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131.
The kinetics of the Ru(III)-(edta) (edta(4-) = ethylenediaminetetraacetate) catalyzed oxidation of l-arginine by H(2)O(2) mimicking the action of nitric oxide synthases (NOSs) has been studied spectrophotometrically. The time course of the reaction of [Ru(V)(edta)O](-) with l-arginine was followed at 390 nm under catalytic turn-over conditions. Formation of NO in the reacting system has been confirmed with an isolated nitric oxide free radical analyzer. A detailed reaction mechanism in agreement with the spectral and kinetic data is presented. 相似文献
132.
Horner-Wadsworth-Emmons (HWE) or Still-Gennari olefination of TBS-protected 3,3-difluoro-4-hydroxy-2-ones, derived from the difluoroallylboration of aldehydes, provides the Z-isomer of 4,4,-difluoropent-2-enoates. These, upon hydrolysis, followed by Yamaguchi cyclization, afford 5,5-difluoro-4-methyl-5,6-dihydro-α-pyrones in high yields. 相似文献
133.
We address stability of a class of Markovian discrete-time stochastic hybrid systems. This class of systems is characterized
by the state-space of the system being partitioned into a safe or target set and its exterior, and the dynamics of the system
being different in each domain. We give conditions for L
1-boundedness of Lyapunov functions based on certain negative drift conditions outside the target set, together with some more
minor assumptions. We then apply our results to a wide class of randomly switched systems (or iterated function systems),
for which we give conditions for global asymptotic stability almost surely and in L
1. The systems need not be time-homogeneous, and our results apply to certain systems for which functional-analytic or martingale-based
estimates are difficult or impossible to get. 相似文献
134.
135.
136.
We consider three dimensional finite element computations of thermoelastic damping ratios of arbitrary bodies using Zener’s
approach. In our small-damping formulation, unlike existing fully coupled formulations, the calculation is split into three
smaller parts. Of these, the first sub-calculation involves routine undamped modal analysis using ANSYS. The second sub-calculation
takes the mode shape, and solves on the same mesh a periodic heat conduction problem. Finally, the damping coefficient is
a volume integral, evaluated elementwise. In the only other decoupled three dimensional computation of thermoelastic damping
reported in the literature, the heat conduction problem is solved much less efficiently, using a modal expansion. We provide
numerical examples using some beam-like geometries, for which Zener’s and similar formulas are valid. Among these we examine
tapered beams, including the limiting case of a sharp tip. The latter’s higher-mode damping ratios dramatically exceed those
of a comparable uniform beam. 相似文献
137.
Nonlinear Dynamics - We consider the theoretical maximum extractable average power from an energy harvesting device attached to a vibrating table which provides a unidirectional displacement... 相似文献
138.
A. Chatterjee B. K. Chakrabarti 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,54(3):399-404
We study here numerically the behavior of an ideal gas like model of markets having
only one non-consumable commodity. We investigate the behavior of the
steady-state distributions of money, commodity and total wealth,
as the dynamics of trading or exchange of money and commodity proceeds,
with local (in time) fluctuations in the price of the commodity.
These distributions are studied in markets with agents having uniform and
random saving factors. The self-organizing features in money distribution
are similar to the cases without any commodity (or with consumable
commodities), while the commodity distribution shows an exponential decay.
The wealth distribution shows interesting behavior: gamma like
distribution for uniform saving propensity and has the same power-law tail,
as that of the money distribution, for
a market with agents having random saving propensity. 相似文献
139.
S Kailas A Navin A Chatterjee P Singh A Saxena D M Nadkarni D C Biswas R K Choudhury S S Kapoor 《Pramana》1993,41(4):339-344
The measurements of fission fragment angular distributions for the system19F+232Th have been extended to the sub-barrier energies of 89.3, 91.5 and 93.6 MeV. The measured anisotropies, within errors are
nearly the same over this energy region. However, the deviation of the experimental values of anisotropies from that of standard
statistical model predictions increases as the bombarding energy is lowered. 相似文献
140.
J. M. Chatterjee M. Sarkar S. Roy K. Weidenbrü 《Radiation Physics and Chemistry》2002,64(5-6):369-372
Samples of the raw input material and industrial wastes collected at different processing stages of lead smelting units have been analyzed using the synchrotron induced X-ray fluorescence method to detect and estimate the presence of heavy metals. Heavy metals such as Sb, Cd, Sn, Pb are found to be present in significant amounts. 相似文献