Preliminary study of the importance of hydrothermal reactions on the temperature history of a hot, dry rock geothermal reservoir

The spatially and temporally resolved evaporation phenomena of a slowly evaporating water droplet are investigated using a microfabricated gold heater array consisting of 32 linear heater elements (100 μm wide and 15 mm long, each). Each of the gold microheater elements works both as a temperature sensor and as a heater. The experiment is performed under a constant voltage mode to examine the spatially resolved temperature history of the droplet contact surface for a period starting at initial contact with the heater and lasting to the point of complete dryout. The raw data obtained from the linear array have been tomographically deconvolved so that the radial temperature profile can be determined assuming a circular droplet contact surface.

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The Relation of Vibrator Surface Area and Static Application Force to the Vibrator-to-Head Coupling

Journal of Speech and Hearing Research ◽

10.1044/jshr.1104.805 ◽

1968 ◽

Vol 11 (4) ◽

pp. 805-810 ◽

Cited By ~ 9

Author(s):

E. R. Nilo

Keyword(s):

Young Adult ◽

Surface Area ◽

Unit Area ◽

Bone Conduction ◽

Pressure Force ◽

Adult Men ◽

Surface Areas ◽

History Of ◽

Preliminary Study ◽

Bone Conduction Hearing

Twelve young adult men with normal hearing and no history of ear disease took part in our study of the relation of vibrator surface area and static application force to the vibrator-to-head coupling. For vibrator surface areas of 1.125, 2.25, and 4.5 cm 2 coupled to the forehead under static forces of 150, 300, and 600 gm, monaural thresholds of bone-conduction hearing were determined at frequencies 250, 500, 1000, and 2000 Hz. With surface area constant, threshold improvement was frequency dependent. It decreased with increasing frequency until at 2000 Hz it was minimal. In contrast to this, with force constant, the influence of surface area was observed to begin at 2000 Hz. Preliminary study suggests this influence would extend to 4000 Hz. In view of the respective influence of application force and surface area to bone-conduction hearing, equating vibrator-to-head coupling on the basis of pressure (force per unit area), when there are two or more vibrators, may not represent an adequate control.

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A preliminary study of the taxane chemistry and natural history of the Mexican yew, Taxus globosa Schltdl.

Botanical Sciences ◽

10.17129/botsci.1672 ◽

2017 ◽

pp. 119

Author(s):

Melvin J. Shemluck ◽

Eduardo Estrada ◽

Robert Nicholson ◽

Susan W. Brobst

Keyword(s):

Natural History ◽

Chemical Study ◽

Morphological Comparison ◽

Average Percentage ◽

Baccatin Iii ◽

History Of ◽

Ecological Habitat ◽

Preliminary Study ◽

Taxus Globosa ◽

Intrapopulational Variation

This paper represents a preliminary study of the botany, natural history and taxane chemistry of the Mexican yew, Taxus globosa Schltdl. Taxonomic history, morphological comparison to other North American species and ecological habitat are discussed. Chemical study involved leaf and twig material from forty-nine plants from three localities in Mexico. Levels of taxol, cephalomannine and baccatin III were determined by HPLC analysis. Intrapopulational variation was found to be very high while mean taxane levels for each of the three populations were very similar. The average percentage of taxol in leaves of T. globosa is higher than in all other species of Taxus (0.0121% dry wt.).

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Optimization of Laser Hardening Processes for Industrial Parts With Complex Geometry via Predictive Modeling

ASME 2009 International Manufacturing Science and Engineering Conference, Volume 2 ◽

10.1115/msec2009-84012 ◽

2009 ◽

Cited By ~ 4

Author(s):

Neil S. Bailey ◽

Yung C. Shin

Keyword(s):

Phase Transformation ◽

Thermal Model ◽

Complex Geometry ◽

Solid Phase ◽

Three Dimensional ◽

Laser Hardening ◽

Temperature History ◽

Temperature Phase ◽

Laser Systems ◽

History Of

A predictive laser hardening model for industrial parts with complex geometric features has been developed and used for optimization of hardening processes. A transient three-dimensional thermal model is combined with a three-dimensional kinetic model for steel phase transformation and solved in order to predict the temperature history and solid phase history of the workpiece while considering latent heat of phase transformation. Further, back-tempering is also added to the model to determine the phase transformation during multitrack laser hardening. The integrated model is designed to accurately predict temperature, phase distributions and hardness inside complex geometric domains. The laser hardening parameters for two industrial workpieces are optimized for two different industrial laser systems using this model. Experimental results confirm the validity of predicted results.

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Predicting strength of additively manufactured thermoplastic polymer parts produced using material extrusion

Rapid Prototyping Journal ◽

10.1108/rpj-02-2017-0026 ◽

2018 ◽

Vol 24 (2) ◽

pp. 321-332 ◽

Cited By ~ 14

Author(s):

Joseph Bartolai ◽

Timothy W. Simpson ◽

Renxuan Xie

Keyword(s):

Infrared Imaging ◽

Acrylonitrile Butadiene Styrene ◽

Temperature History ◽

Interface Temperature ◽

Fused Filament Fabrication ◽

Content Type ◽

Material Extrusion ◽

Rheological Data ◽

History Of ◽

Butadiene Styrene

Purpose The weakest point in additively manufactured polymer parts produced by material extrusion additive manufacturing (MEAM) is the interface between adjacent layers and deposition toolpaths or “roads”. This study aims to predict the mechanical strength of parts by utilizing a novel analytical approach. Strength predictions are made using the temperature history of these interfaces, polymer rheological data, and polymer weld theory. Design/methodology/approach The approach is validated using experimental data for two common 3D-printed polymers: polycarbonate (PC) and acrylonitrile butadiene styrene (ABS). Interface temperature history data are collected in situ using infrared imaging. Rheological data of the polycarbonate and acrylonitrile butadiene styrene used to fabricate the fused filament fabrication parts in this study have been determined experimentally. Findings The strength of the interfaces has been predicted, to within 10% of experimental strength, using polymer weld theory from the literature adapted to the specific properties of the polycarbonate and acrylonitrile butadiene styrene feedstock used in this study. Originality/value This paper introduces a novel approach for predicting the strength of parts produced by MEAM based on the strength of interfaces using polymer weld theory, polymer rheology, temperature history of the interface and the forces applied to the interface. Unlike methods that require experimental strength data as a prediction input, the proposed approach is material and build orientation agnostic once fundamental parameters related to material composition have been determined.

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