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Abstract This work presents a novel study for identifying alterations in the control states of a desuperheater system based on real closed-loop data from a coal-fired power plant operating under various loads using linear and nonlinear system identification techniques. Specifically, Transfer Functions (TFs) and Gaussian Processes within a Nonlinear AutoRegressive eXogenous model (GP-NARX) are utilized. The desuperheater system comprises two units, north and south, each modeled as a single-input single-output (SISO) system based on spray valve positions and outlet temperatures. To identify changes in the control states using TFs, deviations in the coefficients of three poles and two zeros transfer functions are analyzed. Significant shifts in the control states of the north desuperheater are observed when transitioning from nominal to half and low loads, with deviations of up to four orders of magnitude. Substantial changes in control states are also observed for the south desuperheater when moving from nominal to low load, with a deviation in the coefficients of up to five orders of magnitude, whereas the transition from nominal to half load shows a smaller deviation of up to three orders of magnitude. In the GP-NARX approach, model uncertainties are used to indicate the changes in the control states. The south desuperheater showed a significant uncertainty of up to 8°F from the nominal to the low load, evidencing a change in the control states. Regarding the north desuperheater, increased uncertainty, up to 6°F, is also observed but in shorter time intervals when compared to the south desuperheater. Ultimately, this work shows that both approaches can be used as a basis for system identification, employing real closed-loop power plant data. 

Abstract The electrochemical carbon dioxide reduction reaction (CO₂RR) is a promising approach for reducing atmospheric carbon dioxide (CO₂) emissions, allowing harmful CO₂to be converted into more valuable carbon‐based products. On one hand, single carbon (C₁) products have been obtained with high efficiency and show great promise for industrial CO₂capture. However, multi‐carbon (C₂₊) products possess high market value and have demonstrated significant promise as potential products for CO₂RR. Due to CO₂RR's multiple pathways with similar equilibrium potentials, the extended reaction mechanisms necessary to form C₂₊products continue to reduce the overall selectivity of CO₂‐to‐C₂₊electroconversion. Meanwhile, CO₂RR as a whole faces many challenges relating to system optimization, owing to an intolerance for low surface pH, systemic stability and utilization issues, and a competing side reaction in the form of the H₂evolution reaction (HER). Ethylene (C₂H₄) remains incredibly valuable within the chemical industry; however, the current established method for producing ethylene (steam cracking) contributes to the emission of CO₂into the atmosphere. Thus, strategies to significantly increase the efficiency of this technology are essential. This review will discuss the vital factors influencing CO₂RR in forming C₂H₄products and summarize the recent advancements in ethylene electrosynthesis. 

Abstract Catalytic membranes offer opportunities to develop modular, process‐intensified units. Dual‐functional materials, which integrate reactive and separation components in a single material, could play an important role in enabling them. Adapting the various characterization tools that are used to analyze the structures of metal‐based catalysts to these integrated structures could provide vital information for their design and implementation. In this perspective, we highlight the ways in which these tools can be used to analyze nonreactive membranes and non‐integrated systems where the catalyst and the membrane operate as two separate units. A methodology developed to analyze these comparatively simpler systems could be subsequently extended to integrated dual‐functional catalytic membranes. Thus, researchers from the catalysis and membranes communities can work together in a way that will not only lead to fundamental advancements in our understanding of catalytic membranes but also enable their transformation into real, scalable process‐intensified units. 

Abstract In this work, an organic‐inorganic hybrid crystal, violet‐crystal (VC), was used to etch the nickel foam (NF) to fabricate a self‐standing electrode for the water oxidation reaction. The efficacy of VC‐assisted etching manifests the promising electrochemical performance towards the oxygen evolution reaction (OER), requiring only ~356 and ~376 mV overpotentials to reach 50 and 100 mA cm⁻², respectively. The OER activity improvement is attributed to the collectively exhaustive effects arising from the incorporation of various elements in the NF, and the enhancement of active site density. Furthermore, the self‐standing electrode is robust, exhibiting a stable OER activity after 4,000 cyclic voltammetry cycles, and ~50 h. The anodic transfer coefficients (α_a) show that the first electron transfer step is the rate‐determining step on the surface of NF‐VCs‐1.0 (NF etched by 1 g of VCs) electrode, while the chemical step involving dissociation following the first electron transfer step is identified as the rate‐limiting step in other electrodes. The lowest Tafel slope value observed in the NF‐VCs‐1.0 electrode indicates the high surface coverage of oxygen intermediates and more favorable OER reaction kinetics, as confirmed by high interfacial chemical capacitance and low charge transport/interfacial resistance. This work demonstrates the importance of VCs‐assisted etching of NF to activate the OER, and the ability to predict reaction kinetics and rate‐limiting step based onα_avalues, which will open new avenues to identify advanced electrocatalysts for the water oxidation reaction. 

Abstract Porous electrodes that conduct electrons, protons, and oxygen ions with dramatically expanded catalytic active sites can replace conventional electrodes with sluggish kinetics in protonic ceramic electrochemical cells. In this work, a strategy is utilized to promote triple conduction by facilitating proton conduction in praseodymium cobaltite perovskite through engineering non‐equivalent B‐site Ni/Co occupancy. Surface infrared spectroscopy is used to study the dehydration behavior, which proves the existence of protons in the perovskite lattice. The proton mobility and proton stability are investigated by hydrogen/deuterium (H/D) isotope exchange and temperature‐programmed desorption. It is observed that the increased nickel replacement on the B‐site has a positive impact on proton defect stability, catalytic activity, and electrochemical performance. This doping strategy is demonstrated to be a promising pathway to increase catalytic activity toward the oxygen reduction and water splitting reactions. The chosen PrNi_0.7Co_0.3O_3−δoxygen electrode demonstrates excellent full‐cell performance with high electrolysis current density of −1.48 A cm⁻²at 1.3 V and a peak fuel‐cell power density of 0.95 W cm⁻²at 600 °C and also enables lower‐temperature operations down to 350 °C, and superior long‐term durability. 

CO and/or H₂O on mesoporous oxide supported metal catalysts are reviewed from our research and literature in 2020–2025, for WGS, CO oxidation, and F–T synthesis, with focuses on advanced spectroscopic techniques and metal–support interactions.