Shaping the Toroidal Section of End Mills

The shaping of the toroidal cutting section of end mills is considered. Methods are devised for selecting the positional parameters in shaping the helical rake surface on the toroidal section. Relations are established between the geometric parameters of the end mill in the toroidal section.     

Automated recordkeeping of nuclear materials at electric power plants powered with a water-moderated-water-cooled nuclear reactor

Conclusions The automated nuclear-material recordkeeping system based on the NUMIS-2 program is at present being introduced at the Novororonezh electric power plant. Concurrently, the program is being modified in order to allow its use by the computer model being created in the COMECON member-nations. In the long term, it is expected that the recordkeeping program will become a component part of a single automated control systems of individual electric power plants.The NUMIS-2 program was approved for nuclear-material recordkeeping use after it was tested on the first fuel load of the fourth unit of the Novovoronezh electric power plant. The experiment confirmed the feasibility of automating the processing and storing of nuclear-material information and of recording that information and on the standard computer carriers of information. In principle, these same records can be submitted to the national recordkeeping service (or to the International Atomic Energy Agency) for their further immediate processing by means of the computer program employed by the service. In this manner, the recordkeeping system becomes closed, which makes it promising.We note that the propesed nuclear-material recordkeeping system satisfied the basic requirements of recordkeeping by computer laid down by the International Atomic Energy Agency as well as the required order of reporting by the plants under the control of the Agency.Translated from Atomnaya Énergiya, Vol. 45, No. 4, pp. 267–270, October, 1978.     

Photoluminescence and Electrical Conductivity of As<Subscript>2</Subscript>S<Subscript>3</Subscript>〈Au〉 and As<Subscript>2</Subscript>S<Subscript>5</Subscript>〈Au〉 Glasses

The 77-K photoluminescence spectra of (As₂S₃)_{100 − x} Au_x and (As₂S₅)_{100 −x} Au_x (0 ≤ x ≤ 0.04) semiconducting glasses are measured for the first time. At low doping levels, the spectra of the (As₂S₅)_{100 − x} Au_x glasses are split into two components, one of which arises from the Au dopant. The temperature-dependent conductivity of the glasses shows two breaks at low Au concentrations and anomalous behavior in the range 300–360 K. Qualitative analysis of the conductivity data suggests that most of the impurity atoms have saturated valence bonds and form solid solutions with host atoms, changing the band gap of the material. A small fraction of the impurity atoms, those having unsaturated valence bonds, produce an electrically active level responsible for impurity conduction.__________Translated from Neorganicheskie Materialy, Vol. 41, No. 7, 2005, pp. 876–880.Original Russian Text Copyright © 2005 by Babaev, Kamilov, Sultanov, Askhabov, Terukov.     

Managing Clouds, Smart Networks and Services: A Report on APNOMS 2011

This article presents a report on APNOMS 2011, which was held September 21–23, 2011 in Taipei, Taiwan. The theme of APNOMS 2011 was “Managing Clouds, Smart Networks and Services.”     

Polymer Composites Based on Shungite and Taunite-M Carbon Nanomaterial for Radioprotective Coatings

Protection of Metals and Physical Chemistry of Surfaces - The present brief review presents the results of studies of the electrical conductivity and microwave properties of polymer composites...     

High cyclic fatigue performance of Al–Cu–Mg–Ag alloy under T6 and T840 conditions

High cyclic fatigue (HCF) behavior of an AA2139 alloy belonging to Al–Cu–Mg–Ag system in T6 and T840 conditions was examined. The T840 treatment involving cold rolling with a 40% reduction prior to peak ageing provides an increase in tensile strength compared with the T6 condition. However, fatigue lifetime for two material conditions was nearly the same since there is weak effect of thermomechanical processing on micro-mechanisms of crack initiation and growth.     

Resonant coherent excitation of hydrogen-like ions planar channeled in a crystal; Transition into the first excited state

The presented program is designed to simulate the characteristics of resonant coherent excitation of hydrogen-like ions planar-channeled in a crystal. The program realizes the numerical algorithm to solve the Schrödinger equation for the ion-bound electron at a special resonance excitation condition. The calculated wave function of the bound electron defines probabilities for the ion to be in the either ground or first excited state, or to be ionized. Finally, in the outgoing beam the fractions of ions in the ground state, in the first excited state, and ionized by collisions with target electrons, are defined. The program code is written on C++ and is designed for multiprocessing systems (clusters). The output data are presented in the table.Program summaryProgram title: RCE_H-like_1Catalogue identifier: AEKX_v1_0Program summary URL: http://cpc.cs.qub.ac.uk/summaries/AEKX_v1_0.htmlProgram obtainable from: CPC Program Library, Queen?s University, Belfast, N. IrelandLicensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.htmlNo. of lines in distributed program, including test data, etc.: 2813No. of bytes in distributed program, including test data, etc.: 34 667Distribution format: tar.gzProgramming language: C++ (g++, icc compilers)Computer: Multiprocessor systems (clusters)Operating system: Any OS based on LINUX; program was tested under Novell SLES 10Has the code been vectorized or parallelized?: Yes. Contains MPI directivesRAM: <1 MB per processorClassification: 2.1, 2.6, 7.10External routines: MPI library for GNU C++, Intel C++ compilersNature of problem: When relativistic hydrogen-like ion moves in the crystal in the planar channeling regime, in the ion rest frame the time-periodic electric field acts on the bound electron. If the frequency of this field matches the transition frequency between electronic energy levels, the resonant coherent excitation can take place. Therefore, ions in the different states may be observed in the outgoing beam behind the crystal. To get the probabilities for the ion to be in the ground state or in the first excited state, or to be ionized, the Schrödinger equation is solved for the electron of ion. The numerical solving of the Schrödinger equation is carried out taking into account the fine structure of electronic energy levels, the Stark effect due to the influence of the crystal electric field on electronic energy levels and the ionization of ion due to the collisions with crystal electrons.Solution method: The wave function of the electron of ion is the superposition of the wave functions of stationary states with time-dependent coefficients. These stationary wave functions and corresponding energies are defined from the stationary Schrödinger equation. The equation is reduced to the problem of the eigen values and vectors of Hermitian matrix. The corresponding matrix equation is considered as the linear equation system. Then the time-dependent coefficients of the electron wave function are defined from the Schrödinger equation, with a time-periodic crystal field. The time-periodic field is responsible for the transitions between the stationary states. The final time-dependent Schrödinger equation represents the matrix equation which has been solved by means of the QR-algorithm.Restrictions: As expected the program gives the correct results for relativistic hydrogen-like ions with the kinetic energies up to 1 GeV/u and at the crystal thicknesses of 1–100 μm. The restrictions are: first, the program might give inadequate results, when the ion kinetic energy is too large (>10 GeV/u); second, the unaccounted physical factors may be significant at specific conditions. For example, the spontaneous emission by exited highly charged ions, as well as both energy and angular spread of the incident beam, could lead to additional broadening of the resonance. The medium polarization by the electric field of ion can influence the electronic energy levels of the ion in the non-relativistic case. The role of these factors was discussed in the references. Also, the large crystal thickness may require large computational time.Running time: In general, the running time depends on the number of processors. In our tests we used the crystal thickness up to 100 μm and the number of 2.66 GHz processors was up to 100. The running time was about 1 hour in these conditions.     

Reflective light modulator based on epsilon-GaSe crystal

We report the results of investigating a low-voltage, polarization-insensitive, reflective-type modulator based on an epsilon-GaSe crystal and operated at the 1.960-eV line of a He-Ne laser. We demonstrate that the modulation in an Al-epsilon-GaSe-Cu device results mainly from the Franz-Keldysh effect. Relatively high speed and low operating voltage could make these modulators with Schottky-barrier contacts attractive devices in the red range of the spectrum.