季铵盐型光潜碱的合成及光化学特性研究

光潜碱(或光产碱剂)在光照下可以分解并释放出碱,后者可用于碱催化的反应,即可将碱催化的热反应转变为光热反应。本文以a-溴代苯乙酮分别与1,8-二氮杂双环[5.4.0]十一-7-烯(DBU)、4-甲基吡啶和3-甲基吡啶合成了三种季铵盐,再通过阴离子交换合成了以四苯基硼为配对阴离子的三种具有光化学活性的叔胺型光潜碱。采用核磁共振仪、实时红外吸收光谱(RT-IR)和紫外-可见吸收光谱(UV-Vis)等表征了合成产物的结构、跟踪了光潜碱的光化学以及光分解过程。UV-Vis表明紫外光照后三种光潜碱的吸收光谱都发生了明显变化,并在260-320 nm产生了新的紫外吸收谱带,而两种甲基吡啶的光潜碱在λmax=450nm处的吸收峰消失;RT-IR显示三种光潜碱的苯甲酰基吸收在紫外光照后消失,但产生新的C=O吸收峰,DBU光潜碱的苯甲酰基吸收在紫外光照10s后消失,而甲基吡啶光潜碱的消失要慢一些。用DBU光潜碱进行了光催化多硫醇-甲基丙烯酸羟乙酯(HEMA)的光聚合反应,RT-IR跟踪实验表明,C=C双键反应速率快,在光照300s后完全转化,而巯基在光照300s后转化率才达到66.4%;对比DBU催化多硫醇与HEMA的迈克尔加成反应,证明DBU光潜碱的光催化多硫醇HEMA光主要是通过巯-烯聚合反应。     

聚甲醛的耐光稳定化研究

讨论了聚甲醛（POM）的光老化机理、光老化特征及各种添加剂对POM的光稳定化作用，以及添加剂配合法、其它聚合物单独添加法、其它聚合物配合法等对POM耐光稳定化的效果和相应的光稳定化机理。     

聚烯烃光稳定化原理的评述

光氯化与热氧化历程的主要区别在于引发步骤。而聚烯烃发生光氧化反应归因于存在能吸收紫外线的发色基团。本文讨论了过氧化氢物与羰基化合物对聚烯烃光氧化过程的贡献,并叙述了各种紫外稳定剂的稳定化原理及作用。     

光电化学电池的原理及其应用──兼谈光电化学电池生成氯气和烧碱的可能性

本文从光电化学电池的原理和应用事例出发，提出了利用半导体电极、金属电极、氯碱工业用离子交换膜构成一个光电化学体系，探讨了用该体系生成氢气、氯气和烧碱的可能性。     

涂料的光老化与光稳定剂

分析了涂料成膜物光降解机理。介绍了丙烯酸酯类、苯乙烯类、芳香族聚酯、芳香族聚氨酯等几种主要涂料成膜物光降解行为及其降解产物,并根据成膜物的降解行为介绍了紫外光屏蔽剂、紫外光吸收剂、自由基清除剂、酚类抗氧剂等光稳定剂。     

聚甲醛耐光稳定性研究进展

综述了聚甲醛光氧老化特性和光稳定剂研究开发现状,指出了聚甲醛光稳定剂未来发展趋势。聚甲醛对抗紫外光稳定性较差,容易发生降解与氧化,添加光稳定剂有助于提高聚甲醛耐光稳定性。常用的聚甲醛光稳定剂主要包括紫外光屏蔽剂、紫外光吸收剂和受阻胺类光稳定剂等三大类,对光稳定剂的研究方向主要包括高相对分子质量化、聚合物键合化、多功能化、受阻胺低碱性化等方面。     

光电化学电池的原理及其应用

本文从光电化学电池的原理和应用事例出发，提出了利用半导体电极、金属电极、氯碱工业用离子交换膜构成一个光电化学体系，探讨了用该体系生成氢气，氯气和烧碱的可能性。     

水溶性自由基光引发剂及其研究现状

水溶性光引发剂作为一种环境友好的光引发剂,在环保水性涂料、生物材料等方面有广泛的应用前景。介绍了目前市场上常用的水溶性自由基光引发剂,并综述了国际上水溶性自由基光引发剂的研究现状。     

阿维菌素光分解及其光稳定剂的筛选

探讨了阿维菌素在太阳光及紫外光照射下的光分解现象，发现其属于光易分解物质，光分解半衰期约为3h。运用10种不同的光稳定剂处理均能一定程度的抑制阿维菌素光分解，其中以BHA抑制效果最为明显；在此基础上研究了不同浓度BHA对阿维菌素光分解的抑制效应，结果显示其抑制效果与稳定剂的浓度相关，一般处理浓度越大其抑制阿维菌素光分解的作用就越强。     

高分子材料光降解和光稳定

本文简介高分子材料光降解与光稳定术语含义以及基本概念,包括降解的成因,现象,以及光稳定的方法和机理。     

PE吹塑农用兰光母料及兰光膜的研制

本文介绍PE吹塑农用兰光母料及兰光膜的研制。通过试验,确定了兰光母料的最佳配方,母料中光转换剂C_(26)H_(16)的用量为0.06～0.08%。并以母料与基体树脂1∶25的配比原材料,吹塑成兰光膜。此膜在光照不足的弱光照射下(2万LUX以下)光透过率>75%;存放13个月后物理机械性能未出现明显变劣趋势;其耐水浸渍性较好,完全可满足播种、移栽、整个育秧生长期的实际使用期限。该膜不仅是水稻育秧专用膜,而且还可用于玉米、红薯、西瓜等作物的增产增收。     

兰光转换膜的研制及其水稻育秧效果试验

本文介绍了以LDPE与LLDPE为基料的农用兰光转换水稻育秧膜的研制与性能，以及该膜用于水稻育秧的应用效果试验。最终增产效果为5．5％。     

Enhancing photovoltaic performance of dye-sensitized solar cell by rare-earth doped oxide of Lu2O3:(Tm, Yb)

In order to increase of the photocurrent, photovoltage and energy conversion efficiency of dye-sensitized solar cell (DSSC), rare-earth doped oxide of Lu₂O₃:(Tm³⁺, Yb³⁺) is prepared and introduced into the TiO₂ film in the DSSC. As a luminescence medium, Lu₂O₃:(Tm³⁺, Yb³⁺) improves incident light harvest via a conversion luminescence process and increases photocurrent; as a p-type dopant, the rare-earth ions elevate the energy level of the oxide film and increase the photovoltage. Under a simulated solar light irradiation of 100 mW cm⁻², the light-to-electric energy conversion efficiency of the DSSC with Lu₂O₃:(Tm³⁺, Yb³⁺) doping reaches 6.63%, which is increased by 11.1% compared to the DSSC without Lu₂O₃:(Tm³⁺, Yb³⁺) doping.     

铝合金钼酸盐转化膜

通过实 验得到 了铝合金 钼酸盐 转化膜质 量膜厚与 钼酸根 离子浓度 及溶 液ｐ Ｈ 值之 间的 关系 。同 时发现加 入偏硅酸 钠或偏硼 酸钠作 协同缓蚀 剂,能显 著提高铝 合金 的抗 蚀能 力。 质量 膜厚 全部 采用 Ｉ Ｓ Ｏ１０６ 标准测定     

农用转光剂及转光膜开发进展

概述了农用转光剂及转光膜的研究和应用状况,提出了农用转光剂的分类方法、表示符号和光谱参数,讨论了农用转光剂及转光膜的发展趋势。     

具有屏蔽蓝光性能的PVA基功能薄膜的制备及性能研究

依据颜色互补原理,以聚乙烯醇(PVA)为基材,黄颜料为蓝光吸收剂,制备具有屏蔽蓝光特性的PVA基功能薄膜.通过调控黄颜料的种类和含量,研究了不同种类的黄颜料对蓝光屏蔽性能和薄膜透光率的影响.研究发现,耐晒黄的蓝光屏蔽性能最佳,且当其含量为0.5％时,蓝光屏蔽性能达到饱和状态.     

作物转光喷施液的制备及性能研究

将CaS：Eu荧光粉添加到高分子溶液中配成转光液,喷涂后自然条件下干燥成膜。探讨了分散方法对转光液所成薄膜光学性能的影响,确定了较优的分散方法;测试了薄膜的荧光光谱、透光率、荧光抗衰减性能。结果表明,转光液可在植物叶面上快速成膜,薄膜具有吸收紫外光和绿光发射645nm红光的作用,转光行为能促进植物光合作用,薄膜可见光区的透光率在70％以上,荧光抗衰减性能较好,这种转光喷施液是一种没有污染而十分有效的“光肥”。     

Photo-thermal process on BiFeO3 thin film

This study demonstrates that a photo-thermal process, namely a concurrently light illumination during annealing, is an effective method to develop a high-quality BiFeO₃ (BFO) thin film. The wavelength-dependent light effect, which is determined by the photo absorption property of the sol-gel synthesized BFO solution, assisted in the decomposition of organic residues within the film during the thermal history. The photo absorption property of the BFO precursor varied with an exponential function of temperatures. By using a combination of an appropriate wavelength light illumination and a suitable temperature thermal annealing, the BFO film formed in a uniform dense microstructure with near-stoichiometric composition which was difficult to achieve with a traditional thermal process. We proposed the application of light illumination under thermal process would improve the reaction sequences of the constituent species as well as the crystallization mechanism of BFO, then providing the flexibility to control the film characteristics.     

Photopolymer kinetics using light intensity gradients in high-throughput conversion analysis

Light intensity gradients and light exposure time gradients were combined to produce contours of constant dose on a sample substrate. These polymerized samples were subsequently analyzed using high-throughput Fourier transform infrared spectroscopy to measure conversion as a function of both gradients. Three (meth)acrylate monomers were analyzed over light doses ranging from 0 mJ/cm² to 920 mJ/cm², demonstrating that in thin films, higher light intensities at a constant light dose produce higher conversion due to a decreased oxygen inhibition time and larger thermal excursions. At a light dose of 75 mJ/cm², the conversion of 2-ethylhexyl acrylate increases from 40 ± 2% at a light intensity of 0.9 mW/cm² to 59 ± 3% at 7.2 mW/cm². The two acrylate monomers exhibited rapid photopolymerization up to a specific conversion, after which additional radiation dose produced only marginal increases in overall conversion. For hexanediol diacrylate, a light dose of 300 mJ/cm² was the minimum amount required to reach the maximum conversion over the entire range analyzed. For the dimethacrylate system, a similar effect was seen, with a reduced oxygen inhibition time and conversion above 70% showing a similar conversion at a constant light dose of 500 mJ/cm². In all three systems, dose contours were used to determine a range of light intensities at which a statistically similar conversion would occur for a specified light dose.     

Fabrication of hydrophobic surface with hierarchical structure on Mg alloy and its corrosion resistance

A hydrotalcite/hydromagnesite conversion coating with hierarchical structure has been fabricated on a Mg alloy substrate by in situ hydrothermal crystallization method. A MgO layer existing between the hydrotalcite/hydromagnesite film and the substrate was formed prior to the hydrotalcite/hydromagnesite film during the crystallization process. After surface treatment with silane coupling agent, the surface of conversion coating changes from hydrophilic to hydrophobic. Scanning electron microscopy (SEM) revealed that the silylated conversion coating with hierarchical structure maintains the original rough surface of which was composed of numerous micro-scale flakes and beautiful flower-like protrusions. Polarization measurements have shown that the hydrophobic conversion coating exhibited a low corrosion current density value of 0.432 μA/cm², which means that the hydrophobic conversion coating can effectively protect Mg alloy from corrosion. Electrochemical impedance spectroscopy (EIS) showed that the impedance of the hydrophobic conversion coating was 9000 Ω. It means that the coating served as a passive layer with high charge transfer resistance.