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1

Wpływ węglanów litu, strontu i baru na fazę belitu tworzoną przy temperaturze 1200°C

Ghorab Hanaa Youssef, Abbas Mostafa, Arafa Ahmed, Hassan Hassan Eid

Cement Wapno Beton

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2023

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R. 28, nr 6

428--437

PL

Worcowy belit został przygotowany poprzez wypalenie kalcytu i kwarcu w stosunku molowym 2 przez 1,5 godziny w temperaturze 1200°C. Zidentyfikowano odmiany polimorficzne belitu utworzone przy dodatku Li2CO3 z 1% Li2O jako topnika i domieszki oraz SrCO3 i BaCO3 w ilościach równoważnych 8% SrO i 8% BaO jako mineralizatorów. Utworzone odmiany polimorficzne zbadano za pomocą dyfraktometrii rentgenowskiej z analizą Rietvelda oraz zbadano pod skaningowym mikroskopem elektronowym. Stwierdzono, że odmiany β i γ równie często powstają w belicie z domieszką strontu, a w obecności baru pojawia się również α’. Rozkład Li2CO3 do Li2O jest opóźniony przez węglany strontu i baru z powodu wzrostu ciśnienia parcjalnego CO2 i w konsekwencji stopiony materiał jest stabilizowany. Konieczne są dalsze badania w celu wyjaśnienia wpływu ciśnienia parcjalnego CO2 węglanów na polimorfizm krzemianu dwuwapniowego.

EN

A reference belite is prepared from burning calcite and quartz at mole ratio = 2, for 1.5 hours at 1200°C. Belite polymorphs formed in the presence of Li2CO3 with 1% Li2O, as a fluxing and doping agent, in addition to SrCO3 and BaCO3 with amounts equivalent to 8% SrO and 8% BaO, as mineralizers, were identified. The thermal behavior of the belite mixes and of the pure carbonates was recorded for temperatures up to 1300°C. The polymorphs formed are defined by means of X-ray Rietveld analysis, and examined under a scanning electron microscope. It is found that the β and γ polymorphs are equally formed in the belite doped with strontium, and in the presence of barium, the α’ appears as well. The decomposition of Li2CO3 to Li2O is depressed by strontium and barium carbonates due to the increase in the partial pressure of CO2 and consequently the melt is stabilized. Further research is needed to explain the effect of CO2 partial pressure of the carbonates on the polymorphism of belite.

2

Fabrication and characterization of Zn doped CuO nanofiber using newly designed nanofiber generator for the photodegradation of methylene blue from textile effluent

Sethuraman R. G., Venkatachalam T., Kirupha S. D.

Materials Science Poland

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2018

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Vol. 36, No. 3

520--529

EN

High aspect ratio, Zn doped copper oxide (Zn-CuO) nanofibers have been fabricated employing a newly designed electrospun coating unit using copper acetate, sodium hydroxide and polyethylene glycol in aqueous state. The prepared Zn doped copper oxide (Zn-CuO) nanofibers were sintered at 400 °C, 500 °C and 600 °C separately and characterized using X-ray diffraction XRD, Fourier transformation infrared spectroscopy FT-IR, scanning electron microscopy SEM, energy dispersive spectroscopy EDS. The average crystallite size was in the range of 28 nm to 30 nm. Optical properties of Zn-CuO nanofibers were analyzed using UV-DRS studies which showed a blue shift in the absorption band. An increase in band gap with the increase in postannealing temperature was observed due to the blue shift in absorption edge of CuO causing enhanced photodegradation. The catalytic properties of the CuO nanofibers were tested using methylene blue in aqueous medium. The influences of parameters responsible for high photodegradation were optimized and the rate of the photodegradation process was calculated using photodegradation kinetics. The reusability test was conducted to find the stability of the fabricated Zn-CuO nanofibers.

3

Dopant-Based Charge Sensing Utilizing P-I-N Nanojunction

Nowak R., Jabłoński R.

Metrology and Measurement Systems

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2017

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Vol. 24, nr 2

391--399

EN

We studied lateral silicon p-i-n junctions, doped with phosphorus and boron, regarding charge sensing feasibility. In order to examine the detection capabilities and underlying mechanism, we used in a complementary way two measurement techniques. First, we employed a semiconductor parameter analyzer to measure I−V characteristics at a low temperature, for reverse and forward bias conditions. In both regimes, we systematically detected Random Telegraph Signal. Secondly, using a Low Temperature Kelvin Probe Force Microscope, we measured surface electronic potentials. Both p-i-n junction interfaces, p-i and i-n, were observed as regions of a dynamic behaviour, with characteristic time-dependent electronic potential fluctuations. Those fluctuations are due to single charge capture/emission events. We found analytically that the obtained data could be explained by a model of two-dimensional p-n junction and phosphorus-boron interaction at the edge of depletion region. The results of complementary measurements and analysis presented in this research, supported also by the previous reports, provide fundamental insight into the charge sensing mechanism utilizing emergence of individual dopants.

4

Morphologies of nanostructured bismuth sulphide and Mn (II) doped bismuth sulphide nanoparticles: characterization and application

Anasane N., Ameta R.

Materials Science Poland

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2017

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Vol. 35, No. 1

6--13

EN

Different morphologies of bismuth sulphide (Bi2S3) nanoparticles (NPs) were synthesized at room temperature using wet chemical method. The properties of bismuth sulphide (Bi2S3) nanoparticles can be controlled by different amounts of Mn2+ dopant. The synthesized nanoparticles were characterized by several techniques, such as high resolution scanning electron microscopy (HR-SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM), electron diffraction (ED), and energy dispersive X-ray spectroscopy (EDS). The nanoparticles (Bi2S3) were found to have excellent activity for the UV light assisted decolorization of methyl violet dye and also helped to speed up the redox reaction of Fe(CN)3−6 and S2O2−3. The reactions were monitored through UV-Vis spectroscopy.

5

Fabrication and characterization of nanostructured Ba-doped BiFeO3 porous ceramics

Mostafavi E., Ataie A.

Materials Science Poland

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2016

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Vol. 34, No. 1

148--156

EN

Nanostructured barium doped bismuth ferrite, Bi0.8Ba0.2FeO3 porous ceramics with a relatively high magnetic coercivity was fabricated via sacrificial pore former method. X-ray diffraction results showed that 20 wt.% Ba doping induces a structural phase transition from rhombohedral to distorted pseudo-cubic structure in the final por(o)us samples. Moreover, utilizing Bi0.8Ba0.2FeO3 as the starting powder reduces the destructive interactions between the matrix phase and pore former, leading to an increase in stability of bismuth ferrite phase in the final porous ceramics. Urea-derived Bi0.8Ba0.2FeO3 porous ceramic exhibits density of 4.74 g/cm3 and porosity of 45 % owing the uniform distribution of interconnected pores with a mean pore size of 7.5 mu m. Well defined nanostructured cell walls with a mean grain size of 90 nm were observed in the above sample, which is in a good accordance with the grain size obtained from BET measurements. Saturation magnetization decreased from 2.31 in the Bi0.8Ba0.2FeO3 compact sample to 1.85 A.m2 /kg in urea-derived Bi0.8Ba0.2FeO3 porous sample; moreover, coercivity increased from 284 to 380 kA/m.

6

Factors influencing preparation of polyaniline doped with hydrochloric acid

Chuanyu S, Yu W.

Materials Science Poland

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2014

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Vol. 32, No. 4

521--525

EN

Factors influencing the reaction of chemical polymerization during aniline doping with hydrochloric acid (HCl) have been studied in this work. The optimal parameters for the preparation of polyaniline were determined as follows: aniline concentration – 4 mass %, molar ratios of oxidant (NH4)2S2O8:aniline – 1.2:1 and 1.3:1, the concentration of dopant – 1 mol/L. Fourier transform infrared spectroscopy (FT-IR) was applied to characterize the structure of polyaniline.

7

Synthesis of nanocrystalline Ni/Ce-YSZ powder via a polymerization route

Abolghasemi Z., Tamizifar M., Arzani K., Nemati A., Khanfekr A., Bolandi M.

Materials Science Poland

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2013

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Vol. 31, No. 3

343--349

EN

Pechini process was used for preparation of three kinds of nanocrystalline powders of yttria-stabilized zirconia (YSZ): doped with 1.5 mol% nickel oxide, doped with 15 mol% ceria, and doped with 1.5 mol% nickel oxide plus 15 mol% ceria. Zirconium chloride, yttrium nitrate, cerium nitrate, nickel nitrate, citric acid and ethylene glycol were polymerized at 80 A degrees C to produce a gel. XRD, SEM and TEM analyses were used to investigate the crystalline phases and microstructures of obtained compounds. The results of XRD revealed the formation of nanocrystalline powder at 900 A degrees C. Morphology of the powder calcined at 900 A degrees C, examined with a scanning electron microscope, showed that the presence of nickel and cerium inhibited the grain growth in the system. The average crystallite size of the material doped with nickel oxide (9.33 nm) was bigger than the one doped with cerium oxide (9.29 nm), while the YSZ doping with the two oxides simultaneously promoted the grain growth with crystallite size of 11.37 nm. Yttria-stabilized zirconia powder with a mean crystallite size of 9.997 nm was prepared successfully by this method.

8

Superplastic properties of zirconia-hafnia composites doped with various oxides

Boniecki M., Librant Z., Wesołowski W.

Materiały Ceramiczne

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2010

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T. 62, nr 3

259-265

EN

The influence of 1 mol% dopant of various oxides on the superplastic flow of yttria stabilized tetragonal zirconia ceramics and zirconia – 10 mol% hafnia composite was examined in the temperature range 1553–1773 K. It was claimed that doping caused the increase of superplastic strain rate in zirconia and in zirconia-hafnia composite in comparison with undoped materials. The maximum strain rate for zirconia was measured for GeO2 addition; it was 16x higher than in pure ceramics, but for zirconia-hafnia the maximum strain rate was for SiO2 dopant (4x higher than in pure composite). There is a linear relationship between the grain boundary diffusion coefficient of Zr4+ and superplastic strain rate for zirconia ceramics. For zirconia-hafnia composite this relationship is not so obvious because of high strain rate for SiO2 addition.

PL

Zbadano wpływ dodatku 1. % mol. różnych tlenków na nadplastyczne płynięcie ceramiki tetragonalnego dwutlenku cyrkonu stabilizowanego tlenkiem itru i kompozytu ZrO2-10 % mol. HfO2 w zakresie temperatury 1553–1773 K. Stwierdzono, że domieszkowanie spowodowało wzrost szybkości nadplastycznego odkształcania dwutlenku cyrkonu i kompozytu ZrO2-HfO2 w porównaniu z materiałami bez domieszek. Maksymalną szybkość odkształcania zmierzono w przypadku dodatku GeO2; była ona16x większa niż w czystej ceramice, ale w przypadku ceramiki ZrO2-HfO2 maksymalna szybkość odkształcania pojawiła się dla domieszki SiO2 (4x większa niż dla czystego kompozytu. Zależność pomiędzy współczynnikiem dyfuzji po granicach Zr4+ i nadplastyczną szybkością odkształcania ceramiki cyrkoniowej była liniowa. W przypadku kompozytu ZrO2-HfO2 zależność ta nie była tak oczywista z powodu wysokiej szybkości odkształcania zmierzonej dla dodatku SiO2.

9

Światłowód pierścieniowy domieszkowany neodymem.

Dorosz D.

Szkło i Ceramika

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2006

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R. 57, nr 2

14-18

EN

Signal processing, device oriented, ring-index fibers have a unique capability of transmitting either quasi planar modes for large ring diameters or the second order mode in a quasi single-mode regime at lossy discrimination of the fundamental mode, for small ring diameters. Ring-index fibres can maintain single mode transmission for considerable values of normalized frequency for particular cases of the refractive index profile. Theoretically predicted features of ring index fibres were confirmed experimentally on the samples manufactured by the author. The ring shape of doped rare earth core gives possibility to stimulate luminescence from inside of the fibre. In this paper the ring core doped Nd3+ ions fibre is reported. The analysis of dependences between parameters of core on light propagation in ring-core optical fibers is presented. The ring core is made from silica glasses doped by Nd3+ ions.

10

Investigations of Pr 3+ - doped fluoroindate glass. Synthesis, properties and applications

Pisarska J., Pisarski W.A.

Archiwum Nauki o Materiałach

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2004

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T. 25, nr 1

37-51

EN

Multicomponent fluoroindate glasses are promising materials for ultra-low loss mid-infrared optical fibers. Upon doping with rare earth ions, fibers are suitable for the development of blue lasers, tunable lasers, up-conversion lasers, high power laser materials and optical amplifiers for telecommunication systems. Characterization of glassy materials based on indium fluoride doped with Pr 3+ ions is reported using XRD, EPMA, DSC, IR and optical spectroscopy as well as their potential applications.

PL

Wieloskładnikowe szkła fluoroindowe są obiecującym materiałem do otrzymywania włókien optycznych mających zastosowanie w zakresie średniej podczerwieni. W wyniku aktywowania szkieł jonami ziem rzadkich stają się przydatne w konstrukcji lasera niebieskiego, konwertora promieniowania podczerwonego na światło widzialne, laserujących materiałów dużej mocy czy wzmacniaczy optycznych dla układów telekomunikacyjnych. W pracy przedstawiono charakterystykę szkieł opartych na fluorku indu domieszkowanych jonami prazeodymu. Badania przeprowadzono z zastosowaniem metod rentgenowskiej analizy fazowej (XRD), mikroanalizy rentgenowskiej (EPMA), różnicowej kalorymetrii skaningowej (DSC), spektroskopii w podczerwieni (R) i optycznej.

11

Relation between microstructure and grain boundary conductivity in yttria-doped zirconia.

Rizea A., Petot C., Petot-Ervas G., Kusinski J.

Inżynieria Materiałowa

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2001

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R. XXII, nr 5

784-786

EN

The microstructure grain boundary relation in yttria-doped zirconia has been investigated on polycrystals sintered from powders prepared through two different processing routes. Samples with no evidence for continuous glassy boundary films show the highest grain boundary conductivities (sigma gb) which decrease in presence of alumina additions. On the contrary, samples with boundary glassy films show an increase of sigma gb for small alumina additions (< or = 2 mole%) do likely to a change in the glass phase composition. The same sigma gb activation energy found for the different samples suggests that only "clean" grain-boundaries contribute to the transport processes.

12

Wybrane właściwości fizykochemiczne i optyczne szkieł fluorkowych domieszkowanych jonami metali przejściowych

Pisarska J., Żelechower M., Ryba-Romanowski W., Mazurak Z.

Inżynieria Materiałowa

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2000

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R. XXI, nr 4

141-144

PL

W pracy syntezowano szkła w złożonych układach wieloskładnikowych. Synteza prowadzona była w zaprojektowanej i wykonanej komorze do wytopów w atmosferze argonu, przy użyciu ultraczystych fluorków (zakupionych w Sigma Aldrich), w tyglu platynowym w temperaturze ~~850 stopni Celsjusza (w ciągu 1 h). Stop wylewano do podgrzanej do ~~250 stopni Celsjusza mosiężnej formy, wygrzewano w tej temperaturze, a następnie powoli chłodzono do temperatury pokojowej. Widma absorpcyjne rejestrowano przy pomocy spektrofotometru Varian Model 2300 UV-VIS-NIR. Próbki zawierające jony Eu i Tm wzbudzano za pomocą oscylatora parametrycznego (OPO) firmy Continuum Model Surelite I pompowanego trzecią harmoniczną lasera Nd:YAG firmy Continuum. Luminescencja z próbki analizowana była przez dwusiatkowy monochromator GDM-1000 firmy Carl Zeiss Jena i odbierana przez fotopowielacz. Sygnał z fotopowielacza podawany był na Boxcar Integrator Model SRS 250 firmy Stanford Research Systems. Przeprowadzona rentgenowska analiza fazowa, badania jednorodności składu chemicznego oraz pomiary właściwości optycznych wskazują na dobrą jakość uzyskanych szkieł.

EN

Rare earth elements doped fluoride glasses were formed in many elements systems. They were manufactured in dry box, in argon atmosphere with a use of ultrahigh purity fluorides (Sigma Aldrich) by melting their homogenised mixtures in a platinum crucible at ~~850 degrees centigrade. Liquid glass was poured to the preheated (250 degrees centigrade) brass mould then held at this temperature by 1 hour and then slowly cooled to the room temperature. XRD measurements showed a glassy structure of the resulted material, whereas EPMA measurements showed its chemical homogeneity. The understanding of the optical properties of rare earth ions in inorganic compouns is of great importance due to their potential technological applications, as, for example optical fibres, optical amplifiers, sensors and lasers. Fluoroindate glasses seem to be a particularly useful host for rare earth ions due to their optical quality and chemical stability. The studied fluoroindate glasses were based on indium fluoride InF3 as the network former and on various modifiers. Ideally, starting materials should be anhydrous fluorides of high purity. The samples obtained in this environment have good optical quality and chemical homogeneity. Optical absorption spectra have been recorded using Varian Model 2300 UV-VIS-NIR Spectrophotometer. Luminescence has been excited with a third harmonic of a Nd:YAG laser or with a Continuum Optical Parametric Oscillator. Luminescence spectra were recorded using a Stanford SRS 250 Boxcar Integrator connected to a personal computer. All spectroscopic measurements were carried out at room temperature.

13

On the defect structure of alkaline earth titanates.

Komornicki S.

Inżynieria Materiałowa

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1998

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R. XIX, nr 4

819-822

EN

Nonstoichiometry in strontium titanate as an example of alkaline earth titanates was discussed in terms of Sr/Ti ratio and dopant concentration and extended defect existence. For some dopant concentrations and titanium or strontium excess a self-compensation of cation and anion vacancies could be observed, leading to unusual pressure dependencies of electrical conductivity.

14

Non-equilibrium segregation in ceramic materials under a temperature gradient and microstructure.

Petot C., Monceau D., Petot-Ervans G.

Inżynieria Materiałowa

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1998

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R. XIX, nr 4

727-730

EN

An analyze of the transport processes in oxides, under a constant or variable (cooling) temperature gradient, has been performed in order to show the conditions leading to surface morphological instabilities and segregations. Because the properties of ceramics are often influenced by the presence of dopants or imputities and by their microstructure, these effects can severely alter the properties of materials and can be an important cause of ageing of ceramics when they are used at high temperature.<