Developent of cascade photo-bioreactor for the fixation of carbon dioxide

为了减少光源的能量损失，我们设计了带有反射器的新型反应器，并提出了将波长从绿色区域转移到红色区域以进行有效光合作用的荧光反射器。本研究考察了银质反射镜（5-Ref.）和荧光反射镜（F-Ref.）生物反应器对藻类光合速率的影响，并研究了荧光反射镜的光谱移位对藻类细胞的影响。在PET（聚对苯二甲酸乙二醇酯）基片上溅射银，并覆盖PET薄膜作为S-Ref。反射率(94%)。作为一个F-Ref。（59%反射率），荧光染料（Lumogen F-Red 300, BASF Japan Ltd.）涂在S-Ref上。黑色窗帘作为对照。测量采用同轴双管光生物反应器，反应器内有光源，外有藻类培养物（藻悬液光程为2.3 mm），用绿藻小球藻（Chlorella vulgaris）灌注培养物覆盖这些反射器。预培养3天后，将藻培养物灌注到光生物反应器中。氧气产量以光合速率来测量。作为荧光反射镜移谱对藻类细胞的影响，测定了8 d内的细胞浓度、细胞体积和吸收光谱。对照组在40W/m2照射下，虽然细胞浓度增加了5倍（=0.344g/l），但产氧速率只增加了1.7倍。但S-Ref。对照（细胞浓度= 0）02产量提高2.3倍。344 g/l)， F-Ref的2.0倍。所以这些反射器，尤其是S-Ref。更有效地利用能量。然而F-Ref。优于S-Ref。每反射光能产生1.7倍的氧气，其中F-Ref的光谱位移。对光合作用有效。虽然S-Ref的生长曲线。与S-Ref相似。16 h后细胞组成不同：S-Ref以母细胞为主；，子细胞在F-Ref中占主导地位。这些结果表明，红光加速了细胞的裂变，而小的子细胞（高的表面/体积比）也改善了生物反应器内的光照条件。少

we designed the new reactor with reflectors to reduce the energy loss of the light source and propose the fluorescent reflector that shifts wavelength from green region to red region for effective photosynthesis. In present study, we evaluated the effect of a bioreactor using silver reflector (5-Ref.) and fluorescent reflector (F-Ref.) on photosynthetic rates, and investigated the influence of spectral shifting by fluorescent reflector on algal cells.Base polyethylene terephthalate (PET) sheet was sputtered with silver and covered with PET film as a S-Ref. (94%Reflectivity). As a F-Ref. (59%Reflectivity), fluorescent dye (Lumogen F-Red 300, BASF Japan Ltd.) was coated on the S-Ref. A black curtain was used as control. Coaxial double tubular photobioreactors were used for measurements, which contain light sources inside and algal culture outside (light path of algal suspension is 2.3 mm) and were covered with these reflectors with perfusing culture of green algae Chlorella vulgaris IAM … More C-27. After preculture of 3 days, the algal culture were perfused in the photobioreactors. Oxygen production was measured as photosynthetic rates. As influence of spectral shifting by fluorescent reflector on algal cells, cell concentration, cell volume and absorption spectrum were measured during 8 days.At 40W/m2 irradiation in control, in spite of five-fold increase of cell concentration (=0.344g/l), O2 production rate rose only 1.7-fold. But S-Ref. rose 2.3-fold 02 production rate in control (cell concentration=O.344 g/l), and 2.0-fold in F-Ref. So these reflectors, especially S-Ref. Utilizes energy more efficiently. However F-Ref. was superior to S-Ref. with 1.7 times in O2 production rate per reflected light energy, in which the spectral shifting by F-Ref. is effective for photosynthesis. Although the growth curve of S-Ref. is similar to one of S-Ref., the composition of the cells after 16 hrs is different : mother cells are dominant in S-Ref., and daughter cells are dominant in F-Ref. These result imply that the red light accelerated the cell fission, and the small daughter cells (high surface / volume ratio) also improve the lighting condition in the bioreactor. Less