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51.
Wavelength-scanning interferometers can separate the multiple interference signals generated by several reflecting surfaces
in the frequency space. Optical thickness variations of a three-layer object and its top surface shape were measured simultaneously
by a wavelength-scanning Fizeau interferometer. An efficient sampling window for the phase detection has been derived that
can compensate for the frequency detuning of the interference signal and suppress the cross talk from noise components in
other frequencies. From the experimental results, the refractive index variation of a glass plate was calculated with an accuracy
of ∼1 ppm, which is equivalent to several tens of nanometers in optical thickness variations.
The text was submitted by the authors in English. 相似文献
52.
Yoichiro Hoshina Satoru Ikegami Kyoko Fujimoto Akihiko Okuyama Tatsuhiro Harada Susan James Peter G. Griffiths Zemin Wu Michael Lilly Andrew M. Bray 《Tetrahedron letters》2005,46(52):9035-9038
2,3-Diphenylpropionic acid library for VLA-4 antagonist was synthesized on solid-phase. Comparison of the two synthetic routes via an orthogonal generation of two aromatic amino functional groups are discussed. From this work, several compounds were identified as potent VLA-4 antagonists. 相似文献
53.
Koji Nakano Toshihiro Kamada Kyoko Nozaki 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2006,118(43):7432-7435
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The synthesis of 1,4-dihydro-1-methoxy or ethyl -2-methyl-4-oxo-3-quinolineglyoxylic acid derivatives are described. α-Acetoxy-1,4-dihydro-1-hydroxy-2-methyl-4-oxo-3-quinolineacetic acid esters ( 7a, 7a ), which are key intermediates, were prepared by catalytic hydrogenation of 2-acetoxy-3-acetyl-4-hydroxy-4-(2-nitrophenyl) crotonic acid lactone ( 6 ) in methanol or ethanol. 相似文献
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Sadao Nakajima Kyoko Kosasa Yoshio Maruyama Seichi Kawai 《Spectrochimica Acta Part B: Atomic Spectroscopy》1982,37(8):685-690
The behavior of powdered samples in the region behind the incident and reflected shock wave were investigated. When the particle size is less than 8 μm, the powdered samples are effectively vaporized and excited to emit spectral lines. It was shown that the sample particles are scattered behind the incident wave and concentrated again in a narrow portion near the observation window by the use of a reflector so that intense emission can be attained. As an excitation source, the shock tube was used for the determination of trace metals contained in copper oxide. 相似文献