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The anomalous Nernst effect (ANE), as a three-dimensional thermoelectric effect in ferromagnetic materials, is expected to break through the limitations of the traditional Seebeck effect, thereby improving thermoelectric conversion efficiency. This study reports an anisotropic anomalous Nernst effect in metallic nickel assembled by the alignment of nanowires. It is found that the ANE voltage varies with the angle to the alignment direction of nanowires within the in-plane of metallic nickel. The ANE voltage reaches 530 nV under a longitudinal temperature difference of 23 K when the magnetic field is applied parallel to the alignment direction of nanowires, which is 143% of its value in the vertical direction. This design concept for anisotropic materials may provide a novel path to enhanced thermoelectric efficiency in ANE-based thermoelectric devices. [ABSTRACT FROM AUTHOR]

Recent advances in wearable ultrasound technologies have demonstrated the potential for hands-free data acquisition, but technical barriers remain as these probes require wire connections, can lose track of moving targets and create data-interpretation challenges. Here we report a fully integrated autonomous wearable ultrasonic-system-on-patch (USoP). A miniaturized flexible control circuit is designed to interface with an ultrasound transducer array for signal pre-conditioning and wireless data communication. Machine learning is used to track moving tissue targets and assist the data interpretation. We demonstrate that the USoP allows continuous tracking of physiological signals from tissues as deep as 164 mm. On mobile subjects, the USoP can continuously monitor physiological signals, including central blood pressure, heart rate and cardiac output, for as long as 12 h. This result enables continuous autonomous surveillance of deep tissue signals toward the internet-of-medical-things. A wearable ultrasound patch monitors subjects in motion using machine learning and wireless electronics. [ABSTRACT FROM AUTHOR]

In this study, we showcase the use of silicon dioxide (SiO2) nanoparticles and hexamethyldisilazane (HMDS) treatment to regulate the thin film morphology and manipulate charge transport of solution-processed, small-molecular, organic semiconductors. 6,13-Bis(triisopropylsilylethynyl) pentacene (TIPS pentacene) was blended with SiO2 nanoparticles as an exemplary organic semiconductor. A higher concentration of SiO2 nanoparticles were observed near the edge of TIPS pentacene crystals and enlarged the width of crystal edges. This greatly reduced the dendritic crystal growth pattern of TIPS pentacene and contributed to its enhanced orientation uniformity. In addition, the HMDS treatment effectively passivated the silanol groups on the hydrophilic gate dielectrics. As a result, bottom-gate, top-contact TIPS pentacene/SiO2 nanoparticle-based organic thin-film transistors boosted a performance consistency enhancement (defined by the ratio of average mobility to the standard deviation of mobility). The combinational approach to employ SiO2 nanoparticles and HMDS treatment as demonstrated in this work sheds light on important applications in high-performance organic electronics devices on flexible substrate. [ABSTRACT FROM AUTHOR]

In this study, we report an effective approach to tune the crystallization, microstructure and charge transport of solution-processed organic semiconductors by blending with a conjugated polymer additive poly(3-hexylthiophene) (P3HT). When 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS pentacene) was used as a model semiconductor material to mix with different amount of P3HT, their intermolecular interactions led to distinctive TIPS pentacene film morphologies, including randomly-oriented crystal ribbons, elongated needles with enhanced long-range order, and grass-like curved microwires with interlinkages. Each type of morphology was found to further correlate to considerably different charge transport and device performance. As compared to pristine TIPS pentacene devices, bottom-gate, top-contact OTFTs with 2% in weight P3HT additive showed a 2-fold and 5-fold improvement of average field-effect mobility and performance consistency (defined as the ratio of average mobility to the standard deviation), respectively. The improvement in transistor electrical performance can be attributed to the combined effect of enhanced crystal orientation and uniformity, as well as increased areal coverage. This work can be applied beyond the particular example demonstrated in this study and to tune the charge transport of other small-molecule organic semiconductors in general. [ABSTRACT FROM AUTHOR]

In this work, we report for the first time the use of a nonconjugated semicrystalline polymer as a film-forming agent to control the crystallization and tune the charge transport of solution-processed, small-molecule organic semiconductors. When 6,13-bis (triisopropylsilylethynyl) pentacene (TIPS pentacene) was demonstrated as a representative material to blend with polyethylene oxide (PEO) polymer, it crystallized into uniformly-aligned needles with reduced random orientation, enhanced long-range order and elevated areal coverage. Specifically, an ultra-low misorientation angle of 7.9° ± 3.5° was obtained with 10% PEO additive, beneficial for charge transport in the TIPS pentacene/PEO hybrid film. Bottom-gate, top-contact organic thin film transistors (OTFTs) based on TIPS pentacene/PEO mixture were found to show a field-effect mobility up to 2.5 × 10−2 cm2/Vs. This work may be universally applied to other organic semiconductors to regulate their crystal formation, enhance film forming and improve device performance of OTFTs. It contributes to the utilization of flexible substrates for future-generation high-performance organic electronics. [ABSTRACT FROM AUTHOR]

In this work, we study for the first time the effect of a poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) polymer to control the crystal growth of solution-processed, small-molecule organic semiconductors and to improve the device performance of organic thin film transistors (OTFTs). A benchmark semiconductor 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS pentacene) was employed to blend with the polymer additive. The TIPS pentacene blend film with 5% PVDF-HFP by weight ratio exhibited a significant morphology enhancement with crystals strictly aligned in long-range order. In particular, it showed an average grain width of 69.98 μm and a misorientation angle of 6.6°, which is a 3.5-fold increase and a 7-fold reduction as compared to the pristine TIPS pentacene film. The bottom-gate, top-contact TIPS pentacene OTFTs with PVDF-HFP polymer additive were fabricated. Electrical characterization showed a hole mobility of up to 0.1 cm2/Vs with 5% PVDF-HFP. The performance improvement of TIPS pentacene/PVDF-HFP based OTFTs can be attributed to the reduced amount of charge trap centers at the enlarged grain width, alleviated crystal misorientation and increased areal coverage. This facile approach to blend PVDF-HFP additive to align crystals and improve orientation in long-range order as demonstrated in this work can be useful for controlling the crystallization and charge transport of other small-molecule organic semiconductors for application in organic electronics on large-scale flexible substrate. [ABSTRACT FROM AUTHOR]

Electrochemical metallization (ECM) cell kinetics are strongly determined by the electrolyte and can hardly be altered after the cell has been fabricated. Solid-state property tunable electrolytes in response to external stimuli are therefore desirable to introduce additional operational degree of freedom to the ECM cells, enabling novel applications such as multistate memory and reconfigurable computation. In this work, we use Ge2Sb2Te5(GST) as the electrolyte material whose solid state is switched from the amorphous(a) to the crystalline(c) phase thermally. Electrical heating too is readily achievable. The resistive switching characteristics of the cells with different GST phases are examined. The magnitude of the high resistance, the SET voltage and the on/off ratio are found to be considerably affected by the solid phase of GST, whereas the magnitude of the low resistance is least affected. Moreover, a transition from volatile to nonvolatile SET switching is only observed for c-GST based cell under prolonged voltage sweep, but not for a-GST based cell. This work provides a springboard for more studies on the manipulation of the ECM cell kinetics by tunable electrolyte and the resulting unprecedented device functionalities. [ABSTRACT FROM AUTHOR]

Owing to the unsustainability of traditional petroleum-based char-forming agents, cyclodextrin (CD) as the bio-based polyhydroxy compounds has been employed to construct the intumescent flame-retardant system with ammonium polyphosphate (APP) for flammable and fire-hazardous silicone rubber (SR). On the basis of this, the poor compatibility and water resistance of SR composites have been improved by separately introducing the bio-inspired hydrophobic structure for CD and APP. The results have implied that limiting oxygen index (LOI) and vertical combustion of SR composites with 40 phr total fillers loadings could reach 30.7% and UL-94 V-0 rating. Moreover, the water soaking tests have verified that the flame retardancy of SR composites could be maintained under hot aqueous medium. Based on thermogravimetric analysis (TGA), the reason for elevated flame retardancy of SR composites can be interpreted by good thermal stability and char-forming ability via the interaction of modified APP and CD. With the aid of analyzing combustion residues in details, the synergistic flame-retardant mechanism can be mainly elaborated as the gas phase dilution of inert gases and the condensed phase barrier of dense expanded carbon layer. Furthermore, the retained mechanical properties of SR composites via hydrophobic modification are beneficial to improve its application value. Thus, this paper has open up a novel, green and effective route for overcoming the crucial flame retardancy problem of SR materials in real-life applications. [ABSTRACT FROM AUTHOR]

Positive human–agent relationships can effectively improve human experience and performance in human–machine systems or environments. The characteristics of agents that enhance this relationship have garnered attention in human–agent or human–robot interactions. In this study, based on the rule of the persona effect, we study the effect of an agent's social cues on human–agent relationships and human performance. We constructed a tedious task in an immersive virtual environment, designing virtual partners with varying levels of human likeness and responsiveness. Human likeness encompassed appearance, sound, and behavior, while responsiveness referred to the way agents responded to humans. Based on the constructed environment, we present two studies to explore the effects of an agent's human likeness and responsiveness to agents on participants' performance and perception of human–agent relationships during the task. The results indicate that when participants work with an agent, its responsiveness attracts attention and induces positive feelings. Agents with responsiveness and appropriate social response strategies have a significant positive effect on human–agent relationships. These results shed some light on how to design virtual agents to improve user experience and performance in human–agent interactions. [ABSTRACT FROM AUTHOR]

Highlights: It is first disclosed that the key to the efficient regular Ag-perovskite solar cells (PSCs) is a tunneling layer (silver iodide, AgI) that is in situ formed by the natural reaction between Ag and the migrated iodide. Based on the discovery, an ultrathin and uniform tunneling layer can be deposited on the fragile perovskite/charge transport layer to enrich the options of electrodes for efficient and stable regular PSCs. Perovskite solar cells (PSCs) are taking steps to commercialization. However, the halogen-reactive anode with high cost becomes a stumbling block. Here, the halogen migration in PSCs is utilized to in situ generate a uniform tunneling layer between the hole transport materials and anodes, which enriches the options of anodes by breaking the Schottky barrier, enabling the regular PSCs with both high efficiency and stability. Specifically, the regular PSC that uses silver iodide as the tunneling layer and copper as the anode obtains a champion power conversion efficiency of 23.24% (certified 22.74%) with an aperture area of 1.04 cm2. The devices are stable, maintaining 98.6% of the initial efficiency after 500 h of operation at the maximum power point with continuous 1 sun illumination. PSCs with different tunneling layers and anodes are fabricated, which confirm the generality of the strategy. [ABSTRACT FROM AUTHOR]

The color of flour and its end-use products is an important quality trait of wheat. Understanding the genetic basis of this trait is essential for improving wheat quality. In this study, quantitative trait locus (QTL) mapping for 27 color-related traits of flour, starch, gluten, dough sheet, steamed bread, and baked bread was performed using a population of recombinant inbred lines (RILs) with 173 lines of F9:10, tested in four environments. For this purpose, a high-density genetic map constructed using a 90 K SNP array, Diversity Arrays Technology (DArT) and simple sequence repeat (SSR) markers was used. A total of 43 additive QTLs were detected, including 25 large-effect QTLs, located on chromosomes 1A, 1B, 2A, 4B, 5B, and 7B. Four of these major QTLs, namely QFa7B.7-1, QFb7B.7-2, QFb7B.7-1 and QGb4B.4, made the highest contribution and accounted for 29.60, 29.02, 27.45, and 22.24% of the phenotypic variation, respectively. Six stable QTLs (QSa4B.4, QSl4B.4-1, QFa7B.7-2, QFb7B.7-1, QFb7B.7-2, and QBca7B.7) were detected in more than one environment with high PVE values. In addition, two robust QTL clusters contribution to 13 evaluated traits were identified on chromosomes 4B (RAC875_c27536_611-wsnp_Ku_c28756_38667953) and 7B (wPt-1196-Kukri_c2348_2340). A locus within the interval Ex_c101685_705-RAC875_c27536_611 of 4B also harbored many genes previously reported to affect wheat quality and yield. These detected QTLs may be used for further study and be used to improve wheat quality in wheat-breeding programs. [ABSTRACT FROM AUTHOR]

SiO2-engineered nanoparticles (SiO2-ENPs) are one of the most commonly employed nanomaterials. There was a lack of research on the comprehensive effects of environmental factors on the stability of SiO2-ENPs. In the present work, the aggregation size, surface charge, and percentage of nanoparticles have been studied under the presence of monovalent/divalent cations combined with natural organic matter (NOM), in an effort to provide a comprehensive investigation of the stability of SiO2-ENPs in complex environmental conditions. Results show that NOM adsorbed to the particles and made their zeta potential more negative, hence stabilizing them by electrostatic repulsion, and the stability of nano-SiO2 in NOM solutions follows the order of pH 9 > pH 7 > pH 5. In addition, SiO2-ENPs size in solutions with humic acid (HA) was larger than that with fulvic acid (FA). The aggregation of SiO2-ENPs enhanced with the increase of cation concentrations, and divalent cations (Ca2+) show stronger influence on SiO2-ENPs aggregate than monovalent cations. Divalent cations partially neutralized the adsorbed organic matter, and aggregation was enhanced with Ca2+, suggesting the presence of specific Ca2+-NOM bridges. The aggregation of SiO2-ENPs in electrolyte (CaCl2 or NaCl) and CaCl2 + NOM solutions follows in the order of pH 5~pH 9 > pH 7, showing that weakly acidic or alkaline conditions are not favorable for the stability of SiO2-ENPs in complex environmental systems. [ABSTRACT FROM AUTHOR]

In this paper, a single-phase five-level active neutral-point-clamped with coupled inductors (ANPC-CI) rectifier topology is studied to meet the needs of efficient and reliable power electronic converters. A sliding mode model predictive power control method is proposed to achieve high-efficiency energy conversion, precise voltage control, and low harmonic distortion. By analyzing the working states, establishing a mathematical model and introducing the theory of instantaneous power, the outer loop sliding mode power control and the inner loop model predictive power control algorithms are designed. When compared with traditional PI-DPC algorithm, this algorithm avoids the tedious setting of parameters, reduces input power fluctuations, and improves the system dynamic response speed. The superiority of the sliding mode model predictive power control is verified by simulation and experimental results. [ABSTRACT FROM AUTHOR]

In this paper, two morphologies of crystalline Sb2S3 as dumbbell-like Sb2S3 and bundle-like Sb2S3 were synthesized by different phase-transformation of amorphous-to-crystalline, respectively. Different factors such as the variation of the solvent ratio, the surfactant, reaction temperature and reaction time were observed to obtain the key factor influencing the morphology. The bandgap of two Sb2S3 was obtained by diffused reflectance spectra and cyclic voltammetry. The charge separation was characterized by fluorescence spectrum, linear sweep voltammetry, transient photocurrent-time curve and electrochemical impedance spectrum. The results showed that bundle-like Sb2S3 had slightly higher light-harvesting and obvious higher charge separation ability, which was beneficial to the photodegradation of malachite green (MG). The photodegrdation path of MG implied the intermediates generated by bundle-like Sb2S3 were more easily decomposed to the small molecules. Bundle-like Sb2S3 displayed excellent reusability in the photodegradation of MG. Superoxide anion radical (·O2−) and hydroxyl radical (·OH) as the active species contributed to the photodegradation reaction. [ABSTRACT FROM AUTHOR]

Cyclic liquid nitrogen (LN2) fracturing is an innovative technology for reservoir stimulation with great potential in geothermal energy exploitation. Understanding of the mechanical responses of high-temperature rock to repetitive LN2 cooling at the laboratory scale is of great relevance to facilitate the field application of cyclic LN2 fracturing. In this work, granite samples were subjected to 0–24 heating–cooling cycles in two manners (i.e., slow heating to 300 °C followed by air cooling or LN2 cooling), and subsequent a series of laboratory tests with the aim of investigating the damage characteristics and mechanisms of rock samples after different heating–cooling cycles. The results concluded that increasing the number of cycles aggravates the internal structural damage of granite, which further deteriorates its physico-mechanical properties. Compared with air cooling, the cold shock effect of LN2 is more capable of facilitating the growth of microcracks within the rock, thereby inducing a more severe initial damage to granite sample. However, the damage of granite is prominent only in the first few cycles, and basically no longer intensified after more than about 12 cycles. This is related to the fact that the increase in micro-defects provides more space for thermal deformations of minerals and reduces the level of thermal stress within the rock. The results in this study are instructive for evaluating the effectiveness of cryogenic fracturing and determining the reasonable number of LN2 fracturing during reservoir stimulation. [ABSTRACT FROM AUTHOR]

A graphitic carbon nitride (g-C3N4/Fe3O4)–based magnetic solid-phase extraction (MSPE) approach was established for fast and simple analysis of estrogens in milk powders. The composites were characterized by X-ray diffractometer, scanning electron microscope, and Brunauer-Emmett-Teller surface area and pore size distribution analyzer. Compared with the bulk g-C3N4, g-C3N4/Fe3O4 gave a narrower distribution of mesopores and provided an enhanced surface area from 77.1 to 113.7 m2/g. Polar analytes of estrogens were selected as model compounds and the extraction of four estrogens was achieved in n-hexane using 15 mg of adsorbent within only 2 min. Possible extraction mechanism of g-C3N4/Fe3O4 for these estrogens was explored in terms of the polarity of the analytes and the adsorption performance of the adsorbent. The hydrophobicity and the hydrogen-bond interaction between the estrogens and g-C3N4 were responsible for the efficient adsorption. Combined with HPLC, MSPE with the prepared adsorbent gave the enhancement factors of 20 to 24 and the linear ranges of 2–200 μg/kg for 17β-estradiol and 17α-ethinylestradiol, 1.5–150 μg/kg for estrone, and 3–300 μg/kg for hexestrol. The detection limits and quantification limits for the estrogens in milk powders were 0.5–0.9 μg/kg and 1.5–3.0 μg/kg, respectively. The recoveries varied from 75.1 to 97.2%, with the intra-day and inter-day precisions ≤ 14.2%. Furthermore, the enrichment of the analytes and the clean-up of fat and protein interferences were achieved simultaneously with one-step g-C3N4-based MSPE. The present method was convenient, fast, and sensitive, and therefore could be successfully applied for the determination of estrogens in milk powders. [ABSTRACT FROM AUTHOR]

A comprehensive understanding of the physico-mechanical behavior of rocks in hot dry rock (HDR) reservoir after different stimulation treatments is essential for the safe and effective exploitation of geothermal energy. In this study, the physico-mechanical properties of high-temperature granite (25–600 °C) subjected to slow cooling, water cooling, and liquid nitrogen (LN2) cooling were experimentally investigated, and the damage evolution and damage mechanism of the rock were discussed from the macro- and microscopic perspectives. According to the experimental results, the increase in thermal treatment temperature aggravates the deterioration of the physico-mechanical properties of granite specimens. It is found that 400 °C is the threshold temperature of the tested granite, after which the physico-mechanical properties of the rock present more prominent changes. Since LN2 can induce a more intense thermal shock within rocks, it has the most significant damage to the specimens compared with other two cooling methods, especially at a higher thermal treatment temperature. Acoustic emission (AE) monitoring can well reflect the failure process and the associated microcrack behavior of the specimens during loading. The results of thin slice analysis indicate that the generation and extension of microcracks are responsible for the macro-properties degradation of rocks. Both grain boundary and intra-grain microcracks are more common near quartz boundaries and inside quartz grains. The results in this study would shed light on performing HDR reservoir stimulations assisted with cryogenic LN2. [ABSTRACT FROM AUTHOR]

Oxygen reduction reaction (ORR) is a crucial reaction for various energy conversion and storage devices, but the sluggish kinetics and the usage of noble metals greatly restrict its practical device applications. In this work, a well-designed high-performance catalyst for ORR was synthesized via a facile one-step Co-MOF carbonization method, in which Co-MOF was prepared using the cobalt acetate tetrahydrate and 2,2′-bipyridyl-5,5′-dicarboxylic acid (H2bpydc) as the only raw materials and H2bpydc as the favorable carbon and nitrogen source for in situ nitrogen doping and metallic cobalt reduction. The resultant 3D mesoporous carbon foam catalyst with embedded Co nanoparticles (CoN-CF) is enriched with nitrogen, which exhibits high specific surface area and abundant N-doping active sites for catalytic ORR. In particular, the optimized CoN-CF-700 sample displays the best catalytic performances including onset potential of 0.94 V, half-wave potential of 0.85 V, long-term durability and superior resistance to methanol poisoning. The demonstrated synthetic strategy provides a new insight into easy-synthesis and high-economy routes for metal-N-C catalysts and a deeper understanding of the effects of microstructures on catalytic mechanisms. [ABSTRACT FROM AUTHOR]

As a kind of medical service around people, community health care is closely related to peoples lives, and thus it has also been placed higher requirements. In the face of growing community medical needs, the construction and development of community medical Internet of things is imminent. Subsequently, massive multi-type of medical data which contain all kinds of user identity data, various types of vital signs data and other sensitive information are generated. Such a large scale of data in the transmission, storage and access process is facing the risk of data leakage. To effectively protect the privacy information of patients, an infrastructure framework for privacy protection of community medical Internet of things is proposed. It includes transmission protection based on multi-path asymmetric encryption fragment transmission mechanism, storage protection using distributed symmetric encryption cloud storage scheme and access control with identity authentication and dynamic access authorization. Through theoretical analysis and simulation experiments, it is proved that the community medical data can be effectively protected. [ABSTRACT FROM AUTHOR]

Previous studies on the fate of engineered nanoparticles (ENPs) incorporated in paints mainly focused on the release of the particles as affected by a limited number of factors or monitoring their release from natural sources. In this study, the effects of four factors (i.e., weathering duration, water pH, rainfall duration and intensity) were investigated on the release of SiO-ENPs, Ag-ENPs, and TiO-ENPs from paints applied on panels. The static water immersion test showed that the concentrations of studied particles all increased with weathering duration. At low and high pH, SiO-ENPs and Ag-ENPs showed a higher release, while the release of TiO-ENPs was relatively high at low pH. With increased simulated rainfall duration, the concentration released decreased for Si, and the opposite was observed for Ag, while no obvious correlation was noted for Ti. With greater rainfall intensity, there was increasing release of all particles. In total, the releases of Ag-ENPs and TiO-ENPs were extremely low and within the level of 21.32-42.16 μg Land 0.6-2.3 μg L, respectively, while the values for SiO-ENPs were in the range of 7.5-12 mg L. Additionally, microscopic results highlighted that SiO-ENPs were mainly released in the form of agglomerates, and only a small fraction was below 0.1 μm. Considering these influence factors together, conclusions may be made that weathering time and rainfall duration are more important in controlling release than water pH. [ABSTRACT FROM AUTHOR]

One-dimensional ternary nanostructures, AgCO nanorod cores coated with an intermediate layer of Ag nanoparticles (NPs) and a sheath of conducting polymer polyaniline (PANI), AgCO/Ag/PANI composite nanorods (CNRs), were successfully prepared via a facile two-step method. Ag NPs were first uniformly anchored onto the AgCO nanorods to form binary AgCO/Ag CNRs with an in situ visible-light-induced reduction strategy, and then the AgCO/Ag CNRs were coated with PANI of different contents through a simple chemisorption approach. The as-obtained hybrids exhibit significantly enhanced photoelectrochemical current response and photoactivity in degrading methyl orange under visible-light illumination ( λ > 420 nm). The improved photoactivity was found to be related to the intermediate Ag between AgCO and PANI which facilitates the separation efficiency of photogenerated carriers, and an optimal weight percent of 2.0% PANI was observed. The origin of enhanced photoactivity was further investigated by a radical-trapping test, and a Z-scheme mechanism was proposed to explain the charge separation behaviors. [ABSTRACT FROM AUTHOR]

Reversible logic, as an interesting and important issue, has been widely used in designing combinational and sequential circuits for low-power and high-speed computation. Though a significant number of works have been done on reversible combinational logic, the realization of reversible sequential circuit is still at premature stage. Reversible counter is not only an important part of the sequential circuit but also an essential part of the quantum circuit system. In this paper, we designed two kinds of novel reversible counters. In order to construct counter, the innovative reversible T Flip-flop Gate (TFG), T Flip-flop block (T_FF) and JK flip-flop block (JK_FF) are proposed. Based on the above blocks and some existing reversible gates, the 4-bit binary-coded decimal (BCD) counter and controlled Up/Down synchronous counter are designed. With the help of Verilog hardware description language (Verilog HDL), these counters above have been modeled and confirmed. According to the simulation results, our circuits' logic structures are validated. Compared to the existing ones in terms of quantum cost (QC), delay (DL) and garbage outputs (GBO), it can be concluded that our designs perform better than the others. There is no doubt that they can be used as a kind of important storage components to be applied in future low-power computing systems. [ABSTRACT FROM AUTHOR]

The emerging memristor-based neuromorphic engineering promises an efficient computing paradigm. However, the lack of both internal dynamics in the previous feedforward memristive networks and efficient learning algorithms in recurrent networks, fundamentally limits the learning ability of existing systems. In this work, we propose a framework to support complex learning functions by introducing dedicated learning algorithms to a bio-plausible recurrent memristive network with internal dynamics. We fabricate iron oxide memristor-based synapses, with well controllable plasticity and a wide dynamic range of excitatory/inhibitory connection weights, to build the network. To adaptively modify the synaptic weights, the comprehensive recursive least-squares (RLS) learning algorithm is introduced. Based on the proposed framework, the learning of various timing patterns and a complex spatiotemporal pattern of human motor is demonstrated. This work paves a new way to explore the brain-inspired complex learning in neuromorphic systems. [ABSTRACT FROM AUTHOR]