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Considering the instability and toxicity of 3D Pb-based perovskite nanocrystals, lead-free low-dimensional organic–inorganic hybrid metal halides have attracted widespread attention as potential substitutes. Herein, two new tin-based 0D halides [H4BAPP]SnBr5·Br and [H4BAPP]SnCl5·Cl·H2O (BAPP = 1,4-bis(3-aminopropyl)piperazine) were synthesized successfully based on [SnX5]3− as an emission center. Typically, [H4BAPP]SnBr5·Br and [H4BAPP]SnCl5·Cl·H2O display broadband yellow and yellow-green light emissions originating from the radiative recombination of self-trapped excitons (STEs). The photoluminescence quantum yields (PLQYs) of the two compounds were calculated to be 19.27% and 2.36%, respectively. Furthermore, the excellent chemical and thermal stability and broadband light emissions reveal their potential application in solid-state white lighting diodes. [ABSTRACT FROM AUTHOR]

BACKGROUND In recent years, mixotrophic culture of algal cells has been gaining increasing interest, largely because it offers an efficient means of commercial production of lipids and other value‐added products. In this work, the impacts of glucose addition on the biomass production, chemical composition and fatty acid profiles of Chlorella kessleri were investigated to exploit the relationships between extra organic carbon and changes in the distribution of chemical compositions in algal cells. RESULTS: Results showed that C. kessleri grew fast in the mixotrophic cultures with a maximum algal biomass and specific growth rate of 4.46 g L−1 and 1.27 day−1, respectively. Glucose in the cultures was absorbed and utilized effectively by this alga, whose uptake efficiencies ranged from 88.2% to 98.3%, but it had a negative impact on the synthesis of photosynthetic pigments. Additionally, the culture's pH and chemical composition, including pigments, carbohydrate, protein and lipids, in this alga varied with the change of glucose concentrations in the cultures. The fatty acid profiles of this alga indicated that its biomass could be used as live feeds in aquaculture or a good‐quality feedstock for biodiesel production. CONCLUSIONS: These results suggested that adding an extra organic carbon source (glucose) to a photoautotrophic culture was a potentially effective way to improve the performance in mixotrophically culture of microalgae, for example in terms of higher biomass and lipid production. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In this work, a cultivation system with daily recycling of the post-harvest culture broth was set up and performed in order to reuse the water and nutrients in pretreated anaerobically digested swine manure, which was used as media to cultivate Chlorella vulgaris (UTEX 2714) at different recycling ratios. Results showed that the alga grew well in the system with an accumulative algal biomass and productivity of 1.68–3.47 g/L and 234.1–532.2 mg/L/d, respectively, at the end of the cultivation. Additionally, chemical compositions in this alga varied with the change of recycling ratios, and the highest productivities of carbohydrate, protein and lipids (76.4, 257.2 and 183.7 mg/L/d, respectively) were obtained in the system with a recycling ratio of 1/4 or 1/6. Fatty acid profiles indicated that this alga could be used as a good-quality biodiesel feedstock with a biodiesel productivity of 9.65–40.1 mg/L/d. [ABSTRACT FROM AUTHOR]

Ionic liquids (ILs) have been considered as “green” substitutes for traditional organic solvents in many existing biological and chemical areas. However, they have high solubility and poor biodegradability in water, suggesting that they could become persistent chemical pollutants in aquatic environment. The ability of two widely used imidazolium-based ILs to affect the growth and physiological characteristics of a marine diatom ( Phaeodactylum tricornutum ) was investigated in this study. The diatom was exposed to different concentrations of 1-butyl-3-methylimidazolium tetrafluoroborate ([C 4 mim]BF 4 ) and 1-octyl-3-methylimidazolium tetrafluoroborate ([C 8 mim]BF 4 ) for 96 h within a batch-culture system. Results showed that [C 4 mim]BF 4 and [C 8 mim]BF 4 were very stable in seawater during 96 h of exposure, and the compounds significantly inhibited the growth of P. tricornutum with 24, 48, 72 and 96 h EC 50 values of 30.81, 28.53, 39.92, 45.88 mg L −1 and 30.17, 23.36, 28.62, 31.37 mg L −1 , respectively. In addition, the photosynthetic activity and chlorophyll a synthesis of P. tricornutum were inhibited by [C 4 mim]BF 4 and [C 8 mim]BF 4 , indicating that the structural integrity of chloroplasts of the diatom may be disrupted or damaged by the two ILs. Compared with that of the controls, reactive oxygen species (ROS) level was increased by 0.65, 1.17, 1.85, 3.13, 2.94 times and 0.55, 1.77, 2.42, 3.45, 3.47 times in 5, 10, 20, 40 and 60 mg L −1 [C 4 mim]BF 4 and [C 8 mim]BF 4 treatments, respectively. The excessive ROS may cause lipid peroxidation, shortage of metabolic energy and decline of photosynthetic efficiency, which may be the main reason for toxicity of the two ILs to marine diatoms. To withstand the damaging effects of excessive ROS, remarkable physiological and biochemical responses occurred in treatments with the two ILs to protect the cells of P. tricornutum . Parameters such as soluble protein content, soluble sugar content, and superoxide dismutase (SOD) and peroxidase (POD) activities of the diatom increased significantly with increasing concentrations of the two ILs at 96 h of exposure relative to the controls. These findings not only provide strong background for evaluating the ecological risks and toxicity of ILs in marine environment, but also help to unravel the toxic mechanism of the two ILs to marine diatoms. [ABSTRACT FROM AUTHOR]

Considering the instability and toxicity of 3D Pb-based perovskite nanocrystals, lead-free low-dimensional organic-inorganic hybrid metal halides have attracted widespread attention as potential substitutes. Herein, two new tin-based 0D halides [H 4 BAPP]SnBr 5 ·Br and [H 4 BAPP]SnCl 5 ·Cl·H 2 O (BAPP = 1,4-bis(3-aminopropyl)piperazine) were synthesized successfully based on [SnX 5 ] 3- as an emission center. Typically, [H 4 BAPP]SnBr 5 ·Br and [H 4 BAPP]SnCl 5 ·Cl·H 2 O display broadband yellow and yellow-green light emissions originating from the radiative recombination of self-trapped excitons (STEs). The photoluminescence quantum yields (PLQYs) of the two compounds were calculated to be 19.27% and 2.36%, respectively. Furthermore, the excellent chemical and thermal stability and broadband light emissions reveal their potential application in solid-state white lighting diodes.

Recently, some researchers have pointed out that the threats of ionic liquids (ILs) to aquatic environment cannot be ignored. Thus, this study investigated the potential toxicity of 1-dodecyl-3-methylimidazolium tetrafluoroborate ([C 12 mim]BF 4 ) on a marine diatom Phaeodactylum tricornutum at population, biochemical and physiological levels using 96h growth tests with a batch-culture system. Results showed that [C 12 mim]BF 4 was very stable in aquatic environment during 96h of exposure. The growth of P. tricornutum was significantly inhibited by [C 12 mim]BF 4 with 24, 48, 72 and 96h EC 50 values of 0.63, 0.61, 0.68 and 0.72mgL -1 , respectively. Although there were no significant differences between the controls and treatments with 0.1 and 0.5mgL -1 [C 12 mim]BF 4 , the effective quantum yields (Φ PSII ) of the diatom in 1, 2.5, 5 and 10mgL -1 [C 12 mim]BF 4 treatments were 61.48, 17.04, 2.96 and 0.74% of that in the controls at 96h of exposure, respectively. Chl a content of the diatom was decreased by 34.86, 47.79, 49.81, 59.21, 79.82 and 86.98% compared with that of the controls at 96h of exposure in 0.1, 0.5, 1, 2.5, 5 and 10mgL -1 [C 12 mim]BF 4 treatments, respectively. Relative to the controls, soluble sugar content, reactive oxygen species (ROS) level, malondialdehyde (MDA) content, superoxide dismutase (SOD) and peroxidase (POD) activities of the diatom increased with increasing [C 12 mim]BF 4 concentrations at 96h of exposure, and reached their maxima (1.46μg10 6 cell -1 , 7.48FU10 7 cell -1 , 3.35nmol10 8 cell -1 , 33.41 and 7.23Umg -1 proteins, respectively) in 5mgL -1 [C 12 mim]BF 4 treatments. While the maximum soluble protein content (1.56μg10 6 cell -1 ) of the diatom was obtained in 0.5mgL -1 [C 12 mim]BF 4 treatments, and then decreased with increasing [C 12 mim]BF 4 concentrations from 0.5 to 10mgL -1 . These findings provide strong evidence for the potential toxicity of ILs to marine diatoms., (Copyright © 2017 Elsevier B.V. All rights reserved.)

It is very important to have a good understanding of the biological effects of nanoparticles (NPs) on marine diatoms. In this study, the physiological and biochemical responses of a marine diatom Phaeodactylum tricornutum to titanium dioxide NPs (nano-TiO 2 ) and cerium oxide NPs (nano-CeO 2 ) were compared and evaluated using 96h growth tests in a batch-culture system. At 96h of exposure, the growth inhibition rate (IR, %) of P. tricornutum increased from 5.46 to 27.31% with increasing nano-TiO 2 concentrations from 2.5 to 40mgL -1 . The maximum IR of 49.59% occurred in 40mgL -1 nano-TiO 2 treatments at 48h of exposure. Growth of the diatom was increased in low nano-CeO 2 treatments (≤5mgL -1 ), but was inhibited in high nano-CeO 2 treatments (≥10mgL -1 ). Large aggregates of NPs were attached to the cells of P. tricornutum in 20 and 40mgL -1 nano-TiO 2 and nano-CeO 2 treatments. In addition, the effective quantum yields (Φ PSII ) of P. tricornutum in 40mgL -1 nano-TiO 2 and nano-CeO 2 treatments were 83.33 and 71.13% of that in the controls at 96h of exposure, respectively. Compared with that of the controls at 96h of exposure, chlorophyll a content, soluble sugar content, malondialdehyde (MDA) content, SOD and POD activities of P. tricornutum in 40mgL -1 nano-TiO 2 and nano-CeO 2 treatments increased by 57.56, 142.97, 373.25, 698.76, 204.85% and 21.43, 89.41, 194.97, 340.05, 502.86%, while soluble protein content decreased by 70.38 and 28.64%, respectively. These findings will be helpful to understand the effect mechanisms of NPs on marine organisms., (Copyright © 2016 Elsevier B.V. All rights reserved.)