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Ability to focus attentional resources on a task is a necessary component of healthy cognitive regulation, which is necessary for normal emotional and cognitive processes, while avoiding distractions that aren't related to the task at hand. However, anxiety may impair the inhibitory and transfer functions of attention. Therefore, in order to explore the modulation of social anxiety on the effect of emotion on cognitive control, individuals with high social anxiety (HSA) and low social anxiety (LSA) completed the emotional Stroop task with the neutral stimuli presented first, followed by the social threat stimuli. The HSA participants exhibited a slower response to threats than neutral words, whereas there was no emotional effect for the LSA participants. Event-Related Potential (ERP) data revealed that N2 was more negative elicited by neutral words than threat ones in the LSA, but not significant in HSA. Time–Frequency Representation (TFR) data showed enhanced theta synchronization elicited by neutral words than threat words in the LSA only. These findings provided new electrophysiological correlates for social anxiety modulating the effect of emotion on cognitive control. [ABSTRACT FROM AUTHOR]

Artificial enzymes with high stability, adjustable catalytic activity, controllable preparation, and good reproducibility have been widely studied. Noble metal nanozymes, particularly gold nanoparticles (Au NPs), exhibit good catalytic activity, but their stability is poor. In this study, zeolitic imidazolate framework-8 (ZIF-8) was used as a carrier for Au NPs, thus improving the utilization efficiency and conservation stability of the nanozymes. A ZIF-8/Au nanocomposite with peroxidase activity and a raspberry-shaped structure was synthesized. In the assay, ZIF-8/Au catalyzed the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) to a blue product oxidized TMB (oxTMB). Glutathione (GSH) selectively inhibited this reaction, with a detection limit of 0.28 µM and linear range of 0.5–60 µM. Using the photo and chromaticity analysis functions, we developed a portable analysis method using a smartphone equipped with a camera module as a detection terminal for a wide range of rapid screening techniques for GSH. Preparation of raspberry-shaped ZIF-8/Au improved the catalytic activity of Au NPs and good results were demonstrated in serum, which suggests their promising application under physiological conditions. [ABSTRACT FROM AUTHOR]

The precisely modulated synthesis of programmable light‐emitting materials remains a challenge. To address this challenge, we construct four tetraphenylethylene‐based supramolecular architectures (SA, SB, SC, and SD), revealing that they exhibit higher electrochemiluminescence (ECL) intensities and efficiencies than the tetraphenylethylene monomer and can be classified as highly efficient and precisely modulated intramolecular aggregation–induced electrochemiluminescence (PI‐AIECL) systems. The best‐performing system (SD) shows a high ECL cathodic efficiency exceeding that of the benchmark tris(2,2′‐bipyridyl)ruthenium(II) chloride in aqueous solution by nearly six‐fold. The electrochemical characterization of these architectures in an organic solvent provides deeper mechanistic insights, revealing that SD features the lowest electrochemical band gap. Density functional theory calculations indicate that the band gap of the guest ligand in the SD structure is the smallest and most closely matched to that of the host scaffold. Finally, the SD system is used to realize ECL‐based cysteine detection (detection limit=14.4 nM) in real samples. Thus, this study not only provides a precisely modulated supramolecular strategy allowing chromophores to be controllably regulated on a molecular scale, but also inspires the programmable synthesis of high‐performance aggregation‐induced electrochemiluminescence emitters. [ABSTRACT FROM AUTHOR]

The precisely modulated synthesis of programmable light‐emitting materials remains a challenge. To address this challenge, we construct four tetraphenylethylene‐based supramolecular architectures (SA, SB, SC, and SD), revealing that they exhibit higher electrochemiluminescence (ECL) intensities and efficiencies than the tetraphenylethylene monomer and can be classified as highly efficient and precisely modulated intramolecular aggregation–induced electrochemiluminescence (PI‐AIECL) systems. The best‐performing system (SD) shows a high ECL cathodic efficiency exceeding that of the benchmark tris(2,2′‐bipyridyl)ruthenium(II) chloride in aqueous solution by nearly six‐fold. The electrochemical characterization of these architectures in an organic solvent provides deeper mechanistic insights, revealing that SD features the lowest electrochemical band gap. Density functional theory calculations indicate that the band gap of the guest ligand in the SD structure is the smallest and most closely matched to that of the host scaffold. Finally, the SD system is used to realize ECL‐based cysteine detection (detection limit=14.4 nM) in real samples. Thus, this study not only provides a precisely modulated supramolecular strategy allowing chromophores to be controllably regulated on a molecular scale, but also inspires the programmable synthesis of high‐performance aggregation‐induced electrochemiluminescence emitters. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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]

The metal–organic framework (MOF-74) series has the most open metal sites. The metal ions have different bonding strengths with the ligand in MOF-74 and the bond of the ligand can be successively broken to obtain highly active heteroparticles by controlling the temperature, which is difficult to achieve using traditional methods. Magnetic NiCo/Fe3O4-MOF-74, which is fabricated using trimetallic NiCoFe-MOF-74 as a precursor, is simple and rational in comparison with the traditional magnetic core and tunable MOF shell hybrid composites that are formed using a step-by-step assembly strategy. After thermal treatment under a specific atmosphere, NiCo/Fe3O4-MOF-74 shows higher stability, strong magnetism and more active metal sites compared to the original MOF. NiCo/Fe3O4-MOF-74 shows excellent enrichment capability for the removal of tetracycline, with a high removal efficiency that reached 94.1% within 5 min, which is much higher than that of NiCoFe-MOF-74. The main interaction between the adsorbent and analyte is most likely attributed to the open metal sites that can form a stable metal–ligand with the antibiotic molecules. Furthermore, the material can be reused five times without considerable loss. The prepared material has potential applications for removing antibiotics with high efficiency at low cost. Therefore, the experiments described in this study provide a route to a broad class of MOF-based materials for detecting organic contaminants. [ABSTRACT FROM AUTHOR]

Highly efficient detection in the aqueous phase for water‐insoluble organic molecule probes is challenging. The bright aggregated‐state electrochemiluminescence (ECL) of 1,1‐disubstituted 2,3,4,5‐tetraphenylsiloles by a co‐reactant approach was discovered, and a heterogeneous aggregation‐induced emission ECL (HAIE‐ECL) was constructed at the electrode surface, showing very high ECL efficiency (37.8 %) and selective recognition for industrially important DNBP plasticizer with a low detection limit of 0.15 nm in the water phase. A mechanistic study indicates that ECL is mainly generated due to the high electron affinity of siloles and restriction of the intramolecular motions caused by their propeller‐like noncoplanar structures. This system realizes the sensing of organic‐based ECL in the water phase by solving the crucial problems of water insolubility and aggregation‐caused quenching (ACQ), and demonstrates potential for further application because of its design and high efficiency. A heterogeneous aggregation‐induced emission electrochemiluminescence (HAIE‐ECL) system with high ECL efficiency has been developed according to the AIE strategy. This system can detect a widely used plasticizer, DNBP, in the aqueous phase, and solve water insolubility and aggregation‐caused quenching (ACQ) in small organic molecule probe systems. [ABSTRACT FROM AUTHOR]

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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 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. [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]