scholarly journals An investigation into the development of a portable, ultrasonic, density measuring instrument

1987 ◽  
Author(s):  
◽  
Nigel Douglas Hulse
Keyword(s):  
Physical Properties ◽  
Ultrasonic Transducer ◽  
Characteristic Impedance ◽  
Surrounding Medium ◽  
Density Measurement ◽  
Mining Industry ◽  
Organic Liquids ◽  
Probe Design ◽  
Measuring Instrument ◽  
Mineral Slurry

In the gold mining industry, one of the significant physical properties of the mineral slurry is its density and it is important to be able to measure this parameter in most processes. There are many techniques for determining the density of fluids, but because of the hostile, abrasive nature of mineral slurry, very few of these are suitable, This dissertation describes the deveiopment, construction and testing of a portable, ultrasonic, density measuring instrument. The instrument uses an ultrasonic transducer as the primary measuring element, and system operation is based on the fact that the driving impedance of the transducer varies with changes in the physical properties, and hence the characteristic impedance, of the surrounding medium into which the ultrasonic energy is being transferred. The technique may a-Lao be used to measure the relative concentrations of two liquids in a mixture or emulsion, provided that the characteristic impedances of the liquids are sufficiently dissimilar. The electronic circuitry is fairly straightforward, consisting essentially of an oscillator, driving circuit for the transducer and a voltage monitor to provide a d.c. voltage proportional to the impedance of the transducer, and hence to the density of the surrounding medium. Most of the research has been concentrated on the probe design, as the type of transducer, the type and thickness of facing material and the method of construction all contribute to the sensitivity of the instrument. A design of probe assembly has been developed that may be used for both slurry density measurement and the measurement of the ratio of aqueous to organic liquids in emulsion.

Coatings from Liquid and Supercritical Carbon Dioxide

2004 ◽  
Author(s):  
Yury Chernyak ◽  
Florence Henon
Keyword(s):  
Carbon Dioxide ◽  
Supercritical Carbon Dioxide ◽  
Physical Properties ◽  
Organic Liquid ◽  
Spray Coating ◽  
Organic Liquids ◽  
Liquid Density ◽  
Operating Pressure ◽  
Interfacial Tensions ◽  
Supercritical Carbon

This chapter describes several aspects of the use of carbon dioxide as a solvent or cosolvent in coating applications. The primary impetus for using carbon dioxide for this purpose has been the alleviation of volatile emissions and liquid solvent wastes. However, the special physical properties of liquid and supercritical carbon dioxide may offer some processing advantages over conventional organic or aqueous solvents. Liquid carbon dioxide is quite compressible, and a reduction in temperature results not only in a reduction in the operating pressure, but also in a significant increase in the liquid density to values of approximately 0.9 g/cm3. At these high liquid densities, carbon dioxide exhibits improved solvent performance, but with much lower viscosities and interfacial tensions than aqueous or organic liquid solvents. Under supercritical conditions, carbon dioxide also exhibits high densities, low viscosities, and improved solvent power. Low viscosities and interfacial tensions tend to facilitate the transport of the solvents into any crevices or imperfections on the surface to be covered, and this might prove advantageous in the coating of patterned or etched surfaces. Since carbon dioxide dissolves and diffuses easily into many different polymers and organic liquids, it can also be used to reduce the viscosity of coating solutions. Whether in the liquid or the supercritical state, the temperature and pressure of the mixture can be used to control its physical properties in ways that are impossible to achieve with traditional solvents. These distinguishing features have raised the level of industrial interest in carbon dioxide as a solvent for coating applications, beyond those based solely on environmental concerns. In this chapter, we will discuss current applications and research on the use of CO2 as a solvent for coatings. The first section deals with spray coating from supercritical CO2. Subsequent sections deal with the use of liquid coatings, such as spin and free meniscus coatings, and impregnation coatings. Since the start of the 20th century (ca. 1907), atomization has been the basis for conventional spray coating applications (Muirhead, 1974). Typically, atomization is caused by high shear of the coating fluid in air, leading to droplet or particle formation.

Impact of coseismic off-fault damage on the overall energy budget.

2020 ◽  
Author(s):  
Marion Y. Thomas ◽  
Harsha S. Bhat
Keyword(s):  
Physical Properties ◽  
Energy Budget ◽  
Complex Structure ◽  
Surrounding Medium ◽  
Fault Zones ◽  
Dissipated Energy ◽  
Inelastic Behavior ◽  
Radiated Energy ◽  
Mechanics Of Faulting ◽  
The Impact

<p>In the brittle part of the crust, deformation is usually perceived to be the result of displacement along fault planes, whose behaviors are controlled by their frictional properties. However, fault zones not only consist of a narrow fault core where slip occurs, they are also surrounded by a complex structure which is of key importance in the mechanics of faulting, hence in determining the overall energy budget. Indeed, as pointed out by the numerous field, geophysical, mechanical and laboratory observations, if the behavior of fault zones is intrinsically linked to the properties of the main sliding plane, it also depends on those of the surrounding medium.<strong>  </strong>In parallel, fault displacements may induce a substantial change in the physical properties of the surrounding medium. As a consequence, to improve our understanding of active fault zones, fault slip and the evolving physical properties must be studied as a unique system of stress accommodation and no longer as two distinct entities. To tackle this problem, we have developed a micromechanics-based constitutive model, thermodynamically argued, that can determine the inelastic behavior at macroscopic scale that arises from structural rearrangements at microscale. It is therefore the compulsory tool to emulate the strong coupling between the bulk and the fault that prevails during earthquakes. With this code, we can reproduce the strain rate sensitive, non-linear stress-strain relationship that leads to off-fault damage as a seismic event is propagating. We explore different scenarii and we show that there is a unique off-fault damage pattern associated with supershear transition of an earthquake rupture, that is also observed in the field.  We define, in return, the impact of damage on the propagation of the earthquake in itself and the generated waves. We conclude by assessing the kinetic energy, the dissipated energy and the radiated energy to define how energy is consumed within crustal systems during seismic events.</p>

Some physical properties of mixtures of certain organic liquids

1933 ◽  
Vol 29 (140) ◽  
pp. 1310 ◽  
Author(s):  
Violet Corona Gwynne Trew ◽  
Gertrude Margaret Clare Watkins
Keyword(s):  
Physical Properties ◽  
Organic Liquids

Separation at the Interface of a Circular Inclusion and the Surrounding Medium Under an Incident Compressive Wave

1970 ◽  
Vol 37 (2) ◽  
pp. 298-304 ◽  
Author(s):  
J. D. Achenbach ◽  
J. H. Hemann ◽  
F. Ziegler
Keyword(s):  
Focal Point ◽  
Characteristic Impedance ◽  
Surrounding Medium ◽  
Circular Inclusion ◽  
Front Face ◽  
Analytical Treatment ◽  
Compressive Wave ◽  
Tensile Wave ◽  
Shadow Side ◽  
Dynamic Loading Conditions

Separation at the interface of a circular inclusion embedded in a matrix of lower characteristic impedance and subjected to incident compressive waves is investigated, both experimentally and analytically. In the experiment, the compressive waves were generated by small explosive charges. For small charges, separation was not observed. As the explosive charge was increased, separation was observed at the “shadow side” of the inclusion. For still higher charges, separation was observed at the front face as well as at the shadow side of the inclusion. The qualitative analytical treatment is based on the methods of propagating stress discontinuities. It is shown that a compressive stress wave is converted into a tensile wave after a refraction and a reflection inside the inclusion. The reflected discontinuity of the tensile stress at the wave front is magnified upon passage through a focal point before reaching the shadow side of the inclusion. A divergence factor in conjunction with the closer proximity of the caustic to the back face reduces the level of tensile stresses reaching the front face. Separation is thus less likely to occur at the front face, which was verified experimentally. The results of this paper apply to the behavior of fiber-reinforced composites under dynamic loading conditions.

scholarly journals Design and Development of a Novel Ultrasonic Field Wetting Angle Measuring Instrument for Researching the Wetting of the Liquid–Solid Interface

Crystals ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1400
Author(s):  
Jingtao Zhao ◽  
Liping Ning ◽  
Zongming Jiang ◽  
Yinglong Li
Keyword(s):  
Composite Materials ◽  
Modal Analysis ◽  
Longitudinal Vibration ◽  
Ultrasonic Transducer ◽  
Technical Problem ◽  
Ultrasonic Field ◽  
Wetting Angle ◽  
Measuring Instrument ◽  
Solid Interface ◽  
Angle Measuring

A key technical problem in the preparation of Al-Ti-C grain refiner and other composite materials is the poor wetting of the Al-C interface, which greatly restricts the development of the preparation technology of related composite materials. In view of this scientific challenge, a novel ultrasonic field wetting angle measuring instrument has been designed to research the wetting behavior of the liquid–solid interface and ensure that preparation conditions are optimized. The dimensional parameters of the ultrasonic transducer and the horn in the novel ultrasonic wetting angle measuring instrument have been designed by theoretical calculation, and the modal analysis was performed for the ultrasonic horn using the functions of displacement and time. Modal analysis was utilized to optimize the dimension of the ultrasonic horn, and the natural frequency of the longitudinal vibration of the horn was reduced from 22,130 Hz to 22,013 Hz, resulting in an error rate between the actual value (22,013 Hz) and the design value (20 kHz) of less than 1%. In addition, the influence of different transition arc radiuses on the maximum stress of the optimized ultrasonic horn was analyzed.

scholarly journals Feasibility Investigations of the Possibility of Measurements, of the Ultrasonic Transducer Power Output at Ultrasonic-Therapy-Devices, with Piezoceramic Sensors

2011 ◽  
Vol 62 (5) ◽  
pp. 313-316
Author(s):  
Thomas Lekscha ◽  
Daniela Ďuračková
Keyword(s):  
Performance Measurement ◽  
Power Output ◽  
Ultrasonic Transducer ◽  
Measuring Method ◽  
Ultrasonic Power ◽  
Measuring Instrument ◽  
Ultrasonic Therapy

Feasibility Investigations of the Possibility of Measurements, of the Ultrasonic Transducer Power Output at Ultrasonic-Therapy-Devices, with Piezoceramic SensorsThe paper shows the essential results for the investigation of a new ultrasonic power measuring method, in articular for measuring the sonic pressure of ultrasonic therapy devices, by using piezoceramic sensors. The aim of this work is to develop a new measuring instrument for the fast performance measurement at ultrasonic-therapy-devices.

scholarly journals An appraisal of the properties of bottom waste obtained from bio-mass congestion to estimate the ways of its environmental use

2017 ◽  
Vol 19 (2) ◽  
pp. 33-37 ◽  
Author(s):  
Małgorzata Śliwka ◽  
Alicja Uliasz-Bocheńczyk ◽  
Małgorzata Pawul
Keyword(s):  
Physical Properties ◽  
Fluidized Bed ◽  
Coal Combustion ◽  
Mining Industry ◽  
Building Industry ◽  
Incineration Plant ◽  
Pot Experiments ◽  
Burning Parameters ◽  
Initial Research

Abstract The bottom waste obtained from bio-mass burning shows a huge variability of chemical and physical properties, depending on the kind of bio-mass, the type of a cauldron and burning parameters. The huge variability of the bottom ashes from the incineration plant and co-combustion of bio-mass makes it difficult to find any way to its management. In reality, only the bottom ashes from coal combustion and the small amount from lignite combustion are used, mainly in the building industry and in mining industry. The article presents the initial research, concerning the estimation of the properties of the bottom ashes obtained from bio-mass congestion in the fluidized-bed boiler to use them safely for the environment. To determine the influence of the tested waste on plants, a number of pot experiments have been conducted. The plants which have been used are recommended for phytotoxicity estimation, and are also used for biological reclamation.

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