The masses of compact objects like white dwarfs, neutron stars and black holes are fundamental to astrophysics, but very difficult to measure. We present the results of an analysis of subluminous B (sdB) stars in close binary systems with unseen compact companions to derive their masses and clarify their nature. Radial velocity curves were obtained from time resolved spectroscopy. The atmospher...

We give a brief review over the observational evidence for close substellar companions to hot subdwarf stars. The formation of these core helium-burning objects requires huge mass loss of their red giant progenitors. It has been suggested that besides stellar companions substellar objects in close orbits may be able to trigger this mass loss. Such objects can be easily detected around hot subdw...

Mesoporous slit-structured NiO materials were prepared through a simple hydrothermal route with sodium dodecyl benzene sulfonate (SDBS) as an additive. The as-prepared NiO samples presented high specific capacitance of over 1700 F g(-1) in the potential range from 0.10 to 0.56 V (vs. Hg/HgO/6 mol L(-1) KOH) at a constant current of 2 A g(-1), and good capacitance retention of ∼90% after 1000 co...

A facile hydrothermal route has been developed for the synthesis of nearly spherical copper nanoparticles, copper nanocubes and ribbon-like network nanostructures. The as-prepared copper nanostructures were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), and...

Efficiency of a sequential ultrafiltration – ion exchange purification system was studied by testing separation of an anionic surfactant (SDBS) from aqueous solutions. Commercially available ultrafiltration membranes with cut-off values of 5, 10, and 30 kDa were used for the tests. The ion exchange processes were carried out on five types of ion-exchange resins – both macroporous and gel-based....

Based on bubble electrospinning (BE), a modified free surface electrospinning (MFSE) using a cone-shaped air nozzle combined with a solution reservoir made of copper tubes was presented to increase the production of quality nanofibers. In the MFSE process, sodium dodecyl benzene sulfonates (SDBS) were added in the electrospun solution to generate bubbles on a liquid surface. The effects of appl...

Constitutive engineering by adding halide anions is one effective way to improve the performance of photodetectors adjusting bandgap. In this study, a mixed-anion perovskite thin film was facile fabricated post-processing pure FAPbI3 with formamidinium bromide (FABr) solution. addition, manufactured used as light absorption layer, SnO2-SDBS electron transport and spiro-OMeTAD hole injection lay...