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Hydrogen is a potential energy carrier in comparison to conventional fuels due to its high energy content. Methane is an attractive source for 'on‐site' production of hydrogen by using membrane reformer due to its low cost. However, such reformers are not well studied and high temperature operation of steam methane reforming (SMR) makes the integration with membrane separation difficult. Further, the main product of SMR is CO and H2 in which CO has an inhibition effect on the membrane separation process. Therefore, it is vital to synthesize a low temperature and low CO selective catalyst for a suitable integration with membrane reformer. Nickel‐based catalyst is widely used for SMR due to its low cost and high catalytic activity. CeO2 is a favoured support as it mobilizes the lattice oxygen and reduces the coke formation and CO selectivity. Though several studies are reported on CeO2 based support, the effect of CeO2 surface morphology is not studied for SMR. In the current work, Ni/CeO2 of different shapes (nanocube and nanorod) are synthesized. The complete characterization of the support was performed. The effect of support shape, calcination temperature, and reduction temperature on SMR activity is found at different operating temperatures. For each condition conversion, CO, CO2 selectivity, and hydrogen yield are calculated. The results show the CeO2 morphology has a considerable effect on conversion, CO selectivity, and hydrogen yield. It is found that ceria nanocube calcined at 550°C provides better performance at high temperature. [ABSTRACT FROM AUTHOR]

Tyrosine phosphorylation has emerged as an important regulator of plasma membrane-localized immune receptors activity. Here, we investigate the role of tyrosine phosphorylation in the regulation of rice XANTHOMONAS RESISTANCE 21 (XA21)-mediated immunity. We demonstrate that the juxtamembrane and kinase domain of Escherichia coli-expressed XA21 (XA21JK) autophosphorylates on tyrosine residues. Directed mutagenesis of four out of the nine tyrosine residues in XA21JK reduced autophosphorylation. These sites include Tyr698 in the juxtamembrane domain, and Tyr786, Tyr907, and Tyr909 in the kinase domain. Rice plants expressing XA21-GFP fusion proteins or proteins with these tyrosine residues individually mutated to phenylalanine (XA21YF-GFP), which prevents phosphorylation at these sites, maintain resistance to Xanthomonas oryzae pv. oryzae. In contrast, plants expressing phosphomimetic XA21 variants with tyrosine mutated to aspartate (XA21YD-GFP) were susceptible. In vitro purified XA21JKY698F, XA21JKY907F, and XA21JKY909F variants are catalytically active, whereas activity was not detected in XA21JKY768F and the four XA21JKYD variants. We previously demonstrated that interaction of XA21 with the co-receptor OsSERK2 is critical for biological function. Four of the XA21JKYF variants maintain interaction with OsSERK2 as well as the XA21 binding (XB) proteins XB3 and XB15 in yeast, suggesting that these four tyrosine residues are not required for their interaction. Taken together, these results suggest that XA21 is capable of tyrosine autophosphorylation, but the identified tyrosine residues are not required for activation of XA21-mediated immunity or interaction with predicted XA21 signaling proteins.

This study examined the effect of various promoters (Co, Cr, Fe, Zr) in reducing NO using the NH3-SCR reaction on the MnO2/CeO2-Nanorod catalysts. The physicochemical properties of these catalysts were characterized using Brunauer–Emmett–Teller, X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscope, scanning electron microscope-energy dispersive X-ray spectroscopy, and Raman spectroscopy. Characterization analysis revealed uniform dispersion of active metals on CeO2-Nanorod supports, desired active metal-support synergism, small crystallite sizes, high specific surface areas, and an appreciable amount of surface lattice oxygen in Co–MnO2/CeO2-Nanorod catalysts. Co–MnO2/CeO2-Nanorod catalyst showed the best NH3-SCR activity at low temperatures. The NO conversion and N2 selectivity are 87 and 85%, respectively, at 300 °C with excellent stability. The Co–MnO2/CeO2-Nanorod catalyst also showed excellent tolerance against the H2O and the SO2. The catalyst's performance can be attributed to its high surface area, oxygen storage capacity, high Ce3+ content, and evenly distributed promoters. [ABSTRACT FROM AUTHOR]

CeO2–nanorod support was synthesized by hydrothermal method and different manganese oxides (MnO, MnO2, and Mn2O3) were impregnated over support by the wet‐impregnation forming MnO/CeO2‐NR, MnO2/CeO2‐NRm and Mn2O3/CeO2‐NR. The physico‐chemical properties of the as‐prepared catalysts were analyzed using x‐ray diffraction (XRD), Brunauer–Emmett–Teller (BET) surface area, x‐ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscope–energy‐dispersive x‐ray spectroscopy (SEM–EDX), hydrogen‐temperature‐programmed reduction (H2‐TPR), and Raman spectroscopy. These catalysts were further analyzed for NO reduction using NH3 as a reducing gas in the temperature range of 50 to 450°C. The results confirmed that MnO2/CeO2‐NR gave the maximum NO conversion (65%) and N2 selectivity (89%) among all catalysts. Further, MnO2/CeO2‐NR catalyst was studied for the effect of MnO2 loading and more than 90% NO conversion and N2 selectivity were obtained in the temperature range of 250 to 300°C. [ABSTRACT FROM AUTHOR]

Highly efficient and low‐cost Pt‐Co/CAB bimetallic cathode electrocatalysts were synthesized for hydrogen‐based proton exchange membrane fuel cell (PEMFC) using three different types of solvent, namely, dimethyl sulphoxide (DMSO), dimethylformamide (DMF), and ethylene glycol (EG). The physical characterization of synthesized cathode electrocatalysts Pt‐Co/CAB‐DMSO, Pt‐Co/CAB‐DMF and Pt‐Co/CAB‐EG was performed by scanning electron microscope–energy‐dispersive X‐ray (SEM–EDX), X‐ray diffraction (XRD), and transmission electron microscopy (TEM) techniques, whereas the electrochemical investigation of all three Pt‐Co/CAB electrocatalysts was performed by CV and EIS studies. The synthesized Pt‐Co/C‐EG electrocatalyst produced the highest power density of 19.61 mW/cm2 at a room temperature of 33°C. The power density increased to 26.11 mW/cm2, that is, 133%, when the cell operating temperature was raised from 33 to 70°C. The excellent performance of the Pt‐Co/CAB‐EG cathode electrode proves that it can be recommended as a commercial electrocatalyst for PEMFC cathode. In addition, the EG/EG was identified as the best solvent for the synthesis of Pt‐Co/CAB cathode electrocatalysts. [ABSTRACT FROM AUTHOR]

Precise spatiotemporal and cell type-specific gene expression is essential for proper tissue development and function. Transcription factors (TFs) guide this process by binding to developmental stage-specific targets and establishing an appropriate enhancer landscape. In turn, DNA and chromatin modifications direct the genomic binding of TFs. However, how TFs navigate various chromatin features and selectively bind a small portion of the millions of possible genomic target loci is still not well understood. Here we show that Cdx2 - a pioneer TF that binds distinct targets in developing versus adult intestinal epithelial cells - has a preferential affinity for a non-canonical CpG-containing motif in vivo . A higher frequency of this motif at embryonic and fetal Cdx2 target loci and the specifically methylated state of the CpG during development allows selective Cdx2 binding and activation of developmental enhancers and linked genes. Conversely, demethylation at these enhancers prohibits ectopic Cdx2 binding in adult cells, where Cdx2 binds its canonical motif without a CpG. This differential Cdx2 binding allows for corecruitment of Ctcf and Hnf4, facilitating the establishment of intestinal superenhancers during development and enhancers mediating adult homeostatic functions, respectively. Induced gain of DNA methylation in the adult mouse epithelium or cultured cells causes ectopic recruitment of Cdx2 to the developmental target loci and facilitates cobinding of the partner TFs. Together, our results demonstrate that the differential CpG motif requirements for Cdx2 binding to developmental versus adult target sites allow it to navigate different DNA methylation profiles and activate cell type-specific genes at appropriate times.