Application de techniques de multiplexing holographique à l'interférométrie : I. Holographie multiplex à codage du faisceau objet

1976 ◽  
Vol 54 (20) ◽  
pp. 2060-2066
Author(s):  
R. A. Lessard ◽  
M. Pagé ◽  
A. Boivin
Keyword(s):  
Fourier Transform ◽  
Measurement Technique ◽  
Holographic Interferometry ◽  
Object Beam ◽  
Qualitative Observation ◽  
Selection Of

Holographic interferometry is a measurement technique through which displacements or deformations of objects may also be made evident to qualitative observation. For this type of interferogram the signals recorded usually arise from a well-defined portion of the phenomenon under study. This selection of the information to be recorded will therefore necessitate a preliminary knowledge of the course of the phenomenon. In multiplex holographic many signals are recorded over the same photographic medium so that, by proper coding of a sequence of signals, these can be made to interfere two at a time when reconstructed. When multiplexing is achieved by object beam coding, studies of possible applications have shown that the procedures of Fourier transform holography using a lens and orthoscopic pupil mask multiplexing may both serve to code optical informations from a phenomenon and provide, after decoding, an interferometric analysis of this same phenomenon.[Journal translation]

Analysis of Captan on Nitrile Glove Surfaces Using a Portable Attenuated Total Reflection Fourier Transform Infrared Spectrometer

2005 ◽  
Vol 59 (6) ◽  
pp. 724-731 ◽  
Author(s):  
R. N. Phalen ◽  
Shane S. Que Hee
Keyword(s):  
Fourier Transform ◽  
Fourier Transform Infrared ◽  
Total Reflection ◽  
Attenuated Total Reflection ◽  
Surface Films ◽  
Airflow Rate ◽  
Infrared Spectrometer ◽  
Ftir Spectrometer ◽  
Selection Of ◽  
Solvent Volume

This study developed a method to produce uniform captan surface films on a disposable nitrile glove for quantitation with a portable attenuated total reflection Fourier transform infrared (ATR-FTIR) spectrometer. A permeation test was performed using aqueous captan formulation. Uniform captan surface films were produced using solvent casting with 2-propanol and a 25 mm filter holder connected to a vacuum manifold to control solvent evaporation. The coefficient of variation of the reflectance at 1735 ± 5 cm−1 was minimized by selection of the optimum solvent volume, airflow rate, and evaporation time. At room temperature, the lower to upper quantifiable limits were 0.31–20.7 μg/cm2 ( r = 0.9967; p ≤ 0.05) for the outer glove surface and 0.55–17.5 μg/cm2 ( r = 0.9409; p ≤ 0.05) for the inner surface. Relative humidity and temperature did not affect the uncoated gloves at the wavelength of captan analysis. Glove screening using ATR-FTIR was necessary as a control for between-glove variation. Captan permeation, after 8 hours exposure to an aqueous concentration of 217 mg/mL of Captan 50-WP, was detected at 0.8 ± 0.3 μg/cm2 on the inner glove surface. ATR-FTIR can detect captan permeation and can determine the protectiveness of this glove in the field.

Fourier-Transform Infrared Spectroscopy of Environmentally Weathered Textile Fabrics for Enhanced Microplastic Identification

2021 ◽  
Author(s):  
Shreyas Patankar ◽  
Ekaterina Vassilenko ◽  
Mathew Watkins ◽  
Anna Posacka ◽  
Peter Ross
Keyword(s):  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Fourier Transform Infrared Spectroscopy ◽  
Infrared Spectra ◽  
Environmental Fate ◽  
Uv Light ◽  
Natural Fibers ◽  
Fourier Transform Infrared ◽  
Ambient Conditions ◽  
Selection Of

<p>Microplastic pollution in oceans is among the global environmental concerns of our time. Emerging research on ocean environments indicates that microfibers, such as those originating from textiles, are some of the most commonly occurring type of microplastic contaminants. While Fourier-transform infrared spectroscopy (FTIR) is commonly used to identify and characterize pollutant samples obtained from the environment, this identification is challenging because infrared spectra of materials can be modified by exposure to the ocean, air, UV light, and other ambient conditions, in a process referred to as “weathering”. We report preliminary efforts in improving FTIR characterization of microplastics by building a library of infrared spectra of common textile fibers weathered under a selection of ambient conditions. Consumer textile materials including polyester, nylon, cotton, and other, were exposed to a selection of ambient conditions: ocean, air, and wastewater treatment stages, in a controlled weathering experiment. Infrared spectra were monitored for up to 52 weeks, with the resulting data illuminating on the environmental fate and longevity of synthetic and natural fibers. Spectral changes caused by weathering were found to depend strongly on both the composition of the material and the specific ambient conditions. This library of weathered material spectra is useful not only in easier identification of environmental microfibers, but also in helping us estimate the duration and manner of weathering that a given environmental microfiber may have experienced.</p>

The Passing Behaviors of Vapor through Cloth

2006 ◽  
Vol 128 (8) ◽  
pp. 739-739
Author(s):  
Akira Narumi ◽  
Kenichi Uchida ◽  
Tadashi Konishi
Keyword(s):  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
Measurement Technique ◽  
Human Body ◽  
Holographic Interferometry ◽  
Liquid Surface ◽  
Scientific Research ◽  
Liquid Temperature ◽  
Small Space ◽  
Sweat Evaporation

There occurs heat and mass transfer through cloth in the very small space from skin to the outside of cloth due to the release of heat and sweat evaporation from human body. The new simultaneous 2-D measurement technique of temperature and concentration distributions that combines infrared absorbing method (IR) with holographic interferometry (HI) was applied to this space. Cotton (porosity Φ=0.586, thickness t=324μm) and nylon (Φ=0.578, t=347μm) were used for the typical hydrophilic and hydrophobic clothes, respectively. N-propanol was used for liquid. The distance from liquid surface to cloth was 5mm. Liquid temperature was 40°C. The superimposed images of HI and IR show clearly that more vapor passes through cloth in the case of cotton than in the case of nylon. This fact demonstrates that this new technique is very useful for measuring the passing behaviors of vapor through cloth. We appreciate that this research was partially supported by funds of Grant-in-Aid for Scientific Research in Japan.

Digital Recording and Numerical Reconstruction of Holograms: A New Optical Diagnostic for Combustion

2002 ◽  
Author(s):  
Xudong Xiao ◽  
Ishwar K. Puri
Keyword(s):  
Numerical Method ◽  
Measurement Technique ◽  
Holographic Interferometry ◽  
Fourier Optics ◽  
Chemical Processing ◽  
Digital Recording ◽  
Real Time Processing ◽  
Time Processing ◽  
Numerical Reconstruction ◽  
Optical Diagnostic

Digital holographic interferometry (DHI) is a relatively newer imaging and measurement technique that electronically records a hologram (e.g., on a CCD) and reconstructs it using a numerical method. Cumbersome chemical processing of the hologram is avoided in DHI, thereby providing greater flexibility, speed, and the potential for real time processing. In conventional holography fringes that are neither bright nor dark on a hologram cannot be accurately resolved. The DHI technique reported so far has not yet been used for combustion applications. Herein, we will evaluate its efficacy for making temperature measurements in flames and assess its applicability through a simulation. The double exposures associated with the holographic technique are each considered recorded by a hypothetical CCD sensor at separate times. We have applied the principles of Fourier optics to develop a numerical method for hologram reconstruction.

scholarly journals Application of particle image velocimetry to dusty plasma systems

2016 ◽  
Vol 82 (3) ◽  
Author(s):  
Jeremiah D. Williams
Keyword(s):  
Particle Image Velocimetry ◽  
Dusty Plasma ◽  
Measurement Technique ◽  
Diagnostic Tool ◽  
Particle Image ◽  
Thermal State ◽  
Diagnostic Technique ◽  
Future Directions ◽  
Image Velocimetry ◽  
Selection Of

Particle image velocimetry is a fluid measurement technique that has been used for more than 20 years to characterize the particle transport and thermal state of dusty plasma systems. This manuscript provides an overview of this diagnostic technique, highlighting the strengths and limitations that are associated with its use. Additionally, the variations of this technique that have been applied in the study of dusty plasma systems will be discussed, along with a small selection of measurements that can be made with the technique. Potential future directions for this diagnostic tool within the dusty plasma community will also be discussed.

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