Continuous ammonia monitor using a Stark microwave cavity resonator.
An ammonia monitor has been made by using a rectangular Stark microwave cavity tightly coupled through an iris to a Gunn oscillator. The Stark electrode installed inside the cavity is provided with a 100 kHz sinusoidal modulation voltage and a dc sweep voltage. The oscillation of the Gunn diode is tuned with the coupled Stark cavity to a frequency near a J,K=3,3 transition (23870.1 MHz) of ammonia. By fixing the Stark dc bias to a voltage which gives a peak intensity of the derivative output of the electric-resonance signal, ammonia is continuously monitored. An extremely good long-term stability is obtained. The noise level corresponds to 0.08 ppm of ammonia.
Uehara
H
H
Sagami Chemical Research Center, Nishi-Ohnuma, Sagamihara-shi, Kanagawa 229, Japan.
Ijuuin
Y
Y
Morino
Y
Y
Kamidate
T
T
Nakamura
A
A
Imai
H
H