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Volcanic gas plumes’ effect on the spectrum of Venus
Get PDFVenus is home to thousands of volcanoes, with a wide range of volumes and sizes. Its surface is relatively young, with a temperature of approximately 735 K and an atmosphere of 92 bar. Past and possible ongoing volcanic outgassing is expected to provide a source to the sustenance of this massive atmosphere, dominated by CO2 and SO2. The lower atmosphere can be investigated in the near-infrared transparency windows on the nightside, such as the 2.3μm thermal emission window, which provides a chance of detection of species with volcanic origin, such as water vapor. The Planetary Spectrum Generator was used to simulate the nightside 2.3μm thermal emission window of Venus. We simulated the effect of a volcanic gas plume rising to a ceiling altitude, for species such as H2O, CO, OCS, HF and SO2. The sensitivity of the radiance spectrum at different wavelengths was explored as an attempt to qualitatively access detection for future measurements of both ground-based and space-instrumentation. We conclude from our qualitative analysis that for the H2O, CO and OCS plumes simulated there is potential to achieve a detection in the future, given a minimum required signal-to-noise ratio of 50. For SO2 and HF plumes, a higher signal-to-noise ratio would be needed
"Het niet alledaagsche der toestanden" Dagboeken uit de Tweede Wereldoorlog als historische bron
Get PDFThis article discusses war diaries from World War II as historical sources and sheds light on their value for social historians. First, we discuss the importance of a good policy in terms of preservation and accessibility of the war diaries. Next, we situate war diaries as a specific genre within ego documents. We then show how war diaries can contribute to the historiography, using examples from the existing literature. Throughout the article, we draw from thirty Belgian war diaries to illustrate their potential uses. These war diaries were found in judicial files of collaboration cases.The full text of the article can be downloaded here as PDF. Open access licensed under CC BY. Use permitted with attribution. Copyright (c) 2025 Laura Nys, Bart Willems.(PDF) NYS & WILLEMS - "Het niet alledaagsche der toestanden" Dagboeken uit de Tweede Wereldoorlog als historische bron</a
Inventaire des archives de la commune de Mellet : Dépôt 2019 (1794-1976 (1991))
Get PDFAu cœur du Hainaut, la commune de Mellet raconte plus de deux siècles d’histoire locale, de la période française à la fusion des Bons Villers en 1977. Village agricole célèbre pour ses carottes et sa chicorée, berceau du saint Mutien-Marie, Mellet reflète la vitalité du monde rural wallon. Ses archives (1794-1991), désormais conservées aux Archives de l’État à Mons, dévoilent la vie communale dans toute sa richesse : politique, économie, enseignement, religion et bienfaisance. Fruit du projet « Archives locales de Wallonie », cet inventaire offre aux chercheurs et passionnés un regard vivant sur la mémoire démocratique et sociale du Hainaut.The records described in this inventory are held at the State Archives in Mons (inventory code 524 - AEM.01.322).This inventory is the fixed published version dated 10-01-2025. For the dynamic inventory under active revision, including recent updates and additions, please consult our online search platform AGATHA. In AGATHA, you can also request the archival items you wish to consult in the reading room
Evidence of an enhanced near-surface ozone layer at tropical latitudes on Mars
No full textOzone plays a key role in both atmospheric and near-surface chemistry, as well as in UV absorption in planetary atmospheres. Here, we report observations of ozone from the surface of another planet, using the ozone detector included in the Mars Environmental Dynamics Analyzer (MEDA) Radiation and Dust Sensor (RDS) aboard NASA’s Mars 2020 mission, complementing previous space-based and ground-based observations from Earth. Measurements were acquired at Jezero Crater, Mars, at midday, retrieving an average ozone column abundance of 3.8 ± 2.3 μm-atm (1σ) around aphelion, which fell below uncertainties in northern summer. The retrieved column abundance is in reasonable agreement with previous space-based and ground-based observations from Earth. The measurements of total ozone column abundance around aphelion from Mars 2020 and other missions, together with vertical profile observations from orbit, indicate that ~90% of the observed ozone is confined below 20 km of altitude, the aphelion layer weakly contributing to the total column abundance. These ozone levels below 20 km are 3 to 4 times higher than those predicted by models, challenging current understanding of atmospheric chemistry and composition in the lower atmosphere of Mars. It may be possible that aerosols are reducing the destruction pathways of ozone and/or that unknown active chemistry in the near-surface atmosphere of Mars is at work. Both cases should strongly modify the oxidizing capacity in the lower atmosphere of Mars from current model predictions
Aperçu nouveaux inventaires et instruments de recherche Archives de l'État en Belgique - Octobre 2025
No full textMonthly overview of new inventories and finding aids: October 2025
Inventaris van de archieven van de krijgsauditoraten en de krijgsraden te velde, actief bij het Belgische leger gedurende de mobilisatieperiode, de achttiendaagse veldtocht en in Zuid-Frankrijk tijdens WOII (1939-1940 (1942))
No full textDit archiefbestand dompelt je onder in het zenuwcentrum van het Belgische leger in 1939-1940. Krijgsauditoraten en krijgsraden te velde proberen discipline te bewaren tijdens mobilisatie, achttiendaagse veldtocht en terugtocht naar Zuid-Frankrijk. In dossiers over desertie, geweld, diefstal en spanningen met de burgerbevolking zie je het front- én achterlijnleven van soldaten, officieren en jonge CRAB-rekruten.
De stukken zelf hebben een ware odyssee achter de rug: haastig geëvacueerd, door de Duitsers geroofd, via Berlijn in het Moskouse Osoboy-archief beland en pas recent gerepatrieerd. Deze inventaris bundelt en ontsluit 15 meter cruciale bronnen voor nieuw onderzoek naar oorlog, recht en legerdiscipline.The records described in this inventory are held at the National Archives 2 - Joseph Cuvelier repository (inventory code 545 - I 83).This inventory is the fixed published version dated 21-12-2025. For the dynamic inventory under active revision, including recent updates and additions, please consult our online search platform AGATHA. In AGATHA, you can also request the archival items you wish to consult in the reading room
(Re)chercher les archives relatives aux métis et à leur histoire familiale : Jalon de recherche (2e édition, revue et corrigée)
No full textDepuis 2019, les Archives générales du Royaume retracent l’histoire des métis issus de la colonisation belge au Congo, au Rwanda et au Burundi. Cette deuxième édition revue et enrichie du jalon de recherche (Re)chercher les archives relatives aux métis et à leur histoire familiale offre un accès unique aux archives publiques et privées documentant leurs parcours, leurs séparations et leurs quêtes d’identité. Fruit du projet Résolution-Métis, elle rassemble des sources inédites et des clés de lecture pour comprendre ce passé complexe. Plus qu’un outil de recherche, c’est un pont entre mémoire et histoire, au service de celles et ceux qui cherchent leurs racines et une vérité partagée.The full text can also be downloaded here as PDF. Open Access licensed under CC BY-NC-ND. Use permitted for non-commercial purposes with attribution. No derivatives.(PDF) (Re)chercher les archives relatives aux métis et à leur histoire familiale: Jalon de recherche (2e édition, revue et corrigée)This second edition replaces the first edition of 2023: Lauwers, D., & Rovetta, O. (Eds.). (2023). (Re)chercher les archives relatives aux métis et à leur histoire familiale: Jalon de recherche. (Jalons de recherche 48; Publication 6366). State Archives of Belgium
Inventaris van het archief van de balie te Brussel en aanverwante archiefvormers 1811 − 1989 (vnl. 1811 − 1964)
No full textDe balie van Brussel behoort al twee eeuwen tot de machtigste spelers in het Belgische rechtsleven. Deze inventaris ontsluit 36,5 strekkende meter archief van de Orde van Advocaten en aanverwante organisaties (Conférence du Jeune Barreau, Vlaams Pleitgenootschap, Union internationale des Avocats, enz.). Notulen, correspondentie, tuchtdossiers en dossiers over taalwetgeving, sekwesters, gratis rechtsbijstand en de relatie tussen balie, politiek en zakenwereld tonen hoe de advocatuur mee vorm gaf aan Napoleontische hervormingen, Belgische Revolutie, twee wereldoorlogen, “crise du barreau” en communautaire breuk. Een onmisbaar instrument voor ieder die de Brusselse balie en de evolutie van de Belgische rechtsstaat wil begrijpen.The records described in this inventory are held at the State Archives in Brussels (inventory code 541 – I 102).This inventory is the frozen published version dated 09-12-2025. For the dynamic inventory under active revision, including recent updates and additions, please consult our online search platform AGATHA. In AGATHA you can also place requests for the archival items you want to view in the reading room
Halving the Barrier to Gas-Phase Oxidation of Bromide by Ozone
No full textRecent atmospheric measurements indicate that bromine and iodine may be responsible for up to 72% of halogen-induced ozone loss near the tropopause, yet there is ongoing uncertainty regarding the multiphase chemistry of bromide and iodide anions in ozone depletion. Here, we demonstrate the unequivocal ozone-dependence of the archetype 1Br– + 1O3 reaction, which proceeds with an experimental rate constant of 8.9 (±4.4) × 10–15 cm3 molecule–1 s–1. The reaction mechanism is revised to proceed via a singlet transition state with a rate-limiting barrier of +22.1 kJ mol–1 −half that of prior estimates −prior to facile spin-crossing to yield 1BrO– + 3O2. Statistical rate modeling using this new barrier height predicts a rate constant of 5.7 × 10–15 cm3 molecule–1 s–1, which is in excellent agreement with the experiment. This reconciliation of the kinetics for the intrinsic gas-phase reaction will enable systematic evaluation of temperature, pressure, and solvation effects on this ion–molecule chemistry and thus inform the impact of halide anion chemistry on atmospheric ozone
Simultaneous observations of atmospheric IO radical, O3, and sea surface iodide over the tropical western Pacific warm pool: strong correlation of IO levels with estimated inorganic iodine fluxes
No full textWe conducted intensive atmospheric observations and surface seawater sampling in the western tropical Pacific aboard R/V Mirai during the MR21-03 cruise from May to July 2021 to investigate iodine variations and photochemistry over the global sea surface temperature (SST) maxima (warm pool). Consistent with previous studies, high near-surface atmospheric iodine monoxide (IO) mixing ratios of up to ~ 1 pptv were observed. A strong positive correlation (r = 0.95) was found between the IO mixing ratios and inorganic iodine flux calculated from atmospheric ozone (O3) and sea surface I– data, indicating that the assumed emission flux and the associated processes are qualitatively reasonable for the studied warm pool region. This study provided the first simultaneous observations of atmospheric O3, IO, and sea surface I– over the warm pool, thus demonstrating the robust nature of the relationship. The CHASER chemical transport model satisfactorily reproduced the observed positive correlation. The model overestimated the IO levels by 40%, but large systematic uncertainties were associated; refining the assumed emission flux and parameters used in the model is recommended for more quantitative comparisons. The collective findings underscore the significance of concurrent observations of atmospheric O3, IO, and sea surface iodide for elucidating ocean–atmosphere processes involving reactive iodine compounds