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EN
Titanium dioxide thin films have been deposited on silicon wafers substrates by an atomic layer deposition (ALD) method. There optical parameters were investigated by spectroscopic ellipsometry and UV/VIS spectroscopy. A material with a refractive index of 2.41 was obtained. Additionally, in a wide spectral range it was possible to reduce the reflection from the silicon surface below 5%. The Raman spectroscopy method was used for structural characterization of anatase TiO2 thin films. Their uniformity and chemical composition are confirmed by a scanning electron microscope (SEM) energy dispersive spectrometer (EDS).
3
Content available remote Czarne chmury nad białym betonem
4
Content available remote Nano-modified cementing composites for self-cleaning building materials
EN
This paper is devoted to the development of nano-modified cementing composites in the field of self-cleaning building materials. Particle-size distributions of the main constituents such as ultra-fine zeolite and limestone of multicomponent cements, and titanium dioxide and kaolin additives are given. The degree of the interphase of the active surface in Portland cement and supplementary cementitious materials is calculated. It has been shown that due to the synergistic effect, anatase and rutile mixtures can be included in cementing composites to improve the properties of self-cleaning plasters. The influence of titanium dioxide and kaolin additives on the mechanical properties of nano-modified multicomponent cement was investigated using the method of mathematical planning for the experiment. The results obtained using the XRD and SEM methods showed that the addition of high-surface-area nano-scale particles of TiO2 to the cement paste leads to the formation of a denser microstructure in the cementing matrix.
5
EN
Cross-link method has been used to load nano CeO2, ZnO, and TiO2 on the surface of cotton fabric. Three types of nanocomposite fabrics are prepared (cotton/CeO2, cotton/CeO2/ZnO, and cotton/CeO2/TiO2) and their properties were investigated. Field emission scanning electron microscopic (FESEM) images of the samples showed good distribution of nanomaterial, and energy dispersive X-ray spectroscopy (EDX) and X-ray fluorescence (XRF) samples proved the usage of amount of nanomaterials. On the other hand, elemental mapping was used to study the distribution of each nanomaterial separately. Antibacterial property of the samples showed excellent results against both Gram-negative and Gram-positive bacteria. Also ultraviolet (UV)-blocking of treated samples showed that all samples have very low transmission when exposed to UV irradiation.
EN
Purpose: The influence of UV radiation on the antibacterial properties of titanium oxide nanoparticles was examined using yeast Saccharomyces cerevisiae strain for this purpose. Design/methodology/approach: Nanopowders were made with sol-gel method. Surface morphology studies of the obtained materials were made using Zeiss's Supra 35 scanning electron microscope. In order to confirm the chemical composition of observed nanopowders, qualitative tests were performed by means of spectroscopy of scattered X-ray energy using the Energy Dispersive Spectrometer (EDS). The DLS (Dynamic Light Scattering) method was used to analyse the particle size distribution using the AntonPaar Litesizer 500 nanoparticle size analyser. Changes in particle size distribution at elevated temperatures were also observed. The antibacterial properties of titanium oxide nanoparticles were examined by subjecting the yeast sample to irradiation with an UV lamp. Findings: Samples containing yeast Saccharomyces cerevisiae were irradiated with and without the addition of TiO2 nanoparticles. A faster decrease in the colony count was observed compared to irradiated exposures without the addition of a suspension. Practical implications: Presented materials can be used in the production of antibacterial coatings for surfaces occurring in public spaces such as schools, hospitals, public toilets for the simple and effective elimination of bacteria and fungi as a result of exposures. Originality/value: The antibacterial properties of titanium oxide nanoparticles under UV radiation were confirmed.
EN
Nano-sized Y- Ag doped and co-doped TiO2 particles were synthesized using the sol–gel method and Ti(OBu)4 as TiO2 precursor. Their structural and optical properties were examined by scanning electron microscopy (SEM), XRD, thermogravimetric-differential thermal analysis (TG-DTA), FT-IR and UV-vis absorption spectroscopies. The photocatalytic activity of these materials was investigated for the photodegradation of methylene blue (MB) as a model reaction under visible light irradiation. Ground state diffuse reflectance absorption studies reveal that both Y and Ag dopant cause deviations of the band gap to higher energies attesting that co-doping the TiO2 with Y and Ag could enhance the photocatalytic activity by delaying the electron–hole recombination by means of higher energy band gaps. Co-doping TiO2 at a level of 4% (Y, Ag) samples leads to a significant decrease in the crystallite size of photocatalyst and containing both anatase and Ag/AgCl components. However, the high photocatalytic performance is attributed to an efficient electron-hole pairs separation at the photocatalyst interfaces in addition to localized surface plasmon resonance of Ag particles. The development of these visible light- activated nanocatalysts has the potential of providing environmentally benign routes for water treatment.
EN
Anatase, as an important titanium resource, is attracting more and more attention in research and application. In this study, an efficient process of comprehensively extracting the titanium and other valuable elements from the anatase mineral was proposed. The effect of particle size, stirring speed, initial sulphuric acid concentration, solid-to-liquid ratio, and reaction temperature on the leaching rate of titanium from anatase was investigated. Under appropriate two-stage countercurrent leaching conditions, with the first stage of the liquid-to-solid ratio of 1/3 g/cm3, reaction temperature of 120 °C, initial acid concentration of 11 mol/dm3, residence time of 30 min, stirring speed of 200 rpm, and the second stage of the liquid-to-solid ratio of 1/3 g/cm3, reaction temperature of 200 °C, initial acid concentration of 13 mol/dm3, residence time of 30 min, and stirring speed of 200 rpm, over 99% TiO2, 99% Al2O3, and 97% Sc2O3 were extracted respectively with quartz still remained in the residue. X-ray diffraction, X-ray fluorescence spectrometer, and scanning electron microscopy/energy-dispersive spectroscopy were used to characterize the anatase samples before and after the leaching. Additionally, the leaching kinetics analysis indicated that both acid concentration and temperature were the most significant parameters for the leaching process. And, the titanium leaching reaction rate was controlled by the diffusion of reactants through the residual layer.
EN
The production of preparations, whose destination action takes place in close proximity to living cells, increases the necessity to carry out studies concerning the determination of the biomaterial surface effect on the cellular response. In achieving this goal, physicochemical characteristic of the surface can be helpful. This can be established based on topography, chemical composition, wettability, and surface energy analysis. In addition, determining the changes of these properties which can occur as a result of surface modification will allow prediction of cell behaviour when contacting with biomaterial. In the study, the Langmuir-Blodgett technique was used. It enabled the transfer of the Langmuir monolayer formed from 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) to a solid support. The DPPC film imitated a natural biological membrane capable of interacting with the components of the liquid subphase: chitosan (Ch), hyaluronic acid (HA) and/or titanium dioxide (TiO2). Depending on the type and strength of interactions of phospholipid molecules with the components of the subphase, the films obtained on the solid support were characterized by specific surface properties. Their characteristics based mainly on values of the work of adhesion in connection with films topography, allowed for statement that it is possible to form semi-interpenetrating Ch network in which HA is entrapped, contributing to the enhanced adhesion of the DPPC film, additionally intensified by TiO2 inclusion. This type of research permit for better understanding of the interactions at the interface, cell membrane-Ch/HA/TiO2 and can be important in the creation of a new generation of skin or tissue substitutes.
PL
Kompozyt polianilina-rdzeń-nano-TiO2 został przygotowany w procesie polimeryzacji strąceniowej polianiliny w środowisku dwóch różnych kwasów nieorganicznych. Testy korozyjne zostały wykonane na podłożu ze stali S235JR pokrytej spoiwem alkidowym (jednowarstwowo, przy użyciu aplikatora ramkowego) zawierającym 0,5%mas badanego kompozytu, spoiwem alkidowym zawierającym 0,5%mas pigmentu na bazie polianiliny z rdzeniem oraz handlowego, antykorozyjnego spoiwa alkidowego. Badania w komorze solnej zostały wykonane zgodnie z normą PN-EN 9227:2012, a badania EIS wg normy PN-EN ISO 16773-2:2008. Testy EIS prowadzone były przez sześć tygodni z cotygodniowym pomiarem impedancji. Wyniki wskazują na najwyższą odporność antykorozyjną dla farb z wprowadzonym pigmentem na bazie polianilina-rdzeń-nano-TiO2, szczególnie dla kompozytów otrzymywanych w środowisku kwasu solnego.
EN
The polyaniline-core-nano-TiO2 composites were prepared by in situ oxidative polymerization of aniline in solutions of two different inorganic acids. The corrosion tests were carried out on carbon steel substrates coated by alkyd coatings (using frame film applicator, one-coat application) containing as the anticorrosion pigments 0.5 mass% of these composites in comparison to coating modified with the same amount of polyaniline composites. The salt spray and EIS (Electrochemical Impedance Spectroscopy) investigations were carried out according to the PN-EN 9227:2012 and PN-EN ISO 16773-2:2008 standards. The EIS test was performed for six weeks, with weekly impedance measurements. The results showed highest anticorrosion resistance of coatings modified with PANI-zinc-oxalate-nano-TiO2 composites, especially the composite obtained in solution of hydrochloric acid.
EN
Titanium dioxide is the most important photocatalyst used in the processes of the photocatalytic water treatment. Unfortunately, preparation of this material is energy consuming and requires application of toxic reagents, which is unfriendly to the environment. In this studies, TiO2 materials were biosynthesized using extracts form shamrock and walnut leafs to replace harmful compounds. Different TiO2 precursors were used: 1) titanium tetraizopropoxide (TTIP), 2) an intermediate product from titanium dioxide technological line in Grupa Azoty Zakłady Chemiczne “Police” SA. To prepare titanium dioxide, the individual extract was mixed with distilled water and titania precursor. The photocatalytic properties of prepared materials were tested in the reaction of decomposition of the model compound Acid Red 18, being an organic azo dye. The results revealed that the material prepared with TTIP shows the highest activity from all studied materials and decomposed the dye in 55 min. Application of various plant extracts has no much impact on the photoactivity of TiO2 photocatalyst — both materials decomposed Acid Red 18 in 55 min. Prepared materials were characterized by X-ray diffraction, nitrogen adsorption/ desorption process, diffuse reflectance UVVis and FTIR spectroscopy. Summarizing, each prepared material showed high photocatalytic activity so this preparation method seems to be appropriate for synthesis of active titania photocatalyst.
PL
Fotokataliza jest jedną z metod oczyszczania wody, która w ostatnich latach wzbudza coraz większe zainteresowanie naukowców, gdyż w większości przypadków powoduje rozkład zanieczyszczeń do wody, ditlenku węgla oraz kwasów nieorganicznych. Spośród wielu typów stosowanych fotokatalizatorów najczęściej badany jest ditlenek tytanu (TiO2), ponieważ charakteryzuje się dużą fotoaktywnością i stabilnością chemiczną, dobrymi właściwościami optycznymi, a co najważniejsze jest tani i łatwo dostępny. Niestety wytwarzanie tego materiału wymaga dużych nakładów energetycznych i zastosowania szkodliwych związków, co jest niekorzystne dla środowiska. Dlatego poszukuje się nowych, efektywnych i przyjaznych dla środowiska metod wytwarzania zarówno TiO2, jak i innych półprzewodników. Odpowiednią do tego metodą wydaje się biosynteza z użyciem ekstraktów roślinnych, ponieważ jest prosta, bezpieczna i przyjazna środowisku. W artykule przedstawiono nową metodę preparatyki TiO2: biosyntezę z użyciem ekstraktów z koniczyny białej i z liści orzecha włoskiego. W celu porównania użyto różnych prekursorów ditlenku tytanu: 1) tatraizopropanolanu tytanu (TTIP), 2) półproduktu z linii produkcyjnej TiO2 Zakładów Chemicznych „Police” SA: nieoczyszczonego (IP(A)) oraz płukanego wodą amoniakalną i wodą destylowaną (IP(W)). Właściwości fotokatalityczne wytworzonych materiałów sprawdzono, przeprowadzając szereg reakcji rozkładu związku modelowego: pąsu kwasowego (AR18), który jest barwnikiem azowym stosowanym głównie w przemyśle tekstylnym.
EN
The occurrence of contaminants of emerging concern (CECs) such as pharmaceutical compounds (PhACs) is becoming a major global issue due to the persistence, bioaccumulation, and toxicity of these pollutants. Human and animal consumption was recognized as the major sources for pharmaceutical pollution. Existent conventional treatment processes have shown low degradation efficiencies towards PhACs. In this regard, TiO2 based nanocomposite photocatalysis process has presented effective degradation towards PhACs. Operational parameters such as dopant content, catalyst loading, and initial pH were the major factors in the photocatalysis system. In this review, we discuss the recent studies that have employed TiO2 based nanocomposite for the degradation of PhACs. Future research recommendations have also been elaborated.
EN
Purpose: The article presents the results of research on titanium dioxide synthesized by a sol-gel method that is an easy process enabling the control of the shape and size of particles The purpose of this article is to examine titanium dioxide nanoparticles and thin films deposited by an atomization method. Design/methodology/approach: Titanium dioxide sol was synthesized by using titanium isopropoxide as a precursor. Optical properties were measured by a UV-Vis spectrometer. Structural studies were performed by Raman spectroscopy. Qualitative analysis was performed by the EDS. Surface morphology of nanoparticles and thin films was performed by the SEM technique. Findings: The sol-gel method allows the formation of uniform nanoparticles and thin films of titanium dioxide. The atomization method is a successful method for the deposition of sol to the surface of substrates. Research limitations/implications: The next step in the research will be to investigate the obtained thin films in dye-sensitized solar cells as a semiconductive layer. Practical implications: Unique properties of produced titanium dioxide nanostructural materials have caused the interest in them in such fields as optoelectronics, photovoltaics, medicine and decorative coatings. Originality/value: Titanium dioxide thin films and nanoparticles were synthesized using the sol-gel method and then deposited by the atomization method.
EN
The advance in the nanotechnology and fabrication of micro- and nanostructures has significant impact on development of new optical sensors. Presented study focuses on the applications of the titanium dioxide (TiO2) thin films in fiber optic sensors. The concept of a sensing fiber optic interferometer integrating TiO2 thin film is presented. The cavity of this interferometer is delimited by a 80 nm film fabricated on the end-face of the standard telecommunication single mode optical fiber (SMF-28) by use of the Atomic Layer Deposition (ALD) and a protected silver mirror. The simulation of spectral reflectance of the thin film is performed and its performance in a multi-cavity structure of the fiber optic Fabry-Pérot interferometer is analyzed. The results show that proposed interferometer could be successfully implemented in optical fiber sensors of selected physical and biochemical quantities.
PL
Rozwój nanotechnologii i możliwości wytwarzania mikro- i nanostruktur otworzyło nowe możliwości w projektowaniu czujników optycznych. Poniższa praca skupia się na zastosowaniach cienkich warstw dwutlenku tytanu (TiO2) w czujnikach światłowodowych. Zaprezentowana została koncepcja czujnika interferometrycznego wykorzystującego takie warstwy. Projekt sensora światłowodowego zakłada 82 nm warstwę osadzoną na czole standardowego jednomodowego włókna telekomunikacyjnego (SMF28) dzięki wykorzystaniu metody osadzania warstw atomowych (Atomic Layer Deposition (ALD) ). Przeprowadzone i zaprezentowane zostały wyniki modelowania reflektancji cienkiej warstwy w tej konfiguracji oraz przeanalizowany jej wpływ na pracę w konfiguracji wielownękowego interferometru Fabry-Pérot. Wyniki pozwalają stwierdzić, że zaproponowana konstrukcja może być z sukcesem zaimplementowana w czujniku interferometrycznym.
PL
Powłoki funkcjonalne nakładane na szkło modyfikują jego cechy lub nadają mu zupełnie nowe właściwości, zmieniając jednocześnie właściwości optyczne całego układu (warstwa/warstwy-podłoże). Interferencyjne kolorowe powłoki dekoracyjne typu TiO2/Ti/TiO2/szkło otrzymano z zastosowaniem magnetronu przemysłowego. Świetlne właściwości otrzymanych układów określono zgodnie z normą PN-EN 410. Wykazano, że zarówno grubości warstw TiO2, jak i Ti znacząco wpływają na parametry zdefiniowane w wyżej wymienionej normie.
EN
Functional coatings deposited on glass modify its features or give it completely new properties, simultaneously changing optical properties of the whole system (layer/layers-substrate). Interference decorative TiO2/Ti/TiO2/glass coatings were produced using magnetron sputtering technique at industrial conditions. Luminous properties of the obtained systems were determined according norm EN 410. Showed that thickness of both TiO2 and Ti significantly have an influence on parameters defined in the above mentioned norm.
EN
Pharmaceutical pollutants have been detected in many countries in surface and ground water after treatment in wastewater treatment plants. The presented studies concern the photocatalytic removal of one of SSRI antidepressants - sertraline from water using TiO2  photocatalyst. The process was conducted using two laboratory installations with periodic and flow reactors. Two forms of TiO2  was used in the photocatalytic reactions: suspended and supported onto a glass fabric. The studies shown that with increasing initial concentration of pharmaceutical, photoactivity decreases. For the initial concentration of 0.025 g/dm3 , the best results – 94% removal – was achieved for the process conducted in the periodic reactor with TiO2  supported onto a glass fabric.
17
Content available remote Wykorzystanie odpadu z produkcji bieli tytanowej jako dodatku do betonu
PL
W artykule przedstawiono wyniki badań, których celem było wykazanie możliwości stosowania odpadu z produkcji bieli tytanowej jako dodatku do betonu (badania były prowadzone w ramach pracy badawczej oceniającej możliwość wykorzystania ilmenitowego szlamu porozkładowego jako reaktywnego dodatku do betonu). Prezentowane wyniki dotyczą badań „typowych” betonów towarowych o projektowanej klasie wytrzymałości C16/20. Badano ich wytrzymałość na ściskanie oraz na rozciąganie przy zginaniu, skurcz liniowy i nasiąkliwość oraz strukturę. W tym celu wykorzystano mikroskop skaningowy z analizą w mikroobszarze (SEM+EDS), która wykazała, że w przypadku określonych parametrów badane betony C16/20 z dodatkiem ilmenitowego szlamu porozkładowego cechują nie gorsze właściwości niż betonów referencyjnych z dodatkiem popiołu lotnego.
EN
The article presents the results of tests which aim was to determine the possibility of using a waste from the production of titanium dioxide as an additive for concrete (the tests were carried out as a part of project which aim was the evaluation of the valorization of the waste material from the production of titanium white as an active additive for concretes). Presented results were carried out on the “typical” ready-mixed concrete with a compressive strength class C16/20. The tests of compressive strength, bending strength, linear shrinkage and absorptivity of concrete have been performed. Also, the structural analysis was made using scanning electron microscope with microanalysis by energy dispersive spectroscopy (SEM+EDS). The results showed that the chosen technical properties of concretes with addition of ilmenite mud waste were as good as the properties of reference concrete with addition of fly ash.
18
Content available remote Ocena możliwości redukcji tlenków azotu przez beton fotokatalityczny
PL
W artykule omówiono zastosowanie betonu fotokatalitycznego w kontekście redukcji stężenia tlenków azotu w powietrzu. Opisano mechanizm procesu fotokatalizy i metody badań skuteczności tego rozwiązania. Przedstawiono również przykłady realizacji z użyciem betonu fotokatalitycznego oraz wymieniono czynniki wpływające na efektywność redukcji tlenków azotu.
EN
The paper presents the use of photocatalytic concrete in the context of reducing the concentration of nitrogen oxides in the air. The mechanism of the photocatalysis process and research methods on the effectiveness of this solution are described. Examples of realizations using photocatalytic concrete and factors influencing the effectiveness of reduction of nitrogen oxides are also presented.
EN
Titanium dioxide (TiO2) is one of the most favored metal oxide semiconductors for the use as photoanode in photoelectrochemical cells (PEC) splitting the water into hydrogen and oxygen. However, the major impediment is its large bandgap that limits its utilization as photoanode. Doping has evolved as an effective strategy for tailoring optical and electronic properties of TiO2. This paper describes the synthesis of undoped as well as iron (Fe, cationic) and nitrogen (N, anionic) doped nanocrystalline titanium dioxide by sol-gel spin coating method for solar energy absorption in the visible region. All the prepared thin films were characterized by X-ray diffraction and UV-Vis spectroscopy. Doping of both Fe and N into TiO2 resulted in a shift of absorption band edge towards the visible region of solar spectrum.
PL
Celem artykułu jest przedstawienie wpływu wypełniaczy w postaci nanomateriałów w obecności lub bez domieszek chemicznych na właściwości reologiczne mieszanek na spoiwach cementowych wraz z przeglądem modeli opisujących ww. właściwości reologiczne mieszanek.
EN
The aim of the article is to present the effect of nanomaterial fillers in the presence or absence of chemical admixtures on the rheological properties of cementitious binder mixtures along with the review of models describing the above-mentioned rheological properties of mixtures.
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