Electrostatic Field Influence on Luminescence Features of Cadmium Sulphide Quantum Dots in Silica Matrix
Publication date: 2017 Source:Physics Procedia, Volume 86 Author(s): S.S. Voznesenskiy, A.A. Sergeev, I.V. Postnova, Y.A. Shchipunov The effect of electrostatic field on optical properties of silicate nanocomposite with cadmium sulfide quantum dots was investigated. It was found that the electrostatic field causes quantum dot orientation along the field force lines leading to changes in the polarized components of the luminescence spectrum. The influence of field force line direction on photoinduced absorption characteristics arised from λ = 405.9nm laser radiation exposure to nanocomposite was shown. (Source: Physics Procedia)
Source: Physics Procedia - February 20, 2017 Category: Physics Source Type: research
Modification of Optical Properties of CdS-silicate Nanocomposites by Thermal Annealing
Publication date: 2017 Source:Physics Procedia, Volume 86 Author(s): A.A. Sergeev, S.S. Voznesenskiy, A.N. Galkina, I.V. Postnova Temperature influence on optical and structural properties of nanocomposite structures based on cadmium sulfide quantum dots in silicate matrix was investigated. The mechanism of occurrence of reversible laser-induced absorption is proposed. It was found that annealing of nanocomposite up to 120°C leads to substantial change of its absorption and luminescence spectra caused by transformation of quantum dot crystal lattice from amorphous to sphalerite. The nanocomposite with the sphalerite...
Source: Physics Procedia - February 20, 2017 Category: Physics Source Type: research
Single-shot Laser-assisted Nanofabrication of Plasmonic Nanorings
Publication date: 2017 Source:Physics Procedia, Volume 86 Author(s): A.V. Nepomnyashchii, A.A. Kuchmizhak, S.O. Gurbatov, O.B. Vitrik, Yu.N. Kulchin Simple high-performing two-step technique for fabrication different functional plasmonic nanostructures including nanorods, separated and crossed nanorings, as well as more complex hybrid structures on both glass and silicon substrates was proposed. In this technique the noble metal film covering bulk glass or silicon substrates is irradiated by single tightly focused nanosecond laser pulse followed by slow polishing of the fabricated nanostructures by accelerated argon...
Source: Physics Procedia - February 20, 2017 Category: Physics Source Type: research
An Automated Algorithm for Measurement of Surgical Tip Excursion in Ultrasonic Vibration Using the Spatial 2-Dimensional Fourier Transform in an Optical Image
We present data that shows an error of about 1% between manual and automated methods, when measurements are in the range of 300 microns and about 20% when the measurements are in the range of 30 microns. (Source: Physics Procedia)
Source: Physics Procedia - December 27, 2016 Category: Physics Source Type: research
Design of HIFU Transducers to Generate Specific Nonlinear Ultrasound Fields
Publication date: 2016 Source:Physics Procedia, Volume 87 Author(s): Vera A. Khokhlova, Petr V. Yuldashev, Pavel B. Rosnitskiy, Adam D. Maxwell, Wayne Kreider, Michael R. Bailey, Oleg A. Sapozhnikov Various clinical applications of high intensity focused ultrasound (HIFU) have different requirements on the pressure level and degree of nonlinear waveform distortion at the focus. Applications that utilize nonlinear waves with developed shocks are of growing interest, for example, for mechanical disintegration as well as for accelerated thermal ablation oftissue. In this work, an inverse problem of determining transd...
Source: Physics Procedia - December 27, 2016 Category: Physics Source Type: research
Nonlinear Characterization of Half and Full Wavelength Power Ultrasonic Devices
This study tries to provide an understanding of the effects that geometry and material choices may have on the nonlinear behavior of a tuned device. (Source: Physics Procedia)
Source: Physics Procedia - December 27, 2016 Category: Physics Source Type: research
Ultrasonically Assisted Cutting of Bio-tissues in Microtomy
Publication date: 2016 Source:Physics Procedia, Volume 87 Author(s): Dong Wang, Anish Roy, Vadim V. Silberschmidt Modern-day histology of bio-tissues for supporting stratified medicine diagnoses requires high-precision cutting to ensure high quality extremely thin specimens used in analysis. Additionally, the cutting quality is significantly affected by a wide variety of soft and hard tissues in the samples. This paper deals with development of a next generation of microtome employing introduction of controlled ultrasonic vibration to realise a hybrid cutting process of bio-tissues. The study is based on a combination...
Source: Physics Procedia - December 27, 2016 Category: Physics Source Type: research
Novel Round Energy Director for Use with Servo-driven Ultrasonic Welder
This article summarizes results of recent studies focused on evaluating performance of round energy director and investigating the main factors responsible for the joint quality. (Source: Physics Procedia)
Source: Physics Procedia - December 27, 2016 Category: Physics Source Type: research
Development of an Ultrasonic Resonator for Ballast Water Disinfection
Publication date: 2016 Source:Physics Procedia, Volume 87 Author(s): Hafiiz Osman, Fannon Lim, Margaret Lucas, Prakash Balasubramaniam Ultrasonic disinfection involves the application of low-frequency acoustic energy in a water body to induce cavitation. The implosion of cavitation bubbles generates high speed microjets >1 km/s, intense shock wave >1 GPa, localized hot spots >1000 K, and free-radicals, resulting in cell rupture and death of micro-organisms and pathogens. Treatment of marine ballast water using power ultrasonics is an energy-intensive process. Compared with other physical treatmen...
Source: Physics Procedia - December 27, 2016 Category: Physics Source Type: research
An Ultrasonic Caliper Device for Measuring Acoustic Nonlinearity
Publication date: 2016 Source:Physics Procedia, Volume 87 Author(s): Christopher Hunter, Oleg A. Sapozhnikov, Adam D. Maxwell, Vera A. Khokhlova, Yak-Nam Wang, Brian MacConaghy, Wayne Kreider In medical and industrial ultrasound, it is often necessary to measure the acoustic properties of a material. A specific medical application requires measurements of sound speed, attenuation, and nonlinearity to characterize livers being evaluated for transplantation. For this application, a transmission-mode caliper device is proposed in which both transmit and receive transducers are directly coupled to a test sample, the p...
Source: Physics Procedia - December 27, 2016 Category: Physics Source Type: research
Performance of PZT8 Versus PZT4 Piezoceramic Materials in Ultrasonic Transducers
Publication date: 2016 Source:Physics Procedia, Volume 87 Author(s): Dominick A. DeAngelis, Gary W. Schulze PZT8 and PZT4 are the common “hard” piezoceramic materials used in power ultrasonic transducers (e.g., welding, cutting, sonar, etc.). PZT8 is perceived as the better choice for resonant devices, primarily due to its higher mechanical quality factor Q m . PZT8 is also considered a “harder” material compared to PZT4, since it has better stability at higher preloads and drive levels. Many transducer designers never consider PZT4 for their applications, even though it has clear advantages such as higher outp...
Source: Physics Procedia - December 27, 2016 Category: Physics Source Type: research
Unusual Applications of Ultrasound in Industry
Publication date: 2016 Source:Physics Procedia, Volume 87 Author(s): George Keilman The application of physical acoustics in industry has been accelerated by increased understanding of the physics of industrial processes, coupled with rapid advancements in transducers, microelectronics, data acquisition, signal processing, and related software fields. This has led to some unusual applications of ultrasound to improve industrial processes. (Source: Physics Procedia)
Source: Physics Procedia - December 27, 2016 Category: Physics Source Type: research
An Ultrasonic Compactor for Oil and Gas Exploration
Publication date: 2016 Source:Physics Procedia, Volume 87 Author(s): Andrew Feeney, Sakalima Sikaneta, Patrick Harkness, Margaret Lucas The Badger Explorer is a rig-less oil and gas exploration tool which drills into the subsea environment to collect geological data. Drill spoil is transported from the front end of the system to the rear, where the material is compacted. Motivated by the need to develop a highly efficient compaction system, an ultrasonic compactor for application with granular geological materials encountered in subsea environments is designed and fabricated as part of this study. The finite element ...
Source: Physics Procedia - December 27, 2016 Category: Physics Source Type: research
Ultrasonically-assisted Polymer Molding: An Evaluation
Publication date: 2016 Source:Physics Procedia, Volume 87 Author(s): Matthew Moles, Anish Roy, Vadim Silberschmidt Energy reduction in extrusion and injection molding processes can be achieved by the introduction of ultrasonic energy. Polymer flow can be enhanced on application of ultrasonic vibration, which can reduce the thermal and pressure input requirements to produce the same molding; higher productivity may also be achieved. In this paper, a design of an ultrasound–assisted injection mold machine is explored. An extrusion-die design was augmented with a commercial 1.5kW ultrasonic transducer and sonotrode des...
Source: Physics Procedia - December 27, 2016 Category: Physics Source Type: research
Airborne Power Ultrasonic Technologies for Intensification of Food and Environmental Processes
Publication date: 2016 Source:Physics Procedia, Volume 87 Author(s): Enrique Riera, Víctor M. Acosta, José Bon, Manuel Aleixandre, Alfonso Blanco, Roque R. Andrés, Andrea Cardoni, Ignacio Martinez, Luís E. Herranz, Rosario Delgado, Juan A. Gallego-Juárez Airborne power ultrasound is a green technology with a great potential for food and environmental applications, among others. This technology aims at producing permanent changes in objects and substances by means of the propagation of high-intensity waves through air and multiphase media. Specifically, the nonlinear effects produced in such media are resp...
Source: Physics Procedia - December 27, 2016 Category: Physics Source Type: research
