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Segregation of interface elements is the main factor affecting the corrosion activity of microareas around Al2O3 inclusions rather than galvanic corrosion. In this work, the effects of segregation of Cu, V, Ni, Mo, B, and P elements on the interfacial bonding strength and microareas corrosion activity around Al2O3 inclusions are analyzed in detail using 3D atomic probe and first‐principles calculations. In the results, it is shown that Cu, V, Mo, B, and P elements reduce the stability of the α‐Fe/Al2O3 interface. In addition, the segregation of Cu, V, Mo, B, and P elements at the interface also enhances the adsorption capacity of Cl and ultimately improves the microarea corrosion activity around Al2O3 inclusions. Ni element can enhance the stability of α‐Fe/Al2O3 interface, and the segregation of Ni element at the interface weakens the adsorption capacity of Cl and ultimately reduces the microarea corrosion activity around Al2O3 inclusions. [ABSTRACT FROM AUTHOR]

Global climate warming could affect the methane (CH4) and nitrous oxide (N2O) fluxes between soils and the atmosphere, but how CH4 and N2O fluxes respond to whole‐soil warming is unclear. Here, we for the first time investigated the effects of whole‐soil warming on CH4 and N2O fluxes in an alpine grassland ecosystem on the Tibetan Plateau, and also studied the effects of experimental warming on CH4 and N2O fluxes across terrestrial ecosystems through a global‐scale meta‐analysis. The whole‐soil warming (0–100 cm, +4°C) significantly elevated soil N2O emission by 101%, but had a minor effect on soil CH4 uptake. However, the meta‐analysis revealed that experimental warming did not significantly alter CH4 and N2O fluxes, and it may be that most field warming experiments could only heat the surface soils. Moreover, the warming‐induced higher plant litter and available N in soils may be the main reason for the higher N2O emission under whole‐soil warming in the alpine grassland. We need to pay more attention to the long‐term response of greenhouse gases (including CH4 and N2O fluxes) from different soil depths to whole‐soil warming over year‐round, which could help us more accurately assess and predict the ecosystem‐climate feedback under realistic warming scenarios in the future. [ABSTRACT FROM AUTHOR]

Cu is an austenite‐forming element in duplex stainless steel, and the precipitation of Cu‐rich phase can improve the strength of the alloy. However, the role of Cu element in the corrosion resistance of stainless steel is widely controversial. Herein, the effects of different Cu content on the formation of inclusions and the pitting resistance of duplex stainless steel are studied by using potentiodynamic anodic polarization test, immersion corrosion, scanning electron microscope, and electron probe microanalysis. The results show that the pitting potential decreases significantly with the increase of Cu content, which greatly reduces its ability to resist Cl− corrosion. The reason is that Cu increases the driving force for the formation of Al‐containing oxides, which increases the number and size of Al‐containing inclusions formed in the process of melting and solidification. At the same time, Cu promotes the formation of Cr‐depleted zone, which promotes the formation of microcracks and pitting corrosion between steel matrix and inclusions in duplex stainless steel. [ABSTRACT FROM AUTHOR]

The gap between the rich and the poor is growing, and moral judgements between the rich and the poor will greatly affect their interaction and social stability. Based on subjective group dynamics theory, the current research leveraged two studies to test the interactive effect between self social class and target social class on moral judgements, and explored one important boundary of this interactive effect. The results of Study 1 showed that participants tended to make a stricter moral judgement on a target of the same social class as themselves than on a target of a different social class. The results of Study 2 further showed that people from the same social class and the same university judged each other with stricter moral standards; in contrast, people from the same social class but different universities did not use stricter moral standards. Therefore, individuals would make stricter moral judgements on people from the same social class as themselves, but make looser judgements on people from different social classes. This phenomenon only occurred when the participants and the target came from the same well‐defined groups instead of different well‐defined groups. Finally, the implications and limitations of this research were discussed. [ABSTRACT FROM AUTHOR]

Rare earth elements have unique outer electronic structure, variable valence, and strong chemical activity; however, their occurrence state in the rust layer and influence on the invasion state of corrosion atoms are still unclear. Herein, using a combination of experiment and first‐principles calculation, the occurrence state of La in the rust layer of low‐alloy high strength steel, the phase composition, compactness and stability of the rust layer, and the invasion state of corrosion atoms before and after La alloying are studied. The results show that La exists in the corrosion products in the form of a solute atom. La increases the concentration of corrosion‐resistant elements Cr and Mo in the rust layer but does not change the phase composition. La is conducive to stabilizing Cl atoms in α‐FeOOH and β‐FeOOH, so as to protect the steel matrix from Cl. La atoms inhibit the dissolution of Cl atoms into γ‐FeOOH and Fe3O4 structures and hinder their formation. [ABSTRACT FROM AUTHOR]

The alpine meadow ecosystem on the Qinghai–Tibetan Plateau (QTP) is very sensitive to warming and plays a key role in regulating global carbon (C) cycling. However, how warming affects the soil organic carbon (SOC) pool and related C inputs and outputs in alpine meadow ecosystems on the QTP remains unclear. Here, we combined two field experiments and a meta‐analysis on field experiments to synthesize the responses of the SOC pool and related C cycling processes to warming in alpine meadow ecosystems on the QTP. We found that the SOC content of surface soil (0–10 cm) showed a minor response to warming, but plant respiration was accelerated by warming. In addition, the warming effect on SOC was not correlated with experimental and environmental variables, such as the method, magnitude and duration of warming, initial SOC content, mean annual temperature, and mean annual precipitation. We conclude that the surface SOC content is resistant to climate warming in alpine meadow ecosystems on the QTP. [ABSTRACT FROM AUTHOR]

Miscanthus spp. are increasingly cultivated in cropland worldwide due to their bioenergy potential and multiple ecological services. Effects of long‐term cropland‐to‐Miscanthus conversion without N fertilizer on soil microbiome and N cycling largely remain unknown. We aimed to explore the effects of Miscanthus conversion on soil microbiome and N cycling over a 15‐year period. We analyzed diversity, composition, and abundance of bacterial and archaeal communities using 16S rRNA amplicon sequencing, and abundances of N‐cycling‐related genes using quantitative polymerase chain reaction of 0–10 cm soils collected from bare land, cropland, 10‐year Miscanthus × giganteus, and 15‐year Miscanthussacchriflorus land in Beijing. Conversion decreased soil sand and micro‐aggregate proportion, nitrate N (NiN), available phosphorus levels, conductivity, temperature, and pH, while increasing proportion of soil clay and macro‐aggregate (MAA), soil organic C (SOC), available N (AN), exchangeable Mg2+ (EMg2+), and available potassium (AK) contents as well as microbial C/N. Consequently, diversity, composition, and abundance of soil bacterial community exhibited larger changes than those values of archaeal community after conversion. Soil AP, EMg2+, AK, and SOC were key factors in shifting microbiome from the cropland to Miscanthus pattern. Moreover, abundances of bacterial and archaeal communities and the N fixer gene nifH increased, whereas that of the bacterial ammonia monooxygenase gene decreased. The copies of other N‐cycling‐related genes in the two Miscanthus lands seemed similar to those values of cropland. The nifH copies negatively correlated with soil NiN and positively correlated with AN, EMg2+, ECa2+, SOC, AK, and MAA. We conclude that changes in soil microbiome pattern induced by the variation of soil properties enhance microbial N fixation potential, maintaining stable N levels and robust N cycling with lower N leakage risk after conversion. These results should inspire farmers and governments to large‐scale use Miscanthus on marginal cropland in Northern China. [ABSTRACT FROM AUTHOR]

Two novel copolymers PBDT-DEAITN and PBDT-DOAITN containing the same backbone of isothianaphthene (ITN) quinoidal and benzodithiophene (BDT) donor units are synthesized and their organic photovoltaic (OPV) devices are fabricated. Although these two polymers have rather low optical bandgaps, 1.52 and 1.58 eV for PBDT-DEAITN and PBDT-DOAITN, respectively, their OPV cells exhibit rather limited power conversion efficiencies of 1.25% and 1.20% under an AM1.5G simulated solar light. The reasons for the low OPV performance are investigated by structure modeling calculation. Based on this and the screening results for the representative quinoidal polymers in the literatures, a strategy of designing high- performance planar polymers based on ITN unit is proposed. [ABSTRACT FROM AUTHOR]

The particles and microstructural characteristics in the simulated heat‐affected zone (HAZ) of the Al–Ti deoxidized steel with 0.05% Ce treatment are investigated using in situ, optical, and electron microscopes and an electron backscattered diffraction analysis, and compared with the Al–Ti deoxidized steel with Ca treatment. The results reveal that the fine CeAlO3 inclusions and nanoscale (Ti, Nb)N precipitates are formed in the Ce‐bearing steel instead of the Ca–Al oxides surrounded by TiN and nanoscale (Ti, Nb)N precipitates in the Ca‐bearing steel. The nanoscale precipitates with higher density in the Ce‐bearing steel can effectively pin austenite grain boundary, and the finer austenite grain is obtained during the welding thermal cycle. The inclusions in both steels are detrimental to the acicular ferrite nucleation. Thus, the transformation from austenite to bainite occurs actively, and bainite packets with different lengthening directions divide the prior austenite into several small regions at intermediate temperature. The fine‐grained microstructure is obtained in the simulated HAZ of the Ce‐bearing steel due to the pinning effect of finer precipitates with higher density and the formation of the bainite packets with high‐angle grain boundary. [ABSTRACT FROM AUTHOR]

In the title centrosymmetric compound, C(28)H(32)N(4)O(2) (2+) 2I(-), the two midazole rings are approximately perpendicular to the central anthracene ring system [dihedral angle = 86.6 (2)°]. The ionic units are linked into a two-dimensional network parallel to (01) by C-H⋯I hydrogen bonds and π-π inter-actions involving the anthracene ring system and imidazole rings [centroid-centroid distance = 3.717 (3) Å].

In the title compound, Na(+)·4C(7)H(5)N(6) (+)·5BF(4) (-), the Na(+) ion lies on a fourfold rotation axis and one of the tetra-fluoridoborate ions lies on a site of symmetry . Each Na(+) ion is surrounded by four symmetry-related tetra-fluoridoborate ions, and is eight-coordinated by F atoms, the Na⋯F separation being 2.3956 (15) or 2.4347 (17) Å. The hexa-azaphenalenium ring system is essentially planar. In the crystal structure, the cations and anions are linked into a three-dimensional network by N-H⋯N and C-H⋯F hydrogen bonds.