On the acid disulphate (pyrosulphate) of nitrosyle

Crystallized HS2O7NO was obtained by reacting excess NO2 gas with liquid HSO3Cl. Stable to a melting point of approximately 105 deg, this reacted with nitrates from about 25 deg and formed M2S2O7, with an acid disulphate intermediary. Excess NO2, whether liquid or gas, reacted with HS2O7NO to five (NO)2S2O7

Industrial experiences with resource management under software randomization in ARINC653 avionics environments

Injecting randomization in different layers of the computing platform has been shown beneficial for security, resilience to software bugs and timing analysis. In this paper, with focus on the latter, we show our experience regarding memory and timing resource management when software randomization techniques are applied to one of the most stringent industrial environments, ARINC653-based avionics. We describe the challenges in this task, we propose a set of solutions and present the results obtained for two commercial avionics applications, executed on COTS hardware and RTOS.The work leading to these results has been funded by the European Community’s Seventh Framework Programme (FP7/2007-2013) un- der the PROXIMA Project (grant agreement 611085). Moreover, it has been partially supported by the Spanish Ministry of Science and Innovation under grant TIN2015-65316-P and the HiPEAC Network of Excellence.Peer ReviewedPostprint (published version

STT-MRAM for real-time embedded systems: performance and WCET implications

STT-MRAM is an emerging non-volatile memory quickly approaching DRAM in terms of capacity, frequency and device size. Intensified efforts in STT-MRAM research by the memory manufacturers may indicate a revolution with STT-MRAM memory technology is imminent, and therefore it is essential to perform system level research to explore use-cases and identify computing domains that could benefit from this technology. Special STT-MRAM features such as intrinsic radiation hardness, non-volatility, zero stand-by power and capability to function in extreme temperatures makes it particularly suitable for aerospace, avionics and automotive applications. Such applications often have real-time requirements --- that is, certain tasks must complete within a strict deadline. Analyzing whether this deadline is met requires Worst Case Execution Time (WCET) Analysis, which is a fundamental part of evaluating any real-time system. In this study, we investigate the feasibility of using STT-MRAM in real-time embedded systems by analyzing average system performance impact and WCET implications.This work was supported by BSC, Spanish Government through Programa Severo Ochoa (SEV-2015-0493), by the Spanish Ministry of Science and Technology through TIN2015-65316-P project and by the Generalitat de Catalunya (contracts 2014-SGR-1051 and 2014-SGR-1272). This work has also received funding from the European Union’s Horizon 2020 research and innovation programme under ExaNoDe project (grant agreement No 671578). Jaume Abella was partially supported by the Ministry of Economy and Competitive-ness under Ramon y Cajal postdoctoral fellowship RYC-2013-14717.Peer ReviewedPostprint (author's final draft

Sediment transport around port development area in estuary

This study focuses on sediment transport and tidal exchange dynamics in the Scheldt estuary at Kruibeke (about 5 km upstream of the Antwerp Harbour, Belgium) in the late 1990s and early 2000s. The involved parameters are tidal cycle measurements of total suspended sediment concentrations and fluxes, tidal water elevation, flow velocities, river discharges and tidal discharges. The data show that the net tidal water discharge over a full tidal cycle ranges between 96 and 729 m3 s???1 for the period 1995-1998, and between 67 and 319 m3 s???1 for the period 2002-2005. In the vicinity of Kruibeke, though the measured depth-integrated flood flow velocity is over 10% stronger than that of the ebb current, the net mass transport is ebb oriented. The depth-integrated suspended sediment concentration reaches up to 829 g m???3 and 394 g m???3 for the periods 1995-1998 and 2002-2005 respectively. Sediment load was clearly higher for 1995-1998 than that of for 2002-2005. The sediment mass load versus tidal water discharge reveals a correlation with appreciated R2 values of 0.9 and 0.8 for the periods 1995-1998 and 2002-2005 respectively. Evaluation of the temporal relation between sediment mass load and tidal water volume for a tidal phase, ebb and flood respectively, shows some correlation. Comparison of freshwater discharge and estuary net sediment discharge reveals a net export of sediments out of the estuary in the vicinity of Kruibeke. Yet, this net transport of sediments has notably decreased in the course of time from 1995 to 2005. Quantification and computation of resuspension of bed sediments scoured by tidal currents and further dispersed and enhanced by particle de-flocculation and flocculation and resulted particle settling could help to understand sediment transport dynamics in the Scheldt estuary

Elimination of turbidity and bacterial contamination in natural water sources (Ubangi river, Central Africa)

Having access to a natural source of water of sufficiently high quality for human consumption has become a strategic concern for the entire world. In fact, drinking water resources in developing countries are almost non-existent, as they are overused or polluted by intense human activity. Our study aims to develop a natural filter that reduces turbidity and eliminates human pathogens. The process developed should be inexpensive and minimize the use of chemical reagents, and should not be labor intensive. In this context, horizontal sand filtration that uses the natural process of water purification occurring in an aquifer can be regarded as the most suitable water treatment process for developing countries.Disposer d’une source d’eau naturelle de bonne qualité, pour la consommation humaine, est devenu maintenant une préoccupation stratégique pour le monde entier. En effet, les ressources en eaux potables dans les pays en voie de développement sont quasi-inexistantes, car surexploitées ou souillées par une activité humaine intense. L’étude que nous proposons a pour objectif : de mettre au point un filtre naturel qui diminue la turbidité et élimine les agents pathogènes pour l’homme. Le procédé développé peu onéreux devra réduire au maximum l’utilisation de réactifs chimiques, et minimiser toutes interventions humaines. La filtration horizontale sur sable qui utilise le processus naturel de purification de l’eau se produisant dans une nappe aquifère, peut être considéré comme le procédé de traitement de l’eau le plus approprié aux pays en voie de développement et répond aux objectifs fixés.Disponer de una fuente de agua natural de buena calidad, apta para el consumo humano, se ha convertido actualmente en una preocupación estratégica en todo el mundo. En efecto, los recursos de agua potable en los países en vías de desarrollo son prácticamente inexistentes, por exceso de explotación o por contaminación a causa de una actividad humana intensa.El estudio que proponemos tiene por objetivo: desarrollar un filtro natural que reduzca la turbidez y elimine los agentes patógenos perjudiciales para el hombre. El procedimiento desarrollado, de bajo coste, debería reducir al máximo el uso de sustancias químicas reactivas y minimizar cualquier intervención humana. Como la filtración horizontal sobre arena que utiliza el proceso natural de purificación del agua tiene lugar en una capa acuífera, se puede considerar como el procedimiento de tratamiento del agua más adecuado a los países en vías de desarrollo y responde a los objetivos fijados

Mud Origin, Characterisation and Human Activities (MOCHA): Final report

The cohesive sediments, which are frequently found in the Belgian nearshore zone (southern North Sea), are of different age such as tertiary clays and Holocene, modern and recently deposited muds. The area is characterised by a turbidity maximum. The source areas of the recently deposited muds and the effect of human impact vs. natural processes on the distribution and/or erosion of these sediments have been investigated using historic and recent bottom samples, in situ and remote sensing (satellite images) SPM concentration measurements, numerical modelling, GIS and clay mineral and microfossil analysis. The Schelde estuary, the potential erosion areas of cohesive sediments on the BCS and adjacent areas and the SPM transport through the Dover Strait have been considered as possible source areas.The historic bottom samples have been collected in the beginning of the 20th century, the quality of these samples and the meta-information is very high and they have proven to be a major reference to understand the evolution of the cohesive sediment distribution. The recent bottom samples consist of box core, Reineck core and Van Veen grab samples collected during the last 10 years. The processing of the historic and recent data on cohesive sediments was mainly based on field descriptions of the samples (consolidation, thickness) and morphological evolution. On some of the recent samples radioactive and gamma densitometric measurements have been carried out. During the processing the emphasis was put on the occurrence of thick layers (>30 cm) of freshly deposited to very soft consolidated mud and of clay and mud pebbles, because these sediments are witnesses of changes.Satellite images, in situ measurements and a 2D hydrodynamic numerical model have been combined to calculate the long term SPM transport through the Dover Strait and in the southern North Sea. The satellite images (SeaWiFS) provide synoptic views of SPM concentration. The representativness of SPM concentration maps derived from satellites for calculating long term transports has been investigated by comparing the SPM concentration variability from the in situ measurements with those of the satellite data. It is underlined that SPM concentration measurements should be carried out during at least one tidal cycle in high turbidity areas to obtain representative values of SPM concentration.Areas where the thickness of the Quaternary cover is less than 2.5 m were defined as potential erosion areas of Palaeogene clay containing deposits. In the framework of this project, the geological data related to the BCS have been reviewed and the relevant information was compiled into a GIS. This also included a small part of the French continental shelf. Additionally information was added from vibrocores analysis and Dutch geological data. Approximately 20 % of the BCS, 6 % of the small part of the French area and only 3% of the Dutch study area could possibly serve as a source for fine suspended sediments. Quaternary muds are mostly presented in the 2 eastern nearshore area; on the Dutch part they occur more offshore. Their occurrence represents 11% of the BCS and approximately 35% of the Rabsbank area Cretaceous microfossils are present in all samples and have been transported into the area with the residual water transport. Material from the east, in particular from the Eocene-Oligocene transitional strata, has been found in the eastern nearshore area up to about Oostende. This zone coincides with the extension of the Holocene mud and could indicate an erosion of these sediments and/or a transport of clay minerals from the Schelde estuary.Clay mineral analysis has been carried by two approaches in order to determine source areas. The results of the second approach show that no systematic differences in the clay mineralogy depending on geographic location could have been found within the samples. The results clearly prove the necessity of using more elaborate sample preparation procedures in examining the provenance of the mud deposits.Thick layers of fresh mud were deposited in the beginning of the 20th century mainly in a narrow band along the coast from about Nieuwpoort up to the mouth of the Westerschelde. These deposits were mainly the result of natural morphological changes. Today, most of the depositions of thick layers of fresh mud have been induced by anthropogenic operations, such as dumping, deepening of the navigation channels and construction and extension of the port of Zeebrugge. Comparing the actual situation with the situation 100 years ago reveals that the area around Zeebrugge where fresh mud is deposited extends more offshore today