scholarly journals Halogens in Eclogite Facies Minerals from the Western Gneiss Region, Norway

Minerals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 760
Author(s):  
Lewis Hughes ◽  
Simon Cuthbert ◽  
Alex Quas-Cohen ◽  
Lorraine Ruzié-Hamilton ◽  
Alison Pawley ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Fluid Inclusions ◽  
Secondary Ion Mass Spectrometry ◽  
Noble Gas ◽  
Minor Component ◽  
Fluid Composition ◽  
Alternative Source ◽  
Western Gneiss Region ◽  
A Minor ◽  
Multi Phase

Ultra-high-pressure (UHP) eclogites and ultramafites and associated fluid inclusions from the Western Gneiss Region, Norwegian Caledonides, have been analysed for F, Cl, Br and I using electron-probe micro-analysis, time-of-flight secondary ion mass spectrometry and neutron-irradiated noble gas mass spectrometry. Textures of multi-phase and fluid inclusions in the cores of silicate grains indicate formation during growth of the host crystal at UHP. Halogens are predominantly hosted by fluid inclusions with a minor component from mineral inclusions such as biotite, phengite, amphibole and apatite. The reconstructed fluid composition contains between 11.3 and 12.1 wt% Cl, 870 and 8900 ppm Br and 6 and 169 ppm I. F/Cl ratios indicate efficient fractionation of F from Cl by hydrous mineral crystallisation. Heavy halogen ratios are higher than modern seawater by up to two orders of magnitude for Br/Cl and up to three orders of magnitude for I/Cl. No correlation exists between Cl and Br or I, while Br and I show good correlation, suggesting that Cl behaved differently to Br and I during subduction. Evolution to higher Br/Cl ratios is similar to trends defined by eclogitic hydration reactions and seawater evaporation, indicating preferential removal of Cl from the fluid during UHP metamorphism. This study, by analogy, offers a field model for an alternative source (continental crust) and mechanism (metasomatism by partial melts or supercritical fluids) by which halogens may be transferred to and stored in the sub-continental lithospheric mantle during transient subduction of a continental margin.

The isolation and identification of makisterone A from the yew, Taxus cuspidata

1977 ◽  
Vol 55 (7) ◽  
pp. 1129-1134 ◽  
Author(s):  
Brenton Garth Burns ◽  
Michael Wilson Gilgan
Keyword(s):  
Mass Spectrometry ◽  
Nuclear Magnetic Resonance ◽  
Trimethylsilyl Ether ◽  
Minor Component ◽  
Reversed Phase ◽  
Taxus Cuspidata ◽  
Isolation And Identification ◽  
Nuclear Magnetic Resonance Spectrometry ◽  
Magnetic Resonance Spectrometry ◽  
A Minor

The ecdysteroids were extracted from yew, Taxus cuspidata, needles and twigs and recovered from the aqueous extract by reversed phase adsorption. Purification of the ecdysteroids was achieved by a single solvent partition and a dry column chromatogram followed by fractionation on an adsorptive Porasil A (60) column. Makisterone A was a minor component identified by melting point, liquid chromatography, gas chromatography of the trimethylsilyl ether, mass spectrometry, and nuclear magnetic resonance spectrometry. A second minor component was isolated but not identified.

scholarly journals Stereoselective synthesis of trans-fused iridoid lactones and their identification in the parasitoid wasp Alloxysta victrix, Part I: Dihydronepetalactones

2012 ◽  
Vol 8 ◽  
pp. 1246-1255 ◽  
Author(s):  
Nicole Zimmermann ◽  
Robert Hilgraf ◽  
Lutz Lehmann ◽  
Daniel Ibarra ◽  
Wittko Francke
Keyword(s):  
Mass Spectrometry ◽  
Stereoselective Synthesis ◽  
Minor Component ◽  
Parasitoid Wasp ◽  
The Other ◽  
Enantiomerically Pure ◽  
Enantioselective Gas Chromatography ◽  
A Minor ◽  
Stereogenic Center ◽  
Reference Samples

Starting from the enantiomers of limonene, all eight stereoisomers of trans-fused dihydronepetalactones were synthesized. Key compounds were pure stereoisomers of 1-acetoxymethyl-2-methyl-5-(2-hydroxy-1-methylethyl)-1-cyclopentene. The stereogenic center of limonene was retained at position 4a of the target compounds and used to stereoselectively control the introduction of the other chiral centers during the synthesis. Basically, this approach could also be used for the synthesis of enantiomerically pure trans-fused iridomyrmecins. Using synthetic reference samples, the combination of enantioselective gas chromatography and mass spectrometry revealed that volatiles released by the endohyperparasitoid wasp Alloxysta victrix contain the enantiomerically pure trans-fused (4R,4aR,7R,7aS)-dihydronepetalactone as a minor component, showing an unusual (R)-configured stereogenic center at position 7.

scholarly journals Stereoselective synthesis of trans-fused iridoid lactones and their identification in the parasitoid wasp Alloxysta victrix, Part II: Iridomyrmecins

2012 ◽  
Vol 8 ◽  
pp. 1256-1264 ◽  
Author(s):  
Robert Hilgraf ◽  
Nicole Zimmermann ◽  
Lutz Lehmann ◽  
Armin Tröger ◽  
Wittko Francke
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Stereoselective Synthesis ◽  
Minor Component ◽  
Parasitoid Wasp ◽  
Enantioselective Gas Chromatography ◽  
A Minor

Following our earlier approach to the synthesis of dihydronepetalactones, all eight stereoisomers of trans-fused iridomyrmecins were synthesized starting from the enantiomers of limonene. Combined gas chromatography and mass spectrometry including enantioselective gas chromatography revealed that volatiles released by the endohyperparasitoid wasp Alloxysta victrix contain (4S,4aR,7S,7aR)-iridomyrmecin of 95–97% ee and stereochemically pure (4S,4aS,7R,7aS)-iridomyrmecin as a minor component.

The Santa Rosa Meteorite from Colombia: An example of critical raw materials in a meteorite

2020 ◽  
Author(s):  
Franziska D.H. Wilke ◽  
Barbara Bsdok ◽  
Uwe Altenberger ◽  
Ana E. Concha
Keyword(s):  
Initial Conditions ◽  
Raw Materials ◽  
Bulk Composition ◽  
Minor Component ◽  
Major Elements ◽  
Iron Meteorite ◽  
Earth Planet ◽  
Alternative Source ◽  
A Minor

<p>Meteorites, especially the undifferentiated ones like primitive chondrites, provide information about the origin and initial conditions of the solar system since they contain presolar and solar nebula materials (Scott, 2007). Differentiated meteorites like iron meteorites play a distinct role in constraining the early phases of planetary accretion (Yang et al. 2007). They also provide the possibility to receive information about core properties and planetary bodies. In addition to the gain in such fundamental scientific knowledge both types are of interest for the exploration of critical and precious elements (CRMs).</p><p>In the future, the tremendous increase of the consumption of these elements from terrestrial deposits and the subsequent shortage could lead to an exploitation of extra-terrestrial deposits. Therefore, “space-mining” of near Earth objects could be used as alternative source of raw materials (Ross, 2001).</p><p>While improving the characterization and classification of the Santa Rosa de Viterbo Iron Meteorite, we found notable concentrations of Au and Ge alongside major elements such as Fe, Ni and Co in the bulk composition of that meteorite. Major and rock-forming minerals such as kamacite and taenite incorporate hundreds of ppm of Ge whereas schreibersite, itself a minor component in that particular meteorite, is a source for Au. In kamacite and taenite also Ir and Ga were found in minor amounts.</p><p> </p><p>Scott, E. R. (2007). Chondrites and the protoplanetary disk. Annu. Rev. Earth Planet. Sci., 35, 577-620.</p><p>Ross, S. D. (2001). Near-earth asteroid mining. Space, 1-24.</p><p>Yang, J., Goldstein, J. I., & Scott, E. R. (2007). Iron meteorite evidence for early formation and catastrophic disruption of protoplanets. Nature, 446(7138), 888.</p><p> </p>

How SIMS microscopy can be used in medicine

1992 ◽  
Vol 50 (2) ◽  
pp. 1602-1603
Author(s):  
Philippe Fragu
Keyword(s):  
Mass Spectrometry ◽  
Biomedical Applications ◽  
Secondary Ion Mass Spectrometry ◽  
Chemical Elements ◽  
Biological Applications ◽  
The Past ◽  
Potential Source ◽  
Secondary Ion ◽  
Chemical Integrity ◽  
Scientific Endeavour

The identification, localization and quantification of intracellular chemical elements is an area of scientific endeavour which has not ceased to develop over the past 30 years. Secondary Ion Mass Spectrometry (SIMS) microscopy is widely used for elemental localization problems in geochemistry, metallurgy and electronics. Although the first commercial instruments were available in 1968, biological applications have been gradual as investigators have systematically examined the potential source of artefacts inherent in the method and sought to develop strategies for the analysis of soft biological material with a lateral resolution equivalent to that of the light microscope. In 1992, the prospects offered by this technique are even more encouraging as prototypes of new ion probes appear capable of achieving the ultimate goal, namely the quantitative analysis of micron and submicron regions. The purpose of this review is to underline the requirements for biomedical applications of SIMS microscopy.Sample preparation methodology should preserve both the structural and the chemical integrity of the tissue.

Imaging of Al-Li-Cu alloys with a Scanning Ion Microprobe

1990 ◽  
Vol 48 (2) ◽  
pp. 314-315
Author(s):  
K.K. Soni ◽  
D.B. Williams ◽  
J.M. Chabala ◽  
R. Levi-Setti ◽  
D.E. Newbury
Keyword(s):  
Mass Spectrometry ◽  
Secondary Ion Mass Spectrometry ◽  
Equilibrium Phase ◽  
Icosahedral Symmetry ◽  
Ion Microprobe ◽  
X Ray ◽  
Cu Alloys ◽  
Two Phases ◽  
The University ◽  
Secondary Ion

In contrast to the inability of x-ray microanalysis to detect Li, secondary ion mass spectrometry (SIMS) generates a very strong Li+ signal. The latter’s potential was recently exploited by Williams et al. in the study of binary Al-Li alloys. The present study of Al-Li-Cu was done using the high resolution scanning ion microprobe (SIM) at the University of Chicago (UC). The UC SIM employs a 40 keV, ∼70 nm diameter Ga+ probe extracted from a liquid Ga source, which is scanned over areas smaller than 160×160 μm2 using a 512×512 raster. During this experiment, the sample was held at 2 × 10-8 torr.In the Al-Li-Cu system, two phases of major importance are T1 and T2, with nominal compositions of Al2LiCu and Al6Li3Cu respectively. In commercial alloys, T1 develops a plate-like structure with a thickness <∼2 nm and is therefore inaccessible to conventional microanalytical techniques. T2 is the equilibrium phase with apparent icosahedral symmetry and its presence is undesirable in industrial alloys.

Applications of Time-OF-Flight Secondary Ion Mass Spectrometry (TOF-SIMS)

1990 ◽  
Vol 48 (2) ◽  
pp. 308-309
Author(s):  
Bruno Schueler ◽  
Robert W. Odom
Keyword(s):  
Mass Spectrometry ◽  
Secondary Ion Mass Spectrometry ◽  
Structural Information ◽  
Time Of Flight ◽  
Biological Tissues ◽  
Polymer Surfaces ◽  
Tof Sims ◽  
Secondary Ions ◽  
Ion Mass Spectrometry ◽  
Secondary Ion

Time-of-flight secondary ion mass spectrometry (TOF-SIMS) provides unique capabilities for elemental and molecular compositional analysis of a wide variety of surfaces. This relatively new technique is finding increasing applications in analyses concerned with determining the chemical composition of various polymer surfaces, identifying the composition of organic and inorganic residues on surfaces and the localization of molecular or structurally significant secondary ions signals from biological tissues. TOF-SIMS analyses are typically performed under low primary ion dose (static SIMS) conditions and hence the secondary ions formed often contain significant structural information.This paper will present an overview of current TOF-SIMS instrumentation with particular emphasis on the stigmatic imaging ion microscope developed in the authors’ laboratory. This discussion will be followed by a presentation of several useful applications of the technique for the characterization of polymer surfaces and biological tissues specimens. Particular attention in these applications will focus on how the analytical problem impacts the performance requirements of the mass spectrometer and vice-versa.

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