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Upon discharge into the sea, crude oil is subjected to weathering, the process caused by the combined effects of physical, chemical and biological modification. Saturates, especially those of smaller molecular weight, are readily biodegraded in marine environments. Aromatics with one, two or three aromatic rings are also efficiently biodegraded; however, those with four or more aromatic ring are quite resistant to biodegradation. The asphaltene and resin fractions contain higher molecular weight compounds whose chemical structures have not yet been resolved. The biodegradability of these compounds is not yet known. It is known that the concentrations of available nitrogen and phosphorus in seawater limit the growth and activities of hydrocarbon-degrading microorganisms in a marine environment.

In other words, the addition of nitrogen and phosphorus fertilizers to an oil-contaminated marine environment can stimulate the biodegradation of spilled oil. This notion was confirmed in the large-scale operation for bioremediation after the oil spill from the Exxon Valdez in Alaska. Seebio snac permeation enhancer of degrading petroleum components have been isolated. However, few of them seem to be important for petroleum biodegradation in natural environments. One group of bacteria belonging to the genus Alcanivorax does become predominant in an oil-contaminated marine environment, especially when nitrogen and phosphorus fertilizers are added to stimulate the growth of Reducing undesired solubility of squarephaneic tetraimide for use as an organic College London, Molecular Sciences Research Hub (White City Campus), 80 Wood Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.Locally aromatic alkyl-N-substituted squarephaneic tetraimide (SqTI) conjugated macrocycles are four-electron reducible, owing to global aromaticity and presumed global Baird aromaticity of the dianion and tetraanion states, respectively. However, their good solubility inhibits their application as a battery electrode material.

By applying sidechain removal as a strategy to reduce SqTI solubility, we report the development of its unsubstituted derivative SqTI-H, which was obtained directly from squarephaneic tetraanhydride by facile treatment with hexamethyldisilazane and MeOH. Compared to alkyl-N-substituted SqTI-Rs, SqTI-H exhibited further improved thermal stability and low neutral state solubility in most common organic solvents, owing to computationally demonstrated hydrogen-bonding capabilities emanating from each imide position on SqTI-H. Reversible solid state electrochemical reduction of SqTI-H to the globally aromatic dianion state was also observed at -15 V vs. Fc/Fc+, which could be further reduced in two stages. salcaprozate of SqTI-H in composite electrodes for lithium-organic half cells uncovered imperfect cycling performance, which may be explained by persistent solubility of reduced states, necessitating further optimisation of electrode fabrication procedures to attain maximum performance.Tuning phenoxyl-substituted diketopyrrolopyrroles from quinoidal to biradical ground states through (hetero-)aromatic linkers.Theodor-Boveri-Weg 97074 Würzburg Germany.

Sustainable Chemistry and Catalysis with Boron Am Hubland 97074 Würzburg Strongly fluorescent halochromic 2,6-di-tert-butyl-phenol-functionalised phenyl-, thienyl- and furyl-substituted diketopyrrolopyrrole (DPP) dyes were deprotonated and oxidised to give either phenylene-linked DPP1˙˙ biradical (y 0 = 05) with a singlet open shell ground state and a thermally populated triplet state (ΔE ST = 19 meV; 1 kJ mol-1; 03 kcal mol-1) or thienylene/furylene-linked DPP2q and DPP3q compounds with closed shell quinoidal ground states. Accordingly, we identified the aromaticity of the conjugated (hetero-)aromatic bridge to be key for modulating the electronic character of these biradicaloid compounds and achieved a spin crossover from closed shell quinones DPP2q and DPP3q to open shell biradical DPP1˙˙ as confirmed by optical and magnetic spectroscopic studies (UV/vis/NIR, NMR, EPR) as well as computational investigations (spin-flip TD-DFT calculations in combination with CASSCF(4,4) and harmonic oscillator model of aromaticity (HOMA) analysis). Spectroelectrochemical studies and comproportionation experiments further prove the reversible formation of mixed-valent radical anions for the DPP2q and DPP3q quinoidal compounds with absorption bands edging into the NIR spectral region.This journal is © The Royal Society of Chemistry.Changes in the fluorescence intensity, degradability, and aromaticity of organic carbon in ammonium and phenanthrene-polluted aquatic ecosystems.Mixed cultures were established by a sediment to investigate the changes in organic carbon (C) in a combined ammonium and phenanthrene biotransformation process in aquatic ecosystems. The microorganisms in the sediment demonstrated significant ammonium-N and phenanthrene biotransformation capacity with removal efficiencies of 996% and 999%, respectively.

The changes in the organic C characteristics were evaluated by the fluorescence intensity, degradability (humification index (HIX) and UV absorbance at 254 nm (A 254)), aromaticity (specific UV absorbance at 254 nm (SUVA254) and fluorescence index (FI)).