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The sluggish reaction kinetics of CO2electroreduction in perovskite-based cathodes severely limits the efficiency of solid oxide electrolysis cells (SOECs). The construction of the high-density active sites on the perovskite surface is crucial for promoting CO2electrolysis in SOEC. In this study, we explore a redox-induced redispersion strategy to produce RhOxnanoclusters uniformly anchored on a Sr2Fe1.45Rh0.05Mo0.5O6–δ(SFRhM) perovskite surface with a high density of 36,000 µm−2. Compared with non-uniformly distributed RhOxnanoparticles on Sr2Fe1.5Mo0.5O6–δ(RhOx/SFM) prepared by a conventional impregnation process, the successive reduction and oxidation treatment first exsolves the highly dispersed RhFe alloy nanoparticles on SFRhM and then selectively dissolves the iron species in the RhFe alloy nanoparticles into the bulk of SFRhM, resulting in fully exposed RhOxnanoclusters uniformly anchored on the SFRhM surface (RhOx@SFRhM). Electrochemical measurements and density functional theory calculations indicate that the high-density RhOx@SFRhM interfaces promote CO2adsorption and activation during CO2electrolysis, thus leading to improved electrocatalytic activity and stability compared to that of its SFRhM and RhOx/SFM counterparts.

Rational design of highly stable and active metal catalysts requires a deep understanding of metal–support interactions at the atomic scale. Here, ultrathin films of FeO and FeO2–xgrown on Pt(111) are used as templates for the construction of well-defined metal nanoclusters. Periodic arrays of Cu clusters in the form of monomers and trimers are preferentially located at FCC domains of FeO/Pt(111) surface, while the selective location of Cu clusters at FeO2domains is observed on FeO2–x/Pt(111) surface. The preferential nucleation and formation of well-ordered Cu clusters are driven by different interactions of Cu with the Fe oxide domains in the sequence of FeO2-FCC > FeO-FCC > FeO-HCP > FeO-TOP, which is further validated by density functional theory calculations. It has been revealed that the p-band center as a reactivity descriptor of surface O atoms determines the interaction between metal adatoms and Fe oxides. The modulated metal-oxide interaction provides guidance for the rational design of supported single-atom and nanocluster catalysts.

Construction of inverse oxide/metal model catalyst with specific chemical composition and interfacial structure is essential for clarifying their structure–performance relationship. This work describes the structural evolution of Mn–Au surface alloy and two-dimensional manganese oxide (MnOx) islands on Au(111) surface under different treatment conditions. By employing near-ambient pressure scanning tunneling microscopy and X-ray photoelectron spectroscopy, we can obtain four different MnOxstructures. Among them, double-layer square lattice Mn3O4(001) and monolayer parallelogram-shaped Mn3O4are prepared by postannealing Mn–Au surface alloy in “oxygen-poor” and “oxygen-rich” regimes, respectively. Annealing the monolayer parallelogram-shaped Mn3O4in vacuum to 700 K produces a double-layer structure consisting of Mn3O4top layer and MnO(111) bottom layer, while double-layer MnO(111) is formed after annealing in vacuum to 800 K. Our study lays the foundation for exploring the catalytic properties of inverse manganese oxide/metal model catalysts.

In hydrothermal condition, mineralizer (Na2CO3) reacted with Cr(VI)-contained minerals (hydrocalumite and calcite). The hydrocalumite transformed into calcite and the calcite crystals grew into particles with large size and complete surface, so that Cr(VI) was released and departed from the minerals.

Structural evolution of solid catalyst surfaces induced by direct exposure to reaction gas has been extensively studied and is well understood. However, whether and how subsurface atomic structures are affected by the reaction atmosphere require further exploration. In this work, our results confirm that Cu clusters supported on FeO/Pt(111) (Cun/FeO/Pt) transform into surface CuCO complexes (CuCO/FeO/Pt) with exposure to CO at 78 K. Surprisingly, Cu clusters on Pt(111) buried under monolayer FeO film (FeO/Cun/Pt) can also transform into surface CuCO complexes on FeO/Pt(111) upon CO adsorption at 150 K. The place exchange of surface and subsurface Cu atoms at the FeO/Pt(111) surface can be mediated by exposing to CO at 150 K and keeping in ultrahigh vacuum at 300 K, alternatively. Calculation results reveal that CO adsorption induces restructuring of the FeO film above the Cu clusters, generating a diffusion channel for Cu atoms to pass through the FeO film and form surface CuCO, while Cu atoms remaining at the FeO–Pt interface are more thermodynamically favored without CO. Our work suggests that buried subsurface atoms may be involved in strong restructuring processes driven by reaction gas, which could strongly influence the catalytic performance.

As one of the primary members of SWI/SNF chromatin remodeling complexes, ARID1A contains frequent loss-of-function mutations in many types of cancers. However, the molecular mechanisms underlying ARID1A deficiency in cancer biology remain to be investigated. Using breast cancer as a model, we report that silencing ARID1A significantly increased cellular proliferation and migration. Mechanistically, primarily functioning as a transcriptional repressor, loss of ARID1A profoundly alters histone modifications and the transcriptome. Notably, ARID1A inhibited the expression of a long non-coding RNA, UCA1, by regulating chromatin access of the transcription factor CEBPα. Restoration experiments showed that UCA1mediates the functions of ARID1A that induces loss of cellular proliferation and migration. Together, our findings characterize ARID1Aas a key tumor-suppressor gene in breast cancer through cooperation with CEBPα, and loss-of-function mutations of ARID1A activates UCA1.

Filtration failure occurs when filter media are blocked by accumulated solid particles. Suitable operating conditions were investigated for cake cleaning by partial oxidation of filter-cake particles (FCPs) during biomass gasification. The mechanism of the FCP partial oxidation was investigated in a ceramic filter and by using thermogravimetric analysis through a temperature-programmed route in a 2 vol % O2–N2environment. Partial oxidation of the FCPs in the simulated product gas environment was examined at 300–600 °C in a ceramic filter that was set and heated in a laboratory-scale fixed reactor. Four reaction stages, namely, drying, preoxidation, complex oxidation, and nonoxidation, occurred in the FCP partial oxidation when the temperature increased from 30 to 800 °C in a 2 vol % O2–N2environment. Partial oxidation was more effective for FCP mass loss from 275 to 725 °C. Experimental results obtained in a ceramic filter indicated that the best operating temperature and FCP loading occurred at 400 °C and 1.59 g/cm2, respectively. The FCPs were characterized before and after partial oxidation by Fourier-transform infrared spectroscopy, scanning electron microscopy, and Brunaeur–Emmett–Teller analysis. Fourier-transform infrared spectroscopy analysis revealed that partial oxidation of the FCPs can result in a significant decrease in C–Hn(alkyl and aromatic) groups and an increase in CO (carboxylic acids) groups. The scanning electron microscopy and Brunaeur–Emmett–Teller analyses suggest that, during partial oxidation, the FCPs underwent pore or pit formation, expansion, amalgamation, and destruction.

The paper introduces a design scheme for the Extra High Voltage (EHV) transformer condition on-line monitoring system, which is based on the collection and analysis of the transformer winding and core vibration signals. This system is composed of vibration acceleration signal sensors and the signal analyzing computer where the collected vibration signal is saved and processed. The analyzing computer can accomplish the missions of data acquisition control, data analysis and the historical data query. Vibration characteristic values of transformer winding and core include peak to peak value, spectrum, kurtosis, and the amplitude 100Hz component and its higher harmonic components. They are extracted, and the characteristic trend curves are drawn by data analysis, so that EHV transformer on-line monitoring and fault diagnosis are accomplished.

During the traditional collaborative filtering recommendation algorithm be impacted by itself data sparseness problem. It can not provide accurate recommendation result. In this paper, Using traditional collaborative filtering algorithm and the concept of similar level, take advantage of the idea of data populating to solve sparsity problem, then using the Weighted Slope One algorithm to recommend calculating. Experimental results show that the improved algorithm solved the problem of the recommendation results of low accuracy because of the sparse scoring matrix, and it improved the algorithm recommended results to a certain extent.

The existing alkaline batteries which businesses are unwilling to recycle can only be discarded after used, resulting in a lot of environmental problems. The crust of batteries is made of special steel which can be used repeatedly costing the 1/3 total costs. Batteries are divided into three parts: steel, core, and bottom closures. Thread at the bottom of steel corresponds with the screw thread at the bottom of the closures. As long as screw off closures, load the core, the battery can be used again. The whole process is simple. Creative design has advantages on the structure and energy, environment and energy, economic and cost, greatly improving the recovery efficiency, reducing the cost of recycling and environmental pollution, and has huge economic, social, environmental benefits.

By observing rock thin sections, starting from the analysis on rock samples, mercury injection curves, casting thin sections and scanning electron microscopy, a detailed study of under Jurassic Badaowan Formation of the North Lake Oilfield heterogeneity in terms of content is done for the prediction and evaluation of favorable reservoir.

The Dopamine-modified multiwalled carbon nanotubes (MWNT-Dopa) were synthesized by chemical reaction between dopamine (Dopa) and multiwalled carbon nanotubes which oxidazed by mixed-acid (MWNT-COOH). The structure of MWNT-Dopa were analyzed by Fourier transform infrared spectroscopy (FT-IR), Thermogravimetric (TG), Transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS) techniques and the dispersity of MWNT-Dopa were studied by Dispersion stability analyzer. The results show that dopamine has been grafted on multiwalled carbon nanotubes successfully, and a dopamine layer which wraps on the surface of multiwalled nanotubes make multiwalled nanotubes have outstanding dispersity in water.

Corrugated-arch Metal Roof has anisotropic properties because of transverse small corrugations covering the surface of the structure. Thus the panels should be considered as orthotropic plates for more accurate analysis. Based on the principle of stressed skin diaphragm, elastic constants of Corrugated-arch Metal Roof with corrugations are analyzed using equivalent methods; the formulas for equivalent elastic constants are produced and the simplified calculation model is established. The stability of the structure is analyzed and evaluated by use of the finite element method. The results are compared with experimental results, and the method of equivalent analysis is validated. The results indicate that the theoretical bearing capacity is determined by overall stability under full-span and half-span loading without considering the initial defects. Through the equivalent analysis, the length and depth of corrugations are main factors affecting the equivalent elastic constants. Design recommendations are finally presented.

In this paper, the influence of different sintering temperatures on the microstructure, density, shrinkage and final phase content of hydroxyapatite-zirconia (HA-ZrO2) composites was studied. Composites of hydroxyapatite with 3 mol% Y2O3 stabilized zirconia with MgO were sintered between 1100 ˚C and 1400 ˚C. The reaction and the transformation of phases were investigated by X-ray diffraction and FTIR spectroscopic measurements. Those results indicated that the processes of HA dehydroxylation were found, the mean grain size of the sample sintered was varied from 1.2 µm to 5.3 µm. Dimension shrinkage increased to 0.24% as the sintered temperature increased from 1100 ˚C to 1400 ˚C, the bulk density increased monotonically to 95.6% with increasing temperature up to 1400 ˚C.

Encapsulation of metal nanoparticles by support-derived materials known as the classical strong metal–support interaction (SMSI) often happens upon thermal treatment of supported metal catalysts at high temperatures (≥500 °C) and consequently lowers the catalytic performance due to blockage of metal active sites. Here, we show that this SMSI state can be constructed in a Ru–MoO3catalyst using CO2hydrogenation reaction gas and at a low temperature of 250 °C, which favors the selective CO2hydrogenation to CO. During the reaction, Ru nanoparticles facilitate reduction of MoO3to generate active MoO3–xoverlayers with oxygen vacancies, which migrate onto Ru nanoparticles’ surface and form the encapsulated structure, that is, Ru@MoO3–x. The formed SMSI state changes 100% CH4selectivity on fresh Ru particle surfaces to above 99.0% CO selectivity with excellent activity and long-term catalytic stability. The encapsulating oxide layers can be removed via O2treatment, switching back completely to the methanation. This work suggests that the encapsulation of metal nanocatalysts can be dynamically generated in real reactions, which helps to gain the target products with high activity.

Abstract: Lichens are abundant with functional groups that are capable of adsorbing dissolved metals in moisture and intercepting suspended particles in the atmosphere. Using lichen chemistry as an indicator is a prominent method of assessing a long-term baseline of atmospheric quality. This study collected foliose lichens, Parmeliasp., from an area with intensive post-volcanic activity (Tatun Volcano Group) and a deep mountain trail (Nan-ao Trail) in northern Taiwan. The geochemical results show that the lichens from Nan-ao have much higher enrichment factors (EFs) for most metals than those from the Tatun Volcano Group, which revealed that the geochemistry of Nan-ao lichens is dominated by interception of suspended particles rather than absorption of lichen surface. In addition, the fact that no Eu-negative anomaly (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${{\text{Eu}}/{\text{Eu}}^{*} }$$\end{document}≈ 1.0) can be observed in the normalized patterns of rare earth elements of lichens from Nan-ao reconfirms the derivation. In contrast, lichens from the Tatun Volcano Group are characterized by lower enrichment factors of metals, evident from Ce-negative and Eu-positive anomalies (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${{\text{Ce}}/{\text{Ce}}^{*} }$$\end{document}< 0.6 and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${{\text{Eu}}/{\text{Eu}}^{*} }$$\end{document}> 1.0), which implies that the lichen chemistry may be principally established by the chemical adsorption of functional groups on the lichen surface. In addition, the extraordinary enrichment factors of Ca, Mg, Na, and K of lichens near the northern coast (EF > 10) prove the involvement of seawater aerosol on the atmospheric chemistry. The lead isotopic compositions reveal that unleaded gasoline could be the dominant source of lead for Nan-ao lichens (207Pb/206Pb > 0.86 and 208Pb/206Pb < 2.105), while the local andesite provides the lead to lichens from the Tatun Volcano Group. However, the Tatun Volcano Group is very close to Taipei City, with all kinds of anthropogenic activities, which also contribute a considerable amount of lead to the atmosphere. Research highlights:

The geochemistry of lichens from volcanic area shows depletion of transitional metals and Ce-negative anomaly, which demonstrates the geochemical fractionation during transportation in atmosphere.

The geochemistry of lichens from non-volcanic area is characterized by high EFs for most elements and no Ce-negative anomaly, which demonstrates lichens inherit the chemical properties from suspended particles.

The lead isotopic compositions reveal that unleaded gasoline could be the dominant source of lead for lichens from non-volcanic area, while the local andesite provides the lead to lichens from the volcano area.

Oxygen vacancies (Vos) play a vital role in the physical and chemical properties of oxide materials and their applications. Because Vos are first produced on oxide surfaces, it has been often recognized that they are richer at the top surface than at the subsurface or bulk region. Here the depth distribution of Vos in reduced manganese oxide (MnOx) films has been studied by a combination of ion-sputtering treatment and variable-angle X-ray photoelectron spectroscopy measurement. The density of Vos on the top surface is determined to be ∼8% lower than that in the subsurface region after reduction treatment of the oxide in CO at 573 K. Density functional theory calculations show that lattice oxygen atoms in the bulk tend to migrate and fill into the Vos on the top surface with a barrier of 0.94 eV at most. The stability of Vos in the bulk is higher than that on the surface via a reduced Mn3O4skeleton, which can be reflected by the energy of oxygen filling at the Vo.

Pd single site-anchored La0.5Sr0.5FeO3-δ-Ce0.8Sm0.2O2-x(Pd-LSF(SDC)) cathode is constructed for CO2electrolysis in solid oxide electrolysis cells. The decoration of Pd species on LSF greatly improves CO2electrolysis performance with 65.7% enhancement in current density at 1.6 V compared with the LSF counterpart. Electrochemical and density functional theory calculation results suggest that the Pd species are atomically anchored on the LSF phase. The coordinatively unsaturated Pd with oxygen vacancies facilitates the CO2dissociative adsorption, electron transfer and mass transport, thus greatly decreases the polarization resistance of the cathode and promotes the CO2electrolysis performance. This work provides an effective strategy to design the supported single site catalyst for high-temperature CO2electrolysis.