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The development of highly selective homogeneous electron transfer reagents is highly desirable for synthetic chemistry. An isolable spirosilole tetra-anion described in this paper has been proved to be a promising soluble electron transfer reagent. The reduction of octaphenyl-1,1′-spirobisilole (1) with lithium resulted in the formation of the isolable spirosilole tetra-anion in good yield. The tetra-anion (2) has been characterized by nuclear magnetic resonance (NMR) and cleanly underwent electron transfer reactions with dioxygen, carbonyl groups, and transition metal halides to yield reduction products with the regeneration of 1.

To obtain a highly active, stable, and binder‐free electrode based on transition‐metal compounds for water splitting, nickel foam‐supported 3D NiMoO4 nanosheet arrays modified with 0D Fe‐doped carbon quantum dots (Fe‐CQDs/NiMoO4/NF) are synthesized. The structure characterizations indicated that 0D Fe‐CQDs are evenly dispersed onto the NiMoO4 sheets of the arrays. The contact angle analysis confirmed that the surface hydrophilia of the arrays is improved after the 0D Fe‐CQDs are deposited 3D on the NiMoO4 sheets. Here, both the activity and durability in electrochemical water splitting are significantly enhanced with the Fe‐CQDs/NiMoO4/NF catalysts. At a current density of 10 mA cm−2, the resultant Fe‐CQDs/NiMoO4/NF revealed an overpotential of only 117 mV for the hydrogen evolution reaction (HER), a relatively low overpotential of 336 mV toward the oxygen evolution reaction (OER), and a Faraday efficiency of up to 99 %. This performance can be attributed to the unique 3D nanosheet array structure, the synergistic effect, and the optimal hydrophilia for gas evolution evolved from the electrode surface. [ABSTRACT FROM AUTHOR]

Even though some recent research revealed individuals with HSA typically display enhanced processing in the early stages of emotional information processing due to hypervigilance and vulnerability to negative stimuli, it is still unclear whether social anxiety affects the time course underlying processing bias for emotional stimuli. Therefore, the present study aimed to explore the early stage of processing social threat stimuli in high social anxiety (HSA) individuals by recording RTs and EEG data in the emotional Stroop task. Behavioral data showed that the HSA group responded to the threat words faster than neutral words (i.e. negative bias), but no emotional effects in the low social anxiety (LSA) group. Although the P1 component did not show any early effects, ERP data exhibited an enhanced N170 for HSA than for LSA groups. Threat words elicited larger N170 than neutral words in the LSA group only; this emotion effect was not evident in the HSA group. These findings indicated that social anxiety modulates early processing for social threat words. This study revealed the neural mechanisms underlying early emotional processing in individuals with social anxiety, providing insights for the evaluation and intervention of social anxiety. [ABSTRACT FROM AUTHOR]

A core-shell and spherical structured Fe3O4@MnO2 nanostructure is designed and developed via a facile and low-cost two-step method. Core-shell structured Fe3O4@MnO2 with uniform morphology can be obtained after layered structured δ-MnO2 is grown on the surface of Fe3O4 nanospheres. The crystal structures and morphology of as-prepared Fe3O4@MnO2 are characterized by scanning electron microscopy, X-ray diffraction, nitrogen isotherm analysis, and transmission electron microscopy. At the current density of 0.1 A g−1, the specific capacitance of Fe3O4@MnO2 is 243.7 F g−1, and its capacitance retention is almost 100% after 3000 continuous charge/discharge cycles at current density of 1 A g−1. The excellent cycling stability and low cost make this core-shell structured Fe3O4@MnO2 a promising electrode material for practical applications in pseudocapacitors. [ABSTRACT FROM AUTHOR]

The effect of organopalygorskite (OPGS) on an intumescent flame retardant (IFR) low‐density polypropylene (PP) has been investigated using the limited oxygen index (LOI), vertical burning test (UL‐94) and thermogravimetric analysis (TGA). The results of the LOI and UL‐94 tests indicate that the addition of OPGS substantially increases the LOI value for PP/IFR at a OPGS to IRF mass ratio of 2/28 with 30 wt% of total flame retardant. In addition, the samples pass the V‐0 rating in the UL‐94 tests. The results indicate that the addition of 2.0 wt% of OPGS simultaneously increases the tensile strength and bending strength of PP/IFR. J. VINYL ADDIT. TECHNOL., 24:281–287, 2018. © 2016 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

In this work, a metastable aqueous interface was fabricated for synthesizing mesoporous and high surface area MnO 2 . When urea was used as the additive, hierarchical spheres self-organized from ultrathin nano-sheets were obtained. Its porous structure could be controlled through adjusting the urea concentration, and a maximum surface area of 407 m 2 g −1 was achieved by this method, which is larger than the reported values. Due to the porous structure and high surface area, as-prepared MnO 2 exhibited a specific capacitance of 775.4 F g −1 at a current density of 0.1 A g −1 , and exhibited a 63.5% capacitance retention when the current density was increased from 0.1 A g −1 to 5 A g −1 . Durability studies showed a 63.7% capacitance retention after 2500 cycles. The metastable interfacial reaction approach could also be extended to other alloys with large surface area and porous structure, such as CoB alloy. This method provides a simple and low-cost method to synthesize high surface area and mesoporous materials. [ABSTRACT FROM AUTHOR]

Potassium-ion batteries (PIBs) have attracted enormous attention due to the increasing lithium battery cost, but their development is still in the pre-mature stage due to the limited selection of electrodes. Herein, a free-standing current-collector-integrated electrode, composed of mixed-phase WS 2 nanosheets with nitrogen-doped multichannel carbon nanofibers (N-MCNFs) membrane, is reported for high-performance potassium ion batteries anode. Benefiting the unique multichannel carbon nanostructure as a current collector-integrated electrode as well as mixed-phase lamellar structure WS 2 for enhanced potassium ion entry, the 1T/2H-WS 2 /N-MCNFs hybrid current-collector-free anode delivers an outstanding areal capacity of 2.88 mAh cm -2 (corresponding to 411 mAh/g based on the mass of both electrode and current collector) at a current of 0.7 mA cm -2 as well as long-term cycling stability for over 1000 cycles at a high current of 14 mA cm -2 , surpassing the current state-of-art PIB anode. It is believed that our findings based on the high energy current collector integrated electrode at high mass loading would boost future research on practical metal ion batteries., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Owing to their almost similarities in size, shape, and chemical reactivity, effectively distinguishing deuteroxide (D 2 O) in water (H 2 O) remains an ongoing challenge, and the examples of a D 2 O probe are still quite scarce. Herein, since H 2 O can decrease the lifetime of a singlet oxygen as a vital intermediate and an H/D exchange in the luminescence process of porphyrins, we systematically investigated the enhanced ultraviolet-visible (UV-vis), photoluminescence (PL), and electrochemiluminescence (ECL) of water-soluble tetrakis(carboxphenyl)porphyrin (TCPP) in D 2 O. The findings showed that these luminescent properties had been greatly enhanced with the increase of the D 2 O fraction in water. Consequently, we first developed the highly facile methods of detecting D 2 O in H 2 O by the UV-vis, PL, and ECL of TCPP, respectively. Impressively, the ECL analysis exhibited a great superiority with a lower detection limit of 0.29 nM. The work not only achieves the challenging task of distinguishing between H 2 O and D 2 O but also provides a unique strategy to enhance the luminescent performance of porphyrin.

Super-resolution microscopy (SRM) imaging of the finite subcellular structures and subtle bioactivities inside organelles delivers abundant cellular information with high fidelity to unravel the intricate biological processes. An ideal fluorescent probe with precise control of fluorescence is critical in SRM technique like stimulated emission depletion (STED). Si-rhodamine was decorated with both targeting group and H + -receptor, affording the dually fluorogenic Si-rhodamine in which the NIR fluorescence was efficiently controlled by the coalescent of spirolactone-zwitterion equilibrium and PeT mechanism. The dually fluorogenic characters of the probe offer a perfect mutual enhancement in sensitivity, specificity and spatial resolution. Strong fluorescence only released in the existence of targeting protein at acidic lysosomal pH, ensured precisely tracking the dynamic of lysosomal structure and pH in living cells by STED., (© 2021 Wiley-VCH GmbH.)

To obtain a highly active, stable, and binder-free electrode based on transition-metal compounds for water splitting, nickel foam-supported 3D NiMoO 4 nanosheet arrays modified with 0D Fe-doped carbon quantum dots (Fe-CQDs/NiMoO 4 /NF) are synthesized. The structure characterizations indicated that 0D Fe-CQDs are evenly dispersed onto the NiMoO 4 sheets of the arrays. The contact angle analysis confirmed that the surface hydrophilia of the arrays is improved after the 0D Fe-CQDs are deposited 3D on the NiMoO 4 sheets. Here, both the activity and durability in electrochemical water splitting are significantly enhanced with the Fe-CQDs/NiMoO 4 /NF catalysts. At a current density of 10 mA cm -2 , the resultant Fe-CQDs/NiMoO 4 /NF revealed an overpotential of only 117 mV for the hydrogen evolution reaction (HER), a relatively low overpotential of 336 mV toward the oxygen evolution reaction (OER), and a Faraday efficiency of up to 99 %. This performance can be attributed to the unique 3D nanosheet array structure, the synergistic effect, and the optimal hydrophilia for gas evolution evolved from the electrode surface., (© 2020 Wiley-VCH GmbH.)