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91.
Bozena Stepnik-Swiatek Jan Malyszko 《Monatshefte für Chemie / Chemical Monthly》1982,113(6-7):715-718
The diffusion coefficients of Cu(I) ions in concentrated aqueous Ca(ClO4)2 solutions have been determined from the limiting currents of anodic oxidation at the rotating disc electrode.
Zur Bestimmung der Diffusionskoeffizienten von Cu(I)-Ionen in konzentrierten Perchloratlösungen (Kurze Mitteilung)
Zusammenfassung Diffusionskoeffizienten von Cu(I)-Ionen in konzentrierten wäßrigen Ca(ClO4)2-Lösungen wurden durch Messung der anodischen Grenzströme an der rotierenden Scheibenelektrode bestimmt.相似文献
92.
A. M. Zenkour 《Archive of Applied Mechanics (Ingenieur Archiv)》2006,76(1-2):89-102
This paper presents accurate elastic solutions for the rotating variable-thickness and/or uniform-thickness orthotropic circular cylinders. The present circular cylinder may contain a uniform-thickness solid core of rigid or homogeneously isotropic material. Different cases of rotating cylinders of various cores are investigated. These cylinders include completely isotropic solid cylinder, uniform-thickness orthotropic cylinder containing an isotropic core, variable-thickness orthotropic cylinder containing an isotropic core, uniform-thickness orthotropic cylinder containing a rigid core, and variable-thickness orthotropic cylinder containing a rigid core. For all cases studied, exact elastic solutions are obtained and numerical results are presented. The results include the radial, hoop, and axial stresses and radial displacement of the five cylinder configurations. The distributions of displacement and stresses through the radial direction of the rotating cylinder are obtained and comparisons between different cases are made at the same angular velocity. 相似文献
93.
Ahmet N. Eraslan 《European Journal of Mechanics - A/Solids》2003,22(6):274-874
Analytical solutions for the stress distribution in rotating parabolic solid disks are obtained. The analysis is based on Tresca's yield criterion, its associated flow rule and linear strain hardening. It is shown that, the deformation behavior of the convex parabolic disk is similar to that of the uniform thickness disk, but in the case of concave parabolic solid disk, it is different. In the latter, the plastic core consists of three different plastic regions with different mathematical forms of the yield criteria. Accordingly, three different stages of elastic–plastic deformation occur. All these stages of elastic–plastic deformation are studied in detail. It is also shown mathematically that in the limiting case the parabolic disk solution reduces to the solution of rotating uniform thickness solid disk. 相似文献
94.
95.
R. Meinel 《Annalen der Physik》2004,13(10):600-603
It is shown that the extreme Kerr black hole, i.e. the one with the maximal angular momentum for a given mass, is the only candidate for a black hole limit of rotating fluid bodies in equilibrium. 相似文献
96.
本文应用“相当弯矩法”对各种载荷作用下的变圆截面静定梁的变形(转角和挠度),用 BASIC 通用程序计算,得出小变形情况下的精确解,并绘制出大致的挠度曲线图.确定梁(轴)变形是工程中广泛存在的问题。建立通用程序既可快速、简便地解决工程实际问题,叉可以使“相当弯矩法”——优化的计算方法得到推广。 相似文献
97.
S. V. Korobtsev T. A. Kosinova Ya. R. Rakhimbabaev V. D. Rusanov 《Plasma Chemistry and Plasma Processing》1986,6(1):97-107
Investigations on separating hydrogen isotopes have been carried out in a system with plasma rotating in crossed E × B fields— a plasma centrifuge. The processing of chemical reactions in the plasma phase in a strong centrifugal field was simulated. High radial separation factors (up to 140) have been obtained for the decomposition of water vapor with simultaneous separation of hydrogen and oxygen. Because of spatial separation of the dissociation products there was no need for their special quenching. 相似文献
98.
99.
《Electroanalysis》2003,15(4):243-248
The electrochemical oxidation of dimethyl‐p‐phenylenediamine (DMPD) in aqueous solution (pH 7 phosphate buffer) has been studied under conventional hydrodynamic and microelectrode voltammetric conditions and found to undergo a two‐electron electrochemically reversible oxidation. Upon the application of ultrasound to the system an observed shoulder emerges in the oxidation wave. This effect has been attributed to the resolution of the two‐electron transfer processes occurring: the first a relatively fast electron transfer (0.1 cm s?1) followed by a second slower (10?3 cm s?1) electron transfer: under the very high mass transport rates induced by insonation an overpotential develops for the second electron transfer so leading to the observed voltammetric resolution. The range of mass transport conditions accessible via sonication allows the estimation of the two rate constants reported. 相似文献
100.
《Electroanalysis》2005,17(18):1616-1626
The rotation of redox‐functionalized magnetic particles (MPs) by means of an external magnet is a common practice for enhancing bioelectrocatalytic processes and for the amplification of biosensing events. The current densities generated by rotating redox‐functionalized MPs in two bioelectrocatalytic systems are compared to the current densities generated by rotating disc electrodes (RDE) functionalized with similar redox functionalities. The bioelectrocatalytic systems consist of pyrroloquinoline quinone (PQQ)‐functionalized MPs that oxidize NADH, and ferrocene‐functionalized MPs that mediate the bioelectrocatalyzed oxidation of glucose in the presence of glucose oxidase. The results reveal that only ca. 1% of the area of the redox‐functionalized MPs are electrically contacted with the electrode. Also, the current densities generated by the rotating MPs at high rotation speeds are lower than theoretically expected, presumably due to lose of electrical contact between the MPs and the electrode, and incoherent rotation of the particles on the electrode, due to insufficient magnetization. The comparison of the current densities in the bioelectrocatalytic systems in the presence of the rotating redox‐functionalized MPs to the analogous RDE systems allows us to elucidate the kinetics of electron transfer at the redox‐active MPs. 相似文献