scholarly journals Cryogenic Raman Spectroscopic Studies on Common Ore-forming Fluid Systems

Minerals ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 363
Author(s):  
Dan Yang ◽  
Xin Xiong ◽  
Weishi Chen
Keyword(s):  
Raman Spectroscopy ◽  
Quantitative Analysis ◽  
Correlation Coefficient ◽  
Fluid Inclusions ◽  
Intensity Ratio ◽  
Spectroscopic Studies ◽  
Ore Deposits ◽  
Raman Spectroscopic ◽  
Freezing Method ◽  
Fluid Systems

The composition and properties of ore-forming fluids are key to understanding the mechanisms of mineralization in ore deposits. These characteristics can be understood by studying fluid inclusions. Hydrates in fluid inclusions containing NaCl–H2O and MgCl2–H2O were studied using cryogenic Raman spectroscopy. The intensity ratio of peaks at 3401, 3464, 3514, and 3090 cm−1 shows a positive correlation with the concentration of hydrates in the inclusions, as does the ratio of the total integrated area of the MgCl2 hydrate peak (3514 cm−1) to the 3090 cm−1 peak with the concentration of MgCl2 (correlation coefficient >0.90). These correlations are important in the quantitative analysis of MgCl2 in synthetic and natural NaCl–MgCl2–CaCl2–H2O-bearing fluid inclusions. Semi-quantitative analysis of NaCl–MgCl2–H2O solutions indicates that peaks at 3437 and 3537 cm−1 reflect the presence of NaCl in the solution. Further, a peak at 3514 cm−1 is indicative of the presence of MgCl2. The relative intensities of these peaks may be related to the relative abundances of NaCl and MgCl2. A quantitative attempt was made on NaCl–MgCl2–CaCl2–H2O system, but it was found that quantifying NaCl, MgCl2 and CaCl2 separately in NaCl–MgCl2–CaCl2–H2O system by the secondary freezing method is difficult.

A Furnace for Molten Salt Raman Spectroscopy to 800°C

1971 ◽  
Vol 25 (1) ◽  
pp. 82-84 ◽  
Author(s):  
Arvin S. Quist
Keyword(s):  
Raman Spectroscopy ◽  
Laser Beam ◽  
Molten Salts ◽  
Spectroscopic Studies ◽  
Sample Container ◽  
Raman Spectroscopic ◽  
Laser Raman ◽  
Different Types ◽  
Sample Chamber ◽  
Metal Block

A vacuum tight furnace has been constructed and used for laser-Raman spectroscopic studies of molten salts to 800°C. The sample container is positioned within the furnace by a removable metal block, several designs of which have been used with different types of sample containers. The sample under investigation is easily and rapidly aligned in the laser beam by means of micrometer screws located on the positioning table which supports the furnace. The compactness of the entire unit allows it to be readily moved into and out of the sample chamber of the spectrometer.

Quantitative analysis and measurement of carbon isotopic compositions in individual fluid inclusions by micro-laser Raman spectrometry

2016 ◽  
Vol 8 (37) ◽  
pp. 6730-6738 ◽  
Author(s):  
Jiajia Li ◽  
Rongxi Li ◽  
Bangsheng Zhao ◽  
Ning Wang ◽  
Jinghua Cheng
Keyword(s):  
Raman Spectroscopy ◽  
Quantitative Analysis ◽  
Fluid Inclusions ◽  
Laser Raman Spectroscopy ◽  
Raman Spectrometry ◽  
Laser Raman ◽  
Isotopic Compositions ◽  
Carbon Isotopic ◽  
Non Destructive

Micro-laser Raman spectroscopy is a non-destructive technique to quantitatively determine the carbon isotopic compositions of CO2 in individual fluid inclusions.

In situ quantitative analysis of individual H2O–CO2 fluid inclusions by laser Raman spectroscopy

2007 ◽  
Vol 237 (3-4) ◽  
pp. 255-263 ◽  
Author(s):  
Tristan Azbej ◽  
Matthew J. Severs ◽  
Brian G. Rusk ◽  
Robert J. Bodnar
Keyword(s):  
Raman Spectroscopy ◽  
Quantitative Analysis ◽  
Fluid Inclusions ◽  
Laser Raman Spectroscopy ◽  
Laser Raman

Raman Spectroscopic Studies of Amsacrine

1992 ◽  
Vol 46 (10) ◽  
pp. 1540-1544 ◽  
Author(s):  
Catherine A. Butler ◽  
Ralph P. Cooney ◽  
William A. Denny
Keyword(s):  
Crystal Structure ◽  
Raman Spectroscopy ◽  
Crystal Structure Data ◽  
Visible Spectrum ◽  
Spectroscopic Studies ◽  
Resonance Raman Spectrum ◽  
Raman Spectroscopic ◽  
Ft Raman Spectroscopy ◽  
Uv Visible ◽  
Ft Raman

Amsacrine (4′-(9-acridinylamino)methanesulfon- m-anisidide) in both solid and aqueous forms was characterized with the use of resonance and nonresonance Raman spectroscopy (including FT-Raman spectroscopy). Evidence that the acridine nucleus is the dominant chromophoric unit contributing to the resonance Raman spectrum is based upon the apparent similarities of the spectra of aqueous amsacrine (in the unpro-tonated form) and acridine (in ethanol). The probable non-coplanarity of the acridine and phenyl units in the amsacrine molecule (based on previously reported crystal structure data) is consistent with the suggestion that the acridine nucleus may constitute an independent chromophoric unit. Further evidence is derived from analysis of the UV-visible spectrum, which indicates that excitation at 457.9 nm falls within an electronic transition of the acridine nucleus of amsacrine. The excitation profiles of aqueous amsacrine are presented, and four types of profiles have been identified.

scholarly journals Operando Raman spectroscopic studies of lithium zirconates during CO2 capture at high temperature

RSC Advances ◽  
2016 ◽  
Vol 6 (10) ◽  
pp. 8222-8231 ◽  
Author(s):  
Diana Peltzer ◽  
John Múnera ◽  
Laura Cornaglia
Keyword(s):  
Raman Spectroscopy ◽  
High Temperature ◽  
Co2 Capture ◽  
Phase Evolution ◽  
Spectroscopic Studies ◽  
Capture Process ◽  
Raman Spectroscopic

Operando Raman spectroscopy allowed following up the phase evolution for K-doped lithium zirconates during the CO2 capture process.

scholarly journals Phase transitions in natural C-O-H-N-S fluid inclusions - implications for gas mixtures and the behavior of solid H2S at low temperatures

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Marta Sośnicka ◽  
Volker Lüders
Keyword(s):  
Phase Transitions ◽  
Low Temperature ◽  
Fluid Inclusions ◽  
Gas Mixtures ◽  
Complete Sequence ◽  
Future Research ◽  
Raman Spectroscopic ◽  
Fluid Systems ◽  
Phase Transition Temperatures ◽  
World Class

AbstractC–O–H–N–S-bearing fluids are known as one of the most challenging geochemical systems due to scarcity of available experimental data. H2S-rich fluid systems were recognized in a wide array of world-class mineral deposits and hydrocarbon reservoirs. Here we report on a nature of low-temperature (T ≥ −192 °C) phase transitions observed in natural CH4–H2S–CO2–N2–H2O fluid inclusions, which are modeled as closed thermodynamic systems and thus serve as natural micro-laboratories representative of the C–O–H–N–S system. For the first time, we document solid–solid H2S (α ↔ β ↔ γ) transitions, complex clathrates and structural transformations of solid state H2S in natural inclusion gas mixtures. The new data on Raman spectroscopic features and a complete sequence of phase transition temperatures in the gas mixtures contribute to scientific advancements in fluid geochemistry. Enhanced understanding of the phase equilibria in the C–O–H–N–S system is a prerequisite for conscientious estimation of P-T-V-X properties, necessary to model the geologic evolution of hydrocarbon and mineral systems. Our findings are a driver for the future research expeditions to extraterrestrial H2S-rich planetary systems owing to their low temperature environments.

Raman Spectroscopic Studies of the Vulcanization of Rubbers. II. Raman Spectroscopic Studies as a Function of Cure Time

1971 ◽  
Vol 44 (4) ◽  
pp. 904-913 ◽  
Author(s):  
J. R. Shelton ◽  
J. L. Koenig ◽  
M. M. Coleman
Keyword(s):  
Raman Spectroscopy ◽  
Raman Line ◽  
Spectroscopic Studies ◽  
Conjugated Dienes ◽  
The Other ◽  
Asymptotic Dependence ◽  
Raman Spectroscopic ◽  
Cure Time ◽  
Conjugated Triene ◽  
Vulcanization Process

Abstract It has been demonstrated that Raman spectroscopy can be used to follow changes that occur in the network of vulcanizates as a function of cure time. In the system studied we have found that dialkenyl sulfides, cyclic sulfides and conjugated triene structures parallel the cure. In other words, the Raman lines due to these structures display an asymptotic trend as a function of cure time with the plateau occurring in the region of the optimum cure time. On the other hand those Raman lines assigned to the trans isomer and conjugated dienes do not exhibit the same asymptotic dependence as a function of cure time but show an increase in intensity as the cure time is prolonged up to at least 2 hours at 150° C. This would appear to indicate that these Raman lines are not solely associated with the vulcanization process but that thermal and allied processes may contribute. The Raman line occurring at 440 cm−1 does not show any definitive trend and is unlikely to be associated directly with the network. It is most probably due to unextracted extra-network ZnO present.

scholarly journals Raman Spectroscopy for Quantitative Analysis of Point Defects and Defect Clusters in Irradiated Graphite

2012 ◽  
Vol 2012 ◽  
pp. 1-14 ◽  
Author(s):  
Keisuke Niwase
Keyword(s):  
Raman Spectroscopy ◽  
Quantitative Analysis ◽  
Raman Spectra ◽  
Intensity Ratio ◽  
Irradiation Time ◽  
Amorphous State ◽  
Raman Intensity ◽  
Defect Clusters ◽  
Accumulation Model ◽  
Irradiated Graphite

We report the development of Raman spectroscopy as a powerful tool for quantitative analysis of point defect and defect clusters in irradiated graphite. Highly oriented pyrolytic graphite (HOPG) was irradiated by 25 keV He+ and 20 keV D+ ions. Raman spectroscopy and transmission electron microscopy revealed a transformation of irradiated graphite into amorphous state. Annealing experiment indicated a close relation between Raman intensity ratio and vacancy concentration. The change of Raman spectra under irradiation was empirically analyzed by “disordered-region model,” which assumes the transformation from vacancy-contained region to disordered region. The model well explains the change of Raman spectra and predicts the critical dose of amorphization, but the nature of the disordered region is unclear. Then, we advanced the model into “dislocation accumulation model,” assigning the disordered region to dislocation dipole. Dislocation accumulation model can simulate the irradiation time dependencies of Raman intensity ratio and the c-axis expansion under irradiation, giving a relation between the absolute concentration of vacancy and Raman intensity ratio, suggesting an existence of the barrier on the mutual annihilation of vacancy and interstitial.

scholarly journals Quantification of Solute Composition in H2O-NaCl-CaCl2 Solutions Using Cryogenic 2D Raman Mapping

Minerals ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1043
Author(s):  
Haixia Chu ◽  
Guoxiang Chi ◽  
Chunji Xue
Keyword(s):  
Raman Spectroscopy ◽  
Quantitative Analysis ◽  
Fluid Inclusions ◽  
Molar Fraction ◽  
Mapping Technique ◽  
Raman Mapping ◽  
Point Analysis ◽  
Single Inclusion ◽  
Solute Composition ◽  
Non Destructive

Various analytical techniques have been developed to determine the solution composition of fluid inclusions, including destructive, non-destructive, single-inclusion, and bulk-inclusion methods. Cryogenic Raman spectroscopy, as a non-destructive and single-inclusion method, has emerged as a potentially powerful tool of quantitative analysis of fluid inclusion composition. A method of point analysis using cryogenic Raman spectroscopy has been previously proposed to quantitatively estimate the solute composition of H2O-NaCl-CaCl2 solutions, but there are uncertainties related to heterogeneity of frozen fluid inclusions and potential bias in the processing of Raman spectra. A new method of quantitative analysis of solute composition of H2O-NaCl-CaCl2 solutions using Raman mapping technology is proposed in this study, which can overcome the problems encountered in the point analysis. It is shown that the NaCl/(NaCl + CaCl2) molar ratio of the solution, X(NaCl, m), can be related to the area fraction of hydrohalite over hydrohalite plus antarcticite, Fhydrohalite, by the equation X(NaCl, m) = 1.1435 Fhydrohalite − 0.0884, where Fhydrohalite = hydrohalite area/(hydrohalite area + antarcticite area). This equation suggests that the molar fraction of a salt component may be estimated from the fraction of the Raman peak area of the relevant hydrate. This study has established a new way of estimating solute composition of fluid inclusions using cryogenic Raman mapping technique, which may be extended to other solutions.

Sign in / Sign up

Export Citation Format

Share Document