Annealing time dependence at very high temperature of electric arc-induced long-period fibre gratings

2002 ◽  
Vol 38 (10) ◽  
pp. 449 ◽  
Author(s):  
G. Humbert ◽  
A. Malki
Keyword(s):  
High Temperature ◽  
Time Dependence ◽  
Annealing Time ◽  
Electric Arc ◽  
Long Period ◽  
Very High

Very-high-temperature stable CO2-laser-induced long-period fibre gratings

1999 ◽  
Vol 35 (9) ◽  
pp. 740 ◽  
Author(s):  
D.D. Davis ◽  
T.K. Gaylord ◽  
E.N. Glytsis ◽  
S.C. Mettler
Keyword(s):  
High Temperature ◽  
Co2 Laser ◽  
Long Period ◽  
Very High

scholarly journals II. On the reversal of the lines of metallic vapours. No. V

1879 ◽  
Vol 28 (190-195) ◽  
pp. 367-372 ◽  
Keyword(s):  
High Temperature ◽  
Electric Arc ◽  
Tubular Part ◽  
Long Time ◽  
Very High

Since our last communication we have continued our experiments, using the electric arc as a source of heat, in lime and in carbon crucibles as described before. Success depends on the getting a good stream of vapour in the tubular part of the crucible. This is easily attained in the lime crucibles, which quickly reach a very high temperature, but are very soon destroyed; not so certainly in the carbon crucibles, which are good conductors of heat. The latter, however, last for a very long time.

Death of Salmon and Trout with High Temperature

1942 ◽  
Vol 5c (5) ◽  
pp. 485-501 ◽  
Author(s):  
A. G. Huntsman
Keyword(s):  
High Temperature ◽  
Time Of Day ◽  
Dew Point ◽  
Critical Periods ◽  
Moist Air ◽  
Cool Water ◽  
Long Period ◽  
Deep Channel ◽  
Artificial Freshets ◽  
Very High

Deaths in Moser river, N.S., in 1939 were at time of day, on days, and in locality with highest water temperature. Symptoms were loss of sensitivity to light and very rapid breathing with recovery therefrom in cool water; otherwise followed by loss of equilibrium and cessation of breathing with death. Freshly run grilse died at about 29.5 °C. and acclimated grilse at about 30.5°. Large salmon died first and parr survived. In experiment, the latter died between 32.9 and 33.8°, the smallest at the highest point. Death is considered due directly to temperature.Rainfall after long period of drought brought the salmon from the sea into the river to die where water was shallowest and without cascades, therefore warmest. The very high temperatures and deaths occurred in afternoon from sun's heat and at ends of periods of days with moist air from the ocean and mounting water temperatures, dew point temperatures and mimimal air temperatures.Prevention is seen possible by bringing fish in early with artificial freshets, by constructing low dams to create deep pools and cascades, by making a deep channel or by raising level at critical periods with stored water.

Use of LaB6 for a High Quality, Small Energy Spread Beam in an Electron Velocity Spectrometer

1976 ◽  
Vol 34 ◽  
pp. 534-535 ◽  
Author(s):  
P. E. Batson ◽  
C. H. Chen ◽  
J. Silcox
Keyword(s):  
High Temperature ◽  
Energy Resolution ◽  
Electron Velocity ◽  
Electronic Excitations ◽  
Small Energy ◽  
Small Intensity ◽  
Good Energy ◽  
Spectrometer System ◽  
Electron Energy Loss ◽  
Very High

Electron energy loss experiments combined with microscopy have proven to be a valuable tool for the exploration of the structure of electronic excitations in materials. These types of excitations, however, are difficult to measure because of their small intensity. In a usual situation, the filament of the microscope is run at a very high temperature in order to present as much intensity as possible at the specimen. This results in a degradation of the ultimate energy resolution of the instrument due to thermal broadening of the electron beam.We report here observations and measurements on a new LaB filament in a microscope-velocity spectrometer system. We have found that, in general, we may retain a good energy resolution with intensities comparable to or greater than those available with the very high temperature tungsten filament. We have also explored the energy distribution of this filament.

TEM study of boron additions to cobalt aluminide

1988 ◽  
Vol 46 ◽  
pp. 546-547
Author(s):  
Gerald B. Feldewerth
Keyword(s):  
High Temperature ◽  
Turbine Engines ◽  
Major Drawback ◽  
University Of Missouri ◽  
Specific Strength ◽  
Aerospace Applications ◽  
Wide Range ◽  
Ordered Alloys ◽  
The University ◽  
Very High

In recent years an increasing emphasis has been placed on the study of high temperature intermetallic compounds for possible aerospace applications. One group of interest is the B2 aiuminides. This group of intermetaliics has a very high melting temperature, good high temperature, and excellent specific strength. These qualities make it a candidate for applications such as turbine engines. The B2 aiuminides exist over a wide range of compositions and also have a large solubility for third element substitutional additions, which may allow alloying additions to overcome their major drawback, their brittle nature.One B2 aluminide currently being studied is cobalt aluminide. Optical microscopy of CoAl alloys produced at the University of Missouri-Rolla showed a dramatic decrease in the grain size which affects the yield strength and flow stress of long range ordered alloys, and a change in the grain shape with the addition of 0.5 % boron.

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