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排序方式: 共有1338条查询结果,搜索用时 625 毫秒
871.
Masaki Tsujimoto Tomoki Yabutani Atsushi Sano Yuji Tani Hiroki Murotani Yuji Mishima Kenichi Maruyama Mikito Yasuzawa Junko Motonaka 《Analytical sciences》2007,23(1):59-63
A glucose sensor was developed by electrocopolymerization using pyrroles containing a tris-bipyridine (bpy) osmium complex (Os-py), pyrrole (py), pyrrole propanoic acid (PPA) and glucose oxidase (GOx) to improve the key performance characteristics, such as the sensitivity, selectivity, and long-term stability. Tris-bipyridine osmium pyrrole complexes with four different methylene moieties were utilized to correlate the methylene length with the glucose sensor performance. The electrocatalytic response of glucose was clearly observed at electrodes modified with Os-py, except for the electrode immobilized with the Os-py complex containing the shortest methylene moiety. The current response to glucose increased up to a concentration of 100 mmol dm(-3). The electrocatalytic response to glucose at the [Os(bpy)(2)(py(6)-bpy)](2+/3+)/py/PPA/GOx electrode was stable for more than 100 days. Dissolved oxygen and potential interference compounds (ascorbic acid, uric acid, and acetaminophen) minimally perturbed the current response to glucose at the [Os(DM-bpy)(2)(py(6)-bpy)](2+/3+)/py/PPA/GOx electrode. Based on these results, a longer methylene moiety appears to improve the performance characteristics of a glucose sensor fabricated via the electropolymerization of tris-bipyridine osmium pyrrole complexes. 相似文献
872.
Yoshiaki Nakanishi Michiaki Sumita Kaoru Yumita Takashi Yamada Takaharu Honjo 《Analytical sciences》2004,20(1):73-78
Alga as Achnanthes minutissima among diatoms is a widely adaptable taxon on the state of an aquatic environment. In this study, it was found that diatom had a specific tolerance to heavy metals (Cu, Zn, Pb, and Cd etc.) in river water samples, because the diatom assemblage consisted of almost only Achnanthes minutissima in Kakehashi river and Godani river, which were polluted with waste water from Ogoya copper mine. The relationship between the concentrations of heavy metals (Cu, Zn, Pb and Cd) in river water and the attached substances (algae and silt etc.) and the relative abundances of diatom taxa were investigated in detail. The results indicated that the higher is the concentration of heavy metals in the river environment, the higher is only the relative abundances of Achnanthes minutissima. Thus, the taxon can be used as a bioindicator of heavy metal pollution. The relative rates of toxic chemical forms of copper in algae were 61 - 92% in the attached substances and 49-70% in the sediment on the river bed, respectively. Therefore, it was found that diatom as Achnanthes minutissima had a tolerance to heavy metals in river water, being able to live in such an environment. Since the water treated with calcium hydroxide from the deposition reservoir of Ogoya mine enters in Godani river, the river is polluted by heavy metals (Cu, Zn, Pb and Cd etc.). From the viewpoint of both biological and chemical analyses, Godani river is still polluted with heavy metals, because their concentrations in the river samples were very high. On the other hand, in Kakehashi river, the concentrations of heavy metals were very low and the distributions of some diatoms appeared in an unpolluted Nishimata river were observed. Therefore, Kakehashi river seems to be considerably recovered from heavy-metal pollution after closing the Ogoya mine. 相似文献
873.
Toshitaka Nakamura Hironaka Fujii Noriyuki Juni Sadahiro Nakanishi Minoru Miyatake Naoto Tsutsumi 《Optical Review》2004,11(6):370-377
We demonstrated that the anisotropic scattering polarizer (ASP) laminated to a glass substrate surface increased the optical efficiency of an organic electroluminescent (EL) device for liquid crystal display (LCD) backlight applications. ASP was prepared by drawing the liquid crystal polymer (LCP) dispersed poly(carbonate) film and extracted the emitting light trapped in the substrate of an organic EL device involved in polarization selectivity. Light extraction ability and polarization selectivity were changed by thickness of the electron transporting layer (ETL) of the organic EL device. Optical efficiency of a 60 nm thick ETL device through absorbing polarizer was not much improved by the lamination of ASP, whereas low efficiency of a 120 nm thick ETL device was greatly improved by this lamination due to extraction of the waveguided light as a substantially polarized emission. Although the degree of increase for the 120 nm thick ETL device was very large, the final optical efficiency was less than or only comparable to that of the thinner device. In 90 nm thick ETL device, however, the lamination of ASP increased the optical efficiency by a factor of 1.2–1.3 against a 60 nm thick ETL device. © 2004 The Optical Society of Japan 相似文献
874.
Craig A. Parish Jian-Guo Dong William G. Bornmann Joan Chang Koji Nakanishi Nina Berova 《Tetrahedron》1998,54(52):2717-15758
The analysis of a series of seventeen vinblastine analogs by circular dichroism is described. Exciton coupling of the indole and indoline chromophores of these compounds provides a general, non-empirical method for the assignment of the C16′ configuration with the bioactive C16′-S and the inactive C16′-R analogs giving rise, respectively, to positive and negative couplets. An analysis of the non-coupled transitions of the CDs indicates that a positive Cotton effect at 305 nm, although empirical, is associated with bioactivity. Theoretical calculations of the UV and CD spectra of vinblastine diastereomers are also described. 相似文献
875.
In many real-world oscillator systems, the phase response curves are highly heterogeneous. However, the dynamics of heterogeneous oscillator networks has not been seriously addressed. We propose a theoretical framework to analyze such a system by dealing explicitly with the heterogeneous phase response curves. We develop a method to solve the self-consistent equations for order parameters by using formal complex-valued phase variables, and apply our theory to networks of in vitro cortical neurons. We find a novel state transition that is not observed in previous oscillator network models. 相似文献
876.
877.
The macropore structure evolution of a silica monolith during the formation process was observed by laser scanning confocal microscopy (LSCM) for two kinds of systems. The obtained LSCM images were further subjected to image analysis, and the geometrical parameters were calculated. On the basis of the parameters obtained, improved compositions for high efficiency preparation of macroporous monoliths are discussed. 相似文献
878.
Ochiai M Kaneaki T Tada N Miyamoto K Chuman H Shiro M Hayashi S Nakanishi W 《Journal of the American Chemical Society》2007,129(43):12938-12939
879.
Munaka T Abe H Kanai M Sakamoto T Nakanishi H Shoji S Kimura S Maekawa T Murakami A 《The Analyst》2007,132(6):512-514
This paper describes the cultivation of primary cells in a microchamber and the real-time monitoring of small amounts of antibody secretion after the introduction of a minute amount of stimulus by a microinjector using time-resolved fluorescence anisotropy analysis. 相似文献
880.
Nakanishi T Inatomi Y Murata H Ishida SS Fujino Y Miura K Yasuno Y Inada A Lang FA Murata J 《Chemical & pharmaceutical bulletin》2007,55(2):334-336
A new ursane-type triterpene, named as cheiranthic acid (1), was isolated from the MeOH extract of whole plants of Oenothera cheiranthifolia (Onagraceae) along with an isomeric pair of known oleanane- and ursane-type triterpenes (arjunolic acid and asiatic acid) and three flavonol glucuronide analogues (quercetin 3-O-glucuronide, its n-butyl ester, and myricetin 3-O-glucuronide). Their structures were elucidated based on spectroscopic evidence. 相似文献