Sulfur loss from subducted altered oceanic crust and implications for mantle oxidation

© The Author(s), [year]. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Walters, J. B., Cruz-Uribe, A. M., & Marschall, H. R. Sulfur loss from subducted altered oceanic crust and implications for mantle oxidation. Geochemical Perspectives Letters, 13, (2020): 36-41, doi:10.7185/geochemlet.2011.Oxygen fugacity (fO2) is a controlling factor of the physics of Earth’s mantle; however, the mechanisms driving spatial and secular changes in fO2 associated with convergent margins are highly debated. We present new thermodynamic models and petrographic observations to predict that oxidised sulfur species are produced during the subduction of altered oceanic crust. Sulfur loss from the subducting slab is a function of the protolith Fe3+/ΣFe ratio and subduction zone thermal structure, with elevated sulfur fluxes predicted for oxidised slabs in cold subduction zones. We also predict bi-modal release of sulfur-bearing fluids, with a low volume shallow flux of reduced sulfur followed by an enhanced deep flux of sulfate and sulfite species, consistent with oxidised arc magmas and associated copper porphyry deposits. The variable SOx release predicted by our models both across and among active margins may introduce fO2 heterogeneity to the upper mantle.We thank James Connolly for modelling support and Peter van Keken for providing updated P–T paths for the Syracuse et al. (2010) models. The manuscript benefited from the editorial handling by Helen Williams and from constructive reviews of Maryjo Brounce, Katy Evans, and an anonymous reviewer. JBW acknowledges Fulbright and Chase Distinguished Research fellowships. This work was supported by NSF grant EAR1725301 awarded to AMC

Microscopic calculations of collective flow probing the short-range nature of the nuclear force

Collisions between two nuclei have been modeled by numerical solution of classical approximations to the equations of motion of the constituent nucleons. For the reaction Nb(400 MeV/u)+Nb, a correlated sidewards emission of nucleons is observed. This is attributed to the repulsive short-range component of the nucleon-nucleon potential. A strong dependence of the flow angle on the impact parameter is observed, in accord with recent experimental results

EPR effect in gravitational field: nature of non-locality

The realization of the Einstein-Podolsky-Rosen effect by the correlation of spin projections of two particles created in the decay of a single scalar particle is considered for particles propagating in gravitational field. The absence of a global definition of spatial directions makes it unclear whether the correlation may exist in this case and, if yes, what directions in distant regions must be correlated. It is shown that in a gravitational field an approximate correlation may exist and the correlated directions are connected with each other by the parallel transport along the world lines of the particles. The reason for this is that the actual origin of the quantum non-locality is founded in local processes.Comment: 12 pages, LATE

Broadband modelling of short gamma-ray bursts with energy injection from magnetar spin-down and its implications for radio detectability

The magnetar model has been proposed to explain the apparent energy injection in the X-ray light curves of short gamma-ray bursts (SGRBs), but its implications across the full broadband spectrum are not well explored. We investigate the broadband modelling of four SGRBs with evidence for energy injection in their X-ray light curves, applying a physically motivated model in which a newly formed magnetar injects energy into a forward shock as it loses angular momentum along open field lines. By performing an order of magnitude search for the underlying physical parameters in the blast wave, we constrain the characteristic break frequencies of the synchrotron spectrum against their manifestations in the available multi-wavelength observations for each burst. The application of the magnetar energy injection profile restricts the successful matches to a limited family of models that are self-consistent within the magnetic dipole spin-down framework.We produce synthetic light curves that describe how the radio signatures of these SGRBs ought to have looked given the restrictions imposed by the available data, and discuss the detectability of these signatures with present-day and near-future radio telescopes. Our results show that both the Atacama Large Millimetre Array and the upgraded Very Large Array are now sensitive enough to detect the radio signature within two weeks of trigger in most SGRBs, assuming our sample is representative of the population as a whole. We also find that the upcoming Square Kilometre Array will be sensitive to depths greater than those of our lower limit predictions.Comment: 15 pages, 4 figures, 6 tables, accepted for publication in MNRA

Considerations on Sampling and Statistical Analysis in Grassland Ensiling Trials

Critical findings on design, statistical analysis, and interpretation of the results will be addressed based on comparative ensiling trials. For this aim, a lab-scale ensiling trial on biostatistical issues was conducted in 2021. Grass material from a permanent mowing pasture was taken from (i) 10 sampling points, (ii) one sampling point, (iii) a mixture of 10 sampling points. For each sub-trial (based on the sampling design), 3 levels of the fixed treatment factor silage additive were tested with 10 replicates (without additive, chemical silage additive, biological silage additive). The analysis was performed within a linear mixed effects model (LMM) as randomized complete block design (RCBD), accounting for systematic effects of field sampling points (i) and/or time processing (i, ii, iii). In sub- trial (i), variability in trait values was highest and more influenced by treatments (variance heterogeneity), and block effects were most pronounced. In contrast, the block effect was less pronounced in (ii) and (iii), and we could not find a time gradient in the silage trait values. Depending on the nature of the silage trait (distribution, treatment variances), a suitable analysis procedure has to be chosen. The frequently used low number of replications is probably not sufficient

Transport model analysis of particle correlations in relativistic heavy ion collisions at femtometer scales

The pion source as seen through HBT correlations at RHIC energies is investigated within the UrQMD approach. We find that the calculated transverse momentum, centrality, and system size dependence of the Pratt-HBT radii $R_L$ and $R_S$ are reasonably well in line with experimental data. The predicted $R_O$ values in central heavy ion collisions are larger as compared to experimental data. The corresponding quantity $\sqrt{R_O^{2}-R_S^{2}}$ of the pion emission source is somewhat larger than experimental estimates.Comment: 12 pages, 5 figures, to be published in PR

Innovation in the European chemical industry

Firms in the European chemical industry have been among the most successful firms world wide. However, they have had to undertake severe restucturing in order to maintain their market position. These efforts focused in particular on strengthening their innovative capability as product and process innovation have become the most decisive factors in global competition. In order to improve the innovative conditions, the European Commission has supported the Community Innovation Survey (CIS). 1992/1993 was the first time that large-scale harmonised innovation surveys were carried out in all Member States of the European Union. This study uses the CIS micro data from nearly 2000 European chemical firms. This study focuses on the identification of innovative trends within the chemical industry between 1984 and 1993. Using data from annual reports of nine selected European stock companies, the study identifies those areas of the chemical industry currently having the highest innovative potential. Three speciality categories are identified as having the highest number of innovations during this ten year period: chemicals, paints/varnishes, and plastics. -- Obwohl viele europäische Unternehmen der chemischen Industrie in den vergangenen Jahrzehnten zu den erfolgreichsten in der Welt zählten, mußten sie sich Anfang der neunziger Jahre einem gravierenden Strukturwandel unterziehen, um ihre Position behaupten zu können. Die Fähigkeit der Unternehmen, Innovationen hervorzubringen, stand und steht dabei im Mittelpunkt. Mit dem Ziel, die Rahmenbedingungen für Innovationen zu verbessern, führte die EU-Kommission 1993 eine europaweite Innovationserhebung, den Community Innovation Survey (CIS) durch. In dieser Studie wurden die anonymisierten Antworten von nahezu 2000 Unternehmen der chemischen Industrie analysiert. Um Innovationstrends aufzuzeigen zu können, wurden darüber hinaus Geschäftsberichte von neun großen europäischen Chemieunternehmen ausgewertet. So wurden die Sparten Spezialitäten, Farben/Lacke und Kunststoffe als diejenigen Sparten identifiziert, die im Untersuchungszeitraum (1984-1993) die meisten Innovationen aufwiesen.

Constraining properties of GRB magnetar central engines using the observed plateau luminosity and duration correlation

An intrinsic correlation has been identified between the luminosity and duration of plateaus in the X-ray afterglows of Gamma-Ray Bursts (GRBs; Dainotti et al. 2008), suggesting a central engine origin. The magnetar central engine model predicts an observable plateau phase, with plateau durations and luminosities being determined by the magnetic fields and spin periods of the newly formed magnetar. This paper analytically shows that the magnetar central engine model can explain, within the 1$\sigma$ uncertainties, the correlation between plateau luminosity and duration. The observed scatter in the correlation most likely originates in the spread of initial spin periods of the newly formed magnetar and provides an estimate of the maximum spin period of ~35 ms (assuming a constant mass, efficiency and beaming across the GRB sample). Additionally, by combining the observed data and simulations, we show that the magnetar emission is most likely narrowly beamed and has $\lesssim$20% efficiency in conversion of rotational energy from the magnetar into the observed plateau luminosity. The beaming angles and efficiencies obtained by this method are fully consistent with both predicted and observed values. We find that Short GRBs and Short GRBs with Extended Emission lie on the same correlation but are statistically inconsistent with being drawn from the same distribution as Long GRBs, this is consistent with them having a wider beaming angle than Long GRBs.Comment: MNRAS Accepte