A multi-wavelength study of SXP 1062, the long period X-ray pulsar associated with a supernova remnant

SXP 1062 is a Be X-ray binary located in the Small Magellanic Cloud. It hosts a long-period X-ray pulsar and is likely associated with the supernova remnant MCSNR J0127-7332. In this work we present a multi-wavelength view on SXP 1062 in different luminosity regimes. We consider monitoring campaigns in optical (OGLE survey) and X-ray (SWIFT telescope). During these campaigns a tight coincidence of X-ray and optical outbursts is observed. We interpret this as typical Type I outbursts as often detected in Be X-ray binaries at periastron passage of the neutron star. To study different X-ray luminosity regimes in depth, during the source quiescence we observed it with XMM-Newton while Chandra observations followed an X-ray outburst. Nearly simultaneously with Chandra observations in X-rays, in optical the RSS/SALT telescope obtained spectra of SXP 1062. On the basis of our multi-wavelength campaign we propose a simple scenario where the disc of the Be star is observed face-on, while the orbit of the neutron star is inclined with respect to the disc. According to the model of quasi-spherical settling accretion our estimation of the magnetic field of the pulsar in SXP 1062 does not require an extremely strong magnetic field at the present time.Comment: accepted for publication in MNRA

Carbohydrates as enantioinduction components in stereoselective catalysis

Carbohydrate derivatives are readily available chiral molecules, yet they are infrequently employed as enantioinduction components in stereoselective catalysis. In this review, synthetic approaches to carbohydrate-based ligands and catalysts are outlined, along with example applications in enantioselective catalysis. A wide range of carbohydrate-based functionality is covered, and key trends and future opportunities are identified

Stereoselective synthesis of glycosides using (salen)Co catalysts as promoters

The use of (salen)Co catalysts as a new class of bench-stable stereoselective glycosylation promoters of trichloroacetimidate glycosyl donors at room temperature is described.</p

The nitrogen cycle in the Seine and Scheldt estuaries

The Seine and Scheldt estuaries are both located in the same geographical area and they represent important tributaries of the North Sea. Due to their high population density and large agricultural areas, the Seine and Scheldt estuaries receive extremely high nitrogen loads, mainly originating from wastewater and land fertilisers. The way this nitrogen is transformed in the system and exported to the North Sea depends on the characteristics of each system. The Seine and Scheldt estuaries are the outlet of river systems with respectively 78600 km² and 21500 km² watershed area, 420 and 108 m³/s average discharge, 46 and 40 % of agriculture area, and 195 and 425 inh./km² population density. Major difference between the estuaries lays in their hydrological characteristics. While the Seine estuary is typically channelled over most of its length with very reduced intertidal areas and short residence times (in the order of 1 week on the average), the Scheldt estuary has a typical funnel shape with large intertidal areas and long residence times (in the order of 1 month). The influence of these characteristics on major N-transformation processes (inorganic N assimilation by plankton, organic N mineralisation, nitrification, and denitrification) is presented and discussed, and the importance of both estuaries as sources of N for the North Sea is be evaluated

Production of belite calcium sulfoaluminate cement using sulfur as a fuel and as a source of clinker sulfur trioxide : pilot kiln trial

The authors gratefully acknowledge the financial support provided by the Gulf Organization for Research and Development (GORD), Qatar, through research grant number ENG016RGG11757. The authors would also like to acknowledge Thomas Matschei and Guanshu Li for the stimulating and fruitful discussions concerning the development of this work. The continuous support prior to, during and after the pilot kiln trial from Vadym Kuznietsov and the entire team at IBU-tec is also greatly appreciated.Peer reviewedPublisher PD