A method for analysing "P in small aqueous samples by measuring the Cerenkov radiation is described. Centering problems with small sample volumes are eliminated by placing the sample in a polystyrene tube in the scintillation vial. The detection efficiency is high, 54.5 + 0.6% (2 SD) at a sample vol
Measurements of the noise produced by a small office machine
โ Scribed by M.J. Crocker; R.R. Hudson
- Publisher
- Elsevier Science
- Year
- 1969
- Tongue
- English
- Weight
- 284 KB
- Volume
- 2
- Category
- Article
- ISSN
- 0003-682X
No coin nor oath required. For personal study only.
โฆ Synopsis
Measurements of the overall noise level, and of the noise produced by a small office machine in 1/3 octave bands from 100 to 12,500 Hz were made in the Liverpool University reverberation room. The noise produced on the A scale was also measured. From the measurements, the A scale level and the frequency spectrum of the noise expected in a typical lO00ft 3 room with a reverberation time of 1/2 sec were determined. The acoustic power of the machine was also calculated.
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