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991.
992.
ZnSe晶体中Cu杂质深能级的ODLTS谱 总被引:1,自引:1,他引:0
用控制Cu杂质在ZnSe品格中占据位置的方法,成功地得到了Cu-G和Cu-R中心分别占优势的ZnSe:Cu晶体.首次用ODLTS方法测得与Cu-R和Cu-G中心相应的受主能级分别位于价带顶上0.72eV和0.30eV. 相似文献
993.
We present nonlinear spectra of four-level ladder cesium atoms employing 6 S1/2→6 P3/2→7 S1/2→30 P3/2 scheme of a room temperature vapor cell.A coupling laser drives Rydberg transition,a dressing laser couples two intermediate levels,and a probe laser optically probes the nonlinear spectra via electromagnetically induced transparency(EIT).Nonlinear spectra are detected as a function of coupling laser frequency.The observed spectra exhibit an enhanced absorption(EA) signal at coupling laser resonance to Rydberg transition and enhanced transmission(ET) signals at detunings to the transition.We define the enhanced absorption(transmission) strength,HEA(HET),and distance between two ET peaks,γET,to describe the spectral feature of the four-level atoms.The enhanced absorption signal HEA is found to have a maximum value when we vary the dressing laser Rabi frequency Ωd,corresponding Rabi frequency is defined as a separatrix point,ΩdSe.The values of ΩdSe and further η=ΩdSe/Ωc are found to depend on the probe and coupling Rabi frequency but not the atomic density.Based on ΩdSe,the spectra can be separated into two regimes,weak and strong dressing ranges,Ωd≤ΩdSe and Ωd≥QdSe,respectively.The spectroscopies display different features at these two regimes.A four-level theoretical model is developed that agrees well with the experimental results in terms of the probe-beam absorption behavior of Rabi frequency-dependent dressed states. 相似文献
994.
Qiang Yuan Bing-Qiang Qiao Yi-Qing Guo Yi-Zhong Fan Xiao-Jun Bi 《Frontiers of Physics》2021,16(2):24501
Recently the AMS-02 reported the precise measurements of the energy spectra of medium-mass compositions (Neon, Magnesium, Silicon) of primary cosmic rays, which reveal different properties from those of light compositions (Helium, Carbon, Oxygen). Here we propose a nearby source scenario, together with the background source contribution, to explain the newly measured spectra of cosmic ray Ne, Mg, Si, and particularly their differences from that of He, C, O. Their differences at high energies can be naturally accounted for by the element abundance of the nearby source. Specifically, the abundance ratio of the nearby source to the background of the Ne, Mg, Si elements is lower by a factor of ∼ 1.7 than that of the He, C, O elements. Such a difference could be due to the abundance difference of the stellar evolution of the progenitor star or the acceleration process/environment, of the nearby source. This scenario can simultaneously explain the high-energy spectral softening features of cosmic ray spectra revealed recently by CREAM/NUCLEON/DAMPE, as well as the energy-dependent behaviors of the large-scale anisotropies. It is predicted that the dipole anisotropy amplitudes below PeV energies of the Ne, Mg, Si group are smaller than that of the He, C, O group, which can be tested with future measurements. 相似文献
995.
The calculation results of the R-branch transition emission spectra of(0–0) band of the A21 → X21 transition system of Sb Na molecule are presented in this paper. These R-branch high-lying transitional emission spectral lines are predicted by using the difference converging method(DCM). Our results show excellent agreement between DCM spectral lines and the experimental values, and the deviations are controlled within 0.0224 cm-1. What is more, based on the principle of over-determined linear equations, the prediction error is quantified in this work, which provides reliable theoretical support for our predicted DCM calculations. This work provides a lot of useful information for understanding the microstructure of Sb Na molecule. 相似文献
996.
Zuo Jing Zou Fan Geng Chao Li Feng Huang Guan Liu Jiaying Yang Xu Jiang Jiali Fan Zhihua Ma Xiaoyu Li Xinyang 《Journal of Russian Laser Research》2021,42(5):609-617
Journal of Russian Laser Research - The fiber laser coherent combining system with tiled aperture structure is an effective method to obtain a high-brightness laser. To realize the high-efficiency... 相似文献
997.
Hongming Zhu Xiaowen Wang Yizhi Jiang Hongfei Fan Bowen Du Qin Liu 《Entropy (Basel, Switzerland)》2021,23(5)
Instance matching is a key task in knowledge graph fusion, and it is critical to improving the efficiency of instance matching, given the increasing scale of knowledge graphs. Blocking algorithms selecting candidate instance pairs for comparison is one of the effective methods to achieve the goal. In this paper, we propose a novel blocking algorithm named MultiObJ, which constructs indexes for instances based on the Ordered Joint of Multiple Objects’ features to limit the number of candidate instance pairs. Based on MultiObJ, we further propose a distributed framework named Follow-the-Regular-Leader Instance Matching (FTRLIM), which matches instances between large-scale knowledge graphs with approximately linear time complexity. FTRLIM has participated in OAEI 2019 and achieved the best matching quality with significantly efficiency. In this research, we construct three data collections based on a real-world large-scale knowledge graph. Experiment results on the constructed data collections and two real-world datasets indicate that MultiObJ and FTRLIM outperform other state-of-the-art methods. 相似文献
998.
Jiangkuan Xing Kun Luo Haiou Wang Tai Jin Ruipeng Cai Jianren Fan 《Proceedings of the Combustion Institute》2021,38(3):4005-4012
Biomass co-firing within the existing pulverized coal boiler is thought as a practical near-term way of biomass utilization, while its detailed combustion characteristics and pollutant formation have not yet been fully understood. In the present study, we report a Carrier-phase Direct Numerical Simulation study coupled with detailed mechanism to provide a deep insight into the coal/biomass co-firing (CBCF) jet flames under different blending ratios. It is found that compared with the pure coal flame, the CBCF could (i) prompt the volatiles ignition, produce higher H2O and similar CO2 mass fractions at blending ratios of 20% and 40%, and obviously reduce the gas temperature and CO2 mass fraction at the blending ratio of 50%; (ii) prompt the coal devolatilization and char burnout at blending ratios of 20% and 40%, while the char burnout is reduced when blending ratio is 50% due to the local enrichment of large particles and lack of oxygen; (iii) reduce the thermal, prompt, NNH and N2O-intermediate routes of NO formation, but show limited effect on the NO-reburning route of NO destruction, therefore, resulting in an obvious NO reduction. 相似文献
999.
Yong Fan Junqi Guo Minhyeok Lee Norihiko Iki Yuji Suzuki 《Proceedings of the Combustion Institute》2021,38(2):2361-2370
A premixed H2/air flame with N2 dilution (Uin = 533 cm/s, ? = 1) was formed in a quartz micro flow reactor with/without a 100-nm thick Inconel coating for the investigation of wall chemical effect of the metal surface. Two-dimensional distributions of OH radical, O atom and H atom in the hydrogen flame were measured via the planar laser induced fluorescence (PLIF) and two-photon absorption laser induced fluorescence (TALIF), respectively. It is found that the distributions of all these three main species in the hydrogen flame are significantly affected by the wall chemical effect. OH, O and H shift downstream in the Inconel-coated channel, and also their concentration becomes lower than those in the less-reactive quartz channel. Based on the measured distributions of OH, O and H over the Inconel surface, the initial sticking coefficients (S0) of the radical quenching model are optimized. It is found that S0 for Inconel are 0.4–0.5, 0.1–0.2 and < 0.05 for OH, O and H, respectively, showing different sticking coefficients for different species for the first time. 相似文献
1000.
Qing-Yang Fan Nan Wu Shuai-Ming Chen Li Jiang Wei Zhang Xin-Hai Yu Si-Ning Yun 《理论物理通讯》2021,73(12):125701
A new boron nitride polymorph, P213 BN (space group: P213), is investigated by first-principles calculations, including its structural properties, stability, elastic properties, anisotropy and electronic properties. It is found that the new boron nitride polymorph P213 BN is mechanically, dynamically and thermodynamically stable. The bulk modulus (B), shear modulus (G) and Young's modulus of P213 BN are 91 GPa, 41 GPa and 107 GPa, respectively, all of which are larger than that of Y carbon and TY carbon. By comparing with c-BN, the Young's modulus, shear modulus and Poisson's ratio of P213 BN show tiny anisotropy in the (001), (010), (100) and (111) planes. At the same time, in contrast with most boron nitride polymorphs, P213 BN is a semiconductor material with a smaller band gap of 1.826 eV. The Debye temperature and the anisotropic sound velocities of P213 BN are also investigated in this work. 相似文献