Carbon-rich dust is known to form in the atmosphere of the semiregular variable star R Sculptoris. Such stardust, as well as the molecules and gas produced during the lifetime of the star, will be spread into the Galaxy via the mass-loss process. Probing this process is crucial to understand the chemical enrichment of the Galaxy. R Scl was observed using the ESO/VLTI MATISSE instrument in December 2018. Here we show the first images of the star between 3 and 10 R*. Using the complementary MIRA 3D image reconstruction and the RHAPSODY 1D intensity profile reconstruction code, we reveal the location of molecules and dust in the close environment of the star. Indeed, the C2H2 and HCN molecules are spatially located between 1 and 3.4 R* which is much closer to the star than the location of the dust. The R Scl spectrum is fitted by molecules and a dust mixture of 90% of amorphous carbon and 10% of silicone carbide. The inner boundary of the dust envelope is estimated by DUSTY at about 4.6 R*. We derive a mass-loss rate of 1.2 ± 0.4 × 10−6M⊙ yr−1however no clear SiC forming region has been detected in the MATISSE data.

The literature contains considerable disagreements on the relative stabilities of the members of the copper hydroxyl sulphate family. Titration of copper sulphate with sodium hydroxide is claimed by some to produce only brochantite, while other reports indicate that antlerite and a dihydrate of antlerite are produced in the titration. Most stability field diagrams show that antlerite is the more stable stoichiomer at pH 4 and sulphate activity of 0.05–1. We have reexamined this stoichiometric family by titration of aqueous copper sulphate with sodiumhydroxide and sodium carbonate, reverse titration of sodiumhydroxide with copper sulphate and simultaneous addition of copper sulphate and sodium hydroxide at a variety of mole ratios, concentrations, temperatures and reaction times. We have also explored the reaction of copper hydroxide with copper sulphate and the reaction of weak bases, such as sodiumacetate, sodiumcarbonate and urea, with copper sulphate. Our work indicates that: (1) antlerite is not formed in reactions of 0.05 to 1.2 M CuSO4 with 0.05–1.0 M NaOH or Na2CO3 at room temperature; (2) antlerite is formed in the addition of small concentrations of base (≤0.01 M) to 1 M CuSO4 at 80°C, but not at roomtem perature or with 0.01 M CuSO4 at 80°C; (3) the formation of Cu5(SO4)2(OH)6·4H2O occurs at large Cu2+ to base mole ratios; (4) the compound described in the literature as antlerite dihydrate is actually Cu5(SO4)2(OH)6.4H2O; (5) at mole ratios of Cu2+ to OH– ranging from 2:1 to 1:2 the predominant product is brochantite; and (6) brochantite and Cu5(SO4)2(OH)6.4H2O are converted to antlerite in the presence of 1 M CuSO4 (the latter requires temperatures of 80°C or greater).

The Ksp (ion activity product) values of antlerite and brochantite were determined to be 2.53 (0.01)⨯10−48 and 1.01 (0.01)⨯10−69, respectively, using atomic absorption spectroscopy and Visual MINTEQ after equilibration in solutions of varying ionic strength and pH for six days. These values are in good agreement with those from the literature. However, after 6 months, antlerite in contact with solution is partially converted to brochantite and hence is metastable with a relatively low conversion rate. The Ksp value for antlerite must therefore be considered approximate. The relative stabilities of the copper hydroxyl sulphates are rationalized using appropriate equations and Gibbs energy calculations. A Gibbs free energy of formation for Cu5(SO4)2(OH)6.4H2O of –3442 kJ/mol was obtained from the simple salt approximation.

Elemental, chemical, and structural analysis of polycrystalline materials at the micron scale is frequently carried out using microfocused synchrotron X-ray beams, sometimes on multiple instruments. The Maia pixelated energy-dispersive X-ray area detector enables the simultaneous collection of X-ray fluorescence (XRF) and diffraction because of the relatively large solid angle and number of pixels when compared with other systems. The large solid angle also permits extraction of surface topography because of changes in self-absorption. This work demonstrates the capability of the Maia detector for simultaneous measurement of XRF and diffraction for mapping the short- and long-range order across the grain structure in a Ni polycrystalline foil.

A new generation of solar instruments provides improved spectral, spatial, and temporal resolution, thus facilitating a better understanding of dynamic processes on the Sun. High-resolution observations often reveal multiple-component spectral line profiles, e.g., in the near-infrared He i 10830 Å triplet, which provides information about the chromospheric velocity and magnetic fine structure. We observed an emerging flux region, including two small pores and an arch filament system, on 2015 April 17 with the ‘very fast spectroscopic mode’ of the GREGOR Infrared Spectrograph (GRIS) situated at the 1.5-meter GREGOR solar telescope at Observatorio del Teide, Tenerife, Spain. We discuss this method of obtaining fast (one per minute) spectral scans of the solar surface and its potential to follow dynamic processes on the Sun. We demonstrate the performance of the ‘very fast spectroscopic mode’ by tracking chromospheric high-velocity features in the arch filament system.

In a particular success for translational research agendas, characterization of the neuronal circuits underlying fear extinction, and basic research in animal extinction paradigms, has led to intervention studies examining the use of D-cycloserine (DCS) to enhance therapeutic learning from exposure-based cognitive-behavioral therapy (CBT). In this article, we review these intervention studies, and discuss DCS augmentation of CBT relative to more traditional combination-treatment strategies in the treatment of anxiety disorders. We offer an accounting, based on evidence for internal context effects, of current limitations in the combination of antidepressant or benzodiazepine medications with CBT and discuss the advantages of isolated-dosing strategies with DCS relative to these limitations. This strategy is contrasted with the chronic-dosing applications of DCS for schizophrenia and Alzheimer's disease, and future directions for isolated-dosing strategies are discussed.

A modified critical point model dielectric function for graphene is derived here and used to analyze spectroscopic ellipsometry data obtained over a wide spectral range from 3 to 9 eV. Critical point and exciton resonance energies are extracted and discussed. Our findings indicate that epitaxial graphene on SiC to exhibits equivalent exciton behavior to that of suspended graphene. We further apply our model dielectric function to evaluate dielectric function data for highly oriented pyrolytic graphite reported in the literature. Excellent agreement is found between the critical point model developed here and the literature data even for the low energy spectral range up to 1 eV.

Four matrix-phase crystallographic directions of IN718 are investigated by in situ tensile tests using neutron diffraction. The elastic diffraction constants for all directions measured are compared to theoretical values calculated by the Kröner model. The differences between the microscopic and the macroscopic material response are given. The accumulation of microstrains in the different crystallographic directions is discussed. A comparison between the results of a single phase material (ingot IN718) and two differently thermal treated multiphase materials is presented.

The early Neolithic in northern Central Europe ought to be the theatre in which incoming farmers meet local hunter-gatherers, with greater or lesser impact. By way of contrast, the authors use isotope analysis in a cemetery beside the Danube to describe a peaceful, well-integrated community with a common diet and largely indigenous inhabitants. Men and women may have had different mobility strategies, but the isotopes did not signal special origins or diverse food-producing roles. Other explanations attend the variations in the burial rites of individuals and their distribution into cemetery plots.

Although predictions suggest that ocean acidification will significantly impact polar oceans within 20–30 years, there is limited information regarding present-day pH dynamics of the Southern Ocean. Here, we present novel high-frequency observations of pH collected during spring of 2010 using SeaFET pH sensors at three locations under fast sea ice in the southern Ross Sea. During these deployments in McMurdo Sound, baseline pH ranged between 8.019–8.045, with low to moderate overall variation (0.043–0.114 units) on the scale of hours to days. The variation was predominantly in the direction of increased pH relative to baseline observations. Estimates of aragonite saturation state (ΩAr) were > 1 with no observations of subsaturation. Time series records such as these are significant to the Antarctic science community; this information can be leveraged towards framing more environmentally relevant laboratory experiments aimed at assessing the vulnerability of Antarctic species to ocean acidification. In addition, increased spatial and temporal coverage of pH datasets may reveal ecologically significant patterns. Specifically, whether such variation in natural ocean pH dynamics may drive local adaptation to pH variation or provide refugia for populations of marine calcifiers in a future, acidifying ocean.

One of the multiple capabilities of the new Joint Engineering, Environmental and Processing (JEEP) beamline I12 at Diamond Light Source is the set-up for polychromatic high-energy X-ray diffraction for the study of polycrystalline deformation and residual stresses. The results and interpretation of the first experiments carried out on JEEP are reported. Energy dispersive diffraction patterns from titanium alloy Ti-6Al-4V were collected using the new 23-cell ‘horseshoe’ detector and interpreted using Pawley refinement to determine the residual elastic strains at the macro- and meso-scale. It provides a clear demonstration of the tensile-compressive hardening asymmetry of the hexagonal close-packed grains oriented with the basal plane perpendicular to the loading direction.

This paper gives an overview on the standard crystalline silicon solar cell manufacturing processes typically applied in industry. Main focus has been put on plasma processes which can replace existing, mainly wet chemical processes within the standard process flow. Finally, additional plasma processes are presented which are suited for higher-efficient solar cells, i.e. for the “passivated emitter and rear cell” concept (PERC) or the “heterojunction with intrinsic thin layer” approach (HIT). Plasma processes for the deposition of thin dielectric or semiconducting layers for surface passivation, emitter deposition or anti-reflective coating purposes are presented. Plasma etching processes for the removal of phosphorus silicate glass or parasitic emitters, for wafer cleaning and masked and mask-free surface texturisation are discussed.

Congenital arteriovenous malformations are rare causes of congestive cardiac failure in neonates. The most common sites are in the head and liver, but other sites include the thorax, the abdomen and the limbs. The onset of failure is usually not in the immediate neonatal period, but later on in life, albeit that lesions such as the arteriovenous malformation of the vein of Galen, and other arteriovenous malformations in different locations which produce high flow can present early. We describe here the first case, to the best of our knowledge, of prenatal detection of an intrathoracic arteriovenous malformation producing neonatal cardiac failure, which was successfully treated by surgery postnatally.