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991.
A new furopyranone, phellifuropyranone A, was isolated from fruit bodies of wild Phellinus linteus as well as phelligridin G, and their chemical structures were determined by various spectroscopic methods including measurement of NMR spectra. Phellifuropyranone A together with meshimakobnol A and meshimakobnol B showed antiproliferative activity against mouse melanoma cells and human lung cancer cells in vitro. 相似文献
992.
We study composition operators on the space of bounded harmonic functions on the open unit disk. The principal goal of this
paper is to provide criteria for determining the essential norm of difference of two composition operators.
The third author is partially supported by Grant-in-Aid for Scientific Research (No.17540169), Japan Society for the Promotion
of Science. 相似文献
993.
Gemini-type hybrid surfactants with two fluorocarbon chains connected through a hydrocarbon spacer, F(CF2)m(CH2)2CH(OSO3Na)(CH2)nCH(OSO3Na)(CH2)2(CF2)mF [Fm(Hn)FmOS, m = 4, 6; n = 5, 6, 7, 8)], were synthesized and their surface chemical properties were examined with the aim to have highly functional and highly water-soluble fluorinated surfactants when compared with the conventional fluorinated surfactants. Comparisons of the surface chemical properties of the synthesized gemini-type hybrid surfactants with those of monounit-type hybrid surfactants, F(CF2)m(CH2)2CH(OSO3Na)(CH2)nH [FmEHnOS, m = 4, 6; n = 3, 5)], revealed that gemination causes a remarkable lowering (about 1/100) in cmc value while it produces little changes in Krafft point (below 0 °C) and surface tension at cmc (γcmc). 相似文献
994.
Jenkins in 2003 showed that every odd perfect number is divisible by a prime exceeding . Using the properties of cyclotomic polynomials, we improve this result to show that every perfect number is divisible by a prime exceeding .
995.
Kentaro Nishiyama Hiroki Akiba Satoshi Nagata Kouhei Tsumoto Haruhiko Kamada Hiroaki Ohno 《Angewandte Chemie (International ed. in English)》2023,62(30):e202306431
Proximity-induced chemical reactions are site-specific and rapid by taking advantage of their high affinity and highly selective interactions with the template. However, reactions induced solely by antibody–antigen interactions have not been developed. Herein, we propose a biepitopic antigen-templated chemical reaction (BATER) as a novel template reaction. In BATER, reactive functional groups are conjugated to two antibodies that interact with two epitopes of the same antigen to accelerate the reaction. We developed a method for visualizing the progress of BATER using fluorogenic click chemistry for optimal antibody selection and linker design. The reaction is accelerated in the presence of a specific antigen in a linker length-dependent manner. The choice of the antibody epitope is important for a rapid reaction. This design will lead to various applications of BATER in living systems. 相似文献
996.
Parallel twin boundaries arranged at similar intervals of nanometer length, that emitted an intense monochromatic light polarized parallel to the boundaries, were self-organized in an indirect-gap AlGaAs epilayer; the epilayer was grown on a rough As-deficient surface of an AlGaAs(0 0 1) substrate with any lattice constant, by conventional metal-organic chemical-vapor deposition. Most boundaries were of -type on B, and they extended from the interface between the epilayer and the substrate. There existed no compositional fluctuation around the boundaries. The formation mechanism was discussed. 相似文献
997.
Nara J Kajiyama H Hashizume T Suwa Y Heike S Matsuura S Hitosugi T Ohno T 《Physical review letters》2008,100(2):026102
The formation mechanism of one-dimensional Si islands on a H/Si(001)-(2x1) surface is studied using scanning tunneling microscopy/spectroscopy and first-principles calculations. We observed that one-dimensional islands that are made from dimer chains are formed at the initial growth stages similar to the bare Si(001) surface. It is found that the number of odd-numbered dimer chains is larger than that of even-numbered dimer chains. We propose the growth processes of the two types of growth edges to explain the observation. 相似文献
998.
999.
1000.
We give a generating function for the sums of multiple zeta values of fixed weight, depth and height in terms of Riemann zeta values. 相似文献