We report on the observation of photoemission from the Cs∕GaN(0001) n-type interface by excitation of visible light in the transparency region of GaN. Under Cs adsorption, sharp decrease in photoemission threshold up to 1.3eV at 0.5 monolayer of Cs is found and shown to be due to formation of a charge accumulation layer in the near-interface region. An interesting phenomenon is revealed, namely, the appearance of an oscillation structure in spectra of photoyield. A model conception taking into account both the formation of charge accumulation layer and occurrence of multiple-beam interference in parallel-sided GaN epilayer is suggested.

The results of the numerical analysis of the flow capacity and other parameters at the different turbine vanes are presented in this paper. Two plane cascades with the same geometrical throat but with a different shape of suction surface have been investigated by means of the 2D Navier-Stokes code [1]. Stacked with these profiles two vane rows with tip meridional opening have been investigated by means of the 3D Euler code [2] and the 3D Navier-Stokes code [3]. The numerical investigation of two full-scale annular vane rows is confirmed by experimental mass flow performance, obtained in a range of exit isentropic Mach number on the mean diameter from Ma2 is = 0.7 to Ma2 is = 1.3.

The GTX100 is the most recent industrial gas turbine in the ABB fleet. The development of the GTX100 turbine blading was a joint project involving four companies. A thorough evaluation of various design requirements resulted in the selection of a single shaft three-stage turbine configuration. The cooling techniques employed for the blading are based on the knowledge from the Russian school of design for gas turbines. These techniques have been verified by a considerable amount of experimental data and field experience over a number of years. To incorporate western manufacturing methods, western suppliers were introduced at an early stage in the development. Most of the engineering development of the turbine blading was carried out in Russia. In order to achieve efficient cooperation between Russia and Sweden, specialists from both companies were stationed at alternating companies. The verification of the turbine design is divided into two steps. The first step is cold and hot component testing and the second is the overall engine testing.

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