TZT/AC/PMMA体系光谱烧孔及激光诱导的填孔效应的研究

报道四苯并卟啉锌/芳晴/有机玻璃TZT/AC/PMMA体系光化学烧孔的光谱稳定性、多重烧孔及激光诱导的填孔效应。 关键词：     

沉积在液体衬底上连续铝薄膜的微观结构

研究了沉积在硅油衬底表面的连续铝薄膜的微结构及其表面形貌.与沉积在单晶硅表面的铝薄膜相比,两种铝薄膜均属颗粒结构,但硅油表面的铝薄膜具有颗粒尺寸较小、大小不均匀,表面起伏较大等特点,而且在该铝薄膜边缘的下表面,有一明显的波纹状楔型结构,其斜率仅为10^-4—10^-5.实验结果表明：这一现象是由于液体衬底的热膨胀行为引起的.此外对样品的晶态也进行了研究. 关键词： 铝薄膜 液体衬底 微观结构     

Anomalous magnetic properties of an iron film system deposited on fracture surfaces of α-Al2O3 ceramics

An iron film percolation system is fabricated by vapour-phase deposition on fracture surfaces of α-Al2O3 ceramics. The zero-field-cooled （ZFC） and field-cooled （FC） magnetization measurement reveals that the magnetic phase of the film samples evolve from a high-temperature ferromagnetic state to a low-temperature spin-glass-like state, which is also demonstrated by the temperature-dependent ac susceptibility of the iron films. The temperature dependence of the exchange bias field He of the iron film exhibits a minimum peak around the temperature T=5 K, which is independent of the magnitude of the cooling field Hcf. However, for T 〉 10K, （1） He is always negative when Hcf=2kOe and （2） for Hcf= 20 kOe （1Oe≈80 A/m）, He changes from negative to positive values as T increases. Our experimental results show that the anomalous hysteresis properties mainly result from the oxide surfaces of the films with spin-glass-like phase.     

Tuning hybrid liquid/solid electrolytes by lowering Li salt concentration for lithium batteries

Hybrid liquid/solid electrolytes(HLSEs) consisting of conventional organic liquid electrolyte(LE), polyacrylonitrile(PAN), and ceramic lithium ion conductor Li_(1.5)Al_(0.5)Ge_(1.5)(PO_4)_3(LAGP) are proposed and investigated. The HLSE has a high ionic conductivity of over 2.25 × 10~(-3) S/cm at 25?C, and an extended electrochemical window of up to 4.8 V versus Li/Li+. The Li|HLSE|Li symmetric cells and Li|HLSE|Li FePO_4 cells exhibit small interfacial area specific resistances(ASRs) comparable to that of LE while much smaller than that of ceramic LAGP electrolyte, and excellent performance at room temperature. Bis(trifluoromethane sulfonimide) salt in HLSE significantly affects the properties and electrochemical behaviors. Side reactions can be effectively suppressed by lowering the concentration of Li salt. It is a feasible strategy for pursuing the high energy density batteries with higher safety.     

超临界CO_2萃取花椰菜种子油工艺优化及脂肪酸组成分析

研究超临界CO_2流体萃取花椰菜种子油,利用响应面法优化油脂萃取工艺,并分析花椰菜种子油脂肪酸构成。采用Plackett-Burman试验设计,从7个因素中筛选得到影响超临界CO_2萃取花椰菜种子油提取率的3个主要因素,分别是萃取压强、萃取温度、萃取时间。基于最陡爬坡试验设计,得到工艺参数最佳值区域。通过Box-Behnken试验开展响应面分析,得到提取率数学模型,方差分析表明该回归模型有效、可靠。确定最佳萃取条件是:萃取压强为34 MPa、萃取温度为44℃、萃取时间为91 min,预测提取率为92.17%,实际提取率为92.08±0.71%。采用GC-MS分析花椰菜种子油脂肪酸组成,结果表明其脂肪酸种类与萝卜种子油、菜籽油极为相似,但含量存在显著差异。该油品中不饱和脂肪酸含量为93.81%,单不饱和脂肪酸含量为84.65%。     

OADM环网的实验研究

研究了光分插复用器(OADM)的关键技术,重点分析了相关的实现技术,完成了利用OADM构建全光环网的实验研究,给出了重要的实验数据,包括眼图、光谱图、光信噪比、保护与恢复等,并对这些实验数据进行了分析,为光传送网的设计与构建提供了重要的参考依据.     

激光荧光光谱研究Pyrene在SiO_2表面上生成Excimer的机理

用激光荧光法研究了pyrene(芘,嵌二萘)在SiO_2表面上生成excimer(激基缔合物)的机理。在4.2°K温度下,分别用330nm和375nm的激光激发pyrene,可检测到不同的荧光光谱带;在77°K时,分别在392nm和475nm处检测pyrene在SiO_2表面上的激发光谱,也得到不同的激发谱带;说明在实验样品条件下,pyrene在SiO_2表面上有稳定的“静态”eimer存在,当激发这些eimer时,就生成excimer,从而可在475nm附近观察到excimer的特征发射带。然而,不同温度下的荧光光谱又显示出,pyrene吸附在SiO_2表面上除去由dimer受激而直接生成的excimer外,仍有部分“动态”的excimer生成,即由受激的单体pyrene分子在表面通过扩散而和另一个单体pyrene分子形成excimer(就象在溶液中一样)。     

Density Waves in One-Dimensional Granular Flows Driven by Non-Uniform Force Field

We introduce a non-uniform gravity-like force field to control the granular flow state in a quasi-onedimensional system, and study the system by the molecular dynamics simulation. We find that the granular flow under non-uniform force field can be well described by a density wave with fixed time period if a fixed particle number condition is used. The base frequency of the density wave does not depend on the position of the flow, while both the average density and oscillation amplitude of the flow vary continuously with the position. The formation of the density wave results from the aggregation of the granules in the decelerated region and the feed-back mechanism in the fixed particle number condition.     

臭牡丹黄酮类化合物提取及其抗氧化作用

研究臭牡丹中黄酮类化合物的最佳提取工艺条件及其抗氧化活性.以提取时间、料液比、提取温度、乙醇体积分数为主要影响因素,以黄酮类化合物提取率为考察指标,确定最佳提取工艺条件,并通过对亚硝酸盐、超氧阴离子自由基、羟自由基的清除效果及对猪油的抗氧化研究其抗氧化活性.结果表明,臭牡丹中黄酮类化合物的最佳提取工艺条件为提取时间2.0h、料液比1∶40（g/mL）、提取温度70℃、乙醇体积分数70％的条件下提取效果最好,臭牡丹中黄酮类化合物在各抗氧化体系中均表现出较强的抗氧化活性,且其作用具有剂量效应关系,其抗氧化活性均强于维生素C.     

一种生物柴油代用品在HZSM-5分子筛催化剂上的催化热解

为了深入了解生物柴油在ZSM-5沸石上的催化反应机理,在常压的流动反应器中进行了生物柴油代用品丁酸甲酯在氢型ZSM-5(HZSM-5)催化剂上的热解和催化热解. 热解产物使用气相色谱-质谱法定性和定量测量. 动力学模型和实验表明,气相中氢提取反应是热解过程中丁酸甲酯分解的主要途径,但在HZSM-5上,丁酸甲酯则主要通过解离生成烯酮和甲醇消耗;与无催化反应相比,丁酸甲酯在HZSM-5上的初始分解温度降低了约300 K. 并且通过Arrhenius方程获得了在催化热解和均相热解条件下丁酸甲酯消耗的表观活化能. 明显降低的表观活化能证实了HZSM-5对丁酸甲酯热解的催化性能. 此外催化剂的活化温度对HZSM-5的某些催化性能具有一定的影响. 该研究对进一步的实际生物柴油燃料的催化燃烧具有一定的指导意义.