摘要:

This paper reviews some modern applications of the platinum group elements, mainly Ir and Os, in identifying and studying extraterrestrial materials, e.g. study of impact events resulting in biological mass extinctions in the earth's evolution, identification of cosmic dust, tracing of parent body of meteoritic craters on the earth's surface, searching for extrasolar components in the solar system, estimation of fluxes of extraterrestrial matters, etc. Also various representative neutron activation analysis methods developed for these purposes are summarized.

ISSN:0021-1915    

DOI:10.1080/10256018808623970

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

207Bi was detected in environmental samples and was studied in relation to the radionuclides produced by nuclear explosion tests. A nearly linear relationship between207Bi and137Cs was found while no such relationship was found between207Bi and144Ce. The207Bi radioactivity was mainly ascribed to the old H-bomb tests which were terminated by early 1960's. Model calculation was carried out to estimate relative importance of three possible routes forming the radio-nuclide207Bi. Among them206, 207Pb(d, xn)207Bi reaction was found more important than the other two.

ISSN:0021-1915    

DOI:10.1080/10256018808623971

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

Application of radioanalytical techniques in cosmochemistry developed in the laboratories of the Institute for Geochemistry of the University of Vienna are presented. The techniques described reflect the basic idea to obtain a maximum of information on a minimum of sample available by using quantitative separation procedures to avoid time consuming recovery determinations. It should be mentioned that these radiochemical cycles are nearly always combined with series of nondestructive analyses by short-time irradiations to fulfill the supposition mentioned.

ISSN:0021-1915    

DOI:10.1080/10256018808623972

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

Am 28. Juli 1988 ist der 20. Todestag von Otto Hahn. Vor 50 Jahren hat Otto Hahn mit seinen Mitarbeitern den Zerfall des radioaktiven Rubidiums mit Hilfe einer geologisch alten, rubidiumreichen Glimmerprobe aufgeklärt und mittels der “geologischen” Methode die Halbwertszeit des87Rb bestimmt. Er diskutierte im Einzelnen die Möglichkeit der Altersbestimmung mit dem87Rb–87Sr-Paar und führte erste Datierungen an Rb-reichen Proben (Lepidolith, Polluzit) durch. Es werden Prinzip und Entwicklungsetappen der Rb–Sr-Altersbestimmungsmethode erörtert und einige Anwendungsbeispiele skizziert.

ISSN:0021-1915    

DOI:10.1080/10256018808623973

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

Nuclear analytical techniques, like neutron activation analysis and passive gamma spectrometry, have been adjusted to cover a variety of applications, like exploration of mineral and energy resources, geochemistry, environmental control, biomedicine, industrial and agricultural quality control, archaeometry a.o. For certain applications, like nuclear safeguards analysis and reference material certification of uranium samples, special techniques based on the delayed neutron counting method have been developed in order to achieve the required accuracy.

ISSN:0021-1915    

DOI:10.1080/10256018808623974

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

The article informs about the way of PIXE application in the Czechoslovakian aeroecological research. The external beam PIXE set-up in Prague and the programme of the laboratory is described. The examples of the results are added from the fields of aerosol, blood and hair analyses.

ISSN:0021-1915    

DOI:10.1080/10256018808623975

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

ISSN:0021-1915    

DOI:10.1080/10256018808623976

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

ISSN:0021-1915    

DOI:10.1080/10256018808623977

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

ISSN:0021-1915    

DOI:10.1080/10256018808623978

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor