微藻光谱衰减特性测量的一种改进方法  

An improved method for determining optical extinction characteristics of microalgae

作　　者：李兴灿[1] 赵军明[1] 刘林华[1] 张琳[2] LI XingCan ZHAO JunMing LIU LinHua ZHANG Lin(School of Energy Science and Engineering, Harbin Institute of Technology, Harbin 150001, China College of Mechanical and Electrical Engineering, Northeast Forestry University, Harbin 150040, China)

机构地区：[1]哈尔滨工业大学能源科学与工程学院,哈尔滨150001 [2]东北林业大学机电学院,哈尔滨150040

出　　处：《科学通报》2017年第4期328-334,共7页Chinese Science Bulletin

基　　金：国家自然科学基金(51336002;51276051;51421063;51306030)资助

摘　　要：给出了一种可更准确测量微藻混悬液及微藻细胞光谱衰减特性的改进方法,该方法利用不同藻液光程的两个比色皿进行测试,充分考虑了多层介质间的多次反射作用.利用改进的双光程法测得蒸馏水的光谱衰减系数与文献中的数据吻合较好.实验结果表明在300~700 nm波段,BG11培养基的光谱衰减系数显著高于蒸馏水,而大于700 nm波段时,其光谱衰减系数与蒸馏水基本相同.在300~1300 nm波段,小球藻混悬液的光谱衰减系数随波长变化明显且随着浓度的增大而增大,而在1300~1800 nm波段时,浓度对其的影响减弱.在测量波段,不同浓度小球藻的衰减系数及衰减截面随着波长增大逐渐减小,且不同浓度小球藻衰减截面非常接近.The urgent demand to replace traditional fossil fuels has led to emergence of biofuels as feasible alternatives. Microalgae are considered to be one promising alternative source for biofuels. Light is regarded as one of the most vital factors which affecting the photosynthetic activity. Photobioreactors are used for cultivating microalgae which absorb light as energy source for their growth. The productivity of photobioreactors are confined by light transfer. The kinetic and mathematical models for microalgal photosynthesis or growth need accurate information about light attenuation and distribution in microalgal suspensions. An improved transmission method is proposed to obtain the spectral extinction characteristics of microalgae suspensions and cells in the paper. The light attenuation in the cell mixture suspensions is considered from the combined contributions of the culture medium and the microalgae. In measuring, the microalgae suspensions are considered to be well mixed. In this method, the optical constants of the glass（cuvette） are obtained at the first step. Then, the spectral extinction coefficient of the microalgae suspensions is retrieved using the two measured normal-normal transmittance based on a rigourous theoretical model considering multiple reflections and refractions at air-glass and glass-liquid interfaces. The improved method is demonstrated to provide good results of spectral extinction characteristics over the studied spectral range 300–1800 nm. The trend of the refractive index spectra of BG11 medium and distilled water are similar, which decreases from about 1.39 to 1.32 with the increasing wavelength. The absorption coefficient between culture medium and distilled water show significant difference in the spectral range 300–700 nm while exhibit small difference in the wavelength range 700–1800 nm. The difference is attributed to the different composition between culture medium and distilled water. The effective refractive index of Chlorellasp. suspensions varies little with i

关 键 词：双光程法 微藻 衰减系数 衰减截面 

分 类 号：Q947[生物学—植物学]