Equipment for Damping Hydraulic Shocks in Pressure Hydrotransport Facilities

Works of Georgian Technical University ◽

10.36073/1512-0996-2021-3-130-136 ◽

2021 ◽

pp. 130-136

Author(s):

Leon Makharadze ◽

Keyword(s):

Viscous Fluid ◽

Solid Material ◽

Back Pressure ◽

Hydraulic Fluid ◽

Main Pipeline ◽

Rupture Disc ◽

Flexible Diaphragm ◽

Hydraulic Shocks ◽

Separating Element

Newly developed equipment for damping hydraulic shocks in pressure hydrotransport facilities is reviewed in this article. This equipment includes a discharge, safety diaphragm, as well as a flexible diaphragm, which is connected to the main pipeline at both different ends of the backpressure valve. A rupture disc is attached to it from below and load is attached from above by means of a rod, so that it can efficiently act during movement of hydraulic fluid in the central main pipeline, i.e. when the flow to be transported contains abrasive contaminant of solid material. The load represents a piston, which is rigidly connected to the flexible diaphragm and the rupture disc and creates an airproof space filled with viscous fluid. At the same time, the lower space is isolated from the main pipeline by a flexible separating element before the backpressure valve and the upper space is also isolated by a flexible separating element located after the back pressure valve.

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Effects of Ion Beam Milling on Surface Topography

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100070862 ◽

1973 ◽

Vol 31 ◽

pp. 84-85

Author(s):

P.G. Pawar ◽

P. Duhamel ◽

G.W. Monk

Keyword(s):

Surface Topography ◽

Ion Beam ◽

Solid Material ◽

Beam Current ◽

Atomic Mass ◽

Micro Milling ◽

Ion Milling ◽

Controlled Atmospheres ◽

Milling Operations ◽

Sufficient Energy

A beam of ions of mass greater than a few atomic mass units and with sufficient energy can remove atoms from the surface of a solid material at a useful rate. A system used to achieve this purpose under controlled atmospheres is called an ion miliing machine. An ion milling apparatus presently available as IMMI-III with a IMMIAC was used in this investigation. Unless otherwise stated, all the micro milling operations were done with Ar+ at 6kv using a beam current of 100 μA for each of the two guns, with a specimen tilt of 15° from the horizontal plane.It is fairly well established that ion bombardment of the surface of homogeneous materials can produce surface topography which resembles geological erosional features.

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Contrast and Resolution in Alfresco Microscopy and Thick Specimens

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100096102 ◽

1972 ◽

Vol 30 ◽

pp. 570-571

Author(s):

J. R. Sellar ◽

J. M. Cowley

Keyword(s):

Solid Material ◽

Cell Design ◽

Current Interest ◽

High Voltage Electron Microscopy ◽

Voltage Electron ◽

Transmission Electron ◽

Environmental Cell ◽

Scanning Transmission ◽

Conventional Transmission Electron Microscope ◽

Transmission Microscope

Current interest in high voltage electron microscopy, especially in the scanning mode, has prompted the development of a method for determining the contrast and resolution of images of specimens in controlled-atmosphere stages or open to the air, hydrated biological specimens being a good example. Such a method would be of use in the prediction of microscope performance and in the subsequent optimization of environmental cell design for given circumstances of accelerating voltage, cell gas pressure and constitution, and desired resolution.Fig. 1 depicts the alfresco cell of a focussed scanning transmission microscope with a layer of gas L (and possibly a thin window W) between the objective O and specimen T. Using the principle of reciprocity, it may be considered optically equivalent to a conventional transmission electron microscope, if the beams were reversed. The layer of gas or solid material after the specimen in the STEM or before the specimen in TEM has no great effect on resolution or contrast and so is ignored here.

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