Analysis and test of a wireless impedance-loaded SAW sensor

Micro & nano letters

article

Xifeng Zhu¹  Jianchun Xing¹  Liqiang Xie¹  Tianxian Wang¹ 

[1] College of Defense Engineering, Army Engineering University of PLA

关键词: surface acoustic wave sensors;    wireless sensor networks;    electric impedance measurement;    diffraction gratings;    surface acoustic wave sensor;    wireless passive measurement;    external impedance sensing element;    reflective grating;    resistance sensor;    capacitive sensor;    wireless transceiver system;    wireless impedance-loaded SAW sensor device;    COM modelling;    coupling-of-mode modelling;    lift-off process;    network analyser;   

DOI  :  10.1049/mnl.2018.5375

学科分类：计算机科学（综合）

来源: Wiley

【 摘 要 】

Ammi species belong to the family Umbellifereae that provide a host of bioactive compounds (mainly coumarins and flavonoids) of important biological activities, like prevention and treatment of heart and vascular disease and some types of cancer. Literature survey revealed that there was no study concerning Ammi flavonoids in Iraq. Ammi majus and Ammi visnaga, which are wildly grown in Iraq, were chosen for this study. This study concerned with extraction, identification, isolation, and purification of some biologically important flavonols quercetin and kaempferol from the fruits of Ammi majus and Ammi visnaga. Extraction of these flavonols was carried out using 85% methanol and 90% ethanol. Identification of these flavonols quercetin and kaempferol was done using thin Layer chromatography (TLC) where different solvent systems had been tried. Ultra violet (UV) Light and iodine vapor where used for detection. This identification was further augmented by using high performance Liquid chromatography (HPLC) and then these flavonols were isolated and purified. The most suitable extraction, isolation and purification procedures of flavonols were fully described in this study. The identification of isolated flavonols (quercetin & kaempferol) was carried out using melting point (M.P.), Thin Layer chromatography (TLC), and infrared spectroscopy (IR).This study confirms the presence of quercetin and kaempferol in Ammi majus & an Ammi visnaga fruit, the percentage of quercetin was higher in Ammi visnaga than Ammi majus, while the percentage of kaempferol was higher in Ammi majus than Ammi visnaga.

【 授权许可】

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