An annular-shaped, high power nitrogen microwave induced plasma (N(2)-MIP) produced at atmospheric pressure by an Okamoto cavity, as a new excitation source for atomic emission spectrometry (AES), has been used for the simultaneous determination of bismuth and tellurium in steels with the hydride generation method. Under the optimized experimental conditions, the best attainable detection limits at the Bi I 195.389 nm and Te I 200.200 nm lines were 110 and 86 ng/ml for bismuth and tellurium, respectively. The linear dynamic ranges for bismuth and tellurium were 300 to 30,000 ng/ml. The presence of several diverse elements was found to cause a more or less depressing interference with the proposed technique. When bismuth and tellurium in steels were determined, a large amount of Fe(III) in the solution caused a severe depressing interference, while the presence of Fe(II) showed little or no significant interference. Of the several interference-releasing agents examined, l-ascorbic acid was found to be the most preferable to reduce Fe(III) to Fe(II) prior to hydride generation. The concentrations of bismuth and tellurium in steels were determined by the proposed technique. The results obtained by this method were in good agreement with their certified values.

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An annular-shaped high power nitrogen microwave induced plasma atomic emission spectrometry with a hydride generation method is described for the determination of lead in steel. Under the optimized experimental conditions, the best attainable detection limit at the Pb I 368.347 nm lines was 35.2 ng ml 1 for lead. The linear dynamic range for lead was 100 to 30000 ng ml 1 in concentrations. The presence of several diverse elements was found to cause a more or less depressing interference with the proposed technique. Of the several oxidizing agents examined, hydrogen peroxide for lead was found to be the most preferable to oxidize lead prior to hydride generation. When lead in two certified reference materials of steel was determined, a large amount of Fe(III) in the solution caused a severe depressing interference, while the presence of Fe(II) showed little or no significant interference. Of the several interference-releasing agents examined, L-ascorbic acid was found to be the most preferable to prereduce Fe(III) to Fe(II). The concentrations of lead in steel were determined by the use of the standard additions method. The results obtained by this method were in good agreement with their certified values.

This paper describes a novel adaptive-hierarchical-filtering technique to achieve high-quality magazine image reproduction on computer peripherals such as color copier, or scanner plus printer.Commercial magazine images are halfoned images. Unacceptable noises and moire distortion may result when halftone images are copied (i.e., scanned and printed). In this paper, we analyze moire patterns formation characterized by the following factors: Moire patterns formation depends on the following factors:(1) halftone screen frequency, how many lines per inch (i.e., lpi) (2) scan frequency, how many dot per inch, (dpi) (3) screen angle which is the screen orientation against the scan direction, (4) scanner aperture (i.e., scanner characteristics), (5) halftoning and printing mechanisms, (6) viewing conditions. Error diffusion tends to randomize the moire patterns, and cluster-dot or line screen show more moire distortion.We developed a set of variable-length low-pass filters that have a nice inheritance of canceling aliased low frequency components (moire distortion). High pass filtering is also applied to sharpen image edges. A hierarchical filter classifier was developed to determine that an edge is either a global true edge (for sharpening enhancement) or a local halftone's micro-structural edge (for LPF for moire reduction). Depending on the classifier, adaptive LPF is applied to achieve the smooth transition between sharp edges and smooth halftone regions. Thus, we achieves overall high-quality output images.Experimental results have been shown the effectiveness of the presented technique that works well on wide combinations of above-mentioned 6 factors for high-quality magazine image reproduction.