The partition coefficients of Nd and Sm for the sulphides: first data from Palaeoproterozoic layered Cu-Ni-PGE complexes of Fennoscandian Shield

Mapping Intimacies ◽

10.5194/egusphere-egu21-5518 ◽

2021 ◽

Author(s):

Pavel Serov ◽

Tamara Bayanova

Keyword(s):

Partition Coefficients ◽

Sulfide Minerals ◽

Spectrometric Method ◽

New Mineral ◽

Mass Spectrometric Method ◽

Time Data ◽

Mean Values ◽

Geological Processes ◽

Ore Minerals ◽

Monchegorsk Pluton

The Sm-Nd systematics is one of the most demanded isotope-geochronological tools to study ancient geological complexes. With the accumulation of knowledge about the REE in various geological processes, the question arises of extending the capabilities of the Sm-Nd method by using new mineral geochronometers. The research focused on defining the time of the ore process and its position in the general geochronological scale of formation of the geological site become particularly important. There is a pressing need for defining possible forms of REE occurrence in a lattice of geochronometer minerals in the Sm-Nd study of accessory minerals (e.g. fluorite, burbankite, eudialite, ruthile, etc.) and ore minerals (ilmenite, chrome-spinellid, sulfide minerals). The Sm-Nd method of dating ore processes using sulphide minerals, successfully used on several geological objects, made it possible to determine the main stages of ore formation and confirm geochronologically the conclusions about the syngenetic or epigenetic nature of the ore process.Pyrite, pentlandite, chalcopyrite and pyrrhotite from the main industrial fields of the Fennoscandinavian shield were studied: Monchegorsk pluton, Fedorovo-Pansky intrusion, Pechenga, Penicat intrusion and Ahmavaara (Finland). Using a mass-spectrometric method 35 sulphide monofractions were analyzed. The partition coefficients for Nd and Sm were established: for pyrite - 0.229 (Nd) and 0.169 (Sm); for pyrrhotite - 0.265 (Nd) and 0.160 (Sm); for chalcopyrite - 0.229 (Nd) and 0.161 (Sm); for pentlandite &#8211; 0.158 (Nd) and 0.082 (Sm). The mean values for DNd are 0.201, for DSm=0.145 and resulting DNd/DSm about 1.4.Probably, the distribution of REE in sulfide minerals is inherited from fluids during sulfide formation. REE concentrations in sulphide may reflect the composition of the fluid.Thus, for the first time data on Sm and Nd concentrations have been obtained by mass spectrometry. Coefficients of neodymium and samarium distribution in sulfides have been calculated for major Cu-Ni-PGE complexes of Fennoscandia.&#160;This study performed under the theme of scientific research 0226-2019-0053 and were supported by the RFBR &#160;18-05-70082.

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Tandem Mass Spectrometric Evaluation of Core Structures of Aromatic Compounds after Catalytic Deoxygenation

10.26434/chemrxiv.5410807.v1 ◽

2017 ◽

Author(s):

Xueming Dong

Keyword(s):

Aromatic Compounds ◽

Supported Catalyst ◽

Mass Spectrometric ◽

Spectrometric Method ◽

Mass Spectrometric Method ◽

Aromatic Rings ◽

Tandem Mass Spectrometric ◽

Catalytic Deoxygenation ◽

Oxygen Atoms

Catalytic deoxygenation of coal enhances the stability and combustion performance of coal-derived liquids. However, determination of the selectivity of removal of oxygen atoms incorporated in or residing outside of aromatic rings is challenging. This limits the ability to evaluate the success of catalytic deoxygenation processes. A mass spectrometric method, in-source collision-activated dissociation (ISCAD), combined with high resolution product ion detection, is demonstrated to allow the determination of whether the oxygen atoms in aromatic compounds reside outside of aromatic rings or are part of the aromatic system, because alkyl chains can be removed from aromatic cores via ISCAD. Application of this method for the analysis of a subbituminous coal treated using a supported catalyst revealed that the catalytic treatment reduced the number of oxygen-containing heteroaromatic rings but not the number of oxygen atoms residing outside the aromatic rings.

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Tandem Mass Spectrometric Evaluation of Core Structures of Aromatic Compounds after Catalytic Deoxygenation

10.26434/chemrxiv.5410807 ◽

2017 ◽

Author(s):

Xueming Dong

Keyword(s):

Aromatic Compounds ◽

Supported Catalyst ◽

Mass Spectrometric ◽

Spectrometric Method ◽

Mass Spectrometric Method ◽

Aromatic Rings ◽

Tandem Mass Spectrometric ◽

Catalytic Deoxygenation ◽

Oxygen Atoms

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Mass Spectrometric Calibration Procedure for Real-Time Detection of Lighter Hydrocarbons

Energies ◽

10.3390/en14082123 ◽

2021 ◽

Vol 14 (8) ◽

pp. 2123

Author(s):

Makuachukwu F. Mbaegbu ◽

Puspa L. Adhikari ◽

Ipsita Gupta ◽

Mathew Rowe

Keyword(s):

Real Time ◽

Mass Spectrometer ◽

Calibration Procedure ◽

Mass Spectrometric ◽

Spectrometric Method ◽

Mass Selection ◽

Mass Spectrometric Method ◽

Mass Spectrometers ◽

Drilling Rig

Determining gas compositions from live well fluids on a drilling rig is critical for real time formation evaluation. Development and utilization of a reliable mass spectrometric method to accurately characterize these live well fluids are always challenging due to lack of a robust and effectively selective instrument and procedure. The methods currently utilized need better calibration for the characterization of light hydrocarbons (C1–C6) at lower concentrations. The primary goal of this research is to develop and optimize a powerful and reliable analytical method to characterize live well fluid using a quadruple mass spectrometer (MS). The mass spectrometers currently being used in the field have issues with detection, spectra deconvolution, and quantification of analytes at lower concentrations (10–500 ppm), particularly for the lighter (<30 m/z) hydrocarbons. The objectives of the present study are thus to identify the detection issues, develop and optimize a better method, calibrate and QA/QC the MS, and validate the MS method in lab settings. In this study, we used two mass spectrometers to develop a selective and precise method to quantitatively analyze low level lighter analytes (C1–C6 hydrocarbons) with masses <75 m/z at concentrations 10–500 ppm. Our results suggest that proper mass selection like using base peaks with m/z 15, 26, 41, 43, 73, and 87, respectively, for methane, ethane, propane, butane, pentane, and hexane can help detect and accurately quantify hydrocarbons from gas streams. This optimized method in quadrupole mass spectrometer (QMS) will be invaluable for early characterization of the fluid components from a live hydrocarbon well in the field in real time.

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Development of a mass spectrometric method to quantitate platelet activating factor in mouse urine.

The Journal of Lipid Research ◽

10.1016/s0022-2275(20)38209-2 ◽

1989 ◽

Vol 30 (12) ◽

pp. 1977-1981

Author(s):

E Benfenati ◽

D Macconi ◽

M Noris ◽

G Icardi ◽

L Bettazzoli ◽

...

Keyword(s):

Platelet Activating Factor ◽

Mass Spectrometric ◽

Spectrometric Method ◽

Mass Spectrometric Method ◽

Mouse Urine

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Development and validation of a liquid chromatography-tandem mass spectrometric method for the determination of lenalidomide in human plasma and its application on bioequivalence studies

Journal of Analytical Science & Technology ◽

10.1186/s40543-019-0195-z ◽

2019 ◽

Vol 10 (1) ◽

Author(s):

R. Gopinath ◽

S. T. Narenderan ◽

M. Kumar ◽

B. Babu

Keyword(s):

Liquid Chromatography ◽

Human Plasma ◽

Internal Standard ◽

Spectrometric Method ◽

Tandem Mass ◽

Mass Spectrometric Method ◽

Mass Detection ◽

Triple Quadrupole Mass Spectrometer ◽

Liquid Chromatography Tandem Mass ◽

Tandem Mass Spectrometric

AbstractA simple, sensitive, and specific liquid chromatography-tandem mass spectrophotometry (LC-MS/MS) method was developed and validated for the quantification of lenalidomide in human plasma. The separation was carried out on a symmetry, C18, 5-μm (50 × 4.6 mm) column as stationary phase and with an isocratic mobile phase of 0.1% formic acid in water-methanol in the ratio of (15:85, v/v) at a flow rate of 0.5 mL/min. Protonated ions formed by electrospray ionization in the positive mode were used to detect analyte and fluconazole (internal standard). The mass detection was made by monitoring the fragmentation of m/z 260.1/148.8 for lenalidomide and m/z 307.1/238.0 for internal standard on a triple quadrupole mass spectrometer. The developed method was validated over the concentration range of 10–1000 ng/mL for lenalidomide in human plasma with a correlation coefficient (r2) was 0.9930. The accuracy and precision values obtained from six different sets of quality control samples analyzed on separate occasions ranged from 99.41 to 106.97% and 2.88 to 4.22%, respectively. Mean extraction recoveries were 98.06% and 88.78% for the analyte and IS, respectively. The developed method was successfully applied for analyzing lenalidomide in human plasma samples.

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