Tailored Platinum Group Metal/Spinel Oxide Catalysts for Dynamically Enhanced Methane Oxidation.

A combined experimental and molecular modeling study identifies a family of spinel oxides that in combination with PGM (platinum group metals) provide enhanced methane oxidation activity. With a reduction in greenhouse gas (GHG) emissions urgently needed, there is renewed interest in the use of natural gas vehicles (NGVs) and engines (NGEs) for transportation, commerce, and industrial applications. NGVs and NGEs emit less CO2 than their petroleum-derived counterparts but may emit uncombusted methane, an even more potent GHG. For stoichiometric engines, methane oxidation catalysts containing PGM and spinel oxide in layered architectures offer increased methane oxidation activity and lower light-off temperatures (T50). The reducible spinel oxide has direct and indirect roles that are effectively described by the bulk oxygen vacancy formation energy (Evac). We apply density functional theory (DFT) to identify several earth-abundant, cobalt-rich spinel oxides with favorable Evac, shown to correlate with dynamic oxygen storage capacity (DOSC) and CO and H2 oxidation activity. We experimentally rank-order the DFT-identified spinel oxides in combination with Pt+Pd for their methane oxidation activity measurements, under both time-invariant and modulated feed conditions. We show good agreement between the activity and the DFT-computed reducibility of the spinel oxide. The findings suggest spinel reducibility is a key factor in achieving enhanced low-temperature methane conversion, enabled through a balance of methane activation on the PGM sites and subsequent oxidation of the intermediates and byproducts on spinel oxides. In agreement with its computationally predicted Evac, NiCo2O4 was confirmed to have the highest DOSC and lowest T50 among the tested spinel samples.

Thermolysis of microalgae and duckweed in a CO2-swept fixed-bed reactor: bio-oil yield and compositional effects.

Microalgae and duckweed were grown and harvested over a three-month period in CO(2)-sparged helioreactors and open earthen ponds, respectively. The biomass feedstocks were thermolyzed in a thermogravimetric analyzer (TGA) and fixed-bed reactor to produce a fuel precursor coined "bioleum". Analysis of the thermolysis kinetics revealed an increase in the activation energy with heating rate for both aquatic species. Activation energies were lower than literature-reported values for lignocellulosics, corroborated by TGA thermolysis of pinewood. Thermolysis of microalgae resulted in higher bioleum and energy yields than for duckweed, reflecting differences in the biomass composition. The algal bioleum properties resemble those of crude petroleum except for higher nitrogen and oxygen content and acid number. Speciation identified 300+ compounds in the oil phase, with similar amounts of hydrocarbons and oxygenates, while acetic acid was the major species in the aqueous phase. The compounds were classified according to their degree of aromaticity, oxygenation, and nitrogenation.

Tocilizumab treatment of rheumatoid arthritis among Filipino patients

Introduction. Studies have shown that tocilizumab (TCZ) is effective in the treatment of rheumatoid arthritis. This study examined the efficacy and safety of TCZ in Filipino patients with moderate to severe rheumatoid arthritis (RA). Methods. This was an open-label, one-arm clinical trial approved by the Philippine Council Health Research Development-National Ethics Committee (PCHRD-NEC), among moderate-severe active RA Filipino patients in 4 RA clinics. The study consisted of a 28-day screening-baseline period; a 24-week treatment period, with once every-4-weeks TCZ 8mg/kg intravenous infusion (IV) and an efficacy-safety evaluation. Patients already receiving methotrexate (MTX) at study entry went on with MTX plus TCZ per medical discretion. Descriptive statistics computed for physician's and patient's global assessment of disease activity, patient's global assessment of pain, ACR20, ACR50 and ACR70. Analysis of variance (ANOVA) determined significant changes over time for DAS-28 ESR, FACIT and HAQ-DI fatigue scores. Twenty-nine of thirty patients were included in efficacy and safety analysis. Results. After 24 weeks of TCZ: 86%, 66%, and 48% of 29 Filipino RA patients achieved ACR20, ACR50, ACR70, respectively, with 34% achieving remission according to DAS28-ESR. Median times to first achieving ACR20, ACR50 and ACR70 were 4, 12, and 24 weeks, respectively. There were also significant rapid reductions in physician's and patient's global assessment of disease activity, patient's global assessment of pain, HAQ-DI and FACIT scores noted over time. Tolerability profile was similar to published literature on TCZ. Conclusions. TCZ has been shown to be effective in the treatment of Filipino patients with moderate to severe rheumatoid arthritis. TCZ can be given in an out-patient RA clinic setting.