scholarly journals Meridianiite detected in ice

2009 ◽  
Vol 55 (189) ◽  
pp. 117-122 ◽  
Author(s):  
F. Elif Genceli ◽  
Shinichirou Horikawa ◽  
Yoshinori Iizuka ◽  
Toshimitsu Sakurai ◽  
Takeo Hondoh ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Low Temperature ◽  
Sea Ice ◽  
Magnesium Sulfate ◽  
Raman Spectra ◽  
Sulfate Salt ◽  
Micro Raman Spectroscopy ◽  
Naturally Occurring ◽  
Formation History ◽  
History Of

AbstractInclusions affect the behavior of ice, and their characteristics help us understand the formation history of the ice. Recently, a low-temperature magnesium sulfate salt was discovered. This paper describes this naturally occurring MgSO4·11H2O mineral, meridianiite, derived from salt inclusions in sea ice of Lake Saroma, Japan and in Antarctic continental core ice. Its occurrence is confirmed by using micro-Raman spectroscopy to compare Raman spectra of synthetic MgSO4·11H2O with those of the inclusions.

Raman Spectra of Human Dental Calculus

1993 ◽  
Vol 72 (12) ◽  
pp. 1609-1613 ◽  
Author(s):  
H. Tsuda ◽  
J. Arends
Keyword(s):  
Raman Spectroscopy ◽  
Raman Spectra ◽  
Octacalcium Phosphate ◽  
Spot Size ◽  
Spectral Features ◽  
Dental Calculus ◽  
Micro Raman Spectroscopy ◽  
Vibrational Bands ◽  
First Time ◽  
Mineral Constituents

Raman spectra of human dental calculus have been observed for the first time by use of micro-Raman spectroscopy. The spectral features of calculus were influenced easily by heating caused by laser irradiation. Therefore, the measurements were carried out at relatively low power (5 mW, 1-μm spot size). The spectra could be characterized as phosphate vibrational bands due to the v1, v2, v 3, and v4 modes. The overall spectral features did not resemble those of pure minerals such as brushite, octacalcium phosphate, and hydroxyapatite. There were spectral differences among mixed calculus particles obtained from 18 adults, probably due to variations in local mineral composition and differences among patients. However, the averaged spectral features did not vary significantly with formation period from 1 to 6 months. Freshly removed and stored (5-11 months) calculus also gave comparable Raman spectra. Measurements on a fractured sample indicated that Raman spectra at saliva and dentin interfaces are nearly identical, and major mineral constituents may not vary significantly along the growth axis of calculus.

The determination of composition and thermal history of plagioclase by the X-ray powder method

1955 ◽  
Vol 30 (229) ◽  
pp. 648-656 ◽  
Author(s):  
J. Goodyear ◽  
W. J. Duffin
Keyword(s):  
Chemical Composition ◽  
Low Temperature ◽  
Similar Composition ◽  
X Ray ◽  
Naturally Occurring ◽  
Cell Dimensions ◽  
History Of ◽  
Unit Cell Dimensions ◽  
Ray Patterns

In a recent paper (hereafter referred to as GD) Goodyear and Dufiln (1954) described X-ray powder data for a number of synthetic and chemically analysed plagioclases of composition An0Abl00-Anl00Ab0. Important aspects of this work were a correlation of the X-ray patterns with chemical composition, and a distinction between the pattern of a naturally occurring material of low-temperature origin and that of a synthetic of similar composition. The investigation showed quite clearly that the unit-cell dimensions of a synthetic plagioelase depend but little on composition from An0Abl00 to An70Ab30, whilst they differ from those of the low-temperature modification greatly for albite, to a lessening degree as the composition approaches An70Ab30, and practically not at all in the range An70Ab30-Anl00Ab0.

Nachweis der isotopomeren closo-Hydrohexaborate 11Bn10B6-nH62- , n = 0—6, durch Tieftemperatur-Raman-Spektroskopie / Detection of the Isotopomeric closo-Hydrohexaborates 11Bn10B6-nH62- , n = 0—6, by Low Temperature Raman Spectroscopy

1989 ◽  
Vol 44 (2) ◽  
pp. 121-126 ◽  
Author(s):  
W. Preetz ◽  
J. Thesing
Keyword(s):  
Raman Spectroscopy ◽  
Low Temperature ◽  
Raman Spectra ◽  
Abundance Ratio ◽  
Geometric Isomers ◽  
First Time

Abstract The low temperature Raman spectra (10 K) of Cs2B6H6 and its 11B and 10B enriched derivatives prepared for the first time show well resolved signals o f the B6-cage vibrations υ1 (A1g), υ3(Eg) and υ9(T2g) for all isotopomers 11B10B6-nH62 -, n = 0-6. The intensities o f the sharp peaks correlate exactly with the statistical abundance ratio. W hereas the frequency decreases by nearly equidistant steps of 7 cm-1 with increasing n values, the geometric isomers for n = 2, 3 and 4 are separated by only about 2 cm-1. The band assignments are verified by Teller-Redlich calculations.

scholarly journals Molecular Microspectroscopy: Where are we and where are we going

1996 ◽  
Vol 4 (10) ◽  
pp. 12-13
Author(s):  
John A. Reffner
Keyword(s):  
Raman Spectroscopy ◽  
Chemical Analysis ◽  
Light Microscopy ◽  
Molecular Orientation ◽  
Crystalline State ◽  
Microscopic Scale ◽  
Commercial Success ◽  
Infrared Microspectroscopy ◽  
Micro Raman Spectroscopy ◽  
History Of

Molecular microspectroscopy is the application of infrared or Raman spectrascopy, combined with light microscopy, for chemical analysis on the microscopic scale. For over a decade infrared microspectroscopy (ISM) has been an expanding technology both scientifically and commercially. Micro- Raman spectroscopy has a long history of scientific accomplishments with limited commercial success. Both of these techniques give spectral data that can be related to the bonding, crystalline state, isotopic content and molecular orientation of a material, but not its elemental composition.

scholarly journals Raman Spectroscopy as a Potential Tool for Detection of Brucella spp. in Milk

2012 ◽  
Vol 78 (16) ◽  
pp. 5575-5583 ◽  
Author(s):  
Susann Meisel ◽  
Stephan Stöckel ◽  
Mandy Elschner ◽  
Falk Melzer ◽  
Petra Rösch ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Single Cell ◽  
Raman Spectra ◽  
Detection System ◽  
Support Vector ◽  
Promising Alternative ◽  
Content Type ◽  
Micro Raman Spectroscopy ◽  
Genotypic Characteristics ◽  
Potential Tool

ABSTRACTDetection ofBrucella, causing brucellosis, is very challenging, since the applied techniques are mostly time-demanding and not standardized. While the common detection system relies on the cultivation of the bacteria, further classical typing up to the biotype level is mostly based on phenotypic or genotypic characteristics. The results of genotyping do not always fit the existing taxonomy, and misidentifications between genetically closely related genera cannot be avoided. This situation gets even worse, when detection from complex matrices, such as milk, is necessary. For these reasons, the availability of a method that allows early and reliable identification of possibleBrucellaisolates for both clinical and epidemiological reasons would be extremely useful. We evaluated micro-Raman spectroscopy in combination with chemometric analysis to identifyBrucellafrom agar plates and directly from milk: prior to these studies, the samples were inactivated via formaldehyde treatment to ensure a higher working safety. The single-cell Raman spectra of differentBrucella,Escherichia,Ochrobactrum,Pseudomonas, andYersiniaspp. were measured to create two independent databases for detection in media and milk. Identification accuracies of 92% forBrucellafrom medium and 94% forBrucellafrom milk were obtained while analyzing the single-cell Raman spectra via support vector machine. Even the identification of the other genera yielded sufficient results, with accuracies of >90%. In summary, micro-Raman spectroscopy is a promising alternative for detectingBrucella. The measurements we performed at the single-cell level thus allow fast identification within a few hours without a demanding process for sample preparation.

Raman spectroscopic determination of phase evolutions in LiAlxCo1−xO2 battery materials

2001 ◽  
Vol 16 (1) ◽  
pp. 1-4 ◽  
Author(s):  
P. S. Dobal ◽  
R. S. Katiyar ◽  
M. S. Tomar ◽  
A. Hidalgo
Keyword(s):  
Raman Spectroscopy ◽  
Low Temperature ◽  
Raman Spectra ◽  
Sintering Temperature ◽  
Monoclinic Space Group ◽  
Battery Materials ◽  
Space Group ◽  
Raman Spectroscopic ◽  
Al Content

Superior battery materials LiAlxCo1−xO2 (x = 0.0, 0.1, 0.3, 0.5, and 0.7) were synthesized using a solution-based route at various sintering temperatures (450–800 °C). In this communication, we report on the use of Raman spectroscopy to study effect of composition and sintering temperature on the resulting material. The phase evolutions in LiAlxCo1−xO2 compositions were studied using micro-Raman spectroscopy and a phase diagram is proposed based on the observations. For less Al content, the low-temperature phases of LiAlxCo1−xO2 showed Raman spectra corresponding to a monoclinic (space group C2/m) structure, while a low-temperature spinel (space group Fd3m) phase was observed for 50% or more Al in these compounds. All these compositions exhibited a layered hexagonal (space group R3m) structure when sintered above 700 °C. Raman spectra also revealed residual Co3O4 in the low-temperature forms of LiCoO2 and LiA10.01Co0.9O2.

Micro-Raman Characterization of Unusual Defect Structure in Arsenic-Implanted Silicon

1999 ◽  
Vol 588 ◽  
Author(s):  
David D. Tuschel ◽  
James P. Lavine
Keyword(s):  
Raman Spectroscopy ◽  
Raman Spectra ◽  
Defect Structure ◽  
Optical Mode ◽  
Micro Raman Spectroscopy ◽  
Lattice Damage ◽  
Spatially Varying ◽  
Raman Characterization ◽  
Extensive Damage

AbstractRaman spectroscopy has often been used to study the damage to semiconductors induced by ion implantation. Off-axis, macro-Raman spectra reveal extensive damage to the silicon lattice, consistent with many literature reports. However, when the same samples were analyzed in the backscattering mode by micro-Raman spectroscopy, evidence was found for orientational dependent lattice damage and an unusual defect structure. P/O micro-Raman spectra reveal the spatially-varying appearance of a band between 505 and 510 cm−1 always accompanied by that of the silicon optical mode at 520 cm−1.

scholarly journals Evaluation of Deformation Temperatures in Carbonate Mylonites at Low Temperature Thrust-Tectonic Settings via Micro-Raman Spectroscopy

Minerals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1068
Author(s):  
Alessandro Croce ◽  
Enrico Pigazzi ◽  
Patrizia Fumagalli ◽  
Caterina Rinaudo ◽  
Michele Zucali
Keyword(s):  
Raman Spectroscopy ◽  
Low Temperature ◽  
Carbonate Rocks ◽  
Carbonaceous Material ◽  
Fold Belt ◽  
Micro Raman Spectroscopy ◽  
Axial Part ◽  
Laser Sources ◽  
Tectonic Settings ◽  
532 Nm

Carbonaceous materials (CMs) have been widely used to assess temperatures in sedimentary and metamorphic carbonate rocks. The use of Raman spectroscopy of carbonaceous material (RSCM) is largely devoted to the study of deformed rocks hosted in thrust-tectonic settings. Raman spectroscopy of carbonaceous material successfully allows the study of carbonate rocks at a temperature as high as 650 °C. In this study, a set of carbonate-mylonite rocks (Italian Alps) were investigated using micro-Raman spectroscopy, in order to infer the deformation conditions associated with the Alpine thrusts, expected to occur at T < 350 °C. Micro-Raman spectra were collected using two sources: green (532 nm) and red (632.8 nm) lasers. Several deconvolution procedures and parameters were tested to optimize the collected spectrum morphologies for the laser sources, also in accordance with the low temperature expected. The obtained temperatures highlight two clusters: one at 340–350 °C for the samples collected in the axial part of the Alpine chain, and the other at 200–240 °C for those collected in the external thrust-and-fold belt. These results agree with the independent geological and petrological constraints. Consistent results were obtained using 532 and 632.8 nm laser sources when the appropriate deconvolution approach was used.

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