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821.
Prof. Dr. Ryo Sekiya Yuichiro Uemura Prof. Dr. Hideki Murakami Prof. Dr. Takeharu Haino 《Angewandte Chemie (International ed. in English)》2014,53(22):5619-5623
Graphene quantum dots (GQDs) have received considerable attention for their potential applications in the development of novel optoelectronic materials. In the generation of optoelectronic devices, the development of GQDs that are regulated in terms of their size and dimensions and are unoxidized at the sp2 surfaces is desired. GQDs functionalized with bulky Fréchet’s dendritic wedges at the GQD periphery were synthesized. The single‐layered, size‐regulated structures of the dendronized GQDs were revealed by atomic force microscopy. The edge‐functionalization of the GQDs led to white‐light emission, which is an uncommon feature. 相似文献
822.
Effect of Photoinduced Size Changes on Protein Refolding and Transport Abilities of Soft Nanotubes
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Dr. Naohiro Kameta Dr. Haruhisa Akiyama Dr. Mitsutoshi Masuda Dr. Toshimi Shimizu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(21):7198-7205
Self‐assembly of azobenzene‐modified amphiphiles (GlynAzo, n=1–3) in water at room temperature in the presence of a protein produced nanotubes with the protein encapsulated in the channels. The Gly2Azo nanotubes (7 nm internal diameter [i.d.]) promoted refolding of some encapsulated proteins, whereas the Gly3Azo nanotubes (13 nm i.d.) promoted protein aggregation. Although the 20 nm i.d. channels of the Gly1Azo nanotubes were too large to influence the encapsulated proteins, narrowing of the i.d. to 1 nm by trans‐to‐cis photoisomerization of the azobenzene units of the Gly1Azo monomers packed in the solid bilayer membranes led to a squeezing out of the proteins into the bulk solution and simultaneously enhanced their refolding ratios. In contrast, photoinduced transformation of the Gly2Azo nanotubes to short nanorings (<40 nm) with a large i.d. (28 nm) provided no further refolding assistance. We thus demonstrate that pertubation by the solid bilayer membrane wall of the nanotubes is important to accelerate refolding of the denatured proteins during their transport in the narrow nanotube channels. 相似文献
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826.
Yuichiro Fujiwara 《组合设计杂志》2005,13(4):286-291
In this paper, we present a recursive construction for anti‐mitre Steiner triple systems. Furthermore, we present another construction of anti‐mitre STSs by utilizing 5‐sparse ones. © 2004 Wiley Periodicals, Inc. 相似文献
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828.
Monte Carlo approaches to compute multiple scattering of polarized light are examined. A Backward Monte Carlo (BMC) method is developed to solve the Stokes vector of the multiple scattered light for an inhomogeneous scattering medium with boundaries. A generalized form of the BMC method in vector notation is proposed. This method can determine the scattered light with sufficient accuracy in both intensity and polarization compared to the same calculation using the doubling-adding method for a plane parallel medium.For application to a narrow incident beam and an inhomogeneous medium, a modified BMC method is developed, borrowing a concept from the Forward Monte Carlo (FMC) method for the first scattering events. Furthermore, a modification of the total scattering matrix, i.e., the combination of the derived scattering matrix with its time inverse, is discussed. This BMC method can be used successfully for model calculations of lidar and other laser measurements of polarized light. 相似文献
829.
The study was undertaken to investigate possible teratogenic effects of a high magnetic field on fetal development in mice. Eighty-four pregnant CD-1 mice (ICR) were exposed to a static magnetic field of 6.3 T for 1 hr a day from day 7 through day 14 of gestation, a period corresponding to major organogenesis. Fifty mice served as controls. Dams were sacrificed on day 18 of gestation. Fetuses were examined for both external and skeletal abnormalities. No significant differences between exposed and control groups were observed regarding litter size, fetal weight, intrauterine mortality rate, or external and skeletal anomalies. The effects of static magnetic field of 6.3 T on the parameters studied appear negligible. 相似文献
830.
Yuichiro Fujiwara 《Journal of Algebraic Combinatorics》2007,26(4):495-506
In 1973 Paul Erdős conjectured that there is an integer v
0(r) such that, for every v>v
0(r) and v≡1,3 (mod 6), there exists a Steiner triple system of order v, containing no i blocks on i+2 points for every 1<i≤r. Such an STS is said to be r-sparse. In this paper we consider relations of automorphisms of an STS to its sparseness. We show that for every r≥13 there exists no point-transitive r-sparse STS over an abelian group. This bound and the classification of transitive groups give further nonexistence results
on block-transitive, flag-transitive, 2-transitive, and 2-homogeneous STSs with high sparseness. We also give stronger bounds
on the sparseness of STSs having some particular automorphisms with small groups. As a corollary of these results, it is shown
that various well-known automorphisms, such as cyclic, 1-rotational over arbitrary groups, and involutions, prevent an STS
from being high-sparse.
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