra-particle diffusion models were applied to describe experimental kinetics data. Maximum sorption capacities have been calculated by means of Langmuir equilibrium model and mean free sorption energies through the Dubinin-Radushkevich model. Thermodynamic analysis results showed that the adsorption of copper, iron and zinc was spontaneous and endothermic in nature, while of nickel exothermic. Saccharomyces cerevisiae can be successfully applied for complex wastewater treatment.
8
Content available remote Gazy osłonowe do spawania metodą MIG/MAG. Cz. I
PL
W artykule omówiono rodzaj i skład gazów osłonowych używanych podczas spawania metodą MIG/MAG, jak również wyjaśniono powody występowania różnic w ich składzie w zależności od materiału spawanego i obszaru stosowania.
EN
The type and composition of shielding gases used in MIG/MAG welding are discused, as well as the reasons for the differences in their composition depending on the parent material and field of applications are explained.
EN
Base metals (Cu, Zn and Pb) as the main resources of the Lower Silesian copper deposits have significantly been influenced by different enviromentalfactors. In this paper, changes in metal concentrations on the surface in relation to deeper layers of the sediments were examined. The concentration ofmetals in the whole sediment, and in selected grain fractions was studied. The contents of these metals in the soils of areas adjacent to the deposit are diverse and are in the range of: 3.0-1082.9 mg/kg Cu; 3.5-106.1 mg/kg Pb; 27.6-49.3 mg/kg Zn, and 1.33-23.0 mg/kg Ni in the old deposit district and Cu 0.91-1655.0 mg/kg Pb; 10.0-1792.0 mg/kg Zn; 3.38-1129.0 and 0.47-32.7 mg/kg Ni in the new deposit district. The increase of metal concentration in the finefractions has been observed. Moreover, the decrease in the metal content with depth was observed in all investigated profiles.
EN
Sulphuric acid leach solution of waste printed circuit boards (PCBs) contains predominantly copper and iron with later remain problematic during electrowinning of the formal. In this study, performance of Dowex M 4195 resin for recovery of copper and nickel from polymetallic sulphate leach solution of waste PCBs was investigated by batch experiments. It was observed that at pH 0.5, about 45.2 and 3.6 % Cu2+ and Ni2+ was selectively recovered respectively. Recovery efficiency of Ni2+ increased with increase in pH from 0.5 -5.0 while pH2 was optimum for the recovery of Cu2+. Sharp increase in co-recovery of Fe3+/Fe2+ was observed at pH above 2 with that of Zn2+ and Co2+ became low due to hindrance from binding site by high concentration of Cu2+. Adsorption data obtained for Cu2+ and Ni2+ were tested with adsorption isotherms as well as kinetics. It is shown that adsorption of Cu2+ and Ni2+was well fitted to both Langmuir and Freundlich isotherm. Kinetics of Cu2+ and Ni2+ fitted into Pseudo-first and well fitted to second order. Reuse studies shows that the resin strong affinities for Cu2+ and Ni2+ remain unchanged.
EN
Large scale production of hydrogen by water electrolysis needs effective electrodes made from cheap earth - abundant materials. Widely used are nickel electrodes whose effectiveness can be improved by carbon materials, including graphene and graphene oxide (GO). In this work, electrodeposits of nickel (Ni) and of nickel with GO (Ni/GO) were obtained from the Watts solution without and with GO, respectively. Ni deposits were flat, whereas Ni/GO deposits had cauliflower morphology with developed surface area. Electrochemical behaviour was examined in 0.1 M Na2SO4 . In comparison with Ni, Ni/GO showed higher corrosion rate, higher anodic polarization currents, and higher cathodic hydrogen evolution reaction (HER). Voltammetric cycling to potentials of passivation caused a rise in HER for both materials, but for Ni/GO it was significantly higher. Enhanced HER on Ni/GO was explained mainly by the formation of larger amounts of catalytically active Ni oxides/hydroxides.
PL
Do wytwarzania wodoru w dużej skali przez elektrolizę wody potrzebne są wydajne elektrody z materiałów tanich i obficie występujących na Ziemi. Szeroko stosowane są elektrody niklowe, których sprawność może być poprawiona przez materiały węglowe, włączając grafen i tlenek grafenu (GO). W niniejszej pracy, warstwy niklu (Ni) i niklu z GO (Ni/GO) otrzymywano przez elektroosadzanie z roztworu Watts’a bez i z GO. Warstwy Ni były gładkie, natomiast warstwy Ni/GO miały morfologię typu kalafiora z rozwiniętą powierzchnią. Zachowanie elektrochemiczne badano w 0,1 M Na2SO4. W porównaniu z Ni, Ni/GO wykazywało większą szybkość korozji, większe prądy polaryzacji anodowej i większy katodowy prąd reakcji wydzielania wodoru (RWW). Woltamperometria cykliczna (VA) do potencjałów pasywacji powodowała wzrost RWW na obu materiałach, ale na Ni/GO był on znacznie większy. Zwiększony prąd RWW na Ni/GO wyjaśniono głównie tworzeniem większych ilości katalitycznych tlenków/wodorotlenków niklu.
EN
The publication presents the results of the research on the nickel content in potato tubers and green mass of fodder sunflower grown on a constant fertilization field on lessive soil developed from the loess located at the Rzeszów Foothills. The experiment established by randomized block design used a four-year crop rotation, which included potatoes, spring barley, fodder sunflower, and winter wheat. Mineral NPK fertilization was used on a background of constant Mg as well as Ca and Mg fertilization (liming). The nickel content in crops was determined by means of FAAS technique (Hitachi, Z 2000) after samples digestion in a mixture of HNO3:HClO4:H2SO4 at 20:5:1 ratio. A decrease of the nickel concentration in potato tubers and in green matter of fodder sunflower due to liming was observed. Mineral nutrition (regardless of liming) did not considerably affect the element content in potato tubers, yet it was significant for the metal content in green mass of sunflower. It was shown that the interaction of liming treatment with mineral fertilization contributed to the lowering of nickel concentration in test crops, especially in the green matter of the fodder sunflower (most of limed fertilization objects), while in potato tubers – to a lesser extent.
PL
Elementem odróżniającym Jezioro Licheńskie od zdecydowanej większości innych zbiorników wodnych - zarówno naturalnych, jak i sztucznych - jest zrzut podgrzanych wód z elektrowni konińskich. Bezsprzecznie wpływa on na pojawianie się gatunków obcych, a dodatkowo może być czynnikiem odgrywającym istotną rolę w przemianach metali ciężkich, zachodzących zarówno w toni wodnej, jak i w osadach. W badanej wodzie oznaczono metodą kolorymetryczną miedź, nikiel i ołów, a także pH i temperaturę. Zawartość metali ciężkich była wyższa w porównaniu do innych akwenów, co świadczy o dodatkowym ryzyku degradacji jeziora. Zrzut podgrzanej wody z elektrowni Konin niewątpliwie wpływa na pojawienie się obcych gatunków, a dodatkowo może być czynnikiem odgrywającym ważną rolę w przemianie metali ciężkich, występującej zarówno w wodzie, jak i w osadach. Na podstawie przeprowadzonych badań zawartości metali ciężkich, a także pH i temperatury można stwierdzić, że Jezioro Licheńskie pozostaje pod silną antropopresją. Świadczy o tym m.in. stosunkowo wysoka w porównaniu z innymi akwenami zawartość metali ciężkich, co stanowi dodatkowe zagrożenie degradacji biologicznej zbiornika.
EN
The element distinguishing the Licheńskie Lake from the vast majority of other water reservoirs - natural as well as artificial - is the discharge of heated water from the Konin power generation plants. It undeniably contributes to the occurrence of foreign species and may be an element playing an important role in heavy metal conversion taking place in the water and in the sediments. A study was carried out, measuring the content copper, nickel and lead, as well as pH and temperature of the water using the colometric method. The content of heavy metals was higher compared to other reservoirs, which constitutes an additional risk of the lake degradation. The discharge of heated water from the Konin power generation plant contributes to the occurrence of foreign species and it additionally may be a factor playing an important role in the heavy metals conversion, taking place in the water, as well as in the sediments. The results of measurements of the heavy metal content, pH and temperature indicate that the Licheńskie Lake is under strong anthropopressure. It is confirmed by a relatively high, compared to other reservoirs, content of heavy metals, which constitutes an additional risk of the reservoir’s biological degradation.
EN
The article presents results of studies on metal resistance to erosive damage taking place under the influence of hydraulic cavitation. On the basis of earlier research, a hypothesis on fatigue character of erosive wear and a dependence of metal resistance to erosive damage on its crystalline lattice structure has been assumed. To verify this hypothesis, metals with different crystalline lattice structures like steel 45 (flat-centred structure), nickel 200/201 and nickel alloy Monel 400 (hexagonal structure) have been tested at a cavitation-strike stand. Results obtained there confirmed the assumed hypothesis, at the same time justifying the use of nickel protective coatings in fluid-flow machines.
PL
W artykule przedstawiono wyniki badań odporności metali na uszkodzenia erozyjne zachodzące pod wpływem kawitacji hydraulicznej. Na podstawie wyników wcześniejszych badań, przyjęto hipotezę o zmęczeniowym charakterze zużycia erozyjnego oraz zależności odporności metali na zniszczenia erozyjne od struktury ich sieci krystalicznej. Dla potwierdzenia przyjętej hipotezy na stanowisku kawitacyjno-udarowym sprawdzono metale z różnymi sieciami krystalicznymi: stal 45 (sieć płasko centralna), nikiel 200/201 oraz stop niklu Monel 400 (sieć heksagonalna). Otrzymane wyniki badań potwierdziły przyjętą hipotezę, wskazując tym samym na zasadność stosowania niklowych powłok ochronnych w maszynach przepływowych.
PL
Celem prezentowanych badań była ocena zagrożenia ze strony intensywnie zagospodarowanych przemysłowo i rolniczo obszarów Wrocławia dla wód podziemnych sąsiadujących z nimi terenów wodonośnych. Na skutek przeprowadzonych prac terenowych i laboratoryjnych zdiagnozowano potencjalne ryzyko związane z napływem wód o podwyższonych stężeniach jonów niklu i potasu. Dla metali tych wykonano model migracji masy w wodach podziemnych. Obejmował on okres 10 lat, zakładając charakter zanieczyszczenia incydentalny – niklem i ciągły – potasem, na obszarach poza terenami wodonośnymi. W wyniku prac modelowych wykazano, że w badanym okresie nie dojdzie do przemieszczenia się jonów niklu w kierunku terenów wodonośnych. Możliwa jest nawet redukcja stężeń tego metalu na skutek procesu sorpcji. W toku prac modelowych stwierdzono możliwość niewielkiego zwiększenia stężeń oraz migracji jonów potasu, szczególnie z sąsiadującego z terenami wodonośnymi cieku Zielona, nie stanowi ona jednak zagrożenia dla ujęć terenów wodonośnych Wrocławia.
EN
The aim of this study was to risk assessment from the intensely developed industrial and agricultural areas of Wroclaw for groundwater of neighboring water-bearing area. As a result of field and laboratory work, a potential risk connected with the inflow of waters with increased concentrations of nickel and potassium ions was diagnosed. For these metals mass transport model in groundwater was performed. It covered a period of 10 years assuming the incidental nature of nickel contamination and continuous potassium pollution. As a result of modeling works, it was shown that in the studied period there will be no transport of nickel ions in the aquifer towards waterbearing area. It is even possible to reduce the concentrations of this metal due to the sorption process. During the modeling was identified also possible increase of concentration and migration of potassium ions, especially from the Zielona stream, however, it is not a threat to the water intakes of Wrocław.
EN
FeCl3 bearing etching solution is mainly used for etching of metals used in shadow masks, PCBs and so on. Due course of Invar alloy etching process the FeCl3 bearing etching solution get contaminated with Ni2+ which affect adversely the etching efficiency. Hence, FeCl3 bearing etching solution discarded after several cycle of operation causes an environmental and economic problem. To address both the issues the etching solution was purified through solvent extraction and remained Ni2+ recovered by wet chemical reduction using hydrazine. For optimum Fe3+ extraction efficiency, various extraction parameter were optimized and size and morphology of the recovered pure Ni powder was analyzed. The reported process is a simple process to purify and recover Ni from industry etching solution.
17
EN
In this paper researches which focus on laser heat treatment of nickel-based alloys are reviewed. Studies published from 1970s until today are taken into consideration. Publications which focus on influence of laser thermal processing on surface layer condition both on solid materials and predeposited coatings are described. Laser technologies in which additional materials are delivered during the process are not considered. In order to focus on studies investigating microstructural changes resulting mainly from material remelting, laser shock processing is also disregarded.
EN
Three types of sintered alloys were fabricated based on cobalt, nickel and high-temperature alloy ZhS32-VI matrix with titanium carbide strengthening phase. TiC content was in a range of 30–50 vol. %. The melting temperatures of alloys are higher than 1320°C, and they may undergo undamaged through all technological procedures together with turbine blades, including soldering and outgassing. DSC analyses indicates no additional thermal effects until melting, which confirms their structural stability. The examinations of microstructure revealed three types of constituents – TiC particles, matrix solid solution and blow outs – structural defects having negative effects on all the studied properties. It was found that heat resistance of nickel based sintered alloys at the temperature of 1100°C is superior as compared with the alloys based on cobalt and alloy ZhS32-VI. It has been established that wear resistance in conditions of fretting wear at temperatures of 20, 850, 950 and 1050°C of sintered alloy with ZhS32-VI matrix is mostly superior as compared with the other alloys. The properties of produced alloys allow to use them for manufacturing of components of friction couples operating in conditions of high temperature fretting wear, including protective pads of turbine blades top shrouds contact faces.
EN
A fast, simple, and economical method for extraction, preconcentration and determination of cobalt, nickel and copper as their 1-(2-pyridilazo) 2-naphthol (PAN) complexes based on ultrasound-assisted emulsification–microextraction (USAEME) and multivariate calibration of spectrophotometric data is presented. Various parameters affecting the extraction efficiency were optimized both with univariate and Box–Behnken design. The resolution of ternary mixtures of these metallic ions was accomplished by using partial least-squares regression (PLS), orthogonal signal correction-partial least-squares regression (OSC-PLS), and orthogonal signal correction-genetic algorithmspartial least-squares regression (OSC-GA-PLS). Under the optimum conditions, the calibration graphs were linear in the range of 2.0–150.0, 2.0–120.0 and 2.0–150.0 ng mL−1  for Co2+ , Ni2+ , and Cu2+ , respectively, with a limit of detection of 0.14 (Co2+ ), 0.13 (Ni2+ ) and 0.14 ng mL−1  (Cu2+ ) and the relative standard deviation was <2.5%. The method was successfully applied to the simultaneous determination of these cations in different samples.
EN
The paper presents the results of the studies of nickel-graphene composite coatings deposited by the electrochemical reduction method. A bath with low concentration of nickel ions, graphene as dispersed particles and organic compounds were used for deposition of the composite coatings nickel-graphene. The results of investigations of coatings deposited from the electrolyte containing 0.33, 0.5 and 1 g/dm3  graphene and two surface-active compounds were shown. The particles content in the coatings, the surface morphology, the cross-sectional structures of the coated samples, thickness and internal stresses were measured. Voltammetric method was used for examination of the corrosion resistance of samples of composite coatings in 0.5 M NaCl solution. The obtained results suggest that the content of incorporated graphene particles increases with an increasing amount of graphene in plating bath. The applications of organic addition agents was advantageous because it caused compressive stresses in the coatings. All of the nickel-graphene composite coatings had better corrosion resistance than the nickel coatings.
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