Metrological problems in automatic production

Conclusions In order to ensure the successful development and application of automatic systems and, in the first place, high quality for their production, it is necessary to carry out a large amount of metrological work which has not been previously performed by the State Committee's system in working out theoretical foundations and methods of normalizing metrological characteristics of measuring instruments for automatic control, regulating and monitoring systems; in developing methods and equipment for testing and checking measuring devices of automatic system; and in carrying out state testing of automatic measuring systems.The State Committee and its agencies should in future provide metrological evaluations of control, regulation and monitoring systems as a whole.     

A magnetically driven piston pump for ultra-clean applications

A magnetically driven piston pump for xenon gas recirculation is presented. The pump is designed to satisfy extreme purity and containment requirements, as is appropriate for the recirculation of isotopically enriched xenon through the purification system and large liquid xenon time projection chamber of EXO-200. The pump, using sprung polymer gaskets, is capable of pumping more than 16 standard liters per minute of xenon gas with 750 Torr differential pressure.     

Synthesis of optimum slider-crank mechanismsCИ

For the spatial slider-crank mechanism formulas are obtained to allow the user determine the link sizes and slider offset for a predetermined stroke with an acceptable pressure angle at the extremes of slider travel as well as by a given angle between the crosshead guide of the slider and a plane in which the crank revolves. Formulas for determining the sizes of links of the plane slider-crank mechanism as a special case of the spatial mechanism are also presented. The particular cases of mechanisms havingequal angles of pressure as well as at extreme values of an angle between crosshead guide and the revolution plane of the crank are discussed. It is shown, that the plane mechanism case provides maximum slider travel when other things are equal.     

Direction of innovations of pipeline devices for polluted media

In this article, the methodological principle of separation of functions in designs of gas and oil pipeline devices (gate valves, cocks, valves, fittings, etc.) is formulated for conditions of operation in polluted working media and the trends of application of this principle in design and technology are discussed. It is shown that this principle is most fully and usefully put into practice in design of highly reliable IGR type of shutoff-control (multipurpose) valve protected by Russian Federation patent for invention. The critical nature of the problem of shutoff-control valve quality is proved by comparative analysis of the special features of modern designs of similar articles, which affect the important hydraulic characteristic of the flow section of the valves. In the proposed design of the IGR valve, the flaws revealed have been removed and its merits with respect to hydraulic resistance and flow characteristics, which fully correspond to the current requirements in the gas industry, have been shown theoretically.     

The Effect of a High-Voltage Diffuse Gas Discharge on Microbiological Cultures

The results are given of investigation of the inactivation of microbiological cultures in moist and dry states by low-temperature plasma of a low-power diffuse pulse-periodic discharge (up to 5 W) initiated in the air at a pressure of tens of torr and with an interelectrode gap of up to 10 cm. Escherichia coli and Staphylococcus epidermidis, inoculated onto test samples in an amount of ∼10⁸, were used as reference cultures. It is found that a complete sterility of moist and dry test samples is attained after 15 minutes of treatment at an average discharge power of 0.3–0.4 W and 3–4 W, respectively. The inference is drawn that charged particles play a determining part in the bactericidal effect of the discharge.__________Translated from Teplofizika Vysokikh Temperatur, Vol. 43, No. 3, 2005, pp. 367–373.Original Russian Text Copyright © 2005 by S. N. Buranov, S. V. Voevodin, I. A. Voevodina, P. S. Zubeev, V. I. Karelin, P. B. Repin, V. D. Selemir, and S. Yu. Usacheva.     

Enhancement of Pyro-Hydrometallurgical Technology of Dephosphorization of Brown Iron Ore of the Lisakovsk Field by Hot Leaching Method

Metallurgist - Brown iron ore constitutes about 13% of the global ore reserves and is widespread throughout the world. Brown iron ore is characterized by a significant content of harmful phosphorus...     

Reconstructing the particle direction in an extended aperture of the PAMELA apparatus using the coordinate-sensitive calorimeter

A method for reconstructing the track and the direction of a particle hitting the detector using a coordinate-sensitive calorimeter has been developed in the context of the PAMELA experiment. To extend the standard detector aperture determined by the geometrical dimensions of the magnetic spectrometer, a special trigger is used for particles that cross the position-sensitive calorimeter at large angles and interact beyond the sensitive region of the magnetic spectrometer. Owing to this method, it will be possible not only to measure the spatial anisotropy of cosmic rays, but also to discriminate between the electron and proton components and study their energy spectra.     

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.