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991.
Photo‐induced degradation of a monolayer of the Ru(II) complex adsorbed on anatase TiO2 thin films was studied by using resonant micro‐Raman spectroscopy. We developed two contrastive experiments to analyze the degradation mechanism. An exponential decay law was found when the dye was irradiated in the absence of a reducing agent. While the sensitized TiO2 thin film electrode was covered by the I–/I3– redox couple, the dye degradation exhibited a slowed linear decay. The experimental result was compared and the degradation mechanism was analyzed. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
992.
应用键轨道连接矩阵方法提取结构参数PX1CC和PX1CH, 并用于建立预测烷烃折光率的QSPR模型.该模型不仅预测精度较高(其误差仅为0.0048),而且模型中采用的参数表达了直接与分子的折光能力相关的结构信息(即烷烃分子中电子被极化的能力).此参数提取简单,既具备拓扑指数简单、易算,物理意义明确. 相似文献
993.
Magnetic powders for sintered NdFeB magnets have been prepared by using an advanced processing method including strip casting, hydrogen decrepitation, jet milling and rubber isotropic press. The effects of Dy, Ga and Co addition on the microstructure and magnetic properties of sintered magnets have been investigated. By adopting a suitable component ratio and adjusting proper technological parameters, we have prepared high-coercivity sintered NdFeB magnets with hard magnetic properties of jHc=25.6 kOe, Br=13.2 kG and (BH)max=39.9 MGOe. The temperature coefficient of coercivity of the magnets (between 20 and 150 °C) is –0.53%/°C. The magnetic properties at high temperature satisfy the needs of permanent magnet motors. 相似文献
994.
995.
Samples La1−aAgaMnO3 (0.05?a?0.50) were sol–gel fabricated. A part of Ag was found to dissociate and run off the samples in sintering process when sintering temperature exceeds 700 °C, resulting in a composite of La1−xAgxMnO3 and MnO2/Mn2O3. The magnetic and transport properties of the composite have been studied. The sample with the nominal composition La0.7Ag0.3MnO3 was found to show the greatest magnetoresistance in the sample group. Detailed analysis on average Mn valence reveals a composite of (La0.985Ag0.015MnO3)0.776[(MnO2)0.590(Mn2O3)0.410]0.224. Its MR ratio at room temperature exceeds 24% under a field of 1.8 T. A conductivity leap has been observed around a=0.30. It suggests a kind of field-induced fluctuation in percolation in the samples investigated. 相似文献
996.
L. Gao 《Surface science》2007,601(15):3179-3185
We report on the structural evolution at the initial growth stage of perylene thin films on Au(1 1 1) surface. Scanning tunneling microscopy and spectroscopy have been employed to investigate the structural and electronic properties at 78 K. Rapid molecular diffusion was observed at low submonolayer coverage. Molecules form an ordered structure at monolayer coverage. For the second layer, impinging molecules nucleate into molecular islands with an ordered intermediate structure. 相似文献
997.
The crystal structure, electronic structure and hydrogen site occupancy of LaNi4.5Al0.5Hy intermediate phase (y=2.0, 3.0, 4.0) have been investigated using the full-potential linearized augmented plane wave (FLAPW) method. For the first time we analyzed the interstitial site occupation of hydrogen atoms. The H atoms were found to prefer the 6m, 3f and 12n sites, while no 4h sites were occupied. A narrowed Ni-d band is found due to the lattice expansion: the total DOS at EF increases with y, which indicates that the compounds become less stable. The interaction between Al and Ni, with H plays a dominant role in the stability of LaNi4.5Al0.5Hy intermediate phase. The smaller the shift of EF towards the higher energy region, the more stable the compounds will be. Our results are compared with experimental data and discussed in the light of previous works. 相似文献
998.
Density functional theory study on LaNi4.5Al0.5 hydride phase: electronic properties and sites occupation* 下载免费PDF全文
In this paper the crystal structure, electronic structure and hydrogen site occupation of LaNi4.5Al0.5Hy hydride phase (y = 5.0, 6.0) have been investigated by using full-potential linearized augmented plane wave method. The hydrogen atoms were found to prefer the 6m, 12o and 12n sites, while no 4h sites were occupied. A narrowed Ni-d band is found due to the lattice expansion, the total density of states at EF increases with y, which indicates that the compounds become less stable. The interaction between Al and Ni, H plays a dominant role in the stability of LaNi4.5Al0.5 hydride phase. The smaller the shift of EF towards the higher energy region, the more stable the compounds will be. The obtained results are compared with experimental data and discussed in the light of previous works. 相似文献
999.
A controlled quantum teleportation scheme of an N-particle unknown state via three-particle W1 states 下载免费PDF全文
In this paper a controlled quantum teleportation scheme of an N-particle unknown state is proposed when N groups of three-particle W1 states are utilized as quantum channels. The quantum information of N-particle unknown state is transmitted from the sender to the recipient under the control of all supervisors. It can be realized with a certain probability. After the sender makes Bell-state measurements and the supervisors perform the computational basis measurements, the recipient will introduce auxiliary particles and carry out unitary transformations depending on classical information from the sender and the supervisors. Finally, the computational basis measurement will be performed by the recipient to confirm whether the teleportation succeeds or not. The successful completion of the scheme relies on all supervisors' cooperation. In addition, the fidelity and security of the scheme are discussed. 相似文献
1000.
Multiple ionization of argon accompanied by electron loss and capture of 0.22-6.35 MeV C^q+ ions 下载免费PDF全文
In this paper a projectile ions recoil ions coincidence technique is employed to investigate the target ionization and projectile charge state changing processes in the collision of 0.22-6.35 MeV Cq^+ (q = 1 - 4) ions with argon atoms. The partial cross section ratios of the double, triple, quadruplicate ionization to the single ionization (or the single capture) of argon associated with single electron loss (or single electron capture) by the projectile are measured and compared with the previous experimental results. In the present experiment, it is observed that the ratios of ionization cross sections R associated with single loss and single capture depend strongly on the projectile charge state and vary significantly with different reaction channels as impact energy increases. In addition, this paper gets empirical scaling laws for the ionization cross section ratios R corresponding to the projectile single loss and finds that the ratios of the double ionization to the single ionization associated with single electron capture remain constant in the present energy range. 相似文献