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91.
We have synthesized AlN nanoparticles (NPs) doped in-situ with Er (AlN:Er) using inert gas condensation technique. Using x-ray diffraction (XRD) peak broadening analysis with the Williamson–Hall (W–H) Uniform Deformation Model (UDM) the crystallite size of the NPs and the strain in NPs were found to be 80±38 nm and 3.07×10−3±0.9×10−3 respectively. In comparison, using the Debye–Scherrer's (DS) formula, we have inferred that the crystallite size of the NPs was 23±6 nm and the average strain was 4.3×10−3±0.4×10−3. The scanning electron microscopy images show that the NPs are spherical and have an average diameter of ∼300 nm. The crystallite size is smaller than the size of the NPs revealing their polycrystalline behavior. In addition, the NPs strain, stress and energy density were also calculated using W–H analysis combined with the Uniform Deformation Stress Model (UDSM) and the Uniform Deformation Energy Density Model (UDEDM). Suggested by the spherical geometry and polycrystalline nature of the AlN NPs, the strain computed from UDM, UDSM and UDEDM were in agreement confirming an isotropic mechanical nature of the particle. Luminescence measurements revealed the temperature dependence of the optical emission of the Er3+ ions, confirming the use of AlN:Er NPs for nano-scale temperature sensing.  相似文献   
92.
We evaluate the spin polarization (Edelstein or inverse spin galvanic effect) and the spin Hall current induced by an applied electric field by including the weak localization corrections for a two-dimensional electron gas. We show that the weak localization effects yield logarithmic corrections to both the spin polarization conductivity relating the spin polarization and the electric field and to the spin Hall angle relating the spin and charge currents. The renormalization of both the spin polarization conductivity and the spin Hall angle combine to produce a zero correction to the total spin Hall conductivity as required by an exact identity. Suggestions for the experimental observation of the effect are given.  相似文献   
93.
Ab initio calculations show that the coupling between antiferrodistortive (AFD) distortions and magnetization in perovskite Bi2FeMnO6 is prohibited to make magnetization rotate as effective Hubbard parameter is larger than 2.7 eV, where anomalies in antiferromagnetic (AFM) vectors and band gap varying with on-site Coulomb interaction can be observed. This coupling is attributed to the antisymmetric Dzyaloshinskii-Moriya interaction driven by the eg-eg states AFM interaction and charge redistribution with respect to different AFD distortions.  相似文献   
94.
X-ray powder diffraction and magnetization measurements have been carried out on Rh2Mn1+xSn1−x (0≤x≤0.3) alloys. The alloys, which crystallize in the L21 structure, were found to exhibit ferromagnetic behavior. The lattice constant a at room temperature decreases with increasing x, whereas the Curie temperature TC decreases linearly. At 5 K the magnetic moment per formula unit first increases with increasing x and then saturates for x≥0.2. The experimental results are discussed in terms of the influence of the Mn-Mn exchange interactions between the Mn atoms on the Sn and Mn sites.  相似文献   
95.
We extend the method of searching “eigen-operator” of the square of the Schroedinger operator to the interaction picture, which not only helps to construct Hamiltonians of two kinds of parametric amplifiers but also leads to a new uncertainty relation regarding to the free Hamiltonian and the interacting Hamiltonian.  相似文献   
96.
基于滑移网格与RNG湍流模型计算泵内的动静干扰   总被引:16,自引:0,他引:16  
本文利用三维Navier-Stockes方程和RNG湍流模型,在转动与静止部件间采用滑移网格技术建立交互界面,对泵内动静干扰引起的三维非定常湍流进行了计算,得到了旋转叶轮与固定导叶间流体的湍流特征。从计算结果可知,静叶与动叶间各点的压力脉动频率成分一致,且幅值沿周向呈正弦变化规律。这说明利用滑移网格技术及RNG湍流模型,可以模拟三维非定常动静干扰流动问题。  相似文献   
97.
张翼  李玉同  张杰  陈正林  R.Kodama 《物理学报》2005,54(10):4799-4802
对超强激光与等离子体相互作用过程中发生的氘-氘反应的中子能谱进行了计算.并将计算结 果与实验结果相比较.采用麦克斯韦能量分布和高斯形式的角分布对实验结果进行拟合,从 而确定了入射氘离子的温度和角分布,为研究离子的加速机制提供了依据. 关键词: 中子能谱 激光与等离子体相互作用  相似文献   
98.
In this work,the KLL dielectronic recombination (DR) processes of highly charged He-like to O-like xenon ions are studied systematically by using a DR program,which is based on the multi-configuration Dirac-Fock (MCDF) method.The KLL DR resonant energies and the corresponding resonant strengths are calculated,emphasizing especially the effect of the Breit interaction on the DR strengths.The theoretical KLL DR spectra are obtained and compared with the latest experimental results obtained in the Shanghai Electron Beam Ion Trap.  相似文献   
99.
通过求解N巴黎光学势的复薛定谔方程,研究了N系统的近阈束缚和共振行为,得到了一个p系统的13P0共振态.发现其能量和宽度与最近BES用Breit Wigner(B W)公式分析J/ψ→γp衰变的实验数据给出的结果相容.讨论了这一结果的含义及进一步研究的建议.  相似文献   
100.
The main aim of the present work was to prepare TPGS stabilized D-α-Tocopherol, lemon oil, tween-80, and water nanoemulsion by low cost and highly effective sonication method. The prepared nanoemulsion showed good stability for 60 days at variable temperature conditions i.e. 4, 25 and 37 °C. The tolerance of the prepared nanoemulsion to salt (50 mM–500 mM) and pH (pH 2–pH 7.4) was also studied. The morphology and droplet size of pure and quinine loaded nanoemulsion was characterized with transmission electron microscopy. The prepared formulation was transparent and the obtained average particle size ranged between 25 nm and 35 nm. The nanoemulsion was found to be non toxic. The cell viability study of pure nanoemulsion carried out on Hep G2 cells revealed that the cell viability was 100%. The formulation further exhibited high quinine loading and release capacity with cumulative release up to 76 ± 2% and 65 ± 2% at pH 7.4 and pH 5.5 respectively. The interaction between quinine and vitamins (riboflavin, thiamine and biotin) was also carried out (aqueous medium). The study revealed that riboflavin had strong interaction with quinine and vitamins vis-à-vis thiamine and biotin.  相似文献   
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