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Shan Zhao

Publications and source records attributed to Shan Zhao.

4 recordsLinked to original sources

Local spectral time-domain method for electromagnetic wave propagation.

We explore the feasibility of using a local spectral time-domain (LSTD) method to solve Maxwell's equations that arise in optical and electromagnetic applications. The discrete singular convolution (DSC) algorithm is implemented in the LSTD method for spatial derivatives. Fourier analysis of the dispersive error of the DSC algorithm indicates that its grid density requirement for accurate simulations can be as low as approximately two grid points per wavelength. The analysis is further confirmed by numerical experiments. Our study reveals that the LSTD method has the potential to yield high resolution for solving large-scale electromagnetic problems.

Journal Article↗

[Analysis of kojic acid in Aspergillus oryzae ferment by ion-pair reversed-phase high performance liquid chromatography].

A new and an efficient method for analyzing kojic acid in aspergillus oryzae ferment by ion-pair reversed-phase high performance liquid chromatography was developed. The kojic acid was well separated on a C18 column using methanol-0.01 mol/L disodium hydrogen phosphate and 2 mmol tetrabutylammonium bromide (4:96) as the mobile phase, followed by an UV detection at 226 nm. The detection limit was 0.012 microgram/ml. The spiked recoveries in wort-yeast culture, wort-peptone culture and potato-yeast-sugar culture were 98.2%, 103.4% and 97.2%, respectively. The RSD values were 0.51%, 0.45% and 0.43% respectively.

Aspergillus oryzae↗

Synchronization and information processing by an on-off coupling.

This paper proposes an on-off coupling process for chaos synchronization and information processing. An in depth analysis for the net effect of a conventional coupling is performed. The stability of the process is studied. We show that the proposed controlled coupling process can locally minimize the smoothness and the fidelity of dynamical data. A digital filter expression for the on-off coupling process is derived and a connection is made to the Hanning filter. The utility and robustness of the proposed approach is demonstrated by chaos synchronization in Duffing oscillators, the spatiotemporal synchronization of noisy nonlinear oscillators, the estimation of the trend of a time series, and restoration of the contaminated solution of the nonlinear Schrödinger equation.

Journal Article↗

[Rapid determination of metallothioneins in foods by capillary zone electrophoresis].

A rapid method for the analysis of metallothioneins (MT) in foods by capillary zone electrophoresis(CZE) was developed. Two isomers of MT (MT1, MT2) in foods were separated and determined. After a series of optimization, the separation and determination of MT1 and MT2 were obtained within 10 min by using the phosphate buffer system consisting of 0.02 mol/L Na2HPO4 and 0.02 mol/L NaH2PO4 (pH 7.0), and UV detection at 200 nm. Under the optimal experimental conditions, the minimum detectable limit was 1 mg/L, and the added standard recoveries of MT1, MT2 in foods were found to be in the range of 82.0%-93.4%. The relative standard deviations (RSD) were found to be lower than 10%. Therefore, with this simple and rapid method, the contents of two isomers in foods can be determined by external standard method after sample pretreatment.

Animals↗