摘要:

A review describing the present possibilities of thermoluminescence (TL) in the investigation of polymers is presented in this paper. It is divided into four sections: (1) Theoretical fundamentals of thermoluininescence in organic solids; (2) Experimental aspects of TL; (3) Application of TL in the polymer research, generally; (4) TL-studies of selected problems. Thereby the emphasis is put on the analysis of radiation physical and radiation chemical processes in polymers.

ISSN:0021-1915    

DOI:10.1080/10256018808623993

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

Neutron irradiation effects on the electrical properties of the silicon devices (IMPATT diode and solar cell) have been studied in detail. A neutron fluence of 8.45 × 1015neutrons/cm2was found to cause a permanent damage on the silicon IMPATT diode leading to a pronounced increase in the reverse saturation current and reverse avalanche breakdown voltage, as well as to a change in the I-V-relationship. In addition, the temperature coefficient of the device breakdown voltage becomes negative. Under the same neutron fluence exposure, silicon solar cell looses most of its output characteristics. Increasing the neutron fluence up to 1.872 × 1018neutrons/cm2, both devices loose their characteristic features as rectifying de,ices and behave as linear restistances Neutron activation of the elemental constitution of the devices implies the possibility of transforming them to a radioactive sources.

ISSN:0021-1915    

DOI:10.1080/10256018808623994

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

A theoretical study has been carried out on the effect of Radiation upon the electrical properties of silicon power diodes. Computer program “PDIORAD” is developed to solve the diode equations and to introduce the operating conditions and radiation effects upon its parameters. Temperature increase interrupts the electrical properties of the diode in the direction of drop voltage decrease across the p-n junction. The model is analyzed under the influence of different radiation type (gamma-rays, neutrons, protons and electrons) with various dose levels and energies. The carriers diffusion length are seriously affected leading to a large increase in the forward voltage. These effects are found to be function of radiation type, fluence and energy.

ISSN:0021-1915    

DOI:10.1080/10256018808623995

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

This paper presents results of a study carried out in order to assess the applicability of32Si for groundwater dating. Measurements of32Si in soil samples of the unsaturated zone, of drainage waters and plant material give a basis for estimating the32Si initial concentration in groundwater. Different aquifers with groundwater of young and moderate ages have been selected for groundwater studies. For obtaining independent age information tritium was found to be a suitable reference isotope. A quantitative interpretation of the32Si data is generally complicated by geochemical processes, preferably in the unsaturated zone. Favourable conditions concerning the use of32Si in hydrogeology seem to exist in phreatic sandy aquifers, in limestone aquifers, and, depending on the thickness and composition of the unsaturated zone, in sandstone aquifers. Further improvements of the32Si method needs a better understanding of the geochemical processes affecting this isotope.

ISSN:0021-1915    

DOI:10.1080/10256018808623996

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

Solid State Nuclear Track Detectors have been used to measure the thermal, intermediate and fast neutron fluxes from a 5 Ci Am-Be neutron source, inside a tissue-equivalent phantom. The absorbed dose and the equivalent dose were calculated by using the fluence-dose conversion factors, as well as the related quality factors. The results of the experiment show that the neutron flux, for intermediate and thermal neutrons was higher than that for fast neutrons. The contribution of thermal and fast dose is lower relative to that for intermediate neutrons.

ISSN:0021-1915    

DOI:10.1080/10256018808623997

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

ISSN:0021-1915    

DOI:10.1080/10256018808623998

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor