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Parallel current mode control algorithm for DC-DC converters is introduced in this paper. This control strategy is composed of two parallel terms: voltage term and current term which is calculated based on the input voltage, inductor current and output voltage. The new duty cycle algorithm requires only one multiplication, one division and three additions(More)
Eight compounds were isolated from the ethyl-acetate extract of the stem of Mallotus apelta Muell. -Arg. The structures of eight compounds were identified by means of spectroscopic analysis as 12-ursen-3-one (I), 3-hydroxy-12-ursen (II), mussaenoside (III), 6-methoxy-2H-1-benzopyron4-one (IV), ursolic acid (V), acetyl aleuritolic acid (VI),(More)
A technique of high-performance gel permeation chromatography (HPGPC)-evaporative light-scattering detection and circular dichroism (CD) was developed for the measurement of thermal effects on the homogeneity and conformation of polymeric carbohydrate conjugates and was applied to an acid polysaccharide conjugate (GTa) isolated from the composite enzyme(More)
Seven quantitative analysis models for Dafo Longjing tea, including tea color, liquor color, aroma, taste, infused leaf, total points of five factors and total points of six factors, were built by applying near infrared spectroscopy combined with partial least squares (NIRS-PLS), in order to find a objective and scientific method for tea quality evaluation.(More)
This paper proposes a simple circuit configuration for driving piezoelectric bimorph actuators in a high efficient way but not depolarizing the piezoceramics. Different from generating the bias voltages via some direct voltage converters, here two bias voltages are obtained from the driving voltage itself directly through a simple circuit. The values of the(More)
The quality and safety of Panax notoginseng products has become a focus of concern in recent years. Contamination with heavy metals is one of the important factors as to P. notoginseng safety. Cleaning treatments can remove dust, soil, impurities or even heavy metals and pesticide residues on agricultural products. But effects of cleaning treatments on the(More)
Panax notoginseng medicinal liquor (PML) has a long history of use in the function of blood circulation. However, the processing of PML is currently dependent on experience, which results in low efficiency and unstable quality of PML. A variety of substances of P. notoginseng have a strong ability to scavenge free radicals and antioxidant activity, but the(More)
Crude tea polysaccharides (CTPS) were extracted from low-grade green tea, separately named CTPS-I by water-boiling extraction method and CTPS-II by compound enzyme method, and CTPS-III extracted from tea leaves by compound enzyme method. The content of saccharide and protein of them were determined. The homogeneity distribution and mass ratio of(More)
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