Analyte sensitivity for gas sensors based on semiconducting metal oxides should be highly dependent on the film thickness, particularly when that thickness is on the order of the Debye length. This thickness dependence has previously been demonstrated for SnO₂ and inferred for TiO₂. In this paper, TiO₂ thin films have been prepared by Atomic Layer Deposition (ALD) using titanium isopropoxide and water as precursors. The deposition process was performed on standard alumina gas sensor platforms and microscope slides (for analysis purposes), at a temperature of 200 °C. The TiO₂ films were exposed to different concentrations of CO, CH₄, NO₂, NH₃ and SO₂ to evaluate their gas sensitivities. These experiments showed that the TiO₂ film thickness played a dominant role within the conduction mechanism and the pattern of response for the electrical resistance towards CH₄ and NH₃ exposure indicated typical -type semiconducting behavior. The effect of relative humidity on the gas sensitivity has also been demonstrated.
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http://dx.doi.org/10.3390/s18030735 | DOI Listing |
Cont Lens Anterior Eye
January 2025
Department of Ophthalmology, Aotearoa New Zealand National Eye Centre, The University of Auckland, Auckland, New Zealand. Electronic address:
Purpose: To investigate the prognostic ability of blink rate and the proportion of incomplete blinking to predict dry eye disease diagnosis, as defined by the TFOS DEWS II criteria.
Methods: A total of 453 community residents (282 females, 171 males; mean ± SD age, 37 ± 19 years) were recruited in an investigator-masked, prospective registry-based, cross-sectional, prognostic study. Dry eye symptomology, tear film quality, and ocular surface characteristics were assessed in a single clinical session, and blink parameters evaluated by an independent masked observer.
J Fr Ophtalmol
January 2025
Department of Ophthalmology, Cochin Hospital, Université Paris-Cité, Assistance Publique-Hôpitaux de Paris, Paris, France; Inserm, Centre de Recherche des Cordeliers, Unit 1138 team 17, Paris, France.
Objective: To compare the corneal topographic parameters and ocular surface parameters of ocular rosacea (OR) patients across skin subtypes of the disease and healthy controls.
Methods: This prospective study included 180 eyes of 90 OR patients and 60 eyes of 30 healthy controls. Among the OR patients, 30 had phymatous (60 eyes), 30 had erythematotelangiectatic (60 eyes) and 30 had papulopustular skin types (60 eyes).
Foods
January 2025
Center of Excellence Polymer Processing, Faculty of Engineering, Dunarea de Jos University of Galați, Domnească Street, No. 111, 800201 Galați, Romania.
Electrospinning is a versatile technique for obtaining nano/micro fibers which are able to significantly change the active properties of composite materials and bring in new dimensions to agri-food applications. Composite bio-based packaging materials obtained from whey proteins, functionalized with thyme essential oil (TEO) and reinforced by electrospun polylactic acid (PLA) fibers, represent a promising solution for developing new active food packaging using environmentally friendly materials. The aim of this study is to obtain and characterize one-side-active composite films covered with a PLA fiber mat: (i) WF/G1, WF/G2, and WF/G3 resulting from electrospinning with one needle at different electrospinning times of 90, 150, and 210 min, respectively, and (ii) WF/G4 obtained with two face-to-face needles after 210 min of electrospinning.
View Article and Find Full Text PDFMaterials (Basel)
January 2025
College of Physics and Electronic Information, Shandong Key Laboratory of Biophysics, Dezhou University, Dezhou 253023, China.
Electrochromic capacitors, which are capable of altering their appearances in line with their charged states, are drawing substantial attention from both academia and industry. Tungsten oxide is usually used as an electrochromic layer material for electrochromic devices, or as an active material for high-performance capacitor electrodes. Despite this, acceptable visual aesthetics in electrochromic capacitors have almost never been achieved using tungsten oxide, because, in its pure form, this compound only displays a onefold color modulation from transparent to blue.
View Article and Find Full Text PDFMaterials (Basel)
December 2024
School of Materials Science and Engineering, Kumoh National Institute of Technology, Gumi 39177, Republic of Korea.
Phase-change random access memory (PcRAM) faces significant challenges due to the inherent instability of amorphous GeSbTe (GST). While doping has emerged as an effective method for amorphous stabilization, understanding the precise mechanisms of structural modification and their impact on material stability remains a critical challenge. This study provides a comprehensive investigation of elastic strain and stress in crystalline lattices induced by various dopants (C, N, and Al) through systematic measurements of film thickness changes during crystallization.
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