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To account for the nonlinear dynamic effects of flexible sandwich plates undergoing large deformation, a computational method for dynamic analysis of flexible sandwich plates is studied. According to the characteristics of sandwich plates, a simplified plate model is proposed based on the Kirchhoff plate theory, in which the shear stiffness of the core plate is neglected and the stiffness for the whole plate is derived. For the dynamic problem of flexible multibody systems, a thin plate element has been studied based on the absolute nodal coordinate formulation (ANCF). Meanwhile, a method based on invariant tensors is proposed for calculating elastic forces and their Jacobians, which can be calculated during preprocessing and applied for programmed calculation. Using examples, the proposed computational method is verified to be feasible and accurate. In addition, a benchmark example and a double-pendulum model are used to verify the applicability and feasibility of our analytical method for flexible sandwich plates in flexible multibody systems. Therefore, this method lays a foundation for the study of flexible dynamics problems regarding multibody systems with sandwich plates. [ABSTRACT FROM AUTHOR]

Cancer treatment by inducing tumor cell immunogenic cell death (ICD) is critical for tumor therapy. However, ICD activation by single pathway is often limited in practical application due to its low efficiency. In addition, the low pH and anoxic microenvironments in solid tumors greatly limit the effective activation of ICD. Herein, hollow manganese dioxide (H-MnO2) nanomaterials were selected to load both Mitoxantrone (MTZ) and Chlorin e6 (Ce6) due to its hollow structure and ability to release drugs in the acidic environments. Thus, the synergy of photodynamic therapy (PDT), photothermal therapy (PTT) and chemotherapy can induce the process of immunogenic cell death, stimulate the maturation of dendritic cells (DCs), and activate the immune response to kill tumor cells dramatically. Efficient immunotherapeutic effects were obtained when MnO2-C/M-HA was given intravenously to 4T1 tumor-bearing BALB/c mice with 660 nm near-infrared laser irradiation. This study overcame the limitations of monotherapy and provided a multifunctional platform for tumor immunotherapy. [ABSTRACT FROM AUTHOR]

A photoelectrochemical (PEC) biosensor based on a multiple signal amplification strategy was established for highly sensitive detection of microRNA (miRNA). TiO2 was prepared on the surface of titanium sheet by laser etching to improve its stability and photoelectrical properties, and CuInS2-sensitized TiO2 was used to form a superior photoelectrical layer, which realized the initial signal amplification. The electron donor dopamine (DA) was modified to H2 as a signal regulator, which effectively increased the photocurrent signal. To further amplify the signal, an enzyme-free hybridization reaction was implemented. When target let-7a and fuel-DNA (F-DNA) were present, the base of H1 specifically recognized let-7a and forced dopamine@AuNPs-H2 away from the electrode surface. Subsequently, the end base of H1 specifically recognized F-DNA, and let-7a was replaced and recycled to participate in the next cycle. Enzyme-free circulation, as a multifunctional amplification method, ensured the recycling of target molecules. This PEC sensor for let-7a detection showed an excellent linear response from 0.5 to 1000 pM with a detection limit of 0.12 pM. The intra-batch RSD was 3.8% and the recovery was 87.74–108.1%. The sensor was further used for clinical biomolecular monitoring of miRNA, showing excellent quantitative detection capability. [ABSTRACT FROM AUTHOR]

Highlights: The Internet of Things era related electronics were updated based on carbon nanotube transistors, radiofrequency circuits and energy storage devices. The applications in healthcare and biomedical devices were discussed including sensory, data processors and actuators. The fabrication of wafer-scale carbon nanotubes has been introduced as well as the machine learning strategy for prediction of optimal synthesis parameters.The post-Moore's era has boosted the progress in carbon nanotube-based transistors. Indeed, the 5G communication and cloud computing stimulate the research in applications of carbon nanotubes in electronic devices. In this perspective, we deliver the readers with the latest trends in carbon nanotube research, including high-frequency transistors, biomedical sensors and actuators, brain–machine interfaces, and flexible logic devices and energy storages. Future opportunities are given for calling on scientists and engineers into the emerging topics. [ABSTRACT FROM AUTHOR]

Highlights: The structure–property relationship of PdSe2 is discussed, i.e., layer number vs. tunable bandgap, pentagonal structure vs. anisotropy-based polarized light detection. The synthesis approaches of PdSe2 are thoroughly compared, including bottom-up methods such as chemical vapor transport for bulk crystals, chemical vapor deposition for thin films and single-crystal domains, selenization of Pd films. Besides, top-down strategies are discussed, covering the mechanical exfoliation of bulk crystals, plasma thinning, and vacuum annealing as well as phase transition. The emerging devices of PdSe2 and its van der Waals heterostructures have been delivered such as metal/semiconductor contact, Schottky junction transistors, field-effect transistors, photodetectors, p–n junction-based rectifiers, polarized light detector, and infrared image sensors. Future opportunities of PdSe2-based van der Waals heterostructures are given including logic gate-based digital circuits, RF-integrated circuits, Internet of Things, and theoretical calculation as well as big data for materials science.The rapid development of two-dimensional (2D) transition-metal dichalcogenides has been possible owing to their special structures and remarkable properties. In particular, palladium diselenide (PdSe2) with a novel pentagonal structure and unique physical characteristics have recently attracted extensive research interest. Consequently, tremendous research progress has been achieved regarding the physics, chemistry, and electronics of PdSe2. Accordingly, in this review, we recapitulate and summarize the most recent research on PdSe2, including its structure, properties, synthesis, and applications. First, a mechanical exfoliation method to obtain PdSe2 nanosheets is introduced, and large-area synthesis strategies are explained with respect to chemical vapor deposition and metal selenization. Next, the electronic and optoelectronic properties of PdSe2 and related heterostructures, such as field-effect transistors, photodetectors, sensors, and thermoelectric devices, are discussed. Subsequently, the integration of systems into infrared image sensors on the basis of PdSe2 van der Waals heterostructures is explored. Finally, future opportunities are highlighted to serve as a general guide for physicists, chemists, materials scientists, and engineers. Therefore, this comprehensive review may shed light on the research conducted by the 2D material community. [ABSTRACT FROM AUTHOR]

Highlights: The current understanding and advances on laser synthesis of nanomaterials are summarized. The laser microfabrication-enabled energy conversion and storage devices are reviewed. The limitations and solutions for current laser processing of nanomaterials and other more potential development directions for laser processing are proposed.Nanomaterials are known to exhibit a number of interesting physical and chemical properties for various applications, including energy conversion and storage, nanoscale electronics, sensors and actuators, photonics devices and even for biomedical purposes. In the past decade, laser as a synthetic technique and laser as a microfabrication technique facilitated nanomaterial preparation and nanostructure construction, including the laser processing-induced carbon and non-carbon nanomaterials, hierarchical structure construction, patterning, heteroatom doping, sputtering etching, and so on. The laser-induced nanomaterials and nanostructures have extended broad applications in electronic devices, such as light–thermal conversion, batteries, supercapacitors, sensor devices, actuators and electrocatalytic electrodes. Here, the recent developments in the laser synthesis of carbon-based and non-carbon-based nanomaterials are comprehensively summarized. An extensive overview on laser-enabled electronic devices for various applications is depicted. With the rapid progress made in the research on nanomaterial preparation through laser synthesis and laser microfabrication technologies, laser synthesis and microfabrication toward energy conversion and storage will undergo fast development. [ABSTRACT FROM AUTHOR]

Each type of asteroids and comets are important, serving as the unique puzzle pieces of the solar system. The countless number of small bodies spread vastly from the near-Earth orbits to the main belt and beyond Jupiter. Thus, in order to complete the whole puzzle, and hence requires a well-designed roadmap of sample return (SR) missions and international coordination. The main consideration is the accreting locations of various types of asteroids, which may be referred through their redox status and abundances of water and volatile components. C-complex asteroids are water and volatile-rich, likely accreted in the outer solar system. Two C-complex asteroids are being explored by Hayabusa-2 and OSIRIS-REx missions, respectively. In contrast, enstatite chondrite-like asteroids formed under extremely reducing conditions in the inner solar system. The samples returned from enstatite chondrite-like asteroids will clarify the nebular processes in the zone closest to the Sun, and reveal fractionation of the solar nebula along the radial direction, via comparing with those of the C-complex asteroids. The exploration will also shed light on the bulk compositions of the Earth and terrestrial planets accreted in the same region of the inner solar system. The SR missions will focus on the first 10 Ma history of the solar system, including the initial condition, the nebular processes, and the accretion of planetesimals. Because the secondary processes that took place in planetesimals, such as thermal metamorphism, aqueous alteration, melting and differentiation, could largely erase the records of the nebular events, it is critically important to choose the primordial asteroid targets. Although C-complex asteroids accreted at low temperature in the outer solar nebula, they, especially those hydrated, could have suffered severe aqueous alteration as observed in CM chondrites. Other preferred targets are L-type asteroids, which probably contain abundant Ca-, Al-rich inclusions, the first solid assemblages of the solar system. Based on the roadmap of SR missions, we propose to return samples first from enstatite chondrite-like or L-type Near-Earth asteroids. [ABSTRACT FROM AUTHOR]

Highlights: Bifunctional electrode and electrolytic cell configuration for electrochemical water splitting are reviewed. The different green energy systems powered water splitting are summarized and discussed. An outlook of future research prospects for the development of green energy system powered water splitting in practical application process is proposed.Hydrogen (H2) production is a latent feasibility of renewable clean energy. The industrial H2 production is obtained from reforming of natural gas, which consumes a large amount of nonrenewable energy and simultaneously produces greenhouse gas carbon dioxide. Electrochemical water splitting is a promising approach for the H2 production, which is sustainable and pollution-free. Therefore, developing efficient and economic technologies for electrochemical water splitting has been an important goal for researchers around the world. The utilization of green energy systems to reduce overall energy consumption is more important for H2 production. Harvesting and converting energy from the environment by different green energy systems for water splitting can efficiently decrease the external power consumption. A variety of green energy systems for efficient producing H2, such as two-electrode electrolysis of water, water splitting driven by photoelectrode devices, solar cells, thermoelectric devices, triboelectric nanogenerator, pyroelectric device or electrochemical water–gas shift device, have been developed recently. In this review, some notable progress made in the different green energy cells for water splitting is discussed in detail. We hoped this review can guide people to pay more attention to the development of green energy system to generate pollution-free H2 energy, which will realize the whole process of H2 production with low cost, pollution-free and energy sustainability conversion. [ABSTRACT FROM AUTHOR]

An increasing number of robotic systems involving lots of robotic individuals are used to serve human, such as intelligent terminal, intelligent storage, intelligence factories, etc. It is a trend of robotics technology that robotics system will become huger with more individuals. In these systems, they form the robotic societies and need establish some computing rules and mechanisms to ensure the operation like all biological social systems. In this paper, a novel system architecture for swarm robotic system, including three layers: human-computer interaction layer, planning layer and execution layer, is put forward, which is effective for task-oriented swarm robotic system. Then, a hierarchical organizational model for the system is presented, which is used to establish management relationship between different layers and individuals. Because task-oriented characteristic is required, this paper elaborates task description knowledge to explain the relationship between tasks for task decomposition and task logic. In addition, a method of behavior generation based on proposition/transition Petri networks is designed, which would effectively assist the system to construct combined behavior using simple individual behavior to solve a variety of tasks. At last, Illustration is shown to prove effectiveness and an implementation of the method based on SociBuilder system is introduced. [ABSTRACT FROM AUTHOR]

Highlights: Bifunctional electrode and electrolytic cell configuration for electrochemical water splitting are reviewed. The different green energy systems powered water splitting are summarized and discussed. An outlook of future research prospects for the development of green energy system powered water splitting in practical application process is proposed. Hydrogen (H2) production is a latent feasibility of renewable clean energy. The industrial H2 production is obtained from reforming of natural gas, which consumes a large amount of nonrenewable energy and simultaneously produces greenhouse gas carbon dioxide. Electrochemical water splitting is a promising approach for the H2 production, which is sustainable and pollution-free. Therefore, developing efficient and economic technologies for electrochemical water splitting has been an important goal for researchers around the world. The utilization of green energy systems to reduce overall energy consumption is more important for H2 production. Harvesting and converting energy from the environment by different green energy systems for water splitting can efficiently decrease the external power consumption. A variety of green energy systems for efficient producing H2, such as two-electrode electrolysis of water, water splitting driven by photoelectrode devices, solar cells, thermoelectric devices, triboelectric nanogenerator, pyroelectric device or electrochemical water–gas shift device, have been developed recently. In this review, some notable progress made in the different green energy cells for water splitting is discussed in detail. We hoped this review can guide people to pay more attention to the development of green energy system to generate pollution-free H2 energy, which will realize the whole process of H2 production with low cost, pollution-free and energy sustainability conversion. [ABSTRACT FROM AUTHOR]