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Solid oxide fuel cells are characterized by a high efficiency for converting chemical energy into electricity and fuel flexibility. This research work focuses on developing durable and efficient anodes for solid oxide fuel cells (SOFCs) based on exsolving nickel from the perovskite structure. A-site-deficient La- and Ni-doped strontium titanates (La0.2Sr0.7Ti0.95Ni0.05O3−δ, LSTN) were synthesized using four different techniques and mixed with Ce0.8Gd0.2O2−δ (GDC) to form the SOFC anode. The synthesis routes of interest for comparison included solid-state, sol-gel, hydrothermal, and co-precipitation methods. LSTN powders were characterized via XRD, SEM, TPR, BET and XPS. In situ XRD during reduction was measured and the reduced powders were analyzed using TEM. The impact of synthesis route on SOFC performance was investigated. All samples were highly durable when kept at 0.5 V for 48 h at 800 °C with H2 fuel. Interestingly, the best performance was observed for the cell with the LSTN anode prepared via co-precipitation, while the conventional solid-state synthesis method only achieved the second-best results. [ABSTRACT FROM AUTHOR]

Unused animal waste rendered fat is a potential feedstock for marine biofuels. In this work, bio-oil was generated using hydrothermal liquefaction (HTL) of nitrogen-free and low sulfur rendered bovine fat. Maximum bio-oil yield of 28 ± 1.5% and high heating value of 38.5 ± 0.16 MJ·kg-1 was obtained at 330 ℃ at 50% animal fat solid load and 20 min retention time. The nitrogen and sulfur content were negligible, making the produced bio-oil useful marine biofuel, taking into account current stringent regulations on NOx and SOx emissions. The economic analysis of the process, where part of the bovine fat waste is converted to the bio-oil and the semi-solid residues can be used to supply the heat demand of the HTL process and alternately generate electricity, showed that our process is likely to generate a positive profit margin on a large scale. We also showed the growing economic importance of electricity in the revenues as commercial production becomes more energy efficient. [ABSTRACT FROM AUTHOR]

Axonal degeneration is an important determinant of progressive neurological disability in multiple sclerosis (MS). Thus, therapeutic approaches promoting neuroprotection could aid the treatment of progressive MS. Here, we used what we believe is a novel water-soluble fullerene derivative (ABS-75) attached to an NMDA receptor antagonist, which combines antioxidant and anti-excitotoxic properties, to block axonal damage and reduce disease progression in a chronic progressive EAE model. Fullerene ABS-75 treatment initiated after disease onset reduced the clinical progression of chronic EAE in NOD mice immunized with myelin-oligodendrocyte glycoprotein (MOG). Reduced disease progression in ABS-75-treated mice was associated with reduced axonal loss and demyelination in the spinal cord. Fullerene ABS-75 halted oxidative injury, [CD11b.sup.+] infiltration, and CCL2 expression in the spinal cord of mice without interfering with antigen-specific T cell responses. In vitro, fullerene ABS-75 protected neurons from oxidative and glutamate-induced injury and restored glutamine synthetase and glutamate transporter expression in astrocytes under inflammatory insult. Glutamine synthetase expression was also increased in the white matter of fullerene ABS-75-treated animals. Our data demonstrate the neuroprotective effect of treatment with a fullerene compound combined with a NMDA receptor antagonist, which may be useful in the treatment of progressive MS and other neurodegenerative diseases., Introduction Epidemiologic studies show that approximately 85% of patients with MS initially develop a relapsing-remitting form of the disease (1), (2). However, within 10 years, approximately half of those with [...]

A novel methodology is developed for the evaluation of receptor arrangement in structurally flexible anion chemosensors and is applied to map the binding site of a new pseudocyclic tristhiourea chemosensor. The binding patterns are found to be different for the chemosensors, indicating dissimilarity in the arrangement of the binding sites of pseudocyclic tristhiourea chemosensor and macrocyclic chemosensor.

A series of new adamantyl-oligoethyleneglycol-fullerene hybrids are prepared through Bingel-Hirsch functionalization of the C(sub 60) fullerene with various adamantyl-oligoethyleneglycol malonates. As N-methyl-D-aspartate (NMDA)-targeted antioxidants, these compounds might have the potential to be developed as therapeutic agents for the treatment of neurological disorders.

Due to the global COVID-19 pandemic, there is a need to screen for novel compounds with antiviral activity against SARS-COV-2. Here we compared chemical composition and the in vitro anti- SARS-COV-2 activity of two different Ulva sp. crude ulvan extracts: one obtained by an HCl-based and another one by ammonium oxalate-based (AOx) extraction protocols. The composition of the crude extracts was analyzed and their antiviral activity was assessed in a cytopathic effect reduction assay using Vero E6 cells. We show that the extraction protocols have a significant impact on the chemical composition, anti- SARS-COV-2 activity, and cytotoxicity of these ulvan extracts. The ulvan extract based on the AOx protocol had a higher average molecular weight, higher charge, and 11.3-fold higher antiviral activity than HCl-based extract. Our results strongly suggest that further bioassay-guided investigation into bioactivity of compounds found in Ulva sp. ulvan extracts could lead to the discovery of novel antiSARS-CoV-2 antivirals. [ABSTRACT FROM AUTHOR]

A rhodium complex initiates a reaction involving removal of a methylene (CH2) group from a methyl (CH3) group and subsequent insertion into different bonds, such as Si-H, Si-Si and C-H. This transfer of methylene group indicates the probability of functionalization of an unstrained carbon-carbon single bond through hydrosilylation. Thermodynamics influence these reactions in a positive manner.

A new approach to activate a carbon-carbon bond in solution has been followed by using the process of activating a simple C-C bond by a mononuclear rhodium complex in a neutral homogeneous medium, because C-C bonds usually do not react when transition metals in solutions are inserted. A metal-hydride complex was used to find if the transition-mental insertion into a C-C bond is possible. Slight heating helped to remove the kinetic barrier which obstructed C-C division. This new approach states that although metal pre-coordination aids C-C activation, it need not be absolutely essential if selective transformation of C-C bonds can be achieved by homogenous activation.

Synthesis of the soluble and asymmetrical ferrocene-terminated phenylethynyl oligomers was examined. The results suggested that the successful synthesis of these oligomers requires the protection of arenethiols, the introduction of appropriate substituents onto the phynel groups and the construction of of the oligomers with the right sequences. Furhermore, two types of protection groups for arenethiols were shown labile eiher o bases upon activation or to the fluorides. These protection groups were also shown useful in the protection of the unsaturated thiols such as alkenylthiols.

Due to a significant and prolific activity in the field of design and synthesis of new energetic molecules, it becomes increasingly difficult to introduce new explosophore structures with attractive properties. In this work, we synthesized a trans-bimane-based energetic material—3,7-diamino-2,6-dinitro-1H,5H-pyrazolo-[1,2-a]pyrazole-1,5-dione (4), the structure of which was comprehensively analyzed by a variety of advanced spectroscopic methods and by X-ray crystallo-graphy (with density of 1.845 g·cm−3 at 173 K). Although obtained crystals of 4 contained solvent molecules in their structure, state-of-the-art density functional theory (DFT) computational techniques allowed us to predict that solvent-free crystals of this explosive would preserve a similar tightly packed planar layered molecular arrangement, with the same number of molecules of 4 per unit cell, but with a smaller unit cell volume and therefore higher energy density. Explosive 4 was found to be heat resistant, with an onset decomposition temperature of 328.8 °C, and was calculated to exhibit velocity of detonation in a range of 6.88–7.14 km·s−1 and detonation pressure in the range of 19.14–22.04 GPa, using for comparison both HASEM and the EXPLO 5 software. Our results indicate that the trans-bimane explosophore could be a viable platform for the development of new thermostable energetic materials. [ABSTRACT FROM AUTHOR]