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321.
The investigation of the combination of enzymatic and chemical synthetic processes for the production of useful compounds
has been carried out. This review focuses on the enzymatic transformation of chemically synthesized 3-chloroalanine into useful
amino acids. 相似文献
322.
We consider Green polynomials at roots of unity, corresponding to partitions which we call l-partitions. We obtain a combinatorial formula for Green polynomials corresponding to l-partitions at primitive lth roots of unity. The formula is rephrased in terms of representation theory of the symmetric group. 相似文献
323.
324.
Kazuhiko Miyazaki Hirohumi Kasada Yusuke Nishigaki Hideaki Yoshioka Shingo Nihonmori 《International Journal of Infrared and Millimeter Waves》1994,15(10):1663-1668
By replacing the conventional (non line-selective) unstable resonator, we succeeded in developing the very high power line-selective (line-tunable) CO2 laser as a pumping source for high power molecular gas (e.g.NH3) lasers in the infrared and far-infrared regions.The experiments were performed by using the very high power CO2 laser (4A unit of Lekko VIII) at The Institute of Laser Engineering, Osaka University.The output power of 9R(30)9.22µ m line from the developed CO2 laser, for instance, exceeded 0.5GW/pulse (50J/pulse with pulse width of 100nsec). 相似文献
325.
326.
Hidetaka Arimura Takaharu Ikeda Takeshi Ikari Hideaki Kubota Masao Matsumoto Atsushi Takigawa Nobuyuki Nakamori Hitoshi Kanamori 《Optical Review》1995,2(2):154-158
A low-speed screen/film system was used to investigate structure mottle, i.e., the density fluctuation of an x-ray film due to inhomogeneous screen structure. The tube voltage dependence of the Wiener spectra of the structure mottle was separately determined for front and back film emulsions. The Wiener spectral values of the structure mottle of the front emulsion were greater than those of the back emulsion at lower tube voltages. The spectral values of the structure mottle of the front emulsion decreased with tube voltage, while those of the back emulsion increased. We explain these phenomena by the behavior of the Wiener spectra of the relative spatial fluctuation of fluorescence intensity due to following reasons: (1) spatial thickness fluctuation of the screen produces a relative spatial fluctuation of x-ray energy absorbed in the screen, and (2) as the distance between the emulsion of the film and the average position of the x-ray absorption in the screen lengthens, the number of random scattering and absorption of light photons increase.Presented at the International Commission for Optics Topical Meeting, Kyoto, 1994. 相似文献
327.
M Hori T Iwamura T Morita E Imai H Oji T Kataoka H Shimizu M Ban M Nozaki M Niwa 《Chemical & pharmaceutical bulletin》1989,37(8):2222-2224
Synthesis of 3-cyclopropylmethyl-, 3-cyclobutylmethyl-, and 3-methyl-8-benzoylthio-2,6-methano-3-benzazocines (1j-l) was performed by regio-selective chlorosulfonation of non-narcotic 8-deoxy derivatives (1a-c) followed by reduction and benzoylation. 3-Benzoylthiomorphinans (2h-j) were also obtained by the same method. Compounds having small-ring substituents (1k, 1l, 2i, 2j) were found to be weak but pure mu- and delta-opioid antagonists. The analgetic activity of 1k was almost equal to that of pentazocine. 相似文献
328.
Most lenses composed of spherical or aspherical surfaces have symmetrical focusing properties about an optical axis. On the other hand, unconventional optical systems such as cylindrical lenses, astigmatic or progressive power glasses have axially asymmetrical focusing properties. In this study, the method of measuring focusing properties by the moire technique is extended to asymmetrical lenses. Some unconventional lenses were experimentally tested, and the focusing power in the interesting region and azimuthal direction of the aperture was evaluated. 相似文献
329.
M Hori T Iwamura E Imai H Shimizu T Kataoka M Nozaki M Niwa H Fujimura 《Chemical & pharmaceutical bulletin》1989,37(5):1245-1248
3-Acylthiomorphinans, 3-carbamoylthio-3-deoxydihydromorphine and 3-benzoylthio-9-aza-17-carbamorphinan were synthesized by Newman-Kwart rearrangement of the corresponding O-thiocarbamates. The analgetic activities were lower than that of pentazocine, and the opioid receptor binding affinities were very weak. These acylthiomorphinans showed low antinociceptive activity compared with corresponding sulfur-containing benzomorphans. 3-Carbamoylthio-deoxydihydromorphine had no significant analgetic activity. 相似文献
330.
The modulated point vortex model associated with the Hasegawa-Mima equation is used to study the dynamical behavior of drift wave vortices in a bounded region. When a circle is taken as the boundary of the region, the potential for the vortices can be constructed with the aid of the circle theorem which replaces the boundary by the mirror images of the vortices inside the circle and ensures that the potential for the vortices is zero on the boundary. Periodic, aperiodic and chaotic motions are realized depending on the number of vortices and the magnitude of the value of the diamagnetic drift which breaks the rotational symmetry and has a tendency to drive vortices into chaotic motion. 相似文献