通过开关单元调节赋予荧烷水致变色性质及喷水打印应用

喷水无墨打印概念的提出对于改善环境污染、资源消耗等问题做出了突出贡献,然而已有的水致变色染料种类较少且开发困难。 本文通过对荧烷化合物(9-(2-羧基苯基)-3,6-双(二乙氨基)占吨翁氯化物,罗丹明B)开关单元进行调控,从而调节分子开关环的动态平衡,实现了酸致变色染料到水致变色染料的调节,并展现了其在喷水无墨打印方面的应用。 该荧烷衍生物水致变色染料的合成可以直接以市售的荧烷化合物为原料,通过两步反应简单修饰,得到的染料摩尔吸光系数达到1×10⁵,所制备的打印纸水写前后反射率变化50%,有望大规模应用到喷水无墨打印中。     

烯烃的氢甲酰化串联反应研究

氢甲酰化串联反应是在氢甲酰化反应的基础上,与一个或多个不同类型的反应“一锅法”实现醛类化合物的后续定向转化,得到新的有机分子的合成方法。该反应的产物在日化工业、农业、医药中间体的生产中具有十分重要的用途。本文首先简述了近年来烯烃氢甲酰化串联反应制备高附加值化学品的重要性,随后重点介绍了几种常见的烯烃氢甲酰化串联反应:“异构化-氢甲酰化”串联反应、“氢甲酰化-缩醛化”串联反应、“氢甲酰化-氢化”串联反应和“氢甲酰化-(还原)胺化”串联反应等,以及其在设计新型(多功能)催化剂体系和高效合成目标产物方面的研究进展,最后总结了烯烃氢甲酰化串联反应存在的问题以及对未来发展趋势进行了展望。     

凝聚态化学的研究对象与主要科学问题

本文提出了“凝聚态化学(Condensed Matter Chemistry)”的概念,提出其研究对象是由传统化学上被视为反应主体的原子、离子以及分子等“基本粒子”,藉“稳定的粘连关系”凝聚形成的具有特定组成、多层次结构与性质、功能的物质凝聚态。本文以固态为例,讨论了(1)凝聚态的多层次结构;(2)凝聚态的化学性质与化学反应;(3)凝聚态构筑化学中的前沿科学问题;(4)凝聚态化学中的高新表征方法与技术的发展与开拓。并对四个领域中的主要科学问题进行了比较深入的探讨,为进一步再认识传统化学,特别是对其中心问题,即化学反应的再认识提供了方向与基础,为开展“凝聚态的多层次结构-化学性质与化学反应-凝聚态物质的构筑定向合成与精准制备”三个方面的关系研究,总结规律与“分态”建立“凝聚态结构理论”与“凝聚态化学反应理论”,建设“凝聚态化学”提供了科学体系与内容,并为进一步开展“凝聚态工程学”研究提供了前提与基础。     

Cu2O/ZnO的形貌可控制备及光催化性能

以CuSO₄和ZnCl₂为原料, 采用温和的液相还原法制备得到Cu₂O/ZnO微米结构高效光催化剂. 研究了不同[Cu²⁺]/[Zn²⁺]比条件下所得Cu₂O/ZnO复合物的形貌和光催化活性. 通过5.5 h的光照, Cu₂O/ZnO光催化剂对甲基橙染料的降解率为(77.5±0.1)%. 将多形貌Cu₂O/ZnO复合物作为阳极, 铂片作为对电极, 中间注入甲基橙溶液, 组装“三明治”结构拟电池, 研究了复合物的光降解机制.     

喷墨打印聚合物薄膜均匀性调控研究进展

聚合物发光显示材料具有发光颜色在全可见光区可调、可溶液简单加工及适用于柔性大面积基底的特点,成为目前研究的热点。 在聚合物发光薄膜图案化技术中,喷墨打印因为具有加工过程简单高效、适用于溶液方式加工、柔性的加工过程等特点而被认为是最具有应用潜力的技术。 高质量聚合物薄膜的制备是高精度发光显示器件制作的关键,但喷墨打印液滴在干燥过程中通常伴随着“咖啡环”现象,造成薄膜不均匀沉积。 因此,消除“咖啡环”现象,实现聚合物薄膜的均匀沉积,是喷墨打印高性能器件的重要研究方向。 本文主要论述了“咖啡环”效应的产生机理,如何抑制喷墨打印聚合物薄膜加工过程中的“咖啡环”效应,最终实现聚合物薄膜均匀性调控。     

从铜离子、酸中心与铝分布的关系分析不同模板剂制备Cu-SSZ-13的NH3-SCR性能

铜离子改性的SSZ-13沸石是以氨气为还原剂选择催化还原柴油发动机尾气中氮氧化物反应(NH₃-SCR)的优良催化剂。本文综述并具体分析了酸中心位点对于Cu-SSZ-13中铜离子落位、迁移的影响,以及骨架铝分布对其决定性的作用,强调了“成对”酸中心,“强铝对”对于催化剂水热稳定性的重要作用,并总结了目前控制“铝对”形成的方法。以此为基础分析了不同有机模板剂、共模板剂法制备的Cu-SSZ-13在催化NH₃-SCR反应中的表现,为使用廉价模板剂或共模板剂替代TMADaOH合成具有良好NH₃-SCR催化活性和水热稳定性的Cu-SSZ-13提供参考。     

银纳米粒子簇的设计、 制备和表面增强拉曼光谱

通过匹配激光光斑直径与胶体微球的尺寸, 设计制备了银纳米粒子的表面增强拉曼散射(SERS)基底, 并将其用于研究单个银纳米粒子簇的表面增强拉曼光谱. 在制备纳米粒子的过程中, 考察了等离子体刻蚀时间与银沉积厚度对“单”银纳米粒子结构与形貌的影响. 将吡啶、 巯基苯和罗丹明R6G作为SERS探针分子, 研究了其SERS效应, 通过荧光共振能量转移(FRET)机理, 实现了染料分子在单银纳米粒子簇上的SERS效应. SERS光谱测试与相关计算结果表明, 单个银纳米粒子簇的拉曼增强因子能够达到约10⁶.     

石墨烯迷你马达的自组装制备及其乙醇驱动运动和油品吸附性能

石墨烯三维(3D)宏观体多集中在厘米尺度并为实心对称结构,且存在“小尺寸”和“低密度”难以协调的矛盾。 本文以氧化石墨烯为前驱体、苯胺为交联剂,在电动搅拌下通过剪切力驱动聚集和毛细管力干燥协同自组装制备球状氧化石墨烯水凝胶,经过高温还原得到石墨烯迷你马达。 所得石墨烯迷你马达具有尺寸小(直径2~5 mm)、密度低(0.2~0.7 g/cm³)、内部空心结构以及疏水亲油的性能。 上述结构特征赋予其乙醇驱动运动和油品吸附性能。 研究表明,充分浸泡乙醇的石墨烯迷你马达在水中可以展现出自转速度3 r/s的无规则快速运动;对水中植物油的饱和吸附量约为794.9 mg/g。     

Al-MOF基多级孔Al2O3固定化酶反应器的构筑及构效关系研究

针对生物酶在固相载体负载后存在的催化活性与稳定性之间“此消彼长”的问题, 本工作采用“自牺牲模板”策略以铝基金属有机骨架材料(Al-MOF)为前驱体设计制备多级孔Al₂O₃ (MHAl₂O₃)材料, 再以“聚多巴胺(PDA)”仿生膜对材料表面进行功能化修饰后用以固载辣根过氧化物酶(HRP). 通过调节前驱体的煅烧温度来实现载体孔径大小的调控, 探讨了载体的孔道限域效应对固定化酶反应器催化活性的影响, 所得固定化酶反应器的热稳定性和重复使用性显著提高. 为了解析固定化酶反应器的构效关系, 采用酶动力学和热动力学参数研究了固定化酶反应器催化过程中酶与底物的相互作用, 结果表明固载后酶分子对底物的亲和性和专一性得到提升. 将固定化酶反应器用于模拟废水中苯胺黑药的催化降解时, 表现出非常高效的催化效率.     

(羟基喜树碱@胆酸钠)-层状双金属氢氧化物纳米杂化物的组装及表征

采用“药物修饰-共组装”法制备了(羟基喜树碱@胆酸钠)-层状双金属氢氧化物纳米杂化物. 先用胆酸钠(SCL)包裹羟基喜树碱(HCPT)形成胶束, 再与微反应器制备的层状双氢氧化物(LDH)纳米片共组装形成纳米杂化物, 其载药量可达12.9%, 杂化物中HCPT以高生物活性的内酯形式存在. 采用聚乙二醇(PEG)和羧甲基纤维素(CMC)分别对所制备的(HCPT@SCL)-LDH纳米杂化物进行了表面修饰, 结果表明, 纳米杂化物的分散性得到明显改善; PEG的修饰效果优于CMC, 所获得的PEG-(HCPT@SCL)-LDH杂化物的平均粒径可小至约70 nm, 具有良好的分散性和药物缓释效果. 其药物释放过程可用准二级动力学方程描述, 颗粒内部扩散是药物释放过程的控制步骤.     

A Convenient Synthesis of Antihyperlipoproteinemic Agent Gemfibrozil

A new synthesis of antihyperlipoproteinemic agent 2,2-dimethyl-5-(2,5-dimethylphenoxy)pentanoic acid (gemfibrozil, 1) is developed via hydrogenolysis of a novel β-lactone 6, prepared from [2+2] cycloaddition of 3-(2,5-dimethylphenoxy)propanal with dimethylketene. The mild conditions applied in this process are especially convenient for the preparation of gemfibrozil on an industrial scale of production.     

Adsorption of cationic methylene blue dye using microwave-assisted activated carbon derived from acacia wood: Optimization and batch studies

This study assesses the performance of optimized acacia wood-based activated carbon (AWAC) as an adsorbent for methylene blue (MB) dye removal in aqueous solution. AWAC was prepared via a physicochemical activation process that consists of potassium hydroxide (KOH) treatment, followed by carbon dioxide (CO₂) gasification under microwave heating. By using response surface methodology (RSM), the optimum preparation conditions of radiation power, radiation time, and KOH-impregnation ratio (IR) were determined to be 360 W, 4.50 min, and 0.90 g/g respectively, which resulted in 81.20 mg/g of MB dye removal and 27.96% of AWAC’s yield. Radiation power and IR had a major effect on MB dye removal while radiation power and radiation time caused the greatest impact on AWAC’s yield. BET surface area, mesopore surface area, and pore volume of optimized AWAC were found to be 1045.56 m²/g, 689.77 m²/g, and 0.54 cm³/g, respectively. Adsorption of MB onto AWAC followed Langmuir and pseudo-second order for isotherm and kinetic studies respectively, with a Langmuir monolayer adsorption capacity of 338.29 mg/g. Mechanism studies revealed that the adsorption process was controlled by film diffusion mechanism and indicated to be thermodynamically exothermic in nature.     

维布妥昔单抗关键中间体的合成工艺优化

本研究对维布妥昔单抗关键中间体(1)的合成工艺进行了改进与优化。以芴甲氧羰基-L-缬氨酸琥珀酰亚胺酯(2)为起始原料,先后经酯的氨解反应、酰胺化、Fmoc脱保护、酰胺化与酯交换反应制得目标产品1,总收率11.6%,纯度99.2%,产物结构经1H NMR, 13C NMR和HRMS表征。优化后的工艺路线具有反应条件温和、可操作性强、生产过程更安全的特点。在初步放大试验中,首步投料量达百克级别,并已完成三批工艺验证,适合于工业化生产。     

A novel and practical synthesis of substituted 2-ethoxy benzimidazole: candesartan cilexetil

A novel and practical synthetic route for the preparation of candesartan cilexetil from methyl 2-amino-3-nitrobenzoate is described. The key steps are the reaction of methyl 2-bromo-3-(diethoxymethyleneamino)benzoate with (2′-(1-trityl-1H-tetrazol-5-yl) biphenyl-4-yl) methanamine and the final formation of 2-ethoxy benzimidazole ring via intramolecular N-arylation. The final ring closure process could be utilized to prepare other 2-substituted benzimidazoles. The method is simple for operation and suitable for industrial production.     

Esterification Synthesis of Ethyl Oleate in Solvent-Free System Catalyzed by Lipase Membrane from Fermentation Broth

In this study, the immobilized lipase was prepared by fabric membrane adsorption in fermentation broth. The lipase immobilization method in fermentation broth was optimized on broth activity units and pH adjustments. The viscose fermentation broth can be used with a certain percentage of dilution based on the original broth activity units. The fermentation broth can be processed directly without pH adjustment. In addition, the oleic acid ethyl ester production in solvent-free system catalyzed by the immobilized lipase was optimized. The molar ratio of ethanol to oil acid, the enzyme amount, the molecular amount, and the temperature were 1:1, 12% (w/w), 9% (w/w)(based the total amount of reaction mixture), and 30 °C, respectively. Finally, the optimal condition afforded at least 19 reuse numbers with esterification rate above 80% under stepwise addition of ethanol. Due to simple lipase immobilization preparation, acceptable esterification result during long-time batch reactions and lower cost; the whole process was suitable for industrial ethyl oleate production.     

Natural Dyeing of Modified Cotton Fabric with Cochineal Dye

Natural dyes are not harmful to the environment owing to their biodegradability. For dye application to textiles, salts are necessary as mordant or electrolytes and make an environmental impact. In this paper, the influence of cationization during mercerization to the dyeing of cotton fabric with natural dye from Dactylopius coccus was researched. For this purpose, bleached cotton fabric as well as fabric cationized with Rewin OS was pre-mordanted using iron(II) sulfate heptahydrate (FeSO₄·7H₂O) and dyed with natural cochineal dye with and without electrolyte addition. For the characterization of surface changes after cationization, an electrokinetic analysis on SurPASS was performed and compared to pre-mordanting. For determination of dye exhaustion, the analysis of dye solution was performed on a UV/VIS spectrophotometer Cary 50 Solascreen. Spectrophotometric analysis was performed using a Datacolor 850 spectrophotometer, measuring remission ”until tolerance” and the whiteness degree, color parameters, color depth (K/S), and colorfastness of dyed fabric were calculated. Levelness was determined by visual assessment. Cationized cotton fabrics showed better absorption and colorfastness. Pre-mordanting and cationization showed synergism. The electrolytes improved the process of dye absorption. However, when natural dyeing was performed on cotton fabric cationized during mercerization, similar chromacity, uniform color, and colorfastness were achieved with and without electrolyte, resulting in pure purple hue of cochineal. For achieving a violet hue, pre-mordanting with Fe-salt was needed. Therefore, salt can be reduced or even unnecessary, which makes this process of natural dyeing more environmentally friendly.     

Optimization of sequencing conditions using near-infrared lifetime identification methods in capillary gel electrophoresis

We have investigated the sample preparation and electrophoresis conditions necessary to prepare DNA sequencing samples appropriate for use with near-infrared (IR) fluorescent labels with dye identification accomplished via lifetime techniques. It was found that several sample preparation protocols required attention to maximize the fluorescence yields of the labeling dyes, such as thermal cycling conditions, choice of counter ion used for the ethanol precipitation step and also, dye-primer versus dye-terminator chemistries. In addition, several different sieving matrices were investigated for their effects on both the fluorescence properties of the labeling dyes and electrophoretic resolution. Extended times used for the high temperature denaturing of duplexed DNA fragments during cycle sequencing produced cleavage products, in which the covalently attached dye to the sequencing primer was released through attack by dithiothreitol (DTT). Even under optimized thermal cycling conditions, free dye was generated that masked readable data from the sequencing traces. Ethanol precipitation was necessary to remove this free dye with the proper choice of counter ion (sodium). The results using different sieving matrices indicated that linear polyacrylamides (LPAs) were appropriate for any fluorescence measurement, since they could readily be replaced between runs minimizing deleterious memory effects associated with cross-linked polyacrylamide gels. After investigation of several different sieving LPAs, the commercially available POP6 was found to be particularly attractive, since it produced good electrophoretic resolution, single exponential behavior for the near-IR dye series investigated herein, and also, discernible lifetime differences within the dye set. Finally, dye-terminator chemistry was also found to minimize bleeding in the gel matrix produced by large amounts of unextended dye-primer within the gel lane.     

粉末状半芳香尼龙PA12T的合成

以对苯二甲酸和1,12-十二碳二胺为原料,采用无水乙醇为溶剂,合成了粉末状的半芳香尼龙聚对苯二甲酰十二碳二胺(PA12T)。对影响PA12T聚合的各因素进行了分析研究,确定了合适的聚合工艺条件;利用红外光谱图(FT-IR)和核磁氢谱图(1H-NMR)对PA12T的结构进行了表征。该方法工艺简单,易于实现,适合工业化生产。     

Immobilized cibacron blue--leachables, support stability and toxicity on cultured cells

Although immobilized dyes are widely used on the laboratory scale and have good potential for industrial applications, they are still subject to some reservations. Little information is available about dye leakage and toxicity, which seriously hinders the use of such supports in the production of pure proteins. Investigations of the leakage mechanism and the in vitro toxicity of the native dye and of that leached from the column are reported. The possible presence of traces of dye in the purified biological materials necessitates the availability of sensitive analytical tests. The preparation and preliminary isolation of dye antibodies as a first step in the development of an immunohistochemical assay of leached dyes are also described.     

Application of artificial neural networks for formulation and modeling of dye adsorption onto multiwalled carbon nanotubes

In this study, an artificial neural network (ANN) has been developed to predict the adsorption amount of dye (methylene blue) onto multiwalled carbon nanotubes. Batch experiments have been carried out to obtain experimental data. Important parameters in the adsorption system such as initial dye concentration, adsorbent dosage, temperature, pH and contact time have been used as the inputs of the network, while the output is the final concentration of dye in aqueous solution after adsorption. The neural network structure has been optimized by testing various training algorithms and different number of neurons in a hidden layer. An empirical equation for determination of final dye concentration in aqueous solutions after adsorption has been developed by using the weights of the optimized network. The results of the optimized ANN have been compared with conventional models in equilibrium and kinetic fields. According to error analysis and determination coefficient, the ANN was found to be the most appropriate model to describe this adsorption process. Sensitivity analysis showed that initial dye concentration, pH and contact time are the most effective parameters in this process. The influence percentages of these parameters on the output were 28, 24 and 24 %, respectively.