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The development of efficient catalytic electrode toward oxygen reduction reaction (ORR) is still a great challenge for the wide use of zinc–air batteries. Herein, Co2N nanoparticles (NPs) anchored on N‐doped carbon from cattail were verified with excellent catalytic performances for ORR. The onset and half‐wave potentials over the optimal catalyst reach to 0.96 V and 0.84 V, respectively. Current retention rates of 96.8% after 22‐h test and 98.8% after running 1600 s were obtained in 1 M methanol solution. Density functional theory simulation proposes an apparently increased electronic states of Co2N in N‐doped carbon layer close to the Fermi level. Higher charge density, favorable adsorption, and charge transfer of intermediates originate from the coexistence of Co2N NPs and N atoms in carbon skeleton. The superior catalytic activity of composites also was confirmed in zinc–air batteries. This novel catalytic property and controllable preparation approach of Co2N‐carbon composites provide a promising avenue to fabricate metal‐containing catalytically active carbon from biomass. [ABSTRACT FROM AUTHOR]

An ultrafast, non-invasive and large-scale visualization method has been developed to evaluate the dispersion of two-dimensional nanosheets in aqueous solution with a fluorescence microscope by the formation of excimers from the improvement of cation–π interactions. [ABSTRACT FROM AUTHOR]

Organic solid‐state luminescence materials have shown great promise in many forefront areas of modern chemistry. However, the well‐developed organic luminescent solids usually provoke a mass of synthetic steps. To better utilize their performances, the development of simple strategies for host materials is a goal of general concern. Herein, a series of highly efficient solid‐state luminescence materials are attained with aid of one‐step acidification of commercially available molecules. The mechanism demonstrates that the luminous efficiency of the solid‐state molecules is efficiently improved due to the synergy from the emergence of cation–π interaction and the formation of excimer. The cation–π interaction replaces π–π packing, leading to the formation of dimers with higher rigidity in solid state accompanied by red‐shifted emissions. Therefore, this one‐step acidification design concept will light the great passion of scientists for the fabrication of cation−π‐triggered analogous organic solid‐state luminescence materials with different colors by changing the substituents on benzene moieties. [ABSTRACT FROM AUTHOR]

Luminescence quenching of organic molecules in an aggregation state has become a long-standing challenge for further imaging applications. Inspired by recent research on cation–π interaction triggered luminescence, we designed and synthesized an organic cation, E-4-formyl-styryl-pyridinium salt (FSPH), with strong fluorescent emission in the aggregation state. The formation of the FSPH dimer replaces weaker π–π interactions with stronger cation–π interactions to trigger the aggregation luminescence. The excellent optical performances of FSPH in the aggregation state show promise in elucidating the adsorption kinetics of clays because the aggregation of adsorbates during clay adsorption is inevitable. Expectedly, the complete adsorption kinetics of FSPH on clays was visualized by virtue of an in situ fluorescence imaging technique. The subsequent fluorescence intensity quantification revealed that the adsorption kinetics of FPSH on clays could be divided into three stages: molecular aggregation at the edge, formation of a block layer, and molecular invasion from the edge to the center. The discovery of the formation of a block layer not only identifies a previously unknown source of the lower adsorption capacity with larger particle sizes of clays, but also inspires the great passion of scientists to study the adsorption kinetics of other adsorbents by employing cation–π interaction-triggered aggregation luminescence. [ABSTRACT FROM AUTHOR]

In the present study, monolithic zirconia was prepared using zirconyl oxalate sol as the precursor and urea-formaldehyde resin as the sacrificial template. Under optimal conditions, the as-prepared zirconia monolith demonstrated interconnected skeletons and textural pores (macropores). Nitrogen adsorption–desorption analysis indicated the presence of mesopores in the skeletons of the zirconia monolith. X-ray powder diffraction showed that the synthesized zirconia comprised two types of zirconia phase: monoclinic and tetragonal. [ABSTRACT FROM PUBLISHER]

Background: Coronary to pulmonary artery fistula (CPAF) is rare; reports on the prevalence and types of CPAF in a large cohort of patients are scarce. Purpose: To analyze the prevalence and types of CPAF on computed tomography coronary angiography (CTCA) in a large Chinese population. Material and Methods: CTCA data of 58,533 patients from five Chinese tertiary referral medical centers were retrospectively studied. The prevalence, origin, aneurysmal sac, fistula tracts, and extracardiac communication of CPAF were recorded. CTCA findings were compared with conventional coronary angiography when possible. Results: Ninety-nine patients had CPAF (prevalence of 0.17%). Of the 99 CPAF cases, fistulas were found to originate from either both coronary arteries in 52 patients or from one coronary artery (33 cases from the left and 14 cases from the right coronary artery). Ten CPAF patients were complicated with the communication of extracardiac arteries. Fifteen (15.2%) CPAF patients had aneurysmal sac formation. Thirty (30.3%) patients had a single fistula tract, while 69 (69.7%) patients had multiple fistula tracts. CTCA findings in 16 patients were similar to those at DSA. Conclusion: Based on this large cohort, the prevalence of CPAF in the Chinese population is about 0.17%, with origin from either the left or right coronary artery or from both. CTCA can clearly visualize the types, abnormal vascular tracts, and aneurysmal sac formation of CPAF. [ABSTRACT FROM AUTHOR]

A suspension with good rheology and high stability is crucial for slip casting and gelcasting technology. However, a mixed suspension from two or more different powders usually has bad rheology because of the easy agglomeration of mixed powders caused by the attractive force between the powders with heterocharges. We studied the surface modification of the each single-component powders ( SiC, Al2O3, ZrO2(3 Y) powders) and the SiC- Al2O3- ZrO2(3 Y) mixed powders to increase the repulsive force by adjusting the pH value and adding polyacrylic acid ( PAA) as dispersant. The PAA addition effects on the SiC- Al2O3- ZrO2(3 Y) mixture were investigated in terms of zeta potential, pH range for heterocharge region, dispersion of the mixed powders and rheology of the mixed slurry based on the study of each unary suspensions. The results show that before surface modification the SiC- Al2O3- ZrO2(3 Y) mixed powders were agglomerated severely because they were in the heterocharge region with a broad pH range from 3.5 to 8.25, while after surface modification ( pH = 10.5, PAA = 0.8wt%) the heterocharge region was narrowed with a relatively narrower pH range from 2.6 to 3.7. The mixed powders with homocharges were dispersed well because of the great electrostatic repulsive force and steric hindrance offered by PAA and the mixed suspensions had favorable rheology. [ABSTRACT FROM AUTHOR]

Catalytic performance of Al‐MCM‐41‐supported vanadia catalysts (V/Al‐MCM‐41) with different V loading was investigated for oxidative dehydrogenation of ethylbenzene to styrene (ST) with CO2 (CO2‐ODEB). For comparison, pure silica MCM‐41 was also used as support for vanadia catalyst. The catalysts were characterized by N2 adsorption, X‐ray diffraction (XRD) pyridine‐Fourier‐transform infrared spectroscopy, H2‐temperature‐programmed reduction, thermogravimetric analysis (TGA), UV‐Raman, and diffuse reflectance (DR) UV–vis spectroscopy. The results indicate that the catalytic behavior and the nature of V species depend strongly on the V loading and the support properties. Compared with the MCM‐41‐supported catalyst, the Al‐MCM‐41‐supported vanadia catalyst exhibits much higher catalytic activity and stability along with a high ST selectivity (>98%). The superior catalytic performance of the present V/Al‐MCM‐41 catalyst can be attributed to the Al‐MCM‐41 support being more favorable for the high dispersion of V species and the stabilization of active V5+ species. Together with the characterization results of XRD, TGA, and DR UV–Vis spectroscopy, the deep reduction of V5+ into V3+ during CO2‐ODEB is the main reason for the deactivation of the supported vanadia catalyst, while the coke deposition has a less important impact on the catalyst stability. [ABSTRACT FROM AUTHOR]