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As nitric oxide (NO) plays significant roles in a variety of physiological processes, the capability for real-time and accurate detection of NO in live organisms is in great demand. Traditional assessments of NO rely on indirect colorimetric techniques or electrochemical sensors that often comprise rigid constituent materials and can hardly satisfy sensitivity and spatial resolution simultaneously. Here, we report a flexible and highly sensitive biosensor based on organic electrochemical transistors (OECTs) capable of continuous and wireless detection of NO in biological systems. By modifying the geometry of the active channel and the gate electrodes of OECTs, devices achieve optimum signal amplification of NO. The sensor exhibits a low response limit, a wide linear range, high sensitivity, and excellent selectivity, with a miniaturized active sensing region compared with a conventional electrochemical sensor. The device demonstrates continuous detection of the nanomolar range of NO in cultured cells for hours without significant signal drift. Real-time and wireless measurement of NO is accomplished for 8 d in the articular cavity of New Zealand White rabbits with anterior cruciate ligament (ACL) rupture injuries. The observed high level of NO is associated with the onset of osteoarthritis (OA) at the later stage. The proposed device platform could provide critical information for the early diagnosis of chronic diseases and timely medical intervention to optimize therapeutic efficacy.

This paper proposed LightSleepNet -a light-weight, 1-d Convolutional Neural Network (CNN) based personalized architecture for real-time sleep staging, which can be implemented on various mobile platforms with limited hardware resources. The proposed architecture only requires an input of 30s single-channel EEG signal for the classification. Two residual blocks consisting of group 1-d convolution are used instead of the traditional convolution layers to remove the redundancy in the CNN. Channel shuffles are inserted into each convolution layer to improve the accuracy. In order to avoid over-fitting to the training set, a Global Average Pooling (GAP) layer is used to replace the fully connected layer, which further reduces the total number of the model parameters significantly. A personalized algorithm combining Adaptive Batch Normalization (AdaBN) and gradient re-weighting is proposed for unsupervised domain adaptation. A higher priority is given to examples that are easy to transfer to the new subject, and the algorithm could be personalized for new subjects without re-training. Experimental results show a state-of-the-art overall accuracy of 83.8% with only 45.76 Million Floating-point Operations per Second (MFLOPs) computation and 43.08 K parameters.

Mg–Li based alloys have been widely used in various fields. However, the widespread use of Mg–Li based alloys were restricted by their poor properties. The addition of rare earth element in Mg–Li can significantly improve the properties of alloys. In the present work, different electrochemical methods were used to investigate the electrochemical behavior of Y(III) on the W electrode in LiCl–KCl melts and LiCl–KCl–MgCl2 melts. In LiCl–KCl melts, typical cyclic voltammetry was used to study the electrochemical mechanism and thermodynamic parameters for the reduction of Y(III) to metallic Y. In LiCl–KCl–MgCl2 melts, the formation mechanism of Mg–Y intermetallic compounds was investigated, and the results showed that only one kind of Mg–Y intermetallic compound was formed under our experimental conditions. Mg–Li–Y alloys were prepared via galvanostatic electrolysis, and XRD and SEM equipped with EDS analysis were used to analyze the samples. Because of the restrictions of EDS analysis, ICP-AES was used to analyze the Li content in Mg–Li–Y alloys. The microhardness and Young's modulus of the Mg–Li–Y alloys were then evaluated.

Objective Neuromodulatory anterior thalamic deep brain stimulation (DBS) is an effective therapy for intractable epilepsy, but few patients achieve complete seizure control with thalamic DBS. Other stimulation sites may be considered for anti‐seizure DBS. We investigated bilateral low‐frequency stimulation of the endopiriform nuclei (LFS‐EPN) to control seizures induced by intracortically implanted cobalt wire in rats. Methods Chronic epilepsy was induced by cobalt wire implantation in the motor cortex unilaterally. Bipolar‐stimulating electrodes were implanted into the EPN bilaterally. Continuous electroencephalography (EEG) was recorded using electrodes placed into bilateral motor cortex and hippocampus CA1 areas. Spontaneous seizures were monitored by long‐term video‐EEG, and behavioral seizures were classified based on the Racine scale. Continuous 1‐Hz LFS‐EPN began on the third day after electrode implantation and was controlled by a multi‐channel stimulator. Stimulation continued until the rats had no seizures for three consecutive days. Results Compared with the control and sham stimulation groups, the LFS‐EPN group experienced significantly fewer seizures per day and the mean Racine score of seizures was lower due to fewer generalized seizures. Ictal discharges at the epileptogenic site had significantly reduced theta band power in the LFS‐EPN group compared to the other groups. Interpretation Bilateral LFS‐EPN attenuates cobalt wire‐induced seizures in rats by modulating epileptic networks. Reduced ictal theta power of the EEG broadband spectrum at the lesion site may be associated with the anti‐epileptogenic mechanism of LFS‐EPN. Bilateral EPN DBS may have therapeutic applications in human partial epilepsies.

The electrode reaction of Pr(III) and coreduction of Pb(II) and Pr(III) were studied on an inert W electrode in eutectic LiCl-KCl to extract Pr from molten salt. The electrode process kinetic of Pr(III) on W electrode was firstly explored employing cyclic voltammetry (CV) and Tafel technique, such as the diffusion coefficient of Pr(III) in eutectic LiCl-KCl and the exchange current density (j0) for Pr(III)/Pr(0) couple and the electrode reaction activation energy. Then, various electrochemical techniques were used to investigate the coreduction of Pb(II) and Pr(III). Four cathode current peaks ascribed to the formation of PrxPby intermetallic compounds were detected, which indicated that the Pr could deposit on pre-deposited Pb film, react with Pb, and form PrxPby intermetallic compounds. Furthermore, the electrolytic products formed by galvanostatic electrolysis were characterized by scanning electron microscopy coupled with energy dispersive X-ray diffraction, which illustrated the formation of PrPb3 intermetallic compound in LiCl-KCl-PbCl2-PrCl3 melt.

High electromagnetic shielding performance was achieved in the Mg–9Li–3Al–1Zn alloy processed by accumulative roll bonding (ARB). The microstructure, electromagnetic interference shielding effectiveness (SE) in the frequency of 30–1500 MHz and mechanical properties of the alloy were investigated. A model based on the shielding of the electromagnetic plane wave was used to theoretically discuss the EMI shielding mechanisms of ARB-processed alloy. Results indicate that the SE of the material increases gradually with the increase in the ARB pass. The enhanced SE can be attributed to the obvious microstructure orientation caused by ARB, and the alternative arrangement of alpha(Mg) phase and beta(Li) phase. In addition, with the increase in ARB pass, the number of interfaces between layers increases and the grain orientation of each layer tends to alignment along c-axis, which is beneficial to the reflection loss and multiple reflection loss of the incident electromagnetic wave.

This paper proposes SaleNet - an end-to-end convolutional neural network (CNN) for sustained attention level evaluation using prefrontal electroencephalogram (EEG). A bias-driven pruning method is proposed together with group convolution, global average pooling (GAP), near-zero pruning, weight clustering and quantization for the model compression, achieving a total compression ratio of 183.11x. The compressed SaleNet obtains a state-of-the-art subject-independent sustained attention level classification accuracy of 84.2% on the recorded 6-subject EEG database in this work. The SaleNet is implemented on a Artix-7 FPGA with a competitive power consumption of 0.11 W and an energy-efficiency of 8.19 GOps/W., Comment: 5 pages, 4 figures, to be published in IEEE International Symposium on Circuits and Systems (ISCAS) 2022

This paper proposed a wearable smart sEMG recorder integrated gradient boosting decision tree (GBDT) based hand gesture recognition. A hydrogel-silica gel based flexible surface electrode band is used as the tissue interface. The sEMG signal is collected using a neural signal acquisition analog front end (AFE) chip. A quantitative analysis method is proposed to balance the algorithm complexity and recognition accuracy. A parallel GBDT implementation is proposed featuring a low latency. The proposed GBDT based neural signal processing unit (NSPU) is implemented on an FPGA near the AFE. A RF module is used for wireless communication. A hand gesture set including 12 gestures is designed for human-computer interaction. Experimental results show an overall hand gesture recognition accuracy of 91%.

With the depletion of terrestrial uranium deposits, a large amount of uranium(VI) (U(VI)) in seawater has attracted the attention of researchers and energy suppliers. However, the extremely low concentration of U(VI) and the complex environment enhance the difficulty of extracting U(VI) from seawater. In this study, a multi-active polyacrylonitrile (PAN) adsorbent was constructed to extract U(VI) from seawater. Poly(amido)amine (PAMAM) with hyperbranched topology was grown onto the surface of PAN fiber by a multi-step method, forming a swollen layer in water. The highest adsorption capacity of the material reached 555.5 mg/g. Importantly, during a continuous 50-day simulated seawater dynamic adsorption process, the material reached an adsorption equilibrium in 15 days, with the adsorption amount of 1.3 mg/g. The ocean test in the Yellow Sea of China showed that the adsorption capacity of the material was 0.6 mg/g in 34 days in seawater environment. The effect of molecular chain conformation and swelling behavior on adsorption properties were investigated. The study on the adsorption mechanism of the material shows that the lone pair of electrons of the N atom coordinates with U(VI).

As a duplex Mg–Li alloy, Mg–9Li–1Zn (LZ91) has attracted increasing attention, but its strength needs to be further improved. This paper aims to explore the effect of Y and Ce in different proportions on microstructures and mechanical properties of LZ91. The microstructures and mechanical properties of as-cast and cold-rolled LZ91 alloys with Y and Ce addition were investigated. The grain size of the LZ91 was refined due to the addition of Y and Ce. Y significantly strengthened LZ91 while Ce weakened the strengthening effect of Y. The mechanical properties increased first and then decreased with the content of Y and Ce, however, it still showed a strengthening effect compared to LZ91 alloys. The addition of Y caused the formation of Mg24Y5 and Mg12ZnY. With the addition of Ce, Mg12Ce and CeZn5 formed with a continuous-network distribution. Mg–9Li–1Zn-1.5Y exhibited the most excellent microstructure and mechanical properties in as-cast state (UTS, YS, and elongation are162MPa, 130 MPa and 49.6%, respectively) and cold-rolled state (UTS, YS, and elongation are 255 MPa, 231 MPa and 31.9%, respectively) states because of the prominent refinement effect of Y on α phase and the dispersion strengthening by Mg24Y5. Meanwhile, the elongation of Mg–9Li–1Zn-1.5Ce after cold rolling was abnormally enhanced. This was explained that the coarse Mg12Ce in the as-cast state was broken into fine dispersed particles after cold rolling. This paper provides a reference for the selection and quantification of rare earth elements in duplex Mg–Li alloys. It also provides a reference way to refine large-size second phases in duplex Mg–Li alloys.

The lack of flexibility of the substrates and the readily shed off of the active materials during the deformation process limit applications of wearable electronic devices. An effective approach is to design an electrode with both high flexibility and stability, which ensure that the device will not be affected in practical applications. In this paper, we design 3D Cu(OH)2 nanowires directly grown on carbon fiber cloth by a quasi-stable electroless Cu deposition and a rapid alkali assistant oxidation process. The Cu-electroless plating ensures high conductivity and excellent binding force between the active material and the substrate, which issued in low internal resistance and remarkable cycle stability. Moreover, the flexible all-solid-state asymmetric supercapacitor (FASSASC) assembled with the Cu(OH)2/CPCC (Cu-plated carbon cloth) as positive pole, possess high areal capacitances (242.5 mF cm−2 at 1 mA cm−2), relatively large energy and power density (4.9 × 10−2 mWh cm−2, 0.6 mW cm−2 respectively), with outstanding cycling stability and flexibility (90.5% capacitance retention after 5000 cycles under bending). Remarkably, we also assembled a self-charging power pack integrated of flexible all-solid-state asymmetric supercapacitors (FASSASCs) and commercial solar cells, which can capture energy from the sun, and then store it to furnish a durative and stable electrical output. Such a device could be powered by the self-charging function without time and location limit. These superior characteristics demonstrate that the Cu(OH)2/CPCC//AC/CC FASSASC a good candidate for next-generation flexible, wearable and portable electronic devices.

This paper proposed the design of a low-noise, low total harmonic distortion (THD) chopper amplifier for neural signal acquisition. A dc servo loop (DSL) based on active Gm-C integrator is proposed to reject the electrode-dc-offset (EDO). Architecture of a complementary input very low-transconductance (VLT) operational transconductance amplifier (OTA) was proposed and integrated in the active Gm-C integrator to improve the linearity as well as to reduce the noise, featuring a transconductance ranging from 45 pS to a few nS. The proposed amplifier was fabricated in a TSMC 0.18- $\mu \text{m}$ CMOS process, occupying an area of 0.2 mm 2, featuring a power consumption of $3.24~\mu \text{W}$ /channel under a 1.8-V supply voltage. The THD for a 5-mVpp input is lower than −61 dB. An input-referred thermal noise power spectral density (PSD) of 39 nV/ $\sqrt {\text {Hz}}$ is measured. The measured input-referred noise is $0.65~\mu \text {V}_{\text {rms}}$ in the 0.3–200-Hz frequency band and $2.14~\mu \text{V}_{\text {rms}}$ in the 200-Hz–5-kHz frequency band, respectively, leading to a noise-efficiency factor of 2.37 (0.3–200 Hz) and 1.56 (0.2 k–5 kHz). In addition, the high-pass corner frequency can be precisely configured and linearly adjusted with the external bias current from 0.35 to 54.5 Hz.

Superhydrophobic coatings have been applied in various fields because of their advantages such as self-cleaning, drag reduction, dustproof, anti-icing, corrosion resistant etc. However, in this study, a new idea imitating the process of growing grass was proposed to solve the low adhesion, weak wear resistance and poor corrosion resistance of the general superhydrophobic coatings: the ratio of epoxy resin to ZnO seeds were strictly controlled so that ZnO seeds are not completely coated. On this basis, a cluster-like ZnO coating composed of interdigitated ZnO rods was prepared. After modification with stearic acid, the coating exhibited superhydrophobic properties with a contact angle of 163° and the coating showed excellent abrasion resistance and noticeable robustness. Due to the barrier from both epoxy resin/ZnO seeds and cluster-like ZnO, the coating performed excellent corrosion resistance. At the same time, the cluster-like ZnO/epoxy resin coating prepared like seeds rooting has good firmness and can be adapted to various harsh environments such as tape peeling, friction between objects, etc., which can expand the application of the superhydrophobic coatings.

The microstructure and mechanical properties of TB8 cold-rolled plate with a thickness reduction of 50% during annealing at different temperatures are investigated. The results show that annealing for 1 h below 750 °C does not induce the recrystallization transition, remaining the main texture components of {001} , {113} and {112} . The ellipsoidal ω phase is formed when the alloy is annealed at 400 °C. α phase is formed when the alloy is annealed from 450 to 750 °C. The size and volume fraction of α phase increases first and then declines in control of driving force of phase transformation and diffusion. The synergistic effect of the precipitation of ω phase and α phase and the disappearance of dislocation makes the tensile strength of the plate decrease first, then increase, and finally decrease with the increase in annealing temperature. The change in plasticity is opposite to that of strength.

Uranium (VI) is very essential element in nuclear technique and the enrichment uranium has attracted lots of attention. In this work, l -Arginine and Ag nanoparticles (AgNPs) functionalized reduced graphene oxide ternary hydrogel composites (Ag- l -Arg-rGH) were successfully synthesized, which combined the insertion of AgNPs with one-step thermal reduction and an assembly of graphene oxide nanosheets, using l -Arginine ( l -Arg) as both a functional and cross-linking agents. The Ag- l -Arg-rGH composites exhibited great enhanced sorption capacity. Kinetic data best fitted the pseudo-second-order model. The thermodynamic data fitted the Langmuir isotherm model and the calculated maximum adsorption capacity is 434.78 mg/g. In addition, the anti-algae experimental results indicated adsorbent showed marked algal inhibition with the presence of AgNPs in the Ag- l -Arg-rGH composites. In the simulated seawater experiments, The distribution coefficient (Kd) value of uranium(VI) with other competing ions was 2.41 × 104 mL g−1. Thereby, the Ag- l -Arg-rGH composites possessed a promising potential for the enrichment uranium (VI) from nature seawater.

Al/Mg–Li/Al composite plates were fabricated by hot rolling with 50% thickness reduction at 673 K and annealed at 473–673 K for 1 h. The microstructure and mechanical properties of the composite plates under different annealing temperatures were investigated. The results show that the composite plates with a good bonding interface are fabricated. The diffusion layer consisting of Al3Mg2, Al12Mg17, AlLi, and MgLiAl2 has formed at the interface after annealing at and above 623 K, while the interfacial bonding strength increases with the annealing temperature. The microhardness of the interface increases rapidly when the annealing temperature is above 573 K. The elongation of the composite plate increases with annealing temperature. The tensile strength decreases when annealing temperature is above 573 K.

3D Ni-Multiwall carbon nanotubes/carbon nanofibers nanostructure has received many attentions due to the large specific surface and excellent electrochemical performance. The aggregation of CNTs and high-cost manufacturing are challenges facing the preparation of hybrid 3D Ni-MWCNTs/CNFs nanomaterials. In this article, MWCNTs have grown on electrospun CNFs by using low-cost reagents and an efficient production process. The direct growth of CNTs on electrospun CNFs completed via one-step process electrospinning of Ni (AC)/PVP/PAN solution and following CVD treatment. The hybrid 3D Ni-MWCNTs/CNFs showed a large surface area of 530 m2/g higher than Ni/CNFs of 375 m2/g. The diameter of the electrospun CNFs and grown CNTs about 150 and 20 nm of hierarchical 3D Ni-MWCNTs/CNFs observed by SEM and TEM images, respectively. The hybrid structure and full carbonization were confirmed by XRD and Raman spectrums. The 3D Ni-MWCNTs/CNFs showed a comparable gas sensing properties with high response and rapid response-recovery times versus Ni/CNFs, electrospun CNFs, and commercial CNTs at RT toward 100 ppb DMMP gas (Dimethyl methyl phosphonate is a simulant gas for sarin nerve agent) with excellent selectivity. In fact, the synthetic procedure promises to be an effective approach to synthesize the hybrid 3D CNTs/CNFs nanomaterials with high sensing performance.

In this work, we have successfully prepared cubic ZnSnO3/ZnO heterostructure composite (CZS/ZO) by a one-pot hydrothermal method. This composite easily forms a hollow structure through an alkali etching process while keeping its shape unchanged. The possible growth mechanisms have been studied and the material proves to have excellent gas sensing properties. The response of hollow cubic ZnSnO3/ZnO NPs (HZS/ZO) is up to 101 in 50 ppm triethylamine (TEA) gas at a working temperature of 160 °C; the lower limit of detection is 1 ppm. Moreover, the materials exhibit high selectivity and good stability. The role of ZnSnO3/ZnO n-n heterojunction in enhancing gas sensitivity is discussed.

The electrochemical formation of Ce-Ni alloy and its nucleation mechanism were researched in LiCl-KCl melts using different electrochemical methods. Cyclic voltammetric and square wave voltammetric results indicated that the electrochemical reduction of Ce (III) appeared at a less negative value on Ni electrode than that recorded on W electrode because of the formation of Ce-Ni alloy compounds. The nucleation mechanism of Ce was found to be the progressive nucleation on Ni electrode based on Scharifker-Hill model. The change of electrode surface morphology with deposited time was observed by SEM, which indicated that the morphology of Ce deposited on Ni electrode was dendritic. Ce-Ni alloys were prepared using potentiostatic electrolysis, and checked by XRD and SEM-EDS. The results showed that hydrogen storage alloys of CeNi2, CeNi3 and CeNi5 were gained by controlling applied potential. Furthermore, the thermodynamic properties of Ce-Ni compounds were estimated in the temperature range of 823–898 K by open circuit chronopotentiometry.

In this work, NiAl-LDH/Polypyrrole (NiAl-LDH/PPy) was synthesized by a simple method for the adsorption of uranium(VI) (U(VI)) from simulated seawater. The parameters studied contained pH, contact time, initial concentration and temperatures. The kinetic parameters showed that it could be well consistent with pseudo-second-order model. Langmuir and Freundlich isotherm models were used to describe the equilibrium data at three different temperatures (25, 35 and 45 °C). The result confirmed that the adsorption equilibrium tend to follow Langmuir isotherm model and the maximum adsorption capacity was evaluated to be 406.5 mg/g at 45 °C. The adsorption was a spontaneous endothermic process. NiAl-LDH/PPy also had good reproducibility and selectivity. In simulated seawater, NiAl-LDH/PPy composites showed a good enrichment effect for U(VI).

This session covers biomedical systems with innovations that traverse device, circuit, and system-level design. The first paper describes a retinal prosthetic that utilizes an optically-addressed nanowire array in conjunction with a transmitter-offloaded wireless neural stimulation approach for efficient operation near sensitive retinal tissue. A pneumatic-free fully-CMOS-controlled microfluidics platform for label-free cellular and bio-molecular sensing comes next, followed by a CMOS microscopic-scale thermal actuation and sensing array for localized heating of magnetic nanoparticles for hyperthermia cancer therapy. The final paper showcases a wireless multimode IC integrating electrochemical sensors, a temperature sensor, and a current stimulator for monitoring chronic wound healing processes.

A bio-potential recorder working under 0.8 V supply voltage with a tunable low-pass filter is proposed in this paper. The prototype is implemented in TSMC 180 nm CMOS technology, featuring a power consumption of 2.27 $\mu$ W, while preserving a high tolerance of power-line interference (PLI) up to 600 m $V_{pp}$ , a common-mode rejection ratio (CMRR) of higher than 100 dB, a THD of −65.5 dB, and a noise density of 50 nV/ $\sqrt{Hz}$ by employing four new techniques, including 1) low noise chopper modulator, 2) feedback loop based common-mode cancellation loop (CMCL), 3) offset cancellation loop (OCL) with PMOS backgate control scheme, and 4) a very-lower transconductance (VLT) operational transconductance amplifier (OTA) using in the DC-servo-loop (DSL). The measured mid-band gain is 43.3 dB with a high-pass cut-off frequency of 1.2 Hz. The low-pass cut-off frequency can be configured from 650 Hz to 7.5 kHz. The measured input-referred integrated noise is 1.2 uVrms in the frequency band of 1-650 Hz and 4.1 uVrms in the 1 Hz–7.5 kHz frequency band, respectively, leading to a power efficiency factor (PEF) of 7.49 and 7.59.

Real-time sensing of nitric oxide (NO) in physiological environments is critically important in monitoring neurotransmission, inflammatory responses, cardiovascular systems, etc. Conventional approaches for NO detection relying on indirect colorimetric measurement or built with rigid and permanent materials cannot provide continuous monitoring and/or require additional surgical retrieval of the implants, which comes with increased risks and hospital cost. Herein, we report a flexible, biologically degradable and wirelessly operated electrochemical sensor for real-time NO detection with a low detection limit (3.97 nmol), a wide sensing range (0.01–100 μM), and desirable anti-interference characteristics. The device successfully captures NO evolution in cultured cells and organs, with results comparable to those obtained from the standard Griess assay. Incorporated with a wireless circuit, the sensor platform achieves continuous sensing of NO levels in living mammals for several days. The work may provide essential diagnostic and therapeutic information for health assessment, treatment optimization and postsurgical monitoring., Real-time continuous sensing of biological analytes is of importance in a range of biomedical applications. Here, the authors report on a flexible and physically transient sensor for the detection of nitric oxide and demonstrate applications in nitric oxide sensing in organs ex vivo and in vivo.

A series of the rGO decorated hollow Co 3 O 4 spheres were fabricated via a solvothermal-combination-calcination process with no template. The morphological and crystal structure analysis were carried out through several characterization techniques, including SEM, TEM, XRD and XPS. The results indicate that the hollow Co 3 O 4 microspheres were assembled by nanoparticles with an average diameter of 20 nm and adhered uniformly on rGO nanosheets. According to the gas sensing test, 3 wt% rGO-Co 3 O 4 hollow spheres showed a higher substantial response to 100 ppm ethanol reaching up to 13.5, which is 3.7 times than the pristine Co 3 O 4 at 180 °C. In addition, it also exhibited short response-recovery time and good reproducibility. The enhanced sensing properties probably come from the synergy between rGO and Co 3 O 4 , mesoporous structure, and its high specific surface area (108.2 m 2 /g). This facile method could be used for the fabrication of many advanced materials for sensors, capacitors and electrodes.

Flexible and lightweight wire-shaped supercapacitors are important energy storage devices used for portable or wearable electronics. However, practical applications of flexible supercapacitors are still limited by the relatively poor performances. Herein, the hierarchical carbon cloth@CoMoO4@NiCo-LDH core-shell nanowire arrays supported have been synthesized via a facile two-step hydrothermal route coupled with annealing treatment. In addition, a possible mechanism for the growth of NiCo-LDH nanosheets (NSs) shell onto CoMoO4 nanowires (NWs) core is put forward based on the time-dependent experiments. The CC@CoMoO4@NiCo-LDH-12 h electrode exhibits a high specific capacitance of 2024 F g−1 at 1 A g−1, with 80.3% retention of the initial specific capacitance at 20 A g−1 and outstanding cycling stability. In addition, we have fabricated a flexible all-solid-state asymmetric supercapacitor (ASC) which achieves a maximum energy density of 59.5 Wh kg−1 at a power density of 800 W kg−1 and long-term cycling stability (89.7% device capacitance retention over 5000 cycles). The remarkable electrochemical performance can be ascribed to the rational combination of two electroactive materials and the reasonable array configuration.

As-cast Al-6.0Mg-0.4Mn-0.1Cr-0.1Zr alloys containing different additions of Er were prepared. Then, the specimens were carried out homogenization heat treatment, hot rolling, cold rolling, and annealing. The effects of minor Er on the microstructure and properties of Al-6.0Mg-0.4Mn-0.1Cr-0.1Zr alloy were investigated. Results show that addition of Er can refine the microstructure and improve the mechanical properties of the alloys. As for the annealed alloys, the addition of 0.33%Er can increase the tensile strength by 29 MPa. Strength increment is mainly attributed to refinement and the precipitation of Al3Er and Al3(Er, Zr). Additionally, the minor Er can improve the corrosion resistance of the alloys, which can be attributed to the compact composite oxide film of Er-O and Al-O, purification, and modification.

An innovative kind of low-temperature inorganic molten salt hybrid capacitor was first put forward. Mn2O3 nanoparticle was selected as battery type positive electrode of hybrid capacitor. The high crystallinity Mn2O3 nanoparticles with large specific surface areas were successfully prepared by molten salt synthesis method using ternary alkali nitrates. Electrochemical performances of Mn2O3 electrode were evaluated by cyclic voltammetry, square wave voltammetry, electrochemical impedance spectroscopy and galvanostatic charge/discharge in KNO3 (53 wt%)-NaNO2 (40 wt%)-NaNO3 (7 wt%) melts at 423 K. The results illustrated that Mn2O3 electrode transferred one electron during the reduction reaction and the Mn2O3 nanoparticle exhibited a high specific capacity of 669.6 C g−1 (186.0 mAh g−1, 2.51 F cm−2) at a current density of 5 mA cm−2. Furthermore, Mn2O3 electrode exhibited excellent cycle stability, and the capacity retention was up to 90.2% after 5000 cycles at a current density of 20 mA cm−2. The hybrid capacitors with molten salt electrolyte could be considered as a potential application in some specific situation which requires the high-temperature demand.

An Al-coated Mg-8 mass% Li alloy rectangular bar was fabricated by hot extrusion, and then, it was hot-rolled into a thin sheet. The Al coating was uniform in thickness and had good bonding with the substrate during all the processing. This Al-coated Mg–Li alloy exhibited a good corrosion resistance in a 0.5 mass% HCl aqueous solution. No intermetallic compound was observed at the Al/Mg–Li interface after the extrusion and the rolling. The Al-coated Mg–Li alloy sheet exhibited an elongation to fracture of 35% at room temperature at a strain rate of 0.001 s−1 without any debonding between the coating and the substrate. When tensile tested at 573 K at 0.001 s−1 in the air, the Al coating remained undamaged even until an elongation of about 150%. Further elongation generated cracks on the coating and the specimen fractured at an elongation of about 200%. In an Ar atmosphere, the specimen exhibited a fracture elongation of over 400% under the same conditions at 573 K at 0.001 s−1, although a large number of cracks generated on the Al coating.

AZ31 magnesium matrix composites reinforced by nickel coated graphene nanoplatelets (denoted as Mg-3wt.%Al-1wt.%Zn-0.5 wt% GNPs) were fabricated with vacuum hot-press sintering process. The sintered compacts were then hot extruded at 390 °C. The microstructure, mechanical properties and wear performance were investigated. The results show that, the nickel coated GNPs uniformly distribute in the matrix. The compressive strength, microhardness, the coefficient of friction and wear rate of the composites are noticeably improved, compared to the matrix alloy of AZ31. GNP content is the main factor affecting the wear behavior of composites, and the addition of GNPs resulted in a significant increase of the abrasion resistance and a decrease of the friction coefficient.

Effects of annealing temperature and annealing time on the microstructure, interfacial bonding properties and mechanical properties of alternate α/β Mg-Li alloy composite plates by accumulative roll bonding (ARB) were investigated. Due to the large reduction, a part of the relatively harder Mg-5Li-1Al alloy is embedded into the softer Mg-12Li-1Al alloy to achieve metallurgical bonding in the process of composite rolling. The optimum annealing temperature of the composite plate is 350 °C or 400 °C. At the same time, the formation mechanism of the interfacial diffusion region was discussed, and results show that there exist two diffusion regions, diffusion layer 1 and diffusion layer 2. The diffusion layer 1 is mainly composed of Li3Mg7 phase, and the diffusion layer 2 is composed of Li0.92Mg4.08 phase. The interfacial bonding ability of Mg-Li alloy composite plate first increases and then decreases with the increase of annealing temperature and annealing time. Compared with the composite plate processed by one pass ARB, the annealing time of the composite plate processed by six passes ARB increases due to the increase of cumulative strain, and the optimum annealing process is at 400 °C for 30 min.

The electrode reaction of Pb(II) and co-reduction of Li(I) and Pb(II) were investigated on a tungsten electrode in LiCl–KCl eutectic melts by a range of electrochemical techniques. From cyclic voltammetry and square wave voltammetry measurements, the reduction of Pb(II) was found to be a one-step diffusion-controlled reversible process with the exchange of 2 electrons. The diffusion coefficients of Pb(II) were computed, and they obey the Arrhenius law. Using the linear polarization technique, the kinetic parameters, such as exchange current intensity (j0), standard rate constant (k0) and charge transfer resistance (Rct) for the Pb(II)/Pb(0) couple on a tungsten electrode were studied at different temperatures, and the activation energy is 27.32 kJ mol−1, smaller than the one for diffusion of Pb(II), which further confirmed that the reduction of Pb(II) was controlled by diffusion. A depolarisation effect for Li(I) reduction was observed from the results of cyclic voltammetry, square wave voltammetry and chronopotentiometry due to the formation of Li–Pb alloys by co-reduction of Li(I) and Pb(II). Furthermore, five Li–Pb intermetallic compounds, LiPb, Li8Pb3, Li3Pb, Li10Pb3 and Li17Pb4 characterized by scanning electronic microscopy and X-ray diffraction, were selectively prepared by potentiostatic electrolysis on a tungsten electrode and galvanostatic electrolysis on a liquid Pb electrode, respectively.

This brief presents a wireless, low-power embedded system that recognizes hand gestures by decoding surface electromyography (EMG) signals. Ten hand gestures used on commercial trackpads, including pinch, stretch, swipe left, swipe right, scroll up, scroll down, single click, double click, pat, and ok, can be recognized in real time. Features from four differential EMG channels are extracted in multiple time windows. Unlike traditional data segmentation methods, an event-driven method is proposed, with the gesture event detected in the hardware. Feature extraction is triggered only when an event is detected, minimizing computation, memory, and system power. A time-delayed artificial neural network (ANN) is used to predict the gesture from the transient EMG features instead of traditional steady-state features. The ANN is implemented in the microcontroller with a processing time less than 0.2 ms. The detection results are sent wirelessly to a computer. The device weights 15.2 g. A 4.6 g battery supports up to 40 h continuous operation. To our knowledge, this brief shows the first real-time, embedded hand-gesture-recognition system using only transient EMG signals. Experiments with four subjects show that the device can achieve a recognition of ten gestures with an average accuracy of 94%.