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991.
We prove that, if a metric measure space admits a stratification so that each stratum satisfies the strong doubling condition, then the intrinsic distance induced from the Cheeger-type energy form coincides with the original distance. In other words, we can reconstruct the distance function by the Cheeger-type energy form. We also observe that this reconstruction does not work for the Korevaar-Schoen-type energy form.

  相似文献   

992.
We have synthesized novel σ–π conjugated polymers with N,N‐bis(p‐ethynylphenyl)‐N‐(p‐tolyl)amine as the π‐unit. The electroluminescent devices, with a double‐layer system composed of Alq and the present polymers as the emitting‐electron‐transporting and hole‐transporting layers respectively, emit green electroluminescence with a maximum intensity of 760 cd m?2. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
993.
White-light interference has changes in fringe contrast. When phase-shift techniques are applied to white-light interference, the phase-shift algorithm which can extract the phase accurately under the contrast changes is required. There is often another requirement that the phase shift between frames should not be restricted to π/2. Computer simulations show that the well-known algorithms have non-negligible errors under both requirements. To find an algorithm which will satisfy the requirements, I extract individual terms (I j I k ) in an algorithmic equation by considering symmetry of light intensity against phase, where I j is light intensity just after the j-th phase shift. Using computer simulations, I search for appropriate coefficients by which the terms are multiplied in the equation, finally finding an algorithm which satisfies both the requirements with the phase shift used.  相似文献   
994.
995.
Effect of * P--O orbital of C-apical O-equatorial (O-cis) spirophosphorane was investigated both experimentally and theoretically. O-cis phosphoranes revealed to be much more electrophilic on the phosphorus atom than O-trans isomers by experimental studies. Theoretically, the energy of the * P--O orbital of O-cis phosphorane was calculated to be lower than that of the * P--C orbital of O-trans phosphorane by 18.7 kcal/mol, and the result supports the enhanced electrophilicity of O-cis spirophosphoranes compared with O-trans isomer.  相似文献   
996.
997.
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   
998.
We investigate the long-time dynamics of two-component dilute gas Bose–Einstein condensates with relatively different two-body interactions and Josephson couplings between the two components. Although in certain parameter regimes the quantum state of the system is known to evolve into macroscopic superposition, i.e., Schrödinger cat state, of two states with relative atom number differences between the two components, the Schrödinger cat state is also found to repeat the collapse and revival behavior in the long-time region. The dynamical behavior of the Pegg–Barnett phase difference between the two components is shown to be closely connected with the dynamics of the relative atom number difference for different parameters. The variation in the relative magnitude between the Josephson coupling and intra- and inter-component two-body interaction difference turns out to significantly change not only the size of the Schrödinger cat state but also its collapse–revival period, i.e., the lifetime of the Schrödinger cat state.  相似文献   
999.
In this paper we construct many ruled real hypersurfaces in a nonflat quaternionic space form systematically, and in particular give an example of a homogeneous ruled real hypersurface in a quaternionic hyperbolic space. In the second half of this paper we characterize them by investigating the extrinsic shape of their geodesics. We also characterize curvature-adapted real hypersurfaces in nonflat quaternionic space forms from the same viewpoint.The first author was partially supported by Grant-in-Aid for Scientific Research (C) (No. 14540075), Ministry of Education, Science, Sports and Culture.The second author was partially supported by Grant-in-Aid for Scientific Research (C) (No. 14540080), Ministry of Education, Science, Sports and Culture.  相似文献   
1000.
A micro digital-holographic particle-tracking velocimetry (micro-DHPTV) method for high time-resolution flow field measurement in a micro-channel is developed. The system consists of an objective lens, a high-speed camera and a single high-frequency double pulsed laser. Particle positions in a three-dimensional field can be reconstructed by a computer-generated hologram. The time evolution of a three-dimensional water flow in a semicircular micro-channel of 100-μm width and 40-μm depth is obtained successfully using this micro-DHPTV system. The three-dimensional measurement volume of the system is 410 × 100 × 40 μm3 and is irradiated by one laser beam with the time resolution of 100 μs and a reputation rate of 1 kHz. Consequently, 130 velocity vectors in the semicircular micro-channel can be obtained instantaneously. A significant aspect of this method is that even though both the laser and camera are located in line and perpendicular to the flow direction, velocity vectors can be obtained by reconstructing the particle positions via the computer hologram and the semicircular cross section shape of the micro-channel can be resolved.  相似文献   
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