Spectroscopic-ellipsometry measurement of the optical properties of zinc oxide thin films prepared by sol–gel method: coating speed effect

Micro & nano letters

article

Maryam Motallebi Aghgonbad¹  Hassan Sedghi¹ 

[1] Department of Physics, Faculty of Science, Urmia University

关键词: zinc compounds;    II-VI semiconductors;    wide band gap semiconductors;    semiconductor thin films;    spin coating;    sol-gel processing;    ellipsometry;    refractive index;    extinction coefficients;    ultraviolet spectra;    visible spectra;    infrared spectra;    dielectric function;    absorption coefficients;    energy gap;    Kramers-Kronig relations;    voids (solid);    semiconductor growth;    spectroscopic-ellipsometry measurement;    optical properties;    zinc oxide thin films;    sol-gel spin coating method;    coating speed effect;    optical constants;    refractive index;    extinction coefficient;    dielectric function;    absorption coefficient;    optical bandgap energy;    incidence angle;    computer programming;    Kramers-Kronig relations;    high transmittance;    visible region;    void fraction;    wavelength 300 nm to 800 nm;    ZnO;   

DOI  :  10.1049/mnl.2017.0882

学科分类：计算机科学（综合）

来源: Wiley

【 摘 要 】

Abstract   The objective of this study was to investigate the phytochemical constituents of two different parts of Vigna radiata (seeds and sprouts), and identify their  anti angiogenic activity .the goal was achieved by Preliminary qualitative phytochemical screening for crude ethanolic extract of two parts of plant  ; rat aorta anti-angiogenesis assay had been conducted for both extracts .   isolation , separation and purification of some phytochemical constituents that belong to important groups (flavonoids) from  n-butanol fraction extract of Vigna radiata plant had been done in pure form by using preparative thin layer chromatography ( PTLC ) and then subjected to different spectral  analytical and physicochemical  techniques to identify their chemical structure : melting point ( M. P) , thin layer chromatography ( TLC ) high performance liquid chromatography ( HPLC ) , Fourier transforms infrared spectra ( FTIR ) . and high performance thin layer chromatography ( HPTLC ).the result  showed that  the existence of coumarin , alkaloids, phenols, flavonoids , terpenoids, phytosterol and saponin.Vitexin and isovitexin  were isolated in pure form .n-butanol fraction of sprouts  showed highest percentage of blood vessels inhibition ( 88%) in comparison to n-butanol fraction of seeds which showed (56%). There IC50 were 58.8µg/ml and 56.6 µg/ml respectively. The difference of anti angiogenic activity may be  related to the variation of concentration of the bioactive constituents or appearance of new bioactive constituents during germination.

【 授权许可】

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