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91.
Kumiko Hattori Tetsuya Hattori Hiroshi Watanabe 《Probability Theory and Related Fields》1994,100(1):85-116
Summary Diffusion processes on the Sierpinski gasket and theabc-gaskets are constructed as limits of random walks. In terms of the associated renormalization group, the present method uses the inverse trajectories which converge to unstable fixed points corresponding to the random walks on one-dimensional chains. In particular, non-degenerate fixed points are unnecessary for the construction. A limit theorem related to the discrete-time multi-type non-stationary branching processes is applied. 相似文献
92.
The optical model formula of Lane and Mughabghab for E1 radiative neutron capture has been applied to resonance capture in 56Fe and 90Zr. It is shown that in general the optical model predicts the contributions to the radiative widths which are correlated with the neutron widths, except for a depletion factor representing the proportion of E1 single-particle strength remaining near the neutron threshold. The degree of correlation between measured and calculated radiative widths is related to the ratio of the variances of these widths. This enables an estimate of the factor . It is shown that the theoretical value for the ratio of the radiative to neutron widths is to a good approximation independent of the imaginary part of the optical potential. The calculated radiative width is thus well defined. The results are compared with those from the valence model and from experiment. The direct background contribution is found to be negligible compared to the average compound cross section. The contribution of d-waves to the radiative capture cross section is discussed. 相似文献
93.
Atomic beam-induced fluorination of polyimide and its application to site-selective Cu metallization
Tagawa M Maeda K Kajita T Yokota K Akamatsu K Nawafune H 《Langmuir : the ACS journal of surfaces and colloids》2007,23(23):11351-11354
Metallization methods of polyimide by hyperthermal atomic oxygen and atomic fluorine beams were developed. An atomic fluorine beam with a translational energy of 6.2 eV modified the wettability of polyimide surfaces to provide an advancing water contact angle of 132 degrees. It was confirmed that in-air storage for 2 months did not alter the hydrophobic property created by the atomic fluorine beam. This stable beam-induced surface fluorination technique was then applied to site-selective electroless Cu plating on polyimide. It was demonstrated that changing the exposure sequence could create both positive- and negative-type plating processes. 相似文献
94.
Ohno H Mizutani T Kadoh Y Aso A Miyamura K Fujii N Tanaka T 《The Journal of organic chemistry》2007,72(12):4378-4389
Thermal [2 + 2] cycloaddition of allenes with an additional multiple bond is described. By simply heating the allenenes or allenynes having a three-atom tether in an appropriate solvent such as dioxane or DMF, the distal double bond of the allenic moiety regioselectively participates in the cycloaddition to form bicyclo[4.2.0]oct-5-ene derivatives in good to excellent yields. In all the reactions of allenenes, the olefin geometry was completely transferred to the cycloadducts. While the reaction of terminal allenes afforded bicyclic cyclobutane derivatives as a single isomer, the cycloaddition of some internal allenes with axial chirality yielded a diastereomeric mixture of cycloadducts. These results are in good accordance with the stepwise mechanism through a biradical intermediate with a coplanar allyl radical. 相似文献
95.
Porous Carbon Fibers Containing Pores with Sizes Controlled at the Ångstrom Level by the Cavity Size of Pillar[6]arene
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Dr. Tomoki Ogoshi Kumiko Yoshikoshi Ryuta Sueto Dr. Hirotomo Nishihara Prof. Tada‐aki Yamagishi 《Angewandte Chemie (International ed. in English)》2015,54(22):6466-6469
We report a new synthesis method of fibrous carbon material with pores sizes that are precisely controlled at the Ångstrom level, by carbonization of two dimensional (2D) porous sheets of pillar[6]arenes. The 2D porous sheets were prepared by 2D supramolecular polymerization induced by oxidation of hydroquinone units of pillar[6]arenes. Owing to the hexagonal structure of pillar[6]arene, the assembly induced by 2D supramolecular polymerization gave hexagonal 2D porous sheets, and the highly ordered structure of the 2D porous sheets formed regular fibrous structures. Then, carbonization of the 2D porous sheets afforded fibrous carbon materials with micropores. The micropore size of the fibrous porous carbon prepared from pillar[6]arene was the same size as that of the starting material pillar[6]arene assembly. 相似文献
96.
Inside Back Cover: Porous Carbon Fibers Containing Pores with Sizes Controlled at the Ångstrom Level by the Cavity Size of Pillar[6]arene (Angew. Chem. Int. Ed. 22/2015)
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97.
Rapid and sensitive method for measuring the plasma concentration of doxorubicin and its metabolites
Doxorubicin is an anti-cancer drug with a wide therapeutic range. However, it and its metabolites cause severe side effects, limiting its clinical use. Therefore, measuring the plasma concentration of doxorubicin and its metabolites is important to study the dosing regimen of doxorubicin. We developed a rapid and sensitive method by ultra-high-performance liquid chromatography with fluorescent detection for measuring the plasma concentration of doxorubicin and its metabolites in small volumes (around 10?μL), enabling repeated measurements from the same mouse. The sensitivity of 7-deoxydoxorubicinolone, a major metabolite of doxorubicin, increased about 5 times than those ever reported using conventional HPLC, and the run time was within 3?min. The area under the curve (AUC0-24?h) of doxorubicin was 5.9?μg h/mL similar to the value of 4.16?μg?h/mL obtained previously using a conventional HPLC method. This method would provide information that could be used to refine the therapeutic approach to doxorubicin use. 相似文献
98.
In terms of a Sawyer type checking condition, a necessary and sufficient condition is obtained under which the positive operator in a filtered measure space is bounded from L p (d μ) to L q (dμ) with 1 < p ≤ q < ∞. 相似文献
99.
We consider a generalization of the Stokes resolvent equation, where the constant viscosity is replaced by a general given
positive function. Such a system arises in many situations as linearized system, when the viscosity of an incompressible,
viscous fluid depends on some other quantities. We prove that an associated Stokes-like operator generates an analytic semi-group
and admits a bounded H
∞
-calculus, which implies the maximal L
q
-regularity of the corresponding parabolic evolution equation. The analysis is done for a large class of unbounded domains
with -boundary for some r > d with r ≥ q, q′. In particular, the existence of an L
q
-Helmholtz projection is assumed. 相似文献
100.
Kiyama Akihito Endo Nanami Kawamoto Sennosuke Katsuta Chihiro Oida Kumiko Tanaka Akane Tagawa Yoshiyuki 《显形杂志》2019,22(3):449-457
Journal of Visualization - Realization of a needle-free drug delivery device can solve needle-caused problems. Recently, attention has been given to the use of a focused liquid jet instead of the... 相似文献