Search results for "visual_art"

Influence of sol counter-ions on the visible light induced photocatalytic behaviour of TiO2 nanoparticles

2014

Titanium dioxide (TiO2) nanoparticles are attracting increasing interest because of their superior photocatalytic and antibacterial properties. Here, aqueous titanium oxy-hydroxide sols were made, using a green synthesis method, from the controlled hydrolysis/peptisation of titanium isopropoxide. Three different mineral acids were used to peptise the sol (HNO3, HBr and HCl), and provide counter-ions. The influence of nitrate or halide sol counter-ions on size distributions of the starting sols were measured via photon correlation spectroscopy (PCS). Semi-quantitative phase composition analysis (QPA), on the gels thermally treated at 450 and 600 degrees C, was carried out via Rietveld refine…

Microanalytical characterization of decorations in handmade ancient floor tiles using inductively coupled plasma optical emission spectrometry (ICP-O…

2013

In this study a total of 114 glazed decorations of 42 ceramic floor tiles, manufactured in Sicily fromthe 16th to 19 the 21th AD, were investigated. The micro sampling method, proposed by us, using a cotton swab soaked in hydrofluoric acid, includes advantages of high sensitivity, high selectivity, simplicity, speed, not expensive and can be considered non-destructive because the point of sampling remains invisible to the human eye. ICP-OES technique was used in this study. Twenty-four elements (Al, As, B, Be, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Mo, Ni, Pb, Sb, Se, Si, Sn, Ti, V and Zn) were determined in each colored enamel. Enameled decorations in Sicilian tiles were varied in tones an…

Trapped metal cluster ions

1995

An overview is given of experiments with stored metal cluster ions in a Penning trap system. The setup allows axial injection of clusters produced in an external source and a time-of-flight mass analysis of the reaction products after axial ejection. The system's options include the selection of stored ions, the manipulation of their orbits, addition of reactant and buffer gases and axial optical access for laser spectroscopic studies. As described by various examples, investigations have been made with respect to the development of trapping techniques and the characterization of metal clusters in terms of their physical and chemical properties.

Laser Ultrasonic Testing for Estimation of Adhesion of Al2O3Plasma Sprayed Coatings

2001

Abstract The aim of the present study was to investigate the possibility of using a laser ultrasonic technique for the estimation of the adhesion of ceramic coatings, deposited onto metallic substrates by thermal spraying techniques. For this purpose, a pulsed Nd : YAG laser (λ = 1064 nm, 14 ns) was used to irradiate Al2O3 coatings, of different thickness (30–350 µm), deposited onto stainless steel substrates by atmospheric plasma spraying. The laser generated ultrasonic waves were in situ recorded at the epicentre using a laser heterodyne interferometer. The acoustic waveforms were correlated with the interaction between the pulsed laser radiation and the coated metal, taking into account …

Anomalous Valence Contrast of Metal Transition in Nanocrystalline Ferrite

2001

Effects of treatment with three types of varnish remineralizing agents on the microhardness of demineralized enamel surface

2019

Background Remineralization of incipient caries is one of the goals in dental health care ,especially in pediatric dentistry. The present study aimed at comparing the effects of MI varnish (3M (United states)) , Nano paste( FGM(Brezil) ), 5% sodium fluoride varnish) DuraphatColgate (united states) ) on remineralization of enamel lesions. Material and Methods In this in-vitrostudy, 60 intact human pre-molars, were randomly allocated to four groups of 15. Baseline surface microhardness in three points in the center of the polished area was measured. After two days of immersion in demineralizing solution, microhardness of all samples was measured. Afterward, groups 1-3 under-went treatment wit…

Effect of addition of bioactive glass to resin modified glass ionomer cement on enamel demineralization under orthodontic brackets

2019

Background Enamel demineralization and white spot lesions around orthodontic brackets is a common problem associated with fixed orthodontic treatment. Glass ionomer cements (GICs) are commonly used for bracket bonding and recently, bioactive glass (BAG) was added to GICs to enhance deposition of calcium phosphate in adjacent dental structure. This study sought to assess the effect of addition of BAG particles to resin modified GIC (RMGIC) on enamel demineralization under orthodontic brackets. Material and methods In this in vitro, experimental study, 60 sound human premolars were immersed in distilled water at 6°C. The teeth were randomly divided into three groups. Using a sticker, a window…

Metal Hydride-Based Hydrogen Storage Tank Coupled with an Urban Concept Fuel Cell Vehicle: Off Board Tests

2018

VALORISATION OF FOREST AND AGRICULTURAL BIOMASS FOR THE SPANISH CERAMIC TILE INDUSTRY

2015

Since ceramic tile industry is an energy intensive industry, European ceramic companies are challenged to reduce their CO2 emissions in the medium and long-term. According the Roadmap for moving to a low-carbon economy in 2050 (European Commission, 2011) the objective is to achieve a reduction in CO2 emissions of between 34 % and 40 % by 2030, and between 83 % and 87 % by 2050. In the present paper we present a study on the viability of the incorporation of biofuels in the energy mix of the Spanish ceramic industry with the objective of (1) identifying the potential use of biomass resources, with a special focus of forest and agricultural biomass, in the manufacturing process of ceramic til…

Correction: Variation of the Fermi level and the electrostatic force of a metallic nanoparticle upon colliding with an electrode.

2017

The nanoparticle potential varies with the distance from the electrode, and sometimes like attracts like.