Evaluation and Mapping of Heat-Shield Flight Temperature and Composition with Raman Spectroscopic Techniques

1995 ◽  
Vol 49 (5) ◽  
pp. 598-604 ◽  
Author(s):  
D. R. Tallant ◽  
I. Auerbach ◽  
K. L. Higgins
Keyword(s):  
Spectroscopic Technique ◽  
Heat Shield ◽  
Spectroscopic Techniques ◽  
Raman Spectroscopic ◽  
Detailed Surface ◽  
Post Test ◽  
Composition Profiles ◽  
Maximum Temperatures

A Raman spectroscopic technique has been developed which can measure the maximum temperatures experienced by charring heat-shield materials and determine their post-test compositions (char, pyrolysis zone, and virgin resin). The technique has the capabilities of analyzing circular areas less than 0.1 mm in diameter or rectangles 0.1 mm in width and 2 mm in length. It can provide fine detailed surface and internal mappings and perform the analyses rapidly and conveniently in the laboratory following testing or flight recovery. Representative plots of temperature and composition profiles are provided. The data are compared with computations from the Charring Material Ablation (CMA) code.

Crystal structure and temperature-dependent properties of Na2H4Ga2GeO8 – a novel gallogermanate

2020 ◽  
Vol 75 (9-10) ◽  
pp. 805-813
Author(s):  
Irma Peschke ◽  
Lars Robben ◽  
Christof Köhler ◽  
Thomas Frauenheim ◽  
Josef-Christian Buhl ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Decomposition Temperature ◽  
Spectroscopic Techniques ◽  
Charge Balance ◽  
Temperature Dependent ◽  
Raman Spectroscopic ◽  
Debye Temperatures ◽  
Diffraction Lattice ◽  
Temperature Dependent Properties ◽  
Balance Structure

AbstractSynthesis, crystal structure and temperature-dependent behavior of Na2H4Ga2GeO8 are reported. This novel gallogermanate crystallizes in space group I41/acd with room-temperature powder diffraction lattice parameters of a = 1298.05(1) pm and c = 870.66(1) pm. The structure consists of MO4 (M = Ga, Ge) tetrahedra in four-ring chains, which are connected by two different (left- and right-handed) helical chains of NaO6 octahedra. Protons coordinating the oxygen atoms of the GaO4 tetrahedra not linked to germanium atoms ensure the charge balance. Structure solution and refinement are based on single crystal X-ray diffraction measurements. Proton positions are estimated using a combined approach of DFT calculations and NMR, FTIR and Raman spectroscopic techniques. The thermal expansion was examined in the range between T = 20(2) K and the compound’s decomposition temperature at 568(5) K, in which no phase transition could be observed, and Debye temperatures of 266(11) and 1566(65) K were determined for the volume expansion.

Microplasma synthesized gold nanoparticles for surface enhanced Raman spectroscopic detection of methylene blue

2021 ◽  
Author(s):  
Xuanhe Li ◽  
Liangliang Lin ◽  
Wei-Hung Chiang ◽  
Kuan Chang ◽  
Hujun Xu
Keyword(s):  
Rapid Detection ◽  
Chemical Species ◽  
Spectroscopic Technique ◽  
Trace Level ◽  
Raman Spectroscopic ◽  
Non Invasive ◽  
Surface Enhanced ◽  
Surface Enhanced Raman ◽  
Enhanced Raman Scattering ◽  
Non Destructive

Surface enhanced Raman scattering (SERS) is a powerful and sensitive spectroscopic technique that allows for rapid detection of trace-level chemical species in a non-invasive and non-destructive manner. In the present...

scholarly journals The Influence of Storage Conditions on the Biochemical Composition and Morphology of Dahlia Tubers

2016 ◽  
Vol 44 (2) ◽  
pp. 459-465 ◽  
Author(s):  
Ioana CIOBANU ◽  
Maria CANTOR ◽  
Razvan STEFAN ◽  
Erzsebet BUTA ◽  
Klara MAGYARI ◽  
...  
Keyword(s):  
Biochemical Composition ◽  
Storage Conditions ◽  
Spectroscopic Techniques ◽  
Air Humidity ◽  
Raman Spectroscopic ◽  
Pathogen Invasion ◽  
Ft Ir ◽  
Biometric Measurements ◽  
C 30 ◽  
Ft Raman

The aim of this study was to assess by means of biometric measurements and FT-IR and FT-Raman spectroscopic techniques the influence of storage conditions on the morphology and biochemical composition of Dahlia tubers. Investigated samples belong to ‘Kennemerland’ and ‘Red Pygmy’ cultivars of the Dahlia hybrida species, which were preserved over winterat 5-8 °C, 30-40% air humidity in different substrates: sand, sand and sawdust, peat and sawdust. The biometric parameters revealed that the peat and sawdust substrate is the most appropriate one for tubers storage, whereas the sand substrate is the least suitable one. The inulin signature was evidenced in all tuber samples as well as the changes of biochemical composition induced by different storage conditions. The analysis of the FT-IR and FT-Raman spectra demonstrated that the inulinaccumulation inside the tubers is favourably influenced by the sand storage, and depends on the cultivar type. Moreover, it was established that the peat and sawdust substrate favours the polyacetylene formation inside the tubers probably because it facilitates the occurrence and development of pathogens inside the tuber. It was also found that the polyacetylene concentration increased, which is associated with the plant response to the pathogen invasion, depends on the cultivar type.

Comparative chemotype determination of Lamiaceae plants by means of GC–MS, FT-IR, and dispersive-Raman spectroscopic techniques and GC-FID quantification

2014 ◽  
Vol 62 ◽  
pp. 22-33 ◽  
Author(s):  
Raquel Rodríguez-Solana ◽  
Dimitra J. Daferera ◽  
Christina Mitsi ◽  
Panayiotis Trigas ◽  
Moschos Polissiou ◽  
...  
Keyword(s):  
Spectroscopic Techniques ◽  
Raman Spectroscopic ◽  
Ft Ir

The feasibility of using near infrared and Raman spectroscopic techniques to detect fraudulent adulteration of chili powders with Sudan dye

Food Control ◽  
2015 ◽  
Vol 48 ◽  
pp. 75-83 ◽  
Author(s):  
Simon A. Haughey ◽  
Pamela Galvin-King ◽  
Yen-Cheng Ho ◽  
Steven E.J. Bell ◽  
Christopher T. Elliott
Keyword(s):  
Near Infrared ◽  
Spectroscopic Techniques ◽  
Raman Spectroscopic ◽  
Sudan Dye

scholarly journals Natural scientific methods in exploration of reference monuments of the Saka Culture in Kazakh Altai

2020 ◽  
pp. 21-31
Author(s):  
Zainolla Samashev ◽  
Aidos Erbulatovich Chotbaev ◽  
Nikolai Sergeevich Kurganov ◽  
Dmitrii Vasil'evich Pankin ◽  
Anastasiya Valer'evna Povolotskaya ◽  
...  
Keyword(s):  
Spectroscopic Technique ◽  
Organic Substances ◽  
Identification Procedure ◽  
Scientific Methods ◽  
Raman Spectroscopic ◽  
Gold Jewelry ◽  
Material Component ◽  
Modern Natural ◽  
East Kazakhstan ◽  
Subsequent Identification

This article explores the ancient gold jewelry with inlay, which were discovered in the process of archeological studies conducted in Summer 2018 of grave complexes located on the Eleke Sazy Plateau, Tarbagatay Ridge in East Kazakhstan Region in the burial of a young man belonging to aristocratic ancestry. It refers to the Saka culture, and dates back to approximately VIII-VII centuries BC. Among the discovered objects were garments embroidered with gold, quiver with arrows, and a bronze dagger in gold scabbard. This work studied the golden scabbard for dagger. The scabbard consists of several parts attached to a wooden base and decorated with granulation and inlay. In many cases, only traces of inlay remain. Some gems changed in color in the process of degradation, and currently look grey. Micro-samples for the research were selected from the crumbling fragments of inlay obtained in the process of restoration of the item. Modern natural scientific methods allow studying the material component of the objects of cultural heritage. The identification procedure is now available even based on the remaining particles with characteristic sizes that do not exceed tens of microns. Within the framework this research, the author examined the possibility of selecting such micro-samples with subsequent identification. Application of the Raman spectroscopic technique allowed examining the selected micro-samples on the next stage. The complementary methods imply Fourier-transform infrared spectroscopy for studying organic substances the inlay was attached to.

scholarly journals Synthesis, Structural and Optical Investigations of (Pb, Bi)TiO3 Borosilicate Glasses

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Chandkiram Gautam
Keyword(s):  
Spectroscopic Techniques ◽  
Borosilicate Glasses ◽  
X Ray Diffraction ◽  
Raman Spectroscopic ◽  
Spectral Bands ◽  
Prepared Glass ◽  
Infrared And Raman Spectroscopy ◽  
Uv Visible ◽  
Diffraction Patterns ◽  
Spectral Patterns

A new series of lead bismuth titanate borosilicate glasses with addition of one percent lanthanum oxide have been synthesized using melt-quench technique. X-ray diffraction patterns have been recorded to confirm the amorphous nature of the prepared glass samples. The synthesized glasses have been characterized by using various spectroscopic techniques such as UV-visible, infrared, and Raman spectroscopy. UV-visible measurements were recorded in the wavelength range from 200 to 1100 nm whereas IR and Raman spectroscopic measurements were recorded over a continuous wavenumber range from 400 to 5000 cm−1 and 1000 to 2000 cm−1 respectively. The different absorption peaks/bands were formed in IR spectral patterns. The spectral bands appear towards the lower wavenumber sides due to the Bi and Pb, content while the bands appear towards the higher wavenumber sides due to the formation of diborate and triborate network units.

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