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41.
Seven polystyrene-type adsorbents (Ⅰ—Ⅶ) were synthesized by the modification of styrene-divinylbenzene copolymer respectively with hydroxymethyl, aminomethyl, methoxymethyl, phenoxymethyl, (4-hydroxy phenoxy)methyl, (4-acetylphenoxy)methyl, and acetyl groups. Their structures were characterized with chemical methods and physical techniques. The adsorption capacities of the adsorbents to stevioside and gypenosides were determined via batch test in which the HPLC method was used for the analysis of Saponin concentration of solution. The results showed that all the adsorbents could adsorb these saponins to a certain extent, but Ⅵ and Ⅶ had large capacities owing to their moderate polarities. 相似文献
42.
43.
主链含膦酸酯的聚酸酐药物控制释放材料研究 总被引:1,自引:0,他引:1
通过二氯膦甲(乙)酸乙酯与对羟乙氧基苯甲酸反应,制备了二羧苯氧乙氧基膦甲(乙)酸乙酯,并其转化成混合醋酐并通过熔融缩聚,合成了主链含膦甲(乙)酸乙酯的聚酸酐,以二羧苯氧乙氧基膦甲(乙)酸乙酯,分别与1,3-双(4-羧基苯氧基)丙烷(CPP)及癸二酸(SA)共聚,得到相应的共聚酸酐,对所合成的单体和聚合物的结构进行了表征,研究了它们的体外降解,酶促降解及其对抗肿瘤药物5-氟尿嘧啶和氨甲喋蛉的释放性能 相似文献
44.
XiaoFAN NianJunXU JianGongSHI 《中国化学快报》2003,14(10):1045-1047
A new brominated phenylpropylaldehyde and its dimethyl acetal together with a new natural brominated phenol were isolated from Rhodomela confervoides. Their structrues were elucidated as 2-methyl-3-(2,3-dibromo-4,5-dihydroxyphenyl)propylaldehyde, 2-methyl-3-(2,3-di-bromo-4,5-dihydroxyphenyl) propylaldehyde dimethyl acetal and 3-bromo-4,5-dihydroxybenzoic acid methyl ester by spectroscopic techniques including IR, HRFABMS, 1D and 2DNMR experiments. 相似文献
45.
XinYingZHANG XueSenFAN JianJiWANG YanZhenLI 《中国化学快报》2004,15(10):1170-1172
Quinoline derivatives were efficiently prepared through acid-catalyzed Friedlander reaction in ionic liquid ([bmim] [BF4]). It is shown that the proposed method is operationally simple and environmentally benign in that the reaction media and the catalyst can be recovered and be reused effectively for at least four times. 相似文献
46.
DFT Study on the (S)-Proline-catalyzed Direct Aldol Reaction between Acetone and 4-Nitrobenzaldehyde
1 INTRODUCTION Aldol reaction, one of the most important C–C bond-formation reactions, is widely utilized in orga- nic synthesis[1]. Extensive efforts have been donated to the development of catalytic stereo-selective va- riants of this reaction[2]. However, the direct aldol reaction between unmodified carbonyles would be the most attractive synthetic alternative. Proline-catalyzed intermolecular direct aldol reac- tion between acetone and 4-nitrobenzaldehyde was first reported by List… 相似文献
47.
维生素B12缺乏致神经损害临床分析 总被引:2,自引:0,他引:2
维生素B12缺乏多继发于胃肠道外科手术后、贫血及其它内科疾病,其引起的神经系统损害临床表现多样,主要为周围神经损害及亚急性联合变性。测定维生素B1:值、查肌电图等可明确诊断。补充维生素B12治疗有效。 相似文献
48.
以互通多孔碳(IPC)为载体,水热条件下在碳表面原位反应生成纳米结构的二氧化锰(MnO2),制备互通多孔碳/二氧化锰纳米(IPC/MnO2)复合电极材料. 采用扫描电镜(SEM),透射电镜(TEM),X射线衍射(XRD),热重分析(TGA)对其结构进行表征;采用循环伏安法、恒流充放电和交流阻抗对其电化学性能进行研究. 结果表明:生成的MnO2均匀地负载在碳的表面,形成多层次结构,并且随着温度的升高IPC表面负载的MnO2由纳米颗粒变为纳米片状结构;MnO2纳米片具有典型的K-Birnessite 型晶体结构;复合物中MnO2的含量约为34%(w). 在100 ℃制备的IPC/MnO2复合材料在三电极系统中最高比电容达到了411 F·g-1;随着反应温度的升高,比容量先增长后基本保持不变. 以IPC/MnO2为正极,活性炭(AC)为负极,1 mol·L-1 Na2SO4溶液为电解液组装成IPC/MnO2//AC 混合超级电容器,发现IPC/MnO2电极的电容器其电位窗口从1 V扩展到1.8 V,容量可达86F·g-1,且表现出良好的电容特性和大电流放电性能. 相似文献
49.
A novel coordination polymer {[Zn(ts-gln)(bipy)]3H2O}n (ts-glnH2=N-p-toly-sulfonyl-glutamine,bipy=2,2-bipyridine) has been prepared and structurally characterized by X-ray diffraction method. It crystallizes in orthorhombic,space group P212121 with a=8.2622(5),b=16.6244(10),c=18.2807(10) ,V=2510.9(3) 3,C22H28N4O8SZn,Mr=573.91,Z=4,Dc= 1.518 g/cm3,μ(MoKa)=1.115 mm-1,F(000)=1192,the final R=0.0262 and wR=0.0662 for 5691 independent reflections with Rint=0.0240. The zinc(Ⅱ) atom is coordinated by N(3) and N(4) atoms of a bipy molecule,two carboxylate O(1) and O(2A) and amino N(1) atoms of ts-gln ligands,resulting in a square-pyramidal geometry. The title complex consists of an infinite zigzag chain of zinc(Ⅱ) ions linked by the carboxylate of N-p-tolysulfonyl-glutamine. 相似文献
50.
一个新的噻二唑衍生物H2ADTZ与锰的二维聚合物的合成与晶体结构(英) 总被引:2,自引:0,他引:2
A new 1,3,4 thiadiazole-derivative ligand 2,5-(s-acetic acid) dimercapto-1,3,4 thiadiazole (H2ADTZ) and its one-dimensional manganese polymer Mn(ADTZ)·4H2O had been synthesized and structurally characterized by X-ray single crystal diffraction in this paper. The Mn(Ⅱ) ion is coordinated with a distorted octahedron by two oxygen atoms from neighboring two deprotonated ligands ADTZ2- and other four oxygen atoms from four coordinated water molecules. The structural feature of the title compound is the formation of one-dimensional manganese chains polymer through the bridging of dioxygen O-O units. In the solid state structure of the complex, one-dimensional manganese chains are joined together by the weak intermolecular hydrogen bonds and vander Waals interactions forming a two-dimensional supramolecular compound. Furthermore, the UV spectra and electro-chemical properties of the title compound were also investigated. CCDC: 260532. 相似文献