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81.
We present a fitting method for obtaining a functional form of the refractive index profile of planar microlenses made by ion exchange techniques from total shearing interferometric measurements. Compared to the usual power series expansion fit, this method allows a reduction in the number of coefficients needed to characterize a lens. 相似文献
82.
Naohiro Murayama Takao Oikawa Takayuki Katto Ken'ichi Nakamura 《Journal of Polymer Science.Polymer Physics》1975,13(5):1033-1047
The piezoelectricity of PVDF thermoelect rets formed with vacuum-coated aluminum electrodes has been investigated in detail. The piezoelectricity depends on the β-form crystal structure of PVDF homopolymer and copolymers. However, the piezoelectricity is not attributed to the stress dependence of the spontaneous polarization of β-form crystals, but rather to the persistent polarization arising from trapped charges. The trapping mechanism is discussed. 相似文献
83.
Hidetoshi Iwamoto Takaaki Sonoda Hiroshi Kobayashi 《Journal of fluorine chemistry》1984,26(4):535-537
Anion-catalyzed phase-transfer catalysis was successfully applied to diazotization of pentafluoroaniline in a dichloromethane-aqueous sulfuric acid two-phase system. The resulting diazonium group was coupled with anisole, 1-methoxynaphthalene, and mesitylene, and replaced with bromo, hydryl, and phenyl substituents under a two-phase condition. 相似文献
84.
Kikuo Oikawa 《应用有机金属化学》1988,2(4):391-393
This paper reviews the use of arsenic compounds in semiconductor manufacture and emphasizes the role of alkylated arsenic compounds. 相似文献
85.
Yuji Oikawa Tatsuyoshi Tanaka Kiyoshi Horita Tadao Yoshioka Osamu Yonemitsu 《Tetrahedron letters》1984,25(47):5393-5396
The DMPM (3,4-dimethoxybenzyl) protection for hydroxy function was deprotected more readily than the MPM (p-methoxybenzyl) protection by DDQ oxidation under neutral conditions, and applied to the synthesis of some synthons to macrolide and polyether antibiotics. 相似文献
86.
87.
Kazuaki Fukamichi Hidetoshi Hiroyoshi Michio Kikuchi Tsuyoshi Masumoto 《Journal of magnetism and magnetic materials》1979,10(2-3):294-299
The thermal expansion and magnetic properties of Fe-B and Fe-P amorphous alloys prepared from melts have been investigated. These amorphous alloys show distinct Invar characteristics. heir magnetic properties are also very similar to those of Fe-Ni crystalline Invar alloys; that is, the high-field susceptability and forced-volume magnetostriction are remarkably large, the magnetic moment per Fe atom does not increase linearly, the Curie temperature decreases with a decrease in concentration of B or P, and their reduced their magnetization curves are much flatter than those of crystalline pure Fe. 相似文献
88.
Onoda M Tokuyama H Uchiyama S Mawatari K Santa T Kaneko K Imai K Nakagomi K 《Chemical communications (Cambridge, England)》2005,(14):1848-1850
Strong fluorescence signals were observed after the reaction of novel reagents with hydroperoxides. 相似文献
89.
Let
be a very ample vector bundle of rank two on a smooth complex projective threefold X. An inequality about the third Segre class of
is provided when
is nef but not big, and when a suitable positive multiple of
defines a morphism X → B with connected fibers onto a smooth projective curve B, where KX is the canonical bundle of X. As an application, the case where the genus of B is positive and
has a global section whose zero locus is a smooth hyperelliptic curve of genus ≧ 2 is investigated, and our previous result
is improved for threefolds.
Received: 27 January 2005; revised: 26 March 2005 相似文献
90.
Intrinsic mechanism of pair breaking is given for dirty superconducting films. Dynamical interaction between electrons such as Coulomb interaction plays an essential role. The diffusion processes of both density- and pair-fluctuations are also important. The problem of the Thompson's parameter for the Maki term of fluctuation conductivity is solved and the correct dependence of the parameter of the sheet resistance Rsq is given. 相似文献