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1

Katalityczne zgazowanie stężonych ścieków zaolejonych w warunkach nadkrytycznych

Gao Ming, Xu Junjie, Chu Zhuzhuan, Li Hui, Su Hao

Przemysł Chemiczny

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2023

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T. 102, nr 10

1008--1012

PL

Do oczyszczania ścieków zawierających olej (zawartość 4000 mg/L) zastosowano katalityczne zgazowanie w warunkach nadkrytycznych. Katalizator nano-CuO został przygotowany i użyty (2 mg/L) w obecności H₂O₂ (do 300 mg/L). Katalizator wykazał wysoką aktywność w degradacji olejów zawartych w ściekach. Przy pH 11 i w temp 445°C wartość ChZT ścieków zmniejszyła się o 95,6% po 25 min oczyszczania.

EN

The catalytic supercrit. gasification was used to purify the oil-containing wastewater (oil content 4000 mg/L). The nano-CuO catalyst was prepd. and used (2 mg/L) in presence of H₂O₂ (up to 300 mg/L). The catalyst showed high activity in degrdn. of the wastewater-contained oils. At pH 11 and temp. 445°C, the COD of the wastewater decreased by 95.6% after 25 min long treatment.

2

Pb-doped cuo thin films synthetized by sol-gel method

Tabli Dalila, Touka Nassim, Baddari Kamel, Selmi Nourddine

Advances in Materials Science

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2022

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Vol. 22, nr 3(73)

5--13

EN

The physical properties of pure CuO and Pb doped CuO thin films, deposited on glass substrates by a sol-gel method, were investigated. Structural analysis revealed the polycrystalline nature of the pure CuO and Pb:CuO composite films with a monoclinic structure, the crystallite size decreased and ranged from 36.78 nm to around 21.5 nm. The SEM images of the CuO thin films showed that the Pb doping concentration affects the surface morphology of the Pb:CuO composites. The absorbance of the Pb:CuO composites is higher than that of the undoped CuO thin films. The optical band gap energies of undoped CuO and Pb doped CuO thin films were estimated to 1.9 (pure), 2.17(5%) and 2.74 (7%)eV, and found that the band gap energy (Eg) increases with the Pb concentration. This blue shift is due to the quantum confinement induced by the reduction in the size of the crystallites.

3

In situ thermal decomposition route: Preparation and characterization of nano nickel, cobalt, and copper oxides using an aromatic amine complexes as a low-cost simple precursor

Refat Moamen S., Mohamed Soha F., Altalhi Tariq A., Bakare Safyah B., Al-Hazmi Ghaferah H.

Polish Journal of Chemical Technology

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2021

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Vol. 23, nr 2

47--53

EN

The main interest now is the development of metallic or inorganic-organic compounds to prepare nanoparticle materials. The use of new compounds could be beneficial and open a new method for preparing nanomaterials to control the size, shape, and size of the nanocrystals. In this article, the thermal decomposition of [M2(o-tol)2(H2O)8]Cl4 (where o-tol is ortho-tolidine compound, M = Ni2+, Co2+, Cu2+) new precursor complex was discussed in solid-state conditions. The thermal decomposition route showed that the synthesized three complexes were easily decomposed into NiO, Co3O4 and CuO nanoparticles. This decomposition was performed at low temperatures (~600°C) in atmospheric air without using any expensive and toxic solvent or complicated equipment. The obtained product was identified by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM) and energy-dispersive X-ray spectroscopy (EDX). FT-IR, XRD and EDX analyses revealed that the NiO nanoparticles exhibit a face-centered-cubic lattice structure with a crystallite size of 9–12 nm. The formation of a highly pure spinel-type Co3O4 phase with cubic structure showed that the Co3O4 nanoparticles have a sphere-like morphology with an average size of 8–10 nm. The XRD patterns of the CuO confirmed that the monoclinic phase with the average diameter of the spherical nanoparticles was approximately 9–15 nm.

4

Thermal gravimetric analysis of glass fiber reinforced composite for understanding the impact of copper oxide in relation to titanium oxide filler particles

Alam Shahinoor, Chowdhury Mohammad Asaduzzaman

Composites Theory and Practice

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2021

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R. 21, nr 1-2

12--21

EN

In this work, the composite samples required to investigate their thermal properties were fabricated employing the conventional hand lay-up technique, followed by a light compression molding process. A fixed weight of plain woven glass fiber and epoxy with four different types of fillers as calcium carbonate (CaCO3), aluminum oxide (Al2O3), magnesium oxide (MgO) and titanium oxide (TiO2) or copper oxide (CuO) of different weights (5, 10 and 15 g) were studied. According to thermal gravimetric analysis (TGA), it was observed that the melting point (Tm) and glass-transition temperature (Tg) are affected by the presence of CuO and TiO2, which indicate the degree of composite crystallinity established by the stronger interfacial interaction by the CuO than that of the TiO2 particles and the amorphous region of the chain. These studies were supported by examination of the surface morphology of the composites by means of scanning electron microscopy (SEM).

5

Comparison of electrical properties of CuO/n-Si contacts with Cu/n-Si

Özmenteş Reşit, Temirci Cabir

Materials Science Poland

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2020

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Vol. 38, No. 3

475--483

EN

In this study, CuO/n-Si/Al heterojunction contacts were fabricated by thermal evaporation technique. Electrical characteristics of the samples were investigated with the current-voltage (I-V), capacitance-voltage/frequency (C-V/f), and conductance-voltage (G/V) measurements at room temperature. Also, Cu/n-Si/Al Schottky contact was produced as a reference sample to investigate the electrical properties of the samples. The values of ideality factor (n), barrier height (φb) and series resistance (Rs) of the samples were calculated from the forward bias current-voltage (I-V) and reverse bias capacitance-voltage (C-V) characteristics. Also, for checking the consistency of the results, Cheung and Norde functions were used. The experimental result values of CuO/n-Si contact were compared with the values of the reference Cu/n-Si Schottky diode. It was observed that the values of the ideality factor and barrier height of the CuO/n-Si heterojunction were higher than those of the Cu/n-Si Schottky contact, while the series resistance was lower. Also, it has been observed that the value of capacitance decreased with increasing frequency and after a certain value of frequency it was almost constant. The ideality factor of CuO/n-Si/Al heterostructure is about 2.40 and so, it is not close to the ideal behavior.

6

Laser-Assisted Copper Oxidation

Musztyfaga-Staszuk M., Gawlińska-Nęcek K., Janicki D., Panek P.

Archives of Metallurgy and Materials

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2020

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Vol. 65, iss. 2

767--770

EN

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.

7

Heterozłącza p-CuO/n-Si dla zastosowań fotowoltaicznych

Czerwosz Elżbieta, Biernacki Krzysztof, Wronka Halina, Kozłowski Mirosław, Diduszko Ryszard, Firek Piotr, Fetliński Bartosz

Elektronika : konstrukcje, technologie, zastosowania

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2019

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Vol. 60, nr 12

36--39

PL

W artykule został przedstawiony stan wiedzy na temat heterozłączy p-CuO/n-Si oraz ich zastosowań w fotowoltaice. Na tym tle zostały zaprezentowane wyniki naszych badań w dziedzinie technologii otrzymywania takich struktur, badań ich właściwości fizycznych metodami rentgenowskimi i elektronomikroskopowymi oraz badań ich właściwości fotowoltaicznych. Heterozłącza p-CuO/n-Si zostały otrzymane dzięki zastosowaniu nowej metody, opracowanej w naszym Instytucie (Łukasiewicz - ITR), polegającej na połączeniu metody PVD i metody utleniania termicznego. Szczegóły metody opisane są w artykule. Wyniki pomiarów fotoprądów pokazały, że opracowane struktury są odpowiednie do zastosowań fotowoltaicznych.

EN

The state-of-art in a field of p-CuO/n-Si heterojunctions and their application in photovoltaics is presented in this paper. On this background the results of our studies concerning technology of such structures preparation, their properties investigated with x-ray diffraction and electron-microscopy methods as well as their photovoltaic properties are shown. The p-CuO/n-Si heterojunctions were prepared by innovative method elaborated in our Institute (Łukasiewicz - ITR). This method connects PVD and thermal oxidation methods. Details of this method are described in the paper. The results of photovoltaic measurements exhibited that prepared p-CuO/n-Si heterojunctions are suitable for photovoltaic applications.

8

Facile synthesis of chitosan/CuO nanocomposites for potential use as biocontrol agents

Siriphannon P., Iamphaojeen Y.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2018

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Vol. 66, nr 3

311--316

EN

Chitosan/CuO nanocomposites (Chi/CuO) were prepared by facile and eco-friendly technique. The 2%w/v chitosan solution was mixed with 0.5 %w/w sodium tripolyphosphate (STPP), resulting in the formation of ionically crosslinked chitosan. The crosslinked chitosan was soaked in an aqueous solution containing 0.001, 0.01 or 0.1 mol/L CuSO4·5H2O for 24 hrs, in which the Cu2+ ions were absorbed into the chitosan network, forming as the chitosan/Cu2+ precursors. The chitosan/Cu2+ precursors were hydrothermally reacted in two different basic media, i.e. NaOH and NH4OH, at 100°C for 24 hrs, resulting in the nano-sized CuO crystals hydrothermally grew and embedded in the crosslinked chitosan matrix. The CuO grown in the NaOH possessed larger crystallite size and higher crystallinity than that in the NH4OH. In addition, the CuO crystallite size in the nanocomposites increased with the increase of initial concentration of Cu2+ starting agent due to the increase of Cu2+ quantity in the chitosan/Cu2+ precursors. The chitosan/CuO nanocomposites prepared by using 0.01 and 0.1 mol/L Cu2+ could exhibit the antibacterial activities after intimate contact with Staphylococcus aureus and Escherichia coli under JIS L 1902:1998 (Qualitative) test method, indicating their potential use as biocontrol agents.

9

Liquid petroleum gas sensing performance enhanced by CuO modification of nanocrystalline ZnO-TiO2

Pedhekar R. B., Raghuwanshi F. C., Kapse V. D.

Materials Science Poland

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2016

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Vol. 34, No. 3

571--581

EN

Nanocrystalline ZnO-TiO2 (with molar ratios 9:1, 7:3, 1:1, 3:7 and 1:9) were successfully synthesized by hydrothermal method. Synthesized materials were examined with the help of X-ray diffraction and transmission electron microscope. Liquid petroleum gas sensing characteristics of the ZnO-TiO2 films were investigated at different operating temperatures. The ZnO-TiO2 thick film (with 1:1 molar ratio) exhibited good response toward liquid petroleum gas as compared to other investigated compositions. Further, liquid petroleum gas sensing characteristics of CuO modified ZnO-TiO2 thick films were investigated. 0.2 M CuO modified ZnO-TiO2 thick film exhibited excellent liquid petroleum gas sensing characteristics such as higher response (~ 1637.49 at 185 °C) with quick response time (~30 s), low recovery time (~70 s), excellent repeatability and stability at low operating temperature.

10

New method of obtaining CuO-SnO2 nanocomposite

Martyła A., Kopczyk M., Osińska-Broniarz M., Marciniak P., Czapik A., Majchrzycki Ł., Przekop R.

Composites Theory and Practice

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2015

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R. 15, nr 4

214--217

EN

In this paper, we proposed a new synthesis method of a CuO-SnO2 composite based on the sol-gel technique and tin(IV) acetate as the precursor. In addition, for the first time we used a combination of high-energy homogenization and spray drying. The aim of the study was to obtain a nano-composite with a high Cu content. The system properties were investigated using XRD, TGA, TEM and SEM-EDS techniques. The obtained composite material contains an amorphous gel of tin(IV) hydroxide and crystalline copper(II) acetate. The presented method of synthesis allows for obtaining nano-composite particle sizes less than 50 nm, and a CuO-SnO2 nano-composite fraction with a particle size less than 5 nm. The small size of particles should result in high activity of the system.

PL

W niniejszej pracy proponujemy nową metodę otrzymywania układu CuO-SnO2, wykorzystującą technikę zol-żel i octan cyny(IV) jako prekursor SnO2. Ponadto, po raz pierwszy zastosowano połączenie techniki wysokoenergetycznej homogenizacji i suszenia rozpyłowego. Celem pracy było otrzymanie układu nanokompozytowego o wysokiej zawartości Cu. Otrzymane układy zostały poddane charakterystyce za pomocą technik XRD, TGA, TEM oraz SEM-EDS. Kompozyty zawierają amorficzny żel wodorotlenku cyny(IV) oraz krystaliczny octan cyny(II). Dzięki zastosowaniu wspomnianych technik udało się otrzymać cząsteczki o rozmiarach poniżej 50 nm, jak również pewną frakcję nanokompozytu CuO-SnO2 o rozmiarach poniżej 5 nm. Małe rozmiary cząstek powinny wpływać na wysoką aktywność takiego układu.

11

CuO as sintering additive to Sr0.4Ca0.6La4Ti5O17 ceramics

Manan A., Shah L. A., Attaullah

Materials Science Poland

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2013

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Vol. 31, No. 1

122-125

EN

The effects of CuO addition on the sintering behavior and microwave dielectric properties of Sr0:4Ca0:6La4Ti5O17 ceramics were investigated. CuO was selected as a liquid phase sintering aid to lower the sintering temperature of Sr0:4Ca0:6La4Ti5O17 ceramics. With CuO addition, the sintering temperature of Sr0:4Ca0:6La4Ti5O17 ceramics was effectively reduced from 1550 °C to 1475 °C. The crystalline phase exhibited no phase difference and no second phase was detected at all addition levels. The electric permittivity was not significantly affected by various amounts of CuO addition and ranged from 52 to 54. Small values (<+7 ppm/K) of the temperature coeficient of resonant frequency were obtained for Sr0:4Ca0:6La4Ti5O17 ceramics. However, the unloaded quality factor Qu was strongly dependent upon the CuO concentration. Qu fo - 10500 GHz was obtained for Sr0:4Ca0:6La4Ti5O17 ceramics with 0.5 wt.% of CuO addition, sintered at 1475 °C.

12

Bulk ZnO nanorod assemblies fabricated by spin coating of organo-precursor gels on CuO nanowires

Uma K., Anathakumar S., Mangalaraja R. V., Soga T., Jimbo T.

Materials Science Poland

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2013

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Vol. 31, No. 3

397--403

EN

Bulk ZnO nanorod assemblies have been successfully fabricated on CuO nanowires through spin coating of organoprecursor gels. A thin film of CuO nanowires was first generated by direct heating of a metallic Cu-foil at 500 A degrees C in an air atmosphere. A stable colloidal organo-precursor sol synthesized by dissolving equimolar zinc acetate dihydrate and monoethanolamine in 2-methoxyethanol was subsequently repeatedly deposited onto the CuO nanowires by spin coating. The formation of ZnO nanorod assemblies was controlled by varying the number of coatings. The average diameter of the ZnO rods was determined to be similar to 600 nm.

13

Dielectric properties of composites in the CaO-CuO-TiO2 system

Ren S., Wittmar M., Aslan M., Grobelsek I., Quilitz M., Veith M.

Materiały Ceramiczne

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2010

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T. 62, nr 4

449-455

EN

Since ultra-high dielectric constants (> 104) with weak temperature and frequency dependence were observed in non-ferroelectric materials such as CaCu3Ti4O12 and CuO, it is very meaningful to study the dielectric properties not only of CaCu3Ti4O12 and CuO, but also of other members in the CaO-CuO-TiO2 system in order to find other compositions with similar characteristics, to discover the underlying mechanisms and to search for new composites with even better dielectric properties. The dielectric properties of the composites in ternary systems CuO-CaCu3Ti4O12-CaTiO3 and CaCu3Ti4O12-CaTiO3-TiO2 have been tentatively investigated in the present study. The frequency and temperature dependences of permittivity and impedance in the range of 102-5 x 106 Hz and 25-130°C were investigated in the representative high permittivity (> 104) composite with molar fraction of Cu/Ti/Ca of 85/10/5 in the ternary CuO-CaCu3Ti4O12-CaTiO3 system. Strong hints suggest an important effect of grain boundary contributions on dielectric properties. Preliminary results demonstrated that a multiphase microstructure consisting of larger grains with predominant phase surrounded by smaller grains with secondary phases played an important role for enhancing the dielectric response due to possible barrier layer effects caused by the grain boundary of the composites.

PL

Od kiedy zaobserwowano ultra wysokie stałe dielektryczne (> 104), przy słabej zależności od temperatury i częstotliwości, w nieferroelektrycznych materiałach takich jak CaCu3Ti4O12 i CuO, zasadnym stało się badanie właściwości dielektrycznych nie tylko CaCu3Ti4O12 i CuO, ale także innych członków układu CaO-CuO-TiO2 po to, aby znaleźć inne składy o podobnej charakterystyce, aby odkryć podstawowe mechanizmy, i aby poszukiwać nowe kompozyty o nawet lepszych właściwościach dielektrycznych. W prezentowanej pracy zbadano wstępnie właściwości dielektryczne kompozytów w układach potrójnych CuO-CaCu3Ti4O12-CaTiO3 i CaCu3Ti4O12-CaTiO3-TiO2. Częstotliwościowe i temperaturowe zależności przenikalności dielektrycznej i impedancji w zakresie 102-5 x 106 Hz and 25-130°C zbadano w przypadku reprezentatywnego kompozytu o wysokiej przenikalności (> 104) o udziale molowym Cu/Ti/Ca wynoszącym 85/10/5 w układzie trójskładnikowym CuO-CaCu3Ti4O12-CaTiO3. Mocne przesłanki sugerują ważny wpływ przyczynków związanych z granicami międzyziarnowymi na właściwości dielektryczne. Wstępne wyniki pokazały, że wielofazowa mikrostrukura składająca się z większych ziaren dominującej fazy otoczonych przez mniejsze ziarna fazy drugorzędnej odgrywała ważną rolę w przypadku podniesienia odpowiedzi dielektrycznej, w związku z możliwymi efektami warstwy barierowej wywołanymi przez granicę międzyziarnową kompozytów.

14

Model struktury defektów w tlenku CuO

Migdalska M., Grzesik Z.

Ochrona przed Korozją

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2009

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nr 11

529-531

PL

W oparciu o wyniki wcześniejszych badań mechanizmu powstawania fazy CuO na powierzchni Cu2O, uzyskane metodami markerów i dwuetapowego utleniania oraz kinetyki utleniania Cu2O w funkcji temperatury i prężności tlenu, wykazano, że dominującymi defektami punktowymi w tlenku CuO są podwójnie zjonizowane wakacje kationowe. Przedstawiony w niniejszej pracy model struktury defektów uwzględnia fakt, że w zgodności z wynikami badań eksperymentalnych, stężenie defektów jonowych w omawianym tlenku, będącym samoistnym półprzewodnikiem elektronowym, rośnie z prężnością tlenu w potędze 1/2.

EN

Basing on experimental results reported previously and obtained using marker and two-stage oxidation methods as well as oxidation kinetic rates measurements, the defect structure model of CuO has been presented. It has been demonstrated that the predominant point defects in the discussed oxide, being an intrinsic electronic semiconductor are doubly ionized cation vacancies, the concentration of which increases with oxygen activity with power 1/2.