In this study, production of ct-linoleic acid concentrated from crude perilla oil by gradient cooling urea inclusion was optimized. The fatty acid composition was determined after ethyl esterification by gas chromatog...In this study, production of ct-linoleic acid concentrated from crude perilla oil by gradient cooling urea inclusion was optimized. The fatty acid composition was determined after ethyl esterification by gas chromatography （GC）. In this process, orthogonal experiment was carried out. Under optimum conditions, the maximum amount of α-linoleic acid （91.5%） was obtained at a urea to fatty acid ratio of 3, a solvent to fatty acids ratio of 7, a reaction temperature of 348 K and a crystallization time of 690 min. A simple method of gradient cooling urea inclusion was used to purify α-linolenic acid by using urea to form inclusion complexes with the saturated and the less unsaturated fatty acids, which enhanced the purity of α-linoleic acid ethyl ester by above 90%.展开更多
We report on fractal-featured square and ring-shaped apertures with a Sierpinski carpet pattern(SCP)on metallic and superconducting NbN films.Multiple extraordinary terahertz(THz)transmission peaks are studied in the ...We report on fractal-featured square and ring-shaped apertures with a Sierpinski carpet pattern(SCP)on metallic and superconducting NbN films.Multiple extraordinary terahertz(THz)transmission peaks are studied in the transmission spectra using both THz time-domain spectroscopy and numerical simulation.The characteristic transmission peaks are found to be associated with the interaction of surface plasmon polaritons(SPPs)and localized surface plasmons(LSPs)for ring-shaped apertures.The effect of LSPs is less remarkable in the square apertures.For the superconducting NbN film,when the temperature is slightly lower than the critical transition temperature T_(c),the peak magnitude of SPP resonances is most prominent due to the non-monotonic temperature dependence of kinetic inductance.These results provide a new way to design compact and efficient THz devices.展开更多
基金the National Natural Science Foundation of China (20871061)the National 973 Program of China (2008CB617512) for the financial support
文摘In this study, production of ct-linoleic acid concentrated from crude perilla oil by gradient cooling urea inclusion was optimized. The fatty acid composition was determined after ethyl esterification by gas chromatography （GC）. In this process, orthogonal experiment was carried out. Under optimum conditions, the maximum amount of α-linoleic acid （91.5%） was obtained at a urea to fatty acid ratio of 3, a solvent to fatty acids ratio of 7, a reaction temperature of 348 K and a crystallization time of 690 min. A simple method of gradient cooling urea inclusion was used to purify α-linolenic acid by using urea to form inclusion complexes with the saturated and the less unsaturated fatty acids, which enhanced the purity of α-linoleic acid ethyl ester by above 90%.
基金Supported by the National Basic Research Program of China(Nos 2011CBA00107,2011CBA00202)the National Natural Science Foundation of China under Grant Nos 61071009,61027008,11104110+1 种基金the Specialized Research Fund for Doctoral Program of Higher Education(20090091110040)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘We report on fractal-featured square and ring-shaped apertures with a Sierpinski carpet pattern(SCP)on metallic and superconducting NbN films.Multiple extraordinary terahertz(THz)transmission peaks are studied in the transmission spectra using both THz time-domain spectroscopy and numerical simulation.The characteristic transmission peaks are found to be associated with the interaction of surface plasmon polaritons(SPPs)and localized surface plasmons(LSPs)for ring-shaped apertures.The effect of LSPs is less remarkable in the square apertures.For the superconducting NbN film,when the temperature is slightly lower than the critical transition temperature T_(c),the peak magnitude of SPP resonances is most prominent due to the non-monotonic temperature dependence of kinetic inductance.These results provide a new way to design compact and efficient THz devices.
