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111.
The characteristic energy band values such as the Fermi-level position with respect to valence band top for a boron-doped p-type hydrogen-terminated chemical-vapor-deposition (CVD) diamond (0 0 1)2 × 1 surface and for a clean CVD diamond (0 0 1)2 × 1 surface have been determined by a new method with an accuracy of ±0.02 eV. The electron attenuation length for the clean diamond (0 0 1)2 × 1 surface for the electron kinetic energy of C 1s X-ray photoemission peak by Mg Kα excitation is experimentally determined to be 2.1-2.2 nm. These values are compared and discussed with the previously reported experimental and simulation values. 相似文献
112.
Kaneko T Clark RS Ohi N Kawahara T Akamatsu H Ozaki F Kamada A Okano K Yokohama H Muramoto K Ohkuro M Takenaka O Kobayashi S 《Chemical & pharmaceutical bulletin》2002,50(7):922-929
During a search for novel, orally-active inhibitors of upregulation of adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1), we found a new series of 10H-pyrazino[2,3-b][1,4]benzothiazine derivatives to be potent ICAM-1 inhibitors. Of these compounds, N-[1-(10H-Pyrazino[2,3-b][1,4]benzothiazin-8-ylmethyl)piperidin-4-yl]-N',N'-dimethylsulfamide 7p showed the potent oral inhibitory activities against neutrophil migration in a murine interleukin-1 (IL-1) induced paw inflammation model. The synthesis and structure-activity relationships of these amide derivatives are described. 相似文献
113.
Akio Honda Hiroshi Shibata Jiro Gyoba Kouji Saitou Yukio Iwaya Yôiti Suzuki 《Applied Acoustics》2007,68(8):885-896
Transfer effects of playing an auditory game with a virtual auditory display (VAD) were investigated. Furthermore, we analyzed the effects of playing the VAD game on sound localization performance under subjects’ own head-related transfer functions (HRTFs) and HRTFs fitted from those of 16 other adults. Participants performed sound localization tasks initially and 2 weeks later to show the effects. The VAD game players were of three groups, using own HRTFs, fitted HRTFs, and no playing (control). The VAD game-playing results revealed that: (1) the hit rate of the sound localization task for real sound sources increased approximately 20%; (2) the vertical and horizontal localization error decreased significantly; (3) sound localization performance using fitted HRTFs was similar to performance using own HRTFs. Follow-up tests revealed that transfer effects persisted more than 1 month, suggesting that the effects of playing the VAD game transfer to sound localization performance. 相似文献
114.
Nagashima F Kasai W Kondoh M Fujii M Watanabe Y Braggins JE Asakawa Y 《Chemical & pharmaceutical bulletin》2003,51(10):1189-1192
Two new ent-kaurene-type and a new rearranged ent-kaurene-type diterpenoids possessing cytotoxicity against a human leukemia cell line have been isolated from the New Zealand liverwort Jungermannia species, together with previously known ent-kaurene-type diterpenoids. Their structures were established based on extensive NMR techniques. 相似文献
115.
Michi-Hiko Mannami Kazumasa Narumi Fumihiro Katoh Yoshikazu Fujii Kenji Kimura 《Radiation Physics and Chemistry》1997,49(6):623-629
Experimental findings of glancing-angle scattering of energetic ions are reviewed with particular emphasis on the energy loss of ion during scattering. The position-dependent stopping power of the surface which is derived from the angular dependence of observed energy loss is explained in terms of single and distance electron excitations of surface electrons. For the ions with velocities less than the Fermi velocity of target valence electrons, it is shown that the stopping power of a surface is determined only by the elastic collisions of the ion with valence electrons. From the analysis of the energy losses of 12–30 keV He ions reflected from the (001) surface of SnTe, a method is proposed to derive the electron density distribution averaged over the plane parallel to the surface from this position-dependent stopping power. 相似文献
116.
Nobuyuki Mase Shunsuke Mori Jun Ishizuka Fumihiro Kumazawa Shoji Yamamoto Kohei Sato Tetsuo Narumi 《Tetrahedron letters》2018,59(50):4392-4396
The synthesis of poly-l-lactide (PLLA) in supercritical carbon dioxide (scCO2) was accomplished using an organocatalyst. The reaction proceeded smoothly under CO2 plasticizing polymerization (CPP) conditions at a lower temperature than those conventionally employed. This method allowed the formation of high-molecular-weight, pure PLLA, and therefore has the potential to reduce energy consumption and minimize production costs. Our method is non-toxic and efficient, affording a high-quality product while complying with volatile organic compound regulations. We can produce PLLA that meets the increasing standards (safety and high functionality) of the medical sector, while being applicable to full-scale industrial manufacturing and academic research. 相似文献
117.
Akira Miyazawa Kaori Saitou Thomas M. Gädda G.K. Surya Prakash 《Tetrahedron letters》2006,47(9):1437-1439
Upon microwave irradiation in water, Pt/C converts primary amines into secondary amines in good yield via retro-reductive and reductive amination. 相似文献
118.
Cell-Specific Gene Transfer by α-Cyclodextrin Conjugates with Mannosylated Polyamidoamine Dendrimers
Hidetoshi Arima Koki Wada Fumihiro Kihara Toshihito Tsutsumi Fumitoshi Hirayama Kaneto Uekama 《Journal of inclusion phenomena and macrocyclic chemistry》2002,44(1-4):361-364
To improve the activity and the cell specificity of gene transferof polyamidoamine starburst dendrimer, we prepared -CyD conjugates with mannosylateddendrimers (generation 2 (G2), man--CDE conjugates) having various degrees of substitution(DS) of mannose residue. The man--CDE conjugates (DS 1, 3 and 5) formed complexeswith plasmid DNA (pDNA), but man--CDE conjugate (DS 8) did not. The gene transferactivity of man--CDE conjugates (DS 1, 3 and 5) and -CDE conjugate was augmented with an increasein the charge ratio of vector/pDNA, without showing cytotoxicity. Man--CDE conjugates(DS 3 and 5) showed higher gene transfer activity than -CDE conjugate in A549 cells, whichrecognize mannose, but man--CDE conjugates (DS 1 and 8) showed almost comparable gene transfer activityto -CDE conjugate (G2). On the other hand, no appreciable enhancing effect of man--CDEconjugates (DS 3 and 5) on the transfer activity was observed in NIH3T3 cells, which do not recognizemannose. These findings suggest that man--CDE conjugates (DS 3 and 5) can be new preferablecell-specific non-viral vectors of pDNA to cells which recognize the mannose moiety. 相似文献
119.
Kazuhiro Yoshida Fumihiro Kawagoe Noriyuki Iwadate Hidetoshi Takahashi Tsuneo Imamoto 《化学:亚洲杂志》2006,1(4):611-613
Benzene derivatives were synthesized in excellent yield from 1,4,7‐trien‐3‐ols by tandem ruthenium‐catalyzed ring‐closing olefin metathesis (RCM)/dehydration. The method was extended to the tandem RCM/oxidation process to obtain phenol and aniline derivatives. This method displays many advantages over aromatic‐substitution‐based classical routes. 相似文献
120.
Complete mitochondrial DNA sequence of a tadpole shrimp (Triops cancriformis) and analysis of museum samples 总被引:2,自引:0,他引:2
Umetsu K Iwabuchi N Yuasa I Saitou N Clark PF Boxshall G Osawa M Igarashi K 《Electrophoresis》2002,23(24):4080-4084
The complete mitochondrial DNA (mtNDA) of the tadpole shrimp Triops cancriformis was sequenced. The sequence consisted of 15,101 bp with an A+T content of 69%. Its gene arrangement was identical with those sequences of the water flea (Daphnia pulex) and giant tiger prawn (Penaeus monodon), whereas it differed from that of the brine shrimp (Artemia franciscana) in the arrangement of its genes for tRNAs. Phylogenetic analysis revealed T. cancriformis to be more closely related to the water flea than to the brine shrimp and giant tiger prawn. We also compared the 16S rRNA sequences of five formalin-fixed tadpole shrimps that had been collected in five different locations and stored in a museum. The sequence divergence was in the range of 0-1.51%, suggesting that those samples were closely related to each other. 相似文献