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BACKGROUND Tubular photobioreactors are considered to be important and potential photobioreactors due to their higher photosynthetic efficiency and biomass productivity. In this work the performance of a new tubular photobioreactor with novel static mixers on mixing characteristics and light regime was studied through computational fluid dynamics. RESULTS The effects of cross-angle of two blades, horizontal spacing, open porosity and hole radius of the novel static mixers on mixing characteristics were investigated to obtain appropriate configurations. Compared with the tubular photobioreactor without static mixers, the tubular photobioreactor with novel static mixers was proved to have strong fluid mixing and significant swirling flow. Average velocity magnitude along the light direction increased by nearly 1000 times and turbulent kinetic energy increased by 1.3 times after adding novel static mixers into the tubular photobioreactor. Additionally, with novel static mixers most cells were promoted to circulate between the light zone and the dark zone. The light/dark cycle frequency was also improved and increased by 85.21% and 95.77% at fluid inlet velocity of 0.3 and 0.4 m s−1, respectively. CONCLUSION The simulation results showed the novel static mixers could effectively enhance mixing degree of fluid and increase the light/dark cycle frequency of microalgal cells in tubular photobioreactors. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Two strong photoluminescence (PL) bands in the spectral range of 550–900 nm have been observed at room temperature from a series of a-SiO x :H films fabricated by plasma-enhanced chemical vapor deposition (PECVD) technique. One is composed of a main band in the red-light region and a shoulder; the other is located at about 850 nm, only found after 1170°C annealing in N2 atmosphere. In conjunction with infrared (IR) and micro-Raman spectra, it is thought that the two PL bands are associated with a-Si clusters in the SiO x network and nanocrystalline silicon in SiO2, respectively. [ABSTRACT FROM AUTHOR]

BACKGROUND Different responses to identical trauma may be related to the genetic background of individuals, but the molecular mechanism is unclear. In this study we investigated the heterogeneity of trauma in mice and the potential biological explanations for the differences. MATERIAL AND METHODS Compared with other organs, the pathological response of the lung after injury is the earliest and most serious. We used C57BL/6 and BALB/C mice to explore the genetic background of different responses to trauma in the lung. We measured mortality rate, pulmonary microvascular permeability, and Cxcl15 gene expression in BALB/C and C57BL/6 mice before and after blast-wave injury. Microvascular permeability was measured using a fluorescent tracer, and Cxcl15 gene expression level and expression distribution were measured using fluorogenic probe quantitative polymerase chain reaction and northern blot. RESULTS C57BL/6 mice showed lower mortality rates and pulmonary microvascular permeability than BALB/C mice after blast-wave injury; there was no significant difference in the permeability before blast-wave injury. The Cxcl15 gene was expressed specifically in the lung tissue of mice. The level of Cxcl15 expression in BALB/C mice was higher than in C57BL/6 mice before and after injury, and the variation trend of Cxcl15 expression level after injury was significantly different between BALB/C and C57BL/6 mice. CONCLUSIONS Our results indicated that BALB/C and C57BL/6 mice had significant heterogeneity in posttraumatic response in terms of mortality and degree of lung damage. The differences in genetic factors such as Cxcl15 may have played a role in this heterogeneity.