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981.
982.
983.
Naoyuki Kinoshita Kazunari Domen Ken-ichi Aika Takaharu Onishi 《Applied Surface Science》1984,18(3):342-344
The infrared band of dinitrogen species adsorbed on a Co/Al2O3 catalyst was observed at 2214 cm-1, which shifted in the presence of adsorbed and gaseous hydrogen. 相似文献
984.
Jing Kong Jiurong Liu Fenglong Wang Liqiang Luan Masahiro Itoh Ken-ichi Machida 《Applied Physics A: Materials Science & Processing》2011,105(2):351-354
Large-scale octahedral Fe3O4 nanocrystallines with crystalline size of 100−500 nm were synthesized by a facile solvent-thermal method for electromagnetic
wave application. The Fe3O4 nanocrystallines showed a higher saturation magnetization (M
s
) value of 86.8 emu/g and larger coercivity (H
cj
) value of 255 Oe than that of magnetite polycrystallines because of their good crystallization and dispersion. The epoxy
resin composites with 40 vol% Fe3O4 powders provided good electromagnetic wave absorption performance (RL < −20 dB) in the range of 2.0–4.3 GHz over the absorber
thicknesses of 3.5–6.8 mm. A minimum RL value of −47 dB was observed at 3.1 GHz with a thickness of 4.8 mm. 相似文献
985.
Kanako?Honda Hirofumi?Kawazumi Naotoshi?Nakashima Yasuro?NiidomeEmail author 《Journal of nanoparticle research》2011,13(8):3413-3421
Aggregates of phosphatidylcholine-passivated gold nanorods were prepared by the addition of hydrochloric acid in the presence
of 6-amino-1-hexanethiol hydrochloride (AHT). The aggregates dried in vacuum formed a solid film showing a metallic gold color.
In spite of the absence of the stable surface-wrapping agents, such as balky polymer or thiol-molecules that form stable self-organized
films on a gold surface, the dried aggregates dispersed again in water. The redispersed gold nanorods in water did not form
aggregates. If the dried nanorods were kept at room temperature for 24 h, they did not disperse in water again; however, at
–30 °C, some of gold nanorods could be redispersed in water. At –80 °C, gold nanorods could be redispersed in water as colloidal
nanoparticles even after 2 months. The phosphatidylcholine and AHT molecules on the nanorod surfaces contributed to the suppression
of the contact of nanorods, which were in the metallic gold color films. 相似文献
986.
Transport in Porous Media - The electrical conductivity of porous dielectric materials saturated with water is usually determined by the bulk water conduction. However, the unsaturated state can be... 相似文献
987.
Nakashima S Ando H Imamura A Yuki N Ishida H Kiso M 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(2):588-597
The hybrid ganglioside X1, which was identified in the bovine brain, was synthesized for the first time. Ganglioside X1 is believed to be involved in the development of amyotrophic lateral sclerosis-like disorders in patients with neurological disorders after treatment with bovine brain gangliosides. A convergent approach using two branched glycan units, the GM2-core trisaccharide and the lacto-ganglio tetrasaccharide, efficiently provided the highly branched heptasaccharide part of ganglioside X1, which was conjugated with the ceramide part to produce the protected ganglioside X1. Global deprotection delivered homogenous ganglioside X1, with which serum from the patient was reacted. 相似文献
988.
Ozawa H Fujigaya T Niidome Y Hotta N Fujiki M Nakashima N 《Journal of the American Chemical Society》2011,133(8):2651-2657
Single-walled carbon nanotubes (SWNTs) have remarkable and unique electronic, mechanical, and thermal properties, which are closely related to their chiralities; thus, the chirality-selective recognition/extraction of the SWNTs is one of the central issues in nanotube science. However, any rational materials design enabling one to efficiently extract/solubilize pure SWNT with a desired chirality has yet not been demonstrated. Herein we report that certain chiral polyfluorene copolymers can well-recognize SWNTs with a certain chirality preferentially, leading to solubilization of specific chiral SWNTs. The chiral copolymers were prepared by the Ni(0)-catalyzed Yamamoto coupling reaction of 2,7-dibromo-9,9-di-n-decylfluorene and 2,7-dibromo-9,9-bis[(S)-(+)-2-methylbutyl]fluorene comonomers. The selectivity of the SWNT chirality was mainly determined by the relative fraction of the achiral and chiral side groups. By a molecular mechanics simulation, the cooperative interaction between the fluorene moiety, alkyl side chain, and graphene wall were responsible for the recognition/dissolution ability of SWNT chirality. This is a first example describing the rational design and synthesis of novel fluorene-based copolymers toward the recognition/extraction of targeted (n,?m) chirality of the SWNTs. 相似文献
989.
Minamoto A Neriishi K Nakashima E 《Journal of photochemistry and photobiology. B, Biology》2011,103(2):105-110
Accurate assessment of risk factors is important for the evaluation of radiation-induced ocular lens damage. Our previous study identified a significant city difference between Hiroshima and Nagasaki atomic-bomb survivors in terms of cataract prevalence, prompting further analysis. This study analyzed the sites of lens opacities and used model fitting that incorporated the variable impact of UV on the eye, based on the hypothesis that the city difference in the prevalence of cataract was due to differences in UV radiation between the two cities. The results suggested that cataracts among Nagasaki residents were more frequently located at the inferior nasal portion of the lens compared to cataracts in Hiroshima residents, with no ionizing radiation-specific localization observed. Based on the angles of incidence, UV was suggested as a possible cause of the city difference. We therefore analyzed models of city differences in terms of UVA and UVB levels. The UVB model provided a better fit than the UVA model, suggesting that UVB might account for the city difference. The current study implicated the geographic location of the subject, the investigation period, and outdoor activities as potentially important surrogate factors for UVB influence in radiation-induced cataract. In addition, the superior temporal portion of the lens seemed the most suitable for evaluating the effects of ionizing radiation because of the lesser amount of UVB interference at that site. 相似文献
990.
Ken-ichi Nakashima Masayoshi Oyama Tetsuro Ito Yukihiro Akao Joko Ridho Witono Dedy Darnaedi Toshiyuki Tanaka Jin Murata Munekazu Iinuma 《Tetrahedron》2012,68(10):2421-2428
Six novel quinolinone alkaloids bearing a phenylpropanoid or a coumarin moiety, named melicodenines C–H (1–6), two new cinnamyl alcohol derivatives, named melicodins A (7) and B (8), and a new coumarinolignan, named melicodin C (9), were isolated from the leaves of Melicope denhamii (Seem.) T. G. Hartley. Their structures were established by spectroscopic analyses including extensive 2D-NMR experiments. Compounds 1–5 and 9 possess a cyclobutane ring and are hypothetically produced by a [2+2] cycloaddition, whereas compound 6 is presumed to form through a Diels–Alder cycloaddition followed by the elimination of an acetone molecule. Ten quinolinone alkaloids (1–6, 10–13) and a coumarinolignan (9) were tested for anti-proliferative activity against DLD-1 human colon cancer cells. Melicodenine G (5) showed the most potent inhibitory activity, causing the induction of apoptosis with an IC50 value of 9.4±0.3 μM. 相似文献