A STUDY OF VIBRATIONAL RELAXATION IN CARBON MONOXIDE BY SHOCK-WAVES AND INFRA-RED EMISSION

Temperature measurements have been made with the chromium resonance triplet at 4254, 4274 and 4289 Å, controlled amounts of chromium being introduced in the form of the volatile carbonyl; this method has the advantage that it can be used with explosive mixtures. Measurements of vibrational relaxation time have been made for carbon monoxide between 2200 and 2700°K and of the rate of dissociation of hydrogen in hydrogen + argon mixtures between 2400 and 2800°K. Temperature irregularities in the fronts of shocks through argon or neon are discussed, but no satisfactory explanation for them has been found. Excitation processes in monatomic gases are also examined. The method has been used to study the temperature distribution behind detonations which have been initiated by shocks of various strengths. For ethylene + oxygen detonations the chromium excitation temperature is very high at the front; this is attributed to chemiluminescent excitation in the reaction zone. In carbon monoxide + oxygen detonations initiated by weak shock waves we have observed interesting steps in the temperature behind the front and have explained these as being due to delayed ignition behind the shock and an acceleration of the front leading to detonation after the front has travelled some way along the shock tube.

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Normal interaction of shock waves in the presence of vibrational relaxation

Fluid Dynamics ◽

10.1007/bf01013004 ◽

1977 ◽

Vol 11 (4) ◽

pp. 565-570

Author(s):

V. T. Kireev ◽

N. A. Tikhomirov

Keyword(s):

Shock Waves ◽

Vibrational Relaxation ◽

Interaction Of Shock Waves

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Stimulated and spontaneous far infra-red emission from uniaxially strained gapless Hg1−xCdxTe

Opto-Electronics Review ◽

10.2478/s11772-010-1036-5 ◽

2010 ◽

Vol 18 (3) ◽

Author(s):

S.G. Gasan-Zade ◽

M.V. Strikha ◽

G.A. Shepelskii

Keyword(s):

Electric Field ◽

Impact Ionization ◽

Strong Electric Field ◽

Radiative Transition ◽

Hot Electrons ◽

Acceptor Level ◽

Threshold Values ◽

Red Emission ◽

V Band ◽

Infra Red

AbstractThe intensive far infra-red irradiation in the range of 80–100 μm was observed in uniaxially strained gapless p-Hg1−xCdxTe (MCT) with x = 0.14 in the strong electric field. The inverse occupation in strained MCT is created because the hot electrons distribution occurs in the c-band under impact ionization, while the holes are localized near the v-band top. The probability of band-to-band radiative transition increases dramatically when the acceptor level becomes resonance in the v-band. At threshold values of strain and electric field (P = 2.5–2.7 kbar, E = 50–55 V/cm), increase in irradiation (by 3 orders of magnitude) and increase in current (by 4–6 times) occur.

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