ICP—AES法快速测定植酸中钙

植酸,学名环已醇六磷酸酯,分子式C_6H_(18)O_(24)P_6,其经济价值高,用途广,常以40％～70％水溶液作为商品出售。植酸中钙含量的多少,往往作为其商品是否合格的指标之一。     

超声雾化ICP—AES的研究

报道了超声雾化器改装后作为电感耦合等离子体发射光谱（ＩＣＰ－ＡＥＳ）的进样装置。研究了多元素同时分析的最佳实验条件。在高频功率为３．１×０．７６ＫＷ、载气一０．７２Ｌ／ｍｉｎ和观察高度１．３ｃｍ的条件下，对大多数元素其谱线较经而背景辐射较弱。     

仲钨酸铵中17种杂质元素的ICP—AES法测定

钨有丰富的光谱线,在仲钨酸铵中各种杂质含量通常为0.0x～10μg·g~(-1)范围。由于钨对许多元素都存在不同程度的光谱干扰,包括背景干扰和谱线重迭,或非光谱干扰,其干扰综合量大于杂质本身含量,所以不分离钨很难准确测定其含量。文献[1]曾用离子交换分离富集钨酸钠中钙、镁,然后用ICP-AES法测定。测定高含量钨基体样品中多种杂质尚未见报道。本文研究用氨水-过氧化氢分解仲钨酸铵,以钨酸形式沉淀钨与其它元素分离,然后用ICP-AES法测定其中17种杂质,方法分离效果好、快速、准确,加标回收率为95％～108％。 1 试验部分 1.1 仪器与试剂 JY70P Ⅱ(法国):高压4.1kV,阳流400mA;栅流170mA;冷却气13L·min~(-1),雾化气0.3L·min~(-1),保护气0.1L·min~(-1)(测K、Na、Li用0.6L·min~(-1)),溶液提升量1.4ml·min~(-1);观察高度14mm;积分时间20s。     

Photoconductivity in Mesostructured Thin Films

Mesostructured silica films are widely studied due to their different structures, properties and variety of possible applications. Sodium dodecyl sulfate (SDS)-templated sol-gel silica films possess highly ordered lamellar phase structure. It is expected that molecules and polymer chains line up with these layered structures when incorporated into the films. Mesostructured thin films were doped with Dispersed Red 1 (DR1) and carbazole ((C₆H₄)₂NH)). The films were poled by corona discharge at 120 C. Absorption spectra were recorded as function of the polarization time. Dependence of the absorption coefficient with polarization time was fitted with a Langevin-Debye equation. It shows a saturation level after 60 minutes of polarization. We compare the efficiency of mesostructured thin films with that of amorphous films. The photoconductivity technique was used to determine the charge transport mechanism of these films. From current density versus electrostatic applied field, the parameters for the photovoltaic effect and photoconductivity were determined. Results of the mesostructured thin films are also compared to those of KNbO₃ crystals.     

自组装方法制备有序微孔薄膜

本文对近年来自组装方法制备有序微孔薄膜的研究进行了综述,总结了固体基板展开法制备有序微孔薄膜的形成机理,对成膜材料,成膜的影响因素和微孔阵列排列的形成条件等方面进行了详细的介绍和分析,并对自组装方法制备微孔薄膜的应用前景作了探讨。     

Thin Films of Photoactive Polymer Blends

Photoactive polymer blends: Films consisting of two photoactive homopolymers, MEH‐PPV and P3HT, are prepared via spin coating. Investigation of the lateral domain distance inside the blended film, performed by using grazing incidence small angle X‐ray scattering techniques, shows that the theoretically predicted blending ratio seems most promising (see figure).

     

Photovoltaic Behaviour of Titanyl Phthalocyanine Thin Films and Titania Bilayer Films

Summary: Titanyl phthalocyanine (TiOPc) thin films were prepared using evaporation and surface polymerization by ion-assisted deposition (SPIAD) in a vacuum deposition system. These films were characterized by means of ultraviolet and X-ray photoelectron spectroscopy as well as UV/Vis absorption spectroscopy. Valence band and elemental content indicated that phthalocyanine electronic and chemical structures were largely preserved during SPIAD. Further, bilayer thin films of titania (TiO₂) and SPIAD TiOPc were prepared. TiO₂ film was deposited by reactive magnetron sputtering of TiO₂ target. Study of the structured samples was focused on the optical and electrical properties of the composite films. The films were characterized by non-contact photovoltage measurements and UV-Vis spectroscopy. These results suggest there is a possibility to use these bilayer thin films in photovoltaic solar cells, however further experiments to improve conductivity of the films will be required.     

MXenes Thin Films: From Fabrication to Their Applications

Two-dimensional MXenes possessed exceptional physiochemical properties such as high electrical conductivity (20,000 Scm⁻¹), flexibility, mechanical strength (570 MPa), and hydrophilic surface functionalities that have been widely explored for energy storage, sensing, and catalysis applications. Recently, the fabrication of MXenes thin films has attracted significant attention toward electronic devices and sensor applications. This review summarizes the exciting features of MXene thin film fabrication methods such as vacuum-assisted filtration (VAF), electrodeposition techniques, spin coating, spray coating, dip-coating methods, and other physical/chemical vapor deposition methods. Furthermore, a comparison between different methods available for synthesizing a variety of MXenes films was discussed in detail. This review further summarizes fundamental aspects and advances of MXenes thin films in solar cells, batteries, electromagnetic interference shielding, sensing, etc., to date. Finally, the challenges and opportunities in terms of future research, development, and applications of MXenes-based films are discussed. A comprehensive understanding of these competitive features and challenges shall provide guidelines and inspiration for further growth in MXenes-based functional thin films and contribute to the advances in MXenes technology.     

Encapsulation of Proteins in Bulk and Thin Film Sol-Gel Matrices

This paper considers the nature of the interactions between the sol-gel derived inorganic matrix and a specific biomolecule, cytochrome c. Optical absorption and impedance spectroscopies are used to characterize the influence of synthesis conditions on the protein’s stability and conformation within the silica matrix. In some instances, encapsulation within the sol-gel matrix provides stabilization. For example, protein denaturation is reversible and aggregation is prevented. Moreover, the drying process does not negatively affect the protein; it is possible to regenerate the aged gel state by rehydration. The flexibility of the sol-gel process enables high quality cytochrome c-doped SiO₂ thin films to be prepared. These films possess the characteristic reactivity and chemical function of cytochrome c in solution.     

甲胺铅碘前驱体薄膜放置过程中物质结构演变及对后续钙钛矿薄膜的影响

系统研究了甲胺铅碘(MAPbI_3)前驱体薄膜在室温大气中放置过程的物质结构变化过程,发现甲胺铅碘前驱体进一步生成了更多的MAPbI_3钙钛矿,大约220 min后MAPbI_3钙钛矿不再增加而且仍有前驱体。此外还分析了这种结构演变对后续钙钛矿薄膜热退火结果的影响,发现放置后的甲胺铅碘前驱体薄膜退火过程中的X射线衍射强度和紫外-可见吸收均比新制备的薄膜的低,而且通过原子力表面形貌图的对比发现,放置后的薄膜热退火后的薄膜晶体尺寸远小于新制备的甲胺铅碘前驱体薄膜热退火后的晶体尺寸,放置后的薄膜晶体尺寸约为0.2μm,新制备的薄膜晶体尺寸约为1.1μm。主要原因在于:甲胺铅碘前驱体薄膜由于在室温大气中放置过程中多生成了部分甲胺铅碘(MAPbI_3),因此晶体成核数量较多,晶粒数量增加,晶体存在较多缺陷,薄膜结晶度低,所以退火时X射线衍射强度和光谱强度较低,同时晶粒尺寸变小。研究为探讨甲胺铅碘钙钛矿生成机理提供了新的思路和方向,属于甲胺铅碘钙钛矿薄膜性质的基础性研究,对实际生产和工业应用有一定指导意义。