Photocatalytic porcelain grés large slabs digitally coated with AgNPs-TiO2

TiO2 is employed as both photocatalytic and structural materials, leading to its applications in external coatings or in interior furnishing devices, including cement mortar, tiles, floorings, and glass supports. The authors have already demonstrated the efficiency of photoactive micro-sized TiO2 and here its industrial use is reported using the digital printing to coat porcelain gr\ue9s slabs. Many advantages are immediately evident, namely rapid and precise deposition, no waste of raw materials, thus positively affecting the economy of the process. Data for the thin films deposited by digital printing were compared with those obtained for the conventional spray method. The use of metal-doped TiO2 is also reported so that the photoactivity of these materials can be exploited even under LED light. The digital inkjet printed coatings exhibited superior photocatalytic performance owing to both higher exposed surface area and greater volume of deposited anatase, as well as the greater areal distribution density of thinly and thickly coated regions. Moreover, the presence of TiO2 doped silver increased the efficiency of the materials in NOx degradation both under UVA and LED lights

Continuous Photocatalytic Antibacterial Activity of AgNPs doped TiO2 Digital Printed on Commercial Porcelain-grès Tiles

Photocatalytic finishing materials, such as tiles or paints, are a productive as well as scientific reality. One of the most interesting photocatalytic material currently on the market is the porcelain stoneware which combines the beauty of a design product with hardness and absence of porosity and thus used for both floors and walls. The Ag- micrometric TiO2 allowed active ceramic slabs to be active under LED lights, bypassing the problem of the UVA radiation. SEM/TEM images in Fig. 1 indicate the full coverage of the porcelain surface (left image), besides a nanometric though heterogenous spreading of the AgNPs on top of the TiO2 matrix (right image). Figure 1. HR-SEM of the Active ceramic surface (left), TEM image of 8% AgNPs-TiO2(center); possible photocatalytic mechanistic pathways in Ag doped TiO2 system (right) An important question concerns the antibacterial action: in fact, today the role of silver is unknown when the metal is physically blocked on a surface and cannot penetrate and therefore interfere at the DNA level in the cellular barrier. The prepared porcelain Ag-TiO2 printed surfaces were tested against E. coli under solar and visible illumination and in the dark. To differenciate the semicondutor behavior and the ions mediated bacterial inactivation mechanism, porinless E. coli were used under band-gap irradiation. Stereomicroscopy analysis showed dead bacteria within 180 and 240 min respectively for normal E. coli and porinless E. coli. Using appropriate quenchers, the bacterial inactivation mechanisms under solar and visible light are proposed

Porcelain gres tiles with photocatalytic properties for a better environment

Porcelain gres tiles are characterised by their very low water absorption rate of less than 0.5%, and are manufactured under high pressure by dry-pressing fine processed ceramic raw materials with large proportions of quartz, feldspar and other fluxes. Afterwards, the body of these materials is fired at high temperatures (1200 - 1300\ub0C) in a roller kiln. The final material is characterized by lack of porosity, durability, high breaking and wear resistance properties and a complete frost resistance. In the past decades porcelain gres tiles underwent significant transformations in terms of appearance and size. At the beginning of the industrial productions, porcelain gres tiles were considered as just a technical material characterized by strong resistance to both abrasion and acid attack, almost lack of porosity, but aesthetically not very beautiful. Today thanks to new industrial production methods, both properties and beauty of these materials completely fit the market requests. In particular, the possibility to prepare slabs of large sizes is the new frontier of the building materials. Beside these noteworthy architectural features, new surface properties have been introduced in the last generation of these materials. The present paper reports the research at the base of a new kind of fired tiles able to carry out a specific antibacterial and self-cleaning action and to reduce polluting molecules thanks to its new photocatalytic properties due to the surface presence of photoactive micro-TiO2

Impact of atrial fibrillation in critically ill patients admitted to a stepdown unit

Background: Limited data are available on the clinical course of patients with history of atrial fibrillation (AF) when admitted in an intensive care environment. We aimed to describe the occurrence of major adverse events in AF patients admitted to a stepdown care unit (SDU) and to analyse clinical factors associated with outcomes, impact of dicumarolic oral anticoagulant (OAC) therapy impact and performance of clinical risk scores in this setting. Materials and methods: Single-centre, observational retrospective analysis on a population of subjects with AF history admitted to a SDU. Therapeutic failure (composite of transfer to ICU or death) was considered the main study outcome. Occurrence of stroke and major bleeding (MH) was considered as secondary outcomes. The performance of clinical risk scores was evaluated. Results: A total of 1430 consecutive patients were enrolled. 194 (13.6%) reported the main outcome. Using multivariate logistic regression, age (odds ratio [OR]: 1.03, 95% confidence interval [CI]: 1.01-1.05), acute coronary syndrome (OR:3.10, 95% CI: 1.88-5.12), cardiogenic shock (OR:10.06, 95% CI: 5.37-18.84), septic shock (OR:5.19,95%CI:3.29-18.84), acute respiratory failure (OR:2.49, 95% CI: 1.67-3.64) and OAC use (OR: 1.61, 95% CI: 1.02-2.55) were independently associated with main outcome. OAC prescription was associated with stroke risk reduction and to both MH and main outcome risk increase. CHA2 DS2 -VASc (c-index: 0.545, P = .117 for stroke) and HAS-BLED (c-index:0.503, P = .900 for MH) did not significantly predict events occurrence. Conclusions: In critically ill AF patients admitted to a SDU, adverse outcomes are highly prevalent. OAC use is associated to an increased risk of therapeutic failure, clinical scores seem unhelpful in predicting stroke and MH, suggesting a highly individualized approach in AF management in this setting

Supplementary data for the article: Stojković, D. L. J.; Bacchi, A.; Capucci, D.; Milenković, M. R.; Čobeljić, B.; Trifunović, S. R.; Andelković, K.; Jevtić, V. V.; Vuković, N.; Vukić, M.; et al. Synthesis and Characterization of Palladium(II) Complexes with Glycine Coumarin Derivatives. Journal of the Serbian Chemical Society 2016, 81 (12), 1383–1392. https://doi.org/10.2298/JSC160915087S

Supplementary material for: [https://doi.org/10.2298/JSC160915087S]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2392

Phenol photodegradation in presence of nano or micro-TiO2: performance comparison and study of the different by-products

In the present work the degradation of phenol in water was performed comparing the use of a commercial micro-sized TiO2 (1077 by Kronos) with a nano-TiO2 (P25 by Evonik), as well as with commercially available photoactive porcelain gr\ue9s tiles; in particular, the photoefficiency of the micro-sized sample was evaluated both as powder form and immobilized on tiles, in order to make a comparison and point out the main differences and changes in term of diffusion of the pollutant, absorption, photoactivity and efficiency

Copper NPs decorated titania to improve the photoactivity under visible light: a novel synthesis by high energy US

Different samples of commercial and micrometer TiO2 were decorated with copper nanoparticles by means of high-energy ultrasounds, and they were tested on the photodegradation of VOC\u2019s in gas phase under visible light, studying in particular the effect of the copper amount first, and also the difference performances using a LED lamp at different irradiation power. The results are consistent with the characterization data, showing an increase of the photoactivity and the absorption in the visible spectra with the increase of the copper amount, but only up to a certain value

Micro-sized TiO2 catalyst in powder form and as coating on porcelain grès tile for the photodegradation of phenol as model pollutant for water phase

In presence of TiO2 and irradiation, phenol can be degraded by hydroxyl radicals or directly via photogenerated carriers, as occurs in photocalytic processes. In this work a commercial micro-sized TiO2 sample in powder form and industrially coated on porcelain gr\ue8s tiles were tested in water remediation with phenol as model molecule. Firstly, we investigated the behaviour of the commercial micro-sized TiO2 comparing the results with reference nano-sized catalyst in the phenol photodegradation process, widely studied in the last decades. Following the phenol concentration as well as the main intermediates formation over time by HPLC analysis, and the mineralization by TOC analysis, we presented results about the photocatalytic behaviour in terms of adsorption, by-products formation, and reaction rate at different phenol starting concentrations. In particular, with the photocatalytic tiles, phenol photodegradation percentage is almost the same at 15 ad 25 ppm (78% and 73% respectively), and much lower at 50 ppm (46%) after 6 hours of test