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11.
火焰原子吸收光谱法测定鱼腥草、西洋参和茯苓中的铜含量 总被引:1,自引:0,他引:1
用硝酸-高氯酸混合酸(4∶1)消化鱼腥草、西洋参和茯苓,在波长324.8nm处,利用火焰原子吸收光谱法测定鱼腥草、西洋参和茯苓中铜的含量。线性回归方程为A=0.1708C 0.0004,相关系数r=0.9997,线性范围为0—5μg/mL,检出限为0.0035μg/mL,测定结果的相对标准偏差为0.09%,加标回收率为98.0%—104.2%。 相似文献
12.
Mkhalid IA Coapes RB Edes SN Coventry DN Souza FE Thomas RL Hall JJ Bi SW Lin Z Marder TB 《Dalton transactions (Cambridge, England : 2003)》2008,(8):1055-1064
We present herein a high yield, highly selective catalytic synthesis of vinylboronate esters (VBEs), including 1,1-disubstituted VBEs, from alkenes without significant hydrogenation or hydroboration, using the simple catalyst precursor, trans-[RhCl(CO)(PPh3)2] (1), and the diboron reagents B2pin2 (2a, pin = pinacolato = OCMe2CMe2O) or B2neop2 (2b, neop = neopentylglycolato = OCH2CMe2CH2O), or the monoboron reagent HBpin, all of which are commercially available. The reactions were conducted at 80 degrees C using conventional heating, or in a microwave reactor at 150 degrees C. 相似文献
13.
Sheta M. Sheta Said M. El‐Sheikh Mohkles M. Abd‐Elzaher Salem R. Salem Hanan A. Moussa Reda M. Mohamed Ibraheem A. Mkhalid 《应用有机金属化学》2019,33(12)
For the first time, alpha‐fetoprotein (AFP) quantification as an early test for liver cancer diagnosis competing with other interfering analytes and factors based on a novel nano‐magnetic metal–organic framework (MOF) was investigated. The novel nano‐magnetic MOF was synthesized via a simple preparation method, and characterized using various techniques. The X‐ray photoelectron spectrum of the nano‐magnetic MOF shows Cu 2p, O 1s, N 1s and C 1s peaks that evidence the presence of these elements in the sample without any impurities. Scanning and transmission electron microscopy images show the nano‐magnetic MOF with average size between 22 and 43 nm. The results of a photoluminescence study show that the nano‐magnetic MOF exhibits strong emission at 418 nm after excitation at 354 nm. Moreover, a Stern–Völmer graph shows a linear calibration curve over an AFP concentration range 1.0–520 ng ml?1 with a correlation coefficient of 0.997, detection limit of 1.18 ng ml?1 and quantitation limit of 3.58 ng ml?1. According to the marked quenching of the photoluminescence intensity of the nano‐magnetic MOF using various concentrations of AFP, it was successfully used as a biosensor for AFP in serum samples collected from hepatitis patients in addition to healthy males and females. The quenching mechanism was well studied, and found to be a dynamic type. The present work offers a simple, low‐cost, room‐temperature and rapid technique, being non‐time‐consuming, highly accurate, selective and highly sensitive compared with most published methods. 相似文献