Scott A Wade

Bio: Scott A Wade is an academic researcher from Swinburne University of Technology. The author has contributed to research in topics: Fiber Bragg grating & Optical fiber. The author has an hindex of 28, co-authored 153 publications receiving 3109 citations. Previous affiliations of Scott A Wade include Centre national de la recherche scientifique & Victoria University, Australia.

Fluorescence intensity ratio technique for optical fiber point temperature sensing

Abstract: The fluorescence intensity ratio technique for optical fiber-based point temperature sensing is reviewed, including the materials suitable for this technique. The temperature dependence of the fluorescence intensity ratio has been studied using thermally coupled energy levels in seven different rare earth ions doped into a variety of glasses and crystals. Sensor prototypes developed using Pr3+:ZBLANP, Nd3+-doped silica fiber and Yb3+-doped silica fiber as the sensing material have been used to measure temperatures covering the range of approximately −50 to 600 °C with a resolution of the order of 1 °C.

Comparison of fluorescence-based temperature sensor schemes: Theoretical analysis and experimental validation

Abstract: The performance of the two most promising fluorescence-based temperature sensing techniques, namely the fluorescence intensity ratio (FIR) and fluorescence lifetime (FL) schemes, have been compared. Theoretical calibration graphs for the two methods illustrate the useful monotonic change of the response with temperature variation. Comparison of the responses and the sensitivities of the two schemes show that at very low temperatures the FIR method exhibits a significant variation with temperature, while the response of the FL method becomes constant with its sensitivity approaching zero. With increasing temperature, the FIR and the FL methods (with short relaxation times and shorter intrinsic lifetimes of the upper energy levels) share a similar sensitivity over a wide temperature range. The presence of a long relaxation time or a longer intrinsic lifetime of the upper level in the use of the FL method gives a less satisfactory response. Experimental data obtained for a range of dopant ions in various hos...

Improved methods for fluorescence background subtraction from Raman spectra

Abstract: Raman spectroscopy has attracted interest as a non-invasive optical technique to study the composition and structure of a wide range of materials at the microscopic level. The intrinsic fluorescence background can be orders of magnitude stronger than the Raman scattering, and so, background removal is one of the foremost challenges for quantitative analysis of Raman spectra in many samples. A range of methods anchored in instrumental and computational programming approaches have been proposed for removing fluorescence background signals. An enhanced adaptive weighting scheme for automated fluorescence removal is reported, applicable to both polynomial fitting and penalized least squares approaches. Analysis of the background fitting results for ensembles of simulated spectra suggests that the method is robust and reliable and can significantly improve the background fit over the range of signal, shot noise and background parameters tested, while reducing the subjective nature of the process. The method was also illustrated by application to experimental data generated from aqueous solutions of bulk protein fibrinogen mixed with dextran. Copyright © 2013 John Wiley & Sons, Ltd.

The effect of size on the quantitative estimation of defect depth in steel structures using lock-in thermography

Abstract: An investigation into the effect of size on the quantitative estimation of defect depth in a steel specimen has been undertaken using lock-in thermography. Phase contrast measurements over circular defects of varying diameter and depth are presented for a range of excitation frequencies. It was found that the diameter of a defect had an appreciable effect on the observed phase angle which consequently has significant implications with regard to estimating defect depth. Phase contrast measurements for a range of defects in a 10mm steel specimen indicate that an excitation frequency of 0.02Hz is the optimal frequency for defect detection. Results obtained with an excitation frequency of 0.02Hz are used to discuss the limitations of determining the size and depth of defects. A finite element analysis was found to have good correlation with experimental data and thus demonstrates potential in providing improved estimates of defect depth.

Kirk-Othmer Encyclopedia of Chemical Technology数据库介绍及实例

Abstract: 介绍了Kirk—Othmer Encyclopedia of Chemical Technology（化工技术百科全书）（第五版）电子图书网络版数据库，并对该数据库使用方法和检索途径作出了说明，且结合实例简单地介绍了该数据库的检索方法。

Luminescent probes and sensors for temperature.

Abstract: Temperature (T) is probably the most fundamental parameter in all kinds of science. Respective sensors are widely used in daily life. Besides conventional thermometers, optical sensors are considered to be attractive alternatives for sensing and on-line monitoring of T. This Review article focuses on all kinds of luminescent probes and sensors for measurement of T, and summarizes the recent progress in their design and application formats. The introduction covers the importance of optical probes for T, the origin of their T-dependent spectra, and the various detection modes. This is followed by a survey on (a) molecular probes, (b) nanomaterials, and (c) bulk materials for sensing T. This section will be completed by a discussion of (d) polymeric matrices for immobilizing T-sensitive probes and (e) an overview of the various application formats of T-sensors. The review ends with a discussion on the prospects, challenges, and new directions in the design of optical T-sensitive probes and sensors.

Temperature sensing using fluorescent nanothermometers

Abstract: Acquiring the temperature of a single living cell is not a trivial task. In this paper, we devise a novel nanothermometer, capable of accurately determining the temperature of solutions as well as biological systems such as HeLa cancer cells. The nanothermometer is based on the temperature-sensitive fluorescence of NaYF4:Er3+,Yb3+ nanoparticles, where the intensity ratio of the green fluorescence bands of the Er3+ dopant ions (2H11/2 → 4I15/2 and 4S3/2 → 4I15/2) changes with temperature. The nanothermometers were first used to obtain thermal profiles created when heating a colloidal solution of NaYF4:Er3+,Yb3+ nanoparticles in water using a pump−probe experiment. Following incubation of the nanoparticles with HeLa cervical cancer cells and their subsequent uptake, the fluorescent nanothermometers measured the internal temperature of the living cell from 25 °C to its thermally induced death at 45 °C.

Fluorescence intensity ratio technique for optical fiber point temperature sensing

Abstract: The fluorescence intensity ratio technique for optical fiber-based point temperature sensing is reviewed, including the materials suitable for this technique. The temperature dependence of the fluorescence intensity ratio has been studied using thermally coupled energy levels in seven different rare earth ions doped into a variety of glasses and crystals. Sensor prototypes developed using Pr3+:ZBLANP, Nd3+-doped silica fiber and Yb3+-doped silica fiber as the sensing material have been used to measure temperatures covering the range of approximately −50 to 600 °C with a resolution of the order of 1 °C.