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The change of the desulfurization product rate with the radial distance is the same under different superficial gas velocities, with the peak desulfurization efficiency appearing in the annulus. The optimal operating parameter for the desulfurization process is available in PPSB, and the desulfurization efficiency and gas handling capacity reach the best result when the superficial gas velocity equals 1.2 Ums. Copyright © 2020 American Chemical Society.Type IV secretion systems are large nanomachines assembled across the bacterial cell envelope for effector translocation and conjugation. VirB10 traverses the inner and outer membranes, sensing cellular signals for coordinating the conformational switch for pilus biogenesis and/or secretion. Mutations uncoupling secretion from pilus biogenesis were identified in Agrobacterium tumefaciens VirB10 including a gating defect mutation G272R that made VirB10 unresponsive to intracellular ATP, causing unregulated secretion of VirE2 in a contact-independent manner. Comparative long-timescale molecular dynamics of the wild type and G272R mutant of the A. tumefaciens VirB10CTD tetradecamer reveals how the G272R mutation locks the oligomer in a rigid conformation by swapping the ionic interactions between the loops from the β-barrel close to the inner leaflet of the outer membrane. This electrostatic switching changes the allosteric communication pathway from the extracellular loop to the base of the barrel, suggesting that the local conformational dynamics in the loops can gate information across VirB10. Copyright © 2020 American Chemical Society.Antimicrobial peptides (AMPs), an essential component of innate immunity, are very important resources for human therapeutics to counter the current threat of drug resistance. [https://www.selleckchem.com/products/u73122.html selleckchem] We have previously established that one such AMP, α-melanocyte stimulating hormone (α-MSH), an endogenous neuropeptide, and its derivatives have potent antimicrobial activity against Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA). However, the immense potential of α-MSH for therapeutic development against staphylococcal infections is marred by its reduced efficacy in the presence of standard microbiological culture medium. To overcome this issue, in this study, we designed a series of five novel analogues of the C-terminal fragment of α-MSH, i.e., α-MSH(6-13), by replacing uncharged and less hydrophobic residues with tryptophan and arginine to increase the hydrophobicity and cationic charge of the peptide, respectively. While all of the peptides showed a preferential interaction with negatively charged phospholipid vesicles, the most hydrophobic and cationic peptide, i.e., Ana-5, exhibited the highest activity against S. aureus cells while maintaining cell selectivity. Moreover, Ana-5 could retain its activity even in complex media like the Mueller Hinton broth and displayed rapid bactericidal activity in the presence of serum. Ana-5 also caused rapid bacterial membrane depolarization, permeabilization, and cell lysis and was able to bind to polyanionic plasmid DNA suggesting a possible dual mode of action of the peptide. Importantly, Ana-5 was able to eradicate intracellular S. aureus in fibroblast cells similar to conventional antibiotics. Collectively, in the present study, we obtained a potent α-MSH-based analogue with excellent staphylocidal potency in microbial growth medium and ex vivo efficacy, which may translate into therapeutic application. Copyright © 2020 American Chemical Society.Butanol is attracting more attention as an alternative fuel. The performance and emissions of butanol/ethanol-gasoline (E10) was investigated in a spark ignition engine. Exhaust gas recirculation (EGR) was employed to improve the engine performance and emissions in this reported test. The experimental results showed that high brake thermal efficiency (BTE) was observed with a high proportion of blended fuels in comparison to E10. During EGR operation, the introduction of butanol changed the combustion behavior, including prolonged ignition delay, shortened rapid burning duration, a reduced knock number, and knock intensity. The brake-specific fuel consumption (BSFC) increased with butanol addition, and when EGR was introduced, it decreased similarly to E10. The butanol-E10 blends exhibited lower exhaust gas temperature in comparison to E10 at various EGR rates. Hydrocarbon emissions from the blends increased slightly with the increased EGR rate, whereas CO emissions decreased. EGR exhibited high inhibition of NO x emissions for both blended fuels and E10, which were reduced by more than 80%. The NO x emissions from the blended fuels were 20-30% less than that of E10 with or without EGR conditions. Finally, EGR contributed to a reduction in BSFC and improvement in BTE for the butanol-E10 engine. The butanol-E10 blends exhibited a similar power performance, slightly reduced combustion stability, and acceptable emissions with respect to the baseline conditions. Copyright © 2020 American Chemical Society.We report on the structural and optical properties of Fe2CrO4+δ epitaxial films grown by molecular beam epitaxy on MgAl2O4 (001) as a function of δ (average cation valence). The average Fe valence is linked to the out-of-plane lattice parameter and the extent of light absorption in the infrared spectral region. Over-oxidized films (0 less then δ less then 0.5) exhibit smaller lattice parameters and suppressed infrared absorption. The lattice parameter is found to differ for films of equivalent oxidation state but different thermal histories. We discuss the behavior of a novel infrared transition present at ∼0.6 eV in Fe2CrO4 films deposited at or above 400 °C. An optical transition found in all films at 0.9 eV independent of the synthesis temperature can be used to quantify the oxidation state of Fe2CrO4+δ. This research provides new insights into the atomic structure, optical processes, oxidation states, electronic structure, and application potential of Fe2CrO4+δ. Copyright © 2020 American Chemical Society.Two trimellitic anhydride-functionalized, thermally reduced graphenes with different aspect ratios, A f, and the same C/O ratio (81) were prepared and melt-mixed into poly(ethylene terephthalate) (PET), and the mechanical properties of the resulting nanocomposites were studied with a focus on plastic deformation behavior. A slight increase in the G' of the melt was observed for the surface-modified low-A f graphene composites (A f = 20) below the percolation threshold, whereas a significant enhancement in G' was observed for higher-A f graphene composites (A f = 80) at all graphene loadings, both below and above the percolation concentration. Furthermore, the use of modified low-A f graphene caused an improvement both in Young's modulus and elongation at break of the resulting PET nanocomposites because of enhancement of interfacial adhesion between filler and matrix which resulted in the formation of a coupled network via covalent bonding and the suppression both of strain-induced orientation and strain-induced crystallization.