115 research outputs found
From Data to Phenomena: A Kantian Stance
This paper investigates some metaphysical and epistemological assumptions behind Bogen and Woodward's data-to-phenomena inferences. I raise a series of points and suggest an alternative possible Kantian stance about data-to-phenomena inferences. I clarify the nature of the suggested Kantian stance by contrasting it with McAllister's view about phenomena as patterns in data sets
Two-Functional Direct Current Sputtered Silver-Containing Titanium Dioxide Thin Films
The article reports on structure, mechanical, optical, photocatalytic and biocidal properties of Ti–Ag–O films. The Ti–Ag–O films were reactively sputter-deposited from a composed Ti/Ag target at different partial pressures of oxygen on unheated glass substrate held on floating potentialUfl. It was found that addition of ~2 at.% of Ag into TiO2film has no negative influence on UV-induced hydrophilicity of TiO2film. Thick (~1,500 nm) TiO2/Ag films containing (200) anatase phase exhibit the best hydrophilicity with water droplet contact angle (WDCA) lower than 10° after UV irradiation for 20 min. Thick (~1,500 nm) TiO2/Ag films exhibited a better UV-induced hydrophilicity compared to that of thinner (~700 nm) TiO2/Ag films. Further it was found that hydrophilic TiO2/Ag films exhibit a strong biocidal effect under both the visible light and the UV irradiation with 100% killing efficiency ofEscherichia coliATCC 10536 after UV irradiation for 20 min. Reported results show that single layer of TiO2with Ag distributed in its whole volume exhibits, after UV irradiation, simultaneously two functions: (1) excellent hydrophilicity with WDCA < 10° and (2) strong power to killE. colieven under visible light due to direct toxicity of Ag
New Insights into the Mechanism of Visible Light Photocatalysis
ABSTRACT: In recent years, the area of developing visible-lightactive photocatalysts based on titanium dioxide has been enormously investigated due to its wide range of applications in energy and environment related fields. Various strategies have been designed to efficiently utilize the solar radiation and to enhance the efficiency of photocatalytic processes. Building on the fundamental strategies to improve the visible light activity of TiO2-based photocatalysts, this Perspective aims to give an insight into many contemporary developments in the field of visible-light-active photocatalysis. Various examples of advanced TiO2 composites have been discussed in relation to their visible light induced photoconversion efficiency, dynamics of electron− hole separation, and decomposition of organic and inorganic pollutants, which suggest the critical need for further development of these types of materials for energy conversion and environmental remediation purposes
What’s in It for the Historian of Science? Reflections on the Value of Philosophy of Science for History of Science
In this article, I explore the value of philosophy of science for history of science. I start by introducing a distinction between two ways of integrating history and philosophy of science: historical philosophy of science (HPS) and philosophical history of science (PHS). I then offer a critical discussion of Imre Lakatos’s project to bring philosophy of science to bear on historical interpretation. I point out certain flaws in Lakatos’s project, which I consider indicative of what went wrong with PHS in the past. Finally, I put forward my own attempt to bring out the historiographical potential of philosophy of science. Starting from Norwood Russell Hanson’s insight that historical studies of science involve metascientific concepts, I argue that philosophical reflection on those concepts can be (and, indeed, has been) historiographically fruitful. I focus on four issues (epistemic values, experimentation, scientific discovery and conceptual change) and discuss their significance and utility for historiographical practice. © 2017 Open Society Foundation
Enhanced activity of silver modified thin-film TiO2 photocatalysts
Novel, composite silver/titania immobilized on glass substrates were prepared, characterized
and their photocatalytic activity was evaluated. The undoped original material consists of rough, high surface
area nanocrystalline titanium dioxide (TiO2) thin films. To increase their efficiency, the TiO2 films were
modified by silver cations deposition and subsequent UV-C irradiation. SEM pictures confirmed the existence
of an open porous network of interconnected titania particles on the semiconductor surface. AFM
analysis proved the presence of spherical silver particles on the catalyst surface and provided quantitative
surface parameters as fractal dimension, surface roughness and mean particle diameter. Spectroreflectometry
showed the presence of an increase in optical absorbance attributed to plasmon resonance absorption of
the silver clusters. The photocatalytic properties of the surface modified materials were investigated through
photodegradation of Methyl Orange. The silver deposition conditions were optimized for maximum photocatalytic
efficiency and crucial parameters such as dipping period, UV irradiation time, and concentration
of the dipping solution were determined. The optimum silver nitrate concentration of the dipping solution
was found to be 10-3 M. This silver doped photocatalyst decomposes the azo-dye pollutant 3-times faster
than the un-doped Degussa P25 TiO2 film. A concentration increase results in a decrease of the films photocatalytic
performance. Strength and reproducibility tests proved that the photocatalytic activity of the silver
doped titania was perfectly reproducible
Bacteriome and Archaeome: The Core Family Under the Microbiomic Roof
The concept of “bacteriome” was recast to apply to microbiomics in the late 2000s as the major (in cell population and gene context) but residual part of individual microbiomes, once mycobiome and virome were detached. Following the genomic aspect of the microbiome of the era, the bacteriome abided to the three-domain concept, thus inaugurating the archaeome as well. Both prokaryotic biomes are characterized by diverse and massive horizontal gene transfer. The sum of antagonistic and cooperative interactions among the different participant prokaryota and their respective alterations over time, either spontaneously or due to a multitude of effectors, defines their attitude toward their surroundings, environmental, industrial, or health-associated (medicinal, veterinary, and phytopathological) contexts. Diverse in functional and spatiotemporal terms, the infinite bacteriomes are focal for process-based microbiomic studies, contrary to conventional, cell-based bacteriology, revealing novel traits as the development of multicellular, possibly chimeric prokaryota, as insinuated by multispecies biofilms. They are thus bound to attract major research effort and resources in near future. © 2020 Elsevier Inc. All rights reserved
The design and photoreaction kinetic modeling of a gas-phase titania foam packed bed reactor
The design and testing as well as theoretical and experimental study involving kinetic modeling and photooxidation reactions of a gas-phase photocatalytic packed bed reactor (PBR) based on a porous titania foam is reported. The photoreactor was designed to incorporate a nanoporous titania foam photocatalyst for volatile organic compound (VOC) remediation in the gas-phase. Theoretical and experimental studies based on the photodegradation of model volatile organic compounds (VOCs), have been carried out and results show that 90% degradation can be achieved in the photoreactor which has been designed at low cost and to provide increased efficiency at elevated pollutant feed. The reactor represents an inexpensive design and can be applied to the remediation of various pollutants of biological, organic or inorganic origin. In addition, the reactor can accommodate the photocatalyst in the form of a thin film and porous foams. © 2007 Elsevier B.V. All rights reserved
Cluster of Fusarium verticillioides bloodstream infections among immunocompetent patients in an internal medicine department after reconstruction works in Larissa, Central Greece
Background: Fusarium spp. can cause disseminated infections, particularly in immunocompromised patients. Fusarium verticillioides is a human pathogen, and sporadic cases of fusariosis have been reported. Aim: To report a nosocomial cluster of F.verticillioides bloodstream infections among seven immunocompetent inpatients following reconstruction works. Methods: Identification was performed using macroscopic and microscopic morphology, and molecular assays (sequencing the nuclear ribosomal internal transcribed spacer region and translation elongation factor-1α gene). Susceptibility testing was performed in accordance with the guidelines of the Clinical and Laboratory Standards Institute. Environmental surveillance specimens were taken and cultured on Sabouraud dextrose agar plates. Findings: In total, 16 blood cultures obtained from the seven patients were positive for F.verticillioides. All surveillance cultures were negative. Conclusions: In order to prevent fungaemia, it is important to implement effective infection control measures, before, during and after demolition and construction activities in healthcare settings. © 2014 The Healthcare Infection Society
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