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51.
FAAS测定十味平性活血化淤中药中Fe、Cu、Zn、Mn的含量 总被引:1,自引:0,他引:1
为揭示中药药性本质,用FAAS测定并比较了十味平性活血化淤中药中微量元素Fe、Cu、Zn和Mn的含量。结果表明,十味活血化淤中药均含有Fe、Cu、Zn、Mn等4种元素,其中Fe、Cu、Zn、Mn的含量范围分别为0.0416~1.2977,0.0025—0.0297,0.2100~0.1501,0.0071~0.7380μg·g^-1。方法加标回收率为98.7%~100.5%,RSD≤2.45%(n=6)。实验方法简便可行,测定结果准确可靠,为后续研究提供了基础数据。 相似文献
52.
AbstractTwo biomaterials based on the abundant Bulgarian medicinal plants Mentha spicata L. (denoted as MS) and Ruta graveolens L. (denoted as RG) were investigated as environmentally friendly biosorbents for Cu(II) removal from aqueous solutions. Grain size distribution, slurry pH, texture parameters, thermal behavior and mineralogical composition of MS and RG were determined. Instrumental methods such as scanning electron microscopy (SEM), X-ray-diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, Brunauer–Emmett–Teller (BET) analysis, differential thermal analysis (DTA), and thermogravimetric analysis (TGA) were used for their characterization. It was demonstrated that the surface morphology of both materials is rough and contains pores that could entrap different pollutants, as well as functional groups that can attach metal ions. In order to examine the feasibility of these materials for use as biosorbents for heavy metals, adsorption experiments were performed. The results for the removal of Cu(II) ions from aqueous solution reveal capabilities suggesting that both materials have potential to be used as promising, efficient and low-cost biosorbents. 相似文献
53.
Two new dibenzofurans,7,8-dimethoxy-4-methyldibenzofuran-1-carboxaldehyde, named ligumedial (1) and 7,8-dimethoxy-4-methyldibenzofuran-1-carboxylic acid, named ligumediaoic acid (2), have been isolated from the underground parts of Ligularia intermedia. Their structures were elucidated by spectroscopic methods. 相似文献
54.
Determination of hydroxyl radical by capillary electrophoresis and studies on hydroxyl radical scavenging activities of Chinese herbs 总被引:5,自引:0,他引:5
High-performance capillary electrophoresis (CE) with electrochemical detection (ED) was employed to determine hydroxyl radicals in the Fenton reaction. Hydroxyl radicals can react with salicylic acid to produce 2,3-dihydroxy benzoic acid and 2,5-dihydroxy benzoic acid, which can be analyzed by CE-ED. Based on this principle, hydroxyl radicals were determined indirectly. In a 20 mmol/L phosphate running buffer (pH 7.4), 2,3-dihydroxy benzoic acid and 2,5-dihydroxy benzoic acid would elute simultaneously from the capillary within 6 min. As the working electrode, a 300 m diameter carbon-disk electrode exhibits good responses at +0.60 V (vs. SCE) for the two analytes. Peak currents of the two analytes are additive. Excellent linearity was obtained in the concentration range from 1.0×10-3 mol/L to 5.0×10-6 mol/L for 2,3-dihydroxy benzoic acid. The detection limit (S/N=3) was 2.0×10-6 mol/L. This method was successfully applied for studying hydroxyl radical scavenging activities of Chinese herbs. It is testified that Apocynum Venetum L., Jinkgo bibola L., Morus alba L. and Rhododendron dauricum L. have strong hydroxyl radical scavenging activities. 相似文献
55.
Nonaqueous CE (NACE) coupled to UV detection is described for the separation and determination of bioactive flavone derivatives in Chinese herbs extraction. After optimization of electrophoresis parameters, including the electrolyte nature and the organic solvent composition, a reliable separation of the analytes in an ACN/methanol (60:40, v/v) mixture containing 80 mM Tris and 10 mM sodium cholate was performed. The detection was performed at 254 nm. Method performances, including migration time and peak area reproducibility, linearity, sensitivity, and accuracy, were evaluated. The method was applied to determine bioactive flavone derivatives in seven Chinese herbs. 相似文献
56.
二阶导数光谱峰面积法测定中草药中微量锗 总被引:4,自引:0,他引:4
在Ge 苯基荧光酮 (PF) 氯化十六烷基吡啶 (CPC)三元络合物的显色体系中 ,引入二阶导数光谱峰面积技术 ,对锗的显色体系及测定方法进行了研究。该方法有效地消除了W 、Sn 、Mo 、V 、Ti 和Fe(Ⅲ )等离子的干扰 ,提高了准确度和选择性。线性范围为 0~ 1 5mg L,检出限为 3 .3 μg L ,εGe为 1 .4× 1 0 5L·mol- 1 ·cm- 1 。用于中药材中Ge 的测定 ,标准加入试验的回收率为 1 0 1 .0 %~ 1 1 2 .0 %。 相似文献
57.
58.
活血化瘀中药中无机元素含量测定 总被引:2,自引:0,他引:2
采用原子吸收分光光度法测定了丹参、红花草、益母草等活血化瘀中草药中多种无机元素的含量。结果表明,这些中草药中含有多种直接参与组织代谢的微量元素。 相似文献
59.
60.
氢化物发生-原子荧光光谱法测定中药材中汞和砷 总被引:10,自引:0,他引:10
用氢化物发生-原子荧光光谱法测定了产于海南省的5种中药材,即槟榔、益智、砂仁、巴戟天及沉香中汞含量及砷含量.对试样的预处理和消解方法以及仪器的工作条件作了详述,还对各种对测定有影响的因素,包括试样消解所用的酸的种类及其浓度,硼氢化钾的加入浓度,五价砷的预还原和共存金属离子的干扰等也作了研究并予以优化选择.方法的检出限分别为1.5 ng·g-1(汞)和7.0 ng·g-1(砷).在对5种药材的实样进行分析的基础上作了回收率试验,所得结果为90%~93%(汞)和90%~91%(砷). 相似文献