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Rechargeable aqueous zinc-ion batteries (AZIBs) that directly use metallic zinc as anode and mildly acidic Zn2+-containing aqueous solutions as electrolytes have exhibited promising complementarity for well-established lithium-ion batteries. The fabrication of high-voltage, high-capacity, and durable cathode and stable anode are the burning issues of fabricating high-performance AZIBs. Herein, the small amount of dual-cation preintercalated and amorphous carbon confined vanadium dioxide (Ni0.006Ca0.0045VO2@C) was prepared for high-performance Zn2+-storage materials, and subsequent in situ electrochemical anodic oxidation strategy was used to convert Ni0.006Ca0.0045VO2@C to δ-(Ni,Ca)V2O5@C as high-capacity AZIB cathode. The elaborate architecture not only showed a high specific capacity of 433.8 mAh g−1 at 0.1 A g−1 but also retained a reversible capacity of 74 mAh g−1 after 4000 cycles at 5 A g−1. In addition, the Zn2+/H+ co-intercalation mechanism was also verified by employing ex situ XRD and ex situ XPS. Finally, the flexible quasi-solid-state ZIBs were also assembled with the Ni0.006Ca0.0045VO2@C as cathode and polyvinyl alcohol hydrogel as electrolyte, suggesting its promising application for the superior Zn2+-storage performance.

The design and preparation of electrode materials are of great significance for improving the overall performance of energy storage devices. Zeolitic imidazolate frameworks (ZIFs) and their derivatives have attracted significant attention as they provide a library of new energy storage materials. ZIFs act as the perfect precursor due to their high porosity, controllable crystal structures, and tunable chemical compositions. The high structural tunability endows ZIFs and ZIFs-derivatives with broad application prospects in various energy storage devices. In this review, we discussed the crystal structures and preparation methods of ZIFs and focused on the application progress of ZIFs and ZIFs-derivatives in supercapacitors and batteries. Furthermore, we summarized the current challenges and provided perspectives about ZIFs and their derivatives for future electrode materials, aiming to fully understand this field and promote the widespread use of ZIF-based composites and ZIF-derived materials in the field of energy storage.

Unique two-dimensional (2D) porous nanosheets with overwhelmingly rich channels and large specific surface area exhibit superior electrochemical capacitance performance, as compared to the conventional zero- and one-dimensional counterparts. As ternary transition metal sulfides (TMSs) are well recognized for their high electrochemical activity and capacity, and the replacement of oxygen with sulfur may result in high stability and flexible properties of the nanomaterials, as compared to transition metal oxides, herein we report the synthesis of 2D porous nanosheet arrays of ZnxCo1-xS (x = 0, 0.25, 0.5, 0.75, and 1) via a facile hydrothermal process. Due to the synergistic effect of the metal components and a unique 2D porous structure, the Zn0.5Co0.5S electrode was found to stand out as the best among the series, with a high specific capacity of 614 C g−1 at 1 A g−1 and excellent cycle retention rate of 90 % over 10, 000 cycles at 10 A g−1. Notably, a supercapattery based on a Zn0.5Co0.5S positive electrode and an activated carbon (AC) negative electrode (Zn0.5Co0.5S//AC) was found to display a 1.6 V voltage window, a 61 mA h g−1 specific capacity at 1 A g−1, a 49 Wh kg–1 energy density at 957 W kg–1 power density, and excellent cycling performance (88 % over 10, 000 cycles), suggesting tremendous potential of Zn0.5Co0.5S in the development of high-performance supercapattery devices.

Metal phosphates, such as LiFePO4 (LFP), have been attracting extensive attention as electrode materials for next-generation rechargeable metal-ion batteries (MIBs), due to their high theoretical capacity, good chemical stability, long lifespan, and natural abundance. In this review, the recent progress of the design and engineering of metal phosphate-based electrode materials for MIBs is summarized. Specifically, the survey will focus on three types of phosphates, monometallic phosphates, bimetallic phosphates, and multi-metal phosphates, within the context of their intrinsic structure and corresponding electrochemical performance. A range of experimental variables will be carefully analyzed, such as sample synthesis, crystal structure, and electrochemical reaction mechanism, in conjunction with theoretical calculations. The applications of these materials as MIB electrodes are then featured for diverse MIBs, such as lithium-ion battery, sodium-ion batteries, potassium-ion batteries, calcium-ion batteries, and magnesium-ion batteries. We conclude the review with a perspective where the promises and challenges of phosphate-based electrodes for MIBs are highlighted, along with future research directions.

Typical layered structures with large capacity have attracted much interest in lithium ion batteries and emerging post-lithium ion batteries. However, these typical layered oxides, including α-, δ-V2O5, δ-MnO2, and α-MoO3, have suffered poor electrical conductivity, severe structural deterioration, and sluggish diffusion kinetics during the repetitive charging/discharging process. In recent years, interlayer engineering of preintercalation strategies has offered effective solutions for solving these problems. Structural water molecules (H2O), monovalent alkali cations (Li+/Na+/K+) and ammonium ion ( NH 4 + ), multivalent alkali-earth cations (Mg2+/Ca2+/Ba2+) and aluminum ion (Al3+), various transition metal cations (Mn2+/Fe2+/Co2+/Ni2+/Cu2+/Zn2+/Ag+, etc.), and organic molecules (PANI/PEDOT/PEO, etc.) have been proved to be efficient “pillars” for stabilizing the fragile layered structure and enhanced diffusion kinetics. These prominent effects have boosted the developments of preintercalated layered structures for emerging multivalent metal-ion batteries, especially rechargeable aqueous zinc ion batteries (AZIBs). In this review, we have clarified the representative crystal structures, preparation methods, advanced characterization methods and corresponding mechanistic insights, and successful applications of these preintercalated layered oxides in multivalent metal-ion batteries.

Summary 5G has taken off at a brisk speed over the years, bringing significant benefits to the Internet of Things (IoT) devices and wireless sensor nodes. The launching of 5G technology provides an excellent opportunity for the faster development of smart cities. Nanogenerators (NGs) have been widely demonstrated as sustainable power sources and self-powered active sensors. The last 15 years of research on NGs have revealed that it can contribute to the digitalization of smart city services, such as localized renewable energy supplies, intelligent transportation, smart vehicles, and digital healthcare applications. The integration of novel NG technology in smart cities will solve problems pertinent to sustainable power sources for decentralized IoT devices and provide pathways for realizing self-powered active sensing systems. In this review, we will provide a comprehensive review of current research on NGs’ applications in different sectors of a smart city. More importantly, we will show how NGs can be a game changer in the development of smart cities under 5G services and how the usage of NGs can boost the convenience of city dwellers. Our aim is to draw more attention to NG applications in the digitalization of smart cities and provide a guideline for applying smart concepts in future urban planning.

A conformal, stretchable, and integrated epidermal patch is developed to simultaneously monitor biophysical and biochemical signals via an all-in-one design. Ultrasonic transducers are used to monitor cardiovascular status of blood pressure and heart rate from the carotid artery, and electrochemical sensors are used to detect biomarker levels of lactate, caffeine, and alcohol from sweat and glucose from interstitial fluid. The counteracting and synergistic effects of exercise, alcohol intake, food intake, and caffeine intake on cardiovascular parameters, and the continuous and dynamic physiological monitoring are also experimentally validated.

A high-performance liquid chromatography (HPLC) method has been developed for the determination of related substances in egg yolk lecithin. Chromatographic separation was achieved using a gradient elution on a Waters Xbridge HILIC column maintained at 35 ℃. Mobile phase A was composed of water-acetonitrile (80:20, v/v, containing 5 mM ammonium acetate), and mobile phase B was composed of acetonitrile. Analytes were monitored by a charged aerosol detector (CAD) at 50 ℃. The novel HPLC-CAD method was selective and sensitive for the determination of related substances in egg yolk lecithin in its commercial bulk batches. It was also successfully validated by the International Council for Harmonisation (ICH) guidelines. The method will be a renewal of an old Chinese Pharmacopoeia method (2020 edition). Moreover, quadrupole time-of-flight mass spectrometry (Q-TOF-MS) was integrated with HPLC to investigate phospholipid species in egg yolk lecithin. This work provides comprehensive composition profiles of egg yolk lecithin, thereby accelerating the quality control, development, and application of egg yolk lecithin.

Polyethylene (PE) textiles can be engineered through structural optimization for efficient wicking and drying to simultaneously offer radiative and evaporative cooling. The great advantages of smart PE textiles beyond conventional textiles in energy savings, water conservation and low environmental footprint are systematically investigated to drive sustainable energy and environmental development of the textile industry.

Silica aerogels are prone to be destroyed due to their brittleness and low mechanical properties, which limits their applications. To break the unfavorable situation, we presented a scalable and facile approach to assemble blocky silica-reduced graphene oxide (SiO2-rGO) hybrid sponges by atmospheric pressure drying technique. Briefly, ungelled silica solution from two-step sol-gel of tetraethoxysilane (TEOS), was incorporated into compressible graphene sponge (CGS). Different silicon concentration ratios had great influence on the performance of hybrid sponges. When VTEOS: Vethanol was fixed at 1:15, the sample had good flexibility and could absorb 8.5–10.2 times its own mass of solvents, but the adsorption efficiency slightly decreased with the increase of the number of experiments. When VTEOS: Vethanol was fixed at 4:7, the SiO2-rGO hybrid sponges exhibited unbroken shape, low volume shrinkage (24%), large specific surface area (803.351 m2/g), and high mass retention (83.64%) at 790 °C of thermal treatment. Moreover, they could support approximately 146 times their weight without structural damage, and possess excellent hydrophobicity with 129 ± 1° of water contact angle. These superior properties enable SiO2-rGO hybrid sponges to exhibit highly efficient absorption of oils and toxic solvents, to be regenerated (10 times) with the full release of adsorbates by heat treatment.

Aluminum is known as the most ubiquitous metal in earth's crust but its excessive exposure will cause damage to environment and health of the organism. Here, a turn-on Schiff base fluorescence probe STH based on excited state intramolecular proton transfer and photoelectron transfer processes for Al3+ detection with fast response rate (within minutes), low detection limit (4.26×10-8M), high selectivity and reasonable pH application range (5.0-8.0) was developed. Fluorescence titration experiments show that probe STH has an excellent linear relationship (R2=0.9694) with Al3+ concentration and could be applied to quantitatively recognize Al3+ in real-water samples. Based on Job's plot and in situ mass spectra, two STH molecules will complex with Al3+ to form 2:1 complexation with oxygen atoms of hydroxyl and carbonyl groups and nitrogen atom of CN bond participating in coordination.

Forthcoming wearable and portable electronics such as Google Glass and smart cloths urgently require the development of foldable Li-ion batteries (LIBs) to fit diverse shapes, operate under repeated folding motions, and facilitate collapsible designs. Here we report for the first time a hydrothermal reduction synthesis of a very thin (5-μm-thick) Ni film with inverted pyramids (NFIP); the resultant film exhibits an extremely high conductivity of 1.25 × 105 S cm-1. This inverted pyramid design enables the realization of an NFIP whose resistance deviates by 0.19% and 0.72% from its initial value after 22,000 (outward) and 18,000 (inward) folding cycles. The foldable LIB show a capacity retention of 98.4% at 20 C after being subjected to 5000 cycles of full folding (180°) compared to that delivered under the initial flat state. We also demonstrate a foldable LIB integrated with a Google Glass model in which the battery powers an LED lamp during 9000 cycles of folding (90°) motions.

Varieties of nanostructured SnO2 have been widely investigated as promising anode material for next generation lithium-ion batteries (LIBs). However, traditional nanostructures suffer from re-agglomeration and excessive side reactions, which lead to low coulombic efficiency, poor rate performance and dramatic capacity decay. Here we develop an easy and robust strategy to fabricate carbon framework microbelts anchoring ultrafine SnO2 nanoparticles (U-SnO2 NPs@ CF-MBs), which takes advantage of the synergistic effect between high conductivity of large-size carbon framework and high activity of ultrafine SnO2 nanoparticles. The as-fabricated U-SnO2 NPs@C-BsF composite deliver high capacity of 925 mAh g−1 after 250 cycles at current density of 200 mA g−1, high rate capacity of 464 mAh g−1 at a high current density of 5000 mA g−1 and long cycle performance of 788 mAh g−1 after 1000 cycles at current density of 1500 mA g−1 in half cells. When applied in a full cell by coupling with a LiCoO2 cathode, the fabricated U-SnO2 NPs@ CF-MBs composite full cells keep a high capacity of 510 mAh g−1 after 80 cycles. Notably, the electrode exhibit two platforms located at 3.3 and 2.6 V, which indicate that the conversion between SnO2 and Sn is also highly reversible in full cells. The excellent lithium storage of large-scale U-SnO2 NPs@ CF-MBs ensures its great promise for commercial utilization in the future LIBs.

A novel coumarin chalcone derivative 1 was designed, synthesized and characterized by nuclear magnetic resonance spectra and high resolution mass spectrum. The photophysical and recognition properties of the compound as red fluorescent probe for cyanide and biothiols including cysteine (Cys), homocysteine (Hcy) and glutathione (GSH) have been discussed systematically. Red fluorescence probe 1 was able to achieve rapid and selective identification for cyanide anion and biothiols in aqueous solutions with red fluorescence quench. In addition, the recognition mechanism of 1 was demonstrated by in situ 1H NMR. The compound has two potential nucleophilic sensing sites including carbon-carbon double bond and 4-position of coumarin. The results indicate that cyanide anions can be bonded to these two sites to afford 2:1 bonding product. But biothiols only are bonded to carbon-carbon double bond by Michael addition reaction. The bonding of both cyanide and biothiols to the probe disrupts intramolecular charge transfer and leads to fluorescence quench.

A pyridine inner salt compound 2-{2-[7-(N, N-diethylamino)coumarin]vinyl}-N-(3-sulfonatepropyl)-pyridinium, inner salt (1) with strong red fluorescence emission and good water solubility was synthesized by condensation reaction between 7-diethylaminocoumarin-3-aldehyde and 2-methyl-N-(3-sulfooxypropyl)pyridinium, inner salt. Investigation on UV–vis absorption, fluorescence properties and cyanide recognition of the compound indicates that this compound can specifically recognize cyanide in aqueous solution with detection limit being 0.0003 μM. The color of compound solution exhibits change from brick red to purple accompanied by red fluorescence decrease, which can realize naked eye observation. Based on in situ 1H NMR, mass spectra and Job’s plot, 4-coumarin is more likely to react with cyanide anions by nucleophilic substitution.

Circular RNAs (circRNAs) are key regulators in the development of many cancers. The present study was aimed to investigate the mechanism by which circ_0007919 affected colorectal cancer (CRC) progression.The differentially expressed circRNA was screened out by analyzing the expression profile of circRNAs of CRC tissues. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed for detecting the expressions of circ_0007919, miR-942-5p, and ten-eleven translocation 1 (TET1) mRNA in CRC tissues and cell lines. Cell growth and migration were assessed by cell counting kit-8 (CCK-8) 5-bromo-2'-deoxyuridine (BrdU) and scratch assays. Bioinformatics analysis and dual-luciferase reporter assay were conducted to predict and validate the targeted relationships between circ_0007919 and miR-942-5p, as well as between miR-942-5p and TET1 mRNA. Besides, Western blot was conducted for detecting TET1 protein expression in CRC cells. It was revealed that, in CRC tissues and cell lines, circ_0007919 and TET1 expressions were reduced whereas miR-942-5p expression was enhanced. It was also revealed that circ_0007919 overexpression markedly suppressed CRC cell growth and migration. In addition, circ_0007919 could competitively bind with miR-942-5p to increase the expression of miR-942-5p's target gene TET1. Collectively, circ_0007919 inhibits CRC cell growth and migration via regulating the miR-942-5p/TET1 axis. This study helps to better understand the molecular mechanism of CRC progression.

The efficient conversion of ultrasound into electrical energy remains a highly desirable wireless powering solution, with potentially profound ramifications in energy transfer across virtually all industrial fields, especially for implantable medical devices. Triboelectric nanogenerators have been shown to effectively carry out ultrasound energy transduction, though efficiency remains poor. Here, we devise a computational model to investigate the optimal triboelectric nanogenerator irradiation conditions, including frequency, probe distance, size, and design, as represented by irradiated triboelectric surface area displacement. Our investigation may set the foundations for the establishment of a standardized protocol for efficient ultrasound mechanical energy harvesting. This holds considerable significance and could be paramount in designing an ever-growing number of applicative solutions in wireless energy transfer, providing a scalable, cost effective and time saving solution in the development of implantable medical devices.

Nanotechnology has been widely used for developing sensors with higher sensitivity and better selectivity. In this study, a molecularly imprinted electrochemical sensor based on nitrogen-doped carbon nanosheet frameworks decorated with Fe (Fe-NCNF) was proposed for simultaneous detection of mebendazole (Meb) and catechol (CC). Fe-NCNF was prepared by chemical blowing, and it was coated with molecularly imprinted polymer (MIP) to construct a novel hybrid nanomaterial, which is named Fe-NCNF/MIP. Meb-MIP was electropolymerized with methacrylic acid (MAA) as monomer via cyclic voltammetry (CV) method. This sensor architecture can detect Meb because of the high binding affinity of MIP. With the large specific surface area, Fe-NCNF can adsorb and electrochemically oxidize CC. The good selectivity of Fe-NCNF/MIP for CC and Meb was proven by anti-interference test, for which the oxidation potentials were set at 0.15 and 0.82 V respectively. The linear range for determination of CC was from 0.5 to 25 μM with a low limit of detection (LOD) of 0.06 μM (S/N = 3), and that for Meb was 0.01–1.5 μM with a low LOD of 0.004 μM (S/N = 3). Furthermore, this MIP electrochemical sensor was applied for the simultaneous detection of CC and Meb in tap water and river water. These results demonstrated that this method is reliable for selective, sensitive and feasible determination of Meb and CC.

In this paper, a novel molecularly imprinted electrochemical sensor (MIECS) based on a glassy carbon electrode (GCE) modified with graphene quantum dots (GQDs) coated on hollow nickel nanospheres (hNiNS) for the rapid determination of bisphenol S (BPS) was proposed for the first time. HNiNS and GQDs as electrode modifications were used to enlarge the active area and electron-transport ability for amplifying the sensor signal, while molecularly imprinted polymer (MIP) film was electropolymerized by using pyrrole as monomer and BPS as template to detect BPS via cyclic voltammetry (CV). Scanning electron microscope (SEM), energy-dispersive spectrometry (EDS), CV and differential pulse voltammetry (DPV) were employed to characterize the fabricated sensor. Experimental conditions, such as molar ratio of monomer to template, electropolymerization cycles, pH, incubation time and elution time were optimized. The DPV response of the MIECS to BPS was obtained in the linear range from 0.1 to 50μM with a low limit of detection (LOD) of 0.03μM (S/N = 3) under the optimized conditions. The MIECS exhibited excellent response towards BPS with high sensitivity, selectivity, good reproducibility, and stability. In addition, the proposed MIECS was also successfully applied for the determination of BPS in the plastic samples with simple sample pretreatment.

A key challenge in the development of electrochemical energy storage (EES) is the design and engineering of electrode materials for electrochemical reactions. Transition metal oxalates (TMOxs) have been widely used in various EES applications due to their low cost, simple synthesis, and excellent electrochemical performance. In this review, the recent advances in the design and engineering of transition metal oxalate-based micro- and nanomaterials for EES are summarized. Specifically, the survey will focus on three types of micro- and nano-scale TMOxs (monometallic, bimetallic, and trimetallic TMOxs), their composites (TMOx-metal oxide, TMOx-hydroxide, TMOx-GO, and TMOx-MOFs composites), and derivatives, including transition metal oxides (TiO2, V2O5, MnxOy, Co3O4, NiO, CuO, and Nb2O5), multi-transition metal oxides (MCo2O4 (M = Ni, Cu, and Zn), NiMn2O4, and NxOy-MxOy), transition metal sulfide (NiS2), and carbon materials (ordinary carbon, GO and their composites), within the context of their intrinsic structure and corresponding electrochemical performance. A range of experimental variables will be carefully analyzed, such as sample synthesis, crystal structure, and electrochemical reaction mechanism. The applications of these materials as EES electrodes are then featured for supercapacitors (SCs) and lithium-ion batteries (LIBs). We conclude the review with a perspective of future research prospects and challenges.

A novel Iridium (III) complex [Ir(ppy) 2 (Hppip)]PF 6 ( 1 ) has been synthesized and characterized. The complex exhibits strong phosphorescence emission in high viscosity solvent glycerol and aggregation-induced phosphorescence emission in hexane solution. The high viscosity of glycerol and aggregation may restrict intramolecular rotation so that the compound exhibits stronger phosphorescence emission in glycerol and aggregated state. Compound 1 can also be a pH chemosensor to monitor pH changes in PBS buffer solution because of two successive protonation processes of pyridyl and imidazole moieties in acidic condition.

Doping polymers with ceramic nanofillers is a widely-adopted routine for developing high-performance nanocomposites. However, improving the interaction between the nanofillers and the polymer matrix for an enhanced composite performance remains highly desired in the community. Herein, we systematically investigated the barium titanate doped polyvinylidene fluoride (BTO/PVDF) piezoelectric nanocomposites in a fiber form through comprehensive phase-field simulation and detailed experimental characterization. Both experimental and theoretical results indicated that the introduction of 2.15 vol% polydopamine (PDA) coating on the BTO nanoparticles could remarkably promote the local all-trans conformation and modulus match at the nanofillers-polymer interface, giving rise to the maximum piezoelectric charge coefficient and piezoelectric voltage coefficient as well as mechanical stiffness. To demonstrate the effectiveness of the PDA modification, a polydopamine modified nonwoven piezoelectric (PMNP) textile was constructed based on the composite fiber, which showed outstanding sensitivity and long-term stability for wearable biomonitoring, including limb motion detection, facial expression identification, respiratory monitoring, and human-machine interfacing. This work endows insight into the fundamental mechanism of the interfacial coupling effect in polymer composites for the development of high-performance wearable textile bioelectronics.

This paper proposes an integrated coupled map lattices (ICML) to assess the node states and study the vulnerability of weighted urban rail transit networks (URTNs) subjected to the external disturbance R. Meanwhile, the passenger flow is refined as the passenger in-flow and out-flow of the station, and a new passenger flow redistribution rule is proposed to discuss the cascading failures of URTNs. Moreover, three parameters are adopted to analyze the vulnerability characteristics of URTNs subjected to cascading failures and Nanjing metro network is taken as the example to verify the feasibility and effectiveness of the presented model. The results show that there is a linear relationship between the node betweenness and edge betweenness, and URTNs are very vulnerable subjected to malicious attacks and become more and more vulnerable with the increase of the external disturbance. Furthermore, we find that the largest degree node-based attack (LDA) is more likely to result in cascading failures and the highest betweenness node-based attack (HBA) can cause the most damage to URTNs subjected malicious attacks. We also discover that the external disturbance R=2 is the critical threshold to smash the Nanjing metro network subjected to the largest degree node-based attack, and R=2.3 is the critical threshold to crush Nanjing metro network subjected to the highest betweenness node-based attack and the largest strength node-based attack.

Improving the performance of advanced energy conversion and storage equipments has always been a key issue in energy research. In recent years, layered double hydroxides (LDHs), especially NiFe-LDHs, have been widely used in catalysts, photoactive materials, acid absorbers, supercapacitors and other fields because of their versatility and high efficiency. In addition, due to its unique layered structure and fascinating characteristics, two-dimensional (2D) NiFe-LDHs materials show excellent performance in various energy conversion and storage fields. This review concentrated on rationally designing of 2D NiFe-LDHs by various methods including co-precipitation method, hydrothermal treat, ion exchange, and electrodeposition method. We describe the morphology and interfacial design of 2D NiFe-LDHs and their composites, among which these 2D materials usually take on nanoscale shapes and they adopt shell-core structure, heterostructure, and others. After that this paper expounds advanced characterization technologies to analyse these materials. This review has summarized their electrochemical energy conversion and storage applications. Finally, the future challenges and prospects of 2D NiFe-LDHs materials in energy storage devices and other fields are summarized.

A diethylamino pyridine formyl Schiff base compound was synthesized via typical condensation reaction between 4- N , N -diethyl amino salicylic aldehyde and 2-pyridine formyl hydrazine in good yields. Its photophysical properties and selective recognition properties for biological thiols in aqueous solution have been investigated. The results indicate that the compound exhibits quickly obvious UV–vis absorption and fluorescence turn-off response to glutathione (GSH) based on intermolecular hydrogen-bond interaction in PBS butter solution. The copper complex of the compound shows quickly obvious turn-on fluorescence response to cysteine (Cys) based on replacement reaction with copper in PBS butter solution. Then the compound can selectively recognize three biological thiols of GSH, Cys and homocysteine (Hcy) in aqueous solution. The compound also can be successfully applied for bioimaging in living cell.

Pervasive and portable energy solutions are highly desired in the era of Internet of Things for powering wide-range distributed electronics. Human body contains renewable biomechanical energy sources, which could be harnessed for sustainable electricity generation as portable power sources for wearable bioelectronics. Herein, we propose an ultralow-cost, efficient, portable hand-driven triboelectric nanogenerator (HD-TENG) enabled by whirligig spinning to harvest energy from low-frequency and linear human biomechanical motions. Remarkably, the operating HD-TENG could easily achieve a rotational speed of over 10,000 rpm with a gentle hand stretching in a linear and periodic manner. The reported HD-TENG was demonstrated to charge a 220 μ F commercial capacitor up to 3 V in less than 80 s, and continuously drive a smart bracelet for health monitoring, and a portable MPEG-1 audio layer III for music playing. With a collection features of high output power, light weight, excellent portability, ease of transport, cost-effectiveness, and environmental friendliness, the ingeniously designed HD-TENG represents a convenient green power supply approach for wearable bioelectronics in the era of Internet of Things.

The segregation of asphalt pavement is the main reason for the decrease of safety, comfort and actual service life of the road, and the paving segregation is the main inducement for asphalt pavements segregation. Thus, a kind of effective paving segregation detection method can reduce the occurrence of asphalt pavement segregation. The traditional asphalt segregation detection methods are mainly divided into contact detection and non-contact detection. The contact detection method can only detect the segregation of pavement after paving or in use, and the non-contact detection method is also generally limited by the noise and expensive equipment. In recent years, the rapid development of image processing technology has provided a new research direction for asphalt paving segregation detection, but the accuracy and efficiency of the existing image-based asphalt paving segregation detection methods are insufficient. In order to solve these problems, this paper proposes an asphalt paving segregation detection method based on image texture features. Firstly, based on the traditional algorithms LBP (Local Binary Pattern) and GLCM (Gray-level Co-occurrence Matrix), a new texture feature extraction algorithm uniform pattern LBP-GLCM is proposed. Secondly, a detection method based on uniform pattern LBP-GLCM in combination with SVM (Support Vector Machine) is proposed. Then, the detection method proposed is validated using Kylbery texture dataset, the result show that this detection methods has great accuracy and efficiency in the classification of targets with similar texture features, it also means the texture feature extract method based on uniform pattern LBP-GLCM can combine the advantages of LBP and GLCM to achieve improvement of feature extraction's performance and efficiency. Finally, the detection method is applied to the diagnosis of asphalt paving segregation, and the accuracy of diagnosis achieves 94%. Compared with the existing algorithms, detection method based on uniform pattern LBP-GLCM has higher diagnostic accuracy and efficiency. Specifically, detection method with uniform pattern LBP-GLCM can improve accuracy in comparison with single asphalt pavement paving segregation detection method, and it can improve efficiency in comparison with existing hybrid asphalt pavement paving segregation detection method. The results of this study can potentially be used for real-time detection of asphalt paving segregation.

Carbon is a fascinating element that can be found in a wide spectrum of materials and plays a significant role in diverse disciplines across the scientific community. Carbon nanomaterials take many forms with numerous applications. Controllably tailoring carbon nanomaterials at the molecular scale can be considered as a basic innovation yet remains a significant challenge because of carbon’s intrinsic structural and chemical stability. Herein, we report a molecular scissor to efficiently tailor carbon nanomaterials of different dimensions at a molecular level. By using the Mg/Zn bimetallic effect and CO2 molecules, a molecular scissor was invented to engineer the surface of carbon nanomaterials with highly interconnected graphene pillared superstructures. The molecular scissor redesigned the carbon materials with improved surface properties for use in various applications. For energy storage application, both ultrahigh surface area and conductivity can be achieved concurrently with substantial ion-reserved accommodation and rapid mass-transfer expressway. As a demonstration, a flexible solid-state supercapacitor based on the surface-tailored carbon fiber was developed with Polyvinyl alcohol(PVA)/Na2SO4 gel electrolytes. It delivered a remarkably high energy density of 4.63 mW h cm–3 at a power density of 3520 mW cm–3. This work paves a new way to reinvent carbon materials at the molecular scale and promote their applications for energy storage, sensing, environmental remediation, and healthcare.

We propose a method of modelling the infiltration process of a liquid aluminium matrix into a porous silicon carbide particle (SiCp) preform based on porous medium geometry obtained from scanning electron microscopy (SEM) images. Our simulation illustrates that via a pore-scale, two-phase flow model, an improved description of the flow structure in the porous medium can be obtained compared with the description offered by traditional methods, such as those based on the capillarity and wetting conditions of porous media and Darcy’s law, the Brinkman equations or Richards’ equation. Simultaneously, we validate the proposed model by comparing simulated and experimental data. In particular, the simulation results successfully capture several important features of a pore-scale, two-phase flow: the evolution of the flow front during the infiltration process, the most probable locations of potential defects, the preferential flow paths, the pressure distribution, the velocity field and the permeability of the porous SiCp preform.

Direct alcohol fuel cell (DAFC) exhibits multiple unique advantages, such as high energy conversion efficiency, low cost, ready availability of fuels, minimal environmental pollution, and ease of operation, and has found diverse applications as a small, micro mobile power supply. A critical challenge for the development of DAFC is the design and engineering of effective anode catalysts, where electrooxidation of alcohols occurs. Within this context, two-dimensional (2D) electrocatalysts represent a viable option, due to their unique materials properties, such as large surface area, ease of charge migration and mass transfer, and mechanical robustness during electrochemical reactions. In this review, we summarize recent breakthroughs in the structural engineering of a range of 2D functional nanomaterials, including noble metals and alloys, metal oxides/hydroxides, metal carbides, and precious metal-based nanocomposites, in the electrocatalytic oxidation of alcohols (primarily methanol and ethanol), within the context of reaction mechanisms, and include a perspective highlighting the promises and challenges in future research.

Developing lightweight, flexible, and foldable electrodes with decent mechanical durability and electrochemical activity is a highly desirable goal for solid-state electrochemical energy storage devices yet remains a formidable challenge to overcome. Herein, we invent a freestanding robust PANI membrane via introducing the dynamic boronate bond to bridge rigid PANI chains with complaint polyvinyl alcohol (PVA) chains. The resultant PANI/PVA membrane (PPM) exhibits remarkable elasticity (17.8% strain) along with excellent tensile strength (33.7 MPa), outperforming the majority of existing state-of-the-art flexible electrochemical PANI membranes. Additionally, the PPM can be further assembled into a wearable solid-state supercapacitor with high electrochemical performance as well as decent mechanical durability. The lightweight, flexible, and foldable PANI membrane represents a great advancement in electrode materials for next-generation wearable solid-state electrochemical energy storage devices.

Approximately 22% of the 86 million people in the United States living with prediabetes are unaware of their condition. Detection of acetone in human respiration offers an effective and painless approach for the diagnosis of prediabetes. In this work, a wearable active acetone biosensor employing chitosan and reduced graphene oxide (RGO) as sensitive materials was developed to non-invasively diagnose prediabetes. When operated under 97.3% relative humidity at room temperature, the prepared chitosan and RGO composite film-based sensor exhibited a good sensing response of 27.89% under 10 ppm acetone in respiratory gases, which is about 5 times higher than the sensing response of pure chitosan film-based devices. In addition, finite element analysis and phase-field simulation were conducted to provide theoretical support for the active sensing mechanism. This work not only presents a wirelessly powered wearable active acetone biosensor, but also paves the way for a new method of non-invasive prediabetes diagnosis.

At 18:07 on September 5, 2018 (UTC), a Mw 6.6 earthquake struck the Iburi-Tobu area of Hokkaido, Japan. The Hokkaido Iburi-Tobu (HIT) earthquake is a reverse-slip earthquake with a focal depth of 33.4 km at 42.69°N and 142.07°E. According to the detailed landslide interpretations, there were approximately 7059 landslides induced by this earthquake concentrated in an area of 466 km2. The landslides induced by the HIT earthquake are mostly shallow landslides whose sources are mainly an air-fall pumice layer from the Tarumai volcano, and these landslides exhibit an obvious characteristic of a “low affected area, large landslide area”. The landslide area follows an exponential distribution, and many landslides are composed of multiple subsource areas. There are at least 8778 source areas in the whole landslide area. The landslides present high mobility, and the landslide deposits not only accumulate on the foot but also “flow” down along the gullies, similar to debris flows, despite the gullies being gentle (

Under the time theme of the energy crisis and environmental pollution, a great deal of attention has been devoted to the field of supercapacitors (SCs) for relieving this situation. Two-dimensional (2D) materials show great potential in various energy storage fields due to their unique and attractive characteristics. Especially, different types of 2D spinel structured Co-based MCo2O4 (M = Co, Ni, Zn, Cu, Fe, and Mn) materials are supposed to be promising candidates of electrode materials for SCs, which ascribes to their natural abundance and superior electrochemical performances including relatively high electron conductivity, rich electroactive sites, high specific capacitance, and good cycling stability. Moreover, 2D spinel structured Co-based materials can incorporate with other nanomaterials to form various diverse composites such as heterostructures, carbonaceous composites, transition metal oxide (TMO) composites, transition metal hydroxide (TMH) composites, transition metal sulfide (TMS) composites, transition metal phosphide (TMP) composites, and ternary composites, which can deliver satisfactory electrochemical performances. In this review, we highlighted the 2D spinel structured Co-based materials and their composites for SC applications. Finally, the future challenges and outlooks of 2D spinel structured Co-based materials in energy storage devices were also discussed.

The shock resistance of ship piping systems is very difficult to study owing to the large scales of such systems, and the high level and variability of the impact loading involved. To address these issues, the present work establishes a numerical model of pipe systems based on multi-span beam bending moment theory. An analysis of the bending moments of different multi-span continuous beams under static loading demonstrates that the simplified model employing just five spans provides a bending moment for target equal diameter straight tube (EDST) segments that deviates from theoretical calculations by less than 1%. Moreover, the bending moments obtained by the five-span model for a target EDST segment deviate by only about 4% from corresponding results obtained by the finite element (FE) method under both uniformly distributed static loading and complex static loading. The proposed simplified five-span model is then employed to calculate the stress responses obtained at individual critical points in a complex piping system under impact loading. The results obtained deviate at most by less than 15% from corresponding results obtained from the FE method based on the overall piping system model. Moreover, the average deviation for all critical points considered was only 5.87%. The results show that the shock response obtained using the simplified five-span model is essentially equivalent to that of the complex model. The proposed simplified five-span method is thereby demonstrated to be reasonable for simplifying large-scale complex piping systems when conducting shock resistance research.