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Understanding nano-bio interactions is pivotal to the safe implementation of nanotechnology for both biological and environmental applications. Zebrafish as a model organism provides unique opportunities to dissect nano-bio interactions occurring at different biological barriers. In this review, we focus on four key biological barriers, namely cell membrane, blood-brain barrier (BBB), skin and gill epithelia, and gastrointestinal tract (GIT), and highlight recent advancement achieved by using zebrafish to conduct both visualized observations and mechanistic investigations on a diversity of nano-bio interactions.Amine groups are among the most effective systems for carbon dioxide capture. Reminiscent of the activation of nature’s most abundant enzyme RuBisCO, the treatment of amines with CO2 in the presence of oxophilic metal ions, e.g. Mg2+, results in the formation of carbamates. Here we report the synthesis, structure and magnetic properties of three new dysprosium-carbamato complexes. The reaction of gaseous CO2 with N,N-diisopropylamine and DyCl3(DME)2 (DME = Dimethoxyethane) in toluene leads to the formation of the tetrametallic complex [Dy4(O2CNiPr2)10(O-C2H4-OMe)2]. The addition of 2-hydroxy-3-methoxybenzaldehyde-N-methylimine yields the hexametallic compound [Dy6(O2CNiPr2)8(O-C2H4-OMe)2(CO3)2(C9O2NH10)4] in which the metal sites form a chair-like configuration; The same hexanuclear motif is obtained using N,N-dibenzylamine. We show that by employing CO2 as a feedstock, we are able to capture up to 2.5 molecules of CO2 per Dy ion. Magnetic measurements show a decreasing χMT at low temperatures. Combining the experimental magnetic data with ab initio calculations reveils tilting of the easy axes and implies the presence of antiferromagnetic interactions between the Dy(iii) metal ions.The surface structure and reaction pathways of 7-octenoic acid are studied on a clean copper substrate in ultrahigh vacuum using a combination of reflection-absorption infrared spectroscopy, X-ray photoelectron spectroscopy, temperature-programmed desorption and scanning-tunneling microscopy, supplemented by first-principles density functional theory calculations. 7-Octenoic acid adsorbs molecularly on copper below ∼260 K in a flat-lying configuration at low coverages, becoming more upright as the coverage increases. It deprotonates following adsorption at ∼300 K to form an η2-7-octenoate species. This also lies flat at low coverages, but forms a more vertical self-assembled monolayer as the coverage increases. Heating causes the 7-octenoate species to start to tilt, which produces a small amount of carbon dioxide at ∼550 K and some hydrogen in a peak at ∼615 K ascribed to the reaction of these tilted species. The majority of the decarbonylation occurs at ∼650 K when CO2 and hydrogen evolve simultaneously. Approximately half of the carbon is deposited on the surface as oligomeric species that undergo further dehydrogenation to evolve more hydrogen at ∼740 K. This leaves a carbonaceous layer on the surface, which contains hexagonal motifs connoting the onset of graphitization of the surface.It is generally accepted that autocatalysis is a kinetic phenomenon, where a product of a reacting system functions as a catalyst. Consequently, the reaction proceeds faster upon adding the corresponding product to the unreacted mixture of reactants providing an unequivocal possibility of how a system may be identified either experimentally or theoretically as an autocatalysis. Once this is approved, it often results in sigmoidal concentration-time profiles, though it is neither a necessary nor sufficient prerequisite because appropriate mechanistic and parametric conditions must be met to give rise to the appearance of this kinetic feature. Several mass action type kinetic models producing sigmoidal concentration-time profiles are systematically analyzed to clarify their correct characterization and classification. This procedure has led us to refine the definitions of autocatalysis and autocatalyst. A kinetic phenomenon where a product of the overall chemical event serves as a catalyst for at least one of its subsystems or for the whole system itself is called autocatalysis. This definition makes it clear that in the case of autocatalysis, the concentration of autocatalyst necessarily increases during the course of any real overall chemical or biochemical reaction. CTx-648 Histone Acetyltransf inhibitor The way it is achieved thereby provides a suitable tool to classify autocatalytic processes by their elucidated and fine mechanistic details.Correction for ‘Tuning trion binding energy and oscillator strength in a laterally finite 2D system CdSe nanoplatelets as a model system for trion properties’ by Sabrine Ayari et al., Nanoscale, 2020, 12, 14448-14458, DOI .We report conversion of esters to thioesters via selective C-O bond cleavage/weak C-S bond formation under transition-metal-free conditions. The method is notable for a general and practical transition-metal-free system, broad substrate scope and excellent functional group tolerance. The strategy was successfully deployed in late-stage thioesterification, site-selective cross-coupling/thioesterification/decarbonylation and easy-to-handle gram scale thioesterification. Selectivity and computational studies were performed to gain insight into the formation of weak C-S bonds by C-O bond cleavage, which contrasts with the traditional trend of nucleophilic additions to carboxylic acid derivatives.Encouraged by the successful syntheses of alloy nanoclusters (or nanoparticles) via intercluster (or interparticle) reactions, herein we apply this methodology to prepare a series of bimetallic hydride clusters. Mixing of two clusters, [Ag7(H)E2P(OiPr)26] (E = S, 1; Se, 3) and [Cu7(H)E2P(OiPr)26] (E = S, 2; Se, 4), yields two series of hydride-centered bimetallic clusters, [CuxAg7-x(H)E2P(OiPr)26] (x = 0-7; E = S, 5; Se, 6). Their compositions are fully characterized by positive-mode ESI-MS spectrometry, multi-NMR spectroscopy, and the structures of [Cu6Ag(H)S2P(OiPr)26] (5a) and [CuAg6(H)Se2P(OiPr)26] (6a) by single crystal X-ray diffraction. The presence of individual compounds in solution is the result of a (dynamic) chemical equilibrium primarily driven by metal exchanges. In fact, the process of inter-cluster exchange of 1 and 2 leading to hydride-centered bimetallic clusters 5 can be monitored by concentration-dependent 31P NMR spectroscopy of which the higher concentration of 1 in the reaction, the closer to its resonance will be the distribution, in accord with Le Chatelier’s principle.