An endohedral fullerene-based nuclear spin quantum computer

We propose a new scalable quantum computer architecture based on endohedral fullerene molecules. Qubits are encoded in the nuclear spins of the endohedral atoms, which posses even longer coherence times than the electron spins which are used as the qubits in previous proposals. To address the individual qubits, we use the hyperfine interaction, which distinguishes two modes (active and passive) of the nuclear spin. Two-qubit quantum gates are effectively implemented by employing the electronic dipolar interaction between adjacent molecules. The electron spins also assist in the qubit initialization and readout. Our architecture should be significantly easier to implement than earlier proposals for spin-based quantum computers, such as the concept of Kane [B.E. Kane, Nature 393 (1998) 133].     

工业园区边界污染气体定量分析及来源研究

工业园区中边界污染气体的浓度不仅受工业园区无组织污染源的排放影响，也受园区道路机动车尾气的扩散影响。利用AG-FTIR-DA3000型开放光程傅里叶变换红外光谱（Open-FTIR）测量系统，对厂区边界污染气体进行实时在线测量，确定污染气体厂界实测浓度。同时，针对机动车尾气扩散影响厂区边界污染气体浓度的问题，通过AG-FTIR-DX4000型便携式傅里叶变换红外光谱（FTIR）测量系统，确定不同排放标准下机动车尾气污染源浓度。利用便携式FTIR测量结果、风速风向、大气稳定度、车流量等变量因素建立参考坐标，给出了高斯扩散的数理模型。并结合Open-FTIR，对Open-FTIR的测量路径进行积分计算并构建点线源扩散模型，从而建立各种排放标准的烟团线源扩散表。将Open-FTIR实测浓度与构建的点线源扩散模型模拟浓度相结合，分析工业园区边界污染气体的来源。结果表明：厂区边界污染气体主要包括一氧化碳、甲烷、乙烯、乙醛、丙烯、甲醇、丙醛、异丁烯、甲醛、二氧化硫，其中一氧化碳、甲烷、乙烯浓度受机动车尾气的扩散影响。早晚高峰期时，机动车尾气的扩散对边界污染气体浓度影响较大；非高峰期，在1:00时与4:00—6:00时浓度骤升，出现高浓度点，不符合机动车尾气模型排放规则，主要受园区排放影响。其最高浓度与集中浓度分别为：5.50与4.00 mg·m-3；1.85与1.60 mg·m-3；78.00与40.00 μg·m-3。对比扩散表，符合尾气扩散浓度分布结果。其他测量结果组分的最高值和平均值依次为：1.65与1.40 mg·m-3；2.60与1.27 mg·m-3；43.53与11.40 mg·m-3；310.23与839.05 μg·m-3；76.32与38.96 μg·m-3；47.70与25.20 μg·m-3；1.33与1.16 mg·m-3。该研究不仅实现了工业园区边界多组分污染气体的实时在线测量，同时结合外场环境及便携式FTIR测量结果实现了边界污染气体浓度的混合测定。为今后对工业园区边界污染气体的来源判断提供了一种分析思路。     

Creation of a three-dimensional optical chain for controllable particle delivery

We propose a design for producing a conveyable quasi-periodic optical chain that can stably trap and deliver multiple individual particles in three dimensions at different planes near the focus. A diffractive optical element (DOE) is designed to spatially modulate the phase of an incoming radially polarized beam. For a tighly focused beam, a three-dimensional (3D) optical chain can be formed because of the difference in the Gouy phase shift from two concentric regions of the DOE. A desired number of particles can be stably tweezed one by one with individual 3D volumes in this trapping structure. By controlling the phase modulation of the incident beam, one can manipulate the interference pattern to accelerate and transport trapped particles along the optical axis in a prescribed way.     

复板静载弯曲挠度对爆炸焊接参数的影响

 爆炸焊接是利用炸药爆轰压力工作的固态焊接技术，广泛应用于制造层状金属复合材料。但对薄复板施焊安装过程中，薄板在自重及炸药重量作用下将发生弯曲。基于弹性力学薄板理论，得出了复板受均布载荷作用下产生的挠度及转角表达式；又通过分析爆炸焊接过程中的基、复板的运动参数，结合再入射流形成的声速限条件、流动限条件，推导出爆炸焊接时射流形成的预置角范围；最后将两者结合推导出在给定复板材料及长、宽的条件下，成功施焊所要求的复板最小厚度。     

用CARS技术确定拉曼退偏比的一种数据处理新方法

Yuika等人利用偏振CARS技术可以准确地确定分子的拉曼退偏比.其方法是，首先对不同检偏角_d所对应CARS谱峰的频率分布进行数学模拟，然后由所得系数随检偏角φ_d的变化求得使CARS信号中共振项消失的偏振角φ^０_d，最后由消失条件ρ＝-1/(tanθtanφ⁰_d)求出退偏比ρ，θ为产生CARS光的Pump光与Stokes光偏振方向的夹角.本文提出的数据处理方法，即交点法.同Yuika等人处理数据的方法相比，交点法毋需关于谱峰频率分布的知识，做法也更为简便.     

EAST装置微波反射成像系统光学性能评测

用宽为1cm的金属反射平面对EAST装置上96道(极向12道×径向8道)微波成像反射计的前端接收光路的道间距和探测光斑半径进行了测试,结果与仿真结果较为一致。用极向旋转的金属轮面作为反射面,研究了非理想光学条件下反射面旋转所引入的多普勒频移,结果与模拟值吻合。     

不同温度压力对浓度反演精度的定量分析

自研傅里叶变换红外光谱仪在龙凤山大气本底站测量CO₂,CH₄等温室气体.自研仪器的测量结果与符合世界气象组织标准的本底站仪器的测量结果进行对比,结果表明:自研仪器与本底站仪器测量的CO₂浓度值相关系数为0.9576,均方根误差为18.6015.自研仪器使用标准温度、压力下的校准光谱反演浓度,但测量气体的温度随着气温变化,导致自研仪器反演浓度有误差.基于以上分析,提取高分辨率透射分子吸收数据库参数计算吸收截面并结合仪器线形计算不同温度、压力下的校准光谱,根据不同温度、压力下的校准光谱来校准反演浓度.校准后,自研与本底站仪器测量的CO₂浓度值相关系数为0.9637,均方根误差为6.7800.自研与本底站仪器测量的CO₂浓度值相关系数提高,绝对误差减小,说明校准算法提高了测量结果的精确度.     

APT环上幂等阵的对角化

设R是一阿贝尔环(R的所有幂等元都在中心里),A是R上的一幂等阵.本文证明了以下结果：(a)A相抵于一对角阵当且仅当A相似于一对角阵;(b)若R是一APT(阿贝尔投射平凡)环,则A在相似变换之下可唯一地化为对角形diag{e₁, ..., e_n｝,这里e_i整除e_i+1;(c)R是APT环当且仅当R/I是APT环,这里I是环R的一幂零理想.由(a),还证明了分离的阿贝尔正则环是APT环.     

Derivative Form of Off-axis Aberration Correction Surface and Its Application in Solar Energy Concentration

By using the derivative method, we obtained the same result with that of the previous work of Chen et al. in 2006. Different from the integral form, the derivative form of the surface expression published in this paper is derived from differential equation and based on the theory of non-imaging focusing heliostat proposed by Chen et al. in 2001. The comparison of the derivative form of fixed aberration correction surface has been made with that of integral form surface as well as that of spherical surface in concentrating the solar ray.