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991.
992.
993.
A multi-level recording method is implemented in a photobleaching polymer using two-photon excitation under continuous wave illumination. It is experimentally shown that information encoded with ten levels of darkness can be successfully stored. This multi-level bit optical data storage method is of importance in increasing the storage density of a recording material and the speed of data access. 相似文献
994.
995.
M. Gu S. Wang J. Wu D. Feng W. Xu 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2005,34(1-3):97-100
Solid C60 was stored in NO and O2 under high pressure, and the
molecule NO and O2 were found to diffuse into the octahedral
interstitial sites in its fcc crystal lattice. Their 13C NMR MAS
spectra composed of a primary resonance at 143.7 ppm, accompanied by several
minor peaks shifted downfield respectively. The spectra at various
temperatures from 210 to 300 K have been measured, and the chemical shifts
of the minor peaks referenced to the primary resonance versus inverse
temperature show straight lines. But, the lines do not go through origin,
and their intercepts are equal to 0.13 ppm or its multiple. Due to a
non-zero intercept at high-temperature limit, we proposed that there is a
charge transfer from NO and from O2 to C60. The quantity of the
charge transferred has been calculated, that is about 0.065 qe-
(qe- for the elementary charge on an electron). 相似文献
996.
稀土元素原子发射光谱及其谱线干扰的高分辨率ICP—AES研究… 总被引:2,自引:1,他引:1
稀土元素在当今生产、生活中具有极重要的地位,由于稀土元素的原子发射光谱极为复杂,因此光谱干扰给稀土元素的原子发射光谱分析带来极大的困难。本工作利用高分辨率ICP-AES仪器详细研究了Sm基体对其他稀土元素分析线的光谱干扰,获得了大量的光谱及光谱干扰信息,为以稀土为基体的痕量稀土分析线的选择及光谱分析提供了依据。 相似文献
997.
The energy spectrum and the persistent currents are calculated for finite-width mesoscopic annular structures with radial potential barrier in the presence of a magnetic field. The introduction of the tunneling barrier leads to the creation of extra edge states around the barrier and the occurrence of oscillatory structures superimposed on the bulk Landau level plateaus in the energy spectrum. We found that the Fermi energy E F increases with the number of electrons N emerging many kinks. The single eigenstate persistent current exhibits complicated structures with vortex-like texture, “bifurcation”, and multiple “furcation” patterns as N is increased. The total currents versus N display wild fluctuations. 相似文献
998.
Four new mixed-ligand complexes of palladium (II) with L1 (N-benwyl-α-amino acid dianion) and L2 [ethyldiamine (en), 2. 2′-bipyridine (Bpy) and 1.10-phenanthroline (Phen)] were synthesized. All the complexes have been
characterized by elemental analyses, molar conductance, infrared and1H NMR spectra and thermo-gravimetric analyses. Crystal structures of [Pd(Bpy)(Bzval-N, O)] and [Pd(en)(Bzphe-N, O) ·H2O have been determined by X-ray diffraction analysis. The results indicate that in all the complexes’ ligand L1 coordinates to palladium (II) through deprotonated amide nitrogen and carboxylic oxygen, and there are some intramolecular
noncovalent interactions in the complexes.
Project supported by the Natural Science Foundation of Zhejiang Province, China. 相似文献
999.
We report on the experimental investigation carried out in the polarisation characteristics of femtosecond pulsed and continuous wave beams propagating through a 1×2 fibre coupler. It is demonstrated that the polarisation states of pulsed and continuous wave illumination over the broad wavelength range can be preserved in a conventional fused fibre coupler. Furthermore, the fibre coupler acts as a low-pass spectral filter in the visible wavelength range with a splitting ratio between 99.6/0.4 and 99.7/0.3. The result is of importance for fibre-optic second harmonic generation microscopy which requires the polarisation preservation to extract molecular organization of a sample. 相似文献
1000.
For a nematic polymethacrylate side chain liquid crystalline polymer, g 154 N 298 I (°C), the solidification-induced band texture has been observed aligned along the disclination under a polarizing optical microscope, when the specimen was quenched from 280°C to room temperature. The decoration technique of solidification-induced band texture, which is usually reported for main chain liquid crystalline polymers, was then introduced to reveal the director field pattern along a disclination for this side chain liquid crystalline polymer. It was found by infra-red dichroism measurements that the director orientation is parallel with the direction of the band. On this basis, disclinations with strength s=±1/2 and s=±1 were mapped according to the corresponding pattern of solidification-induced band texture. In addition, two types of inversion wall, loop-like and splay-type walls, were also found to be decorated by the solidification-induced band texture. 相似文献