Addressing Practical Use of Viologen-Derivatives in Redox Flow Batteries through Molecular Engineering.

In practical scenarios, viologen-derivatives face an accelerated degradation in the unavoidable presence of traces of oxygen in large-scale redox flow batteries. Herein, we confirm the primary degradation mechanism and propose a straightforward, cheap, and fast method to evaluate the stability of viologen-derivatives toward this degradation. Considering that the cleavage of the N-substituent is the main proposed pathway for viologen degradation, a new viologen-derivative, bearing an alkylsulfonate chain with a secondary carbon center joined to the N atom, is synthesized to illustrate how molecular engineering can be used to improve stability.

Types and Distribution of Bioactive Polyunsaturated Aldehydes in a Gradient from Mesotrophic to Oligotrophic Waters in the Alborán Sea (Western Mediterranean).

Polyunsaturated aldehydes (PUAs) are bioactive molecules suggested as chemical defenses and infochemicals. In marine coastal habitats, diatoms reach high PUA production levels during bloom episodes. Two fractions of PUA can usually be analyzed: pPUA obtained via artificial breakage of collected phytoplankton cells and dissolved PUA already released to the environment (dPUA).

Annual variations of total and fractionated chlorophyll and phytoplankton groups in the Gulf of Cadiz.

Chlorophyll and phytoplankton distribution and concentration in the Gulf of Cadiz were studied during 2014 and 2015. In both years the highest chlorophyll concentrations are found at coastal stations during spring. Pico- and nanophytoplankton are the main contributors to total chlorophyll, with highest concentrations at the outer limit of the continental shelf.

Effects of TiO nanoparticles and sunscreens on coastal marine microalgae: Ultraviolet radiation is key variable for toxicity assessment.

Given the large numbers of sunbathers on beaches, sunscreen compounds are being released into the coastal aquatic environment in significant amounts. Until now the effect of these potential pollutants on microbiota has been not well-known. Phytoplankton is a key component of the microbiota community.

Changes in membrane lipids and carotenoids during light acclimation in a marine cyanobacterium Synechococcus sp.

Time course of carotenoid and membrane lipid variation during high light (HL) acclimation (about 85 meu mol m-2 s-1), after transfer from low light (LL) (5-10 meu mol m-2 s-1), was determined in a marine Synechococcus strain. Highperformance liquid chromatography (HPLC) coupled to diode array detector (DAD) or electrospray ionization mass spectrometry (ESI-MS) was used for compound separation and detection. Myxoxanthophyll rose within a time interval of 8 h to 24 h after the onset of exposure to HL.