Study of the structural relaxation and crystallization in amorphous Fe80P20 alloy by mössbauer effect

The structural relaxation and crystallization of amorphous Fe₈₀P₂₀ alloys have been investigated by Mössbauer spectroscopy. The result indicates that the process of the crystallization of Fe₈₀P₂₀ makes slow progress and it was occur from outside into inside. The amorphous alloys may be classified into six different stages from amorphous to crystalline state during annealing.     

表面约束稳态装置中高频离子声波的激发特性

高频离子声波由于Landau阻尼很大,一般难以激发。本文研究了表面约束稳态装置上高频离子声波的激发特性。实验表明,仔细控制放电参数可以激发起纯离子声波,密度涨落n/n_o最大可以达到7.5％。     

LD side-pumped Nd:GGG CW laser operating at 1110 and 1105 nm dual wavelengths and 1110 nm single wavelength

A diode-side-pumped continuous-wave Nd:GGG laser operating at dual-wavelength (1110 and 1105 nm) and single wavelength of 1110 nm is demonstrated for the first time. The maximum output power of the 1110 and 1105 nm dual-wavelength operation is 13.2 W. By adjusting the orientation of an insertion mirror, the relative intensities of the two wavelengths can be changed. Thus single wavelength operation at 1110 nm is obtained, and the output power is 9.6 W.     

Analytical vectorial structure of Hermite-cosine-Gaussian beam in the far field

Based on the vector angular spectrum representation of electromagnetic beams and the method of stationary phase, the vectorial structure of a Hermite-cosine-Gaussian (HcosG) beam in the far field is derived in analytical form. Energy flux distributions for the TE term, TM term and the whole beam are represented. The vectorial structures of HcosG beams with different Hermite models are depicted. The effects of cosine displacement parameters on the vectorial structure are also demonstrated. The results may provide a flexible approach to manipulate HcosG beams in free space.     

Electrochemical performance of a nonaqueous rechargeable lithium-air battery

Nonaqueous rechargeable lithium-air battery has so high specific capacity and specific energy that it is being widely researched by academia, corporation, and different research institutes. When used in dried air and absorbing oxygen form the air, this battery is called lithium-air battery, and its specific capacity based on cathode active material (oxygen) is infinite. However, its cycle performance is very limited as reported by the state-of-the-art researches. This cycle problem is mainly caused by instability of electrolyte. Based on electroanalysis of materials’ electrochemical property, a stable electrolyte solvent (sulfolane) and a lithium salt LiBF₄ are selected as electrolytes in this work. Coupled with other eligible battery materials and careful assembly, the lithium-air battery exhibits favorable cycle performance. Above all, this lithium-air system is evaluated objectively in this paper.     

Quantum State Sharing of an Arbitrary Three-Atom State by Using Five-Atom Cluster State in Cavity QED

We present a scheme for implementing the deterministic quantum state sharing of an arbitrary three-atom state by using a five-atom cluster state and a Bell-state in cavity QED. In the scheme, it does not involve Bell-state measurement and only needs to perform the single-atom measurements. Our scheme is not sensitive to both the cavity decay and the atom radiation, which is of importance in view of decoherence.     

水稻秸秆接力处理过程中的红外光谱研究

作物秸秆就地焚烧已经和正在引起严重的大气污染,土壤微生物对作物秸秆的较难分解是作物秸秆农业利用的主要限制因子之一。文章采用傅里叶红外光谱(FTIR)分析技术对水稻秸秆接力处理(化学水解—微生物培养)过程进行了研究,分析探讨了接力处理的化学机理。由红外光谱的分析可见,经过接力处理,水稻秸秆半纤维素和纤维素大大降低,C／N比也降低到适合微生物生长的范围,硅元素的含量也降低,水溶性的物质含量升高,其结果与化学分析的结果一致。文章提出的水稻秸秆接力处理方法能为作物秸秆的农业利用提供有效途径。     

光纤压力传感器物理实验仪的研制

给出一个应用于光纤压力传感器物理实验仪的设计实例。给出了实际应用的框图,可使我们对光纤及传感器有所了解。     

Femtosecond laser-induced ZnSe nanowires on the surface of a ZnSe wafer in water

We present a simple route for ZnSe nanowire growth in the ablation crater on a ZnSe crystal surface. The crystal wafer, which was horizontally dipped in pure water, was irradiated by femtosecond laser pulses. No furnace, vacuum chamber or any metal catalyst were used in this experiment. The size of the nanowires is about 1-3 μm long and 50-150 nm in diameter. The growth rate is 1-3 μm/s, which is much higher than that achieved with molecular-beam epitaxy and chemical vapor deposition methods. Our discovery reveals a rapid and simple way to grow nanowires on designed micro-patterns, which may have potential applications in microscopic optoelectronics.     

Exact solutions and symmetry analysis for the limiting probability distribution of quantum walks

In the literature, there are numerous studies of one-dimensional discrete-time quantum walks (DTQWs) using a moving shift operator. However, there is no exact solution for the limiting probability distributions of DTQWs on cycles using a general coin or swapping shift operator. In this paper, we derive exact solutions for the limiting probability distribution of quantum walks using a general coin and swapping shift operator on cycles for the first time. Based on the exact solutions, we show how to generate symmetric quantum walks and determine the condition under which a symmetric quantum walk appears. Our results suggest that choosing various coin and initial state parameters can achieve a symmetric quantum walk. By defining a quantity to measure the variation of symmetry, deviation and mixing time of symmetric quantum walks are also investigated.