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991.
992.
We examine the quantization of a harmonic oscillator with inverse square potential V(x)=(mω2/2) x2+g/x2 on the line −∞<x<∞. We find that, for 0<g<3?2/(8m), the system admits a U(2) family of inequivalent quantizations allowing for quantum tunneling through the infinite potential barrier at x=0. These are a generalization of the conventional quantization applied to the Calogero model in which no quantum tunneling is allowed. The tunneling renders the classical caustics which arise under the potential anomalous at the quantum level, leading to the possibility of copying the profile of an arbitrary state from one side x>0, say, to the other x<0.  相似文献   
993.
This communication describes the syntheses of the quasi-one-dimensional mixed-halogen-bridged Ni(III) complexes with strong electron correlation [Ni(chxn)(2)Cl(1-x)Br(x)](NO(3))(2) and the tuning of the spin density wave strengths of these compounds. If the Cl 3p and Br 4p make one band in the compounds, we should observe a single peak in the electronic spectra. As a result, we should observe the single peak from 1.45 to 2.00 eV depending on the mixing ratios of Cl and Br ions. Therefore, the Cl 3p and Br 4p make one band. Then, we have succeeded in tuning the spin density wave strengths of the Ni(III) complexes with the strong electron correlation by mixing the bridging halogen ions successively.  相似文献   
994.
Domino coupling of enones and enynes, which proceeds via the formation of three carbon-carbon bonds and the cleavage of one carbon-carbon bond, was developed using a Ni(0) and ZnCl2 system.  相似文献   
995.
28% electrical-efficiency operation of a diode-side-pumped Nd:YAG rod laser   总被引:3,自引:0,他引:3  
We propose a highly efficient quasi-cw Nd:YAG rod laser with a novel side-pumping design that uses microlens-free diode stacks. We demonstrate 320-W output power with 28% electrical-to-optical efficiency, which is, to our knowledge, the highest efficiency reported for diode-pumped solid-state lasers.  相似文献   
996.
The preparation and physical characterization are reported for a novel single-molecule magnet [Mn(12)O(12)(OAc)(12)(dpp)(4)] (dppH = diphenyl phosphate) with no coordinating water molecules. The crystal structure analysis reveals that there are four five-coordinate Mn(III) ions with Mn.H approaches. Addition of water in CD(2)Cl(2) solution was monitored by (1)H NMR, which showed that H(2)O could coordinate to a vacant site of a five-coordinate Mn(III) ion in solution. The measurements and analyses of magnetization hysteresis and ac magnetic susceptibility indicate that the title complex is a single-molecule magnet with a quantum tunneling behavior, whose ground state was tentatively assigned to S = 10 with g = 1.78 and D = -0.60 K.  相似文献   
997.
Magnetophoretic velocimetry detected the spin transition of a single Co-Fe Prussian Blue analogous micro-crystal in water induced by a single-shot pulse laser.  相似文献   
998.
999.
The magnetic field-induced migration of particles in liquids is a highly-promising technique for the micro-separation analysis of bioparticles, such as cells and large DNA. Here, new methods that make use of magnetophoresis and electromagnetophoresis to induce the migration of microparticles in liquids are briefly reviewed. Magnetic force and Lorentz force are utilized in the new methods. Some typical examples of the use of these methods are described, and the advantages of using a superconducting magnet for them are demonstrated.  相似文献   
1000.
An inner- and outer-N coordinated bis-Rh(I) metal complex was obtained from the reaction of N-confused porphyrin and [Rh(CO)2Cl]2 in CH2Cl2 and the structure was confirmed by a single crystal X-ray analysis.  相似文献   
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