多通道差分吸光度用于颅内血肿快速检测

近红外光密度差异法检测创伤性硬膜血肿具有快速、无创等优点,是近几年组织光学的研究热点,在急救临床上有着重要应用。为了进一步提高对颅脑外伤患者血肿程度的检测精度,采用多通道差分吸光度方法获得头部左右对称吸光度数据,即利用与近红外光源距离不同的5个检测器采集颅脑对称位置的光密度信息,计算对称位置的差分吸光度,利用偏最小二乘法建立脑部光学吸收系数与差分吸光度数据之间的校正模型,实现对颅内硬膜血肿程度的预测。可以检测具有不同头皮颅骨厚度患者是否出现硬膜血肿,也可预测脑血肿程度。模型仿真预测结果显示,所建立预测模型对硬膜血肿部分的光学吸收系数预测平均相对误差为11.16%,对血肿发生深度预测平均相对误差小于1%,基本满足创伤性硬膜血肿程度的无创检测需求。将多通道差分吸光度法引入到脑部血肿近红外光谱无创检测中来,可以明显消除个体差异对检测结果的影响,有效提高脑血肿检测精度,并能实现对患者脑血肿程度的预测,该方法为近红外光谱脑部检测研究提供了新的思路和重要参考。     

薄层色谱展开方法的几处改进

介绍了几种薄层色谱展开方法，包括中途展开、接力展开、多维接力展开、改进二维展开等，还介绍了一种简单的下行展开的操作方式以及关键部件的制作方法。     

弱(F)-反演半群上的模糊(F)-核正规系

借助于模糊(F)-核正规系刻画了弱(F)-反演半群S(P)上的强(F)-同余.证明了S(P)上的每一个模糊强(F)-同余都是由它的模糊(F)-核正规系所唯一决定的.     

基于序列运算理论的不可修复件存储决策模型

针对备件需求数量与备件库存数量的随机特性,应用序列运算理论对其供需随机过程进行动态描述.通过概率性序列的期望值理论定义了备件需求满足率,并建立了一定的备件满足率要求条件下的备件存储决策模型.     

高层间距的羟基硅铝交联蒙托土的合成与表征

采用溶胶分散法合成了一系列高层间距(2.6nm)的羟基硅铝交联蒙托土(SiAl-CLM),并用~(27)Al NMR、XRD、DTA、XPS、吡啶吸附-IR、正丁胺吸附-TPD等技术进行了表征,用脉冲反应技术考察了其催化活性。结果表明:SiAl-CLM层间存在氧化硅胶团与羟基铝聚体形成的复合Si-Al柱.SiAl-CLM的热稳定性较好,对异丙苯的裂解活性(76.8％)较高。Si的引入增加了交联蒙托土的表面酸性,尤其增加了Bronsted酸性。     

模板法合成多壁碳纳米管复合材料

以包覆在碳纳米管表面的薄层二氧化锰作为表面再包覆聚苯胺的反应性模板合成了聚苯胺和碳的复合的多壁纳米管的结构,该复合材料在水中显示出很好的分散性．该方法还可以用来合成如聚3,4-乙撑二氧噻吩、聚吡咯、二氧化硅、无定形碳等材料与碳纳米管的复合材料.     

Ultrafast Dynamics of Water Molecules Excited to Electronic F States: A Time-Resolved Photoelectron Spectroscopy Study

The ultrafast dynamics of water molecules excited to the two F states is studied by combining two-photon excitation and time-resolved photoelectron imaging techniques. The lifetimes of the F₁A₁ and F₁B₁ states of H₂O (D₂O) were derived to be 1.0±0.3 (1.9±0.4) and 10±3 (30±10) ps, respectively. We propose that the F₁A₁ state mainly decays through the D state, due to the nonadiabatic coupling between them, while the F₁B₁ state decays through the F₁A₁ state via Coriolis interaction.     

A Comparative Simulation: Difference between Chemical Grafting and Physical Doping of Cellulose by Using Polysilsesquioxane

In order to study the effect of different modification methods on polysilsesquioxane (POSS) modified cellulose, a molecular dynamics method was used to establish a pure cellulose model and a series of modified models modified by polysilsesquioxane in different ways. And their thermodynamic properties were calculated. The results showed that the performance of cellulose models was better than that of unmodified model, and the modified effect was the best when two cellulose chains were grafted onto polysilsesquioxane by chemical bond (M2 model). Compared with pure cellulose model, the cohesive energy density and solubility parameters of M2 model are increased by 9%, and the values of tensile modulus, bulk modulus, shear modulus and Cauchy pressure increased by 38.6%, 29.5%, 41.1% and 29.5%, respectively. In addition, the free volume fraction and mean square displacement of each model were calculated and analyzed in this work. Compared with the pure cellulose model, the molecular chain entanglement of cellulose was increased due to the existence of the chemical bonds in the M2 model, which made the cellulose molecular chains occupy more free volume, so that the system had a smaller free volume fraction, inhibited the chain movement of cellulose chains, and thus improved the thermal stability of cellulose.     

摄像机标定精度研究中的图像及数据处理问题

在计算机视觉测量系统中，摄像机的标定精度对保证测量结果的可靠性起着至关重要的作用，本文利用数学形态学探讨了图像处理的精度，并论述了豪斯荷尔德矩阵分解法在确保求解数值稳定性中的作用，最后通过对标定块上特征点进行三维重建的精度分析，验证了摄像机的标定精度。     

2-羟基吡啶S1态超快动力学

本文利用飞秒时间分辨的光电子成像技术研究了2-羟基吡啶分子在276.9∽250.0 nm波长范围的紫外光激发条件下S₁态的衰变动力学. 根据衰变动力学的泵浦波长相关性,提出了一种衰变机制. 在276.9 nm泵浦波长下,S₁态主要通过系间穿越到更低的三重态衰变. 在264.0 nm泵浦波长下,系间穿越到三重态和内转换到基态的通道同时存在. 在250.0 nm泵浦波长下,内转换到基态过程占据主导.