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21.
Undoped and doped ZnO with 1 at.% (atomic percentage) chromium (Cr) was synthesized by RF reactive co-sputtering for oxygen gas sensing applications. The prepared films showed a highly c-oriented phase with a dominant (0 0 2) peak at a Bragg angle of around 34.2°. The operating temperature of the prepared ZnO sensor was around 350 °C and shifted to around 250 °C for the doped ZnO sensor which is lower than that of previously reported work. The sensitivity of the sensor toward oxygen gas was enhanced by doping ZnO with 1 at.% Cr. Good stability and repeatability of the sensor were demonstrated when tested under different concentration of oxygen atmosphere. 相似文献
22.
We investigate generalized chaplygin gas for warm inflationary scenario in the context of locally rotationally symmetric Bianchi type I universe model.We assume two different cases of dissipative coefficient,i.e.,constant as well as function of scalar field.We construct dynamical equations as well as a relationship between scalar and radiation energy densities under slow-roll approximation.We also derive slow-roll parameters,scalar and tensor power spectra,scalar spectral index,tensor to scalar ratio for analyzing inflationary background during high dissipative regime.We also use the WMAP7 data for the discussion of our parameters. 相似文献
23.
High-resolution three-dimensional atomic microscopy via double electromagnetically induced transparency 下载免费PDF全文
Abdul Wahab 《中国物理 B》2021,30(9):94202-094202
We aim to present a new scheme for high-dimensional atomic microscopy via double electromagnetically induced transparency in a four-level tripod system. For atom–field interaction, we construct a spatially dependent field by superimposing three standing-wave fields(SWFs) in 3 D-atom localization. We achieve a high precision and high spatial resolution of an atom localization by appropriately adjusting the system variables such as field intensities and phase shifts. We also see the impact of Doppler shift and show that it dramatically deteriorates the precision of spatial information on 3 D-atom localization. We believe that our suggested scheme opens up a fascinating way to improve the atom localization that supplies some practical applications in atom nanolithography, and Bose–Einstein condensation. 相似文献
24.
报道了在兰州重离子加速器国家实验室电子回旋共振离子源原子物理实验平台上,用高电荷态40Arq+(1≤q≤12)离子作用于半导体Si固体表面时的电子发射产额实验测量.实验中,通过改变炮弹离子的电荷态和引出电压选取其不同的势能和动能,系统地研究了入射离子势能沉积和与其在固体中的电子能损对表面电子发射产额的贡献.结果表明,作为引起表面电子发射的两个主要因素,单离子的电子发射产额与炮弹离子在固体表面的势能沉积和电子能损都有近似的正比关系. 相似文献
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The positive parity states in even-even 152-166Dy are studied systematically in the framework of the interacting boson model (IBM). A cubic term, L=3, has been added to the Hamiltonian in order to produce the effect of triaxiality on the energy spectrum. The potential energy surfaces as a function of β and γ deformation parameters, for all isotopes have been produced. Energy levels and reduced electric quadrupole transition probabilities are calculated in framework of IBM with Cubic term (IBMC). All results are compared with available experimental data. It is found that these isotopes can be described by a schematic Hamiltonian in transition from U(5) (vibration) to SU(3) (rotation) dynamic symmetry. 相似文献
28.
We assume generalized ghost Pilgrim dark energy (GGPDE) model in the presence of cold dark matter in flat FRW universe. With suitable choice of interaction term between GGPDE and cold dark matter, we investigate the nature of equation of state parameter for GGPDE. Also, we investigate the natures of dynamical scalar field models (such as quintessence, tachyon, k-essence, and dilaton dark energy) and concerned potentials through the correspondence phenomenon between GGPDE and these models. 相似文献
29.
Mixtures of antidepressant amphiphilic drug imipramine hydrochloride and anionic surfactant: Micellar and thermodynamic investigation 下载免费PDF全文
Farah Khan Malik Abdul Rub Naved Azum Abdullah M. Asiri 《Journal of Physical Organic Chemistry》2018,31(6)
Aggregation as well as thermodynamic behavior of amphiphilic imipramine hydrochloride (IMH) drug (antidepressant) and anionic surfactant (sodium dodecyl sulfate [NaDS] as well as sodium dodecylbenzenesulfonate [NaDBS]) mixtures as a function of solution composition in aqueous solutions have been evaluated by conductometry method at different temperatures. Surfactant (NaDS and NaDBS) employed in the current study is anionic in nature. Various theoretical models such as Clint, Rubingh, Motomura, and Rodenas were employed to gain information regarding the type of interaction between the components in the solution mixtures. The value of micellar mole fraction evaluated by different utilized models is found to be more for IMH‐NaDBS mixtures in comparison with IMH‐NaDS mixtures, signifying that participation of NaDBS is more in mixed micelles as compared with NaDS. Owing to the different charge of employed drug and surfactant, which sources high synergistic results in the mixed system comparative to the possessions of their pure compounds, means here anionic surfactants were elected in favor of the quantitation of cationic drug. The value of interaction parameters (β) was also evaluated by employing the Rubingh's model. The values of Gibbs free energy (?G0m) for all systems attained to be negative in all studied systems showing that the systems are spontaneous in nature. 相似文献
30.
Yanxia Tang Hamid Reza Abdolmohammadi Abdul Jalil M Khalaf Ye Tian Tomasz Kapitaniak 《Pramana》2018,90(1):11
Polarisation of the particle spin can be an important problem for different plasmas. In this article, the contribution of the electron spin on the growth rate of the temperature anisotropy of electromagnetic instabilities has been investigated. Results show that polarisation of the electron spin will restrict the instability growth rate while instability can survive due to the spin-depolarised electrons even when the requested temperature anisotropy is vanished. Instability can reach the damping state exponentially due to the spin-polarised electrons while it can grow linearly due to the spin-depolarised (the semi-classical) electrons. 相似文献