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51.
藉高锰酸钾氧化双乙酰的化学发光反应测定微量锰 总被引:10,自引:0,他引:10
研究了高锰酸钾氧化双乙酰的化学发光反应。根据微量Mn62+对上述体系化学发光山峰时间的影响,建立了测定Mn62+的分析方法。该法线性范围为1.0×10^-4-8.0×10^-67mol/L,相对标准偏差为3.5%,检出限为6.0×10^-8mol/L。应用于合金中锰的测定,结果良好。 相似文献
52.
A New Perylenequinone from Hypomyces sp. 总被引:4,自引:0,他引:4
Wei Zhong LIU* Yun Xiu SHEN Xiang Feng LIU Yuan Teng CHEN Jin Lun XIE Chemistry Teaching Research Department Binzhou Medical College Binzhou Fermentation Engineering Key Laboratory Yunnan University Kunming 《中国化学快报》2001,(5)
Some metabolites of fungi and plants containing perylenequinones have been used as folk medicine for the treatment of many diseases1,2. A filamentous fungus, Ascomy-cetes Hypocreaceae Hypomyces (Fr.) Tul. sp., was found from the northwestern mountains of Yunnan Province, and cultured successfully in the laboratory. A new perylenequinone, named hypomycin A (1), was isolated from its mycelia. In this paper the structure elucidation of 1 was described. Figure 1 The structure of compound 1 Fig… 相似文献
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The interaction between[Hg(SCN)4]2- and hemoglobin(Hb) under conditions that simulate a physiological environment was investigated by UV-vis spectroscopy,fluorescence spectroscopy,resonance Rayleigh scattering(RRS) spectroscopy and circular dichroism(CD) spectroscopy.The results obtained from the change of UV-vis and CD spectra,the quenching of Hb fluorescence and the enhancement of RRS intensity proved that a 10:1 type complex was formed between[Hg(SCN)4]2- and Hb.The possible mechanism suggested for the interaction was that ten Hg(SCN)4]2- anions entered the four subunits of a Hb molecule to react with some residues to form an adduct by coordination and electrostatic forces.The coordination of[Hg(SCN)4]2- with Trp was the major cause of the fluorescence quenching of Hb. 相似文献
55.
Wang L Chen H Wang L Wang G Li L Xu F 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2004,60(11):2469-2473
A novel composite nanoparticle has been prepared by an in situ polymerization method and applied as a protein fluorescence probe. The nano-CdS has been prepared, then the polymerization of acrylic acid (AA) was carried out by initiator potassium persulfate (KPS) under ultrasonic irradiation. The surface of the composite nanoparticles was covered with abundant carboxylic groups (--COOH). The nanoparticles are water-soluble, stable, and biocompatible. The synchronous fluorescence intensity of the composite nanoparticles is significantly increased in the presence of trace protein at pH 6.90. Based on this, a new synchronous fluorescence scan (SFS) analysis was developed for the determination of proteins including BSA, HSA, and human gamma-IgG. When Delta lambda = 280 nm, maximum synchronous fluorescence is produced at 290 nm. Under the optimum conditions, the response is linearly proportional to the concentration of proteins. The linear range is 0.1-10 microg ml(-1) for HSA, 0.09-8.0 microg ml(-1) for BSA, and 0.08-15 microg ml(-1) for human gamma-IgG, respectively. The method has been applied to the determination of the total protein in human serum samples collected from the hospital and the results are satisfactory. 相似文献
56.
以β-环糊精(β-CD)为手性添加剂,用毛细管区带电泳法对手性药物佐匹克隆进行了拆分研究.考察了β-环糊精浓度、背景电解质组成、浓度及pH值、分离电压、温度等对对映体分离的影响.结果表明,以pH 2.5的100 mmol/L三羟甲基氨基甲烷-磷酸溶液(含15 mmol/L β-环糊精)为运行缓冲液,分离电压28 kV,毛细管温度16 ℃,检测波长303 nm,佐匹克隆对映体达到最佳分离,分离度为2.7,对映体迁移时间分别为8.4、8.9 min.该方法简单、快速、经济,可适用于佐匹克隆对映体的手性分离. 相似文献
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The recently described pressure reaction in the presence of trithylamine with subsequent thermal (200°C) cyclization provided 13N‐pyridylcantharidinimides 4a‐4m from aminopyridines and cantharidin in yields of 15–83%. 2‐Amino‐3,5‐dichloropyridine failed to yield 4n . 相似文献
60.
Wan YS Chau JL Gavriilidis A Yeung KL 《Chemical communications (Cambridge, England)》2002,(8):878-879
A zeolite-based microengineered reactor was fabricated and tested for 1-pentene epoxidation over titanium silicalite-1 (TS-1) catalyst, which has been selectively incorporated within the microreactor channel using a new synthesis procedure. 相似文献