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Multiphoton Ionization Time-of-Flight Mass Spectrometry for the Detection of Bioactive Lignan
No full textMultiphoton ionization time-of-flight mass spectrometry (MPI-TOFMS) combined with a pulsed laser for sample vaporization was developed for the detection of a low-volatile compound in a solution. A solution containing Taiwanin A ((3E,4E)-3,4-bis(1,3-benzodioxol-5-ylmethylene)dihydro-2(3H)-furanone), which is a lignan that has an anticancer effect, was employed in the present study. Consequently, Taiwanin A could be detected by irradiating a laser pulse for vaporization to an inlet nozzle, rather than by heating. Therefore, the present method could be effective for detecting compounds with lower volatilities in a liquid sample
Phase Noise of Multiphase CMOS LC Oscillators Coupled by Mutual Inductors
No full textThere have beem many studies on the analysis and design of low-noise oscillators. Recently, much attention has been paid to the noise reduction technique using coupled oscillators. When oscillators are coupled, the coupling method is very important and affects various factors, for example, the level of noise. In this study, we analyze the phase noise of multiphase CMOS LC oscillators coupled by mutual inductors by using the impulse sensitivity function. From the simulation results, using mutual inductors as coupling elements can reduce the phase noise. Also, for oscillators coupled by mutual inductors, we show that setting a coupling coefficient of around 0.2 can realize the lowest phase noise near the oscillation frequency
