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Flexible power supply devices provide possibilities for wearable electronics in the Internet of Things. However, unsatisfying capacity or lifetime of typical batteries or capacitors seriously limit their practical applications. Different from conventional heat-to-electricity generators, zinc ion thermoelectrochemical cells has been a competitive candidate for the self-power supply solution, but the lack of promising cathode materials has restricted the achievement of promising performances. Herein, we propose an attractive cathode material by rational heterostructure engineering of hydrated vanadium pentoxide. Owing to the integration of thermodiffusion and thermoextraction effects, the thermopower is significantly improved from 9.1 mV K− 1 to 25.3 mV K− 1. Moreover, an impressive normalized power density of 2.7 mW m− 2 K− 2 is achieved in the quasi-solid-state cells. In addition, a wearable power supply constructed by three units can drive the commercial health monitoring system by harvesting body heat. This work demonstrates the effectiveness of electrodes design for wearable thermoelectric applications.

This study demonstrates the promising potential of cathode microstructural engineering for high value-added energy conversion and storage.

With the associated advantages of low costs and abundant resources, sodium-ion capacitors (SICs) present a suitable means for large-scale energy storage. However, their practical application is still significantly limited by the sluggish electrochemical reaction kinetics of battery-type anodes. Herein, the nitrogen-doped carbon-encapsulated Fe

Lithium-ion capacitors (LICs) are gradually emerging as one of the most indispensable hybrid energy storage devices. However, it is one main challenge to evade the mismatch of electrochemical kinetics and specific capacity between cathode and anode in LICs. Herein, we have proposed an efficient strategy to prepare the nitrogen-doped hierarchical porous carbon spheres (NHPCS) as cathode, which is synthesized by a simple aerosol-spraying pyrolysis using the low-cost phenolic resin as carbon source without any other catalyst or hard template. The NHPCS exhibits porous nanospheres structure with an appropriate nitrogen doping level (3.65 at.%). Benefitting from the two-pronged strategy of N-doped feature and nanostructure engineering, NHPCS achieves a high specific capacity of 74 mAh g−1 at a current density of 0.1 A g−1 and remains 86.5% of initial capacity even being subjected to a high rate of 50-fold. Furthermore, a high-performance LIC has been developed by coupling NHPCS cathode and hard carbon anode, which delivers a maximum energy density of 151 Wh kg−1 and excellent cycle stability (96.3% capacity retention after 3000 cycles). Significantly, such designed porous carbon could not only be convenient for scalable production, but also be served for many other energy storage devices. We have presented a larger-scale spray pyrolysis strategy to prepare nitrogen-doped hierarchical porous carbon spheres (NHPCS). A high-stable lithium-ion capacitor has been constructed by coupling NHPCS cathode with hard carbon anode, which exhibits a maximum energy density of 151 Wh kg−1 and capacity retention of 96.3% over 3000 cycles, showing great potential for the next-generation energy storage application.

Lithium-ion capacitors (LICs) are regarded as the most potential devices in the energy storage systems. Unfortunately, the mismatched in the intrinsic kinetics and specific capacities between anode and cathode lead to a depressed electrochemical performance. Thus, designing an advanced electrode material that combines high performance with low-cost is one of the main challenges for LICs, especially in a sustainable anode material until now. Here, a high-energy LIC has been successfully developed using the defect-rich and N-doped hard carbon (DNC) as anode, which is prepared through the carbonization process of the low-cost biowaste sepia without additional template or catalyst. The DNC shows nanospherical structure with a diameter of about 100 nm. Owing to the two-pronged strategy of N-doping and defect engineering, it delivers a high specific capacity (580.3 mAh g−1 at 0.05 A g−1), excellent rate capability, and long cycle stability (1000 cycles). The electrochemical kinetic analysis and density functional theory (DFT) calculations have confirmed its prominent pseudocapacitive behaviors and excellent Li+ storage capability. As expected, the as-fabricated LIC delivers a remarkable energy density (101.7 Wh kg−1), an outstanding rate capability (56.3 Wh kg−1 at 12.5 kW kg−1), and a superior cycle lifespan (3000 cycles), demonstrating the tremendous potential for the next-generation energy storage systems.

Common oat (Avena sativa) is an important cereal crop serving as a valuable source of forage and human food. Although reference genomes of many important crops have been generated, such work in oat has lagged behind, primarily owing to its large, repeat-rich polyploid genome. Here, using Oxford Nanopore ultralong sequencing and Hi-C technologies, we have generated a reference-quality genome assembly of hulless common oat, comprising 21 pseudomolecules with a total length of 10.76 Gb and contig N50 of 75.27 Mb. We also produced genome assemblies for diploid and tetraploid Avena ancestors, which enabled the identification of oat subgenomes and provided insights into oat chromosomal evolution. The origin of hexaploid oat is inferred from whole-genome sequencing, chloroplast genomes and transcriptome assemblies of different Avena species. These findings and the high-quality reference genomes presented here will facilitate the full use of crop genetic resources to accelerate oat improvement.

Objective: We conducted an updated coordinate-based meta-analysis (CBMA) to determine the most prominent and robust white matter (WM) abnormalities in ADHD based on tract-based spatial statistics (TBSS) findings. Method: The seed-based d mapping (SDM) software was applied to compare regional fractional anisotropy (FA) alterations in ADHD. Subgroup meta-analyses in the pure ADHD without comorbidity subgroup, the children and adolescents subgroup, and the adults subgroup were also explored, respectively. Meta-regression analysis was subsequently used to examine potential correlations between demographics and FA changes. Results: Only one cluster in the splenium of corpus callosum (CC) exhibited age-related FA decrease in ADHD individuals in the pooled meta-analysis. The adults ADHD subgroup revealed two clusters with reduced FA lied in the splenium and body of CC. Conclusion: This updated CBMA confirmed the WM abnormalities in the splenium of CC in ADHD, and improved our understanding of the pathogenesis of this neurodevelopmental disorder.

In this article, two classes of finite difference methods are constructed to solve the space fractional semilinear delay reaction–diffusion equations. Firstly, fractional centered finite difference method in space and backward differential formula (BDF2) in time are employed to discrete the original equations. Secondly, the existence, uniqueness and convergence of the numerical method are analyzed at length by G-norm technique, and the convergence order is O ( τ 2 + h 2 ) . Then the compact technique of finite difference method is used to further increase the accuracy in spatial direction, and a method with fourth accuracy in spatial dimension is obtained. The convergence orders are proved to be O ( τ 2 + h 4 ) in the sense of three classes of norms by GA-norm technique. Especially, we obtain the uniform convergence for the error estimation, which demonstrates competitive performance compared with the preceding work in the related references. Finally, two numerical examples are provided to verify our theoretical results and demonstrate the effectiveness of both methods when applied to simulate space fractional delay diffusive Nicholson’s blowflies equation.

Converting low-grade heat from environment into electricity shows great sustainability for mitigating the energy crisis and adjusting energy configuration. However, the thermally rechargeable devices suffer from poor Seebeck coefficient when a semiconductor or ionic electrolyte is typically employed. Breaking the convention of thermoelectric systems, we propose and demonstrate a new zinc ion thermogalvanic cell to generate electricity from low-grade heat via the thermo-extraction/insertion and thermodiffusion process of insertion-type cathode (VO2-PC) and stripping/plating behavior of Zn anode. Based on this strategy, a high thermopower of ~ 15 mV k− 1 and an excellent output power of 1.2 mW can be impressively obtained. Besides, a high specific capacity and a superior durability are originated from coupling of VO2-PC and Zn. This work with extraordinary energy conversion efficiency and satisfying energy storage capability will pave the way toward construction of thermoelectric setups with attractive property for high value-added utilization of low-grade heat.

Common oat (Avena sativa) is one of the most important cereal crops serving as a valuable source of forage and human food. While reference genomes of many important crops have been generated, such work in oat has lagged behind, primarily owing to its large, repeat-rich, polyploid genome. By using Oxford Nanopore ultralong sequencing and Hi-C technologies, we have generated the first reference-quality genome assembly of hulless common oat with a contig N50 of 93 Mb. We also assembled the genomes of diploid and tetraploid Avena ancestors, which enabled us to identify oat subgenome, large-scale structural rearrangements, and preferential gene loss in the C subgenome after hexaploidization. Phylogenomic analyses of cereal crops indicated that the oat lineage descended before wheat, offering oat as a unique window into the early evolution of polyploid plants. The origin and evolution of hexaploid oat is deduced from whole-genome sequencing, plastid genome and transcriptomes assemblies of numerous Avena species. The high-quality reference genomes of Avena species with different ploidies and the studies of their polyploidization history will facilitate the full use of crop gene resources and provide a reference for the molecular mechanisms underlying the polyploidization of higher plants, helping us to overcome food security challenges.

Aqueous zinc ion hybrid supercapacitors (ZHSCs) have emerged and are regarded as promising candidates for energy storage due to their environmental friendlessness and cost‐effectiveness. However, the development of a satisfying positive electrode with high performance still poses challenges. Herein, a hierarchical porous carbon with a fast‐ion‐transport feature is rationally reported via a facile template modification strategy. By adjusting the content of the template, the physiochemical characteristics and microstructures of carbon can be reasonably optimized. As proof of concept, the produced carbon electrode can deliver a high specific capacitance of 294.8 F g−1 at a current density of 0.2 A g−1, long cycling stability with ≈100% capacitance retention over 20 000 cycles, and a maximum power density of 13.2 kW kg−1 at 30.8 W h kg−1. Significantly, a superior areal capacitance of 3390 mF cm−2 is offered with a mass loading of 21 mg cm−2. When coupled with a unique antifreezing hydrogel electrolyte, the constructed quasi‐solid‐state ZHSC can not only endure −15 °C, but also exhibits outstanding durability and an ultralow self‐discharging rate, demonstrating its potential prospect for extreme conditions. This work may bring light on the preparation of carbon materials and the fabrication of multifunctional devices.

In this paper, one class of finite difference scheme is proposed to solve nonlinear space fractional Sobolev equation based on the Crank-Nicolson (CN) method. Firstly, a fractional centered finite difference method in space and the CN method in time are utilized to discretize the original equation. Next, the existence, uniqueness, stability, and convergence of the numerical method are analyzed at length, and the convergence orders are proved to be O τ 2 + h 2 in the sense of l 2 -norm, H α / 2 -norm, and l ∞ -norm. Finally, the extensive numerical examples are carried out to verify our theoretical results and show the effectiveness of our algorithm in simulating spatial fractional Sobolev equation.

In this paper, we investigate a linearized finite difference scheme for the variable coefficient semi-linear fractional convection-diffusion wave equation with delay. Based on reversible recovery technique, the original problems are transformed into an equivalent variable coefficient semi-linear fractional delay reaction-diffusion equation. Then, the temporal Caputo derivative is discreted by using $L_{1}$ approximation and the second-order spatial derivative is approximated by the centered finite difference scheme. The numerical solution can be obtained by an inverse exponential recovery method. By introducing a new weighted norm and applying discrete Gronwall inequality, the solvability, unconditionally stability, and convergence in the sense of $L_{2}$ - and $L_{\infty }$ - norms are proved rigorously. Finally, we present a numerical example to verify the effectiveness of our algorithm.

The exploration of thermally chargeable supercapacitors has gained intensive interest. However, their practical application is still restricted by complex integration, poor Seebeck coefficient, and unsatisfactory conversion efficiency. Herein, we report a high-performance device with a simplified symmetric configuration based on activated carbon derived from elm bark mucus. Due to high specific surface area, hierarchical porosity, and moderate surface chemistry, such system displays excellent electrochemical properties such as high capacitance, rate capability and thermoelectrical behavior. When coupling with a concentrated electrolyte (26 m KOAc), a 2.0 V symmetric supercapacitor can be fabricated and a maximum energy density of 33.6 Wh kg−1 at power density of 500 W kg−1. A high-power density of 20 kW kg−1 also can be achieved at 21.7 Wh kg−1. Moreover, thermally rechargeable devices with quasi solid-state electrolyte exhibit a high open circuit voltage of ∼24.02 mV and a considerable Seebeck coefficient of about 1.97 mV K−1, indicating satisfying thermoelectrical performances. This work not only demonstrates the applicability of elm bark mucus-derived carbon as advanced materials for energy application, but also provides a new perspective for the development of multifunctional devices.

In this paper we model the mesoscale crystallization of the crystals F e ( O H ) 3 in the dilute solution concentration in the sense that the microscale model is a stochastic process and meanwhile ...

This paper is concerned with a DC composite programs with infinite DC inequalities constraints. Without any topological assumptions and generalized increasing property, we first construct some new regularity conditions by virtue of the epigraph technique. Then we give some complete characterizations of the (stable) Fenchel-Lagrange duality and the (stable) Farkas-type assertions. As applications, corresponding assertions for the DC programs with infinite inequality constraints and the conic programs with DC composite function are also given.

The generalized diffusion equation with a delay has inherent complex nature because its analytical solutions are hard to obtain. Therefore, one has to seek numerical methods, especially the high-order accurate ones, for their approximate solutions. In this paper, we have established the results of the numerical asymptotic stability of the compact θ -method for the generalized delay diffusion equation. It shows that the compact θ -method is asymptotically stable if and only if ( k + r ) Δ t h 2 10 − cos ( h ) 12 ( 1 + cos ( h ) ) ( 1 − 2 θ ) for θ ∈ [ 0 , 1 2 ) and is unconditionally asymptotically stable for θ ∈ [ 1 2 , 1 ] , respectively. The convergent results in the maximum norm are studied according to the consistency analysis and Lax theorem. In the end, a series of numerical tests on stability and convergence are carried out to support our theoretical results.

The intercalation pseudocapacitive anode material TiNbxOx+2.5x (x = 2,5,24) has attracted much attention owing to its high theoretical specific capacity (388–402 mAh g−1) and relatively safe working voltage. However, Ti4+/Nb5+ has a 3d/4d empty orbital that leads to a lower electronic conductivity, which limits its practical application. Therefore, reasonable design and adjustment of an effective electron/ion transfer path is the key to the realization of high-performance anode material, which is of great significance to improve the multiplier performance and cycle life for lithium-ion batteries. In this work, we employ a facile electrospinning and subsequent hydrogenation process to synthesize one-dimensional TiNb24O62 (H-TNO) nanowires with oxygen vacancies. The rapid Li+ diffusion path and high Li+ diffusion coefficient are achieved by nano engineering, besides, hydrogen treatment brings oxygen vacancy to improve the electronic conductivity, together with providing more Li+ active sites for TNO materials. As a result, the as-prepared H-TNO-1h (treatment with 1 h) electrode delivers a high reversible specific capacity (305.2 mAh g−1 at 0.1 A g−1), safer working voltage (~ 1.7 V vs. Li/Li +), high initial Coulombic efficiency (91.9%), excellent rate properties (180.5 mAh g−1 at 5 A g−1) and superior cycle stability, making it become one of the best choices in titanium niobium electrode material used for lithium-ion batteries.

In this report, we give an equivalent reformulation for the complementarity equation of the semidefinite optimization. By the equivalent reformulation, we present and analyze a non-interior Newton method. This method can start from an arbitrary initial matrix. We also give a simple numerical result to testify its efficiency.

Background Valproic acid (VPA), a widely used antiepileptic drug, has a narrow therapeutic range of 50-100 mcg/mL and shows large individual variability. It is very important to monitor the trough concentration of VPA using a reliable method. Therefore, the aim of this study was to develop and validate a rapid ultraperformance liquid chromatographic-mass spectrometry (UPLC-MS) method for quantification of VPA in human serum and to compare with fluorescence polarization immunoassay (FPIA), chemiluminescence microparticle immunoassay (CMIA), and high-performance liquid chromatography (HPLC) methods. Methods The method included extraction of VPA in serum by deproteinization with acetonitrile. The analysis was performed using an EC-C18 column (2.7 μm, 4.6 × 50 mm) under isocratic conditions with a mobile phase of acetonitrile/water (containing 0.1% formic acid) (45/55, vol/vol) at a flow rate of 0.6 mL/min. The detection was performed on a triple-quadrupole tandem mass spectrometer using an electrospary probe in the negative ionization mode. The method was validated by studies of selectivity, linearity, lower limit of quantification, accuracy, precision, recovery, matrix effect, and stability. Furthermore, all the 4 methods including FPIA, CMIA, and HPLC were subsequently used to assay the VPA concentration in 498 clinical serum samples collected from patients who received VPA. These methods were compared by Deming regression and Bland-Altman analysis. Results The retention time of VPA was 2.09 minutes. The calibration curve was linear over the concentration range of 1-200 mcg/mL, with a lower limit of quantification of 1 mcg/mL. The interday and intraday precision (RSD %) was less than 4.6% and 4.5%, respectively, and the accuracy (RE %) was below 7.9%. The recoveries and matrix effect of VPA at concentrations of 2, 50, and 160 mcg/mL met the requirement for the analysis of biological samples. No obvious degradation of VPA was observed under various storage conditions including room temperature for 12 hour, 3 freeze-thaw cycles, and -20°C for 3 months. Regression analysis showed that the correlation coefficients for the UPLC-MS versus FPIA, CMIA, and HPLC were 0.989, 0.988, and 0.987, respectively. The results of agreement tests between UPLC-MS and other methods showed that the mean difference of UPLC-MS and FPIA was -1.4 mcg/mL and 95% confidence interval of -7.7 to 4.9 mcg/mL, and the values for UPLC-MS and CMIA were -0.8 mcg/mL and -7.5 to 5.8 mcg/mL, for UPLC-MS and HPLC were 1.1 mcg/mL and -5.7 to 7.9 mcg/mL. Conclusion The rapid UPLC-MS method we developed showed a good analytical performance required for therapeutic drug monitoring, leading to potential improvements in patient care and laboratory management. Compared with the FPIA, CMIA, and HPLC methods, the UPLC-MS method correlated well and displayed comparable VPA concentrations.

We adopt the self-adaptive strategy to update the barrier parameter of a feasible primal-dual interior-point algorithm. We obtain two adaptive updating methods, namely, cheap updates and sharp updates. We compare the effectiveness of the short updates with the adaptive update methods on some benchmark problems. The numerical results show that the sharp updates method is superior to short updates and cheap updates methods.