Search results for "SIMS"

Extensive, water-rich magma reservoir beneath southern Montserrat

2016

South Soufriere Hills and Soufriere Hills volcanoes are two km apart at the southern end of the island of Montserrat, West Indies. Their magmas are distinct geochemically, despite these volcanoes having been active contemporaneously at 131-129 ka. We use the water content of pyroxenes and melt inclusion data to reconstruct the bulk water contents of magmas and their depth of storage prior to eruption. Pyroxenes contain up to 281 ppm H2O, with significant variability between crystals and from core to rim in individual crystals. The Al content of the enstatites from Soufriere Hills Volcano (SHV) is used to constrain melt-pyroxene partitioning for H2O. The SHV enstatite cores record melt water…

The influence of Sb doping on the local structure and disorder in thermoelectric ZnO:Sb thin films

2023

The experiment at HASYLAB/DESY was performed within the project I-20200161 EC. The research leading to this result has been supported by the project CALIPSOplus under the Grant Agreement 730872 from the EU Framework Programme for Research and Innovation HORIZON 2020. Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union's Horizon 2020 Framework Programme H2020-WIDESPREAD-01–2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART2. This work was carried out in part through the use of the INL Advanced Electron Microscopy, Imaging and Spectroscopy Facility. This work (proposal ID 2018–020-022469) was car…

Microstructure-specific carbon isotopic signatures of organic matter from ∼3.5 Ga cherts of the Pilbara Craton support a biologic origin.

2016

21 pages; International audience; The ∼3.5 Ga Dresser Formation from the North Pole Dome of the Pilbara Craton (Western Australia) contains some of the oldest evidence for life on Earth. Here, we present a detailed study of microstructure-specific carbon isotopic composition of organic matter (OM) preserved in Dresser Formation bedded cherts and hydrothermal chert vein using in situ Secondary-Ion Mass Spectrometry (SIMS). The OM in these rocks occurs mainly as clots that, together with minor fine OM layers and laminae, are considered primary textures formed prior to host rock lithification. Other than rare OM-rich stylolites, no evidence was found for later OM migration beyond the micromete…

Struktūra un fotofizikālie procesi 0D un 1D InGaN kompozītu materiālos

2014

Šajā disertācijā tiek aprakstīti strukturālās un fotofizikālās MOCVD izaudzēto GaN nanovadu (NV) un InGaN kvantu punktu (KP) īpašības. Abos gadījumos ir parādīts, ka ex-situ RHEED mērījumi ir iespējami un sniedz kvalitatīvu informāciju par struktūru. Kombinācijā ar citām metodēm, pirmkārt, ir parādīts, ka nemetāliskā katalizatora veicinātā GaN NV īpašības, kad sintezēts uz GaN (0001) virsmas, atšķiras no tradicionāli iegūtajiem. Šinī gadījumā katalizators lokalizējas pie nanovadu pamatnes nevis tā galā un augšanas virziens ir atšķirīgs no kristalogrāfiskās c-ass, rezultātā iegūstot semipolārās NV struktūras. Otrkārt, InGaN kvantu punktos ir konstatēt saspiesta kristāliskā režģa struktūra au…

Simon Lissim: izstāde no 6. novembra līdz 4. decembrim 1927 Rīgas pilsētas Mākslas muzejā, katalogs [Simon Lissim: izstāde...katalogs]

1927

Teksts paralēli latviešu un franču valodā.

In situ quantification of the nitrogen content of olivine-hosted melt inclusions from Klyuchevskoy volcano (Kamchatka): Implications for nitrogen rec…

2021

International audience; Assessing the N content of arc magmas and their mantle source remains a challenge because the volatile element composition of melts and gases can be modified during magma ascent, storage, and eruption. Given that melt inclusions (MIs) in Mg-rich olivine represent the best proxies for primary arc melts, we applied, for the first time, an in situ high-resolution secondary ion mass spectrometry (SIMS) method to determine the N concentration in olivine-hosted MIs from Klyuchevskoy volcano in Kamchatka. To reverse the effects of post-entrapment modification processes (i.e., exsolution of volatiles into a fluid bubble), the MIs were partially to completely homogenized at h…

Indagini preliminari ToF-SIMS su manufatti lignei provenienti dal museo diocesano di Palermo

2007

The Time of Flight Secondary Ion Mass Spectrometry (ToF-SIMS) is a methodology only recently applied to the study of the artworks. This tecnique allow the acquisition of a high amount of morphological and chemical information, directly related to the surface properties of the investigated sample. Through this technique it is possible to carry out an elemental analysis of the material as well as a determination of molecular ions (organic and/or inorganic) with a molecular weight ≤ 5000 Dalton (atomic mass unit). Moreover it is possible to use this spectrometry in an Imaging mode, that supplies a spatial distribution of the present substances, by the generation of "a chemical image", with a v…

Analisi di manufatti lignei provenienti dal Museo Diocesano di Palermo tramite Spettrometria di massa ToF-SIMS

2006

Vēstures un filoloģijas zinātnes, 1. sērija

1956

Influence of post-treatment time of trivalent chromium protection coating on aluminium alloy 2024-T3 on improved corrosion resistance

2019

Abstract Low corrosion protection performances of Trivalent Chromium Process (TCP) coatings with reference to Chromium Conversion Coatings (CCC) deposited on aluminium alloys can be overcome by application of post-treatment processes. This work shows the effect of post-treatment bath (containing hydrogen peroxide and lanthanum salt) on the chemical composition, structure and the corrosion performances of TCP coating deposited on AA 2024-T3 aluminium alloy. Different times of post-treatment bath were applied on the TCP coating and the samples were analyzed by Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS), X-ray Photoelectron Spectroscopy (XPS) and Glow Discharge-Optical Emission …