Digital Measuring Microscope

A measuring microscope equipped with digital measuring transducers is considered. The transducers of linear and angular displacement and measuring heads for guidance and disconnection are constructed according to the same basic circuit design using the same fundamental base. This simplifies and cheapens the construction and facilitates maintenance of these instruments.__________Translated from Izmeritel’naya Tekhnika, No. 5, pp. 20–23, May, 2005.     

Friction machine for accelerated wear tests of frictional rolling elements

The construction of a friction machine for accelerated tests of friction rolling elements for frictional torque and wear. A study of the influence of rolling resistance force, rotational speed, and external load on the wear of samples has been carried out. A regression mathematical model that makes it possible to predict the amount of wear on the components of the friction pair under loading conditions has been obtained.     

Millimeter-Wave Transmittance Measurements on Ferrites Near Ferromagnetic Resonance

This paper presents complex dielectric permittivity and magnetic permeability measurements of pure and diluted barium ferrites in the millimeter-wave frequency range. A broadband quasi-optical millimeter-wave spectroscopy with backward-wave oscillators as high-power tunable sources of coherent radiation has been utilized. The real and imaginary parts of the dielectric permittivity and magnetic permeability as functions of frequency are computed from the transmittance spectra. A magneto-optical approach in millimeter waves has been successfully employed for the separation of the dielectric and magnetic effects and the simultaneous determination of the magnetic and dielectric parameters of barium ferrite materials near ferromagnetic resonance.     

Structure and composition of Cu<Subscript>2</Subscript>O films produced by anodizing copper foil on fiberglass laminate

The effect of process conditions on the composition and structure of anodic Cu₂O films grown in sulfate-chloride electrolytes has been studied using Auger electron spectroscopy, x-ray diffraction, and atomic force microscopy. The results demonstrate that the copper and oxygen depth profiles in the anodic copper(I) oxide films (ACOFs) are similar in shape. The copper content near the surface is only slightly lower than the bulk copper content. Starting at a depth of 9 nm, the Cu content is constant at an average of 62.7 at %. The Cu₂O films grown at a current density j = 3 mA/cm² have the most perfect stoichiometry, with deviations only in the surface layer. Anodic oxidation produces unoriented polycrystalline films of complex composition. In addition to Cu₂O, the films contain CuCl and trace levels of copper. Raising the anode current density influences, for the most part, the formation of (111)-oriented crystallites, changing their orientation from (111) to (220). We assume that nonmetal (oxygen or chlorine) atoms are incorporated into the cubic structure of copper without changing its symmetry but increasing its unit-cell parameter: from 0.3607 (Cu) to 0.426 (Cu₂O) and to 0.541 nm (CuCl).     

Operating features of a high-voltage spark gap switch with gas blow normal to the breakdown path in a repetitively pulsed mode

The results of studies of a high-voltage two-electrode spark gap switch (SGS) with forced gas blow at an operation voltage of up to 1.2 MV are presented. An SGS filled with nitrogen as the working gas at a pressure of up to 16 atm operated as the high-voltage switch of a high-current nanosecond electron accelerator. The gas flow was directed normally to the breakdown path. The SGS switched a 50-Ω forming line with an electrical length of 10 ns to a matched load. The voltage rise time across the electrodes before breakdown was ～25µs. A stable repetitively pulsed mode is realized at operating voltages of 100–680 kV and pulse repetition rates of up to 270 Hz with a standard deviation of the pulse breakdown voltage of ≤1%. The physical mechanisms that determine unstable operation of the device during self-breakdown are analyzed.     

Deep purification of detonation nanodiamond material

The paper presents new alternative procedures of chemical purification of detonation nanodiamonds and diamond-bearing detonation soot to remove water-insoluble metal-containing impurities through a high-temperature treatment using solutions of complexons of concentration 0.5 to 20 wt %, where the ratio between the detonation nanodiamond material and the complexon is above 0.2. The following substances can be used as complexons: sodium 2,3-dimercaptopropanesulfonate, disodium dihydrogen ethylenediaminetetraacetate (Trilon), thiocarbamide, potassium rhodanate, dicyandiamide, hexamethylenetetramine. Purification of detonation nanodiamonds can be also performed by exposing them to an ultrasonic action. A combination of the ultrasonic treatment and treatment with complexon solutions has proved most efficient, significantly reducing the amount of metal-containing impurities.     

A low-power multichannel integrated circuit for reading out the signals of silicon detectors

An integrated circuit for reading signals from silicon detectors intended for systems for measuring charges of cosmic particles and nuclei in space-based experiments is described. It contains a 16-channel charge-sensitive amplifier and two additional operational amplifiers produced by the 0.35 μm CMOS process. The power consumption of the charge-sensitive amplifier is ≤1 mW/channel, and the rms deviation of the noise does not exceed 2000 electrons. Circuit designs for separate stages of the integrated circuit and experimental characteristics are given.     

Bore wear caused by firing steel monoblock bullets

The peculiar character of bore wear by steel monoblock bullets is presented. An effect of the turbulence of propellant gas with erosion particles on the wear of the near-surface bore layers in the process of firing is discovered.     

The cutting energy and the rate of removal of the margin in abrasive superfinishing

A relation is established between the cutting energy in superfinishing, which is a generalized characteristic of abrasive machining, and the removal of the margin, which is one of the basic characteristics of this process. This approach permits effective improvement in abrasive machining.