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We present the first russian robot-telescope designed to make prompt observations of gamma-ray bursts (http://observ.pereplet.ru). The telescopes are near Moscow. The system of telescopes with prompt pointing rates connects to the internet. The main parameters are the following: Richter-Slefogt system telescope (355 mm, f/d=2.4); Richter-Slefogt system telescope (200mm, f/d=2.4); Flugge system telescope (280mm, f/d=2.5); TV-camera with 20x40 degree objective; Two CCD cameras (Pictor 416); One CCD Apogee Camera AP16E. The type of mount is German with 8 grad/sec slew rate. MASTER images stars down to 19 magnitude in a 1 min exposure covering 6 square degrees.Comment: 3 pages, 2 figure

Ni/NiO powdered nanoparticles with average sizes 10-30 nm were prepared by a levitation-jet method involving the condensation of Ni metal vapour in a mixture of helium with various amounts of air or oxygen. The process was undertaken with the application of a DC electric field up to 6.5 kV cm À1 . The particles were characterized by X-Ray diffraction, transmission electron microscopy, BET adsorption and vibrating sample magnetometry. It was found that the intensity of the applied electric field and partial oxygen pressure correlated with the main structural and magnetic parameters of the nanoparticles, such as average particle size, residual ratio of nickel, coercivity and maximum magnetisation. The specific surface area of the particles correlated with the magnitude of the external electric field. Room-temperature hysteresis loops of weakly oxidized nanoparticles show ferromagnetic-like behaviour, whereas the strongly oxidized ones exhibit a low-field ferromagnetic feature superimposed to a paramagnetic signal, regardless of the particle size. Magnetic measurements allowed for the estimation of the residual metal Ni content in the powdered nanoparticles, which can be as low as 0.04 at.% depending on oxygen partial pressure and external electric field strength.

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