On the Possibility of Observing Third Sound on 3He

This paper focuses on the hydrodynamics of third sound on a superfluid ³ He film. We solve the hydrodynamical equations in the limit of thick films with weak interaction with the substrate. The surface tension at the free interface is shown to have a large effect on the third sound velocity and on the attenuation for frequencies larger than 1Hz. In the case of a diffusely scattering substrate a ripplon-like dispersion relation is found for this frequency range.     

On calculation of the power indices with allowance for the agent preferences

In the general case, complexity of the algorithm to calculate the power indices grows exponentially with the number of voting agents. Yet the volume of calculations may be reduced dramatically if many coalitions have equal numbers of votes. The well-known algorithm for calculation of the Banzhaf and Shapley-Shubik indices was generalized, which enables fast calculation of the power indices where entry of the voting agent into a coalition depends on its preferences over the set of the rest of agents.     

Analysis of light-induced degradation mechanisms in α-Si:H/μc-Si:H solar photovoltaics

The photoinduced degradation of the i-α-Si:H layer in tandem photovoltaic converters based on α-Si:H/μc-Si:H structures is analyzed in terms of the “H-collision-” and “floating-bond” models and modifications of these. It is shown that the form of the degradation dependence is well described by all models under consideration. Compared with the modified models, the original “H-collision-” and “floating-bond” models yield estimates for saturated dangling-bond concentrations, which are always dependent on the intensity of the light that caused the degradation. The modified “floating-bond” model makes it possible to exclude this dependence, and the modified “H-collision” model describes the occurrence of this dependence in a certain range of illumination intensities and its absence in another range, which is in best agreement with experimental data.     

New Variational Solutions for the Rolling of Flanged Sections in Universal Roll Passes

Metallurgist - The variational principle of minimum total power and modern computational means are used to describe the deformation of metal in and to determine the power/force conditions for...     

Influence of the position of InGaAs quantum dot array on the spectral characteristics of AlGaAs/GaAs photovoltaic converters

Results of a comparative study of the internal quantum yield of AlGaAs/GaAs photovoltaic converters (PVCs) with variable position of the array of vertically coupled InGaAs quantum dots (QDs) are presented. It is established that the QD array placed immediately at the i-region/base interface does not change the PVC sensitivity compared to that for QDs arranged inside the i-region of the p-n junction. However, the QD array shifted to the base or the back potential barrier decreases the contribution of a base layer to the PVC photocurrent and reduces the photosensitivity of the QD-based medium.     

Magnetic Ordering in 3He Nano-Clusters

Simultaneous measurements of magnetic susceptibility from 0.5 to 10 mK and pressure from 2.88 to 3.54 MPa have been made in ³ He nano-clusters embedded in a ⁴ He matrix, following phase separation. The susceptibility of the 3.54 MPa, all-solid sample behaves similarly to that of bulk ³ He for v=21.3 cm ³ /mole, with a Weiss constant =–250K. For the 2.88 MPa, liquid-droplet sample, =140K, indicating a ferromagnetic tendency, similar to 2-D films at some coverages. At intermediate pressures, has a peak near 1.05 mK, but without a discontinuity. For all samples, had a solid-like contribution to the lowest temperatures. Magnetic ordering in nano-clusters appears to be different than the U2D2 phase of bulk ³ He.     

Experimental investigation of heat transfer during condensation of steam from a steam-water mixture on cold water jets at high pressure

Results from experimental investigations of heat transfer during the condensation of steam from a steam-water mixture on cold water jets at high pressure are presented. These data are essential for developing high-pressure direct-contact feedwater heaters, such as those for power units at nuclear power stations equipped with lead-cooled reactors.