Practical applications in UV Raman line imaging of water vapor

1994 ◽  
Author(s):  
Peter A. DeBarber ◽  
Cecil F. Hess ◽  
Robert W. Pitz ◽  
Sastri P. Nandula ◽  
Thomas M. Brown III ◽  
...  
Keyword(s):  
Water Vapor ◽  
Raman Line ◽  
Practical Applications ◽  
Uv Raman ◽  
Line Imaging

Investigation of CO2 sorption in molten polymers at high pressures using Raman line imaging

Polymer ◽  
2013 ◽  
Vol 54 (2) ◽  
pp. 812-818 ◽  
Author(s):  
Oliver Sven Knauer ◽  
Maria Giovanna Pastore Carbone ◽  
Andreas Braeuer ◽  
Ernesto Di Maio ◽  
Alfred Leipertz
Keyword(s):  
Raman Line ◽  
High Pressures ◽  
Co2 Sorption ◽  
Molten Polymers ◽  
Line Imaging

Hyperspectral Raman Line Imaging of Syndiotactic Polystyrene Crystallinity

1998 ◽  
Vol 52 (10) ◽  
pp. 1264-1268 ◽  
Author(s):  
Shuliang L. Zhang ◽  
Jerilyn A. Pezzuti ◽  
Michael D. Morris ◽  
Aruna Appadwedula ◽  
Chang-Meng Hsiung ◽  
...  
Keyword(s):  
Factor Analysis ◽  
Raman Line ◽  
The Other ◽  
Moderate Intensity ◽  
Syndiotactic Polystyrene ◽  
Raman Intensity ◽  
Structure Information ◽  
Intensity Image ◽  
Line Imaging ◽  
Noise Factors

The crystallinity of syndiotactic polystyrene (sPS) is studied by hyperspectral Raman line imaging. Images of a 140 × 1200 μm region of an sPS test piece containing 39 200 pixels/image were generated from spectra taken over the wavenumber interval between 300 and 875 cm−1. The spectral region includes the moderate-intensity crystallinity-sensitive bands in the 770 800 cm−1 region, as well as other useful but weaker marker bands. Factor analysis was used to extract structure information from the set of spectra. Four non-noise factors were extracted; two were assigned to crystalline and amorphous sPS and the other two to background. Score images of the crystalline and amorphous sPS factors were used to visualize distribution of those species. The results were compared to the integrated Raman intensity image for the 773 cm−1 band of crystalline sPS.

Remote detection of liquids by Raman line imaging

2008 ◽  
Author(s):  
Chris R. Howle ◽  
Christopher D. Dyer ◽  
Kurt J. Baldwin ◽  
Richard J. White
Keyword(s):  
Raman Line ◽  
Remote Detection ◽  
Line Imaging

Hyperspectral Raman Microscopic Imaging Using Powell Lens Line Illumination

1998 ◽  
Vol 52 (9) ◽  
pp. 1145-1147 ◽  
Author(s):  
Kenneth A. Christensen ◽  
Michael D. Morris
Keyword(s):  
Raman Line ◽  
Signal To Noise Ratio ◽  
Numerical Aperture ◽  
Acquisition Time ◽  
Charge Coupled Device ◽  
Illumination System ◽  
Image Acquisition Time ◽  
Intensified Charge Coupled Device ◽  
Line Imaging

The design and characterization of a simple and robust hyperspectral Raman line imaging illumination system with the use of a Powell lens is reported. The generated line uniformity is ±5% of total intensity with a laser power density of 12 mW/μm2 at the sample with a 50×/0.8 NA (numerical aperture) objective. Similar results were obtained by using other objectives. Linewidths remained near the diffraction limit for all objectives tested. Significant decreases in image acquisition time are also reported with the use of a Powell lens-illuminated hyperspectral Raman line imaging microscope equipped with an intensified charge-coupled device (CCD) detector. Hyperspectral images (100 × 350 pixels) were acquired in as little as 8 with a corresponding signal-to-noise ratio of 24.

scholarly journals The Initial Oxidation of HfNiSn Half-Heusler Alloy by Oxygen and Water Vapor

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3942
Author(s):  
Oshrat Appel ◽  
Shai Cohen ◽  
Ofer Beeri ◽  
Yaniv Gelbstein ◽  
Shimon Zalkind
Keyword(s):  
Water Vapor ◽  
Photoelectron Spectroscopy ◽  
Elevated Temperatures ◽  
Surface Composition ◽  
Waste Heat ◽  
Water Vapor Pressure ◽  
Formation Enthalpy ◽  
Environmental Stability ◽  
Initial Oxidation ◽  
Practical Applications

The MNiSn (M = Ti, Zr, Hf) n-type semiconductor half-Heusler alloys are leading candidates for the use as highly efficient waste heat recovery devices at elevated temperatures. For practical applications, it is crucial to consider also the environmental stability of the alloys at working conditions, and therefore it is required to characterize and understand their oxidation behavior. This work is focused on studying the surface composition and the initial oxidation of HfNiSn alloy by oxygen and water vapor at room temperature and at 1000 K by utilizing X-ray photoelectron spectroscopy. During heating in vacuum, Sn segregated to the surface, creating a sub-nanometer overlayer. Exposing the surface to both oxygen and water vapor resulted mainly in Hf oxidation to HfO2 and only minor oxidation of Sn, in accordance with the oxide formation enthalpy of the components. The alloy was more susceptible to oxidation by water vapor compared to oxygen. Long exposure of HfNiSn and ZrNiSn samples to moderate water vapor pressure and temperature, during system bakeout, resulted also in a formation of a thin SnO2 overlayer. Some comparison to the oxidation of TiNiSn and ZrNiSn, previously reported, is given.

A UV Raman Lidar for monitoring water vapor

2001 ◽  
Author(s):  
Savyasachee Mathur ◽  
Matthew K. Nam ◽  
Coorg R. Prasad
Keyword(s):  
Water Vapor ◽  
Raman Lidar ◽  
Uv Raman

Hyperspectral Raman Line Imaging of an Aluminosilicate Glass

1998 ◽  
Vol 52 (1) ◽  
pp. 64-69 ◽  
Author(s):  
Nancy L. Jestel ◽  
Jeremy M. Shaver ◽  
Michael D. Morris
Keyword(s):  
Factor Analysis ◽  
Raman Line ◽  
The Other ◽  
Aluminosilicate Glass ◽  
Nonbridging Oxygen ◽  
Silica Network ◽  
Data Set ◽  
Dental Restorations ◽  
Line Imaging ◽  
Significant Factors

An aluminosilicate glass, which is a model for glass formulations used as dental restorations, was examined by hyperspectral Raman line imaging. The data set consisted of more than 30000 spectra, which were analyzed by using factor analysis. Nine score images were constructed from the nine significant factors identified. Three factors represent convolutions of noise, background, and offset. The other six factors represent Raman spectra of different bonding environments of the silicate tetrahedron. Three of those factors contain narrow Raman features. These are associated with a fully polymerized silica network, with a silicate tetrahedron with one nonbridging oxygen, and with an alumina-related inclusion or a silicate tetrahedron with two nonbridging oxygens. The last three significant factors contain broad Raman bands representing continua of slightly different bonding environments of silicate tetrahedra with 0–4 nonbridging oxygens. The score images reveal that the glass, although not homogeneous, has few regions with discrete heterogeneities. The different bonding networks commingle and could be interconnected.

New Design for a Differentially Pumped Hydration Chamber for a Siemens IA

1971 ◽  
Vol 29 ◽  
pp. 44-45
Author(s):  
R. C. Moretz ◽  
G. G. Hausner ◽  
D. F. Parsons
Keyword(s):  
Electron Microscopy ◽  
Water Vapor ◽  
Electron Diffraction ◽  
Water Vapor Pressure ◽  
Biological Materials ◽  
Thin Membrane ◽  
Reliable System ◽  
System A ◽  
Water Films ◽  
Aperture Opening

Electron microscopy and diffraction of biological materials in the hydrated state requires the construction of a chamber in which the water vapor pressure can be maintained at saturation for a given specimen temperature, while minimally affecting the normal vacuum of the remainder of the microscope column. Initial studies with chambers closed by thin membrane windows showed that at the film thicknesses required for electron diffraction at 100 KV the window failure rate was too high to give a reliable system. A single stage, differentially pumped specimen hydration chamber was constructed, consisting of two apertures (70-100μ), which eliminated the necessity of thin membrane windows. This system was used to obtain electron diffraction and electron microscopy of water droplets and thin water films. However, a period of dehydration occurred during initial pumping of the microscope column. Although rehydration occurred within five minutes, biological materials were irreversibly damaged. Another limitation of this system was that the specimen grid was clamped between the apertures, thus limiting the yield of view to the aperture opening.

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