N-乙基咔唑-3-甲醛席夫碱荧光探针的合成及其检测Cu2+性质

以咔唑为原料,经过两步反应制备得到N-乙基咔唑-3-甲醛,其结构经X射线单晶衍射测定属于单斜晶系,空间群为P2₁/n。再以N-乙基咔唑-3-甲醛与1,3-二氨-2-丙醇为原料,设计、合成了一种新型双席夫碱荧光探针分子CMP。借助荧光光谱在体积比为6∶4的DMSO/H₂O缓冲溶液(Tris-HCl,pH=7.0)中研究了探针CMP对Cu²⁺的选择性识别。研究结果表明,探针CMP与Cu²⁺以1∶2的比例配位,结合常数为1.52×10⁵ L·mol^-1,检出限为0.205 μmol·L^-1。回收实验表明,探针分子CMP可应用于环境水样中Cu²⁺的检测。     

新中国化学题材邮票及其在化学教育中的应用

新中国化学题材邮票是化学史的重要文献和化学教育的可用资源。在对新中国化学题材邮票进行界定、分类及内容解读的基础上,阐述了化学题材邮票在化学史专题教育、教材插图、课堂教学和高考试题编制中的应用价值,并对化学题材邮票的发行和后续应用提出建议。     

国学在高校有机化学教学中的应用

探讨了在有机化学的实际教学中，采用国学中的诗词歌赋、情境设置、风俗习惯、人文礼教等独特的教学手段，使学生能够在轻松愉悦的氛围下自主学习，并达到永久性记忆的学习效果，为高等学校教育方法提供一定的参考。     

典型燃料点火延迟时间的一阶和二阶局部和全局敏感度分析

Sensitivity analysis is an important tool in model validation and evaluation that has been employed extensively in the analysis of chemical kinetic models of combustion processes. The input parameters of a chemical kinetic model are always associated with some uncertainties, and the effects of these uncertainties on the predicted combustion properties can be determined through sensitivity analysis. In this work, first- and second-order global and local sensitivity coefficients of ignition delay time with respect to the scaling factor for reaction rate constants in chemical kinetic mechanisms for combustion of H₂, methane, n-butane, and n-heptane are examined. In the sensitivity analysis performed here, the output of the model is taken to be natural logarithm of ignition delay time and the input parameters are the natural logarithms of the factors that scale the reaction rate constants. The output of the model is expressed as a polynomial function of the input parameters, with up to coupling between two input parameters in the present sensitivity analysis. This polynomial function is determined by varying one or two input parameters, and allows the determination of both local and global sensitivity coefficients. The order of the polynomial function in the present work is four, and the factor that scales the reaction rate constant is in the range from 1/e to e, where e is the base of the natural logarithm. A relatively small number of sample runs are required in this approach compared to the global sensitivity analysis based on the highly dimensional model representation method, which utilizes random sampling of input (RS-HDMR). In RS-HDMR, sensitivity coefficients are determined only for the rate constants of a limited number of reactions; the present approach, by contrast, affords sensitivity coefficients for a larger number of reactions. Reactions and reaction pairs with the largest sensitivity coefficients are listed for ignition delay times of four typical fuels. Global sensitivity coefficients are always positive, while local sensitivity coefficients can be either positive or negative. A negative local sensitivity coefficient indicates that the reaction promotes ignition, while a positive local sensitivity coefficient suggests that the reaction actually suppresses ignition. Our results show that important reactions or reaction pairs identified by global sensitivity analysis are usually rather similar to those based on local sensitivity analysis. This finding can probably be attributed to the fact that the values of input parameters are within a rather small range in the sensitivity analysis, and nonlinear effects for such a small range of parameters are negligible. It is possible to determine global sensitivity coefficients by varying the input parameters over a larger range using the present approach. Such analysis shows that correlation effects between an important reaction and a minor reaction can have relatively sizable second-order sensitivity coefficient in some cases. On the other hand, first-order global sensitivity coefficients in the present approach will be affected by coupling between two reactions, and some results of the first-order global sensitivity analysis will be different from those determined by local sensitivity analysis or global sensitivity analysis under conditions where the correlation effects of two reactions are neglected. The present sensitivity analysis approach provides valuable information on important reactions as well as correlated effects of two reactions on the combustion characteristics of a chemical kinetic mechanism. In addition, the analysis can also be employed to aid global sensitivity analysis using RS-HDMR, where global sensitivity coefficients are determined more reliably.     

纳米银颗粒通过血脑屏障中剂量-效应关系的初步研究

目的:本文研究了纳米银颗粒通过血脑屏障的剂量-效应关系,并对其通过血脑屏障的机理进行了初步推测。方法:研究中先建立了一个体外血脑屏障模型,再以纳米银颗粒为试验样品、微米银颗粒为对照样品,将不同浓度(25~400μg.mL-1)的试样和对照样加入体外血脑屏障模型中共同培养4 h,之后利用ICP-MS测定通过血脑屏障的银颗粒百分比,并采用TEM观察BBB细胞的超微结构。结果:在相同剂量下,只有纳米银颗粒能通过血脑屏障;当纳米银颗粒的剂量小于100μg.mL-1时,血脑屏障结构完整,有约2%纳米银颗粒通过血脑屏障;当纳米银颗粒剂量在100~400μg.mL-1的范围内时,随纳米银颗粒剂量增加,纳米银颗粒通过血脑屏障的比率也会相应增加,而且血脑屏障结构被破坏的程度也相应增加。纳米银颗粒剂量为400μg.mL-1时,有约15%的纳米银颗粒通过了血脑屏障。结论:初步推断,在剂量较低时,纳米银颗粒主要通过"细胞转运机理"通过血脑屏障,当剂量大到足以对脑毛细血管内皮细胞产生足够的细胞毒性时,"细胞毒性机理"将起主要作用。这也提示我们,即使剂量很小,纳米银颗粒仍能通过血脑屏障。因此在使用含有纳米银颗粒的医用产品甚至保健品时应持谨慎的态度。     

苯甲酰苯并咪唑衍生物的合成

以3,5-二甲基-1H-吡咯-2-甲酸乙酯(2)为起始原料,与新型Vilsmeier试剂反应得4-甲酰基-3,5-二甲基-1H-吡咯-2-甲酸乙酯(3);3与3,4-二氨基二苯甲酮环合制得4-(5-苯甲酰-1H-苯并咪唑-2-基)-3,5-二甲基-1H-吡咯-2-甲酸乙酯(4);4水解后与2-吡唑啉经脱水反应合成了一个苯并咪唑衍生物,总收率54%,其结构经1H NMR,13C NMR和MS确证。     

蜂王浆冻干粉中甲硝唑残留标准样品制备的研究

建立了蜂王浆冻干粉中甲硝唑残留标准样品的研制和定值方法。对日常检测阳性样品进行匀浆、冷冻干燥和均匀化加工处理,真空包装,得到1批400袋蜂王浆冻干粉样本。F检验法和t检验法表明在95%置信区间内,样本均匀性、短期稳定性和长期稳定性均达到标准样品要求。制备的甲硝唑标准样品采用液相色谱-串联质谱法,与国内外8家实验室进行协同定值。采用格拉布斯和柯克伦检验对定值结果进行异常值检验,并对结果进行不确定度评估。     

Bi/TiO2复合纳米纤维制备及可见光催化性能

以电纺TiO₂纳米纤维为基质,EDTA为鳌合剂和吸附剂,采用溶剂热法制备Bi/TiO₂复合纳米纤维光催化材料,利用X射线粉末衍射（XRD）、扫描电镜（SEM）、X射线能量色散谱（EDS）、透射电镜（TEM）、紫外-可见漫反射光谱（UV-Vis DRS）和荧光光谱（PL）等分析测试手段对样品的物相、形貌和光学性能等进行表征,以罗丹明B（RhB）为模拟有机污染物,考察了样品的光催化性能。结果表明：EDTA在复合纳米纤维的合成过程中起到关键作用,通过改变EDTA的用量可以有效控制纤维表面构筑单质Bi纳米球的大小和覆盖密度。所制备的复合纳米纤维具有良好的可见光催化活性和稳定性,当单质Bi的负载量为65%时光催化活性最强,可见光照射180 min,RhB的降解率达到96.40%,循环使用5次降解率仍保持在91%以上。     

N-二异丙基磷酰基-N-[2-(3',4'-亚甲二氧苯基)]乙基甘氨酸的单昌结构的研究

三类杉酯碱是一种具有显著抗肿瘤活性的化合物, 在以磷脱基, 磺酰基乙酰基作N-苯乙基甘氨酸上氨基的保护基进行分子内酰化的Friede-Crafts反应, 合成三尖杉酯碱母核-(N-7,8-亚甲二氧苯并-3-氮杂环庚酮-1)时所得结果相差甚远, 特别是用磷酰基保护甘氨酸衍生物可以避免脱羰, 顺利地进行内酰化反应, 对合成三尖杉酯碱的母核有重要的意义。为了阐明磷酰基对氨基酸中氮原子上的弧对电子的稳定作用, 我们测定了N-二异丙基磷酰基-N-[2-(3',4'-亚甲二氧苯基)]乙基甘氨酸的单晶结构。     

NiP/SAPO-11催化脂肪酸甲酯加氢脱氧及产物的异构化

采用过量浸渍法制备了不同镍负载量的Ni P/SAPO-11催化剂,并用N2吸附-脱附、吡啶红外光谱、NH3-TPD、H2-TPR等技术对催化剂的物理化学性能进行了测试。脂肪酸甲酯催化加氢脱氧及产物异构化反应在固定床反应器上进行,液体产品分别用GC-MS和GC进行定性和定量分析。结果表明,在温度为340℃,压力为2.0 MPa,氢气流量为60 m L/min,重时空速为2.5 h-1的操作条件下,当Ni负载量为3%(质量分数)时,原料转化率可以达到97.8%,C15-18的收率84.5%,异构化率14.0%。