Results 1 - 10 of 1559
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[en] An overview of the theory and techniques of radiometric thermometry is presented. The characteristics of thermal radiators (targets) are discussed along with surface roughness and oxidation effects, fresnel reflection and subsurface effects in dielectrics. The effects of the optical medium between the radiating target and the radiation thermometer are characterized including atmospheric effects, ambient temperature and dust environment effects and the influence of measurement windows. The optical and photodetection components of radiation thermometers are described and techniques for the correction of emissivity effects are addressed
[en] Comparison of performances of radiation measuring instruments for special purpose and personal use is presented. The capabilities of Sosna radiometer are shown to measure the dose rate of gamma-radiation, beta-contamination of surfaces and to determine the activity concentration of gamma- and beta-radiation nuclides
[en] It is proposed to register the instant of termination of the electrolytic thinning-down of a foil designed for translucent electron-microscope studies with the help of a radiometer. In this case it will be possible to use not only the light source but also sources of low-intensity soft β- and γ-radiation to register the moment of termination of the thinning-down process
[en] The importance of laser radiation sources in photodetector calibration processes is considered and shown. As an example of that, a recently made work comparing the spectral radiant flux measurement uncertainty of several absolute radiometers is described
[en] The Planck Low Frequency Instrument (LFI) radiometers have been tested extensively during several dedicated campaigns. The present paper reports the principal noise properties of the LFI radiometers. A brief description of the LFI radiometers is given along with details of the test campaigns relevant to determination of noise properties. Current estimates of flight sensitivities, 1/f parameters, and noise effective bandwidths are presented. The LFI receivers exhibit exceptional 1/f noise, and their white noise performance is sufficient for the science goals of Planck.
[en] The cost of hydrometallurgical processing of such uranium ores is high, but it can be reduced by chemical concentration methods. The present article examines the use of radiometry methods for increasing the quality of the ore during extraction and primary processing. A scheme is given for checking the quality of the ore in systems involving selective and mass breakdown of the ore respectively. 6 refs
[en] The principle of operating, construction and software of the new, CMOS-microcomputer based mining radiometer is described. The radiometer is intended for determination of the potential alpha energy concentration and Rn-222 decay products concentration in the air of underground mines. (author). 9 refs, 3 figs
[en] This paper describes the Planck Low Frequency Instrument tuning activities performed through the ground test campaigns, from Unit to Satellite Levels. Tuning is key to achieve the best possible instrument performance and tuning parameters strongly depend on thermal and electrical conditions. For this reason tuning has been repeated several times during ground tests and it has been repeated in flight before starting nominal operations. The paper discusses the tuning philosophy, the activities and the obtained results, highlighting developments and changes occurred during test campaigns. The paper concludes with an overview of tuning performed during the satellite cryogenic test campaign (Summer 2008) and of the plans for the just started in-flight calibration.