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Tytuł:
The Morphology of Eutectic Copper Oxides I (Cu2O) in The Processing of Wire Rod and Wires made from ETP Grade Copper
Autorzy:
Zasadzińska, M.
Knych, T.
Powiązania:
https://bibliotekanauki.pl/articles/355884.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Cu-ETP
Eutectic copper oxides Cu2O
evolution of Cu2O
fragmentation of oxides
Opis:
Eutectic copper oxides (Cu2 O) crystallize during the copper solidification process in the ETP grade copper which leads to high oxygen concentrations in interdendritic spaces. It has been experimentally found that they can be regular or elongated, and their size reaches several micrometres. During the multi-cage hot rolling process, homogenization of the oxide distribution in the entire volume of the wire rod occurs. This process is carried out in the soft copper matrix. Throughout the drawing process the fragmentation of oxides transpires along with changes in the shape from angular to more oval in a degree depending on the size of the deformation (wire diameter). Microcracks, fissures and local stress fields in the reinforced copper matrix arise around the oxide particles. The article presents the results of research on the evolution of copper oxides in ingots, wire rods and wires. The results of investigations of the wires properties and the limitations of the drawing process, especially of microwires, are presented.
Źródło:
Archives of Metallurgy and Materials; 2019, 64, 4; 1611-1616
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Laser-Assisted Copper Oxidation
Autorzy:
Musztyfaga-Staszuk, M.
Gawlińska-Nęcek, K.
Janicki, D.
Panek, P.
Powiązania:
https://bibliotekanauki.pl/articles/353054.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Cu
CuO
Cu2O
laser micro-processing
Opis:
The paper proposes a method for copper sheet oxidation by using a laser beam. The thickness of the oxide layer increases with temperature growth; therefore, the proper parameters of the experiment such as pulse power, frequency and the speed of the beam were adjusted. High power diode laser was used in the investigations. The topography of the oxidised copper sheets was determined using atomic force microscopy (AFM) and scanning electron microscopy with EDS analyses. Optical parameters of the deposited layer were characterised by spectrophotometry. Both roughness and thickness of the investigated samples were measured using the confocal laser scanning microscope. The technological recommendations for the laser micro-machining technology to obtain copper sheet oxidation by using the high power laser beam were selected.
Źródło:
Archives of Metallurgy and Materials; 2020, 65, 2; 767-770
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effects of copper ions on malachite sulfidization flotation
Autorzy:
Yin, Wanzhong
Sheng, Qiuyue
Ma, Yingqiang
Sun, Haoran
Yang, Bin
Tang, Yuan
Powiązania:
https://bibliotekanauki.pl/articles/110331.pdf
Data publikacji:
2020
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
malachite
sulfidization flotation
Cu2+ ion
depression
Opis:
In this study, the effects of copper ions (Cu2+) on the sulfidization (Na2S) flotation of malachite was investigated using micro-flotation experiments, zeta-potential measurements, X-ray photoelectron spectroscopy (XPS) analysis, adsorption experiments, and Materials Studio simulation. The results indicated that the flotation recovery of malachite decreased after the pretreatment of the mineral particles with Cu2+ ions prior to the addition of Na2S. The results for zeta-potential measurements and XPS analysis revealed that less sulfide ion species in the pulp solution transferred onto the mineral surface, the sulfidization of malachite surface weakened. The adsorption amount of collector on the mineral surface decreased, and this finding was confirmed by the results of the zeta-potential and adsorption experiments. Materials Studio simulation revealed that the adsorption energy of HS- ions and C4H9OCSS- ions on malachite surface increased after the adding of Cu2+ ion. The competitive adsorption made Cu2+ ions depress sulfidization flotation of malachite, the dissolution of mineral surface affected the adsorption of reagents on it, and decreased the floatability of malachite.
Źródło:
Physicochemical Problems of Mineral Processing; 2020, 56, 2; 300-312
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mold Temperature and Its Effect on Selected Properties of Cast AlSi5Cu2Mg Alloy
Autorzy:
Širanec, L.
Bolibruchová, D.
Chalupova, M.
Powiązania:
https://bibliotekanauki.pl/articles/2134208.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
mold
temperature
AlSi5Cu2Mg
cylinder head
Opis:
The European Commission's ambitious plan to reduce CO2 emissions has a significant impact on the global automotive industry. Recent development of new diesel and petrol engines with direct injection is aimed at improving fuel efficiency while maintaining (or enhancing) engine performance. This naturally also increases the demands on the properties of the most stressed engine components (e.g., cylinder heads, engine blocks, pistons), which leads to the development of new materials. Presented work analysed the effect of different mold temperatures (60; 120; 180 °C) on mechanical, physical properties and microstructure of AlSi5Cu2Mg aluminium alloy. This alloy is currently being used for the production of cylinder head castings. The results showed that the changing mold temperature had an effect on mechanical properties (ultimate tensile strength and Young modulus values). SEM with EDX analysis of intermetallic phases revealed there were no size and morphology changes of Cu, Mg and Fe intermetallic phases when the mold temperature changed. No significant effect of different mold temperature on physical properties (thermal and electrical conductivity) and fracture mechanism occurred during experiment. Optimal combination of mechanical and physical properties of AlSi5Cu2Mg alloy was achieved using a permanent mold with temperature ranging from 120 to 180 °C.
Źródło:
Archives of Foundry Engineering; 2022, 22, 2; 57--62
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Microstructure, Mechanical Properties and Corrosion Behavior of Zr-Containing AlSi5Cu2Mg Alloy
Autorzy:
Bolibruchová, Dana
Širanec, Lukáš
Kajánek, Daniel
Chalupová, Mária
Powiązania:
https://bibliotekanauki.pl/articles/28099514.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
mechanical properties
zirconium
microstructure
corrosion
AlSi5Cu2Mg
Opis:
The aim of this paper was to analyze the impact of varying zirconium addition on selected properties of AlSi5Cu2Mg alloy. The results of this research showed that zirconium addition in the range of 0.05 to 0.20 wt. % caused a decrease in ultimate tensile strength and yield strength of the experimental alloys after T7 heat treatment, probably due to the formation of primary Al3Zr intermetallic phases. These phases were observed as an individual plates or as a formation of two crossed plate-like phases. Potentiodynamic polarization tests in 3.5% NaCl solution revealed that addition of Zr had a positive effect on thermodynamic corrosion stability of the AlSi5Cu2Mg alloy due to shift of the corrosion potential to a more positive values for all as-cast samples. Addition of Zr in the as-cast alloys improved corrosion kinetics by lowering of corrosion current density.
Źródło:
Archives of Metallurgy and Materials; 2023, 68, 2; 749--756
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Cu2+/Zeolite catalyzed synthesis and evaluation of antimicrobial activities of some chalcones
Autorzy:
Thirunarayanan, G.
Kumar, N. Dinesh
Powiązania:
https://bibliotekanauki.pl/articles/1179609.pdf
Data publikacji:
2017
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Antimicrobial activities
Aryl chalcones
Cu2+/Zeolite
IR and NMR spectra
Opis:
Some aryl chalcones have been synthesized by Cu2+/Zeolite catalyzed aldol condensation of aryl methyl ketones and substituted benzaldehydes under microwave irradiation conditions. The yields of the synthesized chalcones are more than 85%. These chalcones were characterized by their physical constants and spectroscopic data. The antimicrobial activities of synthesized chalcones were studied by Bauer-Kirby disc diffusion method.
Źródło:
World Scientific News; 2017, 74; 251-266
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synthesis And Characterization Of SiO2, SnO2 And TiO2 Metal Oxide Shells Covering Cu2O Particles
Synteza i charakterystyka powłok tlenkowych SiO2, SnO2 i TiO2 pokrywających cząstki Cu2O
Autorzy:
Yu, R.
Yun, J.
Kim, Y.
Powiązania:
https://bibliotekanauki.pl/articles/355566.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Cu2O
metal oxide coating
pH value
SiO2
TiO2
SnO2
powłoki tlenkowe
Opis:
In this work is described a means of improving the chemical stability of Cu2O@SiO2, Cu2O@SnO2 and Cu2O@TiO2 materials. The SiO2, SnO2 and TiO2 coated samples were stable from pH 3 to pH 10 for up to seven days. To determine the stability of the coated nanoparticles, and their colloidal solutions under acidic and basic conditions, colloidal nanoparticle solutions with various pH values were prepared and monitored over time. Details of the effect of variations in pH on the phase stability of core-shell type Cu2O were characterized using transmission electron microscopy and X-ray diffraction.
Źródło:
Archives of Metallurgy and Materials; 2015, 60, 2B; 1159-1163
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wpływ modyfikacji zeolitów na ich właściwości fizykochemiczne
Impact of zeolites modification on their physicochemical properties
Autorzy:
Świderska-Dąbrowska, R.
Schmidt, R.
Powiązania:
https://bibliotekanauki.pl/articles/1819297.pdf
Data publikacji:
2012
Wydawca:
Politechnika Koszalińska. Wydawnictwo Uczelniane
Tematy:
ion exchange
natural clinoptilolite
removal
cations
metals
Cr3+
cu2+
pb2+
Fe3+
Opis:
Zeolites are crystalline, hydrated aluminosilicates of alkali and alkaline earth metals (Na, K, Mg, Ca, Sr, Ba), in which the pore size is 0.3-1.2 nm and depends on the structure of the zeolite. They consist of tetrahedrons of [AlO4]-5- and [SiO4]4-, which make ordered crystal lattice of rings, channels and chambers. Variable degree of oxidation of silicon (IV) and aluminum (III) causes their electronegative character. The size of the charge may determine the adsorption, ion exchange and catalytic capacities of zeolite. The structure made of ring tetrahedron units contains open tunnels, making zeolites also molecular sieves. Zeolites are mostly used for adsorption of ammonium ions from aqueous solutions, removal of radioactive elements and heavy metals, and recent studies suggest the possibility of application of zeolites for removal of chloroorganic compounds and oily pollutants. The most widely used zeolite in practice for water and wastewater treatment is clinoptilolite, which is characterized by large ion exchange and adsorption capacity. Authors of many works explain the adsorption process with ion exchange. But when interpreting the results the authors do not consider that the zeolites have also tunnels that make them also molecular sieves. As a result of ion adsorption on clinoptilolite in hydrogen or sodium form, pH of the solution decreases, resulting in possible formation of electropositive, electronegative complexes and dissociated ions which make up aquaions, increasing or decreasing the effectiveness of their removal. During usage of modified zeolites for the adsorption of ions from aqueous solutions, many accompanying processes take place, such as precipitation, coprecipitation and catalytic adsorption. The influence of the physicochemical properties of natural zeolite and zeolite in the hydrogen form on an aqueous solution in the process of washing out is presented in the paper. Presented results clear prove that the decisive factor affecting the quality of the aqueous solution after the washing out process is initial pH of the solution. Depending on method of modification, physicochemical properties of zeolites can vary considerably. Transformation of natural zeolite into the hydrogen form increases its acidity and physical and chemical resistance. Modification of zeolite with HCl may also increase the content of pure zeolite by dissolution of other, non-zeolite materials. Zeolite H has a greater content of of silicon and aluminum compounds in relation to total mass which is a result of introduction of protons into the zeolite. This is confirmed by lower content of alkali metals and alkaline earth metals (sodium, calcium and potassium) in ZH. Exchange of ions of sodium, potassium, calcium for protons is a result of modification of ZN with HCl. Examination of washing out process showed that there is a small migration of impurities (Fe and Ca) from ZH as compared to ZN. At the same time increase of iron content in the solution increases its turbidity. And also turbidity depends on the initial pH of the solution. It's highest value was observed when the initial pH was equal to 6. Significant increase of turbidity as a function of pH is mainly caused by abrasion of zeolite grains in the process of shaking and by formation of precipitable complexes of iron and calcium. The paper presents also the results of zeta potential measurements. potential of H zeolite in the investigated range of pH has a much higher absolute values compared to ZN and vary in the range from -20 mV to -30 mV. H zeolite has a higher electrostatic activity than natural zeolite. Potential creating ions such as H+ and OH- have decisive influence on the zeolite surface charge.
Źródło:
Rocznik Ochrona Środowiska; 2012, Tom 14; 460-470
1506-218X
Pojawia się w:
Rocznik Ochrona Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optical and Structural Properties of Cu2O thin Film as Active Layer in Solar Cells Prepared by DC Reactive Magnetron Sputtering
Autorzy:
Sawicka-Chudy, P.
Wisz, G.
Sibiński, M.
Cholewa, M.
Potera, P.
Głowa, Ł.
Pawełek, R.
Powiązania:
https://bibliotekanauki.pl/articles/352619.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Cu2O thin films
optical properties
surface properties
compositional properties
energy band gap
Opis:
A series of copper oxide thin films were synthesized through direct current magnetron sputtering on glass and silicon substrates with various process parameters. Initially, optical microscopy images and their histograms were analyzed to determine the optical quality of the obtained layers and then histograms were created using Image Histogram Generator software. Next, the morphology, and cross-section and layer composition of the samples were evaluated. Finally, the transmission spectra of the thin films were recorded. Transmittance and reflection spectra of the UV–vis analysis were utilized to calculate the optical band gap, the extinction coefficient, and the absorption coefficient of the oxidized layers. Samples showed low transmittance (up to 40%) in the region of 400 to 1000 nm. The mean absorption coefficient varied from ~3 · 105 to ~6 · 105 1/cm and from ~2 · 105 to ~4 · 105 1/cm in the region of 2 eV to 3.5 eV. The extinction coefficient ranged from 0 to 0.11 in the region from 300 to 3000 nm. Reflectance of the samples was ~20% in the region of 1000 to 2500 nm and ranged from 20%-50% in the region of 1000 to 3000 nm. We verified the process parameters of the Cu2O structure to improve the quality as a buffer layer. On the basis of this preliminary analysis, we propose the most promising and future-oriented solutions in photovoltaic applications.
Źródło:
Archives of Metallurgy and Materials; 2019, 64, 1; 243-250
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Acid mine drainage treatment by perlite nanomineral, batch and continuous systems
Oczyszczanie kwaśnych wód kopalnianych przy wykorzystaniu nanominerału perlitu – systemy działania ciągłego i okresowego
Autorzy:
Shabani, K. S.
Ardejani, F. D.
Badii, K.
Olya, M. E.
Powiązania:
https://bibliotekanauki.pl/articles/218773.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
nanocząsteczki perlitu
adsorpcja jonów Cu2+
adsorpcja jonów Fe2+  
adsorpcja jonów Mn2  
kopalnia miedzi i porfirów Sarcheshmeh
systemy działania ciągłego i okresowego
acid mine drainage
perlite nanoparticles
Cu2+, Fe2+ and Mn2+ ions adsorption
Sarcheshmeh porphyry copper mine
batch and continuous systems
Opis:
In this paper the adsorption activity of perlite nanoparticles for removal of Cu2+, Fe2+ and Mn2+ ions at Iran Sarcheshmeh copper acid mine drainage was discussed. Thus, raw perlite that provided from internal resource was modified and prepared via particles size reduction to nano scale and characterized by X-ray diffraction, X-ray fluorescence, scanning electron microscopy, transmission electron microscopy, Fourier transforms infrared and BET specific surface area analysis. The results of acid mine drainage show that pH of acid mine drainage is 5.1 and Cu2+, Fe2+ and Mn2+ ions are 10.5, 4.1 and 8.3 ppm, respectively. Firstly in the batch system the influence of adsorbent dose and temperature parameters were considered and then isothermal and kinetic models were investigated. According to the results the Langmuir isotherm and pseudo-second order kinetic model showed better correlation with the experimental data than other isotherm and kinetic models. Obtained thermodynamic parameters such as ΔG°, ΔH° and ΔS° show that the Cu2+, Fe2+ and Mn2+ ions adsorption from acid mine drainage is spontaneous and endothermic. Finally, perlite nanoparticles adsorbent was packed inside a glass column and used for the removal of heavy metals in 1, 3, 5 ml/min acid mine drainage flow rates, the breakthrough curves show that the column was saturated at 180, 240 and 315 min for different flow rates, respectively. According to the obtained results, this abundant, locally available and cheap silicate mineral showed a great efficiency for the removal of heavy metal pollutants from acid mine drainage and can be utilized for much volume of acid mine drainage or industrial scale.
W pracy omówiono zdolności adsorpcyjne nano-cząsteczek perlitu wykorzystywanych o usuwania jonów Cu2+, Fe2+ i Mn2+ z kwaśnych wód kopalniach w kopalni miedzi w Sarcheshmeh w Iranie. Surowy perlit pozyskiwany ze źródeł własnych został zmodyfikowany i odpowiednio spreparowany poprzez zre-dukowanie cząsteczek do rozmiarów rzędu nano- cząsteczek. Perlit poddany został następnie badaniom z wykorzystaniem dyfrakcji promieniowania rentgenowskiego, rentgenowskiej analizy fluorescencyjnej, skaningowej mikroskopii elektronowej, transmisyjnej mikroskopii elektronowej, spektroskopii w podczerwieni z transformatą Fouriera. Przeprowadzono także badania powierzchni właściwej w oparciu o równanie BET. Wyniki badań kwaśnych wód kopalnianych wykazują ich kwasowość na poziomie 5.1, a zawartość jonów Cu2+, Fe2+ i Mn2 wynosi odpowiednio 10.5, 4.1, 8.3 ppm. W pierwszym etapie analizowano system działania okresowego, zbadano wpływ następujących parametrów: ilości czynnika absorbującego i temperatury. Następnie przebadano modele izotermiczne i kinetyczne. Na podstawie uzyskanych wyników wykazano, że izoterma Langmuira oraz model pseudo-kinetycznego drugiego rzędu wykazują lepszą zgodność z danymi eksperymentalnymi niż pozostałe modele izotermiczne i kinetyczne. Uzyskane parametry termodynamiczne: ΔG°, ΔH° i ΔS° wskazują, że adsorpcja jonów Cu2+, Fe2+ i Mn2 z kwaśnych wód kopalnianych przebiega spontanicznie i jest procesem endotermicznym. W końcowym etapie badania nanocząsteczki perlitu- adsorbentu zostały umieszczone wewnątrz szklanej kolumny i wykorzystane do usuwania jonów metali ciężkich z kwaśnych wód kopalnianych podawanych z prędkością przepływu 1, 3, 5 ml/min. Krzywe przebicia wskazują, że kolumna została nasycona odpowiednio po 180, 240 i 315 dla odpowiednich prędkości przepływu. Uzyskane wyniki wskazują, że ten występujący lokalnie w dużych ilościach, tani i łatwo dostępny minerał krzemianowy wykazuje wysoką skuteczność w usuwaniu z kwaśnych wód kopalniach zanieczyszczeń w postaci metali ciężkich, dlatego też może być z powodzeniem wykorzystany do oczyszczania znacznych ilości wód a także na skalę przemysłową.
Źródło:
Archives of Mining Sciences; 2014, 59, 1; 107-122
0860-7001
Pojawia się w:
Archives of Mining Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Catalytic conversion of lignin by immobilized Cu[H4]salen and [H2]salen complexes under hydrothermal conditions
Autorzy:
Zhou, Xue-Fei
Powiązania:
https://bibliotekanauki.pl/articles/342450.pdf
Data publikacji:
2020
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Technologii Drewna
Tematy:
organosolv lignin
Cu([H4]salen)
Cu([H2]salen)
hydrothermal pyrolysis
Opis:
A comparative investigation was made of the effect of catalysis by immobilized Cu([H4]salen) on the hydrothermal conversion of organosolv lignin. The immobilization and hydrogenation of the complexes led to increased yield of liquid products compared with the corresponding unimmobilized and unhydrogenated complexes in catalytic conversion of lignin. In addition, the method of immobilization of the complexes affected the catalytic performance in lignin conversion, in which a higher yield of liquid products was obtained with the SB-immobilized complexes (ship-in-bottle method) than with the IM-immobilized complexes (impregnation method). The yield of liquid products obtained with Cu([H2]salen) at 250°C and 4 MPa O2 in water was 6.00%, compared with 16.80% and 22.08% respectively for Cu([H4]salen)/IM and Cu([H4]salen)/SB. Additionally, the addition of organic solvent had a marked effect on the catalytic performance of Cu([H4]salen), and the highest yield of liquid products (27.06%) was observed with Cu([H4]salen)/SB in water/methanol (80/20, v/v). The total yield of liquid products varied depending on temperature and oxygen pressure, and reached 46.01% under reaction conditions of 280°C and 6 MPa O2 in water/methanol (80/20, v/v). GC-MS analysis showed the main compounds in the liquid products to be phenols, with a yield of 32.16%. Other compounds included alcohols, ketones, aromatics, olefins, cycloalkanes, and alkanes. A mechanism for their formation was proposed based on the oxidation of a lignin model compound under hydrothermal conditions.
Źródło:
Drewno. Prace Naukowe. Doniesienia. Komunikaty; 2020, 62, 205; 81-91
1644-3985
Pojawia się w:
Drewno. Prace Naukowe. Doniesienia. Komunikaty
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
EPR spectroscopy of Cu2+ and Mn2+ in borate glasses
Autorzy:
Drzewiecki, A.
Padlyak, B.
Adamiv, V.
Burak, Y.
Teslyuk, I.
Powiązania:
https://bibliotekanauki.pl/articles/147654.pdf
Data publikacji:
2013
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
borate glasses
Cu2+ paramagnetic centre
electron paramagnetic resonance (EPR) spectroscopy
hyperfine structure
Mn2+ paramagnetic centre
Opis:
Electron paramagnetic resonance (EPR) spectra of the CaB4O7 and LiCaBO3 glasses containing 0.5 and 1.0 mol.% CuO and MnO2 impurity compounds were investigated at room temperature. The glasses with CaB4O7:Cu, LiCaBO3:Cu, CaB4O7:Mn and LiCaBO3:Mn compositions were produced from the corresponding polycrystalline compounds using standard glass synthesis and technological conditions developed by the authors. The EPR spectral parameters of the Cu2+ and Mn2+ centres in both glasses containing 0.5 and 1.0 mol.% CuO and MnO2 doping oxides were determined. Analysis of EPR spectral parameters shows that Cu impurity is incorporated into the CaB4O7 and LiCaBO3 glass network as isolated Cu2+ (3d9, 2D5/2) paramagnetic ions. The Cu2+ ions occupy Ca(Li) sites of the borate glass network coordinated by six O2− anions with geometry of elongated octahedron (D4h symmetry) due to the Jahn- -Teller effect. The EPR spectra of the Mn-doped CaB4O7 and LiCaBO3 glasses are virtually identical and typical of all oxide glasses activated with Mn2+ (3d5, 6S5/2) ions. Observed EPR spectra in the Mn-doped glasses were attributed to isolated Mn2+ (1) centres (geff ≅ 4.3) in octahedral Ca(Li) sites with a strong (fully) rhombic distortion, isolated Mn2+ (2) centres (geff ≅ 2.0) in octahedral Ca(Li) sites with nearly cubic local symmetry as well as pairs and small clusters of the Mn2+ ions, coupled by magnetic dipolar and exchange interactions. On the basis of the obtained results and analysis of referenced data, the local structure of the Cu2+ and Mn2+ centres in the borate glasses have been proposed.
Źródło:
Nukleonika; 2013, 58, 3; 379-385
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Flexible-elastic deformation measurement of ZnS:Cu2+ mechanoluminescent film using visual inspection and digital image correlation
Autorzy:
Gu, Guo-Qing
Xu, Gui-Zhong
Shen, Feng
Zhou, Peng
Sun, Hou-Chao
Weng, Jia-Xing
Powiązania:
https://bibliotekanauki.pl/articles/27311740.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
ZnS:Cu2+-PDMS mechanoluminescent film
flexible-elastic deformation performance
visual inspection
digital image correlation
Opis:
ZnS-based mechanoluminescent film has been widely used in the fields of stress visualization and stress sensing, due to its high brightness and repeatable stable luminescent characteristics. To evaluate the flexible-elastic deformation performance of ZnS-based mechanoluminescent film, both visual inspection and digital image correlation (DIC) are, respectively, employed for measuring the ZnS-based mechanoluminescent film. ZnS:Cu2+ mechanoluminescent powders are first mixed with polydimethylsiloxane (PDMS) matrix to produce ZnS:Cu2+-PDMS mechanoluminescent film. Then, two measurement experiments are, respectively, conducted to investigate the mechanical response and the flexible-elastic deformation performance of the prepared ZnS:Cu2+-PDMS mechanoluminescent film. On one hand, the mechanical response performance of the ZnS:Cu2+-PDMS mechanoluminescent film is validated by visual monitoring of composite concrete fracture processes. On the other hand, the prepared ZnS:Cu2+-PDMS mechanoluminescent film is also measured by DIC to obtain its full-field deformations and strains information. The flexible-elastic deformation performance of the ZnS:Cu2+-PDMS mechanoluminescent film is well demonstrated by the DIC measured results.
Źródło:
Metrology and Measurement Systems; 2023, 30, 2; 353--365
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Antiviral Activities of Cu2+ Ions in Viral Prevention, Replication, RNA Degradation, and for Antiviral Efficacies of Lytic Virus, ROS-Mediated Virus, Copper Chelation
Autorzy:
Ishida, Tsuneo
Powiązania:
https://bibliotekanauki.pl/articles/1177808.pdf
Data publikacji:
2018
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Capsid protein
Copper chelation
Copper homeostasis
Copper oxide nanoparticles
Cu2+ and Cu1+ ions
DNA/RNA virus
HSV
ROS
Viral replication
mRNA degradation or decay
Opis:
Copper has been known for decades that marked changes of micronutrient homeostasis in the host are accompanied by infection or inflammation. Copper levels in the serum are significantly elevated in response to inflammation that copper accumulates at sites of inflammation. Easily oxidized copper oxide nanoparticles (CuONPs) are widely used as catalysts that the ability of CuONPs to reduce bacterial population and virus application is enhanced. The mechanism of copper-mediated inactivation of herpes simplex virus (HSV) is by which cupric ions oxidatively damage biomolecules. Virus-mediated subjugation and modulation of host lipids during infection that the life cycle of most viruses proceeds through a series of basic steps: binding and internalization, fusion, uncoating, of the viral genome, its replication, assembly of new particles, and budding or release of the newly made viruses. The HIV-1 protein Vpu is an 81-amino-acid (16-kDa) type I which the presence of Vpu leads to the degradation of BST-2 via an endosome-lysosome degradation pathway. Oxidative degradation by a Cu-metalloenzyme, and ubiquitin-mediated degradation of cellular proteins were exploited. Copper can disrupt the lytic cycle of the Coccolithovirus. Lysins represent a novel class of anti-infectives derived from bacteriophage which lysins are bacterial cell wall hydrolytic enzymes that selectively and rapidly kill specific bacteria. Regarding copper induced cellular toxicity, several mechanisms have been proposed based on the formations of ROS by free Cu ions as cupric and cuprous ions can participate in redox reactions. ROS (O2ˉ,・OH, OHˉ), Cu+ and H2O2 play the important roles for viral inactivations. Thujaplicin-copper chelates inhibit influenza virus-induced apoptosis. Pyrrolidine dithiocarbamate as a metal ion binding agent inhibits the activity of the viral proteases of polyprotein processing and RNA replication of HRV. Chelation enables metals are capable of ligand scavenging via complexation, since reverse transcriptase enzyme inhibits the growth and replication of RNA tumor viruses. Thus, copper complex and copper chelation enhance antiviral efficacy.
Źródło:
World Scientific News; 2018, 99; 148-168
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Microstructural Morphology on Microscale Deformation Behavior of Al-4.5Cu-2Mg Alloy
Autorzy:
Biswas, P.
Bhandari, R.
Mondal, M. K.
Mandal, D.
Powiązania:
https://bibliotekanauki.pl/articles/351178.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Al-4.5Cu-2Mg alloys
optical microstructure
representative volume element
RVE
finite element method
microscale deformation
Opis:
The microscale deformation behaviour of the Al-4.5Cu-2Mg alloy has been studied to understand the influence of various processing routes and conditions, i.e. the gravity casting with and without grain refiner, the rheocast process and the strain induced melt activation (SIMA) process. The micromechanics based simulations have been carried out on the optical microstructures of the alloy by 2D representative volume elements (RVEs) employing two different boundary conditions. Microstructural morphology, such as the grain size, the shape and the volume fraction of α-Al and binary eutectic phases have a significant effect on the stress and strain distribution and the plastic strain localization of the alloy. It is found that the stress and strain distribution became more uniform with increasing the globularity of the α-Al grain and the α-Al phase volume fraction. The simulated RVEs also reveals that the eutectic phase carries more load, but least ductility with respect to the α-Al phase. The SIMA processed alloy contains more uniform stress distribution with less stress localization which ensures better mechanical property than the gravity cast, grain refined and rheocast alloy.
Źródło:
Archives of Metallurgy and Materials; 2018, 63, 4; 1575-1586
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł

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