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71.
Yoshimi Egawa 《Journal of Combinatorial Theory, Series A》1985,38(1):1-14
A new class of association schemes attached to quadratic forms is obtained. In terms of a graph, those schemes are distance regular but generally not distance transitive. 相似文献
72.
73.
Yoshimi Egawa 《Graphs and Combinatorics》1991,7(1):15-21
It is proved that ifG is ann-connected graph with minimum degree greater than or equal to [5n/4],n 4, thenG has an edgee such that the graph obtained fromG by contractinge is stilln-connected.Dedicated to Professor Nagayoshi Iwahori on his 60th birthday 相似文献
74.
Yuge R Yudasaka M Miyawaki J Kubo Y Ichihashi T Imai H Nakamura E Isobe H Yorimitsu H Iijima S 《The journal of physical chemistry. B》2005,109(38):17861-17867
We succeeded in large-scale preparation of single-wall carbon nanohorns (SWNH) encapsulating C60 molecules in a liquid phase at room temperature using a "nano-precipitation" method, that is, complete evaporation of the toluene from a C60-SWNH-toluene mixture. The C60 molecules were found to occupy 6-36% of the hollow space inside the SWNH, depending on the initial quantity of C60. We showed that the C60 in C60@SWNHox was quickly released in toluene, and the release rate decreased by adding ethanol to toluene. Numerical analysis of the release profiles indicated that there were fast and slow release processes. We consider that the incorporation quantity and the release rate of C60 were controllable in/from SWNHs because SWNHs have large diameters, 2-5 nm. 相似文献
75.
Reduced molybdoantimonylphosphoric acid is extracted into diisobutyl ketone (DIBK) and phosphorus in the extract determined by i.c.p. emission spectrometry at the P I 214.91-nm line. The Mo II 213.61 nm line interfered with the P I 213.62-nm line. The method is applied to 0.2–200 μg of phosphorus in 500 ml of river or sea water. Arsenic(III), Si, Ge, Fe(III) and most anions do not interfere, but As(V) >10 × P) causes positive errors. The detection limit is 0.37 ng P ml-1, and the relative standard deviation for 5 μg of phosphorus is 2.1%. 相似文献
76.
On the basis of the change in electronic and induced circular dichroism spectra for complex formation, the complexation of 4‐dimethylaminoazobenzene (DAAB) with four kinds of cyclodextrins (α‐ and β‐cyclodextrin (CD), heptakis(2,6‐di‐O‐methyl)‐β‐cyclodextrin, and heptakis(2,3,6‐tri‐O‐methyl)‐β‐cyclodextrin) was studied in methanol–water and dimethyl sulfoxide–water mixtures. It was found that the trans and cis isomers of DAAB form two different types of complex (inclusion and lid type) with CDs, depending on the kinds of CDs and solvents. Further, we have examined the effect of CDs on the thermal cis‐to‐trans isomerization of DAAB. The accelerated or decelerated effect on the thermal isomerization was observed upon adding CDs. The effects of CDs on the thermal isomerization are discussed in connection with the complexation of the cis‐isomer of DAAB with CDs. © 2002 Wiley Periodicals, Inc. Int J Chem Kinet 34: 481–487, 2002 相似文献
77.
Kamiya S Shirahase H Yoshimi A Nakamura S Kanda M Matsui H Kasai M Takahashi K Kurahashi K 《Chemical & pharmaceutical bulletin》2000,48(6):817-827
We synthesized a series of indoline derivatives with an amide or urea moiety and examined their inhibitory effects on acyl-CoA:cholesterol acyltransferase (ACAT) activity, lipid-peroxidation and serum cholesterol levels in experimental animals. Among the derivatives synthesized, a series of N-(1-alkyl-4,6-dimethylindolin-7-yl)-2,2-dimethylpropanamides++ + potently inhibited rabbit intestinal ACAT activity and lipid-peroxidation of rat brain homogenate. The effect on ACAT activity was related to the length of the alkyl chain at the 1-position of indoline. N-(4,6-Dimethyl-1-octylindolindolin-7-yl)-2,2-dimethylpropanami de hydrochloride (55) showed inhibitory effects on intestinal and hepatic ACAT activity slightly weaker than those of YM-750, and an inhibitory effect on low density lipoprotein (LDL)-peroxidation similar to that of probucol. Compound 55 also reduced serum cholesterol at 10 mg/kg/d in hyperlipidemic rats and 20 mg/kg/d in normolipidemic hamsters. The plasma concentration of 55 reached 716 ng/ml in dogs (10 mg/kg, p.o.), which is an effective concentration against hepatic ACAT activity and LDL-peroxidation. In conclusion, compound 55 is a novel bioavailable ACAT inhibitor with anti-peroxidative activity and is thus a promising anti-atherosclerotic and anti-hyperlipidemic drug. Indoline proved to be a useful pharmacophore for molecular design of new anti-peroxidative drugs. 相似文献
78.
Tsuneo Okubo Akira Tsuchida Hideki Yoshimi Kazumori Taguchi Shigeharu Kiriyama 《Colloid and polymer science》2002,280(3):228-233
Rotational relaxation times (τ) of anisotropic tungstic acid colloids (3.24 μm in major axis) in aqueous suspension are measured in microgravity (0G), normal gravity (1G) and at 2G. The measurements at 0G and 2G are achieved by parabolic and circular flights, respectively. The limiting slopes of the relaxation curves in the plots of
the transmitted light intensity against time are close to zero at 0G irrespective of the flow directions in the flow cell, whereas those at 1G and especially at 2G depend on the flow direction by the convection of the suspension and particle sedimentation. Experimental errors at the τ
values at 0G are small compared with those at 1G and 2G, which is ascribed to the lack of movement of impurities in the suspension such as quite small air bubbles, which cannot
be recognized with the naked eye, and the convection of the suspension in microgravity. More reliable rotational relaxation
times are obtained in microgravity; however, the relaxation times themselves are quite insensitive to gravity. Theτ values observed are larger than those calculated from the particle size, which indicates the important contribution of the
electrical double layers formed around the colloidal particles.
Received: 22 February 2001 Accepted: 13 June 2001 相似文献
79.
Ryohei Sugita Natsuko I. Kobayashi Atsushi Hirose Yoshimi Ohmae Keitaro Tanoi Tomoko M. Nakanishi 《Journal of Radioanalytical and Nuclear Chemistry》2013,298(2):1411-1416
We have developed a real-time radioisotope imaging system (RRIS) that can nondestructively trace 14C-labeled chemicals in plants. In an experiment, after feeding 14CO2 to a plant, the plant was fixed inside a box where lighting was regulated, and beta rays emitted from the 14C in the plant were intermittently imaged using the developed system. As a first step, using a series of standard sources of 14C, the data depth and detection limits of the 14C images captured by the RRIS were evaluated for various integral times. As a result, the linearity between the 14C activity and signal intensity was determined for the range 103. Next, the linearity was validated using plant (Arabidopsis thaliana) organs, resulting that the linearity was shown in the case of young leaf, but was not maintained in the thick organs, such as a flower, mature leaf, siliques, and stem. Considering the good correlation between the intensity by RRIS and the PSL value by an imaging plate (IP) as well as the relative low energy of beta rays emitted from 14C, the thickness of the organs would easily affect the quantitativity of the RRIS as well as an IP. Our findings prove that sequential images of 14C in a living plant sample in a regulated light and air environment can be nondestructively analyzed using the developed system, whose quantitativity is similar to that of an IP. 相似文献
80.
Yoshimi Kurimura Eishun Tsuchida Masao Kaneko 《Journal of polymer science. Part A, Polymer chemistry》1971,9(12):3511-3519
Water-soluble cobalt(III) chelates having a polymeric ligand such as cis-[Co(en)2-PVPCl]Cl2 and cis-[Co-(trien)PVPCl]Cl2 (PVP = poly-4-vinylpyridine) were prepared by substitution reactions between cobalt(III) chelate and PVP in water–alcohol solution. PVP of different degrees of polymerization was used as the ligand in preparation of these complexes. The PVP complexes were identified and their properties ascertained by microanalysis and by a study of the infrared, ultraviolet, visible, and PMR spectra. Most of the characteristic properties of these complexes may be ascribed to the polymeric structure of the PVP ligand. 相似文献