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31.
In a digital toll switching office a digital multifrequency (MF) receiver may be more economical than the present analog MF receiver. This paper suggests an algorithm that could be used for digital implementation of such a receiver. The algorithm employs discrete Fourier transform and leads to more efficient design than a system using second-order digital bandpass filters. The presented results of computer simulation of the digital MF receiver employing this method indicate satisfactory performance and good immunity to random noise interference. 相似文献
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Summary The synthesis of the lactone of dihydrosenecic acid was described. 相似文献
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Trimethylsiloxyl radicals add to dialkyl sulphides to produce sulphuranyl radicals, whilst triethylsilyl radicals bring about homolyric dealkylation of dialkyl sulphides. 相似文献
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Carlos Segura Carlos A. Coello Coello Gara Miranda Coromoto León 《4OR: A Quarterly Journal of Operations Research》2013,11(3):201-228
In recent decades, several multi-objective evolutionary algorithms have been successfully applied to a wide variety of multi-objective optimization problems. Along the way, several new concepts, paradigms and methods have emerged. Additionally, some authors have claimed that the application of multi-objective approaches might be useful even in single-objective optimization. Thus, several guidelines for solving single-objective optimization problems using multi-objective methods have been proposed. This paper offers a survey of the main methods that allow the use of multi-objective schemes for single-objective optimization. In addition, several open topics and some possible paths of future work in this area are identified. 相似文献
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Faddeev N. A. Kuriganova A. B. Leont′ev I. N. Smirnova N. V. 《Russian Journal of Electrochemistry》2019,55(4):346-350
Russian Journal of Electrochemistry - The Pt/C, Rh/C, and Pt-Rh/C catalytic systems with uniform distribution of metal phase over the surface of carbon support and an average size of Pt and Rh... 相似文献
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Theoretical and experimental investigation on the oxidation of gallic acid by sulfate radical anions
Caregnato P Gara PM Bosio GN Gonzalez MC Russo N Michelini Mdel C Martire DO 《The journal of physical chemistry. A》2008,112(6):1188-1194
By monitoring the decay of SO4*- after flash photolysis of aqueous solutions of S2O82- at different pH values, the kinetics of the reaction of SO4*- radicals with gallic acid and the gallate ion was investigated. The bimolecular rate constants for the reactions of the sulfate radicals with gallic acid and the gallate ion were found to be (6.3 +/- 0.7) x 10(8) and (2.9 +/- 0.2) x 10(9) M(-1) s(-1), respectively. On the basis of the oxygen-independent second-order decay kinetics and on their absorption spectra, the organic radicals formed as intermediates of these reactions were assigned to the corresponding phenoxyl radicals. DFT calculations in the gas phase and aqueous solution support formation of the phenoxyl radicals by H abstraction from the phenols to the sulfate radical anion. The observed recombination of the phenoxyl radicals of gallic acid to yield substituted biphenyls and quinones is also supported by the calculations. HPLC/MS product analysis showed formation of one of the predicted quinones. 相似文献
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大气CO2是一种温室气体,在气候变化等领域起着关键作用。基于NDIR技术研制了可用于探测大气CO2垂直廓线的无线传感系统。系统采用电调制型的红外辐射光源、双通道探测器并结合超低功耗单片机实现大气CO2信号的采集与控制。提出采用调制信号周期内扣除信号起伏与背景噪声的方法,使得本系统具有0.29%的相对测量误差。通过分时工作的方式解决了数字式无线电探空仪中高频发射机对CO2检测电路运算放大器的电磁辐射干扰,进而实现了气象探空仪与小型化的CO2探测系统的高度集成。通过与地面LI-COR LI7500对比分析,两者表现出较好的一致性,24 h测量数据的相关性达0.89,表明所研制的探测系统的稳定性与准确性。为实现大气CO2垂直廓线的探测提供一种选择。 相似文献