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211.
The notion of unbiased orthogonal designs is introduced as a generalization of unbiased Hadamard matrices, unbiased weighing matrices and quasi-unbiased weighing matrices. We provide upper bounds and several methods of construction for mutually unbiased orthogonal designs. As an application, mutually quasi-unbiased weighing matrices for various parameters are obtained. 相似文献
212.
213.
Journal of Algebraic Combinatorics - The notion of disjoint weighing matrices is introduced as a generalization of orthogonal designs. A recursive construction along with a computer search leads to... 相似文献
214.
Sho Tanaka 《Foundations of Physics Letters》2006,19(6):567-578
Motivated by the recent proposition by Buniy, Hsu, and Zee with respect to discrete spacetime and finite spatial degrees of
freedom of our physical world with short- and long-distance scales, l
P
and L, we reconsider the Lorentz-covariant Yang's quantized spacetime algebra (YSTA), which is intrinsically equipped with two
such kinds of scale parameters, λ and R. In accordance with their proposition, we find the so-called contracted representation of YSTA with finite spatial degrees
of freedom associated with the ratio R/λ, which gives a possibility of the divergence-free noncommutative field theory on YSTA. The canonical commutation relations
familiar in the ordinary quantum mechanics appear as the cooperative Inonu-Wigner's contraction limit of YSTA, λ → 0 and R → ∓. 相似文献
215.
Feasibility of carboxymethylcellulose with phenol moieties as a material for mammalian cell-enclosing subsieve-size capsules 总被引:1,自引:0,他引:1
Shinji Sakai Sho Ito Yuko Ogushi Ichiro Hashimoto Koei Kawakami 《Cellulose (London, England)》2008,15(5):723-729
Mammalian cell-enclosing capsules have been investigated as devices for bioproduction, cell therapy and stem cell research.
In this study, carboxymethylcellulose (CMC) with phenol moieties (CMC-Ph), synthesized through the conjugation reaction of
CMC and tyramine, was investigated as a material for these types of devices. Subsieve-size capsules of less than 100 μm in
diameter were prepared by extruding aqueous CMC-Ph solution into co-flowing liquid paraffin containing H2O2. The capsule diameter was controlled between 60–220 μm by changing the flow rate of liquid paraffin. There was no harmful
effect specific for CMC-Ph on mammalian cells enclosed in capsules. Feline kidney cells enclosed in subsieve-size CMC-Ph capsules
exhibited 87.0 ± 4.5% viability. In addition, the enclosed cells continued to grow over 13 days of study. These results demonstrated
the feasibility of CMC-Ph as a material for subsieve-size cell-enclosing capsules prepared via the droplet breakup technique
in a co-flowing water-immiscible fluid. 相似文献
216.
Yan Yong Sho Han-Ru Li De-Xin Li Guo-Dong Li Dong-Shen Zhen Jin-Shan 《Hyperfine Interactions》1986,28(1-4):635-638
Fe-xCr-8Co (x=24, 25, 27, 29 and 32 wt%) permanent magnetic alloys have been studied bv Mössbauer effect, magnetic balance and vibrating-sample magnetometer. It is indicated that the optimum permanent magnetic properties obtained for the composition of the alloys at about x=27. The value of Cr content in these alloys sigificantly influences the average hyperfine field, the saturation magnetic moment, the proportion of paramagnetic phase and orientation of magnetic moment in these alloys. The intrinsic coercive force is gradually reduced with the temperature decreasing from 290 to 77k. The paramagnetic peak in the spectrum disappars at about 125k. The certain mechanism has been suggested to explain the experimental results. 相似文献
217.
The La ordering and domain structures of La2/3 ? xLi3xTiO3 single crystals and quenched samples have been observed by high resolution electron microscopy. In single crystals, the grown single crystals are not real single crystals with mono-domain, but crystals with 90° oriented domains with 20–100 nm sizes. A remarkable difference of the domain size between polycrystals and single crystals has not been observed at the same composition. In quenched samples, the La disordering has been observed. Furthermore, domain structures of quenched samples are different from those of furnace-cooled ones. Domain structures change with the La disordering. The understanding of microstructures is necessary to clarify the Li-ion conduction mechanism. 相似文献
218.
Mitsunori Honda Sho Sasaki Tsuyoshi Nishimoto Hiromoto Koshiro Ko-Ki Kunimoto Masahito Segi 《Tetrahedron letters》2018,59(42):3777-3781
The synthesis of cyclopropyl silyl ketones possessing a hydrocarbon group at 1-position of three-membered ring was investigated. The reaction of sulfoxonium ylide with α,β-unsaturated acylsilanes derived from α,β-unsaturated aldehydes did not afford the desired acylsilane derivatives. Instead, the corresponding silyl enol ethers were yielded exclusively. On the other hand, the Corey-Chaykovsky cyclopropanation of α-substituted α,β-unsaturated aldehydes proceeded well to give 1-substituted cyclopropyl aldehydes. The silyl substitution of formyl proton in the obtained aldehydes via umpolung of carbonyl group afforded the target acylsilanes. 相似文献
219.
Prof. Dr. Masaya Nakajima Sho Nagasawa Koki Matsumoto Takahito Kuribara Dr. Atsuya Muranaka Prof. Dr. Masanobu Uchiyama Prof. Dr. Tetsuhiro Nemoto 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(17):6914-6919
According to the Grotthuss–Draper law, light must be absorbed by a substrate to initiate a photoreaction. There have been several reports, however, on the promotion of photoreactions using hypervalent iodine during irradiation with light from a non-absorbing region. This contradiction gave rise to a mystery regarding photoreactions involving hypervalent iodine. We demonstrated that the photoactivation of hypervalent iodine with light from the apparently non-absorbing region proceeds via a direct S0→Tn transition, which has been considered a forbidden process. Spectroscopic, computational, and synthetic experimental results support this conclusion. Moreover, the photoactivation mode could be extended to monovalent iodine and bromine, as well as bismuth(III)-containing molecules, providing new possibilities for studying photoreactions that involve heavy-atom-containing molecules. 相似文献
220.
Sho Takemori 《Journal of Number Theory》2012,132(6):1203-1264
We prove an explicit formula for Fourier coefficients of Siegel–Eisenstein series of degree two with a primitive character of any conductor. Moreover, we prove that there exists the p-adic analytic family which consists of Siegel–Eisenstein series of degree two and a certain p-adic limit of Siegel–Eisenstein series of degree two is actually a Siegel–Eisenstein series of degree two. 相似文献