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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Influence of operating parameters on aerosol characteristics of selected inductively coupled plasma optical emission spectrometry nebulizers

Wagner, Janet 12 1900 (has links)
No description available.
42

Fundamental studies of a graphite rod electrothermal vaporization device for sample introduction in atomic emission spectroscopy

Schmertmann, Susan Mace 08 1900 (has links)
No description available.
43

A novel sample introduction device for inductively coupled plasma-optical emission spectrometry

Faske, Arthur Joseph 12 1900 (has links)
No description available.
44

Studies of sample introduction for inductively coupled plasma emission spectrometry

Boorn, Andrew William 05 1900 (has links)
No description available.
45

Raman spectroscopic studies of (A) the Co-C bond in vitamin B## and model compounds, (B) inorganic matrices-encapsulated metallocomplexes, and (C) molecular hydrogen compounds

Chopra, Manu 05 1900 (has links)
No description available.
46

A study of sample introduction for inductively coupled plasma atomic emission spectrometry using volatile metal chelate complexes

Black, Marilyn Shull 12 1900 (has links)
No description available.
47

A multimodal spectrometer for Raman scattering and near-infrared absorption measurement

Wang, Wenbo 05 September 2012 (has links)
In food and pharmaceutical industries, the compositional complexity of raw materials and products promotes the use of multiple spectroscopic techniques. Availability of complementary methods, e.g., infrared absorption and Raman, is highly desirable. A multimodal Raman/NIR spectroscopic device was proposed. The device offered fast, non-destructive measurement, and remote sensing capability. A prototype was built. Spectral range covered 300-2600 cm-1 for Raman channel. Wavelength accuracy was better than 0.57 nm. Spectral resolution was better than 14.39 cm-1 (1 nm) for Raman (NIR) channel. Spectral response linearity was better than 0.998. Instrumental stability was better than 0.72% (0.39%) for Raman (NIR) channel. The device was applied to quantify ethanol aqueous solutions (2%-10% (v/v)). Quantitation results gave a root mean squared error of prediction (RMSEP) of 0.45% (v/v). Calibration using NIR absorbance spectra produced a RMSEP value of 0.49% (v/v). Raman technique offered the most succinct calibration model using peak height at 882.29 cm-1. Quantitation of ovalbumin (8%-16% (w/v)) in aqueous solutions and denatured states was also attempted. Stepwise multiple regression was performed using Raman peaks at 1243.35, 1448.68, 1662.66, and 1667.78 cm-1, which produced RMSEPs of 1.05 % (w/v) for ovalbumin solutions and 0.74 % (w/v) for ovalbumin gels. Conformational change of ovalbumin upon thermal denaturation was studied using the height and area ratios between peaks at 1243.35 and 1662.66 cm-1. Thermal denaturation of ovalbumin occurred at 70 °C and extensive formation of anti-parallel β-sheet structure was found at 90 °C. The unique capability of this multimodal device was proven by first performing data fusion of Raman and NIR spectra for quantitation. Using the same ethanol spectra set gave a more complicated model and a higher RMSEP of 0.73% (v/v). However, important variables in fused spectra corresponded well with the spectral signatures of ethanol and water. Two-dimensional correlation spectra were calculated using concentration as the external perturbation. The autopower spectra revealed features pertinent to those of the analytes. Heterospectral correlation analysis was carried out on Raman/NIR spectra of ethanol aqueous solution. Raman peaks at 882.29 and 1454.00 cm-1 agreed with the NIR absorption feature around 906.18 nm.
48

Preliminary investigation of radiation phenomena in high pressure air and argon cascade arcs

Dodson, Daniel Powell 12 1900 (has links)
No description available.
49

A Moessbauer and #mu#SR study of the magnetic ordering of some antiferromagnet compounds

Attenborough, Michael January 1997 (has links)
No description available.
50

A multimodal spectrometer for Raman scattering and near-infrared absorption measurement

Wang, Wenbo 05 September 2012 (has links)
In food and pharmaceutical industries, the compositional complexity of raw materials and products promotes the use of multiple spectroscopic techniques. Availability of complementary methods, e.g., infrared absorption and Raman, is highly desirable. A multimodal Raman/NIR spectroscopic device was proposed. The device offered fast, non-destructive measurement, and remote sensing capability. A prototype was built. Spectral range covered 300-2600 cm-1 for Raman channel. Wavelength accuracy was better than 0.57 nm. Spectral resolution was better than 14.39 cm-1 (1 nm) for Raman (NIR) channel. Spectral response linearity was better than 0.998. Instrumental stability was better than 0.72% (0.39%) for Raman (NIR) channel. The device was applied to quantify ethanol aqueous solutions (2%-10% (v/v)). Quantitation results gave a root mean squared error of prediction (RMSEP) of 0.45% (v/v). Calibration using NIR absorbance spectra produced a RMSEP value of 0.49% (v/v). Raman technique offered the most succinct calibration model using peak height at 882.29 cm-1. Quantitation of ovalbumin (8%-16% (w/v)) in aqueous solutions and denatured states was also attempted. Stepwise multiple regression was performed using Raman peaks at 1243.35, 1448.68, 1662.66, and 1667.78 cm-1, which produced RMSEPs of 1.05 % (w/v) for ovalbumin solutions and 0.74 % (w/v) for ovalbumin gels. Conformational change of ovalbumin upon thermal denaturation was studied using the height and area ratios between peaks at 1243.35 and 1662.66 cm-1. Thermal denaturation of ovalbumin occurred at 70 °C and extensive formation of anti-parallel β-sheet structure was found at 90 °C. The unique capability of this multimodal device was proven by first performing data fusion of Raman and NIR spectra for quantitation. Using the same ethanol spectra set gave a more complicated model and a higher RMSEP of 0.73% (v/v). However, important variables in fused spectra corresponded well with the spectral signatures of ethanol and water. Two-dimensional correlation spectra were calculated using concentration as the external perturbation. The autopower spectra revealed features pertinent to those of the analytes. Heterospectral correlation analysis was carried out on Raman/NIR spectra of ethanol aqueous solution. Raman peaks at 882.29 and 1454.00 cm-1 agreed with the NIR absorption feature around 906.18 nm.

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