摘要:

On the basis of quantum chemical model IR laser multiphoton absorption probabilities and corresponding isotope effects for collisionless UF6molecules in the electronic ground state are calculated. Taking into account the detailed fine structure of the spectrum of the pumped mode the isotopic selectivity of the multiphoton excitation process of UF6can be proved theoretically. The results are compared with experimental results and suggest a begin of the quasicontinuum states of UF6at a vibrational level n ≧ 6.

ISSN:0021-1915    

DOI:10.1080/10256018608623631

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

The influence of an initial excitation of a molecular vibrational mode on the photofragmentation process occurring in fragmentation processes in the fields of two lasers (IR + UV) is investigated theoretically. The problem is treated as a modified Franck-Condon transition into the continuum. The calculations indicate that an initial vibrational excitation can lead to higher fragmentation probabilities in agreement with experimental results.

ISSN:0021-1915    

DOI:10.1080/10256018608623632

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

An empirical model is given, which allows a satisfactory description of essential residts of the collisionless mulliphoton dissociation of uranyl compounds by means of an IR laser (e.g. absorption cross section, fluence and frequency dependence of the yield and its isotope effect) with a small mathematical effort. Especially it is possible to explain theoretically the origin of the observed isotope effect and to describe the absorption of laser energy and its redistribution within the other vibrational modes of the molecule.

ISSN:0021-1915    

DOI:10.1080/10256018608623633

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

In tertiary mugmatites from the south of GDR the contents of Na, Fe and 20 trace elements are determined by INAA. For 9 phonolithes and other basaltic rocks mean values and concentration intervals uf the elements determined are represented. Comparison of some results determined parallel with optical analytical methods give average deviations for Fe and Na of approximately 3% and for Ba, Cr and Ni of about 20%. The results of U- and Th-determination are compared by measurements of natural radioactivity. Average deviations run to 10%. The use of Cr, Sc and Th as indicator elements of magmalic differentiation is discussed.

ISSN:0021-1915    

DOI:10.1080/10256018608623634

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

A new rapid analyzer from the series of approved 1TRA devices as developed in the Research Institute of Non-Ferrous Metals Freiberg for single- and multielement analysis in non-ferrous metallurgy is described. ITBA-084 represents an efficient microprocessor-controlled on-line analyzer on the main principles utilized hitherto with success in device engineering (isotope excitation, four-channel modification, balance filter method). A monoboard microcomputer based on U880 provides the central control of the device, allowing extensive analytical programs for matrix correction to be executed. High stability and reproducibility of measured values are achieved by the use of digital peak stabilization. Scintillation probes and proportional counters are used for the detectors. The efficiency of the analyzer is demonstrated and discussed in the light of measured values.

ISSN:0021-1915    

DOI:10.1080/10256018608623635

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Electronic emission detectors used in reactors for the control of the neutron flux density contain rhodium emitter material. By chemical pulping of the emitter it is possible to get102Rh labelled solutions of the spent detectors. The preparation and purification of the solutions are described.

ISSN:0021-1915    

DOI:10.1080/10256018608623636

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

The state of emission spectroscopic15N-analysis is explained on example of the NOI-6e15N-anulyzer. This is an analytical instrument with high operation comfort by computer guidance, digital data acquisition and processing by means of a microcomputer. The15N-abundance can be determined in standard discharge tubes or also in liquid ammonium salt solutions by means of an integrated sample preparation system on 10 μg nitrogen in a short time with a standard-deviation a less than 0.6%.

ISSN:0021-1915    

DOI:10.1080/10256018608623637

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

ISSN:0021-1915    

DOI:10.1080/10256018608623638

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

ISSN:0021-1915    

DOI:10.1080/10256018608623639

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

ISSN:0021-1915    

DOI:10.1080/10256018608623640

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor