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201.
We make use of hypotrochoid curves to propose mixing devices with simple mechanism, which gives pseudo-Anosov mixings. We exhibit some experiments to see the efficiency of the device. 相似文献
202.
Takashi Kaneko Hiroo Katagiri Yasuhiro Umeda Takeshi Namikoshi Edy Marwanta Masahiro Teraguchi Toshiki Aoki 《Polyhedron》2009,28(9-10):1927-1929
We synthesized optically active polyradicals possessing an excess of one-handed helical backbone by helix-sense-selective polymerization (HSSP) of achiral monomers which was promoted by rhodium complex catalyst in the presence of (R)- or (S)-1-phenylethylamine. The monomer, which had two hydroxy groups and a hydrogalvinoxyl unit, gave the corresponding polymer with an optically active helical conformation stabilized by intramolecular hydrogen bonding. The chemical oxidation of the polymer yielded the corresponding optically active helical polyradical with high spin concentration. The static magnetic susceptibility of the chiral polyradical was measured using a SQUID magnetometer. We have found that the stronger antiferromagnetic interaction was observed for the polyradical synthesized by HSSP in comparison with the polyradical via polymerization in the presence of racemic phenylethylamine. 相似文献
203.
Asymptotic behaviors of zero modes of the massless Dirac operator H = α · D + Q(x) are discussed, where α = (α1, α2, α3) is the triple of 4 × 4 Dirac matrices, , and Q(x) = (q
jk
(x)) is a 4 × 4 Hermitian matrix-valued function with | q
jk
(x) | ≤ C 〈x〉−ρ, ρ > 1. We shall show that for every zero mode f, the asymptotic limit of |x|2
f (x) as |x| → + ∞ exists. The limit is expressed in terms of the Dirac matrices and an integral of Q(x) f (x).
相似文献
204.
Existence of Mach cone and helical vortical structure in the helical oscillation mode of an underexpanded circular jet was confirmed by using schlieren instantaneous photographs and drawing of the envelopes of the Mach cones by the superposition of spherical sound waves radiated from two moving sound sources about the jet axis at a supersonic speed. Existence of such structures was conjectured in our earlier paper [Umeda and Ishii, J. Acoust. Soc. Am. 110, 1845-1858 (2001)]. The envelopes of a Mach cone are observed as a V-shaped pattern composed of a pair of clear fine lines starting from a prominent point, which rotates about the jet axis. The helical vortical structure is observed as a bright pattern of the gathering of the tiny specks around the jet. It always appears to overlap on the envelopes of the moving Mach cones. 相似文献
205.
206.
Continuous monitoring of unbound flomoxef levels in rat blood using microdialysis and its new pharmacokinetic analysis 总被引:1,自引:0,他引:1
Microdialysis sampling method coupled to high-performance liquid chromatography with UV detection was applied to continuous monitoring of in vivo unbound flomoxef concentration in rat blood. By comparison with ultrafiltration method, it was demonstrated that it gave reliable results for the unbound drug monitoring in blood. Furthermore, a new method was presented for the calculation of pharmacokinetic parameters from the data obtained by the microdialysis method. 相似文献
207.
Hasegawa T Fujisawa T Numata M Matsumoto T Umeda M Karinaga R Mizu M Koumoto K Kimura T Okumura S Sakurai K Shinkai S 《Organic & biomolecular chemistry》2004,2(21):3091-3098
Schizophyllans carrying beta-lactoside and alpha-mannoside appendages were prepared from native schizophyllan through NaIO4 oxidation followed by reductive amination using aminoethyl-beta-lactoside and alpha-mannoside, respectively. The resulting schizophyllans form stable macromolecular complexes with polynucleotides, such as poly(C) and poly(dA). Specific affinity between these macromolecular complexes and saccharide-binding proteins was demonstrated by surface plasmon resonance and agarose gel staining assays. beta-lactoside-appended schizophyllan enhanced an antisense activity in hepatocytes which express lactoside-binding proteins on their cell surfaces. 相似文献
208.
Maezaki N Sawamoto H Yuyama S Yoshigami R Suzuki T Izumi M Ohishi H Tanaka T 《The Journal of organic chemistry》2004,69(19):6335-6340
The first example of an asymmetric intramolecular Michael addition reaction with use of alpha-lithiated vinylic sulfoxide as a Michael donor is reported. Michael addition of the alpha-lithiated vinylic sulfoxide to (Z)-enoates proceeds with high diastereoselectivity to give the adducts with (R)-configuration at the beta-position of the ester in the five-membered-ring formation. The selectivity was reversed in the six-membered-ring formation. The resulting ester enolates were reacted with alkyl halides or benzaldehyde with high diastereoselectivity. 相似文献
209.
Whole body distribution and accumulation of radionuclide for diagnostic purpose such as 99mTc-MDP (methylene diphosphonate), 67Ga-citrate (67Ga) and 201Tl-chloride (201Tl) in implanted osteosarcoma of human origin were evaluated by macroautoradiography of Balb/c nude mouse. 3H-thymidine of which uptake has a close relation to growth pattern of tumors was used for a partner of target nuclide in double tracer technique to examine the distribution characteristics. Separated distribution pattern of coupled nuclides was imaged by a difference both of half life and energy of radiation between radionuclides. The distribution pattern of each target nuclide and 3H-thymidine were compared to clarify distribution characteristics respectively in specimen. 67Ga and 201Tl were taken around the tumor and the mode of their distribution was identical to that of 3H-thymidine. Uptake of 67Ga in tumor was much higher. 99mTc-MDP accumulated in the central zone of the tumor and its pattern was quite different from that of 3H-thymidine. From above result it was demonstrated that the accumulation mechanism of 67Ga, 201Tl and 99mTc-MDP are quite different in the tumor each other. So we concluded that our method of double tracer technique was useful for evaluation of distribution pattern of radionuclides for diagnostic purpose. 相似文献
210.
Kitahara M Umeda N Hirano K Satoh T Miura M 《Journal of the American Chemical Society》2011,133(7):2160-2162
Copper-mediated intermolecular direct biaryl coupling of arylazines and azoles via dual C-H bond cleavage proceeds even without palladium catalysts. The reaction system shows the high potential of copper salts in direct C-H arylation chemistry and provides a new approach to biaryl motifs, which are ubiquitous in pharmaceuticals and functional materials. 相似文献