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Mg, Al, Si, P, Ca, Ti, V, Se, Sr and Ba have been analyzed simultaneously in technical calcium carbide using 14 MeV neutron activation analysis. One irradiation and one or two measuring periods were necessary for each sample. Gamma spectra were taken with a high-resolution Ge(Li)-spectrometer, data were processed with a 32 k computer. Seven samples could be analyzed within one day. In order to control the accuracy of the results a multielement reference material was used as a secondary standard. The obtained data were in very good agreement with those of other analysis methods.   相似文献   

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Three experimentally different methods for analysing silicon in steel by activation with fast neutrons are described. By bombardment of28Si with fast neutrons28Al is obtained after a (n, p) reaction.28Al emits a γ-radiation of 1.78 MeV. The difficulty lies in discriminating the 1.78 MeV peak out of the emitted radiation. The first method consists in determining the ratio of the 1.8 MeV peak to the 2.1 MeV peak of an activated iron sample. From this ratio one can deduct the contribution of28Al to the 1.8 MeV peak of a silicon containing sample. The other method of separation makes use of the different half-lives of the 1.78 MeV γ-rays from28Al and the 1.81 MeV γ-rays from56Mn. The direct separation of the peaks with a Ge(Li) detector is the third method. This paper illustrates the possibilities of activation analysis with fast neutrons. For this reason the values measured are compared with the results of chemical analyses.  相似文献   

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Zusammenfassung 8-Hydroxychinolin-Chelate von V, Mo, W, Co, Cr können mit der Hochdruckflüssigkeits-Chromatographie getrennt werden [polare stationäre Phase: Si 60; Eluentien: Tetrahydrofuran/Chloroform (64) bzw. Dioxan/Chloroform (64)]. Die Nachweisgrenzen sind: < 1 ng für V, Mo und Cr; 0,5 ng für Co; 1,5 ng für W.
Separation of the 8-hydroxyquinolinates of V, Mo, W, Co and Cr by HPLC
Summary The oxinates of V, Mo, W, Co and Cr can be separated by HPLG employing Si 60 as stationary phase and either tetrahydrofuran/chloroform (64) or dioxan/chloroform (64) as eluents. Limits of detection are: < 1 ng for V, Mo and Cr; 0.5 ng for Co; 1.5 ng for W.
Ich danke der Deutschen Forschungsgemeinschaft für die Bereitstellung von Geräten und Sachbeihilfen.Mein besonderer Dank gilt Frl. Pohlmann für die Durchführung zahlreicher Meßreihen.  相似文献   

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Zusammenfassung Die Bestimmung der Spurenelemente Cd, Cr, Cu, Fe, Mn und Zn durch flammenlose Atomabsorptionsspektrometrie in einer Graphitrohrküvette nach der Additionsmethode wurde für Reinstwasser, ein standardisiertes Wasser mit einem Gehalt von 100 ppm Ca und 10 ppm Na und für Rheinwasser kritisch überprüft. Dazu wurden jeweils fünf unabhängige Messungen durchgeführt, die Fehler der Einzelmessungen und die Standardabweichungen wurden bestimmt und verglichen.
Precision and accuracy of analytical results in determining the elements Cd, Cr, Cu, Fe, Mn and Zn by flameless AAS
Summary The determination of the trace elements Cd, Cr, Cu, Fe, Mn and Zn by flameless atomic absorption spectrometry in a graphite tube by use of the method of standard addition was critically checked for pure water, standardized water containing 100 ppm of Ca and 10 ppm of Na, and Rhine water. Five independent measurements were made; the individual errors of the measurements and the standard deviations were determined and compared.


Dem Bundesministerium für Forschung und Technologie danken wir für die finanzielle Unterstützung.  相似文献   

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For the determination of trace elements in neutron irradiated, selenium by gamma-ray spectrometry the separation of the matrix activity is often necessary. In model experiments the decontamination of cation and anion impurities from the matrix solution was investigated by the counter current ion migration. After a processing of 3 hrs the trace activities of Co, Cr, Ga, Na and Zn were decontaminated from Se with a factor of >103. For the trace elements As and Te representing the anionic constituents, a decontamination factor of 3·102 was obtained.  相似文献   

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A calculation method of self-shielding coefficients of interesting elements in samples of any forms is given for the neutron activation analysis of cadmium and its compounds. The determination of ten elements in cadmium telluride using radiochemical separation and γ spectrometry is described.   相似文献   

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Zusammenfassung Der Einfluß von verschiedenen Anionen, Komplexbildnern und kolloidalen Substanzen auf die Bestimmung der Spurenelemente Cd, Cr, Cu, Fe, Mn und Zn durch flammenlose Atomabsorption wird unter Verwendung der Additionsmethode überprüft. Dabei wird festgestellt, daß die Abweichungen von den richtigen Werten dann recht hoch sein können, wenn Komplexbildner oder kolloidale Bestandteile in der Lösung vorhanden sind.
Effect of admixtures on the precision and accuracy of analytical results in determining the elements Cd, Cr, Cu, Fe, Mn and Zn by flameless AAS
Summary The influence of various anions, complexing agents and colloidal substances on the determination of the trace elements Cd, Cr, Cu, Fe, Mn and Zn by flameless atomic absorption is investigated by use of the method of standard addition. It is found that the deviations from the correct values can be rather high if complexing agents or colloidal substances are present in the solutions.


Dem Bundesministerium für Forschung und Technologie danken wir für die finanzielle Unterstützung der Arbeit.  相似文献   

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