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981.
Triptycenes carrying a leaving group at one of the bridgehead carbons afforded the title compound in good to moderate yields when irradiated with a low-pressure Hg lamp. The tropylium ion and the strong CT-complexes of the hydrocarbon were prepared. 相似文献
982.
The moiré pattern produced by two separate gratings is characterised by a fringe localisation phenomenon. A theory based on the geometric shadow of light can account for the spatial location of moiré fringes in topographical applications. The fringe location depends on the optical arrangement of the system and also on the surface slope of the specimen. Experimental results are introduced into practical usage. 相似文献
983.
Persistent polarization in poly(vinylidene fluoride) thermoelectrets prepared under high electric field has been studied by measurements of depolarization and pyroelectricity. Various polarizations are examined in detail; the polarizations related to a characteristic molecular motion near 60°C and the polarizing temperature are not responsible for the major piezoelectric effect in β-form electrets. The piezoelectricity is attributed to a polarization appearing near the melting temperature. The persistent polarization corresponding to d31 of 2 × 10?11 coul/N is about 5 × 10?6 coul/cm2. The pyroelectricity of β-form electrets is linearly correlated with the piezoelectricity. 相似文献
984.
985.
20-W ultraviolet-beam generation by fourth-harmonic generation of an all-solid-state laser 总被引:8,自引:0,他引:8
Kojima T Konno S Fujikawa S Yasui K Yoshizawa K Mori Y Sasaki T Tanaka M Okada Y 《Optics letters》2000,25(1):58-60
We have obtained UV power of 20.5 W with a repetition rate of 10 kHz by the use of a high-brightness high-power all-solid-state green laser and a high-quality CsLiB(6)O(10) crystal. This power is, to our knowledge, the highest UV power achieved so far in all-solid-state lasers. 相似文献
986.
Minami T Okamoto H Ikeda S Tanaka R Ozawa F Yoshifuji M 《Angewandte Chemie (International ed. in English)》2001,40(23):4501-4503
987.
988.
989.
The time-dependent generalized unrestricted Hartree-Fock (TDGUHF) method combined with a two-component quasi-relativistic Hamiltonian generated from the Douglas-Kroll-Hess (DKH) transformation was developed to calculate frequency-dependent molecular magnetizabilities, which are the linear response quantity of a molecule to an external magnetic field. By calculating the magnetizabilities of H(2)X (X = O, S, Se, and Te), the noble gases (He, Ne, Ar, Kr, and Xe) and small open shell molecules (CH(2), CH(3), and O(2)), we found that scalar relativistic terms affect mainly the diamagnetic magnetizability and spin-orbit (SO) interaction affects the paramagnetic magnetizability. 相似文献
990.
Ishizuka T Tobita K Yano Y Shiota Y Yoshizawa K Fukuzumi S Kojima T 《Journal of the American Chemical Society》2011,133(46):18570-18573
A heterodinuclear complex based on a Ru(II)-TPA [TPA = tris(2-pyridylmethyl)amine] complex having a peripheral Cu(II)(bpy)(2) (bpy = 2,2'-bipyridine) group bonded through an amide linkage displayed reversible intramolecular electron transfer between the Ru and Cu complex units that can be controlled by protonation and deprotonation of the bridging amide moiety. 相似文献