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Theoretical calculations have been performed for the ν9/2+[624](i13/2) and ν7/2-[503](f7/2) bands of 185Pt in the framework of particle-rotor model. The band properties of signature splitting and configuration mixing have been analyzed. The level energy and signature splitting before the band crossing can be well interpreted by introducing triaxiality. The positive-parity yrast band is pro posed to be dominated by the ν9/2+[624](i13/2) component, while the negative-parity band shows strong mixing of ν7/2-[5...  相似文献   
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A treatment of sites appropriate to fluid percolation in bond controlled processes results in sensitivity of breakup of the defender to the degree of size-correlation for three-dimensional networks. In strongly correlated lattices network control of invasion yields to a statistical treatment as a result of improved accessibility.  相似文献   
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A number of algorithms have been developed for the optimization of power plant maintenance schedules. However, the true test of such algorithms occurs when they are applied to real systems. In this paper, the application of an Ant Colony Optimization formulation to a hydropower system is presented. The formulation is found to be effective in handling various constraints commonly encountered in practice. Overall, the results obtained using the ACO formulation are better than those given by traditional methods using engineering judgment, which indicates the potential of ACO in solving realistic power plant maintenance scheduling problems.  相似文献   
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The first simultaneous quantification of neomycin and bacitracin using liquid chromatography evaporative light scattering detection as an alternative to MS detection and pre-/post-column derivatisation, respectively, was the aim of this study. The developed method was validated for two strength of neomycin and one strength of bacitracin in sterile pharmaceutical formulation and is a fast and efficient tool for content uniformity tests in quality control. With this method the separation of neomycin from sulfate and the base line separation of the four major components of bacitracin (bacitracin A, B1, B2 and B3) was achieved. These four components are responsible for 96% of the microbiological activity. A Phenomenex Synergi POLAR analytical column (250 mm × 4.6 mm, 4 μm I.D.) in combination with 0.5% perfluoropropionic acid and acetonitrile in gradient mode, the peaks of interest could be separated with high efficiency within 14 min. The calibration was performed using a second order regression with an R 2 = 0.9999 for neomycin (B and C) sulfate and R 2 = 0.9996 for bacitracin A, B1, B2 and B3. The results of the accuracy evaluation were 99.2 and 99.7%, respectively, for neomycin and 100.8% for bacitracin. Injection precision results are 0.4–1.5 RSD% recorded for six injections. The established method has a high potential for routine high-throughput analyses in the pharmaceutical industry.  相似文献   
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We have used fluorescence spectroscopy to study photoinduced biodegradation of ortho-cresol, para-cresol and mixture of them in water when excited by different UV radiation sources. We show that the efficiency of photolysis for both the individual isomers and the mixture of cresols is higher for excitation by radiation at λ ∼ 222 nm. Pre-irradiation of aqueous cresol solutions slows down subsequent biodegradation. Using a combination of UV irradiation and the strain Penicillium tardum H-2 for utilization of the cresol mixture led to complete degradation of para-cresol and partial degradation of ortho-cresol. Spectral and chromatographic study of the qualitative composition of the metabolites formed during biodegradation of para-cresol showed that preparatory metabolism of such compounds occurs both through oxidation of the methyl group with formation of 4-hydroxybenzoic acid and through hydroxylation with formation of 4-methylcatechol. __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 75, No. 2, pp. 250–255, March–April, 2008.  相似文献   
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