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Nitrogen-doped porous carbon spheres (NCS) with NixCo3O4 composite were derived from a metal–organic framework through a heat treatment.

Although evidence for cultural variants in facial expression decoding is accumulating, the other-race effect in facial expression processing and its neural correlates are still unclear. We investigated this question with a fully balanced design, in which a group of East Asian and a group of European Caucasian women categorized pictures of sad, happy, angry, and neutral facial expressions posed by individuals of their own-race and the other-race. Results revealed a disadvantage in categorizing expressions of anger in other-race faces in both samples, and for sad expressions in the European sample only. Partially consistent, East Asian participants showed longer latency of the N170 component in the event-related potential (ERP) and European Caucasian participants showed larger N170 amplitudes to other-race faces. The late positive complex in the ERP was less distinguishable among other-race facial expressions. Therefore, the present study observed an other-race effect in early and late stages of face processing, reflecting less efficient structural encoding and less elaborate processing for other-race than own-race faces.

Here, a simple, economical one-step doping strategy is adopted to prepare N, S co-doped graphene hollow spheres (NSGHS). The NSGHS exhibits remarkable oxygen-reduction-reaction (ORR) activity with a high half-wave potential (E1/2) of 0.847 V vs. RHE and considerable long-term stability. When applied as anode materials for sodium-ion batteries (SIBs), it could deliver a high reversible capacity of 385 mAh g−1 at 500 mA g−1, excellent rate performance of 308 mAh g−1 at even 20 A g−1 and superior cycling performance at 10 A g−1 during 5000 cycles with negligible capacity fade. DFT calculation reveals that the doping of N and S endows the surrounding carbon with high positive charge and spin density, respectively, making them be highly active ORR catalytic sites except for S itself. Despite the possible oxidization of C–S–C active sites, the rest C atoms of NSGHS will still hold a considerably high catalytic activity superior to those of mono-doped or undoped cases. In addition, S doping will improve the binding between Na and graphene substrate to get a high capacity and N doping effectively curbs the rising of oxygen levels and oxidization of S in C–S–C active sites, thus the excellent stability for ORR and SIBs. © 2021 Elsevier Ltd

The atmospheric pressure dielectric barrier discharge (DBD) plasma is introduced to prepare a unique NiFe/NiSe2 heterostructure with abundant oxygen vacancies greatly promoting OER/ORR bifunctional electrocatalytic activity.

NiFe alloy NPs anchored in NGHS wrapped with self-grown NCNTs with a three-dimensional architecture was constructed successfully for ORR/OER bifunctional catalysis.

A rapid, facile, green and controllable electrodeposition method is reported for the growth of SeOx films on the surface of Ni–Fe–selenide nanosheets, which are used as highly active and stable electrocatalysts for the OER.

La/Fe co-doped Co3O4 nanoparticles supported on aminated CNTs have shown high catalytic activities for the ORR and OER. The specific La/Fe co-doped structure of Co3O4 is shown to be the main origin of their high catalytic activities.

An in situ thermal exclusion approach is reported for the synthesis of carbon coated Sb-ATO hetero-NPs deposited on MWCNTs. The specific structure endows it with superior rate capacities and excellent cycling stabilities towards Na+ storage.

Two diiron toluene-3,4-dithiolate complexes with a phosphine ligand or a phosphite ligand were prepared and characterized. Treatment of complex [Fe2(CO)6{µ-SC6H3(CH3)S}] (1) with one equivalent of ...

Abstract. In order to explore the time course of the influence of gender words semantic satiation on facial gender information processing, the semantic satiation paradigm was used to induce semantic satiation by presenting Chinese gender words “男, 女 (Male, Female)” for a long duration (25 s), with conjunction words “及(And), 且(Moreover)” served as the baseline (the Chinese words and their English translations do not completely equal in terms of pronunciation, form, and sense). Participants were asked to judge whether the two simultaneously presented faces (Experiment 1) or two successively presented faces (Experiment 2) were of the same gender. The results of Experiment 1 showed that the response time in semantic satiation condition was significantly longer than that of the baseline condition. The event-related potential (ERP) results of Experiment 2 showed that the peak amplitude of P1 component in semantic satiation condition was significantly smaller than that of the baseline condition in the early stage of face processing; N170, a specific component of face perception, in semantic satiation condition was significantly larger than that of the baseline condition. The average amplitude of LPC in semantic satiation condition was significantly smaller than that of the baseline condition. This study shows that facial gender information processing is affected by its semantic contextual information. The inhibition effect of gender word semantic satiation on facial gender information processing starts at the attention orientation stage, then continues to the face structural encoding stage, and eventually ends at the advanced cognitive response stage.

In this report, we describe the preparation of two diiron butane-1,2-dithiolate pentacarbonyl complexes with tris(3-fluorophenyl)phosphine or tris(3-chlorophenyl)phosphine as mimics for the active ...

An approach, i.e., atmospheric-pressure nonequilibrium oxygen plasma jet technology, has been reported for the first time to in situ prepare ultrathin nonstoichiometric nickel oxide layers with mix...

Two diiron ethane-1,2-dithiolate complexes were prepared and structurally characterized. Reactions of the parent complex [Fe2(CO)6(μ-SCH2CH2S)] (1) with tris(4-trifluoromethylphenyl)phosphine or tr...

As a clean energy carrier, hydrogen has priority in decarbonization to build sustainable and carbon-neutral economies due to its high energy density and no pollutant emission upon combustion. Electrochemical water splitting driven by renewable electricity to produce green hydrogen with high-purity has been considered to be a promising technology. Unfortunately, the reaction of water electrolysis always requires a large excess potential, let alone the large-scale application (e.g., >500 mA cm−2 needs a cell voltage range of 1.8–2.4 V). Thus, developing cost-effective and robust transition metal electrocatalysts working at high current density is imperative and urgent for industrial electrocatalytic water splitting. In this review, the strategies and requirements for the design of self-supported electrocatalysts are summarized and discussed. Subsequently, the fundamental mechanisms of water electrolysis (OER or HER) are analyzed, and the required important evaluation parameters, relevant testing conditions and potential conversion in exploring electrocatalysts working at high current density are also introduced. Specifically, recent progress in the engineering of self-supported transition metal-based electrocatalysts for either HER or OER, as well as overall water splitting (OWS), including oxides, hydroxides, phosphides, sulfides, nitrides and alloys applied in the alkaline electrolyte at large current density condition is highlighted in detail, focusing on current advances in the nanostructure design, controllable fabrication and mechanistic understanding for enhancing the electrocatalytic performance. Finally, remaining challenges and outlooks for constructing self-supported transition metal electrocatalysts working at large current density are proposed. It is expected to give guidance and inspiration to rationally design and prepare these electrocatalysts for practical applications, and thus further promote the practical production of hydrogen via electrochemical water splitting.

Structural features are important factors determining the performance of electrode materials for alkaline metal (Li, Na, and K) storage. In this work, we report a fascinating Kirkendall-effect-based method for the synthesis of a spindle-like FeP@C composite with a hierarchical structure comprising carbon-coated hollow FeP sub-nanoparticles (S-HFeP@C). In such a unique structure, the interconnected carbon network and intimate C/FeP contact allow for the ready transfer of charge during redox reactions. The hollow structure of the FeP nanoparticles and their thin walls allow for easy ion diffusion and satisfactory alleviation of the overall strain of FeP, endowing S-HFeP@C with fast reaction kinetics, satisfactory utilization of active material, and excellent structural robustness upon redox reaction. Enhanced performance was observed for Li, Na, and K storage by S-HFeP@C, consisting of a high specific capacity, excellent rate capabilities, and satisfactory cycling stability.

On account of multiple electron exchange reaction processes, transition metal sulfides with high specific capacities are considered as promising electrode materials for sodium-ion batteries. However, their poor electrical conductivity and fragile structure always result in a poor cycling performance and a low rate capability, which hinder their practical applications. Herein, based on a spatially-microscopic-confined strategy, double-layer carbon-encapsulated MoS2 (C@MoS2@C) nanocubes were synthesized using nitrogen-doped hollow carbon nanocubes as a precursor, and these were used as anode materials. Due to the self-healing capacity of MoS2 during the charging process, the microstructure of MoS2 was effectively restored and the electrode microstructure was stably maintained under ultra-long-term cycling. With these synergistic effects, the C@MoS2@C anode exhibited a remarkable reversible capacity of 163.9 mA h g−1 after 10 000 cycles even at an ultrahigh current density (10 A g−1), with capacity fading as low as 0.004% per cycle. The current findings of the microscopic spatially confined strategy could provide a promising approach for the rational design of high-capacity electrodes.

It is generally believed that metals which are unalloyable with Li are not active for Li storage. This work, however, demonstrates that transition metals with unoccupied 3d orbitals are usable as anode materials for Li storage although they are unalloyable with Li. Specifically, we synthesize spindle-shaped Fe@C (S-Fe@C) by the calcination of an Fe based metal–organic framework, which comprises carbon coated Fe subnanoparticles with an interconnected carbon network. When used in LIBs, S-Fe@C can exhibit a stable reversible capacity of 967.3 ± 16.2 mA h g−1 at 100 mA g−1. More interestingly, when S-Fe@C with smaller Fe nanoparticles and more spacing between the Fe nanoparticles and carbon shell is used as the anode for LIBs, the stable reversible capacity can reach up to 1091.9 ± 17.6 mA h g−1 at 100 mA g−1 after 100 cycles. The in operando XRD patterns exclude the contribution of capacities from the alloying between Fe and Li. DFT calculations indicate that the unoccupied 3d orbitals of Fe atoms can accept electrons from Li, which makes the surface of Fe nanoparticles highly active for Li adsorption. The Li adsorption can be multi-layered. Our findings can well explain why some transition metal oxides can exhibit extra capacities beyond their theoretical capacities.

Microbial fuel cells, an emerging technology has been paid a great attention in recent years, due to its unique advantages in treating wastewater to portable water, together with the generation of useful electricity, with the help of bio-active anodes and electrochemical cathodes, simultaneously. When applying this technology in a practical scale, the indigenous bacteria present in the wastewater catalyze the breakdown of organic matter in the anode compartment, with generation of electrons and in the cathode compartment an oxidant, usually the oxygen present in the air, take the electron and reduce to water (oxygen reduction reaction, ORR). An ideal ORR catalyst should be highly active, durable, scalable, and most importantly it should be cost effective. Generally, platinum-based catalyst is utilized, however, due to the high cost of Pt based catalysts, many cheap, cost effective catalyst have been identified as efficient ORR catalyst. Carbon based catalysts known to possess good electronic conductivity, desirable surface area, high stability, together when doped with heteroatoms and cheap metals is found to remarkably enhance the ORR activity. Although a lot of research has been done in view of developing carbon based cheap, cost-effective catalysts, still their collective information has not been reviewed. In this article we anticipate reviewing various non-precious metal and metal-free catalysts that are synthesized and investigated for MFCs, factors that affect the ORR activity, catalyst designing strategies, membranes utilized for MFCs, together with the cost comparison of non-precious and metal-free catalysts with respect to Pt based catalysts have been summarized. We anticipate that this review could offer researchers an overview of the catalyst developed so far in the literatures and provides a direction to the young researchers.

A plasma assisted phosphorization method has been developed for preparation of multi-phase materials with rich crystalline interfaces and oxygen vacancies. Specifically, P-NiMoP nanorods (NRs) comprising tri-phases of MoP2, Ni3P and MoO2 have been synthesized by plasma-assisted phosphorization of NiMoO4 NRs. The specific features of the plasma technique provide P-NiMoP NRs with rich crystalline interfaces and oxygen vacancies in MoO2. P-NiMoP NRs are demonstrated to be a stable and efficient catalyst for the hydrogen evolution reaction (HER). They only need overpotentials of 3 and 162 mV to drive current densities of 10 and 150 mA cm−2, both of which are lower than those of Pt/C. The DFT calculations indicate that the tri-phase structure with rich crystalline interfaces and oxygen vacancies plays an important role in the high catalytic activity of P-NiMoP NRs. It promotes a strong electronic coupling between MoP2, Ni3P and MoO2, which facilitates H2O adsorption and dissociation and reduces the |ΔGH*| value.

Objectives: The objective of this study was to determine the relationship between the levels of stress biomarkers in cord blood and pre-eclampsia (PE) in a hospital-based population of pregnant patients and evaluate the effects on pregnancy outcomes. Design: This was an observational, case-control study. Participants/Materials, Setting, Methods: This case-control study included 282 patients with severe PE and 534 women with normal pregnancy. The umbilical cord was collected at delivery and tested for malonaldehyde (MDA), reactive oxygen species (ROS), superoxide dismutase, and homocysteine (Hcy) analysis. We performed a univariate general linear regression model analysis to control potential confounders and determined the underlying influencing factors for high MDA and ROS. A receiver operating characteristic curve analysis was conducted to determine the cutoff values for identifying severe PE. Further, the severe PE group was divided into the low- or high-MDA and low- or high-ROS subgroups according to the cutoff values. Finally, we created logistic regression models to estimate the adjusted odds ratio for each perinatal outcome in the high-MDA and high-ROS subgroup. Results: The levels of MDA and ROS levels were higher in women with severe PE than in normotensive pregnant patients. However, when adjusted for cord blood Hcy levels, the difference was insignificant. Additionally, both MDA (r = 0.359, p < 0.001) and ROS (r = 0.473, p < 0.001) were positively correlated with the cord blood Hcy level. The areas under the curve of MDA and ROS levels were 0.65 (95% confidence interval [CI]: 0.60–0.69) and 0.88 (95% CI: 0.86–0.90), respectively. Higher MDA and ROS levels were associated with increased risks of a low Apgar score, admission to the NICU, and assisted ventilation for the newborn. Limitations: The study design led to the exclusion of several participants. Conclusions: Increased levels of oxidative stress markers in the cord blood might be significantly associated with negative effects on newborns. High levels of Hcy in the cord blood might be associated with elevated MDA and ROS concentrations in women with severe PE.

Rechargeable solid-state Zn-air batteries (ZABs) have drawn attractive prospects for flexible wearable electronic devices; however, their practical application is severely hindered due to the slugg...

Biomimics for the active site of [FeFe]-hydrogenases, have been synthesized and characterized. Treatment of [Fe2(CO)6{μ-SCH2CH(CH3)S}] (1) and phosphine ligands tris(2-furyl)phosphine, tri(m-tolyl)phosphine, bis(diphenylphosphino)methane (dppm), or 1,2-bis(diphenylphosphino)benzene (dppbz) with Me3NO·2H2O as the decarbonylation agent afforded the corresponding phosphine-containing derivatives [Fe2(CO)5(L){μ-SCH2CH(CH3)S}] (L = P(2-C4H3O)3, 2; P(3-C6H4CH3)3, 3; Ph2PCH2PPh2, 4) and [Fe2(CO)4{κ2-(Ph2P)2(1,2-C6H4)}{μ-SCH2CH(CH3)S}] (5) in moderate to good yields. The new complexes 2‒5 have been structurally characterized by elemental analysis, IR, NMR spectroscopy, and further confirmed by X-ray diffraction analysis. The electrochemistry of complexes 2‒5 have been investigated by cyclic voltammetry, showing that they can catalyze the reduction of protons to H2 in the presence of HOAc.

Herein, we report the preparation and characterization of two diiron carbonyl complexes with ethyldiphenylphosphine or dicyclohexylphenylphosphine. Me3NO-driven decarbonylation of complex [Fe2(CO)6...