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81.
Bis(azafulvene) derivative of gem-dimethyldipyrrylmethane reacted with 2,2′-bipyrrole under neutral conditions without catalyst to give a mixture of expanded isocorroles in ca. 50% total yields. GPC separation gave eleven porphyrinoids containing 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, and 44 units of pyrrole. 相似文献
82.
H Miyamoto H Ueda T Otsuka S Aki H Tamaoka M Tominaga K Nakagawa 《Chemical & pharmaceutical bulletin》1990,38(9):2472-2475
A series of substituted 4-oxoquinoline-3-carboxylic acids having a methyl group at the 8-position was prepared and tested for their antibacterial activity. 7-(trans-3-Amino-4-methyl-1-pyrrolidinyl)-1-cyclopropyl-1,4-dihydro-6- fluoro-8-methyl-4-oxoquinoline-3-carboxylic acid (21) exhibited highly potent antibacterial activity against both gram-positive and gram-negative bacteria, including Pseudomonas aeruginosa. 相似文献
83.
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85.
Effects of Motion, Implied Direction and Displacement of a Large-Visual-Stimulus on Postural Control
Effects of motion, implied direction in a static stimulus and displacement on postural control were examined independently.
In Experiment 1, rotation of a random-dot stimulus was presented. In Experiments 2 and 3, photographic slides of natural scenes
were used; participants closed their eyes during stimulus rotation to eliminate motion information. In Experiment 2, the stimulus
was presented upright initially, then presented again with a tilt. In Experiment 3, the order was reversed to separate the
effects of implied direction and displacement. Results showed that all information of motion, implied direction, and displacement
had some effect on postural control, although visual information of motion has been presumed to have a principal effect on
postural control. Results suggested that the effects of implied direction might reflect an immediate processing of information.
The effects of displacement and motion might reflect a continuous processing of information. 相似文献
86.
87.
Guijun Ma Yohichi Suzuki Rupashree Balia Singh Aki Iwanaga Yosuke Moriya Tsutomu Minegishi Jingyuan Liu Takashi Hisatomi Hiroshi Nishiyama Masao Katayama Kazuhiko Seki Akihiro Furube Taro Yamada Kazunari Domen 《Chemical science》2015,6(8):4513-4518
The particulate semiconductor La5Ti2CuS5O7 (LTC) with a band gap energy of 1.9 eV functioned as either a photocathode or a photoanode when embedded onto Au or Ti metal layers, respectively. By applying an LTC/Au photocathode and LTC/Ti photoanode to, respectively, photoelectrochemical (PEC) water reduction and oxidation concurrently, zero-bias overall water splitting was accomplished under visible light irradiation. The band structures of LTC/Au and LTC/Ti calculated using a semiconductor device simulator (AFORS-HET) confirmed the critical role of the solid/solid junction of the metal back contact in the charge separation and PEC properties of LTC photoelectrodes. The prominently long lifetime of photoexcited charge carriers in LTC, confirmed by transient absorption spectroscopy, allowed the utilization of both photoexcited electrons and holes depending on the band structure at the solid/solid junction. 相似文献
88.
The rotor‐router model, also known as the Propp machine, is a deterministic process analogous to a random walk on a graph. Instead of distributing tokens to randomly chosen neighbors, the Propp machine deterministically serves the neighbors in a fixed order by associating to each vertex a “rotor‐router” pointing to one of its neighbors. This paper investigates the discrepancy at a single vertex between the number of tokens in the rotor‐router model and the expected number of tokens in a random walk, for finite graphs in general. We show that the discrepancy is bounded by O (mn) at any time for any initial configuration if the corresponding random walk is lazy and reversible, where n and m denote the numbers of nodes and edges, respectively. For a lower bound, we show examples of graphs and initial configurations for which the discrepancy at a single vertex is Ω(m) at any time (> 0). For some special graphs, namely hypercube skeletons and Johnson graphs, we give a polylogarithmic upper bound, in terms of the number of nodes, for the discrepancy. © 2014 Wiley Periodicals, Inc. Random Struct. Alg., 46,739–761, 2015 相似文献
89.
In this article, waiting time distributions of compound patterns are considered in terms of the generating function of the
numbers of occurrences of the compound patterns. Formulae for the evaluation of the generating functions of waiting time are
given, which are very effective computational tools. We provide several viewpoints on waiting time problems associated with
compound patterns and develop a general workable framework for the study of the corresponding distributions. The general theory
is employed for the investigation of some examples in order to illustrate how the distributions of waiting time can be derived
through our theoretical results.
This research was partially supported by the ISM Cooperative Research Program (2006-ISM·CRP-2007). 相似文献
90.
Masaaki Kijima Teruyoshi Suzuki Keiichi Tanaka 《Mathematical Methods of Operations Research》2009,69(3):439-455
We propose a structural model with a joint process of tangible assets (marker) and firm status for the pricing of corporate
securities. The firm status is assumed to be latent or unobservable, and default occurs when the firm status process reaches
a default threshold at the first time. The marker process is observable and assumed to be correlated with the latent firm
status. The recovery upon default is a fraction of tangible assets at the time of default. Our model can evaluate both the
corporate debt and equity to fit their market prices in a unified framework. When the two processes are perfectly correlated,
our model is reduced to the seminal Black–Cox model. Numerical examples are given to support the usefulness of our model.
A previous version of this paper was presented at the Tsukuba–Stanford workshop held at Stanford University on March 2006.
The authors are grateful to participants of the workshop for helpful discussions. 相似文献