Accurate determination of the far-infrared dispersion in SrTiO3by hyper-Raman spectroscopy

The far infrared nebular spectrum provides a valuable complement to the observed lines in other spectral regions. There are several reasons for this, the most important being the large increase in the number of ions observed, and the fact that the abundances found from these lines are relatively insensitive to the electron temperature. This leads to a more accurate determination of the abundances. To date, twelve PN have had abundances determined in this way. These results are summarized. The evolution of the central star is discussed in the light of these results.

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The determination of the Sb/As content in natural tetrahedrite–tennantite and bournonite–seligmannite solid solution series by Raman spectroscopy

Mineralogical Magazine ◽

10.1180/minmag.2017.081.008 ◽

2017 ◽

Vol 81 (6) ◽

pp. 1439-1456 ◽

Cited By ~ 4

Author(s):

A. I. Apopei ◽

G. Damian ◽

N. Buzgar ◽

A. Buzatu ◽

P. Andráš ◽

...

Keyword(s):

Solid Solution ◽

Raman Spectroscopy ◽

Linear Equations ◽

Accurate Determination ◽

Spectroscopic Parameter ◽

Solid Solution Series ◽

Solution Series ◽

Polynomial Fit ◽

Content Ratio

AbstractNatural samples containing tetrahedrite–tennantite, bournonite–seligmannite and geocronite–jordanite from the Coranda-Hondol ore deposit, Romania, were investigated by Raman spectroscopy to determine its capability to provide estimates of solid solutions in three common and widespread sulfosalt mineral series. Raman measurements were performed on extended solid solution series (Td1 to Td97, Bnn25 to Bnn93 and Gcn24 to Gcn67, apfu). The tetrahedrite–tennantite and bournonite–seligmannite solid solution series show strong correlations between spectroscopic parameters ( position, relative intensity and shape of the Raman bands) and the Sb/(Sb+As) content ratio, while Raman spectra of geocronite–jordanite shows no evolution of Raman bands. In order to simplify the method used to estimate the Sb/(Sb+As) content ratio in tetrahedrite–tennantite and bournonite–seligmannite series, several linear equations of the first-order polynomial fit were obtained. The results are in good agreement with electron microprobe data. Moreover, a computer program was developed as an analytical tool for a fast and accurate determination of Sb/(Sb+As) content ratio by at least one spectroscopic parameter. These results indicate that Raman spectroscopy can provide direct information on the composition and structure of the tetrahedrite–tennantite and bournonite– seligmannite series.

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Accurate determination of endpoint temperature of cooked meat after storage by Raman spectroscopy and chemometrics

Food Control ◽

10.1016/j.foodcont.2014.12.011 ◽

2015 ◽

Vol 52 ◽

pp. 119-125 ◽

Cited By ~ 19

Author(s):

Daniel T. Berhe ◽

Anders J. Lawaetz ◽

Søren B. Engelsen ◽

Marchen S. Hviid ◽

René Lametsch

Keyword(s):

Raman Spectroscopy ◽

Accurate Determination ◽

Cooked Meat

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Non-Contact Determination of Free Carrier Concentration in n-GaInAsSb

MRS Proceedings ◽

10.1557/proc-799-z3.5 ◽

2003 ◽

Vol 799 ◽

Author(s):

James E. Maslar ◽

Wilbur S. Hurst ◽

Christine A. Wang ◽

Daniel A. Shiau

Keyword(s):

Raman Spectroscopy ◽

Carrier Concentration ◽

High Speed ◽

Near Infrared ◽

Secondary Ion Mass Spectrometry ◽

Accurate Determination ◽

Free Carrier ◽

Hall Measurements ◽

Gaas Substrates

ABSTRACTGaSb-based semiconductors are of interest for mid-infrared optoelectronic and high-speed electronic devices. Accurate determination of electrical properties is essential for optimizing the performance of these devices. However, electrical characterization of these semiconductors is not straightforward since semi-insulating (SI) GaSb substrates for Hall measurements are not available. In this work, the capability of Raman spectroscopy for determination of the majority carrier concentration in n-GaInAsSb epilayers was investigated. Raman spectroscopy offers the advantage of being non-contact and spatially resolved. Furthermore, the type of substrate used for the epilayer does not affect the measurement. However, for antimonide-based materials, traditionally employed Raman laser sources and detectors are not optimized for the analysis wavelength range dictated by the narrow band gap of these materials. Therefore, a near-infrared Raman spectroscopic system, optimized for antimonide-based materials, was developed.Ga0.85In0.15As0.13Sb0.87 epilayers were grown by organometallic vapor phase epitaxy with doping levels in the range 2 to 80 × 1017 cm-3, as measured by secondary ion mass spectrometry. For a particular nominal doping level, epilayers were grown both lattice matched to n-GaSb substrates and lattice-mismatched to SI GaAs substrates under nominally identical conditions. Single magnetic field Hall measurements were performed on the epilayers grown on SI GaAs substrates, while Raman spectroscopy was used to measure the carrier concentration of epilayers grown on GaSb and the corresponding SI GaAs substrates. Contrary to Hall measurements, Raman spectra indicated that the GaInAsSb epilayers grown on GaSb substrates have higher free carrier concentrations than the corresponding epilayers grown on SI GaAs substrates under nominally identical conditions. This is contrary to the assumption that for nominally identical growth conditions, the resulting carrier concentration is independent of substrate, and possible mechanisms will be discussed.

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Application of Raman spectroscopy in the quality control of injectable medicines

Reference materials ◽

10.20915/2077-1177-2019-15-1-39-53 ◽

2019 ◽

Vol 15 (1) ◽

pp. 39-53

Author(s):

M. P. Krasheninina ◽

M. Yu. Medvedevskikh ◽

E. V. Galeeva ◽

R. R. Galeev

Keyword(s):

Raman Spectroscopy ◽

Quantitative Determination ◽

Accurate Determination ◽

Metrological Traceability ◽

Measurement Procedure ◽

Metrological Characteristics ◽

Active Ingredients ◽

Identification Procedure ◽

Two Component

This paper presents the results of the identification procedure certification and subsequent quantitative determination of the active ingredients of two-component injectable medicines (active ingredient and solvent) using Raman spectroscopy. The main objective of the research was to select approaches for estimating the metrological characteristics of the measurement procedure, which include consideration of the methodological parameters and provide the metrological traceability of measurement results to SI units. According to this purpose, the GVET 176‑1‑2010 State Secondary Measurement Standard for units of mass fraction, mass (molar) concentration of components in solid and liquid substances and materials based on volumetric titration was used. The following substances were chosen as the research objects for estimating the metrological characteristics of the measurement procedure: ascorbic acid, novocaine and sodium thiosulphate. The authors of the work have demonstrated the measurement-procedure certification results, whose accurate determination was confirmed by the results of interlaboratory comparisons. The obtained results confirmed the accuracy of the identification procedure and subsequent quantitative determination, which proves its applicability for the determination of the active ingredients in two-component injectable medicines. In addition, the possibility of developing reference materials based on the medicines under study is indicated. Further development of this study may be directed at the development of an identification procedure and its certification, with subsequent quantitative determination of the active ingredients of injectable medicines having three components as well as those having a more complex composition.

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