欢迎您！东篱公司
退出
-
申报数据库
-
立项数据库
-
成果数据库
-
项目获奖数据库
中文摘要：
开发了一种新型廉价紫外荧光光源，采用中波透紫玻璃作为灯管，灯管玻璃本身可以吸收254nm以下的紫外光，因此反应器不需要滤光液。得到了光照时间与麦角固醇转化率及前维生素D2选择性得率之间的关系。初步研究了该光源紫外光强度随时间的衰减变化，并对光强衰减与光化学反应结果的影响进行了研究。结果表明，该廉价光源在65min可以使反应达到65．5％的转化率，选择性得率为60．4％，且光源强度在300h内仅衰减13％。该光源成本较低，寿命较长，且反应器不需要滤光液，设备投资较少，是一种理想的可用于工业化生产的廉价光源。
英文摘要：
Vitamin D2, also called ergocalciferol, has important effect on adjusting the in vivo metabolize of calcium and phosphorus. Vitamin D2 is manufactured by irradiation of ergosterol（E）. Many studies have been done on the reaction, showing that UV irradiation of ergosterol produces many isomers ： vitamin D2, pre-vitamin D2 （P） , tachysterol, lumisterol and that the best irradiation wavelength is in the range of 270 - 310 nm for the conversion from ergosterol to pre-vitamin D2, which is not photochemically but thermally isomerized into vitamin D2. The purpose of this paper is to find a new light source with a better result for the photoreaction with a low cost. The tube glass of the lamp could absorb most of the spectrum range below 254 nm which gives more by-products, so there was not any filter solution used. Firstly a certain amount of ergosterol was dissolved in ethanol to make a reactant solution （1.0 mg/mL）. This solution was put in the photochemical reaction apparatus and irradiated by low pressure Hg lamp. The reactant solution samples taken at different time were put in brown bottles, blown off ethanol with nitrogen gas. The dry sample was stored in refrigerator and was dissolved with n-heptane for liquid chromatography analysis. The intensity of the lamp was also measured at intervals. Through experiments, not only the relation between the transformation rates of photoreaction, but also the time of irradiation were studied. The decay curve of the light intensity within 300 h was also obtained. The result is that, the conversion ratio of the ergosterol was 65.5% in 65 min, and the selectivity of pre-vitamin D2 was 60.4%. The decay of the light intensity was only 13% in 300 h. Not any filter solution was needed in the photochemical reaction, this could decrease the whole cost in factory. And most important thing is that this lamp is very cheap, which shows a quite satisfying potential prospect for the industrialisation of vitamin D2.
同期刊论文项目
同项目期刊论文
期刊信息
位置：