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Organic field-effect transistors with parallel transmission and learning functions are of interest in the development of brain-inspired neuromorphic computing. However, the poor performance and high power consumption are the two main issues limiting their practical applications. Herein, we demonstrate an ultralow-power vertical transistor based on MXene and organic single crystal. The transistor exhibits a high J

Objective: Diet acidification supplementation is known to influence intestinal morphology, gut microbiota, and on phosphorus (P) utilization of broilers. Alterations in intestinal barrier and microbiota have been associated with systemic inflammation and thus regulating bone turnover. Hence the effect of acidifier addition to drinking water on tibia mass and the linkages between intestinal integrity and bone were studied.Methods: One-d-old male broilers were randomly assigned to normal water (control) or continuous supply of acidified water (2% the blend of 2-hydroxy-4-methylthiobutyric acid, lactic, and phosphoric acid) group with 5 replicates of 10 chicks per replicate for 42 d.Results: Acidification of drinking water improved the ash percentage and calcium content of tibia at 42 d. Broilers receiving acidified water had increased serum P concentration compared to control birds. The acidified group showed improved intestinal barrier, evidenced by increased wall thickness, villus height, the villus height to crypt depth ratio, and upregulated mucin-2 expression in ileum. Broilers receiving drinking water containing mixed organic acids had a higher proportion of Firmicutes and the ratio of Firmicutes and Bacteroidetes, as well as a lower population of Proteobacteria. Meanwhile, the addition of acidifier to drinking water resulted in declined ileal and serum proinflammatory factors level and increased immunoglobulin concentrations in serum. Concerning bone remodeling, acidifier addition was linked to a decrease in serum C-terminal cross-linked telopeptide of type I collagen and tartrate-resistant acid phosphatase reflecting bone resorption, whereas it did not apparently change serum alkaline phosphatase activity that is a bone formation marker.Conclusion: Acidified drinking water increased tibia mineral deposition of broilers, which was probably linked with higher P utilization and decreased bone resorption through improved intestinal integrity and gut microbiota and through decreased systemic inflammation.

Purpose This paper aims to propose a characteristic stabilized finite element method for non-stationary conduction-convection problems. Design/methodology/approach To avoid difficulty caused by the trilinear term, the authors use the characteristic method to deal with the time derivative term and the advection term. The space discretization adopts the low-order triples (i.e. P1-P1-P1 and P1-P0-P1 triples). As low-order triples do not satisfy inf-sup condition, the authors use the stability technique to overcome this flaw. Findings The stability and the convergence analysis shows that the method is stable and has optimal-order error estimates. Originality/value Numerical experiments confirm the theoretical analysis and illustrate that the authors’ method is highly effective and reliable, and consumes less CPU time.

二维共轭聚合物具有平面共轭结构和分子中离域的π电子体系, 因而具有很强的平面内电荷传输能力, 表现出独特的物理和化学性质, 在光学、电学、传感等领域具有广阔的应用前景. 但如何获得分子结构及形貌符合二维特征、且尺寸满足制作电子器件需求的分子非常困难, 是广大科研人员急需解决的问题. 本文总结了界面合成二维共轭聚合物的方法, 讨论了这个领域目前面临的问题和挑战, 并指出了未来的研究方向.

There is very limited repertoire of organic ambipolar semiconductors to date. Electron donor-acceptor alternative stacking is a unique and important binary motif for 1D mixed-stack cocrystals, opening up possibilities for the development of organic ambipolar semiconductors. Herein, four 1D mixed-stack cocrystals using N,N'-bis(perfluorobutyl)-1,7-dicyanoperylene-3,4:9,10-bis(dicarboximide) (PDICNF) as the acceptor and anthracene, pyrene, perylene, and meso-diphenyl tetrathia[22]annulene[2,1,2,1] (DPTTA) as the donors are achieved in a stoichiometric ratio (D:A = 1:1) through solution or vapor processed methods. Their packing structures, energy levels, charge transfer interactions, coassembling behaviors, and molecular orientations are systematically investigated by single-crystal X-ray analysis, absorption spectra, fluorescence quenching, Job's curve plot, and polarized photoluminescence measurements with the help of theoretical calculations. The donor-acceptor alternative stacking direction coincides with the long axis for all the four cocrystals. The field-effect transistors based on Pyrene-PDICNF show the electron mobility up to 0.19 cm2 V-1 s-1 , which is the highest value among perylene diimide-based cocrystals. Moreover, DPTTA-PDICNF cocrystals possess well-balanced electron and hole mobility with 1.7 × 10-2 and 2.0 × 10-2 cm2 V-1 s-1 respectively due to both hole and electron strong superexchange interactions, shedding light on the design of 1D mixed-stack cocrystals with excellent ambipolar transport behaviors.

Model uncertainty is an important issue that must be considered when designing or analyzing controllers. So focusing on a class of nonlinear systems with model uncertainties, this paper analyzed the tracking performance of the active disturbance rejection controller with a high-gain observer, through transforming the model uncertainties into the error form, and the closed-loop system was proved to be ultimately bounded using Lyapunov function and Gronwall-Bellman inequality. Finally, numerical simulations demonstrate the results.

Preparing two-dimensional conjugated polymers (2DCPs) with desirable structures and semiconducting properties is promising but remains a great challenge. Presented here is a new 2DCP, named 2D polytriethyltriindole (2DPTTI), which is efficiently synthesized by a modified interfacial Suzuki reaction from 2,7,12-tribromo-5,10,15-triethyltriindole (2-BrTTI) and 1,4-benzenediboronic acid dipinacol ester (BADE) precursors at room temperature. Wafer-scale free-standing 2DPTTI films with controllable thicknesses between 2.5 and 46.0 nm were obtained by adjusting the experimental conditions. The resulting 2DPTTI films, used as an active layer in organic field effect transistors (OFETs), exhibited typical p-type semiconducting properties and superior UV optoelectronic performance with a photosensitivity of 3.7×103 and responsivity of 1.4×103 A W-1 , as well as a light-blue fluorescence character. This report provides a general approach for constructing various semiconducting 2DCPs, by an interfacial Suzuki reaction, towards multifunctional organic electronics.

In this study, embedded strain sensors based on the principle of piezoresistivity were fabricated by epoxy-based composites filled with different contents of carbon nanofibers (CNFs). The piezoresistive performances and relevant parameters including gauge factor, linearity, repeatability and hysteresis of these sensors were investigated. A compensation circuit was proposed to eliminate the influence of temperature on sensing signals of the sensors. The CNFs/epoxy sensors were embedded into concrete cylinders to monitor their compressive strains under monotonic and cyclic loadings, thereby assessing practical applications of the CNFs/epoxy sensors as strain sensors for monitoring concrete structures. The results indicate that the sensors containing 0.58 vol% of CNFs, which have a gauge factor of 37.1, a linearity of 5.5%, a repeatability of 3.8% and a hysteresis of 6.3%, exhibited better piezoresistive performance compared to those containing 0.29 vol% of CNFs. The calibration and monitoring curves exhibited a consistent variation trend when the cylinders embedded with sensors were subjected to monotonic and cyclic loadings. This demonstrates that the CNFs/epoxy sensors have considerable potential to be used as embedded strain sensors for structural health monitoring of concrete structures.

This study investigated the strain and damage self-sensing capabilities of basalt fiber reinforced polymer (BFRP) laminates fabricated with carbon nanofibers (CNFs)/epoxy composites subjected to tensile loadings. The conduction mechanisms based on the tunnel conduction and percolation conduction theories as well as the damage evolution were also explored. A compensation circuit with a half-bridge configuration was proposed. The results indicated the resistivity of the CNFs/BFRP laminates and CNFs/epoxy composites exhibited similar change rule, indicating that the conductive networks of CNFs/BFRP laminates were governed by CNFs/epoxy composites. With the increase of strain under monotonic tensile loading, the electrical resistance response could be classified into three stages corresponding to different damage modes. This confirmed CNFs/BFRP laminates have excellent self-sensing abilities to monitor their internal damages. Moreover, stable and repeatable strain self-sensing capacity of the CNFs/BFRP laminates was verified under cyclic tensile loading because the electrical resistance varied synchronously with the applied strain.

To quantitatively investigate the correlation between parameters, disturbance and stability of the linear active disturbance rejection control (LADRC) technique, this paper provides a perspective of first-order nonlinear dynamic systems, and obtains the stable region of LADRC and reduced-order LADRC according to the Lyapunov function and the Markus–Yamabe theorem, along with mathematical proofs for global stability and asymptotic regulation. To be specific, regardless of whether plant dynamics are exactly known or unknown, the control bandwidth can be chosen arbitrarily from the obtained feasible region as long as the derivative of the disturbance satisfies a Lipschitz condition, or some knowledge of the boundary is available. Moreover, simulations are presented to testify the reliability of the results for different disturbances that are probably known or unknown when designing the extended state observer. The results show the validity and feasibility of this analysis.

Sodium-ion hybrid supercapacitors have received great attracts for next-generation energy storage applications due to their high energy and power densities, as well as the abundant sodium resource. However, electrodes based on transition-metal oxides often suffer from low reversible capacity and sluggish redox kinetics, which seriously constrains the rate and cycling performance of the devices. Herein, a facile two-step hydrolysis synthesis is used to prepare uniform sandwich-like mesoporous Nb2O5/graphene/mesoporous Nb2O5 (G@mNb2O5) nanosheets as sodium storage materials. The mesoporous Nb2O5 layers on graphene are constructed by several nanometer-sized Nb2O5 particles. In virtue of the structural features, the G@mNb2O5 nanosheets electrode demonstrates high-rate capacity (293 and 125 mA h g−1at 50 and 2000 mA g−1, respectively) and stable cycling performance due to the rapid redox kinetics, including significantly increased surface pseudocapacitive contribution, improved sodium-ion diffusion coefficient, and short characteristic relaxation process. By employing activated carbon as cathode, a full sodium-ion hybrid device successfully demonstrates a high energy density of 56.1 Wh kg−1 at 120 W kg−1, and 9.7 Wh kg−1 at 7200 W kg−1, as well as a stable capacitance retention of ∼ 89% at 1 A g−1. The availability of capacitive Na-ion storage system presented here is attractive for cost-effective energy storage applications.

In this study, AZ31 magnesium alloy plates with fine grained microstructure were processed by cold dynamic extrusion followed by low temperature annealing. The corresponding microstructure evolution and mechanical properties were systematically investigated, with a great emphasis on the effect of high {10−12} extension twin density. Profuse {10–12} extension twin and nanograined structure was generated in various regions after 20% cold dynamic extrusion. Thus, pre-twinning greatly improved the strength and ductility in magnesium alloy. In addition, the introduction of high twin density can be an effective way to improve mechanical properties of magnesium alloy via twin-dislocation interaction during plastic deformation. With mechanical behavior properly described, high twin density increases the uniformity of localized dislocation plasticity, thereby improving the strain hardening property. Also, we conclude that high strain rate in cold dynamic extrusion can be considered as an effective method for preparation of pre-twinning magnesium alloy, which exhibits good mechanical properties.

In this study, one new rare-earth lanthanum(Ⅲ) metal-organic coordination polymer {[La(L)1.5(H2O)(DMF)]∙DMF}n (H2L = 4,4’-(diethynylanthracene-9,10-diyl) dibenzoic acid) labeled as La-CP was successfully constructed via a solvothermal process. Structure analysis of the obtained La-CP revealed that it crystallized in the triclinic space group P-1, in which each La3+ ion was coordinated to eight oxygen atoms to form a distorted square antiprism geometry. It was important to observe π-π stacking between adjacent ligand moieties of La-CP with face-to-face distances of 3.385 and 3.447 A, endowing charge carriers with the possibility of through-space transport. The optical band gap of 2.23 eV evaluated from the UV-vis diffuse reflectance spectrum, coupled with electronic band structure calculation, provided reliable evidence of its potential semiconductor characteristic. In addition, La-CP exhibited a yellow fluorescence emission and a comparable quantum yield of 1.81% to that of free ligand H2L in terms of its optical properties. This work not only expands the list of rare-earth lanthanide coordination polymers but also offers useful guidance for materials design and related properties modulation of coordination polymers to some extent.

The ability to detect light in photodetectors is central to practical optoelectronic applications, which has been demonstrated in inorganic semiconductor devices. However, so far, the study of polarization-sensitive organic photodetectors, which have unique applications in flexible and wearable electronics, has not received much attention. Herein, the construction of polarization-sensitive photodetectors based on the single crystals of a superior optoelectronic organic semiconductor, 2,6-diphenyl anthracene (DPA), is demonstrated. The systematic characterization of two-dimensionally grown DPA crystals with various techniques definitely show their strong anisotropy in molecular vibration, optical reflectance and optical absorption. In terms of polarization sensitivity, DPA-crystal based photodetectors exhibit a linear dichroic ratio up to ≈1.9. Theoretical calculations confirm that intrinsic linear dichroism, originated from the anisotropic in-plane crystal structure, is responsible for the polarization sensitivity of DPA crystals. This work opens up a new door for exploiting organic semiconductors for developing highly compact polarization photodetectors and providing new functionalities in novel flexible optical and optoelectronic applications.

Paris Saponin II (PSII) has been shown anticancer activity against several cancer lines through the pro-apoptotic pathway. The aim of the study was to investigate the relationship between apoptosis and autophagy taking part in the anti-cancer mechanisms of PSII. In this study, PSII induced autophagy and apoptosis in dose- and time-dependent manners. Meanwhile, it induced autophagy as early as 2 h after exposure to 1 μM of PSII accompanying with apoptosis. Blockade of autophagy with chloroquine (CQ) attenuated apoptosis, while regulation of reactive oxygen species (ROS) by N-acetyl cysteine (NAC), gallic acid (GA) and H2O2 could not influence autophagy. In addition, PSII induced apoptosis via activation of autophagy, which might be associated with the activation of JNK and inhibition of PI3K/AKT/mTOR pathway. All in all, our research increased the understanding of the role of PSII regulating autophagy and apoptosis, which would hopefully provide prospective strategies for cancer therapy.

This article proposes a stabilized mixed finite element method to investigate the stationary Stokes-dual-permeability fluid flow model which couples the free flow region modeled by the Stokes equations and dual-porous medium modeled by the dual-permeability equations. The robust mixed finite element method developed here does not require any Lagrange multiplier but a mesh dependent stabilization term with a relaxation parameter is introduced essentially to ensure the numerical stability of the algorithm. The well-posedness and the optimal error estimate of the finite element scheme are derived. Furthermore, an iterative scheme is developed based on the traditional coupled algorithm. We prove that the iterative scheme converges to the coupled scheme, and the rate of convergence is estimated. The feature of the model is illustrated by considering five numerical examples which reveal the applicability of the fluid flow model as well as the accuracy of the numerical method.

In this study, conductive carbon nanofibers (CNFs) were dispersed into epoxy resin and then infused into glass fiber fabric to fabricate CNF/glass fiber-reinforced polymer (GFRP) laminates. The electrical resistance and strain of CNF/GFRP laminates were measured simultaneously during tensile loadings to investigate the in situ strain and damage monitoring capability of CNF/GFRP laminates. The damage evolution and conduction mechanisms of the laminates were also presented. The results indicated that the percolation threshold of CNFs content for CNF/GFRP laminates was 0.86 wt % based on a typical power law. The resistance response during monotonic tensile loading could be classified into three stages corresponding to different damage mechanisms, which demonstrated a good ability of in situ damage monitoring of the CNF/GFRP laminates. In addition, the capacity of in situ strain monitoring of the laminates during small strain stages was also confirmed according to the synchronous and reversible resistance responses to strain under constant cyclic tensile loading. Moreover, the analysis of the resistance responses during incremental amplitude cyclic tensile loading with the maximum strain of 1.5% suggested that in situ strain and damage monitoring of the CNF/GFRP laminates were feasible and stable.

In the process of modern industrial control, systems with large time-delay are typical problems. Thus in order to get better control effect, it is productive by combining advanced control methods with traditional Smith predictor. The aim of this paper is to present the LADRC(linear active disturbance rejection control)-Smith controller design and parameters analysis for first-order inertial systems with large time-delay, along with the discussion of frequency response and parameters perturbation for systems. To be specific, it is proved that the system is stable when parameters of plant are exactly known. Moreover, a sufficient stable condition is obtained when parameters of plant change. Besides, the step response, stability margin and capability of disturbance rejection are compared when the plant has a different degree of perturbation, and these results make great sense to design the LADRC-Smith controller and regulate parameters for time-delay systems.

Interface engineering has emerged as a fertile and efficacious approach to turn functional properties in the field of film systems. In this work, the interfacial properties of sputtered yttrium oxide films on zinc sulfide substrate (Y 2 O 3 /ZnS) were analyzed by transmission electron microscopy (TEM), X-ray photoelectron spectrum (XPS) depth profile and nano-scratch measurement. An interface layer with the depth of 20 nm between Y 2 O 3 film and ZnS substrate was directly observed by TEM. Under different film growth conditions, although the interfacial features including interfacial width and composition distribution exhibit similar behavior, it is found that higher cohesive strength is obtained under a special substrate bias voltage of −160 V at low substrate temperature. Such an enhanced mechanical property can be understood by the role of physisorbed oxygen in the interfacial region, in which less physisorbed oxygen with van der Waals bonds leads to a strong adhesion. Our results provide a favorable strategy to achieve strong adhesion between oxide and sulfide at low temperature, which are urgent in future micro-electric applications.

This study presents the design and cold testing of a Q-band TE01-mode converter. Integrating Marie transducer and the design of Ching-Fang Yu and Tsun-Hsu Chang, we have improved the design of circular TE01-mode converter. The working principle of each section are analyzed and discussed. Two identical converters are joined back-to-back to explore the field symmetry and to examine the existence of competing modes. The angle-independent transmissions manifest high mode purity. This converter features high back-to-back converting efficiency, high mode purity, compact converting section , and broad bandwidth (18% at a 1-dB transmission).

A new method was found to synthesize large-area (7 × 15 mm2), high-density (higher than 109 cm−2), aligned carbon nanotubes (CNTs) with uniform diameters on a silica wafer. Ferrocene/melamine mixtures were pyrolyzed through a three-step process in an Ar atmosphere in a single-stage furnace. The structure and composition of the CNTs were investigated by scanning electron microscopy, transmission electron microscopy (TEM), x-ray photoelectron spectroscopy (XPS), and electron energy-loss spectroscopy (EELS). It was found that these nanotubes have uniform outer diameters of about 22 nm and varying lengths from 10 to 40 μm. High-resolution TEM images showed that CNT is composed of graphite-like layers arranged in a stacked-cup-like structure. XPS results showed that the layer covering the tops of the aligned CNTs consists of carbon and iron. The EELS spectrum showed that these tubes are pure carbon.

A new technique for designing millimeter-wave 11.25o digital phase shifter circuit is presented. The proposed phase shifter were fabricated using a tandem stubs phase shifter for 11.25o at Ka-band. In the operating frequency from 30GHz to 31GHz, the VS WR of the phase shifter is less than 1.65, the insertion loss is less than 3dB, the phase shift is fixed around 11.25° and its accuracy is up to ±3 °.