A simple radionuclide-driven single-ion source

We describe a source capable of producing single barium ions through nuclear recoils in radioactive decay. The source is fabricated by electroplating (148)Gd onto a silicon α-particle detector and vapor depositing a layer of BaF(2) over it. (144)Sm recoils from the alpha decay of (148)Gd are used to dislodge Ba(+) ions from the BaF(2) layer and emit them in the surrounding environment. The simultaneous detection of an α particle in the substrate detector allows for tagging of the nuclear decay and of the Ba(+) emission. The source is simple, durable, and can be manipulated and used in different environments. We discuss the fabrication process, which can be easily adapted to emit most other chemical species, and the performance of the source.     

Assessment of the effectiveness of compaction of ShKh15 steel powders by hot extrusion

Conclusions Hot extrusion enables high-density steel to be obtained from an ShKh15 powder at a reduction = 2.15 (degree of deformation 33%). The strength of P/M ShKh15 steel after extrusion and annealing lies in the range 720–780 MPa, and thus surpasses the strength of the same steel produced by casting (650–700 MPa), while the ductility characteristics of the two steels are comparable.Translated from Poroshkoyaya Metallurgiya, No. 1(289), pp. 25–28, January, 1987.A 1.0% C-1. 5% Cr ball-bearing stell grade — Publisher.Deceased.     

Improving the Design Reliability of Petroleum Pipeline Components on Repair

Developments are considered that may appreciably improve the design reliability in the repair of petroleum pipeline components.     

Effect of Long-Term Heat Treatment on the Acceptor Behavior of Gold in Silicon

Data are presented on the electrical activity of Au in Czochralski Si heat-treated and diffusion-doped under various conditions. The results are interpreted in terms of force fields responsible for changes in the concentration of electrically active centers. Long-term heat treatment between 700 and 1050°C is shown to have a significant effect on the acceptor behavior of Au in diffusion-doped Si. The concentration of Au acceptors is sensitive to the surface condition in the course of heat treatment: a tungsten coating increases the Au concentration in the bulk of diffusion-doped Si.     

Output power limitation in a Xe laser pumped by a periodic-pulsed electric beam

We report the experimental and theoretical characteristics of generation at 1.73 μm for a Xe laser pumped with an electron beam of a pulsed electron accelerator operating at a repetition rate of up to 100 Hz. A decrease in the average output power with time is caused by electron-beam heating of the active medium.