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231.
Highly efficient plastic substrate dye-sensitized solar cells using a compression method for preparation of TiO(2) photoelectrodes 总被引:2,自引:0,他引:2
Yamaguchi T Tobe N Matsumoto D Arakawa H 《Chemical communications (Cambridge, England)》2007,(45):4767-4769
The efficiency of a plastic-substrate dye-sensitized solar cell was much improved by a new method consisting of a press method without heat treatment, light confinement effect of TiO(2) film and water-based TiO(2) paste; this device shows the highest light-to-electrical energy conversion efficiency based on plastic-substrate dye-sensitized solar cells, 7.4% under 100 mW cm(-2) (1 sun) AM1.5 illumination. 相似文献
232.
The first total synthesis of the marine natural product (+)-hemifistularin 3 in enantiomerically pure form was accomplished by using the amide forming reaction of (+)-spiroisoxazoline ester with the (+)-octopamine derivative. The stereodivergent strategy employed in this effort enabled the assignment of the absolute configurations at the three stereogenic centers in (+)-hemifistularin 3. 相似文献
233.
234.
The purpose of this paper is to study the stable extendibility of the tangent bundle τn(p) over the (2n+1)-dimensional standard lens space Ln(p) for odd prime p. We investigate for which m the tangent bundle τn(p) is stably extendible to Lm(p) but is not stably extendible to Lm+1(p), where we consider m=∞ if τn(p) is stably extendible to Lk(p) for any k?n, and determine m in the case n?p−3. 相似文献
235.
Bunsow Nagasaka Hironori Omi Taro Eguchi Hirokazu Nakayama Nobuo Nakamura 《Chemical physics letters》2001,340(5-6):473-478
High-pressure 129XeNMR experiments have been performed by using a newly designed probe. 129XeNMR spectrum for the mixture of Xe and a polymer, either bisphenol-A polycarbonate or polytetrafluoroethylene, consists of two lines in a pressure range of 0.3–10 MPa. 129XeNMR chemical shift (δ) for the free Xe is mainly governed by the Xe–Xe interactions. δ for Xe confined in the micropore of polymers is strongly affected by the Xe-wall interactions. It is found that δ of the confined Xe is mainly determined by a sort of ‘virtual pressure' and is not influenced by a drastic change of the free Xe density in the critical region. 相似文献
236.
Shuyang Cao Shigehira Ozono Yukio Tamura Yaojun Ge Hironori Kikugawa 《Journal of Fluids and Structures》2010,26(5):685-702
Three-dimensional Direct Numerical Simulation (DNS) and Large Eddy Simulation (LES) are performed to investigate the shear effects on flow around a circular cylinder at Reynolds numbers of Re=60–1000. The shear parameter, β, which is based on the velocity gradient, cylinder diameter and upstream mean velocity at the center plane of the cylinder, varies from 0 to 0.30. Variations of Strouhal number, drag and lift coefficients, and unsteady wake structures with shear parameter are studied, along with their dependence on Reynolds number. The presented simulation provides detailed information for the flow field around a circular cylinder in shear flow. This study shows that the Strouhal number exhibits no significant variation with shear parameter. The stagnation point moves to the high-velocity side almost linearly with shear parameter, and this result mainly influences the aerodynamic forces acting on a circular cylinder in shear flow. Both the Reynolds number and shear parameter influence the movement of the stagnation point and separation point. Mode A wake instability is suppressed into parallel vortex shedding mode at a certain shear parameter. The lift force increases with increasing shear parameter and acts from the high-velocity side to the low-velocity side. In addition, a simple method to estimate the lift force coefficient in shear flow is provided. 相似文献
237.
Hironori Matsushima Junghwan Shin Christopher N. Bowman Charles E. Hoyle 《Journal of polymer science. Part A, Polymer chemistry》2010,48(15):3255-3264
Thiol‐isocyanate‐acrylate ternary networks were formed by the combination of thiol‐isocyanate coupling, thiol‐acrylate Michael addition, and acrylate homopolymerization. This hybrid polymerization reaction sequence was preferentially controlled by using phosphine catalyst systems in combination with photolysis. The reaction kinetics of the phosphine/acrylate thiol‐isocyanate coupling reactions were systematically investigated by evaluating model, small molecule reactions. The thiol‐isocyanate reaction was completed within 1 min while the thiol‐acrylate Michael addition reaction required ~10 min. Both thiol‐isocyanate coupling and thiol‐acrylate Michael addition reactions involving two‐step anionic processes were found to be both quantitative and efficient. However, the thiol‐isocyanate coupling reaction was much more rapid than the thiol‐acrylate Michael addition, promoting initial selectivity of the thiol‐isocyanate reaction in a medium containing thiol, isocyanate, and acrylate functional groups. Films were prepared from thiol‐isocyanate‐acrylate ternary mixtures using 2‐acryloyloxyethylisocyanate and di‐, tri‐, and tetra‐functional thiols. The sequential thiol‐isocyanate, thiol‐acrylate, and acrylate homopolymerization reactions were monitored by infrared spectroscopy during film formation, whereas thermal and mechanical properties of the films were evaluated as a function of the chemical composition following polymerization. The results indicate that the network structures and material properties are tunable over a wide range of properties (Tg ~ 14–100 °C, FWHM ~ 8–46 °C), while maintaining nearly quantitative reactions, simply by controlling the component compositions. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3255–3264, 2010 相似文献
238.
Pengfei Wang Nobuko Onozawa-Komatsuzaki Yuichiro Himeda Hideki Sugihara Hironori Arakawa Kazuyuki Kasuga 《Tetrahedron letters》2001,42(52):748-9201
Spectroscopic studies revealed that 3-(2-pyridyl)-2-pyrazoline derivatives have rather strong affinity toward divalent transition metal ions, but have almost no interaction with alkali and alkaline-earth metal ions. In the case of the 5-(4-cyanophenyl) derivative, enhancement of the fluorescence intensity was observed upon addition of the Zn2+ ion, while most of other transition metal ions caused complete quenching. 相似文献
239.
Manabu Node Kamal Kumar Kiyoharu Nishide Shin-ichi Ohsugi Tetsuo Miyamoto 《Tetrahedron letters》2001,42(52):9207-9210
Several alkanethiols and p-alkylphenylmethanethiols were synthesized, and their odors were compared with those of ethanethiol and benzyl mercaptan by human and instrumental sensors. Among the various thiols analyzed, 1-dodecanethiol (1) and p-heptylphenylmethanethiol (3) were revealed to be odorless. 1-Dodecanethiol (1) has been used instead of ethanethiol for dealkylation of ethers, and p-heptylphenylmethanethiol (3) can replace benzyl mercaptan in the preparation of a 1,3-mercapto alcohol from an ,β-unsaturated ketone. These odorless thiols will greatly improve the physical environment of the researcher working with these foul-smelling compounds. 相似文献
240.
Hironori Fujisawa 《Journal of multivariate analysis》2003,86(1):126-142
The conditional maximum likelihood estimator is suggested as an alternative to the maximum likelihood estimator and is favorable for an estimator of a dispersion parameter in the normal distribution, the inverse-Gaussian distribution, and so on. However, it is not clear whether the conditional maximum likelihood estimator is asymptotically efficient in general. Consider the case where it is asymptotically efficient and its asymptotic covariance depends only on an objective parameter in an exponential model. This remand implies that the exponential model possesses a certain parallel foliation. In this situation, this paper investigates asymptotic properties of the conditional maximum likelihood estimator and compares the conditional maximum likelihood estimator with the maximum likelihood estimator. We see that the bias of the former is more robust than that of the latter and that two estimators are very close, especially in the sense of bias-corrected version. The mean Pythagorean relation is also discussed. 相似文献