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Simple Summary: Muskrats' scented glands atrophy with the arrival of non-breeding periods, but the underlying mechanism is still unclear. Programmed cell death (PCD) is an important pathway of cell death that is closely related to the stability of the intracellular environment and the occurrence of diseases. Our research indicates that the expression levels of various apoptosis-and pyroptosis-related genes increase during the atrophy of muskrats' scented glands. Therefore, we believe that apoptosis and pyroptosis may be involved in the rapid atrophy of muskrats' scented glands during the non-breeding period. The muskrat (Ondatra zibethicus) is an animal with special economic significance whose scented glands rapidly atrophy during the non-breeding season, but the mechanism of atrophy is not clear, with significant differences in apoptotic and pyroptotic signaling pathway expression according to transcriptome sequencing. During the non-breeding season, key apoptosis-related genes such as Tnfr1 (TNF Receptor Superfamily Member 1A), TRADD (TNFRSF1A Associated via Death Domain), FADD (Fas Associated via Death Domain), Casp-8 (Cysteine-aspartic proteases-8), and Bax (Bcl-associated X protein) were upregulated in the scented glands, while Bcl2 (B-cell lymphoma-2) expression was downregulated. In the classical pyroptosis pathway, the mRNA expression levels of key genes including Nlrp3 (the Nod-like receptor family pyrin domain-containing 3), ASC (the apoptosis-associated speck-like protein), Casp-1 (Cysteine-aspartic proteases-1), Gsdmd (Gasdermin D), and IL-1β (Interleukin 1 Beta) were higher during the non-breeding season, similar to the transcription level of Ripk1 (Receptor Interacting Serine/Threonine Kinase 1) in the non-canonical pyroptosis pathway, while TAK1 (transforming growth factor kinase) expression was downregulated in this latter pathway. TUNEL assays and immunofluorescence analysis indicated increased apoptosis and GSDMD and Caspase-8 protein levels during the non-breeding season. Indeed, the protein levels of GSDMD-N, Caspase-8 p43, and Caspase-8 p18 were significantly higher during the non-breeding season, while the GSDMD levels were significantly lower compared to the secretion season. These results suggest that apoptosis and pyroptosis play regulatory roles in scented gland atrophy and that there is an interplay between them during this process. [ABSTRACT FROM AUTHOR]

Perovskite oxides show great promise as an alternative catalyst to the conventional nickel cermets for CO2 reduction reactions (CO2RR) in solid oxide electrolysis cells (SOECs) owing to their advantages of redox stability and coking resistance. Nevertheless, practical applications of these oxides are prevented largely by their poor CO2RR activities. Herein, a novel donor and acceptor co‐doped nonstoichiometric double perovskite, La0.3Sr1.55Fe1.5Ni0.1Mo0.4O6−δ (LSFNM), is developed with in situ exsolved FeNi3 nanoparticles to efficiently catalyze CO2RR in SOECs. Pure CO2 electrolysis over the impregnated FeNi3@LSFNM catalysts is evaluated on two types of SOECs—one with thin (ZrO2)0.89(Sc2O3)0.1(CeO2)0.01 (SSZ) electrolytes supported on 430L alloys and the other with thin La0.9Sr0.1Ga0.8Mg0.2O3−δ (LSGM) electrolytes supported on impregnated SmBa0.5Sr0.5Co2O5+δ (SBSCO)@LSGM anodes, producing unprecedently high current densities of 2.84 A cm−2 for the former and 3.07 A cm−2 for the latter at 1.5 V and 800 °C. Experimental analysis and density‐functional theory (DFT) calculations reveal collective synergistic catalysis of oxygen vacancies (VO..${V}_{\mathrm{O}}^{..}$), the doping Ni2+ ions and FeNi3 nanoparticles via the cooperative VO..${V}_{\mathrm{O}}^{..}$‐O(CO2), and Ni(II)–C(sp) and Ni(0)–O(CO2) interactions in LSFNM, not only facilitating CO2 chemisorption on oxygen vacancies but also destabilizing and dissociating surface carbonates in the vicinity of FeNi3 spontaneously into CO. [ABSTRACT FROM AUTHOR]

The insertion of carbonyl into C(sp2)−Pd(II) σ‐bond (Grignard‐type addition) was not established until the 1990s. While this elemental reaction has been well explored since then, its application in Pd(0) asymmetric catalysis remain elusive. Herein, we report the Pd(0)‐catalyzed asymmetric intramolecular Grignard‐type reaction of vinyl iodide‐carbonyl in the presence of HCO2H additive, affording cyclic allylic alcohol with good to excellent enantioselectivity and diastereoselectivity. Mechanistic studies suggested that besides serving as an efficient reductant, HCO2H is also capable of facilitating protonation of the involved secondary alkoxyl‐Pd(II), thus completely suppressing the β‐H elimination. Moreover, no KIE was found in the competing reaction between vinyl iodide‐aldehyde and 1‐deuterated one, demonstrating the facile step of aldehyde insertion. [ABSTRACT FROM AUTHOR]

Numerical modeling plays an important role in understanding the multi-physics coupling in solid oxide fuel/electrolysis cells (SOFCs/SOECs) operated at elevated temperatures. During long-term operation of SOFCs and SOECs, cell durability is limited by nickel (Ni) morphological changes and migration. To reveal the mechanisms behind these phenomena, a unified numerical model utilizing the phase-field (PF) method is integrated with a finite element (FE) multi-physics coupled heterogeneous single-cell model to quantitatively investigate the microstructure evolution of hydrogen electrodes operated in different modes. Based on the 3D microstructures of single-cell components reconstructed using the focused ion beam-scanning electron microscopy (FIB-SEM) technique, the performances of different cells and the corresponding microstructure evolutions caused by Ni coarsening and migration can be simulated under an identical framework in the FC and EC modes, taking into account the complex multi-physics coupling effects. It is shown that, in addition to conventional interfacial energies, the Ni migration driven by the electrochemical potential gradient induced by current also plays an important role in the microstructure evolution. The integrated model is also applied to the simulation of the microstructure evolution of the Ni–YSZ hydrogen electrode infiltrated with GDC nanoparticles to interpret their positive effect on the improvement of the electrode durability. [ABSTRACT FROM AUTHOR]

A phosphine‐catalyzed (3+2) annulation of 4‐acetoxy allenoate and aldimine with the assistance of AgF is described. The success of this reaction hinges on the metathesis between the enolate‐phosphonium zwitterion and AgF, leading to a key intermediate comprising of silver enolate and a fluorophosphorane P(V)‐moiety. The former is able to undergo a Mannich reaction with aldimine, whereas the latter initiates a cascade sequence of AcO‐elimination/aza‐addition, thus furnishing the P(III)/P(V) catalysis. By taking advantage of the silver enolate, a preliminary attempt at an asymmetric variant was conducted with the combination of an achiral phosphine catalyst and a chiral bis(oxazolinyl)pyridine ligand (PyBox), giving moderate enantioselectivity. [ABSTRACT FROM AUTHOR]

Solid oxide electrolysis cells (SOECs) are one of the most promising energy conversion devices due to their high efficiency and gas flexibility. However, the degradation of their performance during long-term operation limits their commercialization. Among the different phenomena, the degradation of Ni/yttria-stabilized zirconia (YSZ) fuel electrodes during long-term operation is recognized as one of the main causes for the loss in cell performance. Accordingly, numerous studies have focused on investigating the degradation of Ni/YSZ electrodes during steam electrolysis, whereas only limited studies have been performed on the stability of Ni/YSZ electrodes after long-term CO2 electrolysis. In this work, the microstructure evolution of Ni/YSZ electrodes after long-term operation in a CO/CO2 atmosphere was investigated. For this purpose, Ni/YSZ-supported planar-type SOEC cells were operated at 800 °C and −1 A cm−2 or zero current with a mixture of CO2/CO (90/10) supplied to the Ni/YSZ electrode. Subsequently, the 3D electrode microstructures of pristine cermet (reference) and after 1000 h operation were observed. A significant loss of Ni in the active electrode was observed in the cell operated at −1 A cm−2 for 1000 h, along with an increased Ni fraction in the support layer. An increase in the Ni particle size (i.e., Ni coarsening) was also observed. In the cell operated with zero current for 1000 h, only Ni coarsening was observed, with no Ni migration. Our results show that Ni migration away from the electrode/electrolyte interface also occurs during long-term CO2 electrolysis to a similar extent as in steam electrolysis. [ABSTRACT FROM AUTHOR]

Reductive elimination of alkyl−PdII−O is a synthetically useful yet underdeveloped elementary reaction. Here we report that the combination of an H‐bonding donor [PyH][BF4] and AgNO3 additive under toluene/H2O biphasic system can enable such elementary step to form alkyl nitrate. This results in the Pd0‐catalyzed asymmetric carbonitratations of (Z)‐1‐iodo‐1,6‐dienes with (R)‐BINAP as the chiral ligand, affording alkyl nitrates up to 96 % ee. Mechanistic studies disclose that the reaction consists of oxidative addition of Pd0 catalyst to vinyl iodide, anion ligand exchange between I− and NO3−, alkene insertion and SN2‐type alkyl−PdII−ONO2 reductive elimination. Evidences suggest that H‐bonding interaction of PyH⋅⋅⋅ONO2 can facilitate dissociation of O2NO− ligand from the alkyl−PdII−ONO2 species, thus enabling the challenging alkyl−PdII−ONO2 reductive elimination to be feasible. [ABSTRACT FROM AUTHOR]

The physicochemical properties of starch acetates with an equal degree of substitution prepared from pea, corn, and wheat starch and their effects on frozen cooked noodle (FCN) quality were investigated. The result showed that the three kinds of starch acetates had different effects on the quality of FCN due to their different blue values, freeze‐thaw stability, and crystalline morphology analyzed by XRD (p <.05). The FCN with the addition of 20% CAS exhibited slow deterioration of textural properties during holding for 30 min. The analysis of the changes in the content of free SH group and glutenin macropolymer (GMP) demonstrated that the addition of CAS promoted protein disulfide cross‐linking and decreased protein mobility during holding. Fourier transform infrared spectroscopy (FT‐IR) revealed that FCN with the addition of CAS had low decrement in α‐helix and β‐sheet during holding, indicating that starch acetates contributed to the maintenance of the gluten network structure. [ABSTRACT FROM AUTHOR]

While β,γ-unsaturated carbonyl compounds have been widely used as γC- or αC-nucleophiles, their potential αC,αC-bisnucleophilic reactivity is still underdeveloped. Herein, a phosphine-catalysed (4+1) annulation of β′-acetoxy allenoate and a β,γ-unsaturated carbonyl compound is reported, wherein β′-acetoxy allenoate is the 1,4-biselectrophilic component while the β,γ-unsaturated carbonyl compound serves as an αC,αC-bisnucleophile. The process not only provides a new reaction mode of β,γ-unsaturated carbonyl compounds under mild conditions but also broadens the scope of Lewis base-catalysed annulation of acetoxy allenoate. [ABSTRACT FROM AUTHOR]

A key requirement for the widespread commercialization of solid oxide cell (SOC) technology is to develop cost-effective oxygen electrodes with sufficiently high electro-catalytic activity and durability at intermediate temperatures (600–750 °C). Here we report a remarkable enhancement of electro-catalytic activity of cobalt-free (La0.6Sr0.4)0.98FeO3−δ (LSF) electrodes by applying a nanoengineered hybrid catalyst coating composed of nanoparticles of Ce0.85Gd0.15O2−δ (CGO) and Pr6O11via co-infiltration. Different from the conventional infiltration with a precursor of metal nitrate, here a mixture solution of colloidal CGO nanocrystals and Pr(NO3)3 is used for infiltration to enable the desired nanoengineered architecture. The resulting hybrid-catalyst-coated LSF electrode exhibits a very low polarization resistance of 0.017 Ω cm2 at 750 °C, about one order of magnitude lower than that of bare LSF (0.197 Ω cm2). Furthermore, the Ni/yttria-stabilized zirconia (YSZ) fuel-electrode-supported cell with this hybrid-catalyst-coated LSF electrode displays excellent performance in both fuel-cell and electrolysis operations, while it also offers good durability tracked over 1000 h of fuel-cell operation. The unique catalytic activity of the hybrid-catalyst-coated LSF electrode is attributed to the combined effects of accelerating oxygen surface exchange kinetics by Pr6O11 and enhancing the available surface area by the nanoporous architecture of the catalyst coating. Moreover, combined with the modification of the Ni/YSZ electrode, stable electrolysis operation at 650 °C under −0.5 A cm−2 with a voltage close to 1.3 V is achieved on a cell prepared without cobalt. This work not only opens the opportunity for applying cobalt-free oxygen electrodes in SOCs but also proposes a co-infiltration strategy to develop a highly active and robust catalyst coating by combined tuning of composition and morphology, which may also be applicable to other devices such as metal–air batteries and membrane reactors. [ABSTRACT FROM AUTHOR]