Design strategy for flat-field Schmidt optical system

The present study provides the theory base for designing flat-field Schmidt optical systems, based on the wavefront aberration of Petzval field curvature, a mathematic model of the Petzval radius is setting up. The radius of Petzval image surface is not equal to the focal length of the primary mirror or the focal length of the system. An aberration balancing method for flat-field Schmidt optical systems design is proposed: did not change parameters of the corrector, through adjusting the distance between the plate and the mirror to realize aberration equilibrium. The total physical track is more compact than equilibrium before.     

PLE spectra analysis of the sub-structure in the absorption spectra of CdSeS quantum dots

The semiconductor CdSeS quantum dots (QDs) embedded in glass are analysed by means of absorption spectra, photoluminescence (PL) spectra and photoluminescence excitation (PLE) spectra. The peaks of absorption spectra shift to lower energies with the size of QD increasing, which obviously shows a quantum-size effect. Using the PLE spectra, the physical origin of the lowest absorption peak is analysed. In PLE spectra, the lowest absorption peak can be deconvoluted into two peaks that stem from the transitions of 1S_3/2--1S_e and 2S_3/2--1S_e respectively. The measured energy difference between the two peaks is found to decrease with the size of QD increasing, which agrees well with the theoretical calculation for the two transitions. The luminescence peak of defect states is also analysed by PLE spectra. Two transitions are present in the PLE, which indicates that the transitions of 1S_3/2--1S_e and 2S_3/2--1S_e are responsible for the defect states luminescence.     

Investigation of laminar plasma remelting/cladding processing

Investigation of remelting and cladding processing with laminar plasma jets on several metals has been conducted looking for possible development of a new surface modification technique. The remelting tests illustrated that the new method could evidently improve the material microstructure and properties of cast iron. The cladding was done with Al₂O₃ ceramic powder on stainless steel. The energy dispersive spectra (EDS) analysis was used to determine the distribution of the major cladding element in the plasma-processed layers, for which the microstructure observations and hardness measurements were also performed.     

电感耦合等离子体原子发射光谱法及离子选择电极法测定荧光级氧化钇中痕量铈的研究

文章描述了荧光级氧化钇中痕量稀土铈的测定方法,在溴酸钾存在下,5摩尔/升HNO_3介质中,以P507萃取微量铈,然后有机相用硝酸、过氧化氢反萃取、再将水相浓缩定容,然后以电感耦合等离子体原子发射光谱法分析。同时用铈的离子选择电极以二次标准加入法作第二种手段分析。样品溶液以乙醇预去溶方式引入等离子体,测定下限为2微克/克,方法简单、快速、准确。离子选择电极法测定铈离子下限1×10～(-5)摩尔/升,回收率为94-101%,方法简单,结果满意、价格便宜。     

原子吸收分光光度计用于分子吸收分析测定稀土氧化物中铝和硅

用原子吸收分光光度计代替紫外－可见光度计测定元素的分子络合物的分子吸收。作为初步尝试，测定了稀土氧化物中的铝和硅，取得了满意的结果。     

Transition of Bery Phase and Pancharatnam Phase and Phase Change

Berry Phase and time-dependent Pancharatnam phase are investigated for nuclear spin polarization in a liquid by a rotation magnetic field, where two-state mixture effect is exactly included in the geometric phases. We find that when the system of nuclear spin polarization is in the unpolarized state, the transitive phenomena of both Berry phase and Pancharatnam phase are taken place. For the polarized system, in contrast, such a transition is not taken place. It is obvious that the transitions of geometric phase correspond to the phase change of physical system.     

Experimental realization of one-way quantum computing with two-photon four-qubit cluster states

We report an experimental realization of one-way quantum computing on a two-photon four-qubit cluster state. This is accomplished by developing a two-photon cluster state source entangled both in polarization and spatial modes. With this special source, we implemented a highly efficient Grover's search algorithm and high-fidelity two-qubit quantum gates. Our experiment demonstrates that such cluster states could serve as an ideal source and a building block for rapid and precise optical quantum computation.