LiGd(W_yMo_(1-y))_2O_(8-x/2)F_x∶Eu~(3+)红色荧光粉的制备和发光特性

采用高温固相法制备了LiGd(W_yMo_(1-y))_2O_(8-x/2)F_x∶0.4Eu~(3+)(x=0~1,y=0~1)系列白光LED用红色荧光粉。通过扫描电子显微镜、X射线衍射仪、红外光谱仪、荧光光谱仪对荧光粉的形貌、结构、光学性能进行了表征。结果表明,Eu~(3+)、F-和WO_4~(2-)的掺杂没有改变LiGd(MoO_4)_2的四方晶系白钨矿结构;F~-和WO_4~(2-)最佳掺杂量分别为x=0.6,y=0.4。在396 nm激发下,LiGd(W_(0.4)Mo_(0.6))_2O_(7.7)F_(0.6)∶0.4Eu~(3+)的发光强度比未掺杂样品提高了60%,量子效率可达66.23%。当温度升高至100℃时,样品的发射强度降为25℃时的76.6%。在460 nm激发下,样品的最强窄带发射峰位于617 nm处,归属于~5D_0→~7F_2跃迁,色坐标为(0.649 9,0.346 3)。5D0能级的荧光寿命曲线遵循单指数规律衰减,随着F-掺杂浓度的增加,5D0能级的荧光寿命不断增加,归因于低声子能量的F-掺入有效减小了能量的无辐射跃迁概率。所制备的LiGd(W_(0.4)Mo_(0.6))_2O_(7.7)F_(0.6)∶0.4Eu~(3+)荧光粉有望应用于白光LED。     

LASING FROM A DYE-DOPED PENDANT DROP AND ITS PRECESSION

We have observed lasing from the rim of dye-doped ethylene glycol pendant drops. Spatial-resolved spectral measurements show that the lasing wavelength varies along a vertical rim of the drop. Time-resolved measurements indicate that lasing precession occurs within the drop. Various lasing patterns due to lasing precession are explained. The measured precession periods for different pumping points are in good agreement with the calculated values based on morphology-dependent resonance theory.     

双显色剂高灵敏协同显色反应的研究——钼-溴邻苯三酚红-乙基紫体系

本文研究了在聚乙烯醇存在下,钼(Ⅵ)与溴邻苯三酚红和碱性染料-乙基紫产生的协同显色反应。探讨了利用协同显色反应进行分光光度测定痕量钼的可能性。在乙酸介质中,钼(Ⅵ)与溴邻苯三酚红和乙基紫形成[EV]₃[MoO₂(BPR)]离子缔合型配合物,其吸收峰位于535nm,相应试剂(BPR+EV)的吸收峰则位于640nm。摩尔吸光系数e₅₃₆=1.70×10⁵L·mol^-1·cm^-1。双峰双波长法可使灵敏度倍增。Δε_535～640=3.20×10⁵L·mol^-1。钼含量为0～0.16^μg/mL时,吸光度遵守比尔定律。桑德尔灵敏度(S)为0.00057μg/cm²。反应具有较高的选择性,除锗、钛、钨、钒有较严重干扰以外,其它常见金属离子不干扰钼的显色。根据配合物的组成,推测了它的可能结构。     

纳米银粒子表面包覆分子共振吸收峰的红移现象

本文首次发现了两种电性不同的染料分子若丹明6G及荧光素钠包覆纳米银粒子时,染料分子共振吸收峰的红移现象,以及产生红移的条件。前者只有在KC1、KBr、KI等电解质存在时才产生红移;而后者则无需这些电解质存在。其红移量分别为27um及13nm.并对产生红移的机理进行了讨论。     

钪 钇茜素红S异多核络合物极谱吸附波的研究

报道了钪钇茜素红Ｓ异多核络合物的形成及该异多核络合物极谱吸附波测定钪的最佳实验条件。用此方法测定了纯氧化钇中的微量钪, 并探讨了该极谱波的性质和电极反应机制。在单扫描示波极谱上用单纯形法和改良的平衡移动法测得该异多核络合物组成的摩尔比为： ｘＳｃ３＋ ∶ｘＹ３＋ ∶ｘＡＲＳ＝１∶２∶５ 。     

Green biosynthesis,characterization, and cytotoxic effect of magnetic iron nanoparticles using Brassica Oleracea var capitata sub var rubra (red cabbage) aqueous peel extract

The green method of nanoparticle synthesis, which is an environment and living-friendly method, is an updated subject that has appeared as an alternative to conventional methods such as physical and chemical synthesis. In this presented study, the green synthesis of magnetic iron oxide nanoparticles (IONPs) from iron (III) chloride by using Brassica oleracea var. capitata sub.var. rubra aqueous peel extract has been reported. The prepared IONPs were characterized with fourier-transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV-VIS), zeta potential, scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). The cytotoxic effects of IONPs on MCF-7 breast cancer cell line were studied by MTT assay, and migrative effect of its were carried out by the wound healing assay. It was found that the mean particle size of IONPs was 675 ± 25 nm, and the polydispersity index was 0.265 PDI. It was also determined that these nanoparticles had an anti-proliferative impact on the MCF-7 breast cancer cell line depending on the dosage. Characterization results support the successful synthesis of nanoparticles, and the dose-dependent cytotoxic effects of nanoparticles on MCF-7 cells also make it a potential chemotherapeutic agent for breast cancer treatment.     

有机染料TMQ掺杂的SiO2薄膜的光谱特性

采用溶胶 -凝胶法合成了紫外波段有机染料 TMQ掺杂的 Si O2 薄膜和块体材料。薄膜中掺杂的染料浓度高达 1.2 4× 10 -2 mol/ L,块体材料中染料浓度可掺至 1.5× 10 -3 mol/ L。由于Si O2 “笼”的束缚作用 ,在吸收光谱中未观察到二聚体的特征谱带 ,在荧光光谱中未观察到荧光猝灭现象 ;同时由于 Si O2 “笼”的极化作用 ,其吸收峰和发射峰的位置相对于其在环己烷溶液中的吸收峰和发射峰位置发生了 10 nm左右的红移。     

酸性红褪色分光光度法测定食盐中碘的含量

研究了在H_2SO_4-KBr的介质中,碘酸钾能够氧化酸性红并使之褪色,且褪色的程度与碘酸根的含量在一定范围内有很好的线性关系,从而建立了一种新的测定碘的方法。实验结果表明,酸性红的最大吸收波长为510nm,碘的含量在0～50μg/50mL范围内,符合比耳定律,其回归方程为△A=0.004 13C+0.032 14,相关系数R2=0.998 3,检出限为0.78μg/50mL。方法操作简单,快速准确,用于食盐中碘含量的测定,结果令人满意。     

Based on Multi-Activity Integrated Strategy to Screening,Characterization and Quantification of Bioactive Compounds from Red Wine

According to French Paradox, red wine was famous for the potential effects on coronary heart disease (CHD), but the specific compounds against CHD were unclear. Therefore, screening and characterization of bioactive compounds from red wine was extremely necessary. In this paper, the multi-activity integrated strategy was developed and validated to screen, identify and quantify active compounds from red wine by using ultra high performance liquid chromatography-fraction collector (UHPLC-FC), ultra fast liquid chromatography-quadrupole-time-of-flight/mass spectrometry (UFLC-Q-TOF/MS) and bioactive analysis. UHPLC-FC was employed to separate and collect the components from red wine, which was further identified by UFLC-Q-TOF/MS to acquire their structural information. Furthermore, the active fractions were tested for antioxidant activity, inhibitory activity against thrombin and lipase activities in vitro by the activity screening kit. As the results, there were 37 fractions had antioxidant activity, 22 fractions had thrombin inhibitory activity and 28 fractions had lipase inhibitory activity. Finally, 77 active components from red wine were screened and 12 ingredients out of them were selected for quantification based on the integration of multi-activity. Collectively, the multi-activity integrated strategy was helpful for the rapid and effective discovery of bioactive components, which provided reference for exploring the health care function of food.     

基于玻璃光波导检测氯化氢气体方法的研究

氯化氢等气体的检测在环境监测和化学工业等许多领域中具有重要意义.本文介绍以玻璃光波导元件和消逝波的吸收为基本原理来检测氯化氢等酸性气体的一种新方法.钾离子交换玻璃光波导是通过在400℃熔化的硝酸钾(KNO3)中浸没显微镜载玻片(尺寸为76×26×1 mm)(30min)而制作的.刚果红作为敏感试剂,采用匀胶机做成薄膜固定在钾离子交换玻璃光波导表面.文中论述了实验装置和响应特征,本元件具有响应快,灵敏度高等特点,并且检测限在0.4 mg/m3以下.