Theoretical and experimental guideline of optimum design of defect-inspection apparatus for transparent material using phase-shift illumination approach

Optical Review - Machine vision system has great significance for the automatic inspection to enhance unclear defects. For the purpose of the improvement of the recognition accuracy in the...     

Synthesis of alkyl 2-phenylnicotinates

Various alkyl 6-ethoxy-2-phenyl-5,6-dihydro-4H-pyran-3-carboxylate 2A are easily converted to the corresponding nicotinates 3 by reaction with hydroxylamine hydrochloride in refluxing absolute ethanol.     

Determination of Sub-ppb Cadmium in Urine by Solid-Phase Extraction and Inductively Coupled Plasma-Mass Spectrometry

In order to determine low levels of Cd in urine samples, we tried to remove Mo interference using ICP-MS with a dynamic reaction-cell technique, but failed due to the low sensitivity and the variance with the standards. We then performed solid-phase extraction (SPE) before the ICP-MS measurement. A commercially available chelating resin, NOBIAS PA-1, was used for SPE, and could effectively remove Mo from urine samples, permitting the accurate determination of Cd by ICP-MS. This SPE-ICP-MS method gave 0.012 microg Cd L(-1) as the method limit of quantification, and the mean recovery of Cd spiked with 0.0505 and 5.05 microg L(-1) was 93.1 and 97.6%, respectively.     

Dynamic properties of second-harmonic intensity of a nanosecond-order laser pulse

Numerical and experimental results on the dynamic properties of the second-harmonic generation of Q-switched nanosecond-order laser pulses are described by reexamining the influence of the imperfect phase-matching condition. For a type-I noncritical phase-matching scheme, the fluctuation in the second-harmonic intensity owing to the change in environmental temperature can be effectively avoided by using the conversion region in the second-harmonic generation. In addition, the instability of the second-harmonic intensity owing to the variation in the fundamental intensity might be suppressed by introducing an optimized phase-mismatching condition to the reconversion region if the fundamental laser pulse has a flat-top profile. These approaches are expected to be applied for the peak-intensity stabilization of the pump laser used in optical parametric chirped pulse amplification.