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Showing 1 to 20 of 67 for “"Porous material"”.
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Porous material and process development for electrospray propulsion applications
… velocities. One such method involves the use of porous substrates to passively transport propellant towards conically shaped features of the same porous material. Historically, the methods of fabricating such small features (~150[mu]m tapered to ~20[mu]m over a height of ~150[mu]m) are …
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Oil Dries: A New Absorbent Material For Collection Of Ignitable Liquids From Semi-Porous Material
… of an ignitable liquid sample from a semi-porous surface such as concrete is especially difficult. For this purpose, two different solid oil dry absorbent materials, Instazorb and MAXXAbsorb, were researched for use of collection of ignitable liquid samples at a fire scene. These oil dries …
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Effect of flaw shape and penetrating fluids on hydraulic fracture initiation and propagation in porous material (gypsum)
The need of new energy sources to supply the energy consumption requirements of modern societies, in conjunction with the decrease in the conventional natural reserves of oil and gas and the improvement of the technological capabilities, led to a considerable growth in the exploitation of …
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Evaluation of the effects caused by a variation of parameters in a new process for the production of microporous polyethylene
… a proprietary process for the production of microporous polyethylene were investigated. The process involved the treating of a polyethylene film with two proprietary solutions at specific temperatures and in some cases required stretching of the material in the solutions. Specialized equipment was …
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Measurement of gas flow through porous structures using thz spectroscopy
… to measure the diffusion of liquid through materials. In this study, the ability of THz spectroscopy to measure the flow of gas in a porous material, packaging foam, is investigated. Specifically, Terahertz spectroscopy from 0.5 to 0.7 THz is used to measure the THz absorption of 1, 1 …
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Mechanics and Durability of Fiber Reinforced Porous Ceramic Composites
Porous ceramics and porous ceramic composites are emerging functional materials that have found numerous industrial applications, especially in energy conversion processes. They are characterized by random microstructure and high porosity. Examples are ceramic candle filters used in coal-fired …
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An experimental and analytical investigation of liquid moisture distribution in roof insulating systems
… to detect moisture concentrations in a highly porous glass fiber insulation. A new technique employing thermistor probes was used to measure thermal conductivity over a range of low moisture contents. The results indicate that the material's thermal conductivity is a strong nonlinear function …
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Study of Porous Materials Incorporating Boronate Esters
… esters as secondary building units to form a porous material. COF-18Å has the ability to store gases, high surface areas, good thermal stability, but is susceptible to hydrolysis. Preliminary results show that the covalent organic frameworks have the ability to be repaired, recycled, and …
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The mechanisms involved during the desaturation process of a porous matrix
… of soil suction. Examining the drying process of porous material gave perspective into the development of negative pressures. The drying material was modeled by a regular packed matrix of equal diameter spheres. Configuring the water into the geometric shape of pendular rings simulated the water …
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Phase transition induced deformation in porous media
… phase transitions in equilibrium thermodynamics. Porous, amorphous materials are widely used in everyday life, yet their complex spatial structures lead to unresolved questions for statistical mechanics, both in- and out-of equilibrium. In this thesis I examine the mechanical consequences of …
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The effect of the packing density on the indentation hardness of cohesive-frictional porous materials
… rocks in particular are highly heterogeneous materials which defy a straightforward implementation of the materials science paradigm of microstructure-properties-performance correlation. The application of nanoindentation to natural composites has provided the geomechanics community with a new …
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Subsurface two-photon lithography: improvements and applications
… of three-dimensional structures where the material is uniform throughout. When performing subsurface controllable refractive index via beam exposure (SCRIBE), two-photon lithography is implemented with a porous material as the writing medium, allowing different densities of photoresist to …
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Laboratory investigation of a method for determining in situ saturated hydraulic conductivity
… in situ saturated hydraulic conductivity in porous media. This method requires an accurate measurement of the horizontal port water speed through a section of a borehole packed with a porous material of known hydraulic conductivity. Analytical expressions describing the theoretical basis for …
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Fully coupled CEM/CFD modelling of microwave heating in a porous medium
… results for the microwave heating of a porous material are presented in this paper. Coupled finite difference time domain and finite volume methods are used to solve equations that describe the electromagnetic field and heat and mass transfer in porous media. These equations are …
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Effect of liner thickness on acoustic wave propagation in ducts
… a point-reacting duct liner that consists of a porous facing sheet backed by cellular cavities are derived by examining the wave propagation within the liner. The relation between the derived expression for the liner acoustic admittance and a semi-empirical formula that is widely used in the …
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Implementation of Refractory Foam Technology for Silencing Small IC Engines
… the use of refractory foam, a new class of porous material, for designing effective silencers for small IC engines. The solution must be lightweight, compact, conformable, and capable of handling the rigors of flight. Throughout the course of this research, many silencer designs were …
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Hierarchical Templates and Their Application to Multimodal Porous Materials Fabrication
Hierarchical materials offer great promise for high-performance sensors and catalysis carriers. Well-defined hierarchically porous materials are promising candidates for a wide range of applications relating to biosensors, separations, drug delivery, surface-enhanced Raman scattering (SERS), etc. …
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Experimental study of heat transfer and fluid flow in unsaturated porous media
… and fluid flow behavior in an unsaturated porous medium. The experiment consisted of a bed of homogeneous glass beads packed uniformly in a Lexan rectangular box. A cylindrical heat source was located horizontally in the middle region of the bed and the bed was heated to steady state …
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Random Packs and Their Use in Modeling High Speed Porous Flow
… have been used to model heterogeneous and porous material morphologies during simulations of physical processes such as burning of coal char, convective burning in porous explosives, and regression of solid rocket propellant. Sphere packs have also been used to predict thermo-mechanical …
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High intensity sound in lined ducts
… of the gas motion as well as the acoustic lining material on the propagation and attenuation of sound in two-dimensional and circular ducts of uniform cross sections in the absence of mean flow. The ducts are lined with a point-reacting acoustic material consisting of a porous sheet or of a …
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