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Ioannis N. Pasias Eleni G. Farmaki Nikolaos S. Τhomaidis Efrosini A. Piperaki 《Food Analytical Methods》2010,3(3):195-204
The determination of 18 elements (V, Cr, Cu, Co, Se, Sr, Sn, Sb, Ba, Bi, Pb, Cd, As, Ni, Mn, Fe, Mg and Zn) in leaves, flowers
and the infusion from Salvia fruticosa, a sage grown in Greece, is described. For this purpose, flame atomic absorption spectrometry has been used for the determination
of Fe, Mg, Zn and inductively coupled plasma-mass spectrometry has been used for the determination of V, Cr, Cu, Co, Se, Sr,
Sn, Sb, Ba, Bi, Pb, Cd, As, Ni, Mn using 45Sc 72Ge, 115In and 232Th as internal standards. The elemental content was found to be in the range of 0.01 (Bi)-30.8 (Mn) mg/Kg (leaves), 0.30 (Bi)-39.1
(Mn) mg/Kg (flowers), 0.003 (Sb)-20.4 (Mn) mg/Kg (infusion) for V, Cr, Cu, Co, Se, Sr, Sn, Sb, Ba, Bi, Pb, Cd, As, Ni, Mn
and in the range of 0.07 (Zn)-3.21 (Mg) g/kg (leaves) for Fe, Mg and Zn. The majority of the samples were collected from six
sites in the island Crete and transplanted and grown in a model farm. Chemometric techniques were used to investigate the
original site classification according to their elemental content, and it was proved that the initial cultivation sites were
characterized by only five elements (Sb, V, Zn, Cd and Cr). The application of factor analysis revealed significant correlation
between certain elements, denoting their common sources. In addition, the total antioxidant activity of the herbal preparation
was determined by measuring the 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity. Microwave-assisted extraction (MAE)
was used to extract total antioxidants and the effect of temperature, time and solvent in the extraction efficiency was investigated.
The determination of the antioxidant activity was based on the % inhibition of the absorbance signal of the radical DPPH at
515 nm, after the addition of herbal’s extract. The IC50 values were found to be in the range of 10.6–40.1 mg/L. 相似文献
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NIE Hui- wen��ZHOU Jia- lin��LAI Chun- ming����CHEN Hua- qiang ZHU Zhao- shun 《钢铁研究学报》2015,27(9):57-62
通过合理的化学成分以及冶炼、连铸和轧制工艺的设计与控制,开发了一种硫系易切削钢C1118,并进行了工艺实践,成功生产了28mm的圆钢。通过金相显微镜、扫描电镜、能谱仪和Leica图像仪对其组织、夹杂物进行了观察分析,结果表明:该工艺下生产的易切削圆钢疏松等级良好,基体组织为铁素体和少量的珠光体,MnS以长条状或纺锤状存在,可以细化铁素体组织并改善钢的切削性能。开发的易切削钢C1118的力学性能满足供货要求,切削性能优异,磨损速度明显低于45号钢,相对于45号钢的加工性Kr为1.62。 相似文献
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