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131.
A method for the microdetermination of periodate in the presence of iodate is presented. It is based on reduction of periodate to iodate by leucothionine generated in situ by photochemical reaction between EDTA and blue thionine. Biamperometric curves are used for evaluation, representing reduction time for the periodate versus the current generated in the oxidation of the Tred in excess after the end-point. A polarographic study of the process is presented. An applied potential of 100 mV is suitable for the biamperometric measurements with Pt—Pt electrodes. The method is applicable for 0.4–45 ppm periodate. Iodate does not interfere up to IO-3 : IO-4 ratios of 100:1. 相似文献
132.
Amperometric oxygen electrodes are useful transducers for enzymatic analyses. One must, however, account for contributions from oxygen incorporation or depletion caused by sample introduction, stirring and diffusion, or non-enzymatic reactions, as well as for instrumental response time. Examples of various characteristics of these contributions are shown and discussed from a theoretical basis. 相似文献
133.
EXISTENCEOFFORECASTANDDECISIONHORIZONSFOROPTIMALCONTROLPROBLEMSOFNONLINEARSYSTEMS¥ZhangChengyun(张成云)(FudanUniversity,复旦大学,邮编:... 相似文献
134.
The nonsymmetric Lanczos method has recently received significant attention as a model reduction technique for large-scale systems. Unfortunately, the Lanczos method may produce an unstable partial realization for a given, stable system. To remedy this situation, unexpensive implicit restarts are developed which can be employed to stabilize the Lanczos generated model.This work was supported in part by ARPA (US Army ORA4466.01), by ARPA (Grant 60NANB2D1272), by the Department of Energy (Contract DE-FG0f-91ER25103) and by the National Science Foundation (Grants CCR-9209349 and CCR-9120008). 相似文献
135.
136.
Molecular quantum beats are shown for the case of biacetyl, to vary strongly under the influence of weak magnetic fields. Values for dephasing constants for a gas-phase molecular system were determined. Information on sub-Doppler level splittings in the intersystem-crossing process is obtained. 相似文献
137.
X.H. Tang 《Journal of Mathematical Analysis and Applications》2005,301(2):313-335
In this paper, sufficient conditions are established for the asymptotical behavior of solutions of the delay differential equation
x′(t)=F(t,xt)+G(t,xt) 相似文献
138.
P.H. Kobrin U. Becker C.M. Truesdale D.W. Lindle H.G. Kerkhoff D.A. Shirley 《Journal of Electron Spectroscopy and Related Phenomena》1984,34(2):129-139
The partial cross-sections and photoelectron angular distributions for several lines in atomic Mn have been measured at photon energies between 50 and 72eV. The intensities of the 3d correlation satellites at 24–26 eV binding energy behave similarly to the mainline intensity near the 3p → 3d giant resonance, but show an enhancement near the 3p threshold which is not present for the main line. A configuration-interaction analysis is applied to help identify the origins of the satellites. The 3p/3d branching ratio from 55–72eV and the shape of the 3d cross section in the resonance region are in good agreement with many-body perturbation-theory calculations. 相似文献
139.
Brian D. O. Anderson 《Journal of statistical physics》1969,1(1):133-147
The paper considers the problem of passing from a stationary covariance, or spectral matrix, associated with the output of a constant linear finite-dimensional system excited by white noise to the set of all possible systems of minimum possible dimension which will generate this covariance. The problem, originally posed by R. E. Kalman in 1965, is solved by identifying each possible system with the solution of a quadratic matrix inequality; an algorithm for the solution of the inequality is also presented.Work supported by the Australian Research Grants Committee. University of New castle Technical Report EE-6816. 相似文献
140.
窄禁带光子晶体能态密度的研究 总被引:3,自引:3,他引:0
利用平面波展开法研究了窄禁带光子晶体材料的能态密度分布情况,得到了窄禁带材料构成的三角晶格光子晶体能态密度随着介电常数差值的增大而增大,并且分析了氮化镓在f=0.3时,能态密度分布最小,出现最大光子带隙。研究结果为窄禁带光子晶体器件的构造提供理论依据。 相似文献