A method for detecting sudden-up and sudden-down of voltage includes generating reference sine signal with the same phase and fixed amplitude as voltage signal of power supply, rectifying power supply voltage signal and reference sine signal then comparing rectified power supply voltage signal with .....
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An electric field instrument comprises a detection device, a signal processing device and a data analysis device. The detection device sends electric field signals to the signal processing device; a movable sheet, a drive device thereof, two groups of fixed sheets and a sensor are arranged in the de.....
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The present invention can be obtained in a relatively mild conditions to high speed, high selective catalytic carbonylation of methanol to acetic acid, methyl acetate, acetic anhydride carbonylation catalyst. Method is to design the molecular structure of the catalyst, methanol carbonylation reactio.....
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Mode photonic crystal fiber comprises a core of a substantially transparent material having a core. Said core material having a core refractive index and length, and having a core diameter. Surrounding said optical fiber further comprises a core material at the outer cladding region. The cladding re.....
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The present invention relates to a two-way shape memory effect of a polymer composite material and its preparation, characterized in that the polymer composite material having shape memory polymeric material and active response to sticky and elastic material made of superposition; Polymer composite .....
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