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101.
Itsuo Mori Yoshikazu Fujita Minako Toyoda Yoko Takeuchi 《Fresenius' Journal of Analytical Chemistry》1992,344(6):292-294
Summary A highly sensitive determination of osmium(VIII) is based on the decolouring reaction with pyrogallolphthalein (gallein) and hydrogen peroxide in the presence of Brij 35. Beer's law was obeyed in the range of 0–0.5 ng of osmium(VIII) per 10 ml and the apparent decomposed absorption coefficient was 2.5×109 l mol–1 cm–1 at 535 nm.Application of xanthene derivatives in analytical chemistry. Part XCIII. Part XCII see ref. [1] 相似文献
102.
Nobuko Takeuchi 《Journal of Geometry》1989,34(1-2):195-200
A sphereM inE
3 is characterized as a simply connected complete smooth surface which contains a circle through each pointp M contained in a normal plane ofM atp.The author would like to thank Professor K. Ogiue for his valuable suggestions. 相似文献
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In this paper we propose a numerical reconstruction method for solving a backward heat conduction problem. Based on the idea of reproducing kernel approximation, we reconstruct the unknown initial heat distribution from a finite set of scattered measurement of transient temperature at a fixed final time. Standard Tikhonov regularization technique using the norm of reproducing kernel is adopt to provide a stable solution when the measurement data contain noises. Numerical results indicate that the proposed method is stable, efficient, and accurate. 相似文献
105.
In this paper, we investigate a delayed HIV infection model that considers the homeostatic proliferation of CD4+ T cells. The existence and stability of uninfected equilibrium and infected equilibria(smaller and larger ones) are studied by analyzing the characteristic equation of the system. The intracellular delay does not affect the stability of uninfected equilibrium, but it can change the stability of larger positive equilibrium and Hopf bifurcation appears inducing stable limit c... 相似文献
106.
T. Takeuchi S. Uehara T. Hayashi 《Journal of Radioanalytical and Nuclear Chemistry》1980,56(1-2):25-35
Several dead time correction methods were compared experimentally with the exact correction method and their limits were discussed.
These correction methods were applied to neutron activation analysis of a biological sample. A special electronic circuit
and an additional counting equipment were used to obtain the fractional dead time with a suficiently high frequency. 相似文献
107.
Emission spectroscopy is applied for characterization of reactions occurring in air—acetylene flames normally used for atomic absorption spectrometry. Inter-element effects on the emissions of chromium and iron are discussed. Two atomic emission lines with different upper energies and a molecular emission line of the diatomic oxide MO are compared for determination of the excitation temperature and the degree of atomization in fuel-rich and lean flames. The reductive power of the fuel-rich flame is essential for atomization of chromium salts. Inter-element effects by iron can be attributed to the formation of refractory oxides, and to mutual catalytic oxidation. 相似文献
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