Prediction of Effective Elasticity Coefficients of Composite Biofuel

It is suggested that fuel pellets made of composites based on solid plant waste should be considered as stochastic systems that are anisotropic in microvolumes but isotropic in the entire structure, i.e. quasi-isotropic in volume. Based on this hypothesis and the analysis of the known micromechanical models for forecasting physical and mechanical constants of composite materials, the expediency of using the Reuss-Voigt and Hashin-Strickman models to determine the effective elastic coefficients of composite biofuels is substantiated. The results of calculations made on these models for a number of two-component biofuel pellets are given. An experimental evaluation of effective Young's modulus and Poisson's ratio for two-component pellets with "straw + brown coal" composition was carried out. The obtained results of experimentally determined values of coefficients satisfactorily correspond to their calculated values: deviations are up to 26%. The Reuss-Voigt model was used in the calculations because the conditions required for the application of the Hashin-Strickman model are not met for composite pellets consisting of straw and brown coal. The results of the study will be useful in calculating or selecting press equipment for the production of quality fuel pellets from composites based on solid plant waste.

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Fabrication Strategies and Thermal Conductivity Assessment of High Density UO2 Pellet Incorporated with SiC

MRS Proceedings ◽

10.1557/opl.2012.1423 ◽

2012 ◽

Vol 1444 ◽

Author(s):

Sunghwan Yeo ◽

Edward Mckenna ◽

Ronald Baney ◽

Ghatu Subhash ◽

James Tulenko

Keyword(s):

Thermal Conductivity ◽

Conductivity Measurement ◽

Sintered Pellet ◽

Fuel Pellets ◽

Plasma Sintering ◽

Composite Pellets ◽

Spark Plasma ◽

Water Reactors ◽

Nuclear Fuel Pellets ◽

Enhanced Thermal Conductivity

ABSTRACTEnhanced thermal conductivity oxide fuels offer increases in both safety and efficiency of commercial light water reactors. Low-temperature oxidative sintering and Spark Plasma Sintering (SPS) techniques have been used to produce UO2-SiC composite pellets. Oxidative sintering performed for 4 hours at 1200∼1600oC and SPS was employed only for 5 mins at the same temperature. While oxidative sintering failed to achieve enhanced thermal conductivity, the SPS sintered pellet obtained promising features such as higher density, better interfacial contact, and reduced chemical reaction. Thermal conductivity measurement at 100oC, 500oC, and 900oC revealed maximum 62% higher thermal conductivity value, when compared to UO2 pellets, in SPS sintered UO2-10vol% SiC composite pellet. The result shows that the SPS technique is required to sinter UO2-SiC nuclear fuel pellets with a high value of thermal conductivity.

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Influence of coal composition on the release of Na-, K-, Cl-, and S-species during the combustion of brown coal

Fuel ◽

10.1016/j.fuel.2007.01.030 ◽

2007 ◽

Vol 86 (15) ◽

pp. 2275-2282 ◽

Cited By ~ 47

Author(s):

H OLESCHKO ◽

A SCHIMROSCZYK ◽

H LIPPERT ◽

M MULLER

Keyword(s):

Brown Coal ◽

Coal Composition

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Stimulation of Low-Temperature Dissolution of Organic Matter of Brown Coal, Composition of Bitumoids

10.2991/ahcps.k.211004.016 ◽

2021 ◽

Author(s):

Sergey Zherebtsov ◽

Kirill Shpakodraev ◽

Natalia Malyshenko ◽

Konstantin Votolin ◽

Zinfer Ismagilov

Keyword(s):

Organic Matter ◽

Low Temperature ◽

Brown Coal ◽

Coal Composition ◽

Stimulation Of

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Spectroscopic Observations of Visual Double Stars

International Astronomical Union Colloquium ◽

10.1017/s0252921100027536 ◽

1965 ◽

Vol 5 ◽

pp. 109-111

Author(s):

Frederick R. West

Keyword(s):

Radial Velocity ◽

High Dispersion ◽

Velocity Difference ◽

Spectrograph Slit ◽

Spectroscopic Observations ◽

Double Stars ◽

Visual Double Stars ◽

Relative Orbit ◽

Two Component ◽

Star Images

There are certain visual double stars which, when close to a node of their relative orbit, should have enough radial velocity difference (10-20 km/s) that the spectra of the two component stars will appear resolved on high-dispersion spectrograms (5 Å/mm or less) obtainable by use of modern coudé and solar spectrographs on bright stars. Both star images are then recorded simultaneously on the spectrograph slit, so that two stellar components will appear on each spectrogram.

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A technique for protecting delicate specimens during processing

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100156894 ◽

1989 ◽

Vol 47 ◽

pp. 982-983

Author(s):

R.J. Mount ◽

R.V. Harrison

Keyword(s):

Basilar Membrane ◽

Low Cost ◽

Organ Of Corti ◽

Region Of Interest ◽

Sensory Epithelium ◽

Physical Damage ◽

Air Drying ◽

Specimen Handling ◽

Two Component

The sensory end organ of the ear, the organ of Corti, rests on a thin basilar membrane which lies between the bone of the central modiolus and the bony wall of the cochlea. In vivo, the organ of Corti is protected by the bony wall which totally surrounds it. In order to examine the sensory epithelium by scanning electron microscopy it is necessary to dissect away the protective bone and expose the region of interest (Fig. 1). This leaves the fragile organ of Corti susceptible to physical damage during subsequent handling. In our laboratory cochlear specimens, after dissection, are routinely prepared by the O-T- O-T-O technique, critical point dried and then lightly sputter coated with gold. This processing involves considerable specimen handling including several hours on a rotator during which the organ of Corti is at risk of being physically damaged. The following procedure uses low cost, readily available materials to hold the specimen during processing ,preventing physical damage while allowing an unhindered exchange of fluids.Following fixation, the cochlea is dehydrated to 70% ethanol then dissected under ethanol to prevent air drying. The holder is prepared by punching a hole in the flexible snap cap of a Wheaton vial with a paper hole punch. A small amount of two component epoxy putty is well mixed then pushed through the hole in the cap. The putty on the inner cap is formed into a “cup” to hold the specimen (Fig. 2), the putty on the outside is smoothed into a “button” to give good attachment even when the cap is flexed during handling (Fig. 3). The cap is submerged in the 70% ethanol, the bone at the base of the cochlea is seated into the cup and the sides of the cup squeezed with forceps to grip it (Fig.4). Several types of epoxy putty have been tried, most are either soluble in ethanol to some degree or do not set in ethanol. The only putty we find successful is “DUROtm MASTERMENDtm Epoxy Extra Strength Ribbon” (Loctite Corp., Cleveland, Ohio), this is a blue and yellow ribbon which is kneaded to form a green putty, it is available at many hardware stores.

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