摘要:

In a review the most important results of the Central Institute of Isotope and Radiation Research (ZfI) in the last 5 years are given. Besides the theoretical studies about properties of isotopes and the interaction of ionizing radiation with matter, the application of isotopes in different branches like chemical industry, geology and medicine is presented and the use of radiation processes in diverse fields is described. Furthermore some new results in analytical methods determining radioactive and stable isotopes are revealed. Finally products of radioactive and stable isotopes are reported.

ISSN:0021-1915    

DOI:10.1080/10256018908624174

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

ISSN:0021-1915    

DOI:10.1080/10256018908624175

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

The ion-exchange application of the bidimensional solid/liquid technique for the preparation of different15N-abundances utilizing the isotope exchange system

ISSN:0021-1915    

DOI:10.1080/10256018908624177

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

The experimental measurements of the reflected (albedo) component of the secondary gamma radiation have been carried out for cylindrical samples of graphite, ilmenite limonite concrete and iron of different thicknesses. A collimated beam of neutrons emitted from one of the horizontal channels of the ET-RR-1 reactor have been used. A single stilbene crystal scintillator applying zero crossover technique for the differentiation between gamma and neutron pulses have been utilized. The measured pulse height spectra were transformed to energy spectra. It was shown that the reflected secondary gamma rays increase with the increase of the material thickness then becomes constant. The reflected secondary gamma rays increase also with the increase of the used material density.

ISSN:0021-1915    

DOI:10.1080/10256018908624180

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

The gamma-induced thermoluminescence (TL) in five types of plastics has been studied. The plastics used are Lexan, Makrofol, CA 80-15, LR 115 and CR-39. The result showed that the TL response for Makrofol and Lexan is linear in the range 5 …700 krad, 5 … 3000 krad, respectively. This suggests the possible use of these plastics for gamma dosimetry in the dose range 5 … 3000 krad.

ISSN:0021-1915    

DOI:10.1080/10256018908624181

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

The method of feasible directions is applied to solve some design optimization problems of gamma irradiation facilities and is tested with an example for the two-sided irradiation of a cubic container by one source. A standard mathematical program on the basis of Zoutendijek-algorithm, implemented on a 16 bit personal computer is used. The computing time for one optimal combination calculation is in the range of minutes.

ISSN:0021-1915    

DOI:10.1080/10256018908624182

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

A number of 5-arylazo-2-thiohydantoins (Ia … e) were prepared. The structure of the prepared materials is established by means of correct analytical data, infrared and electronic absorption spectra. Then the materials were subjected to an absorbed energetic γ-ray dose (5.0 × 107rd). The infrared and electronic absorption spectra of each material were measured after γ-irradiation. Upon γ-irradiation a considerable change occurs. Furthermore a sequence for the relative stability of the different dyes against γ-irradiation was established.

ISSN:0021-1915    

DOI:10.1080/10256018908624183

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Thicknesses of gold and silver thin films have been determined by NAA technique. Reasonable agreement with conventional optical method has been obtained, but the lower detection limit in the case of NAA is far better than in the optical method.

ISSN:0021-1915    

DOI:10.1080/10256018908624184

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Ein bedeutendes Problem bei der Herstellung hochreinen Gadoliniums ist die Entfernung von Europium-Spuren. Die Kombination von elektrochemischer Reduktion zu Eu2+und dessen Adsorption an einem frisch hergestellten SrSO4- Niederschlag erweist sich als hochwirksame Methode. Im Labormaβstab konnten Verunreinigungen von 20—100 ppm Europium aus Gadoliniummengen zwischen 8 und 30 g bis auf einen Endwert von < 1 ppm nach Elektrolyse an einer Hg-Elektrode bei < −460 mV in Gegenwart von 500–1200 mg SrSO4nach 25 Stunden Behandlungszeit reduziert werden. Alle anderen Verunreinigungen, einschlieβlich Sr2+, wurden in einem zweiten Schritt mittels Ionenaustausch-chromatographie entfernt. Der Abreicherungseffekt wurde unter Verwendung der Isotope Eu-152/Eu-154 kontrolliert.

ISSN:0021-1915    

DOI:10.1080/10256018908624185

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Im Hinblick auf eine vor Ort Anwendung auf dem Gebiet der Bauwerksdiagnostik stellt die vorliegende Arbeit erste Ergebnissc vor, die unter Ausnutzung der prompten Gammastrahlung erzielt wurden. Dabei werden ausschlieβlich, unelastische Streuprozesse schneller Neutronen an der Probenmatrix betrachtet. Dic Anregung erfolgte mit einer238Pu/Be-Neutronenquelle mit einem Neutronenfluβ von ca. 5 × 107s−1und die Registrierung der prompten Gammastrahlung mit einem NaI(Tl)-Kristall. Besonderes Augenmerk galt den Elementen Mg, Al, Si und Fe als qualitätsbeeinflussende Parameter des Betons.

ISSN:0021-1915    

DOI:10.1080/10256018908624186

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor