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Anguo Ying Ming Zheng Haidan Xu Fangli Qiu Changhua Ge 《Research on Chemical Intermediates》2011,37(8):883-890
An efficient and facile protocol for aza-Michael addition of aliphatic and aromatic amines to electron-deficit alkenes using
[TMG][Lac] as catalyst under solvent-free conditions was established. 相似文献
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XU Songlin XIANG Aishuang & YING Anguo National Engineering Research Center for Distillation Technology School of Chemical Engineering Tianjin University Tianjin China 《中国科学B辑(英文版)》2004,47(6):521-527
3-hydroxypropionitrile (HPN) is widely used asmaterials in many organic reactions such as synthe-sizing medicine, pesticide and polymeric compound.Since the 1970s, HPN has mostly been synthesizedwith the reaction of acrylonitrile and H2O catalyzed byNaOH aqueous solution, and the mole yield of HPN isabove 85%. However, the HPN must be separatedfrom the acrylonitrile hydration mixture and get rid ofwater, salt and other side products. The traditional separation method is evapora-tion… 相似文献
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Thermo-responsive polymeric micelles of poly (ethylene glycol)-b-poly(2-hydroxyethyl methacrylate-g-lactide)-b-poly(N-isopropylacrylamide) (PEG-P(HEMA-PLA)-PNIPAM) with core–shell–corona structure were fabricated for applications in controlled drug release. The graft copolymer of PEG-P(HEMA-PLA)-PNIPAM was self-assembled into core–shell micelles with a densely PLA core and mixed PEG/PNIPAM shells at 25 °C in aqueous media. By increasing the temperature above the lower critical solution temperature of PNIPAM, these core–shell micelles could be converted into core–shell–corona micelles because of the collapse of PNIPAM block on the PLA core as the inner shell and the soluble PEG block stretching outside as the outer corona. Anticancer drug doxorubicin (DOX) was loaded in the polymeric micelles as a model drug. Compared with polymeric micelles formed by liner PEG-b-PLA-b-PNIPAM triblock copolymer, these polymeric micelles exhibited higher loading capacity, and release of DOX from the polymeric micelles with core–shell–corona structure was well-controlled. 相似文献
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制备了一种以三乙烯二胺(DABCO)为基础的离子液体;在水溶剂中,以该离子液体为催化剂催化三组分一锅法制备四氢苯并吡喃的反应,得到2-氨基-3-氰基-4-芳基-7,7-二甲基-5-氧代-4H-5,6,7,8-四氢苯并[b]吡喃;考察了反应时间、催化剂用量、催化剂加入时间、反应温度对反应收率的影响,确定了最优反应条件;由不同的芳香醛和活性亚甲基化合物制备了一系列四氢苯并吡喃衍生物,并讨论了可能的反应机理.结果表明,所选用的合成反应条件温和、时间短、收率高、后处理简单,且催化剂重复使用4次催化效果变化不大;就反应机理而言,所用催化剂具有双重催化活性. 相似文献
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Anguo Wu Tingting Duan Dan Tang Youhua Xu Liang Feng Zhaoguang Zheng Jiaxiao Zhu Rushang Wang Quan Zhu 《Chromatographia》2013,76(23-24):1649-1655
Nitrite and nitrate are main stable products of nitric oxide, a pivotal cellular signaling molecule, in biological fluids. Therefore, accurate measurement of the two ions is profoundly important. Nitrite is difficult to be determined for a larger number of interferences and unstable in the presence of oxygen. In this paper, a simple, cost-effective and accurate HPLC method for the determination of nitrite and nitrate was developed. On the basis of the reaction that nitrite is oxidized rapidly to nitrate with the addition of acidic potassium permanganate, the determination of nitrite and nitrate was achieved by the following strategy: each sample was injected twice for HPLC analysis, i.e. the first injection was to measure nitrate, and the second injection was to measure total nitrate including initial nitrate and the nitrate from the conversion of nitrite with the addition of acid potassium permanganate in the sample. The amount of nitrite can be calculated as difference between injections 2 and 1. The HPLC separation was performed on a reversed phase C18 column for 15 min. The mobile phase consisted of methanol–water (2:98 by volume); the water in the mobile phase contained 0.60 mM phosphate salt (potassium dihydrogen and disodium hydrogen phosphate) and 2.5 mM tetrabutylammonium perchlorate (TBAP). The UV wavelength was set at 210 nm. Additionally, we systemically investigated the effects of the concentration of phosphate salt and TBAP in the mobile phase, the pH of the mobile phase, and the amount of acidic potassium permanganate added to the sample on the separation efficacy. The results showed that the limits of detection (LOD) and the limit of quantitation (LOQ) were 0.075 and 0.25 μM for nitrate (containing the oxidized nitrite), respectively. The linear range was 1–800 μM. This developed approach was successfully applied to assay nitrite/nitrate levels in cell culture medium, cell lysate, rat plasma and urine. 相似文献
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Qinglong Song Anguo Liu Shimin Zhang Runxian Li Shiyan Qiao Pingli He 《Molecules (Basel, Switzerland)》2022,27(12)
Soybean glycinin, as a major soybean allergen, is difficult to accurately quantify due to its large molecular weight and complex structure. CdSe/ZnS quantum dot nanobead (QB) is a core/shell fluorescent nanomaterial with strong fluorescent signals and high sensitivity at 630 nm. An immunosorbent assay based on CdSe/ZnS quantum dot nanobeads (QBs-FLISA) was developed for the glycinin quantification in soybean and soybean products. Here, the purified glycinin was coated on the microporous plate to serve as the coating antigen, and CdSe/ZnS nanobead conjugated with anti-glycinin polyclonal antibodies was used as fluorescent detection probe. The target glycinin in the sample and the coated antigen on the plate competitively adsorbed the antibody labeled the CdSe/ZnS QBs probes. The limits of detection and quantitation for glycinin were 0.035 and 0.078 μg mL−1, respectively. The recoveries of the spiked samples ranged from 89.8% to 105.6%, with relative standard deviation less than 8.6%. However, compared with ELISA, the sensitivities of QBs-FLISA for the detection of glycinin were increased by 7 times, and the detection time was shortened by two-thirds. This QBs-FLISA method has been effectively applied to the detection of soybean seeds with different varieties and soy products with different processing techniques, which will provide a rapid screening method for soybean and soybean products with low allergens. 相似文献