工业SO2及碳黑颗粒紫外成像遥感监测技术

为了准确有效监测工业烟囱排放,基于SO2及碳黑颗粒物的光学特性,设计并研制出一套双通道紫外成像遥感监测系统.该成像系统的两个光谱通道的中心波长分别定于310 nm和330 nm,利用两个通道的光学厚度之差反演SO2浓度图像,颗粒物浓度图像由330 nm通道获取,根据浓度图像结合光流法获取烟羽运动速度,进而计算得出SO2和碳黑颗粒物的排放速率.结果表明,该工业烟囱的SO2及碳黑颗粒物排放速率分别为72.48±3.16 kg/h和6.33±1.18 kg/h.实验采用紫外相机同时对工业烟囱排放的SO2及碳黑颗粒物进行监测,实验表明双通道紫外成像遥感监测兼具高时间分辨率与高空间分辨率,测量结果准确直观,在工业废气污染、船舶尾气污染以及火山喷发污染排放遥感监测中具有非常明显的技术优势及巨大的应用前景.     

乙基苯胺的转动光谱及分子结构

本文使用傅里叶变换微波谱仪研究了乙基苯胺类物质(邻乙基苯胺，间乙基苯胺，对乙基苯胺)的分子结构. 由于此类分子含氮原子(I¹⁴N=1)，因此跃迁谱线中都呈现出核四级裂分. 通过比较实验测定得到的分子结构，可总结苯胺环上不同位置乙基的取代对氨基及分子整体结构的影响.     

LR-selHSQMBC: Simultaneous Detection and Quantification of Very Weak Long-Range Heteronuclear NMR Correlations

The optimum detection and accurate measurement of longer-range (⁴J and higher) heteronuclear NMR correlations is described. The magnitude and/or the sign of a wide range of large and small long-range couplings can be simultaneously determined for protonated and non-protonated ¹³C and ¹⁵N nuclei using the LR-selHSQMBC experiment.     

用浓度调制光谱法测量水汽辉光放电中OH和H2O的布居数变化

本文使用波长为2.8 μm的分布式反馈激光器来测量水汽辉光放电产生的物种. 使用浓度调制光谱仅观察到OH自由基和瞬态H₂O分子的吸收光谱. 吸收峰的强度和方向随解调相位而变化，但是H₂O的一个吸收峰的方向始终与其它峰相反. OH和H₂O的不同光谱取向反映了能级中粒子数量的增加或减少. 如果在放电过程中可以检测到更多的瞬态物种，则可以更好地研究H₂O的激发、电离和分解动力学. 研究表明，浓度调制光谱的解调相位关系可以用来研究分子能级的布居数变化.     

HL-2A装置中性束发射光谱 诊断系统的研制与测试

在HL-2A装置上完成了一套32通道束发射诊断系统(BES)，可对径向r=12~44cm, 极向-7.5~+7.5cm二维空间范围内的长波长()电子密度扰动信息进行测量，其时间分辨率达到0.5ms，空间分辨率1~2cm。系统由内置于真空室的非对称镜头组、传输光纤、高性能探测器模块以及辅助的冷却和真空设备构成。系统的噪声在低频时(f<100kHz)主要由散粒噪声贡献，在较高频率时由散粒噪声和e噪声共同决定。在典型的HL-2A装置放电模式中，对于200kHz以下的扰动，该系统的信噪比(SNR)均大于3。     

Intertwined Detection and Recognition Roles of Tetrazine in Synergistic Anion-π and H-bond Based Anion Receptor

The intrinsic properties of tetrazine as a π-anion receptor and as an on/off recognition probe merged with H-bond ability of an urea motif into a single architecture constitutes a new generation of well-defined anion receptors. Complexation properties directly benefit from the dual and synergistic contribution of tetrazine and urea. In this study, we report on the synthesis and assessment of binding properties to anions of diverse geometries. Association constants have been predicted by theoretical calculations and evaluated by multiple and complementary experimental techniques including electrospray-mass tandem spectroscopy, NMR, UV-visible, steady state fluorescence spectroscopies and time resolved fluorescence. These results provide the basis for a better understanding of both the complexation and the anion-dependent quenching mechanism.     

Unravelling the Role of Water in Ultrafast Excited-State Relaxation Dynamics within Nano-Architectures of Chlorophyll a

Water plays a pivotal role in structural stability of supramolecular pigment assemblies designed for natural light harvesting (for example, chlorosome antenna complex) as well as their artificial analogs. However, the dynamic role of water in the context of excite-state relaxation has not been explored till date, which we report here. Using femtosecond transient absorption spectroscopy, we investigate the excited-state dynamics of two types of nano-scale assemblies of chlorophyll a with different structural motifs, rod-shaped and micellar assemblies, that depend on the water content. We show how water participates in excess energy dissipation by vibrational cooling of the non-thermally populated Q_y band at different rates in different types of clusters but exhibits no polar solvation dynamics. For the micelles, we observe a bifurcation of stimulated emission line shape, whereas a positive-to-negative switching of differential absorption is observed for the rods; both these observations are correlated with their specific structural aspects. Density functional theory calculations reveal two possible stable ground state geometries of dimers, accounting for the bifurcation of line shape in micelles. Thus, our study elucidates water-mediated structure–function relationship within these pigment assemblies.     

第三族金属氧化物离子对二氧化碳转化的红外光谱研究

本文利用红外光解离光谱研究了第三族金属氧化物离子对二氧化碳分子的转化机制. 研究表明，对于[ScO(CO₂)_n]⁺体系，在n≤4时，形成了溶剂化结构；在n=5时，形成了碳酸盐结构，实现了二氧化碳的转化. 对于[YO(CO₂)_n]⁺体系，需要4个二氧化碳分子就可以实现二氧化碳的转化. 而在[YO(CO₂)_n]⁺体系中，只发现了溶剂化结构，没有观察到碳酸盐结构. 理论计算表明，[YO(CO₂)_n]⁺体系拥有最小的溶剂化结构向碳酸盐结构转化能垒，[LaO(CO₂)_n]⁺体系拥有最大的溶剂化结构向碳酸盐结构转化能垒. 本文从分子水平揭示了不同金属氧化物离子对二氧化碳分子转化的影响规律.     

基于斜向背散射偏振拉曼光谱的{100}c-Si面内应力分析

复杂应力状态下应力分量的解耦分析对半导体的设计和制造具有重要意义。本文开展了方法学研究,首先建立了{100}晶面族单晶硅面内应力分量解耦分析模型,基于该模型,通过改变入射光和散射光的几何构型和偏振构型,可得到单晶硅拉曼频移与应力分量的解析关系。在此基础上,提出了一种利用斜向背散射偏振拉曼光谱在不同倾角、偏振方向和样品旋转角度下开展原位拉曼探测实现应力分量解耦分析的实用技术。本文通过实验验证了该方法的可靠性和适用性。