新型红色发光材料La3PO7:Eu3+的合成及发光性质研究

用固相法合成了La3PO7:Eu3+,用X射线衍射仪测定了其晶体结构,室温下用Hitachi F-4500测定了其光致发光性质.结果表明合成的La3PO7:Eu3+属单斜相结构,Eu3+在单斜结构的La3PO7基质中占据非对称性格位.在254 nm光激发下,La3PO7:Eu3+发射出较强的红光,表明Eu3+的5D0→7F2跃迁强度远大于5D0→7F1的跃迁强度,其色坐标和Y2O3:Eu3+的色坐标位置相近.另外,还研究了Eu3+在体相La3PO7材料中的猝灭浓度,发现当掺杂Eu3+浓度增大到7.6 mol%时,出现浓度猝灭.     

脉冲放电等离子体烟气脱硫脱硝工业试验

脉冲放电等离子体烟气治理技术具有流程简单，一次投资成本低，无二次污染，可同时脱硫脱硝，形成的副产物可回收利用等特点。     

An Economical Magnetocardiogram System Based on High-To SQUIDs

An economical magnetocardiogram （MCG） system is built in our laboratory. It mainly consists of a MCG data acquisition stage equipped with two high-To superconducting quantum interference device （SQUID） magnetometers, a data processing stage with digital filtering and a one-layer μ-metal magnetically shielded room in conjunction with a high-Tc SQUID based active compensation. Experimental results show that a noise level of pico-tesla in MCG profiles, which is necessary for clinical applications, may be achieved with the system. Moreover, stable and convenient operations of the system are demonstrated with simulating MCG measurements.     

Design of Two-Dimensional Photonic Crystal Edge Emitting Laser for Photonic Integrated Circuits

An edge emitting laser based on two-dimensional photonic crystal slabs is proposed. The device consists of a square lattice microcavity, which is composed of two structures with the same period but different radius of air-holes, and a waveguide. In the cavity, laser resonance in the inner structure benefits from not only the anomalous dispersion characteristic of the first band-edge at the M point in the first Brillouin-zone but also zero photon states in the outer structure. A line defect waveguide is introduced in the outer structure for extracting photons from the inner cavity. Three-dimensional finite-difference time-domain simulations apparently show the in-plane laser output from the waveguide. The microcavity has an effective mode volume of about 3.2（λ/nslab）^3 for oscillation mode and the quality factor of the device including line defect waveguide is estimated to be as high as 1300.     

用推广的等效两体方法求解类氦离子三体问题

介绍了求解三体问题的等效两体方法,将等效两体方法推广到原子系统,利用该方法求解类氦离子的基态,与一般的单参数变分法相比得到了与实验值符合得更好的结果,进而利用双参数变分法对所得结果进行了检验。 结果表明,等效两体方法同样适用于求解原子系统中的三体问题。 An extended equivalent two body method for three body systems is introduced in this article. The method is applied to an atomic three body system. Energies and wave functions of a helium like ion are calculated,which are consistent with the experimental data much better,in contrast to the results obtained by a one parameter calculus of variations approach. Then we use a two parameter calculus of variations approach to verify the precision of the ground state energy and wave function obtained by the extended equivalent two body method. These results indicated that the extended equivalent two body method is applicable to an atomic three body problem.     

B-值双随机Dirchlet级数的收敛性

主要研究了B-值双随机Dirichlet级数在不同条件(i){Xn}服从强大数定律,且 (ii){Xn}独立不同分布,且 等条件下的收敛性,得出了收敛横坐标的简洁公式．     

一种不等带宽光学梳状滤波器

提出了一种新型—Michelson—三面镜FabryPerot型50GHz不等带宽光学梳状滤波器设计方案,分析和模拟表明:该器件将一路信道间隔为50GHz的输入信号分离成信道间隔为100GHz的奇偶两路输出信号,其中在3dB处,奇数信道带宽大于30GHz用于10Gb/s传输,偶数信道带宽大于60GHz用于40Gb/s传输对于将来的40Gb/s系统,该器件具有优势.     

A NEW NONCONFORMING MIXED FINITE ELEMENT SCHEME FOR THE STATIONARY NAVIER-STOKES EQUATIONS

In this article, a new stable nonconforming mixed finite element scheme is proposed for the stationary Navier-Stokes equations, in which a new low order CrouzeixRaviart type nonconforming rectangular element is taken for approximating space for the velocity and the piecewise constant element for the pressure. The optimal order error estimates for the approximation of both the velocity and the pressure in L2-norm are established, as well as one in broken H1-norm for the velocity. Numerical experiments are given which are consistent with our theoretical analysis.     

格雷码与六步相移编码融合的三维结构光学测量方法

编码结构光技术是一种获取复杂目标三维结构的典型测量技术,其将编码后的结构光图案投射到待测物体表面进行调制、采集,并通过解码计算三维面形数据,可见编码方法是结构光三维测量技术的核心问题。然而,通用的格雷码编码方法和六步相移编码方法都存在一定缺陷,为此,以获取物体的高精度三维点云数据为目标,提出了一种融合格雷码与六步相移的结构光技术。首先,将格雷码结构光设计为7幅黑白相间的条纹周期图像,并通过投射角度解码操作将图像划分为多个区域;然后,设计六步相移结构光为6幅具有相位差的余弦周期图像,通过相位解包裹操作将每个子区域细分到单个像素单元;最后,融合以上两种编码结构光解码值,计算图像内每个空间点的绝对相位信息。仿真实验与实际测试实验显示,与传统六幅莫尔条纹结构光技术相比,融合结构光技术计算量较小,同时也克服了单独使用格雷码或相移技术所存在的问题,能够以较高精度获取物体目标的三维结构细节,为基于结构光的双目三维扫描系统提供一定理论依据。     

指向学科大概念的高中物理U型教学策略——以“机械能守恒定律”教学为例

学科大概念向下统领学科内核心知识,向上构成学科核心素养的基本框架,指向学科结构的中心,因此它不只是一个聚合概念,也是连接学科知识与学科核心素养的工具和媒介^[1,2].以"机械能守恒定律"教学为例探讨基于大情境,促进还原与下沉,激活学科大概念;基于大问题,促进探究与整合,建构学科大概念;基于大反思,促进反思与上浮,迁移学科大概念.