Dependence of the surface morphology of ultrathin bismuth films on mica substrates on the film thickness

The results of studying the surface of 15- to 100-nm-thick bismuth films by atomic-force microscopy are reported. The near-linear character of the dependences of the average surface roughness and the average height of growth patterns on the film thickness is established. It is found that the average crystallite size increases, as the film thickness is increased. A slight dependence of the crystallite size on the film thickness is observed at thicknesses in the range of 27–70 nm.     

The role of information technology in rotor balancing

The potential of multimedia interactive simulators is discussed. As an example, the simulator for a system measuring vibration parameters is considered. By means of this simulator, the components and operating principle of the measuring system may be studied in dialog mode, as is demonstrated. The application of this system not only as a measuring instrument but also for the reduction of vibration in rotating mechanisms (rotor balancing) is demonstrated.     

Sulfhydryl phosphorus-containing collectors in flotation of copper–nickel platinum-group metals

The analysis involves influence of sulfhydryl phosphorus-containing collectors (SPC) on flotation of copper–nickel ore-bearing metals from platinum group. Efficiency of SPC and butyl xanthate combination is illustrated, and their optimal ratio is determined. The authors study influence of the test agents on electrode potential and hydrophobic behavior of pyrrhotine, pentlandite and platinum black. UV and IR spectrophotometry has shown origination of disulfide di-isobutyl dithiophosphinate on the surface of pyrrhotine.     

Choice of line reactors for HVDC lines and back-to-back links

Recommendations on the choice of a line reactor for HVDC lines and back-to-back links have been systematized. It is shown how the HVDC self-resonant frequencies should be detuned from resonance with network harmonics and how long-standing operation of BTBL and HVDC should be provided in commutations, failures, lightning high voltages, and short-circuit current.