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Sodium-ion and potassium-ion batteries (NIBs and KIBs) are considered promising alternatives to replace lithium-ion batteries (LIBs) in energy storage applications due to the natural abundance and low cost of Na and K. Nevertheless, a critical challenge is that the large size Na+/K+ leads to a huge volume change of the hosting material during electrochemical cycling, resulting in rapid capacity decay. Among negative candidates for alkali-metal-ion batteries, SnS2 is attractive due to the competitively high specific capacity, low redox potential and element's abundance. Porous few-layer SnS2 nanosheets are in situ grown on reduced graphene oxide, forming a SnS2-rGO sandwich structure via strong C-O-Sn bonds. This nano-scaled sandwich structure not only shortens Na+/K+ and electron transport pathways but also accommodates volume expansion, thereby enabling high and stable electrochemical cycling performance of SnS2-rGO. This work explores the influence of different conductive carbons (Super P and C65) on the SnS2-rGO electrode. In addition, the effects of the electrolyte additive fluoroethylene carbonate (FEC) on the electrochemical performance in NIBs and KIBs is evaluated. This work provides guidelines for optimized electrode structure design, electrolyte additives and carbon additives for the realization of better NIBs and KIBs.

Doped Tin (IV) Oxide has excellent potential in high-temperature thermoelectrics because of its large bandgap. It has been thoroughly experimentally studied for high-temperature thermoelectric application. Low electron mobility limits the thermoelectric performance of oxides. Understanding the temperature dependence of mobility help increase thermoelectric performance. This is rarely performed. In this work, we study antimony doped tin dioxide. Combining the calculated transport properties and the existing experimental results, we obtain other transport properties. Unlike in bulk materials, the grain boundary scattering competes against the acoustic phonon scattering. The grain size, temperature, and carrier concentration determine the mobility. The small grain, low carrier concentration, and high temperature are beneficial to the mobility. Antimony doping also causes the Fermi level into the conduction band as deep as 0.59 eV, making the large bandgap SnO2 metallic. Furthermore, the conductivity effective mass demonstrates the doping effect. These findings might help design new oxide thermoelectric materials by decrease the grain size.

This work is focused on the mechanism study of nanoscale Co3O4 powders prepared by an enhanced solid-state reaction method. The as-prepared powders are characterized by thermogravimetric-differential scanning calorimetry (TG-DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) with the powders ball milled for different times as the control. The results show that ball milling can accelerate the thermal decomposition process by approximately 18.2%. Moreover, the apparent thermal decomposition activation energy of CoCO3 powders pretreated by the enhanced solid-state method declined by 33.2%. To elucidate this,the thermal decomposition kinetic equations of CoCO3 powders, with and without ball milling, are calculated. And the thermal decomposition kinetic equation of the ball-milled powders is dα/dt = (2.42E6~2.19E7) exp [(8.74E3~9.96E3)/T] 4/3(1-α) [-ln(1-α)]1/4; while that of the powders lack of ball milling is dα/dt = (1.08E10–1.07E11) exp [(1.43E4~1.51E4)/T] 2/3α−1/2, respectively. The reaction process at different time points can be forecasted by the obtained equations.

Sampling is a basic operation of modern convolutional neural networks (CNN) since down-sampling operators are employed to enlarge the receptive field while up-sampling operators are adopted to increase resolution. Most existing deep segmentation networks employ regular grid sampling operators, which can be suboptimal for semantic segmentation task due to large shape and scale variance. To address this problem, this paper proposes a Context Guided Dynamic Sampling (CGDS) module to obtain an effective representation with rich shape and scale information by adaptively sampling useful segmentation information in spatial space. Moreover, we utilize the multi-scale contextual representations to guide the sampling process. Therefore, our CGDS can adaptively capture shape and scale information according to not only the input feature map but also the multi-scale semantic context. CGDS provides a plug-and-play module which can be easily incorporated in deep segmentation networks. We incorporate our proposed CGDS module into Dynamic Sampling Network (DSNet) and perform extensive experiments on segmentation datasets. Experimental results show that our CGDS significantly improves semantic segmentation performance and achieves state-of-the-art performance on PASCAL VOC 2012 and ADE20K datasets. Our model achieves 85.2% mIOU on PASCAL VOC 2012 test set without MS COCO dataset pre-trained and 46.4% on ADE20K validation set. The codes will become publicly available after publication.

Lithium–sulfur batteries (LSBs) show excellent performance in terms of specific capacity and energy density. However, the cyclic stability of LSBs is compromised due to the “shuttle effect”, which hinders the practical applications of LSBs. Herein, a metal–organic framework (MOF) based on Cr ions as the main body composition, commonly known as MIL-101(Cr), was utilized to minimize the shuttle effect and improve the cyclic performance of LSBs. To obtain MOFs with a certain adsorption capacity for lithium polysulfide and a certain catalytic capacity, we propose an effective strategy of incorporating sulfur-loving metal ions (Mn) into the skeleton to enhance the reaction kinetics at the electrode. Based on the oxidation doping method, Mn2+ was uniformly dispersed in MIL-101(Cr) to produce bimetallic Cr2O3/MnOx as a novel sulfur-carrying cathode material. Then, a sulfur injection process was carried out by melt diffusion to obtain the sulfur-containing Cr2O3/MnOx-S electrode. Moreover, an LSB assembled with Cr2O3/MnOx-S showed improved first-cycle discharge (1285 mAh·g−1 at 0.1 C) and cyclic performance (721 mAh·g−1 at 0.1 C after 100 cycles), and the overall performance was much better than that of monometallic MIL-101(Cr) as a sulfur carrier. These results revealed that the physical immobilization method of MIL-101(Cr) positively affected the adsorption of polysulfides, while the bimetallic composite Cr2O3/MnOx formed by the doping of sulfur-loving Mn2+ into the porous MOF produced a good catalytic effect during LSB charging. This research provides a novel approach for preparing efficient sulfur-containing materials for LSBs.

Stabilization/Solidification (S/S) is considered as a feasible technology for the treatment of arsenic (As) in acidic wastewater (AW) and tin mine tailings (TMTs); however, high cost, high carbon footprint, and strict reaction conditions are the main limitations. Herein, a novel alkali-activated geopolymer material (AAGM) for S/S As was synthesized by combining AW, TMT, gypsum (GP), and metakaolin (MK). At room temperature, an initial As concentration of 3914 mg/L, a NaOH content of 4.98%, and an MK content of 20% decreased the As leaching concentration to 1.55 mg/L (5 mg/L). The main S/S mechanisms of As included physical encapsulation of C-(A)-S-H and geopolymer structures, ion exchange of ettringite, and formation of Fe-As and Ca-As precipitates. Further studies showed that increasing initial As concentration and MK content facilitated the formation of Ca-As precipitates and C-(A)-S-H gels. The semi-dynamic leaching tests revealed that the leaching mechanism of As was surface wash-off. The effective diffusion coefficients of the samples were less than 10

Enhanced thermal decomposition of carbonates is developed to improve the traditional solid state reaction for the synthesis of ultrafine LiNi1/3Co1/3Mn1/3O2 powders. Controllable activation is obtained by optimizing the mechano-chemical treatment time, which is found to affect lattice structure, morphology and electrochemical properties of the as-synthesized ultrafine LiNi1/3Co1/3Mn1/3O2 powders. The optimal mechano-chemical activation time of 10 h results in more stable and integrated structured ultrafine LiNi1/3Co1/3Mn1/3O2 powders with average diameter of 200–500 nm, leading to a high reversible capacity of 114.3 and 140.9 mAh g−1 at 6 C (1620 mA g−1) in the voltage range of 2.5–4.3 and 2.5–4.5 V, respectively. Moreover, the particles exhibit capacity retentions of 80.8% (2.5–4.3 V) and 83.3% (2.5–4.5 V) at 270 mA g−1 after 200 cycles. Importantly, it is revealed that ball-milling has a positive impact on the calcination process, and the decomposition efficiency is about 35.7% higher compared to ball-milling-free process. The LiNi1/3Co1/3Mn1/3O2 powders prepared by enhancing thermal decomposition show a remarkable high temperature electrochemical property. For optimum performance, the time of mechano-chemical activation should be neither too long nor too short. In addition, the calcination process is further studied in order to understand the transformation regularities of the electrode materials.

The treatment of arsenic (As) in tin tailings (TT) has been an urgent environmental problem, and stabilization/solidification (S/S) treatment is considered an effective technology to eliminate contamination of As. In this study, we developed a low-carbon and low-alkalinity material to S/S of As, and the results showed that the leaching concentration of As after treatment was lower than the Chinese soil environmental quality standard (0.1 mg/L). Based on a series of characterization tests, we found that OH− promoted the dissolution of As(III)-S, Fe-As(V), and amorphous As(III)-O species and formed Ca-As(III) and Ca-(V) species with Ca2+. Simultaneously, hydration produces calcium silicate hydrate (C-S-H) gel and ettringite by the form of adsorption and ion exchange to achieve S/S of As. We also assessed the durability of this material to acidity and temperature, and showed that the leaching concentration of As was below 0.1 mg/L at pH = 1–5 and temperature 20–60 °C. The method proposed in this study, S/S of As, has excellent effect and environmental durability, providing a new solution for harmless treatment of TT and its practical application.

A critical event in cardiac fibrosis is the transformation of cardiac fibroblasts (CFs) into myofibroblasts. MicroRNAs (miRNAs) have been reported to be critical regulators in the development of cardiac fibrosis. However, the underlying molecular mechanisms of action of miRNA (miR)-26b in cardiac fibrosis have not yet been extensively studied. In the present study, the expression levels of miR-26b were downregulated in isoproterenol (ISO)-treated cardiac tissues and CFs. Moreover, miR-26b overexpression inhibited the cell viability of ISO-treated CFs and decreased the protein levels of collagen I and α-smooth muscle actin (α-SMA). Furthermore, bioinformatics analysis and dual luciferase reporter assays indicated that Kelch-like ECH-associated protein 1 (Keap1) was the target of miR-26b, and that its expression levels were decreased in miR-26b-treated cells. In addition, Keap1 overexpression reversed the inhibitory effects of miR-26b on ISO-induced cardiac fibrosis, as demonstrated by cell viability, and the upregulation of collagen I and α-SMA expression levels. Furthermore, inhibition of Keap1 expression led to the activation of nuclear factor erythroid 2-related factor 2 (Nrf2), which induced the transcriptional activation of antioxidant/detoxifying proteins in order to protect against cardiac fibrosis. Taken together, the data demonstrated that miR-26b attenuated ISO-induced cardiac fibrosis via the Keap-mediated activation of Nrf2.

For the aluminium doped wurtzite ZnO, comparing the Boltzmann transport theory calculated results and existing experiments, we acquire a few properties that are inaccessible otherwise. We find that the doping makes the samples metallic as the shifted Fermi levels are above the conduction band edge. We further find that the contradictory conclusions from two experiments with similar formula can be attributed to the quite disparate carrier concentrations and carrier mobility and the carrier mobility strong relates to the sample preparation.

TiC-reinforced AZ91D magnesium alloy composites were synthesized through the in situ reaction between an AZ91D melt and Ti-C-Al preforms. The microstructural evolution characteristics and phase transformation were investigated at different melt reaction temperatures (1013, 1033, and 1053 K), with the aim of understanding the in situ formation mechanism of TiC particles from thermodynamic and kinetic perspectives. The results showed that the temperature played a critical role in determining the formation and morphology of TiC. Initially, only the Al3Ti phase was formed through the reaction between Ti and Al when the temperature was 1013 K. With the increase in the melt temperature, the A13Ti’s thermodynamic stability decreased, and dissolution and precipitation reactions occurred at higher temperatures (1033 and 1053 K, respectively), contributing to the formation of TiC particles. The formation of the TiC phase was attributed to two factors: Firstly, A13Ti as an intermediate product reacted with carbon and formed TiC with increasing temperature. Secondly, the in situ TiC reaction was promoted due to the increased reaction-driving force provided by the increasing temperature.

Balancing hydrogen (Hads) and hydroxyl (OHads) adsorption/desorption plays a pivotal role to accelerate the sluggish alkaline hydrogen evolution reaction (HER) kinetics. Unfortunately, the adsorption energies for Hads and OHads can hardly be optimized simultaneously due to the lack of matched active sites for Hads and OHads. Herein, cation and anion codoping is used to construct Co and B doped Ni3S4 (Co-B-Ni3S4) with dual active sites to synergistically near-optimal adsorption energies for Hads and OHads concurrently. The obtained catalyst exhibits a superior HER performance with a tiny overpotential of 35 mV to obtain current density 10 mA cm−2 and a low Tafel slope of 52 mV dec-1, even outperforms Pt/C at high current density. The related microkinetics analysis and density functional theory confirm that the B doping can elevate d-band center to facilitates the water dissociation, Co doping endows the appropriate Had adsorption energies to accelerate generation and release for H2. This work points out a venue for kinetic-oriented design of alkaline HER and beyond at the atomic level.

Ultrafine LiCoO 2 powders were directly synthesized by enhancing thermal decomposition of Cobalt and Lithium carbonates through a mechanochemical activation treatment to intensify the solid state diffusion reaction. Effects of activation treatment time on particle size and structure of the LiCoO 2 compound were investigated. In the present study, the optimum mechano-chemical activation time was found to be 10 h. In this study, the ultrafine LiCoO 2 powders (particle size in the range from 200 nm to 400 nm) show good structural stability and higher structural integrity. X-ray photoelectron spectroscopy (XPS) results indicate that most of Co cations exist as Co 3+ , which contributes to the improvement of the electrochemical performance. Cyclic voltammetry (CV) curves of different cycles display almost a complete overlap, which can be regarded as another evidence of the excellent cycle performance. The LiCoO 2 powders exhibit a high initial discharge specific capacity of 175.2 mAh/g at 0.1 C (274 mA/g at 1 C) and a remarkable cycle stability from 167.5 mAh/g to 146.2 mAh/g at 0.5 C and from 147.5 mAh/g to 115.2 mAh/g at 3 C after 100 cycles in the range of 3.3–4.3 V. The apparent activation energy and the frequency factor of the decomposition of CoCO 3 are 69.83 kJ/mol and 1.369×10 6 , respectively, indicating that the ultrafine in-process product of Co 3 O 4 can be quickly prepared at a low temperature.

The composite of porous carbon obtained from MOFs loading sulfur has been regard as promising candidate for lithium-sulfur batteries cathode material due to the large specific surface area, high porosity, diversity of types, and designable structures large specific surface area, high porosity, diversity of types, and designable structures. However, the production processes of MOFs materials play a pivotal role on the lithium-sulfur batteries performance. Herein, the effect of key process parameters such as heat treatment temperature, heat treatment time, and heat treatment atmosphere on the electrochemical performance of lithium-sulfur batteries were systematically studied. The results show that at a heating rate of 5 ℃·min−1, heat preservation at 900 ℃ for 3 h, and treatment with CO2 airflow for 1 h, the composite material has the best electrochemical performance. The first discharge specific capacity of the lithium-sulfur battery reached 1060.32 mAh·g−1, and after 50 cycles it reached 614.29 mAh·g−1. This heat treatment research method based on MOFs-derived materials can be used as a reference for related research in other energy storage and conversion fields.

A critical event in cardiac fibrosis is the transformation of cardiac fibroblasts (CFs) into myofibroblasts. MicroRNAs (miRNAs) have been reported to be critical regulators in the development of cardiac fibrosis. However, the underlying molecular mechanisms of action of miRNA (miR)-26b in cardiac fibrosis have not yet been extensively studied. In the present study, the expression levels of miR-26b were downregulated in isoproterenol (ISO)-treated cardiac tissues and CFs. Moreover, miR-26b overexpression inhibited the cell viability of ISO-treated CFs and decreased the protein levels of collagen I and α-smooth muscle actin (α-SMA). Furthermore, bioinformatics analysis and dual luciferase reporter assays indicated that Kelch-like ECH-associated protein 1 (Keap1) was the target of miR-26b, and that its expression levels were decreased in miR-26b-treated cells. In addition, Keap1 overexpression reversed the inhibitory effects of miR-26b on ISO-induced cardiac fibrosis, as demonstrated by cell viability, and the upregulation of collagen I and α-SMA expression levels. Furthermore, inhibition of Keap1 expression led to the activation of nuclear factor erythroid 2-related factor 2 (Nrf2), which induced the transcriptional activation of antioxidant/detoxifying proteins in order to protect against cardiac fibrosis. Taken together, the data demonstrated that miR-26b attenuated ISO-induced cardiac fibrosis via the Keap-mediated activation of Nrf2.

First, we solve a semi-classical electronic Boltzmann transport equation and acquire the thermoelectric coefficients for a pure unit cell using the rigid-band approximation. Then, combined with the existing experimental results, we not only reproduce the Seebeck coefficients and electrical conductivity but also yield the carrier concentrations and relaxation time, which cannot be obtained by either experiments or theories alone. Our results are in good agreement with the experiment for all doping samples. Furthermore, we show that Wiedemann-Franz law fails to connect the electronic thermal conductivity with the electrical conductivity. We also show that the Hall effect fails to measure carrier concentration in this study. We attribute these failures to the breakdown of the parabolic band. We think that our approach can be extended to other alloy or compound thermoelectric materials that utilize electronic transport property because they all have problems identifying relaxation time and carrier concentrations.

In this paper, ZrO2-coated LiNi1/3Mn1/3Co1/3O2 is successfully prepared by the microwave pyrolysis method. The structure and electrochemical properties of the ZrO2-coated LiNi1/3Co1/3Mn1/3O2 are investigated using x-ray diffraction, AC impedance, and charge/discharge tests, indicating that the lattice structure of LiNi1/3Co1/3Mn1/3O2 is unchanged after the coating but the cycling stability is improved. As the coating amount is 2 wt.%, initial capacity of the coated LiNi1/3Co1/3Mn1/3O2 decreases slightly. However, the cycling stability increases remarkably over the cut-off voltages of 2.75~4.3 V and the capacity retention reaches 93.1% after 50 cycles. Electrochemical impedance spectra results show that the increase of charge transfer resistance during cycling is suppressed significantly by coating with ZrO2.

Au@Pt core-shell nanoparticles were synthesized by a simple one-step ultraviolet irradiation method and were then assembled on functionalized multiwalled carbon nanotubes (MWCNTs) surface. This new type of Au@Pt/MWCNTs composite catalysts was characterized by UV–vis spectrometry, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning TEM, HRTEM, and electrochemical techniques. The results revealed that the Au@Pt nanoparticles with an average diameter less than 5 nm were well coated on the MWCNTs surface. As compared with commercial Pt/C catalysts, the Au@Pt/MWCNTs prepared using Au/Pt atomic ratio of 1:1 exhibited distinctly higher activity and better stability toward methanol oxidation in alkaline media.

Magnesium tetraphenylporphyrin (MgTPP) was synthesized from meso-tetraphenylporphyrin (H(2)TPP) in N,N-dimethylformamide (DMF). The photochemical properties of MgTPP in the presence of oxygen were investigated in dichloromethane (CH(2)Cl(2)) by conventional fluorescence, UV-vis, (1)H NMR, MALDI-TOF-MS, FTIR, and XPS spectroscopic techniques. Spectral analyses showed that under irradiation, MgTPP molecules reacted with O(2) molecules, and a stable 1:1 adduct was produced. During the photochemical reaction process, one oxygen molecule was bound to the pyrrolenine nitrogens in the MgTPP molecule, and the characteristic N-O bonds were identified using the FTIR and XPS techniques. The kinetics of the photochemical reaction of MgTPP with O(2) has been studied in an oxygen-saturated solution. Under irradiation conditions, the experimental rate follows a pseudo-first-order reaction for MgTPP, having a half-life from 40 to 130 min under various irradiation intensities. The kinetic rate constant of photochemical reaction of MgTPP with O(2) showed a linear dependence.

Objective: To compare the effects of embolic agents with different particle sizes on interventional treatment of uterine fibroids (UFs). Methods: One-hundred and thirty patients with UFs were divided into a treatment group and a control group (n=65) by random draw. All patients were treated by uterine artery embolization, with the treatment group using 200 μm polyvinyl alcohol (PVA) particles and the control group using 500 μm PVA particles. Results: The success rate of embolization was 100%. After intervention, the treatment group was significantly less prone to complications such as lower abdominal pain, fever, nausea, vomiting and bleeding than the control group (P

A novel method for synthesizing Au@Pd core-shell nanoparticles was proposed based on photochemistry. By irradiating the mixture of Au (III) and Pd (II) ions using ultraviolet light, the Au@Pd core-shell nanoparticles were prepared. The size of the nanoparticles and the thickness of the Pd shell could be efficiently adjusted by changing the molar ratio of Au (III) to Pd (II) ion. In this way, nanoparticles with diameter in the range of 5.6~4.6 nm were obtained. The core-shell structure of the synthesized nanoparticles was showed by the characterization using UV-Vis, TEM/HR-TEM and XPS. The paper investigated the electrocatalysis performance of Au@Pd nanoparticles in the methanol catalytic oxidation reaction, as well as the electron donating effect of Au core to Pd shell and the promotion of this effect on the catalytic activity of Pd shell. The experimental results provided reference for the development of non-platinum catalysts of low-temperature fuel cell anode.