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Na3V2(PO4)3 is a very prospective sodium-ion batteries (SIBs) electrode material owing to its NASICON structure and high reversible capacity. Conversely, on account of its intrinsic poor electronic conductivity, Na3V2(PO4)3 electrode materials confront with some significant limitations like poor cycle and rate performance which inhibit their practical applications in the energy fields. Herein, a simple two-step method has been implemented for the successful preparation of carbon-coated Na3V2(PO4)3 materials. As synthesized sample shows a remarkable electrochemical performance of 124.1 mAh/g at 0.1 C (1 C = 117.6 mA/g), retaining 78.5 mAh/g under a high rate of 200 C and a long cycle-performance (retaining 80.7 mAh/g even after 10000 cycles at 20 C), outperforming the most advanced cathode materials as reported in literatures.

In order to reduce the capacity degradation and improve the rate performance of LiNi0.5Co0.2Mn0.3O2 (NCM523), some decisive factors including structural stability, electronic conductivity and lithium ion diffusion coefficient are envisaged to be increased. For this purpose, surface coating with high electronic or ion conductive materials is generally conducted. Previous studies have proved that V2O5 possesses superior Li+ intercalation/deintercalation ability and low Li+ diffusion barrier, and graphene has high electronic conductivity and great HF resistance. Thus, the graphene/V2O5 co-coating is designed to improve the electrochemical performances of NCM523 in this study. The modified material retains a stable structure with low polarization and impedance. Besides, the discharge capacity is 207.7 mAh/g with 14.4 mAh/g improvement and the capacity retention is 93.1% with 7.6% enhancement at 0.1 C (1 C = 180 mAh/g) between 3 and 4.5 V after 100 cycles, and the rate performance approaches to 108.5 mAh/g at 10 C with the increasement of 54.3%. The improved performances are attributed to the following reasons: the co-coating effectively resists HF attacks on NCM523; lithium ion diffusion coefficient, storage capacity and electronic conductivity of the cathode material are simultaneously improved.

Layered LiNi0.6Co0.2Mn0.2O2 as a promising cathode material for lithium-ion batteries possesses high theoretical capacity and broad application prospects. However, the destruction of structure during the cycles and the insufficient conductivity severely restrict the cycle life and rate capacity, especially at high cut-off voltage. As an improvement, the dual-coating of LiAlO2 and graphene oxide (GO) was designed to modify the microstructure and migration dynamics of NCM622 surface. Compared to single coating, LiAlO2/GO showed a synergistic effect that simultaneously increased ion/electron transfer rate, reversibility and cycling stability of the cathode material. As a result, the initial capacity of the dual-coating material was 182.6 mAh/g at 200 mA/g (1 C) with a capacity attenuation of 0.06% per cycle in 200 cycles, while it was 222.6 mAh/g at 20 mA/g (0.1 C), and the rate capacity was 100.4 mAh/g at 2000 mA/g (10 C) in a voltage range of 3.0–4.5 V.

Dielectric barrier discharge (DBD) reactor at non-thermal plasma (NTP) in combination with catalysts was used to remove toluene in air. Several manganese oxides catalysts with ZSM-5 zeolite as the carrier have been prepared for plasma-catalytic degradation of toluene. The prepared catalysts were characterized utilizing the scanning electron microscopy (SEM), transmission electron microscope (TEM), H2 temperature-programmed reduction (H2-TPR), X-ray diffraction (XRD), and N2 adsorption–desorption. And the residence time, plasma power, toluene concentration and specific input energy, which are critical operating factors in this process, were investigated. The experiment proved that the catalysts significantly improved the degradation effect of NTP, the conversion increased from 58 to 91.5% after loading MnOx/ZSM-5-300 at 750 ppm, and the improving trend became more obvious with the increase of concentration. The degradation of toluene can reach 92.4% at the optimal process parameters of residence time 5.8 s, initial concentration 1000 ppm, input power 30 W, SIE 6000 J/L. The results of the evaluation indicate that it is very effective to use MnOx/ZSM-5 catalyst combined with DBD-plasma for synergistic degradation of toluene at room temperature and a relatively low energy consumption.

Warm compression deformation of Fe–13.5%Cr–4.7%Al–2.0%Mo–0.70%Nb–0.40Ta (wt%) (FeCrAl) and Fe–13.5%Cr–4.7%Al–2.0%Mo–0.45%Nb–0.40Ta–0.11Zr (wt%) (FeCrAl–Zr) ferritic stainless steel was performed by a thermal simulation machine Gleeble 3800 at 600 °C and strain rates of 0.01–10 s−1. Before deformation, all the samples were solution-annealed for 2 h at 1150 °C for FeCrAl alloy and 1250 °C for FeCrAl–Zr alloy. The strain rate has little or no effect on peak stress, and the precipitates in matrix or grain boundary precipitates (GBPs) have no difference in the samples deformed at the strain rate 0.01 s−1 and 1 s−1 both in FeCrAl and FeCrAl–Zr alloys. The addition of Zr increased the proportion of low-angle grain boundaries (LAGBs). The Laves phase in FeCrAl alloy precipitated uniform in the matrix, while in FeCrAl–Zr alloy Laves phase precipitated at grain boundary and formed GBP. The LAGBs and Σ3 coincident site lattice (CSL) grain boundary both increased in FeCrAl–Zr alloy, which possessed some beneficial properties such as high-temperature creep resistance to the Fe–Cr–Al alloy. More interesting, twins were created by warm deformation, which was difficult in typical bcc ferrite alloy. These results could be expected to provide guidance for subsequent warm working processes for the alloy.

In phytopathogenic fungi, the Hog1 MAPK pathway plays roles in osmoregulation, oxidation responses, fungicide sensitivity, among others. However, how fungi depend on the HOG MAPK pathway to regulate their functions is poorly understood. To further elucidate the molecular mechanisms of the HOG MAPK pathway, a yeast two-hybrid (Y2H) system was adopted to screen interacting proteins of two key components (CsPbs2 and CsHog1) of the HOG MAPK pathway in a cDNA library of Colletotrichum siamense. The results showed that 19 proteins may interact with CsPbs2, including cytochrome P450 4F5, ceramide very-long-chain fatty acid hydroxylase SCS7, the oxidative stress response two-component system protein SSK1, and other proteins. Twenty-one proteins may interact with CsHog1, including the cell wall protein PhiA, acriflavine sensitivity control protein acr-2, arachidonate 15-lipoxygenase, respiratory supercomplex factor 2-like protein, and others. Five proteins interact with both CsHog1 and CsPbs2: antigenic thaumatin-like protein, aspirochlorine biosynthesis protein N, secreted beta-glucosidase sun 1, alcohol dehydrogenase 1, and hypothetical protein GQ607_005106. Furthermore, the interaction of CsSCS7 and CsCytP450 4F5 with CsPbs2 was verified by His pull-down. qPCR revealed significantly upregulated CsPbs2, CsHog1, CsSCS7 and CsCytP450 4F5 expression in Colletotrichum treated with 50 μg/mL fludioxonil for 2 h. This research identified candidate CsHog1- and CsPbs2-interacting proteins via a Y2H system and confirmed the interactions of CsSCS7 and CsCytP450 4F5 with CsPbs2. The findings lay the foundation for further studies of HOG MAPK pathway function and regulatory mechanisms, especially regarding fungicide sensitivity.

Interaction of the conjugated structure in melanin contributed to photothermal conversion. Inspired by this, here, we first demonstrated that lignin nanoparticles (L-NPs) can carry out photothermal conversion, which was attributed to π-π stacking of lignin molecules. Lignin can be readily converted into L-NPs, using the self-assembly method at room temperature. L-NPs showed a stable photothermal effect (22%). The L-NPs were successfully used to power a thermoelectric generator and drive a solar steam generation device under standard 1 sun irradiation (100 mW/cm2). Because thermoelectric generators and solar steam generation technologies have huge potential for energy generation and water purification, the as-prepared L-NPs are expected to provide an important contribution to sustainable energy and clean water production.

High gas barrier polyethylene (PE) composites containing non-oxidized graphene flakes (GFs) were fabricated through solution blending. GFs were synthesized through ultrasonic-assisted electrochemical exfoliation of graphite. Then, GFs were functionalized via directly inducing PE molecular crystallization along their surface under proper temperature and PE/GFs ratio. The composites with only 0.5 wt% GFs gave a helium leak rate of 6.29 × 10−8 Pa m3/s at 0.6 MPa, outperforming pure PE with a decrease of 83.4%. In addition, the interface interaction between PE and GFs is very weak, and the cohesive energy is only 0.1448 J m−2. Therefore, at high GFs concentrations (>0.5 wt%), the continuous weak interfaces between the GFs interconnected networks and PE will reduce the effective diffusion path to a certain extent, leading to the reduction of gas barrier efficiency. In general, this method offers great promise for barrier materials that can be utilized in lightweight high-pressure gas storage vessels.

With the increasing importance of human–machine interactions, stretchability, biocompatibility, and self-healing behavior will play a more significant role in next-generation touch panels so as to allow integration with the human body. However, profound challenges remain because the electrodes of most touch panel are constructed by stiff and brittle materials lacking a self-healing capacity. Herein, we demonstrate a semiconductive touch panel that adopts a capacitive touch-sensing system, based on a poly(N,N′-dimethylacrylamide)–titanium dioxide nanocomposite hydrogel as a transparent conductor. The panel exhibited high stretchability, softness, low parasitic capacitance, high resolution, fast response, and instant functionality recovery upon damage. The panel was stretched to more than 1100% areal strain and could still be operated as an input device without sacrificing its functionalities. Furthermore, the distortion near the edge of the panel, owing to the nonlinearity of the resistance proved by the electrical finite element method simulation, became weaker after optimizing with a four-terminal pattern through 3D printing. An epidermal touch panel adhered to the human skin, and demonstrated strong performance and self-healing ability by being able to write words, play chess, and play games.

Background Heat resistance is a common characteristic of harpins, a class of proteins found in Gram-negative bacteria, which may be related to the stability of coiled-coil (CC) structure. The CC structure is a ubiquitous protein folding and assembly motif made of α-helices wrapping around each other forming a supercoil. Specifically, whether the stability of the CC structure near to N-terminus of four selected harpin proteins from Xanthomonas (hereafter referred to as Hpa1) would influence their characteristics of heat resistance was investigated. We used bioinformatics approach to predict the structure of Hpa1, used the performance of hypersensitive response (HR)-induction activity of Hpa1 and circular dichroism (CD) spectral analyses to detect the relationship between the stability of the CC structure of Hpa1 and heat resistance. Results Each of four-selected Hpa1 has two α-helical regions with one in their N-terminus that could form CC structure, and the other in their C-terminus that could not. And the important amino acid residues involved in the CC motifs are located on helices present on the surface of these proteins, indicating they may engage in the formation of oligo mericaggregates, which may be responsible for HR elicitation by harpins and their high thermal stability. Increased or decreased the probability of forming a CC could either induce a stronger HR response or eliminate the ability to induce HR in tobacco after high temperature treatment. In addition, although the four Hpa1 mutants had little effect on the induction of HR by Hpa1, its thermal stability was significantly decreased. The α-helical content increased with increasing temperature, and the secondary structures of Hpa1 became almost entirely α-helices when the temperature reached 200 °C. Moreover, the stability of the CC structure near to N-terminus was found to be positively correlated with the heat resistance of Hpa1. Conclusions The stability of the CC structure might sever as an inner drive for mediating the heat resistance of harpin proteins. Our results offer a new insight into the interpretation of the mechanism involved in the heat resistance of harpin protein and provide a theoretical basis for further harpin function investigations and structure modifications.

A new and effective method was developed for the synthesis of aromatic nitriles from arylacetic acids by using NaNO2 as the nitrogen source and Fe(OTf)3 as the promoter at 50 °C. A series of arylacetic acids underwent this transformation to give the targeted products in yields of 51–90%. Because of the mild conditions, the reaction is compatible with a broad range of functional groups, including ester, carboxy, hydroxy, acetamido, halo, nitro, cyano, methoxy, and even highly reactive formyl groups.

In this article, three-dimensional nanoporous Cu/Cu6Sn5 microparticles (3D-NP Cu/Cu6Sn5 MPs) were prepared by one-step chemical dealloying of Cu20Sn80 (at%) alloy slices in a mixed aqueous solution of HF and HNO3 and then filled into a three-dimensional porous copper foam (3D-PCF) skeleton as anode (3D-PCF@Cu/Cu6Sn5) for lithium-ion batteries (LIBs). The results show that the ellipsoidal 3D-NP Cu/Cu6Sn5 MPs with feature sizes of 3 to 8 μm are composed of numerous uniform nanoparticles (100 to 200 nm) and plenty of voids. Compared with similar Sn-based electrodes in this work and other published reports, the as-prepared electrode delivers more outstanding electrochemical performance with a superior reversible capacity of 1.90 mAh cm−2, 84.44% capacity retention and > 99.5% coulombic efficiency upon 200 cycles. The cycling stability and integrity of the overall structure of the composite electrode have been greatly enhanced under the synergistic effect of the buffer effect of copper as the inactive component, the unique hierarchical porous electrode architecture and the effective limitation in three dimensions of the 3D-PCF skeleton. We are confident that this work can provide new-generation LIBs with a promising anode candidate and a facile method of dealloying, and a subsequent filling step can achieve the practical production and application of high-performance LIBs.

Forest resources are among the most important wealth on the earth. Therefore, rational utilization of woods and improving its service efficiency will introduce profound social significance and economic benefits. But general surveys find that incorrect treatment of moisture content in wood products causes increasingly severe quality problems. So an efficient and nondestructive detection of wood moisture content is of extremely necessary and great importance. Whereas the present research tools are either time-consuming, environmentally sensitive, or too expensive to afford. This work proposes a convenient measurement of wood component’s moisture content through Channel State Information (CSI) of the Wi-Fi signal and its corresponding high precise hybrid feature extraction via Bimodal Deep Extreme Learning Machine (BDELM). We first set up a moisture content detection equipment with commodity Wi-Fi devices, then we acquire and process the CSI data which pass through the wood component. After that, the BDELM is adopted to calculate the integration of CSI’ amplitude and phase data. Finally, the moisture content will be accurately distinguished by offline training and an online testing procedure. Our results show that the proposed method could achieve a classification accuracy of moisture content detection above 96% for six different wood components, which demonstrates its effectiveness in application scenarios like wooden structure health monitoring.

The interfacial property of sized carbon fiber reinforced vinyl ester resin (SCF/VE) composite was improved by a self-migration method using acrylamide (AM) as a modifier. A molecular dynamics simu...

Internet of Things (IoT) is a very promising technology in forest engineering, especially for the environment and plant growth monitoring. LoRa Wide Area Network (LoRaWAN) is a prevailing choice for the Forestry IoT owing to its low-power and long-range ability. Real-world deployment and network optimization require accurate path-loss modeling, so the LoRaWAN radio channel in the forest is needed to be intensively studied. However, most of the subsistent propagation models do not involve specific forestry environmental parameters. In this paper, two parameters related with the trees are considered: the leaf area index and the tree trunk diameter. Due to the time-changing characteristics of these two items (from spring to winter), an empirical model has been developed through extensive measurement campaigns: Firstly, the channel measurement platform is designed based on a real scene of mixed forest. Secondly, the fading characteristics of the channel transmission for LoRa nodes are tested, and the corresponding model is presented and evaluated. Lastly, an energy harvesting LoRaWAN is deployed and operated in a sampled forest region of Eastern China for environment monitoring based on our propagation model. The results show that 433 MHz LoRa path loss in the mingled forest could be precisely predicted by our proposed model. Moreover, network coverage and energy consumption optimization of the LoRa nodes could be performed, which enables the perpetual development of reliable forestry evolution monitoring system.

Indoor pollutants, such as formaldehyde, pose an increasing threat to human health. Here, regenerated cellulose was combined with a novel visible light-responsive photocatalyst, La0.3Sr0.7TiO3, to ...

Chemical transformations determine the structure of a product, and therefore its properties, which in turn affect complex macroscopic functions such as the metabolic stability of pharmaceuticals or the volatility of perfumes. Therefore, reaction selection can influence the success or failure of a candidate molecule to meet a functional objective. The coupling of an amine with a carboxylic acid to form an amide bond is the most popular chemical reaction used for drug discovery1. However, there are many other ways to connect these two common functional groups together. Here we show computationally that amines and acids can couple via hundreds of hypothetical yet plausible transformations, and we demonstrate experimentally the application of a dozen such reactions. To investigate the contribution of chemical transformations to properties, we developed a string-based notation and used an enumerative combinatorics approach to produce a map of conceivable amine–acid coupling transformations, which can be charted using chemoinformatic techniques. We find that critical physicochemical parameters of the products, such as partition coefficient and polar surface area, vary considerably depending on the transformation chosen. Data mining the amine–acid coupling system produced here should enable reaction discovery, which we demonstrate by developing an esterification reaction found within the mapped space. Complex molecules with distinct property profiles can also be discovered within the amine–acid coupling system, as we show here via the late-stage diversification of drugs and natural products. All possible chemical transformations between amine and carboxylic acid groups are mapped using an automated string-based combinatorics method, showing that the properties and functions of the products vary considerably over all plausible reactions.

The miniature soft robots have many promising applications, including micro-manipulations, endoscopy, and microsurgery, etc. Nevertheless, it remains challenging to fabricate a miniatured robot device that is thin, flexible, and can perform multimodal locomotor mobility with sensory capacity. In this study, we propose a miniatured, multi-layer (two shape memory polymer layers, a flexible copper heater, a silk particle enhanced actuator layer, and a sensory layer) four-limb soft robot (0.45-gram, 35 mm-long, 12 mm-wide) with a total thickness of 1 mm. A precise flip-assembling technique is utilized to integrate multiple functional layers (fabricated by soft lithography, laser micromachining technologies). The actuator layer's elastic modulus increased ∼100% by mixing with 20% silk particles by weight, which enhanced the mechanical properties of the miniature soft robot. We demonstrate that the soft robot can perform underwater crawling and jumping-gliding locomotion. The sensing data depicts the robot's multiple bending configurations after the sensory data been processed by the microprocessor mounted on the robot torso. The miniatured soft robot can also be reshaped to a soft miniatured gripper. The proposed miniatured soft robots can be helpful for studying soft organisms’ body locomotion as well as medical applications in the future.

To apply the dental Co-Cr-Mo-W alloy restorations fabricated by selective laser melting to clinical use cases, it is necessary to perform a subsequent heat treatment (HT) after SLM processing. However, investigations regarding the effects of HT temperatures on microstructures and mechanical properties inherent in SLM-manufactured Co-Cr-Mo-W alloys are still insufficient. In this article, the microstructure variation during HT at different temperatures and its effect on mechanical properties were systematically investigated and discussed. The Co-Cr-Mo-W dental alloys fabricated by SLM were heat treated at 750 °C, 850 °C, 950 °C, 1050 °C, and 1150 °C for 1 hour and subsequently air cooled. Then, the microstructures were characterized and the mechanical properties evaluated. The results showed that, during HT, Co3(Mo, W)2Si intermetallic compounds with hcp crystal structures precipitated in specimen matrixes and at grain boundaries. With heat treatment temperatures increasing from 750 °C to 950 °C, the number of precipitates gradually increased, and the volume gradually grew. When the temperature increased to ≥ 1050 °C, the number of intermetallic compounds decreased. On the other hand, with increasing HT temperatures, the content of e-Co phases increased initially but then dropped, reaching a maximum of 97.5 pct at 950 °C and a minimum of 4.4 pct at 1150 °C. Furthermore, there is a coherent relationship between hcp phases (e-Co) and fcc phases (γ-Co), and the two lattice cells allow the relative orientation of {0001}e//{111}γ, 〈11-20〉e //〈110〉γ. Mechanical test results showed that, with increasing HT temperatures, the 0.2 pct yield strength (0.2 pctYS) and ultimate tensile strength (UTS) increased initially and then dropped, reaching a maximum value at 850 °C. Conversely, the ductility decreased initially and then rose, reaching a minimum at 850 °C and 950 °C. The mechanical properties depended primarily on the change of volume fractions of the e-Co in mixture as well as the size, morphology, and distribution of precipitates. Additionally, specimens heat-treated at 1050 °C for 1 hour were superior to as-SLM (AS) specimens in both strength and ductility.

Freestanding 3D nanoporous Cu-supported Cu2O hierarchical nanoplate arrays (3D NPC@Cu2O HNPAs) have been prepared in situ by facile one-step oxidation-assisted electrochemical dealloying, in which Cu2O HNPAs are characteristic of large-sized (hundreds of nm) 2D nanoplate arrays firmly embedded in small-sized (tens of nm) counterparts. The unique 3D nanocomposites as anodes for Li-ion batteries (LIBs) display superior Li storage properties involving ultrahigh specific capacity, long cycle life and excellent rate capability, which deliver a reversible capacity as high as 3.0 mAh cm−2 with 71.4 pct capacity retention after 450 long cycles at 2 mA cm−2. Even when the current density reaches 5 mA cm−2, an ultrahigh reversible capacity of 3.4 mAh cm−2 still can be achieved smoothly without obvious capacity decay after 250 cycles. It is totally comparable to or even exceeds the current level of a commercial graphite anode. The outstanding electrochemical performance can be largely ascribed to the unique 3D electrode structure comprising HNPAs and NP substrate, the large contact area between active material and electrolyte, in situ growth of active material upon the porous substrate, a compact joint of small-sized intermediate nanolayers and favorable mass transfer among vertical hierarchical nanoplates, indicative of a quite promising candidate as a binder-free integrated anode toward practical application of advanced LIBs.

CAP20 is a lipid droplet-coating protein perilipin homolog that plays a key role in Colletotrichum functional appressorium development and virulence. To obtain proteins interacting with CAP20 in Colletotrichum, the bait protein expression plasmid pGBKT7-Cap20 and the cDNA library of Colletotrichum siamense (the major causative species of rubber tree anthracnose) was constructed. By yeast two hybrid system, sixteen proteins, including a cAMP-dependent protein kinase catalytic subunit (PKAC1), protein kinase, acetate kinase, hydrophobin, and hypersensitive response-inducing protein, may interacting with CAP20 were identified after sequencing and bioinformatics analysis. Furthermore, the interaction between CAP20 and the catalytic subunit of protein kinase A (PKAC1) was validated by GST pull-down analysis in vitro and co-immunoprecipitation (co-IP) assays in vivo. qPCR revealed a positive correlation between the expression of PkaC1 and Cap20 in Colletotrichum treated with PKA activators or inhibitors. This research identified candidate proteins by the yeast two-hybrid system and confirmed an interaction between the pathogenicity-related protein CAP20 and PKAC1. The findings lay the foundation for further studies of the function and regulation mechanism of CAP20.

Recently, in the arena of finding substitutes for lead-containing perovskite solar cells, the oldest selenium solar cells (SSCs) have been reconsidered by many scientists due to their suitable energy level structure and less-toxic nature. A lot of research efforts have been made to improve the efficiency of SSCs through seeking suitable substrates and modifying the process of Se crystallization. However, little attention has been paid to investigating the stability of SSCs. In addition, one crucial point that is neglected by researchers could be the potential applications of low-cost SSCs in complicated and tough environments, owing to the intrinsic physicochemical resistance of the Se material. To address these issues, in this research, SSCs with an elaborately designed architecture have been presented, and the highest efficiency (3.7%) among SSCs with organic hole transport layers was achieved. Additionally, a dozen of P3HT-based SSCs were demonstrated to maintain 92% efficiency after more than 1500 hours. The favorable long-term stability of the SSCs allowed us to carefully analyze the changes in each dynamic parameter during aging and helped explore the factors that affect the device behaviors. These results would pave the way for the application of the ultra-stable SSCs in harsh conditions. Ministry of Education (MOE) Q. Z. acknowledges financial support from AcRF Tier 1 (RG 111/17, RG 2/17, RG 114/16, RG 8/16) and Tier 2 (MOE 2017-T2-1-021 and MOE 2018-T2-1-070), Singapore.

Increasing the active site density of single atom catalysts (SACs) is expected to generate closely neighboring atomic sites with potential synergetic interaction. However, the synthesis of SACs with high active site density still remains a great challenge due to the easy aggregation of high density metal atoms during the synthesis. In the present work, we develop a stepwise anchoring strategy for the large-scale preparation of carbon-supported high-density Pt SACs (denoted as PtSA@BP). The Pt loading of PtSA@BP is as high as 2.5 wt%, leading to the observation of abundant closely distanced single Pt sites. The produced PtSA@BP catalyst exhibits ultrahigh catalytic activity for the alkaline hydrogen evolution reaction with a low overpotential of 26 mV at 10 mA cm−2 in 1.0 M KOH under ultralow Pt loadings of 0.0009 mgPt cm−2 on the electrode, much superior to commercial Pt/C (20 wt%). Mechanistic studies suggest the main contribution of the coordination of closely distanced three-coordinated PtC2N1 moieties to the excellent catalytic activities towards the conversion of water to H2, due to their close-to-zero metal–hydrogen binding value and intense adsorption capability to H2O molecules as well as their low water-dissociation energy barrier. More importantly, this strategy has been verified to be feasible for preparing other noble-metal based SACs, for example, Rh and Pd. The present result provides an enabling and versatile platform for facile access of SACs with technological importance in various areas.

One of key factors to design applicable electron transport layers (ETLs) for perovskite solar cells is the morphology of ETLs since a good morphology would help to facilitate the carrier transport at two interfaces (perovskite\ETL and ETL\cathode). However, one drawback of most organic ETL small molecules is the internal undesired accumulation, which would cause the formation of inappropriate morphology and rough ETL surface. Here, by elaborately designing the side chains of NDI derivatives, the molecular interaction could be modified to achieve the aggregation in different degrees, which would eventually affect the accumulation of molecules and surface qualities of ETLs. By speculating from the comparison between the absorption spectra of solutions and films, the sequence of extent of molecule interaction and aggregation was built among three NDI derivatives, which is further confirmed by direct evidence of atomic force microscopy (AFM) images. Then, carrier exaction abilities are simply studied by steady-state photoluminescence spectroscopy. The carrier transport process is also discussed based on cyclic voltammetry, time-resolved photoluminescence spectroscopy and mobility. NDIF1 are proven to have the appropriate internal aggregation to smooth the contact with cathode and low series resistance, and a device performance of 15.6 % is achieved. With the ability of preventing the thermal diffusion of Ag towards the perovskite surface due to the strong interaction between molecules, NDIF2 at high concentration shows the highest fill factor (80 %).

In order to better study the creep properties of rock under different stress and time, the creep test was taken from the surrounding rock of the roadway. First, a model that describes the whole process of rock creep was introduced so that it could correspond to the various stages of creep. Then, a new method for determining creep parameters was proposed. The calculated creep parameters were processed by combining the stress difference and the time product, and the relationship between the creep parameters and the overstress difference and time product was analyzed. A creep model considering stress and time effects was obtained. Finally, the model was verified by the experimental data and calculation results, and the rationality and correctness of the method for determining the parameters of the creep model were analyzed. The results shown that the special point of creep curve and the definition of creep deformation were combined with the model equation and experimental data to determine the creep parameters under different stress and time. The improved creep model could better describe the creep damage process of rock under different stress states, and provided a new idea for establishing the unsteady creep model and determining the model parameters. The product of E2 controlled the limit of viscoelastic deformation gradually decreased with the product of time and overstress difference. The shear viscoelastic coefficient η1 gradually decreased as the product of time and overstress difference increases. The product of η2 controlling the steady creep rate decreased with time and the overstress difference. The higher the stress level, the greater the steady creep rate, but the overall stable creep rate was less than the accelerated creep rate. The nonlinear viscous coefficient η3 mainly controled the accelerated creep deformation of rock and gradually decreased with the increase of stress and time. The trend of creep parameters as a whole indicated that stress and time had certain degrading effects on rock creep parameters.

Fabricating ultrathin two-dimensional (2D) covalent organic framework (COF) nanosheets (NSs) in large scale and high yield still remains a great challenge. This limits the exploration of the unique...

Soft rot pectobacteria are devastating plant pathogens with a global distribution and a broad host range. Pectobacterium aroidearum L6, previously isolated from leaves of Syngonium podophyllum, is a pectolytic bacterial pathogen that causes typical soft rot on S. podophyllum. There is a shortage for genome data of P. aroidearum, which seriously hinders research on classification and pathogenesis of Pectobacterium. We present here the complete genome sequence of P. aroidearum L6. The L6 strain carries a single 4,995,896-bp chromosome with 53.10% G + C content and harbors 4,306 predicted protein-coding genes. We estimated in silico DNA–DNA hybridization and average nucleotide identity values in combination with the whole-genome-based phylogeny from 19 Pectobacterium strains including P. aroidearum L6. The results showed that L6 and PC1 formed a population distinct from other populations of the Pectobacterium genus. Phylogenetic analysis based on 16S rRNA and genome sequences showed a close evolutionary relationship among Pectobacterium species. Overall, evolutionary analysis showed that L6 was in the same branch with PC1. In comparison with 18 Pectobacterium spp. reference pathogens, strain L6 had 2,712 gene families, among which 1,632 gene families were identified as orthologous to those strains, as well as 1 putative unique gene family. We discovered 478 genes, 10.4% of the total of predicted genes, that were potentially related to pathogenesis using the Virulence Factors of Pathogenic Bacteria database. A total of 25 genes were related to toxins, 35 encoded plant cell-wall degrading enzymes, and 122 were involved in secretion systems. This study provides a foundation for a better understanding of the genomic structure of P. aroidearum and particularly offers information for the discovery of potential pathogenic factors and the development of more effective strategies against this pathogen.

Molecular dynamics (MD) method was conducted to investigate the interaction between symmetric tilt Σ5(2 1 0) 〈0 0 1〉 grain boundary (GB) and irradiation-induced point defects in Fe-9Cr alloy. Effects of the temperatures and distances from primary knock-on atom (PKA) to GB on the maximum number of defects and surviving number of defects were studied based on the calculated results. It is found that the maximum number of defects varied with the distance from GB to the PKA. The results also showed that the maximum number of defects had a positive correlation with temperature, while the surviving number of defects had a negative correlation with temperature. Further study showed that there was a higher recombination rate for the defects in grain interior than that in the vicinity of the GB, and the ratio of Cr atoms in interstitial atoms was slightly higher than that in the matrix.

Soil compaction is a major environmental problem that affects plant growth and development. In this study, to further our understanding of its negative effects on plant growth, we investigated the effects of soil compaction on the growth, mineral absorption, and activities of key respiratory enzymes in soybean seedlings. We found that moderate-level soil compaction increased the activities of pyruvate kinase and phosphofructokinase in soybean seedling roots, enhancing the accumulation of P, K, Mg, Ca, and other elements. These accumulated elements, particularly Ca, increased the number of fibrous upper roots, but reduced root length and inhibited plant growth. High-level soil compaction inhibited the accumulation of P, K, Mg, Mn, Fe, Cu, and Zn and increased the accumulation of Ca via decreasing the activities of isocitrate dehydrogenase and cytochrome c oxidase. These effects led to a decreased root cell size, blurred root cell boundaries, and the inhibition of plant growth. Taken together, our results provide a new insight into the mechanisms by which soil compaction inhibits plant growth.

The role of sizing agent in the formation of interphase and the effect on the interfacial properties of carbon fiber (CF) reinforced vinyl ester resin (VE) composite were studied by molecular dynamics (MD) simulations. A novel unsaturated sizing agent N-(4′4-diaminodiphenyl methane)-2-hydroxypropyl methacrylate (DMHM) was used in this study. Epoxy sizing agent (E44) and modified epoxy sizing agent (ME44) were used for comparison. Simulation results showed that DMHM exhibited the highest interfacial bonding strength with CF surface due to the strong polarity of the sizing agent molecule. This result was confirmed by the interfacial shear strength test. The swelling effect of sizing agent in liquid VE was evaluated by solubility in styrene and compatibility with VE component. All three sizing agents had good solubility in styrene according to the calculation of total solvation free energy, while E44 and DMHM exhibited good compatibility with VE molecule based on the mixing energy calculation. The swelling property of sizing agent was confirmed by nano-indentation test. The results of this study explain the higher interfacial shear strength (62.25 MPa) between VE and CF sized by DMHM.

To clarify the effect of amorphous/amorphous (A/A) interfaces during ion irradiation, the He ion irradiation responses of ZrCu/ZrCuNiAlSi A/A nanolaminates (A/ANLs) as well as ZrCu and ZrCuNiAlSi single-layered amorphous thin films were examined. The results showed the A/ANLs exhibited superior irradiation resistance compared with the corresponding single-layered thin films, as the former possessed better microstructure stability and higher He ion solubility than the latter during He ion irradiation. Besides, A/ANLs having more interfaces exhibited even better irradiation resistance than those having less. The enhanced irradiation resistance of A/ANLs was attributed to the sink effect of A/A interfaces, which effectively reduced the amount of radiation-induced “defects” and He bubbles.

Water wave energy is regarded as one of the most prospective renewable energy sources, while most of it has not been utilized for numerous technology defects. As a new energy technology, triboelectric nanogenerator (TENG) has been widely utilized for low frequency and random mechanical energy harvesting, which is very suitable for scavenging water wave energy. In this paper, we present a torus structured triboelectric nanogenerator (TS-TENG) which consists of an inner ball and a torus shell. Triggered by water waves, the ball revolves in the torus shell for triboelectric power generation, and the TS-TENG can harvest random wave energy from all directions. Moreover, to scavenge large-scale water wave energy, the TS-TENG array is fabricated and presented as a power source for persistently powering electronic devices and charging a battery or capacitor. With an agitation frequency of 2 Hz and an oscillation angle of 5°, the TS-TENG is expected to give a maximum peak power density of 0.21 W/m2. Take advantage of low-cost, environment-friendly and easy- implement, the development of the TS-TENG is of great significance for harvesting large-scale ocean wave energy and other potential applications in blue energy.

Due to the introduction of ideal memristors, extreme multistability has been found in many autonomous memristive circuits. However, such extreme multistability has not yet been reported in a non-autonomous memristive circuit. To this end, this paper presents an improved non-autonomous memristive FitzHugh–Nagumo circuit that possesses a smooth hyperbolic tangent memductance nonlinearity, from which coexisting infinitely many attractors are obtained. By utilizing voltage–current circuit model, a three-dimensional non-autonomous dynamical model is established, based on which the initial-dependent dynamics is explored by numerical plots and extreme multistability is thereby exhibited. To confirm that the improved non-autonomous memristive circuit operates in hidden oscillating patterns, an accurate two-dimensional non-autonomous dimensionality reduction model with initial-related parameters is further built by using incremental integral transformation, upon which stability analysis and bifurcation behaviors are elaborated. Because the equilibrium state of the dimensionality reduction model is always a stable node-focus, hidden extreme multistability with coexisting infinitely many attractors is truly confirmed. Finally, PSIM circuit simulations validate the initial-related hidden dynamical behaviors.

As a vital biological mediator and a widely used industrial oxidant, the accurate detection of hydrogen peroxide (H2O2) is of significance for both academic purpose and practical applications. Herein, we report a novel approach for the development of a high-performance electrochemical H2O2 sensor constructed by iron phthalocyanine (FePc)-based diyne-linked conjugated polymeric nanosheets (NSs), FePc-CP NSs. The FePc-CP NSs were delaminated from the bulk material via a defect- and disorder-induced synthetic strategy. By the quasi-Langmuir-Shafer method, the prepared FePc-CP NSs were self-assembled into multilayer films with controllable thickness on electrodes. Owing to the highly exposed active centers on the surfaces, the FePc-CP NS film-modified electrodes exhibited excellent H2O2 determination performance with a wide linear detection range (0.1-1000 μM), a short response time (the response current approached the maximum value within 0.1 s), a low limit of detection (0.017 μM), and excellent sensitivity (97 μA cm-2 mM-1), which are comparable to the best results reported so far for electrochemical H2O2 sensors. In addition, the fabricated electrochemical H2O2 sensor also displayed satisfactory stability, reproducibility, and selectivity. Furthermore, the obtained FePc-CP NS film sensor can be applied in real-time monitoring of H2O2 in commercial orange juice and beer as well as H2O2 secreted from A549 live cells, revealing its application potential toward the accurate detection of H2O2 in real-sample analysis.

The steady-state assumption in the classical solute drag (SD) models is not always valid in treating the complex interaction between alloying elements and migrating interfaces (grain/phase boundaries) in steels. In this study, a general treatment based on phase-field theory is proposed to capture the SD effects of alloying elements without the steady state assumption, while it reduces to the SD models under steady-state assumption. This new treatment can predict the interaction between migrating interfaces and alloying elements with strong segregation tendencies, which cannot be captured by the classical SD models.

A triaxial creep test of the surrounding rocks in the Fuxin Hengda coal mine was performed using an MTS815.02 rock mechanics testing system. The damage variable of the rocks was deduced on the basis of the energy conservation law and minimum energy consumption theory. A nonlinear creep damage model was established. Results indicated that the internal porosity of the rocks is completely opened at the initial moment. The rocks demonstrated a certain amount of instantaneous deformation during the loading of pore compression closure. In addition, rock cracks developed and expanded with the complete closure of pores and an increase in stress. The axial and radial deformations of the rocks also increased dramatically. The established nonlinear creep model of rock damage can clearly reflect the law of stress and strain changes. Energy dissipation was also observed in damaged rocks. The new model can compensate for the shortcomings of traditional models that are difficult to describe in the accelerated creep phase. The final test and fitting curves presented high degrees of fitting. Thus, the reflection of the deformation law of the entire rock creep process by deriving the energy of the damage evolution equation is suitable and feasible. Keywords: Nonlinear, Unloading, Minimum energy dissipation principle, Accelerated creep

To prepare intelligent cellulose fiber (ICF), cellulose fibers were modified by grafting hydroxypropyltriethylamine groups to which bromothymol blue (BTB) was anchored. The ICFs were incorporated into cassia gum (CG) to prepare a pH-sensitive intelligent film. The Fourier transform infrared results indicated that BTB has been introduced in the CG-ICF5 film. Scanning electronic microscopy indicated that the addition of ICF can loosen the structure of the film. The incorporation of ICF decreased light transmittance and water vapor permeability but did not significantly affect thermal stability. The mechanical properties were weakened with 3% ICF addition and were improved with 5% ICF addition. The release experiment indicated that 46.784% and 8.297% of BTB was released from the CG-ICF5 film under oscillating to 50% and 95% alcohol/water solution, respectively. The response of the intelligent films to triethylamine in environments with different relative humidities was investigated. A visible color change occurred in the triethylamine environment within 20 min. Pork and chicken spoilage experiments were performed to study the application of the intelligent film in monitoring meat freshness during spoilage. Obvious color changes appeared, demonstrating that the intelligent film has potential for use in real-time indication of meat spoilage.

As an extension of traditional sparse representation (SR), kernel SR has received great interest recently in the areas of computer vision and pattern recognition. It shows a considerable capacity to map linearly inseparable data into high-dimensional feature space via nonlinear mapping technique, and has been widely used in target recognition problems. In this paper, we propose a new weighted multi-task kernel sparse representation method to solve the synthetic aperture radar (SAR) target recognition problem. To capture the spatial and spectral information of a SAR target simultaneously, the proposed method explores the monogenic signal transformation to generate multi-scale monogenic features at first. Then, the proposed method provides a unified framework, named multi-task kernel sparse representation, for SAR target classification. The framework implicitly maps monogenic features into a high-dimensional kernel feature space by using the nonlinear mapping associated with a kernel function. In the kernelized subspace, SAR target recognition is formulated as a joint covariate selection problem across a group of related tasks. Furthermore, a multi-task weight optimization scheme is developed to compensate for the heterogeneity of the multi-scale features and enhance the recognition performance. Extensive experimental results tested on the public moving and stationary target acquisition and recognition (MSTAR) dataset demonstrate that our proposed method achieves better recognition performance than other existing competitive algorithms.

Direct conversion of cheap methylarenes to benzylic amines, which are essential structural units of important drugs, is of great significance. However, the known methodologies suffer from the requirement of noble metal catalysts, heavy metal residues or strong oxidants. Herein, the first biocompatible iron-catalyzed benzylic C (sp3)–H amination of methylarenes with N-fluorobenzenesulfonimide is described. The reactions of methylarenes bearing electron-donating groups and electron-withdrawing groups ran smoothly under ligand and additional oxidant free conditions. Both toluene derivatives and 8-methylquinoline can be aminated by the same iron catalyst.

Minisci alkylation is of prime importance for its applicability in functionalizing diverse heteroarenes, which are core structures in many bioactive compounds. In alkyl radical generation processes, precious metal catalysts, high temperatures and excessive oxidants are generally involved, which lead to sustainability and safety concerns. Herein we report a new strategy using diacetyl (2,3-butanedione) as an abundant, visible light-sensitive and “traceless” hydrogen atom abstractor to achieve metal-free cross-dehydrogenative Minisci alkylation under mild conditions. Mechanistic studies supported hydrogen atom transfer (HAT) between an activated C(sp3)–H substrate and diacetyl. Moreover, with the assistance of di-tert-butyl peroxide (DTBP), the scope of the reaction could be extended to strong aliphatic C–H bonds via diacetyl-mediated energy transfer. The robustness of this strategy was demonstrated by functionalizing complex molecules such as quinine, fasudil, nicotine, menthol and alanine derivatives.

The magnesia–pullulan composite (MgOP) achieved effective fluoride removal in previous research. In the present study, an acid-base titration experiment was conducted to investigate the properties of MgOP surface and further explore the mechanism of fluoride adsorption on MgOP. Results showed that the presence of chloride ions could improve fluoride adsorption on MgOP; however, additional nitrate ions had negligible impacts. A diffuse layer model and chemical equilibrium software (Visual MINTEQ 3.1) were used to simulate the acid-base titration data. The effects of initial pH values on the rate of fluoride uptake by MgOP were also studied. Moreover, aluminum salts were added to the fluoride solution with MgOP for the pH neutralization of treated water, in which aluminum chloride was preferred.

Carbamazepine (CBZ), a widely used antiepileptic drug, is refractory to biological wastewater treatment. Rapid removal of CBZ is possible using synthetic manganese oxide (δ-MnO2) but the removal mechanisms require further investigation. In this study, CBZ degradation by δ-MnO2 was carried out at different pH to further explore the degradation mechanisms. Results show that CBZ degradation by δ-MnO2 was highly pH dependent, and rapid degradation occurred when pH

The mechanism of torque production in the Vernier machine is difficult to understand since the stator teeth originating flux modulation effects, upon which the torque is produced, are usually minor factors, which are ignored in normal synchronous machines. This paper begins with an analytical study of a spoke type Vernier permanent magnet machine (SVPM), which has a generic number of stator slots per pole per phase, upon which the key sizing equations are developed. An equivalent winding factor is defined to model stator teeth originating flux modulation phenomena and resulting multiharmonic field coupling effects. Performance predictions and design observations concerning SVPMs are then obtained. A new topology for an SVPM using ferrite magnets is proposed where a consequent pole design having an alternating leakage flux blocking ability is developed for the rotor. Overall, this improved SVPM design significantly boosts the back electromotive force compared to conventional SVPM, and the torque production even surpasses that of a benchmark rare earth interior permanent magnet machine (IPM) although with a slightly lower power factor.

In this paper, novel three dimensional hierarchical porous Sn-Ni (3D-HP Sn-Ni) alloys were investigated as a promising anode for high-performance Li ion batteries (LIBs), which was fabricated by pulse electrodeposition of mesoporous Sn-Ni alloy made of ultrafine nanoparticles on the 3D nanoporous copper substrate from chemical dealloying of as-cast Al55Cu45 (at.%) alloy slices in the HCl solution. The results show that the as-obtained 3D-HP Sn-Ni alloys are typically characteristic of open, bicontinuous, interpenetrating bimodal pore size distribution comprising large-sized (hundreds of nm) ligament-channel network architecture with highly porous channel walls (several nm). Compared to the two dimensional nanoporous Sn-Ni (2D-NP Sn-Ni) thin films, the 3D-HP Sn-Ni alloys as anode for LIBs show superior cycling stability with reversible specific capacity of 0.25 mAh cm−2 and coulombic efficiency of more than 95% up to 200 cycles. Moreover, the reversible capacity as high as 0.22 mAh cm−2 can be achieved even after a series of high-rate charge–discharge cyclings. The satisfactory electrochemical properties can be mainly ascribed to the unique 3D hierarchical porous structure, large contact surface area between active material and electrolyte, as well as good buffer effect of inactive component, which is greatly beneficial to alleviate the huge volume variation, enhance the loading mass of active material, shorten the Li+ migration distance and improve the electron conductivity. We believe that this present work can provide a promising anode candidate towards practical application of high-performance LIBs.

A molecular dynamics simulation was performed to investigate the migration of acrylamide (AM) to the carbon fiber (CF) surface from a liquid vinyl ester resin (VE), as well as the effect on the interfacial strength of CF/VE composite. The analysis of monomer concentration profile after the system equilibrium shows that an AM-rich interphase region was formed and the interfacial bond energy was increased. This can be explained by the greatest average atomic binding energy of AM with the CF surface. The migration of AM was confirmed experimentally by a depth profiling method using plasma etching and X-ray photoelectron spectroscopy. The AM molecules in interphase could chemically bond CF surface and VE matrix. As a result, the interface shear strength and interlaminar shear strength of CF/VE composite were enhanced by 126.98% and 81.86%, respectively.

The microstructural evolution of a nickel-based heat resistant alloy during long term aging (10000 h) at 700 °C was systematically investigated. Experimental results showed that the main precipitates after pre-aging treatments were MC, M 23 C 6 and homogeneous γ’ . The weight fraction of γ′ increased continuously with the aging time up to 5000 h, while an obvious coarsening was observed after aging for 100 h. The grain sizes of γ′ precipitates from all aged samples exhibited unimodal distributions, and their coarsening behavior showed good agreement with the LSW model. Compared to the MC carbides, the weight fraction of the M 23 C 6 carbides increased significantly with the increase of the aging time. This could be attributed to their precipitation from the supersaturated matrix. Due to the precipitation and coarsening of γ′, the hardness of the aged samples increased sharply during the first 100 h of aging and then decreased with the increase of the aging time (up to 10000 h).

Terpenes constitute the largest class of secondary metabolites in plants. Some terpenes are essential for plant growth and development, membrane components, and photosynthesis. Terpenes are also economically useful for industry, agriculture, and pharmaceuticals. However, there is very low content of most terpenes in microbes and plants. Chemical or microbial synthesis of terpenes are often costly. Plants have the elaborate and economic biosynthetic way of producing high-value terpenes through photosynthesis. Here we engineered the heterogenous sesquiterpenoid patchoulol production in A. annua. When using a strong promoter such as 35S to over express the avian farnesyl diphosphate synthase gene and patchoulol synthase gene, the highest content of patchoulol was 52.58 μg/g DW in transgenic plants. When altering the subcellular location of the introduced sesquiterpene synthetase via a signal peptide, the accumulation of patchoulol was observably increased to 273 μg/g DW. This case demonstrates that A. annua plant with glandular trichomes is a useful platform for synthetic biology studies.

Functional encryption (FE) is a novel paradigm for encryption scheme which allows tremendous flexibility in accessing encrypted information. In FE, a user can learn specific function of encrypted messages by restricted functional key and reveal nothing else about the messages. Inner product encryption (IPE) is a special type of functional encryption where the decryption algorithm, given a ciphertext related to a vector x and a secret key related to a vector y, computes the inner product x·y. In this paper, we construct an efficient private-key functional encryption (FE) for inner product with simulation-based security, which is much stronger than indistinguishability-based security, under the External Decisional Linear assumption in the standard model. Compared with the existing schemes, our construction is faster in encryption and decryption, and the master secret key, secret keys and ciphertexts are shorter.