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131.
Summary Strontium showed a high atomic emission in a molybdenum microtube. The addition of hydrogen in the argon gas atmosphere served to increase the atomic emission. No interferences from less than 5 ng of potassium, calcium and magnesium were found. Other elements also had no interferences at the concentration levels usually found in biological samples. Samples were digested with nitric acid in a Uni-Seal decomposition vessel. The results obtained showed good agreement with the certified values. Atomic emission spectrometry with a molybdenum microtube atomizer permits a simple and sensitive determination of strontium in biological samples (coefficient of variation 2.5% for 10 pg Sr).
This work was supported by the Ministry of Education, Science and Culture of Japan through a Grant-in-Aid for Special Project Research. 相似文献
Strontiumbestimmung in biologischem Material durch Atomemissions-Spektrometrie mit elektrothermischer Atomisierung
Zusammenfassung Eine hohe Atomemission wurde für Strontium bei Verwendung einer Molybdän-Mikroröhre beobachtet. Durch Wasserstoffzusatz zum Argon konnte sie noch weiter erhöht werden. Weniger als 5 ng K, Ca und Mg verursachen keine Störung. Andere Elemente stören nicht in den Konzentrationsbereichen, wie sie üblicherweise in biologischen Materialien vorkommen. Der Aufschluß der Proben wurde mit Salpetersäure in Uni-Seal-Gefäßen vorgenommen. Die erhaltenen Werte stimmten gut mit zertifizierten Daten überein. Die vorgeschlagene Methode ermöglicht eine einfache und empfindliche Strontiumbestimmung in biologischen Proben (Variationskoeffizient 2,5% bei 10 pg Sr).
This work was supported by the Ministry of Education, Science and Culture of Japan through a Grant-in-Aid for Special Project Research. 相似文献
132.
133.
The phonon dispersion relations of 00σT branch were measured for Ni95Pt5 and Ni70Pt30. The dispersion curves breaks up into two branches. Th general shape and its concentration dependence can be explained qualitatively by Taylor's coherent potential approximation theory. 相似文献
134.
Yoshio Teki Takeji Takui Mitsuru Hirai Koichi Itoh Hiizu Iwamura 《Chemical physics letters》1982,89(3):263-267
Optically detected ENDOR and electron—nuclear—nuclear triple resonance of 17O were measured via phosphorescence from 3(nπ*) benzil in benzophenone-d10 crystals at high magnetic field. The n and π* spin densities on the oxygen atom are 0.201 and 0.092, respectively, the angle between the two CO bonds being 150°. 相似文献
135.
136.
Water content distribution in a polymer electrolyte membrane for advanced fuel cell system with liquid water supply 总被引:2,自引:0,他引:2
To better understand the operation of a new fuel cell design, we used magnetic resonance imaging (MRI) to measure the water content distribution in a polymer electrolyte membrane under fuel cell operation with and without a supply of liquid water. The supply of liquid water to the membrane improved the cell performance by increasing the water content in the membrane and thus reducing the electrical resistance of the membrane. The study also showed that MRI is a promising method to investigate the distribution of water in the membrane of a fuel cell under operating conditions. 相似文献
137.
Numata M Koumoto K Mizu M Sakurai K Shinkai S 《Organic & biomolecular chemistry》2005,3(12):2255-2261
We already found that beta-1,3-glucan polysaccharides form polymeric complexes with certain polynucleotides, but the parallel vs. anti-parallel orientation in those complexes had remained unsolved. In this paper, this controversial problem has been discussed for curdlan/oligo(dA) complexes utilizing two different energy transfer techniques. The first system consists of a combination of fluorescein-labeled curdlan and 3'-(or 5'-)tetramethyl-rhodamine (TAMRA)-labeled oligo(dA). The second system utilizes gold nanoparticles: that is, two curdlan chains were linked by a disulfide bond and after complexation with oligo(dA), the complex was immobilized on gold nanoparticles. In this system, TAMRA was attached to the 3'(or 5') end of oligo(dA) and the gold particle acted as a fluorescence quencher (energy acceptor). These experiments have led us to conclude that in the curdlan/oligo(dA) complex, parallel orientation is more favourable than anti-parallel orientation. These findings have enabled us to envision a clearer image for the complexation mode between beta-1,3-glucan polysaccharides and polynucleotides. 相似文献
138.
Di(4-pyridyl)diazomethanes having two and four ortho chlorine groups were prepared, and the triplet carbenes generated from them were characterized by ESR and UV/vis at low temperature and time-resolved UV/vis at room temperature. An appreciable increase in the stability of triplet carbenes is achieved by introducing ortho chlorine groups. [structure: see text] 相似文献
139.
Sasaki K Sugou K Miyamoto K Hirai J Tsubouchi S Miyasaka H Itaya A Kuroda Y 《Organic & biomolecular chemistry》2004,2(19):2852-2860
The nonameric porphyrin assemblies constructed with the series of free base tetraphenylporphyrins Pn having four pyrazine moieties linked with alkyl chains of different lengths, (CH2)n (n = 1, 5, 9, 17, 30), and dimeric [meso-tetrakis(2-carboxy-4-nonylphenyl)porphyrinato]zinc(II), ZnP2, show the effective light-collection effect and the typical Forster-type energy transfer from ZnP2 to Pn. 相似文献
140.