Cu-MOF催化过氧化氢应用于多巴胺的检测

本文利用一种具有H_2O_2催化活性的Cu-MOF[Cu_3(BTC)_2(H_2O)_3,简称HKUST-1],构建了以邻苯二胺(OPD)为颜色指示分子的比色传感体系,实现了对H_2O_2和多巴胺(DA)的快速灵敏检测。HKUST-1起到催化H_2O_2氧化OPD的作用,反应体系能够呈现出显著的颜色变化。在优化条件下,415nm处的吸收峰强度与H_2O_2浓度呈双线性关系,线性范围分别为10~50 mmol/L和50~100 mmol/L,相对标准偏差分别为0.9947和0.9995,最低检出限为1.29mmol/L。由于DA能抑制H_2O_2氧化OPD,因此比色传感体系还可以用于快速检测DA,线性范围分别为0.25~5μmol/L和2.5~25μmol/L,相对标准偏差分别为0.9783和0.9705,最低检出限为0.262μmol/L。该项工作拓展了Cu-MOFs材料在生物分子催化和生物传感方面的应用。     

不均匀场中氢分子离子高次谐波产生的理论研究

在非Born-Oppenheimer近似下，通过求解含时薛定谔方程的方法，对氢分子离子在不均匀场中高次谐波的产生进行了理论研究.计算结果显示，同均匀场相比，电离的电子在不均匀场中加速会获得更多的能量，从而更有利于得到宽频谱.此外,通过优化不均匀场中的空间不均匀度，长量子路径被明显的抑制，最终通过叠加110阶到150阶谐波，获得一个60as的孤立阿秒脉冲.同时，通过库仑势和激光场的相互作用势以及时频分布图解释了其中的物理机制.     

初始振动态对氢分子离子电离通道的影响

通过数值求解非Born-Oppenheimer近似条件下的一维含时薛定谔方程,理论模拟了H2+在不同核初始振动态条件下(=0到=7)的库仑爆炸核初始动能释放谱。模拟结果表明：强激光场中氢分子离子的电离通道主要包括直接多光子电离、电荷共振增强电离及有中间过程的电荷共振增强电离,并且可以通过选取不同的初始振动态实现对氢分子离子电离通道的控制。     

氢分子离子在库仑爆炸中核动力学的同位素效应

在非Born-Oppenheimer近似条件下,通过数值求解一维含时薛定谔方程,理论模拟了H+2和HD+在相同激光条件、相同的核初始振动态条件下的库仑爆炸核动能释放谱.通过比较H+2和HD+库仑爆炸核动能释放谱中谱峰值位置的相对变化,研究了H+2在库仑爆炸中核动力学的同位素效应.数值结果表明:同位素效应在很大程度上依赖于分子离子核初始振动态的选取;特别当初始振动态v=5时,出现了特殊的同位素效应.     

使用多色合成激光场拓展高次谐波谱平台区域的宽度

本文提出了一种多色合成激光方案用来有效的提高高次谐波谱平台区域的宽度. 我们首先通过在800nm基本激光脉冲上添加一束或者两束控制激光脉冲在理论上得到双色以及三色合成激光场;其次,通过求解一维含时薛定谔方程,计算得到了在多色合成激光场条件下的高次谐波谱,计算结果表明,多色合成激光场方案可以有效的拓展高次谐波谱的平台区域;最后,我们结合电子的经典回碰动能分布以及时频分布,分析了在多色场条件下高次谐波谱平台区域拓宽的机理和微观机制.     

理论研究激光强度对H2+分子高次谐波产生的影响

本文通过求解非波恩-奥本海默近似条件下的一维含时薛定谔方程来研究脉冲强度对H₂⁺分子高次谐波的影响.由于干涉相消,在啁啾激光场的条件下在谐波谱中出现了干涉最小值.我们用全量子方法计算的时频分布图分析了分子高次谐波产生中的微观机制.此外,数值计算结果显示随着脉冲强度的增加电子的有质动力势随之增加,同时干涉最小值的位置移向谐波的高阶部分.     

Theoretical Investigation of Femtosecond-Resolved Photoelectron Spectrum of Na2 Molecules

Effect of laser fields on Na2 interaction potentials is studied by calculating the time-resolved photoelectron spectrum （TRPES） with the time-dependent wave-packet method. It is shown that the photoelectron spectrum at different delay times reflects the population in different electronic states. We inspect the periodicity of vibrational motion in neutral states, and map the vibrational wave-packet propagation in corresponding internuclear coordinate.     

Restraint of spatial distribution in high-order harmonic generation from a model of hydrogen molecular ion

The spatial distribution in high-order harmonic generation(HHG) is theoretically investigated by using a few-cycle laser pulse from a two-dimensional model of a hydrogen molecular ion. The spatial distribution in HHG demonstrates that the harmonic spectra are sensitive to the carrier envelope phase and the duration of the laser pulse. The HHG can be restrained by a pulse with the duration of 5 fs in the region from the 90 th to 320th order. This characteristic is illustrated by the probability density of electron wave packet distribution. The electron is mainly located near the nucleus along the positive-x direction from 3.0 o.c. to 3.2 o.c., which is an important time to generate the HHG in the plateau area. We also demonstrate the time-frequency distribution in the region of the positive-and negative-x direction to explain the physical mechanism.     

Effect of initial-state target polarization on single ionization of helium by 1-keV electron impact

We report new results of triple differential cross sections for the single ionization of helium by 1-KeV electron impact at the ejection energy of 10 eV. Investigations have been made for both the perpendicular plane and the plane perpendicular to the momentum transfer geometries. The present calculation is based on the three-Coulomb wave function. Here we have also incorporated the effect of target polarization in the initial state. A comparison is made between the present calculation with the results of other theoretical methods and a recent experiment [D黵r M, Dimopoulou C, Najjari B, Dorn A, Bartschat K, Bray I, Fursa D V, Chen Z, Madison D H and Ullrich J 2008 Phys. Rev. A 77 032717]. At an impact energy of 1 KeV, the target polarization is found to induce a substantial change of the cross section for the ionization process. We observe that the effect of target polarization plays a dominant role in deciding the shape of triple differential cross sections.     

Contributions of the Two Nuclei to the Harmonic Generation in H2＋ Molecules

The separate contributions of the two nuclei in H2＋ to the harmonic generation are investigated by numerically solving the time-dependent Schroedinger equation. The results show that the diverse electron distributions around the two nuclei under the effect of a laser field lead to different contributions of the two nuclei to the harmonic generation in different times, i.e., the contribution mainly comes from nucleus A around the （n ＋ 0.5） optical cycle while from nucleus B around the n optical cycle. By means of the time-frequency distributions and the coupled electron nuclear wave-packet density distributions, the physical mechanism is discussed in detail.