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Ohne Zusammenfassung 相似文献
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An inspection of mechanically damaged areas on manufactured metal parts is necessary to produce high-quality products. A scanning probe on a sample is necessary for a conventional surface inspection system, which is time-consuming. We propose a novel high-speed detection method for defects on metal surfaces with rolling indentations. To obtain a large field of view in a measurement, we used a laser sheet that was expanded with a laser line generator and also used an expanded collimated beam, rather than a small laser spot as used in conventional techniques. Furthermore, we used an obliquely incident laser beam to suppress the effect of the rolling indentations surrounding defects, and also applied spatial frequency filtering to extract only defects. The spatial frequency filtering under oblique incidence is theoretically explained and defect extraction was investigated in experiments. 相似文献
286.
The synthesis of the biologically useful synthon 2-chloro-5-hydroxypyridine from 3-iodo-6-chloropyridine is described. 相似文献
287.
Rotation- and size-invariant object identification system using the liquid crystal on silicon device
We propose a shape discrimination technique using the optical matched spatial filter, which gives an identical result against randomly scattered objects of the same shape but different rotation and scale change. The main idea in this study is to apply optical coordinate transformation, which transforms rotation and scale change including a linear shift into translation, not to the objects themselves but to their Fourier spectra. Thus, rotation and scale change as well as the linear shift can be processed with the same optical matched spatial filter. In addition, we built a two-wavelength system for simultaneous processing of the optical matched spatial filter and optical coordinate transformation. In this system, both Fourier transform and the coordinate transformation were implemented merely by displaying computer-generated holograms (CGH) on the liquid crystal on silicon (LCOS) devices, resulting in a compact lensless system. 相似文献
288.
Zhang Q Liu Y Gao F Ding Q Cho C Hur W Jin Y Uno T Joazeiro CA Gray N 《Journal of the American Chemical Society》2006,128(7):2182-2183
The epidermal growth factor receptor (EGFR) tyrosine kinase was one of the first receptor tyrosine kinases to be targeted for drug development by the pharmaceutical industry due to its ubiquitous overexpression in a variety of tumors. Despite the validation of several quinazoline-based scaffolds in the clinic, there is a dearth of alternative chemical structure classes that are capable of inhibiting EGFR kinase activity selectively. Here we describe the discovery of potent and highly selective 4,6-disubstituted pyrimidine inhibitors of enzymatic and cellular EGFR activity and provide an explanation for their exceptional degree of kinase selectivity. 相似文献
289.
Toshiyuki Itoh Manabu Kanbara Shino Nakajima Yusuke Sakuta Shuichi Hayase Motoi Kawatsura Takashi Kato Kazutoshi Miyazawa Hidemitsu Uno 《Journal of fluorine chemistry》2009,130(12):1157-1163
The synthesis of a novel spiro type gem-difluorocyclopropane building block, 1,1,7,7-tetrafluoro-2,8-bis(hydroxymethyl)dispiro[2.2.2.2]decane (1), has been accomplished in optically pure form using chemo-enzymatic reaction protocol. Various types of diesters or dialkyl ether were prepared from diol (+)-1 or (−)-1 in optically active form and their helical twisting power (HTP) was evaluated by addition of 1.0 wt% to a non-chiral nematic liquid crystal host. Although their HTP values were not significant, all compounds showed liquid crystal property with SmC* phase when they were dissolved (20 wt%) in achiral nematic host liquid crystal. 相似文献
290.
Kaneda Y Peyghambarian N Miyazono K Shimatani H Honda Y Yoshimura M Mori Y Kitaoka Y Sasaki T 《Optics letters》2008,33(3):231-233
By delaying the second pass of the pump of a singly resonant optical parametric oscillator, the conversion efficiency can be improved. We show the experimental results of an intracavity-doubled singly resonant parametric oscillator pumped by a Q-switched laser. Using 0.49 mJ of pump energy at 532 nm from a diode-pumped Nd:YAG laser, 0.085 mJ of 488 nm was obtained with the optimum delay for the second pass of the pump, giving a conversion efficiency of 17%. The improvement over the case of a single-pass pump was 85%, and the improvement over the double-pass pump with a small delay was 40%. 相似文献