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Lithium titanate is a promising anode material for lithium-ion batteries, but its specific capacity and rate performance are low, which restricts its further development. In this paper, by modifying with anchoring carbon particles on the surface, the electrochemical energy storage performance of lithium titanate has been improved at a deeper voltage (0.01–3 V vs. Li+/ Li). The experimental results show that the modified lithium titanate has significant improvement in specific capacity, rate and cycle stability (305.7 mAh g−1 at 0.1 A g−1, 157 mAh g−1 at 5 A g−1, and 245.3 mAh g−1 at 0.1 A g−1 after 800 cycles). Further research found that the improvement of lithium titanate performance is mainly related to a multi-step restore of Ti4+ below 0.6 V, but not to the electrochemical redox of Ti4+/Ti3+ at 1.55 V. This work provided an effective way to promote the comprehensive electrochemical performance of LTO-based materials. Unlabelled Image • Nitrogen-doped carbon nanoparticles • Modified lithium titanate by non-full coverage carbon coating • Effectively improving the rate performance of lithium titanate as Li- battery anode [ABSTRACT FROM AUTHOR]

New-onset atrial fibrillation (AF) is frequently observed following acute stroke. The aim of this study was to investigate the effects of the brain-stellate ganglion-atrium network on AF vulnerability in a canine model with acute middle cerebral artery occlusion (MCAO). Twenty-six dogs were randomly divided into the sham-operated group (n = 6), acute stroke (AS) group (n = 7), stellate ganglion ablation (SGA) group (n = 6) and clodronate liposome (CL) group (n = 7). In the sham-operated group, dogs received craniotomy without MCAO. Cerebral ischemic model was established in AS dogs by right MCAO. Right MCAO along with SGA and CL injection into the atrium was performed in SGA and CL dogs, respectively. After 3 days, atrial electrophysiology, neural activity, and the phenotype and function of macrophages in the atrium were studied in all the dogs. Higher AF inducibility (24.4 ± 4.4% versus 4.4 ± 2.2%, P < 0.05) and AF duration (15.7 ± 3.8 s versus 2.6 ± 1.1 s, P < 0.05) were observed in the AS group compared with the sham-operated group, and were associated with increased left stellate ganglion activity, higher macrophage infiltration and higher levels of inflammatory cytokines in the atrium. SGA or CL injection sharply suppressed AF inducibility (5.5 ± 2.7% versus 24.4 ± 4.4%; 5.3 ± 3.2% versus 24.4 ± 4.4%, both P < 0.05) and AF duration (2.9 ± 1.2 s versus 15.7 ± 3.8 s; 3.6 ± 1.0 s versus 15.7 ± 3.8 s, both P < 0.05) in canines with acute stroke. A brain-stellate ganglion-atrium network may increase AF vulnerability through macrophage activation after acute stroke. [ABSTRACT FROM AUTHOR]

Carbon-based anode materials with unique structure, high electrical conductivity, high Li storage performance and excellent cycling stability are promising alternatives to traditional graphite anode materials in lithium-ion batteries (LIBs). Here we report a flower-like carbon material with hierarchical structure that is prepared by carbonization of a flower-like Zn-based metal-organic framework (MOF). The 2D layered MOF network precursor, namely [Zn(BDC)(MelM)·(DMF)] (BDC = benzene dicarboxylic acid, MelM = 2-Methylimidazole), is constructed using two ligands under solvothermal conditions. As an anode material for LIBs, these carbon nanoflakes exhibit remarkable electrochemical performance (capacity, cyclability, and rate capability); the capacity of 902.5 mAh g−1 was retained after 200 cycles at a current density of 100 mA g−1. The remarkable performance results from the unique morphology of carbon nanoflakes which is beneficial for infiltration of electrolyte and the transportation of Li ions. Image 1 • Preparation of 2D layered metal-organic framework. • Interesting 2D nanostructures of flower-like carbon material. • The kind of anode material for LIBs possess excellent electrochemical performance. [ABSTRACT FROM AUTHOR]

• Shear connectors can be omitted in the PECB. • The PECB under flexure can behave satisfactorily. • Practical models are derived and validated for the PECB. This paper focuses on a new type of composite beam designated as the partially encased cellular beam (PECB). The PECB consists of a steel wide-flange member in which its perforated web is encased by reinforced concrete. The PECB is envisioned to be superior to the conventional partially encased beam in that it can eliminate the need of shear connectors required in the conventional partially encased beam to develop the desired composite action. This feature helps alleviate reinforcement congestion that may exists in a conventional partially encased beam and minimize construction cost and effort. To investigate the flexural behavior of the proposed PECB, five specimens with representative geometries and typical materials were designed and constructed. The specimens were monotonically loaded with the four-point bending test setup. Test results show that the proposed PECB can behave satisfactorily under flexure and that the shear connectors may not be needed in a properly designed PECB for development of the composite action. Based on the classic beam theory and idealized stress/strain diagrams, this paper develops three practical models for estimating the yield flexural strength, plastic flexural strength, and initial flexural stiffness of the proposed PECB. Comparisons of the predictions from these models with the test results show that the practical models can provide reasonable predictions and can be used for future practice. [ABSTRACT FROM AUTHOR]

Highlights: [•] Disappearance kinetics of pyridaben in cabbage under field condition was studied. [•] Pyridaben residue analysis was carried out by a validated and accredited method. [•] Risk assessment of pyridaben in cabbage was evaluated. [ABSTRACT FROM AUTHOR]

A series of KNiF 3 @carbon nanotubes (CNTs) are synthesized via a facile solvothermal method and applied as supercapacitor electrodes. The addition of carbon nanotubes can significantly overcome the rate capability defect of bare KNiF 3 and improve the specific capacity to a certain extent, which mainly owing to the increase of conductivity and electron/ion transports capacity. In addition, the cross-linked structure of carbon nanotubes and the evenly anchoring of KNiF 3 nanoparticles can increase the stability of the composites. As a result, the optimal candidate KNiF 3 @CNTs-8 (the content of carbon nanotubes is 8 mg and the mass fraction is 1.0%) shows highest specific capacity (821.4 C g−1 at 1 A g−1) and capacity retention (83.6% at 16 A g−1). The asymmetric supercapacitor AC//KNiF 3 @CNTs-8 delivers extremely high energy density of 63.7 Wh kg−1. More importantly, the ASC device shows ultra-long cycling stability, with 95.9% capacity retention after 5000 cycles. These results prove that KNiF 3 @CNTs can be a promising material for supercapacitor. Image 1 • KNiF 3 @CNTs-8 presented high specific capacity and excellent rate capability. • The optimal composite material exhibited high electrical conductivity. • An asymmetric supercapacitor AC//KNiF 3 @CNTs-8 was fabricated and investigated. • The ASC device exhibited ultra-high energy density and excellent cycling life. [ABSTRACT FROM AUTHOR]