Search results for " Fiber"
showing 10 items of 1776 documents
Spectroscopic Properties of Holmium-Aluminum- Germanium Co-doped Silica Fiber
2020
We report the basic spectroscopic properties of a home-made holmium-aluminum-germanium co-doped silica fiber, designed for laser applications. We present the ground-state and excitedstate absorption spectra of the fiber along with the upconversion emission spectrum under laser action, which served for making an energy levels’ diagram of Ho3+ ion. We discuss the ways to assess the kinetics of Ho3+ 2-μm fluorescence, focusing on measuring fluorescence lifetime from 5I7 level and nonradiative decay time from 5I6 level. The simple analytical formulae, applicable for fitting of the fluorescence decay curve, are derived, which can be useful for precise modeling of holmiumdoped fiber lasers. PID20…
Experimental Analysis of the Thermal Performance of Wood Fiber Insulating Panels
2023
During the last decades, attention to energy and environmental problems has significantly grown, along with the development of international and national policies addressing sustainability issues. In the construction sector, one of the most widespread energy efficiency strategies consists of thermal insulation of buildings thanks to external insulating panels. Among these, wood fiber is an insulating material characterized by a natural, eco-sustainable and biodegradable structure, coming from the recycling of waste wood from sawmills. The present study aimed to characterize small test building insulated with wood fiber panels from the thermal point of view, comparing the results with those …
Some recent results on the compressive and flexural behaviour of composite members
2005
Experiemntal results from compression and flexural tests on steel tubulare columns having circular or rectangular transverse cross-section and infilled with plain or fiber reinforced concrete (FRC) are analysez. for composite members differenti lengths and different dimensions of transverse cross-section were considered in order to assess the influence on behavior in flexure and in compression.The fiber investigated with different percentage were syntetic, carbon and deformed steel fibers. The constituent materials were characterised through compressive and split tests on conconcrete cylinders. Load.shortning and load-delection curves were determined including the sotnening response. Simpli…
Cladding-Pumped Er/Yb-Co-Doped Fiber Amplifier for Multi-Channel Operation
2022
The Institute of Solid State Physics, University of Latvia, as a Center of Excellence, has received funding from the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART2. We express our gratitude to rer. nat. Nicoletta Haarlammert from Fraunhofer Institute for Applied Optics and Precision Engineering IOF for the refractive index measurements of ytterbium/erbium-co-doped fibers. This work is supported by the European Regional Development Fund project No. 1.1.1.1/18/A/068.
Biological and antibacterial properties of a new silver fiber post : in vitro evaluation
2016
Background The incorporation of nano silver particles (AgNPs) to improve antibacterial properties of dental materials has become increasingly common. The aim of the present study was to compare the antibacterial activity and cytotoxicity effects of different fiber posts: glass fiber post, quartz fiber post, nano fiber post and silver fiber post. Material and methods The antibacterial activity against S. mutans, S. salivarius and S. sanguis was evaluated by using the agar disc diffusion test (ADT). Four wells of 3x2 mm (one for each material) were made with a punch by removing the agar and filled with the materials to be evaluated. The size of the inhibition zone was calculated. An extract w…
Fracture strenght and ribbond fibers: In vitro analysis of mod restorations
2023
Ribbond fibers are supposed to be a reinforcing material in restoration of compromised teeth. This study aims to compare MOD restorations with and without Ribbond Fiber in terms of fracture strength under axial loading; to identify the minimum depth of MO
Pullout Force and Inlet Oscillation in Telescopic Carbon Nanotubes: A Quantum Study
2021
The noncovalent interaction energy as a function of the core extension in double-walled carbon nanotubes (DWCNT) was accurately calculated in the frame of density functional theory, considering dis...
Glaucomatous Maculopathy: Thickness Differences on Inner and Outer Macular Layers between Ocular Hypertension and Early Primary Open-Angle Glaucoma U…
2020
The purpose of this study was to compare the thickness of all inner and outer macular layers between ocular hypertension (OHT) and early primary open-angle glaucoma (POAG) using spectral domain optical coherence tomography (SD-OCT) 8 × 8 posterior pole algorithm (8 × 8 PPA). Fifty-seven eyes of 57 OHT individuals and fifty-seven eyes of 57 early POAG patients were included. The thickness of macular retinal nerve fiber layer (mRNFL), ganglion cell layer (GCL), inner plexiform layer (IPL), inner nuclear layer (INL), outer plexiform and nuclear layer, photoreceptor layer (PRL) and retinal pigment epithelium were obtained in 64 cells for each macular layer and mean thickness of superior and inf…
Single hollow fiber SLM extraction of polyamines followed by tosyl chloride derivatization and HPLC determination
2007
Determination of polyamines in biological fluids possesses medical diagnostic relevance. Despite the vast panel of analytical methods developed for polyamines they are not applied in routine clinical usage, mainly due to the time and labor consuming sample preparation step and complicated derivatization procedures. Thus, new simpler methods are needed. This paper describes a single hollow fiber SLM extraction method of polyamines followed by simple pre-column derivatization with tosyl chloride and HPLC-UV analysis. The influence of different parameters such as the extraction time, organic phase composition, acceptor pH, donor pH, acceptor volume, donor volume and stirring speed on the trans…
Influence of temperature on mass transfer in an incomplete trapping single hollow fibre supported liquid membrane extraction of triazole fungicides.
2008
The influence of temperature in a single hollow fibre supported liquid membrane extraction of triazole fungicides with a stagnant acceptor phase was investigated. The mass transfer parameters such as diffusion coefficient, flux and apparent viscosity were determined at temperature ranging from 278 K to 313 K. Increase in temperature led to an increase in diffusion coefficient and flux. The apparent viscosity also decreased with an increase in temperature. The degree of trapping in the acceptor phase influenced the mass transfer at higher temperature. At lower temperature, the transport of analytes from the donor solution through the donor-membrane interface and through the membrane mainly a…