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1. Comparative performance of Fe‐ MO_x / SiO₂ (M = V, Mn, Co, Ni, Cu, Mo) and FeO_x / SiO₂ catalysts in reductive liquefaction of switchgrass in ethanol

   https://doi.org/10.1002/bbb.2720  

   Amarasekara, Ananda S; Morales, Gabriel Murillo; Kommalapati, Raghava R (March 2025, Biofuels, Bioproducts and Biorefining)

   Abstract The catalytic hydrothermal liquefaction of biomass under a hydrogen atmosphere is a promising technology to produce stable biocrude oil as a sustainable alternative to petroleum crude. A series of iron‐based non‐noble mix metal‐oxide‐on‐silica catalysts were evaluated to mimic the natural transformation that may have led to the conversion of terrestrial biomass to fossilized fuels. Switchgrass powder was liquefied to a stable bio‐oil with a 71.2% yield by using FeO_x/SiO₂catalyst in ethanol under a 5.5 MPa hydrogen atmosphere at 210 °C. The use of Fe‐MO_x/SiO₂(M = V, Mn, Co, Ni, Cu and Mo) type bimetallic oxide catalysts instead of FeO_x/SiO₂can produce improvements in liquefaction yields by using Mn, Co, Ni, and Cu as the second metal. The highest liquefaction yield of 78.8% was observed with the Fe‐CuO_x/SiO₂catalyst. Liquefaction oils were formed that were composed of complex mixtures of C6‐C12 alcohols, esters, aldehydes, and phenols. The lignin products:holocellulose products ratio changed in the range 0.35 to 0.15 and the composition of oils changed significantly with the use of mixed metal oxides in place of single metal FeO_x/SiO₂The most effective catalyst, Fe‐CuO_x/SiO₂could be reused in five cycles with a small loss in liquefaction yield from 78.8% to 70.0% after four reuse cycles and after regeneration of the catalyst at 500 °C for 3 h in air. 

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2. Molecularly engineering polymeric membranes for H₂ / CO₂ separation at 100–300 °C

   https://doi.org/10.1002/pol.20200220  

   Hu, Leiqing; Pal, Sankhajit; Nguyen, Hien; Bui, Vinh; Lin, Haiqing (July 2020, Journal of Polymer Science)

   Abstract Over the last two decades, polymers with superior H₂/CO₂separation properties at 100–300 °C have gathered significant interest for H₂purification and CO₂capture. This timely review presents various strategies adopted to molecularly engineer polymers for this application. We first elucidate the Robeson's upper bound at elevated temperatures for H₂/CO₂separation and the advantages of high‐temperature operation (such as improved solubility selectivity and absence of CO₂plasticization), compared with conventional membrane gas separations at ~35 °C. Second, we describe commercially relevant membranes for the separation and highlight materials with free volumes tuned to discriminate H₂and CO₂, including functional polymers (such as polybenzimidazole) and engineered polymers by cross‐linking, blending, thermal treatment, thermal rearrangement, and carbonization. Third, we succinctly discuss mixed matrix materials containing size‐sieving or H₂‐sorptive nanofillers with attractive H₂/CO₂separation properties. 

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3. Quaternary cerium( iv ) containing fluorides exhibiting Ce ₃ F ₁₆ sheets and Ce ₆ F ₃₀ frameworks

   https://doi.org/10.1039/d0dt00616e  

   Ayer, Gyanendra B.; Klepov, Vladislav V.; Pace, Kristen A.; zur Loye, Hans-Conrad (May 2020, Dalton Transactions)

   null (Ed.)

   A series of new Ce( iv ) based fluorides with two different compositions, Cs 2 MCe 3 F 16 (M = Ni 2+ , Co 2+ , Mn 2+ , and Zn 2+ ) and Na 3 MCe 6 F 30 (M = Al 3+ , Ga 3+ , Fe 3+ , and Cr 3+ ) were synthesized as high quality single crystals via a mild hydrothermal route. The compounds with the composition Cs 2 MCe 3 F 16 (M = Ni 2+ , Co 2+ , Mn 2+ , and Zn 2+ ) crystallize in the hexagonal crystal system with space group P 6 3 / mmc and are isotypic with the uranium analogs, whereas the Na 3 MCe 6 F 30 (M = Al 3+ , Ga 3+ , Fe 3+ , and Cr 3+ ) compounds crystallize in the trigonal space group P 3̄ c 1 and are isotypic with the uranium and thorium analogs Na x MM′ 6 F 30 (M′ = Th, U). The Cs 2 MCe 3 F 16 compounds exhibit a complex 3D crystal structure constructed of edge-sharing cerium trimers, in which all three Ce atoms share a common μ 3 -F unit. The Na 3 MCe 6 F 30 compounds are constructed of edge- and vertex-sharing cerium polyhedra connected to each other to form Ce 6 F 30 6− framework, which can accommodate only relatively smaller trivalent cations (M 3+ = Al 3+ , Ga 3+ , Fe 3+ , and Cr 3+ ) as compared to uranium and thorium analogs. Magnetic susceptibility measurements were carried out on the samples of Cs 2 MCe 3 F 16 (M = Ni 2+ and Co 2+ ), which exhibit paramagnetic behavior. 

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4. MPK12 in stomatal CO₂ signaling: function beyond its kinase activity

   https://doi.org/10.1111/nph.18913  

   Yeh, Chung‐Yueh; Wang, Yuh‐Shuh; Takahashi, Yohei; Kuusk, Katarina; Paul, Karnelia; Arjus, Triinu; Yadlos, Oleksii; Schroeder, Julian I.; Ilves, Ivar; Garcia‐Sosa, Alfonso T.; et al (April 2023, New Phytologist)

   Summary Protein phosphorylation is a major molecular switch involved in the regulation of stomatal opening and closure. Previous research defined interaction between MAP kinase 12 and Raf‐like kinase HT1 as a required step for stomatal movements caused by changes in CO₂concentration. However, whether MPK12 kinase activity is required for regulation of CO₂‐induced stomatal responses warrants in‐depth investigation.We apply genetic, biochemical, and structural modeling approaches to examining the noncatalytic role of MPK12 in guard cell CO₂signaling that relies on allosteric inhibition of HT1.We show that CO₂/HCO₃⁻‐enhanced MPK12 interaction with HT1 is independent of its kinase activity. By analyzing gas exchange of plant lines expressing various kinase‐dead and constitutively active versions of MPK12 in a plant line whereMPK12is deleted, we confirmed that CO₂‐dependent stomatal responses rely on MPK12's ability to bind to HT1, but not its kinase activity. We also demonstrate that purified MPK12 and HT1 proteins form a heterodimer in the presence of CO₂/HCO₃⁻and present structural modeling that explains the MPK12:HT1 interaction interface.These data add to the model that MPK12 kinase‐activity‐independent interaction with HT1 functions as a molecular switch by which guard cells sense changes in atmospheric CO₂concentration. 

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5. ND70 Series Basaltic Glass Reference Materials for Volatile Element ( H₂O , CO₂ , S, Cl, F) Measurement and the C Ionisation Efficiency Suppression Effect of Water in Silicate Glasses in SIMS

   https://doi.org/10.1111/ggr.12572  

   Moussallam, Yves; Towbin, William Henry; Plank, Terry; Bureau, Hélène; Khodja, Hicham; Guan, Yunbin; Ma, Chi; Baker, Michael B; Stolper, Edward M; Naab, Fabian U; et al (July 2024, Geostandards and Geoanalytical Research)

   We present a new set of reference materials, the ND70‐series, forin situmeasurement of volatile elements (H₂O, CO₂, S, Cl, F) in silicate glass of basaltic composition. The materials were synthesised in piston cylinders at pressures of 1 to 1.5 GPa under volatile‐undersaturated conditions. They span mass fractions from 0 to 6%m/mH₂O, from 0 to 1.6%m/mCO₂and from 0 to 1%m/mS, Cl and F. The materials were characterised by elastic recoil detection analysis for H₂O, by nuclear reaction analysis for CO₂, by elemental analyser for CO₂, by Fourier transform infrared spectroscopy for H₂O and CO₂, by secondary ion mass spectrometry for H₂O, CO₂, S, Cl and F, and by electron probe microanalysis for CO₂, S, Cl and major elements. Comparison between expected and measured volatile amounts across techniques and institutions is excellent. It was found however that SIMS measurements of CO₂mass fractions using either Cs⁺or O⁻primary beams are strongly affected by the glass H₂O content. Reference materials have been made available to users at ion probe facilities in the US, Europe and Japan. Remaining reference materials are preserved at the Smithsonian National Museum of Natural History where they are freely available on loan to any researcher. 

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