scholarly journals (U-Th)/He Thermochronology of the Ottawa Embayment, Eastern Canada: The Temperature-Time History of an Ancient, Intracratonic Rift Basin

2017 ◽  
Vol 125 (6) ◽  
pp. 659-680 ◽  
Author(s):  
R. A. Hardie ◽  
D. A. Schneider ◽  
J. I. Garver
Keyword(s):  
Time History ◽  
Rift Basin ◽  
Eastern Canada ◽  
History Of ◽  
Temperature Time

Run-on in Gasoline Engines

1968 ◽  
Vol 183 (1) ◽  
pp. 21-51 ◽  
Author(s):  
W. S. Affleck
Keyword(s):  
Combustion Chamber ◽  
Time History ◽  
Spontaneous Ignition ◽  
Research Octane Number ◽  
Gasoline Engines ◽  
Engine Cooling ◽  
History Of ◽  
Valve Overlap ◽  
Temperature Time ◽  
Small Valve

When the ignition of a car engine is switched off, the engine normally comes to rest within a few revolutions but, occasionally, it may continue to fire erratically for a few seconds or longer. This phenomenon is known as run-on and, for the majority of European engines, is the result of spontaneous ignition of the fuel-air mixture in the combustion chamber. Part 1 of this paper describes experiments in a single-cylinder research engine which have been made to establish the principles controlling run-on. In particular the effects of air/fuel ratio, the nature of the fuel and the pressure-temperature-time history of the fuel-air mixture in the combustion chamber have been studied, as it is known that these factors play an important part in spontaneous ignition in experiments in laboratory vessels. From these observations it has been possible to formulate a theoretical model of the run-on process which explains the salient features of the phenomenon. In particular, it shows how the gradual cooling of the engine limits the duration of run-on and also how the duration of run-on may be considered as a measure of the extent to which fuel or engine factors must be altered to eliminate run-on. Part 2 describes the application of these principles to car engines using normal commercial-type fuels. It is concluded that the following are important features in the control of run-on: the use of fuel of sufficiently high Research octane number, minimum opening of throttle at idle, sufficient time for cooling of the combustion chamber before the ignition is switched off, efficient engine cooling, and small valve overlap. Current devices for reducing exhaust emissions are likely, through their effects on these features, to increase the tendency of an engine run-on. Combustion chamber deposits, though, appear to have little influence.

scholarly journals Moving the pulsed heating technique beyond monolithic specimens: Experiments with coated wires

2001 ◽  
Vol 16 (8) ◽  
pp. 2421-2428 ◽  
Author(s):  
D. Josell ◽  
D. Basak ◽  
J. L. McClure ◽  
U. R. Kattner ◽  
M. E. Williams ◽  
...  
Keyword(s):  
Single Phase ◽  
Time History ◽  
Standard Technique ◽  
Black Body ◽  
Spectral Emissivity ◽  
Melting Temperatures ◽  
Pulsed Heating ◽  
History Of ◽  
Coated Wires ◽  
Temperature Time

Pulsed heating experiments that measure high-temperature thermophysical properties using pyrometric measurement of the temperature–time history of metal specimens rapidly heated by passage of electric current have a 30-year history at the National Institute of Standards and Technology. In recent years, efforts have been made to move beyond the limitations of the standard technique of using costly, black-body geometry specimens. Specifically, simultaneous polarimetry measurement of the spectral emissivity has permitted study of sheet and wire specimens. This paper presents the results of two efforts to expand beyond the macroscopically monolithic, single-phase materials of all previous studies. In the first study the melting temperatures of coatings, including Ti and Ti(Al) alloys, deposited on higher melting Mo substrates are measured. In the second study the melting temperatures of substrates, Ti and Cr, covered by higher melting W and Mo coatings are measured.

Residual Stresses During Coating Generation: Plasma Sprayed Alumina Coating on XC38 Measurements and Calculations

1998 ◽  
Author(s):  
A.C. Leger ◽  
A. Haddadi ◽  
B. Pateyron ◽  
G. Delluc ◽  
A. Grimaud ◽  
...  
Keyword(s):  
Residual Stresses ◽  
Time History ◽  
Alumina Coating ◽  
Thin Coatings ◽  
Preheating Temperature ◽  
History Of ◽  
Substrate Preheating ◽  
Plasma Sprayed ◽  
Thick Coatings ◽  
Temperature Time

Abstract A simplified ID model has been developed to calculate the temperature time history of alumina layering splats. The splats were obtained by plasma spraying alumina fused and crushed particles (- 45 + 22 µm). The model has shown that for more than 160-200 µm layered splats the solidification time is over 7-10 µs, When spraying thin passes (ep < 15 µm) each splat cools down to substrate preheating temperature before next splat impacts. On the contrary for thick passes (ep = 60 or 180 µm), after depositing a certain thickness (between 160 and 200 µm) depending on spraying conditions, the temperature of the splats never drops below 800-900 K (mean splat temperature). In this case nucleation occurs after flattening is completed. Such conditions allow a columnar growth through the layered splats of each pass and successive passes. The study of the corresponding stresses (quenching σq and expansion mismatch) generated when spraying alumina on XC38 sheet was measured by following continuously the bending of a beam. The comparison of the measurements with the results of a ID model developed by Tsui and Clyne has allowed to calculate the coating Young's modulus Ed and the residual stresses difference at the interface. For thin coatings σq and Ed increase with preheating temperature. For thick coatings the values of Ed and σq are lower than the highest ones of thin coatings. This is probably due to stress relaxation by cracks propagation, the quenching and expansion mismatch stresses increasing with the increasing mean splat temperature.

Variation of antiphase domain size in omphacite: A tool to determine the temperature–time history of eclogites revisited

2003 ◽  
Vol 88 (8-9) ◽  
pp. 1300-1311 ◽  
Author(s):  
Frank E. Brenker ◽  
Wolfgang Friedrich Müller ◽  
Gerhard P. Brey
Keyword(s):  
Time History ◽  
Domain Size ◽  
Antiphase Domain ◽  
History Of ◽  
Temperature Time

scholarly journals Temperature-time history of subducted continental crust, Mount Olympos Region, Greece

Tectonics ◽  
1990 ◽  
Vol 9 (5) ◽  
pp. 1165-1195 ◽  
Author(s):  
Elizabeth R. Schermer ◽  
Daniel R. Lux ◽  
B. Clark Burchfiel
Keyword(s):  
Continental Crust ◽  
Time History ◽  
History Of ◽  
Temperature Time

Dating microstructures by the 40Ar/39Ar step-heating technique: Deformation–pressure–temperature–time history of the Penninic Units of the Western Alps

Lithos ◽  
2009 ◽  
Vol 113 (3-4) ◽  
pp. 801-819 ◽  
Author(s):  
Marco Beltrando ◽  
Gordon S. Lister ◽  
Marnie Forster ◽  
W. James Dunlap ◽  
Geoff Fraser ◽  
...  
Keyword(s):  
Time History ◽  
Western Alps ◽  
Step Heating ◽  
History Of ◽  
Temperature Time

The Thermal Properties of Human Blood during the Freezing Process

1973 ◽  
Vol 95 (2) ◽  
pp. 246-249 ◽  
Author(s):  
F. C. Wessling ◽  
P. L. Blackshear
Keyword(s):  
Thermal Conductivity ◽  
Thermal Properties ◽  
Water Solution ◽  
Time History ◽  
Steel Tube ◽  
Ice Crystals ◽  
Freezing Process ◽  
Stainless Steel Tube ◽  
History Of ◽  
Temperature Time

This paper presents calculations of the density, thermal conductivity, and enthalpy of blood during the freezing process. The calculations are based upon the premise that blood freezes similarly to a mixture of fats, proteins, and sodium chloride in a water solution and freezes so that ice crystals align themselves with the direction of heat flow. The properties were checked by calculating the theoretical temperature–time history of blood freezing in a Teflon-coated stainless-steel tube and comparing the results with experiments. The agreement was within 10 percent over the entire ranges of temperature and time. Hence the derived thermal properties are concluded to be good approximations to the real properties.

Influence of Hot and Cold Storage-Loads on the Refrigerated-Space Temperature of a Cooling Complex

1959 ◽  
Vol 81 (4) ◽  
pp. 339-347
Author(s):  
Carl F. Kayan
Keyword(s):  
Cold Storage ◽  
Energy Transport ◽  
Time History ◽  
Experimental Simulation ◽  
Transient Effect ◽  
Space Cooling ◽  
History Of ◽  
System 1 ◽  
Warehouse Operations ◽  
Temperature Time

Of particular interest in cold-storage warehouse operations is the influence on the space-temperature-time history of a “hot” load of goods suddenly introduced into the refrigerated zone of an insulated structure. The zone may be completely empty, or partially occupied by warehouse goods already down in temperature. Of further interest is the ultimate effect of the transient load on the performance of other components of the system, such as the connected space-cooling heat exchanger. In previous work in this realm by the author on the behavior of the over-all complex, the studies have included the various heat-exchange and machine energy-transport equipments of the system [1]. Whereas in the earlier paper the transient effect was explored via calculation methods, in the study of the problem in this paper experimental simulation methods are employed entirely, using pilot process-prototype transient-elements.

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