手性胺拆分法制备雷美替胺

以(S)-苯乙胺为拆分剂,对合成雷美替胺(1)的中间体(R,S)-2-{1,6,7,8-四氢-2H-茚并[5,4-b]呋喃-8-基}乙酸[(R,S)-2]进行拆分得(S)-2;(S)-2再经3步反应合成了(S)-1,ee值为97%。以L-(-)-二苯甲酰酒石酸为拆分剂,对(R,S)-2-{1,6,7,8-四氢-2H-茚并[5,4-b]呋喃-8-基}乙胺[(R,S)-3]进行拆分得(S)-3;(S)-3再经1步反应合成了(S)-1,ee值为99%。1的结构经1H NMR确证。     

提纯溶剂对室温合成CsPbBr3量子点性能的影响

采用室温重结晶法制备CsPbBr_3量子点,分别利用六种常用的极性溶剂对量子点粗液进行高速离心提纯,监测提纯过程中每一步骤后的光致发光光谱,并采用吸收光谱,荧光寿命、X射线衍射分析和透射电镜等表征方法系统表征了六种极性溶剂提纯得到的CsPbBr_3量子点.研究表明,通过六种极性溶剂提纯,都可以得到结晶度良好的呈立方体形态的立方相CsPbBr_3量子点;在利用六种不同极性溶剂进行提纯过程中,第二次离心得到的上清液具有最为统一的半峰宽和峰值波长;除乙酸乙酯外,第二次离心得到的上清液具有最高的量子产出;比较而言,通过正丙醇、异丙醇、正丁醇特别是异丁醇提纯得到的CsPbBr_3量子点具有较高的发光性能.     

罗丹明B纯度标准物质的研制

以商购罗丹明B为原料,进行重结晶提纯,制备罗丹明B纯度标准物质。采用红外光谱(IR)、高分辨质谱和核磁共振谱(NMR)进行定性分析。样品分装400瓶后,依据国家《一级标准物质研制技术规范》,采用液相色谱-二极管阵列法对随机抽取的15瓶样品进行均匀性检验,经F检验表明,在95%的置信区间范围内,样品均匀性良好。在室温下,经过30个月稳定性考察,结果表明样品稳定性良好。标准物质经国内8家具有分析资质的实验室进行协同定值,定值结果为99.0%,扩展不确定度为1.0%(k=2)。该标准物质达到了国家标准物质的技术要求,可用于有关罗丹明B的分析方法校正和质量控制。     

纯C60的非色谱法分离

介绍三类实用的非色谱分离纯化Ｃ６０的新方法，它们具有简便、分离量大、费用低等特点。将有助于国内Ｃ６０研究的广泛开发。     

重结晶中一种简便的热过滤方法

重结晶是提纯固体有机化合物的一种常用方法。在重结晶操作过程中,关键步骤之一是热过滤。传统的热过滤方法是借助于布氏漏斗或玻璃漏斗进行的。操作时,首先要将布氏漏斗或玻璃漏斗预热,以防热过滤时,晶体过早析出,有时甚至还要附上保温套。尽管如此,当溶剂容易挥发,特别是当待结晶物质的溶解度随温度变化很大时,热过滤操作仍会遇到麻     

槐米中芦丁提取、精制与鉴定的创新实验教学

In order to solve the frequently encountered problems on the experiment of extraction, refining and identification of Rutin in the laboratory class, new methods of teaching design and experiment process were adopted to suit different experimental procedure. With the improvement, both the success rate and the students' confidence were improved. The innovation experiment also illustrated the importance of process improvement to improve the quality of the products. Through the mutual improvement of teaching and learning in this experiment, teachers and students achieved the goal of learning together.     

THE EFFECT OF EC ON ORIENTATION AND RELAXATION OF PP OBTAINED VIA DYNAMIC PACKING INJECTION MOLDING

As a long term project aiming at engineering plastics based on polypropylene (PP), in this work, we report the effect of ethylene-cellulose (EC) on the orientation and relaxation of PP obtained via dynamic packing injection molding (DPIM). 2d-WAXD results showed that PP with a highly oriented structure and a shish-kebab structure were achieved by DIPM, leading to an increase of tensile strength from 35.0MPa to 48.6MPa. The degree of orientation of PP was increased by adding only 1% of EC, resulting in a further increase of tensile strength from 48.6MPa to 53.8MPa. Shish was found to exist not only in the oriented layer but also in the core of the sample after adding EC, as evidenced by DSC result.This was understood as due to the overall decrease of viscosity by the addition of EC, thus an increasing of shear rate. Higher shear rate can favor the orientation of molecules and continuous growth of shish structure, resulting in a change of shish distribution along the sample thickness. On the other hand, the relaxation mode of shish in the melt recrystallization of PP is also greatly affected by the presence of EC. A retarded relaxation of PP macromolecules was seen.Even more, SEM results showed that EC could form the short fibers in PP matrix along the shear flow direction. Compared with the morphology obtained by conventional injection molding, a much better dispersion and easy break-up of EC in PP matrix were observed for samples obtained by dynamic packing injection molding.     

连翘红茶中连翘脂素的提取方法研究

以连翘红茶为原料,对其提取分离连翘脂素方法进行研究。以连翘脂素的质量浓度作为指标,采用超高压液相色谱进行分析检测,比较不同柱材料和重结晶条件对连翘脂素的分离纯化能力。最佳方法:利用75%乙醇回流提取,水洗两次,D101大孔吸附树脂70%洗脱7BV,重结晶四次,四道工序七步操作即可得到了纯度98%的连翘脂素,总收率49%。整个提取分离方法具有得到的连翘脂素纯度高,回收率高,不使用易燃有毒的有机溶剂,对设备的要求低,操作步骤少且简单,大孔吸附树脂可重复多次使用等特点。     

氨基酸修饰环糊精的合成及表征

环糊精衍生物;氨基酸;合成;葡聚糖凝胶;重结晶     

用有机溶剂提纯六氟磷酸锂粗品

本文用乙醚作为纯化溶剂,采用有机溶剂重结晶并辅以洗涤萃取等方法来提纯六氟磷酸锂(LiPF6)粗品。工艺操作条件温和、能耗低、原材料无毒无HF腐蚀、简便易得,是一条绿色工艺纯化路线。经红外光谱、X射线粉末衍射对提纯后的晶体LiPF6进行结构确认和物相分析,对最终产品LiPF6中氯离子(Cl-)、乙二醇二甲醚(DME)不溶物和乙醚残留量进行检测分析,还探讨了残留的乙醚对锂离子二次电池首次充放电性能的影响。结果表明:LiPF6粗品经乙醚提纯后纯度达到99.98%,优于商用LiPF6;产品中微量乙醚残留不会对锂离子二次电池首次充放电性能造成不良影响。