Raman scattering of high-temperature phase transition in KH2PO4

Raman scattering was applied to study the high-temperature phase transition (near 175°C) in KH₂PO₄. Drastic temperature-dependent changes were observed to take place in the normal modes of B₁ symmetry between 1000–3400 cm^?1. The disintegration of the dominant broad feature near 2500 cm^?1 when temperature rises beyond 150°C suggests that the alteration of the hydrogen-bond network is closely connected with this high-temperature phase transition.     

弹簧耦合摆小振动的简正模与简正频率

将耦合摆弹簧作为弹性均匀杆，导出了对称简正模与反对称简正模的本征方程，给出各角频率值的近似式，并进行了讨论。     

基于软件无线电的无源超高频RFID标签性能测试

讨论了无源超高频射频识别(UHF RFID)系统的信号传输过程及性能测试方法,以软件定义无线电方式实现了符合ISO/IEC18000-6C标准的无源标签的部分性能测试,研究了部分通信参数动态变化时标签应答功率的变化,并对不同标签的灵敏度进行了测试.所有实验在常规条件下完成,测试研究表明在基带编码采用较小的Tari值、PW为50％以及较高的调制系数时,阅读器能够接收到标签反射回来的最大功率,系统的识别距离最远. 关键词： 射频识别 无源电子标签 标签灵敏度 性能测试     

碘化铯晶体中电子型色心的电子结构研究

运用以密度泛函理论为基础的相对论性离散变分方法(DV-Xα)模拟计算了完整的和含有F心、F+心以及F2心的碘化铯(CsI)晶体的电子结构,得到了含F心和F+心以及F2心的CsI晶体电子态密度分布以及它们可能产生的光学跃迁模式.计算结果表明,含F心和F2心的CsI晶体的禁带宽度明显变窄,F心和F2心的能级都出现在禁带中并且作为施主能级位于导带底部,利用过渡态理论计算得到其能级向Cs的5d轨道发生光学跃迁,能量跃迁值分别为1.69eV和1.15eV,该结果与实验结果完全一致,F+心没有能级出现在禁带中.计算结果从理论上成功地解释了碘化铯晶体经过辐照后电子型色心所产生的吸收带起源问题.     

双色光晶格势阱中玻色-爱因斯坦凝聚体的Landau-Zener隧穿行为

考虑玻色-爱因斯坦凝聚体局限于周期性的双色光晶格势阱中,研究其中的Bloch能带结构、第一能隙和第二能隙的Landau-Zener隧穿行为.结果表明,随着双色光晶格势阱的主、次晶格相位差从0增加到π,Bloch能带中第一能隙宽度逐渐增加,而第二能隙宽度逐渐减小.同时发现,双色光晶格势阱的主、次晶格深度及其相位差对第一能隙和第二能隙的Landau-Zener隧穿性质有重要的影响.     

Left–right asymmetry for pion and kaon production in the semi-inclusive deep-inelastic scattering process

We analyze the left–right asymmetry in the semi-inclusive deep-inelastic scattering (SIDIS) process without introducing any weighting functions. With the current theoretical understanding, we find that the Sivers effect plays a key role in our analysis. We use the latest parametrization of the Sivers and fragmentation functions to reanalyze the π ^± production process and find that the results are sensitive to the parametrization. We also extend our calculation on the K ^± production, which can help us know more about the Sivers distribution of the sea quarks and the unfavored fragmentation processes. HERMES kinematics with a proton target, COMPASS kinematics with a proton, deuteron, and neutron target (the information on the neutron target can be effectively extracted from the ³He target), and JLab kinematics (both 6 GeV and 12 GeV) with a proton and neutron target are considered in our paper.     

Regularity and projective dimension of edge ideals

In this paper, we study the regularity and projective dimension of edge ideals. We provide two upper bounds for the regularity of edge ideals of vertex decomposable graphs in terms of the induced matching number and the number of cycles. Also, we generalize one of the upper bounds given by Dao and Schweig for the projective dimension of hypergraphs.     

线性等式约束下线性模型中BLU估计的稳健性

研究了线性等式约束下线性模型中BLU估计关于协方差的稳健性,得到了在协方差发生变化时,条件可估函数c′β的条件BLU估计具有稳健性的充要条件.     

基于高分辨质谱技术的婴幼儿食品中过敏原蛋白质的高灵敏检测

基于高效液相色谱-串联质谱(LC-MS/MS)技术,选择稳定性好、灵敏度高的特征肽段,利用平行反应监测(PRM)技术,实现了多类过敏原蛋白质的高灵敏度同时检测,并成功应用于婴幼儿食品中过敏原成分的分析。对于婴幼儿食品中蛋白质的提取,与传统的丙酮沉淀法比,采用膜上原位样品预处理方法(i-FASP)可实现更高的蛋白质提取效率和抗干扰能力。所检测的过敏原蛋白质的定量限(LOQ)最小可达到0.028 mg/L,其线性范围最宽可跨越4个数量级,且线性关系良好(相关系数R~2≥0.99)。该方法为食品中过敏原蛋白质组学快速分析提供了一种可靠的分析方法。