Ultrasonic control of the level of the heterogeneous surface medium in mining

Topical One of the major problems of controlling the level of ore or moving fluid (slurry) is recording the reflected signal. Due to evident heterogeneity of the reflecting surface, dispersion of an ultrasonic wave greatly attenuates the reflected signal making it difficult to detect it against random noises. In this case, the only way to solve this problem is application of acoustic reflectors. To analyze this issue, a scheme of the conventional reflector with a radiator-receiver is under study. Efficiency of the acoustic reflector in recording the reflected signal is evaluated. The design of developed recording devices for ultrasonic control over fluid and solid media with heterogeneous surfaces allows increasing their accuracy and reliability due to receiving and transmitting a low-level signal in industrial noises. Industrial testing indicates that the developed ultrasonic device controlling lumpiness of ore materials produces a measuring error of under 1.5%, while efficiency of technological aggregates produced by the ultrasonic method based on measuring the level of the slurry in technological chutes of concentration plants can be evaluated with the ±1% error.

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How to Obtain a SAR Image of the Ocean Surface That Is Actually Free from The Impact of Orbital Velocities

Journal of Marine Science Research and Oceanography ◽

10.33140/jmsro.04.02.04 ◽

2021 ◽

Vol 4 (2) ◽

Keyword(s):

Synthetic Aperture Radar ◽

Ocean Surface ◽

Synthetic Aperture ◽

Small Scale ◽

Matched Filtering ◽

Sar Image ◽

Synthesis Procedure ◽

Reflected Signal ◽

Reflecting Surface ◽

The Impact

As is known, the main problem in interpreting images of the ocean surface formed by microwave synthetic aperture radar (SAR) is the distortions introduced by the orbital movements of the small-scale (centimeter and decimeter) ripples in the field of large waves. The point is that the standard aperture synthesis procedure is a matched filtering operation aimed at extracting from the reflected signal a part that has a phase that changes according to a known scenario corresponding to a stationary reflecting surface.

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Automated complex “Miсron” for determining measurement error of microwave radio interferometers

Izmeritel`naya Tekhnika ◽

10.32446/0368-1025it.2020-10-60-64 ◽

2020 ◽

pp. 60-64

Author(s):

D. Ye. Bezrukov ◽

N. S. Kornev ◽

N. A. Makarichev ◽

K. V. Mineev ◽

A. V. Nazarov ◽

...

Keyword(s):

Theoretical Estimate ◽

Displacement Transducer ◽

Linear Displacement ◽

Measuring Error ◽

Accuracy Class ◽

Surface Movement ◽

Microwave Radio ◽

Reflecting Surface ◽

Linear Displacement Transducer

The technique of radiointeroferometric measurements is presented and a theoretical estimate of the measuring error the reflecting surface movement is given. The movement are measured with microwave radio interferometers. The automated complex “Miсron” design and principle of operation are described. The complex is intended for experimental determination of the error in measuring the movement of a reflecting surface, as well as for primary and periodic verification of microwave radio interferometers. The complex “Miсron” includes a measuring instrument of the 3rd accuracy class – an incremental linear displacement transducer LIR-7A, which measures the reflecting surface movement of the test object. For the “Miсron” complex verification of the longitudinal movement measuring line is provided, which makes it possible to verify the LIR-7A transducer without dismantling it. Planeparallel gauge blocks or similar standards can be used as the initial standard for verification. The comparison of the movement measured values determined during verification and obtained by an alternative method providing the required accuracy of radio interferometric measurements is carried out.

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Ultrasonic Control of the Formation of Gypsum Binders

Materials Science Forum ◽

10.4028/www.scientific.net/msf.968.122 ◽

2019 ◽

Vol 968 ◽

pp. 122-127 ◽

Cited By ~ 1

Author(s):

Vladimir Kersh ◽

Andrey Kolesnikov ◽

Nikolay Xlytsov ◽

Aljona Foshch

Keyword(s):

Ultrasonic Method ◽

Setting Time ◽

Ultrasound Velocity ◽

Steady State Condition ◽

Ultrasonic Control ◽

Ultrasonic Signals ◽

Setting Times ◽

Plastic Strength ◽

Initial Setting ◽

Insulating Properties

This paper presents the research method of hardening process of gypsum binders and composites, based on them, using the ultrasonic method. Modern construction composites, based on higher water resistance gupsym, contain the coarse aggregate particles, giving them heat and sound insulating properties. One of the frequent purposes, designing such composites, is the slowdown of the processes of setting, so it allows the builders to work with the material for a sufficiently long period. The use of standard control penetration methods of the setting processes for the considered composites becomes difficult because of the presence of course particles in the binder paste. The ultrasonic method is proposed to use alternatively to study the process of setting. For its implementation, the technique has been developed, based on the use of ultrasound systems for quality control of concrete products. The transit time of ultrasonic signals through the layer of hardening binder paste with the fixed thickness was measured in a regular intervals until completely setting. On the basis of the obtained data, the ultrasound velocity was calculated and the setting time was determined. For this purpose, a differential curve of the time of ultrasound transmission was plotted, and the period was considered, at which the transition to the steady-state condition was carried out, it is equivalent to the end of the setting. The initial setting was determined by the first trip of the measuring equipment, corresponding moment of the formation of the primary crystal structure of the composite, which has sound-transmission properties. To verify the values of the setting time, the simultaneous measurement of the plastic strength of the model system was used. The moments of the beginning and the end of the setting, as well as the ultrasound velocities which were typical for these moments, were determined with the plastic strength. The obtained velocity values allowed to find the setting times of other composites. The actual setting time is estimated based on the values, obtained by all the available methods. The model, based on percolation theory, has been proposed for analyzing the physicochemical phenomena during the setting.

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Ultrastructure and Morphology of the Neurospora Crassa Cell Wall Mutants, Slime And Slime X, Using Tem and Sem

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100090257 ◽

1976 ◽

Vol 34 ◽

pp. 54-55

Author(s):

Karen S. Howard ◽

H. D. Braymer ◽

M. D. Socolofsky ◽

S. A. Milligan

Keyword(s):

Cell Wall ◽

Neurospora Crassa ◽

Wild Type ◽

Morphological Comparison ◽

Small Areas ◽

Solid Media ◽

Thin Sectioning ◽

X Cells ◽

Mutant Cells ◽

Isolated Cell

The recently isolated cell wall mutant slime X of Neurospora crassa was prepared for ultrastructural and morphological comparison with the cell wall mutant slime. The purpose of this article is to discuss the methods of preparation for TEM and SEM observations, as well as to make a preliminary comparison of the two mutants.TEM: Cells of the slime mutant were prepared for thin sectioning by the method of Bigger, et al. Slime X cells were prepared in the same manner with the following two exceptions: the cells were embedded in 3% agar prior to fixation and the buffered solutions contained 5% sucrose throughout the procedure.SEM: Two methods were used to prepare mutant and wild type Neurospora for the SEM. First, single colonies of mutant cells and small areas of wild type hyphae were cut from solid media and fixed with OSO4 vapors similar to the procedure used by Harris, et al. with one alteration. The cell-containing agar blocks were dehydrated by immersion in 2,2-dimethoxypropane (DMP).

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TEM processing procedure for a bacillus organism grown on solid media

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100160674 ◽

1990 ◽

Vol 48 (3) ◽

pp. 624-625

Author(s):

Jane Payne ◽

Philip Coudron

Keyword(s):

Electron Microscopy ◽

Room Temperature ◽

Fume Hood ◽

Vacuum Aspiration ◽

Solid Media ◽

Transmission Electron ◽

Solid Agar ◽

Processing Procedure ◽

Agar Media ◽

Rat Bone

This transmission electron microscopy (TEM) procedure was designed to examine a gram positive spore-forming bacillus in colony on various solid agar media with minimal artifact. Cellular morphology and organization of colonies embedded in Poly/Bed 812 resin (P/B) were studied. It is a modification of procedures used for undecalcified rat bone and Stomatococcus mucilaginosus.Cultures were fixed and processed at room temperature (RT) under a fume hood. Solutions were added with a Pasteur pipet and removed by gentle vacuum aspiration. Other equipment used is shown in Figure 3. Cultures were fixed for 17-18 h in 10-20 ml of RT 2% phosphate buffered glutaraldehyde (422 mosm/KgH2O) within 5 m after removal from the incubator. After 3 (30 m) changes in 0.15 M phosphate buffer (PB = 209-213 mosm/KgH2O, pH 7.39-7.41), colony cut-outs (CCO) were made with a scalpel.

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