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Atmospheric CO2 concentrations are soaring due to the continued use of fossil fuels in energy production, an anthropogenic activity that is playing a leading role in global warming. Thus, research aimed at the capture and conversion of CO2 into value-added products, such as cyclic carbonates, is booming. While CO2 is an abundant, cheap, non-toxic, and readily accessible C1 feedstock, its thermodynamic stability necessitates the development of highly efficient catalysts that are able to promote chemical reactions under mild conditions. In this work, a novel mesoporous poly(ionic liquid) with dual active sites was synthesized through a facile method that involves co-polymerization, post-synthetic metalation, and supercritical CO2 drying. Due to a high density of nucleophilic and electrophilic sites, the as-prepared poly(ionic liquid), denoted as P2D-4BrBQA-Zn, offers excellent performance in a CO2 cycloaddition reaction using epichlorohydrin as the substrate (98.9% conversion and 96.9% selectivity). Moreover the reaction is carried out under mild, solvent-free, and additive-free conditions. Notably, P2D-4BrBQA-Zn also efficiently promotes the conversion of various other epoxide substrates into cyclic carbonates. Overall, the catalyst is found to have excellent substrate compatibility, stability, and recyclability.

In this article, we present a multiagent framework for real-time large-scale 3-D reconstruction applications. In SLAM, researchers usually build and update a 3-D map after applying nonlinear pose graph optimization techniques. Moreover, many multiagent systems are prevalently using odometry information from additional sensors. These methods generally involve extensive computer vision algorithms and are tightly coupled with various sensors. We develop a generic method for the key challenging scenarios in multiagent 3-D mapping based on different camera systems. The proposed framework performs actively in terms of localizing each agent after the first loop closure between them. It is shown that the proposed system only uses monocular cameras to yield real-time multiagent large-scale localization and 3-D global mapping. Based on the initial matching, our system can calculate the optimal scale difference between multiple 3-D maps and then estimate an accurate relative pose transformation for large-scale global mapping.

Ferritin nanoparticles with self-assembling properties have been widely explored as vaccine carrier by displaying foreign antigens through genetic fusion strategy. In the present work, an apoferritin (AFt) nanoparticle was tested as influenza vaccine carrier by chemically conjugating a matrix protein 2 ectodomain (M2e) antigen peptide or/and the full-length hemagglutinin (HA) antigen on the outer surface of the AFt, with heterobifunctional sSMCC or SM(PEG)24 containing PEG chain as linkers. To each AFt nanoparticle, about 30-32 M2e or 1.8 HA antigen could be coupled. The AFt-(PEG)24-M2e, in which the M2e was coupled through SM(PEG)24 containing PEG chain, conferred higher protective efficacy in immunized mice than AFt-M2e did, but was less effective than AFt-(PEG)24-HA. When both M2e and HA were coupled, the synthesized dual-antigen vaccine candidate AFt-(PEG)24-M2e/HA elicited high level of M2e and HA antigen-specific antibodies and conferred 100% protection against lethal infection of homologous PR8 H1N1 virus strain and 70% protection against a heterologous A/FM/1/47 (FM1, H1N1) strain, which was more effective than the M2e or HA single antigen vaccine candidates. The potential cross-protective effect of the dual-antigen vaccine was further demonstrated by significant specific hemagglutination inhibition (HAI) titers in serum of the immunized mice against three other heterologous viral strains including A/Singapore/GP1908/2015 (IVR-180) H1N1, A/Anhui/1/2005 H5N1, and A/Hong Kong H3N2.

Indole-3-carbinol (I3C), an important anticancer compound found in broccoli, has attracted considerable attention. The rapid extraction and accurate analysis of I3C in the pharmaceutical industry in broccoli is challenging as I3C is unstable at low pH and high temperature. In this study, a rapid, accurate, and low-cost ultrasound-assisted dispersive-filter extraction (UADFE) technique based on poly(deep eutectic solvent)-graphene oxide (PDES-GO) adsorbent was developed for the isolation and analysis of I3C in broccoli for the first time. PDES-GO with multiple adsorption interactions and a fast mass transfer rate was synthesized to accelerate adsorption and desorption. UADFE was developed by combining dispersive solid-phase extraction (DSPE) and filter solid-phase extraction (FSPE) to realize rapid extraction and separation. Based on the above two strategies, the proposed PDES-GO-UADFE method coupled with high-performance liquid chromatography (HPLC) allowed the rapid (15–16 min), accurate (84.3–96.4%), and low-cost (adsorbent: 3.00 mg) analysis of I3C in broccoli and was superior to solid-phase extraction, DSPE, and FSPE methods. The proposed method showed remarkable linearity (r=0.9998; region: 0.0840–48.0 μg/g), low limit of quantification (0.0840 μg/g), and high precision (relative standard deviation ≤ 5.6%). Therefore, the PDES-GO-UADFE-HPLC method shows significant potential in the field of pharmaceutical analysis for the separation and analysis of anti-cancer compounds in complex plant samples.

The characterization of the protein corona has become an essential part of understanding the biological properties of nanomaterials. This is also important in the case of mesoporous silica particles intended for use as drug delivery excipients. A combination of scattering, imaging and protein characterization techniques is used here to assess the effect of particle shape and growth of the reversible (soft) and strongly bound (hard) corona of three types mesoporous silica particles with different aspect ratios. Notable differences in the protein composition, surface coverage and particle agglomeration of the protein corona-particle complex point to specific protein adsorption profiles highly dependent on exposed facets and aspect ratio. Spherical particles form relatively homogeneous soft and hard protein coronas (approx.10 nm thick) with higher albumin content. In contrast to rod-shaped and faceted particles, which possess soft coronas weakly bound to the external surface and influenced to a greater extent by the particle morphology. These differences are likely important contributors to observed changes in biological properties, such as cell viability and immunological behaviour, with mesoporous silica particle shape.

An interaction function was constructed based on the axial compression/tension and shear loads of orthotropic plates. The coefficients of the polynomial function were determined by uniaxial test results. Buckling interaction and failure interaction formulae under combined axial tension/compression and shear loads were established. Based on the uniaxial load test results of orthotropic plates, the buckling load and bearing capacity under any proportion of the combined loads could be predicted by using the proposed interaction formulae. The buckling interaction curves and failure envelopes predicted by the proposed interaction formulae were in excellent agreement with the test results.

Herein, sodium dodecylbenzene sulfonate (SDBS) was used as a template to control the synthesis of Ca0.5Pr0.5FeO3. Its microstructure, composition, and morphology were detected via X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM). The properties of catalyzing bagasse lignin (BL) pyrolysis were determined by thermogravimetric analysis (TG) test and evaluation of a fixed bed alumina microreactor. The results show that the sample Ca0.5Pr0.5FeO3 regulated by SDBS has a cubic crystal phase, and the addition of SDBS does not cause phase transition. Moreover, when the SDBS concentration is 0.10 mol/L, the particle size is 200–500 nm and the specific surface area is 11.26 m2/g. The yields of gas, liquid, and solid products in the BL catalytic pyrolysis are 39.58 wt%, 26.76 wt% and 32.36 wt%, respectively. The contents of CO2 and CO decrease from 54.07% and 4.98% to 45.29% and 3.23%, respectively. The liquid products are mainly guaiacol, syringol, and phenol, and the total selectivity of phenols is 83.67%, accompanied by a small amount of non-aromatic oxygen-containing compounds (five-membered ring (furan) or ester). Compared with the BL pyrolysis and Ca0.5Pr0.5FeO3 catalytic pyrolysis products, the selectivity of guaiacol compounds increases by 43.26%, while those of syringol compounds and phenylketones decrease by 30.08% and 3.39%, respectively. The selectivity of 2,6-dimethoxyphenol is 28.37%. After five catalytic pyrolysis-regeneration cycles, the characteristic peaks of the catalyst do not change significantly and the particles are uniform, suggesting that the catalyst has good crystal phase stability and regeneration stability.

Flexible narrowband near infrared (NIR) photodetectors (PDs) are urgently in demand in the fast-developing era of flexible electronics, due to their crucial roles in various innovative applications. Hence, we designed and synthesized the core–shell structured NaYF4:Yb3+,Er3+@NaYF4:Nd3+ upconversion nanoparticles (UCNPs), which can be pumped by the 808 and 980 nm lights. The upconversion luminescence (UCL) are significantly enhanced after being assembled with the opal photonic crystals (OPCs) due to the photonic crystal effect, with 55 and 48 folds of enhancement factors under illuminations of 808 and 980 nm lights, respectively. Based on this hybrid, the flexible narrowband PDs were successfully fabricated on the PET substrate with the structure of OPCs/NaYF4:Yb3+,Er3+@Nd3+/MAPbI3, which displays excellent detection performance to double narrowband NIR light (808 and 980 nm) benefiting from the amplified UCL, with responsivity of 8.79 and 7.39 A/W, detectivity of 3.01 × 1011 and 2.68 × 1011 cm⋅Hz1/2/ W for 808 and 980 nm lights detection respectively, along with short response time in the range of 120–160 ms. Furthermore, the OPCs/NaYF4:Yb3+,Er3+@NaYF4:Nd3+/MAPbI3 double narrowband PDs display low photodetection power threshold (0.05 W/cm2), outstanding flexibility, prominent moisture resistance, and good long-time stability. This work displays a new concept of narrowband NIR PDs, which open a new field for specific NIR light detections.

In order to improve the red luminescent properties, Sr2MgSi2O7:Eu2+,Dy3+ was selected as a blue persistent luminescent donor phosphor, while light conversion agent was utilized to tune the persistent luminescent spectra from blue to red. Composite red luminescent material Sr2MgSi2O7:Eu2+,Dy3+/light conversion agent (SMED/LCA) was fabricated with light conversion agent and Sr2MgSi2O7:Eu2+,Dy3+ at a certain mass ratio. SiO2 (Al2O3 or MgF2) were coated on the surface of SMED/LCA through heterogeneous deposition method. The structural and optical characteristics of the resulting samples were launched in terms of X-ray diffraction and emission spectrum as well as afterglow brightness. The results demonstrate that the emission spectrum exhibits two emission bands, and the peaks are located at around 470 and 615 nm. SiO2, Al2O3 and MgF2 are coated on the surface of SMED/LCA like a protective shell to maintain its stability and luminescent properties, the afterglow initial brightness is still up to 0.37 cd/m2 and the afterglow color purity calculated from CIE color coordinates is basically unchanged.

The research and exploration of manganese-based aqueous zinc-ion batteries have been controversial of cycle stability and mechanism investigation, thus improving the stability and exploring storage mechanism are still the most main issue. Defect engineering has become an effective method to improve cycle stability. Herein, a nitrogen-doped e-MnO2 (MnO2@N) has been prepared using electrochemical deposition and heat treatment under nitrogen atmosphere. As the cathode for zinc-ion batteries, the capacity retention rate of MnO2@N cathode is close to 100% after 500 cycles at 0.5 A g−1, while the capacity retention rate for the initial MnO2 cathode is 62%. At 5 A g−1, the capacity retention rate of MnO2@N cathode is 83% after 1000 cycles, which is much higher than the 27% capacity retention rate for the original MnO2 cathode. And it can be found that the oxygen vacancies increase after nitrogen doping, which can improve the conductivity of the MnO2@N cathode. Also, there is Mn-N bond in MnO2@N, which can enhance the electrochemical stability of MnO2@N cathode. In addition, the electrochemical mechanism of MnO2@N cathode has been explored by the CV, GCD and GITT tests. It is found that nitrogen doping promotes the intercalation of H+ and the corresponding capacity contribution. Compared with the original MnO2 cathode, the diffusion coefficient of H+ and Zn2+in MnO2@N cathode increases. Also, the reactions during the charging and discharging process are explored through the ex-situ XRD test. And this work may provide some new ideas for improving the stability of manganese-based zinc-ion batteries.

Transitional metal selenides have high conductivity, even metal quality, which makes them great for using as electrode materials for fabricating supercapacitors. Here, hierarchical Ni3Se2 nanosheet-on-nanorods on Ni foam (NSR-Ni3Se2/Ni) was fabricated by a facile three-dimensional (3D) substrate-assisted confinement assembly method, and used as a freestanding electrode material for hybrid supercapacitors (HSCs). In this design, metallic Ni3Se2 with hybrid 1D/2D architecture could effectively enhance the active specific surface area of electrode and improve space utilization, as well as significantly facilitate electrons transport, while Ni foam served as the Ni source of Ni3Se2 and provided 3D multi-electron transport channels, thus boosting the specific capacity. The constructed hierarchical NSR-Ni3Se2 electrode delivered a superior areal specific capacity of 1.068 mAh/cm2 (7.69 F/cm2) at 2 mA/cm2 and retained 68.2% of the initial capacity when the current density increases by 15 times. Furthermore, the as-assembled NSR-Ni3Se2 device exhibited an ultrahigh energy density of 56.4 Wh/kg and high power density of 4640.3 W/kg, and a capacity retention of 92.6% even after 6000 cycles.

In this work, we used the selective laser melting (SLM) fabricated Co-Cr alloy with prominent residual strain, extremely non-equilibrium microstructures, and low stacking fault energy as a precursor to fabricate materials with the optimal grain boundary character distribution. The grain boundary engineering (GBE) of the Co-Cr alloy was achieved by a simple heat treatment of the SLM-fabricated Co-Cr alloy. The obtained GBE Co-Cr alloy exhibited 81.47% of special grain boundaries (Σ3n n = 1, 2, 3)), while it substantially disrupted the connectivity of the random high-angle boundaries, successfully reducing the propensity of intergranular degradation. Slow strain rate tests (SSRTs) showed that the GBE Co-Cr alloy possessed lower stress corrosion cracking (SCC) susceptibility and higher ductility in the corrosive environment (0.9% NaCl solution) than in the air. The high fraction of special boundaries, coupled with the stress-induced martensitic transformation (SIMT) in the GBE Co-Cr alloy yielded these results, which unique and rarely simultaneously satisfied for common structural materials. The current “SLM induced GBE strategy” offers a novel approach towards customized GBE materials with high SCC resistance and ductility in the corrosive environment, shedding new light on developing high-performance structural materials.

Antibiotic resistanceand biofilm formation are the main challenges of bacterial infectious diseases, and enhancing the permeability of drugs to biofilms may be a promising strategy. Herein, we constructed a cationic chitosan coated ruthenium dioxide nanozyme (QCS-RuO2@RBT, SRT NSs)。RuO2 nanosheets (RuO2 NSs) are modified with positively charged Quaternary ammonium-chitosan (QCS) to improve biocompatibility, and enhance the interaction between RuO2 nanozymes and bacterial membranes. An antibacterial drug, [Ru(bpy)2(tip)]2+ (RBT) can be loaded onto QCS-RuO2 by π-π stacking and hydrophobic interaction. SRT NSs exhibit NIR light enhanced peroxidase-like catalytic activity, thereby effectively fighting against planktonic bacteria and damaging biofilms. In the biofilm, extracellular DNA (eDNA) was cleaved by high levels of hydroxyl radicals (•OH) catalyzed by SRT NSs, thereby disrupting the rigid biofilm. In addition, in vivo studies demonstrate that SRT NSs can significantly rescue skin wound infections and the chronic lung infection in mice caused by P. aeruginosa, and hold the same therapeutic efficacy as first-line clinically anchored anti P. aeruginosa drug ciprofloxacin. Accordingly, the research work has realized the efficient production of ·OH, and the permeability of drugs to biofilms.it provides a promising response strategy for the management of biofilm-associated infections, including chronic lung infection.

Neural network (NN) computing contains a large number of multiply-and-accumulate (MAC) operations. The performance of NN accelerator is limited with the traditional von Neumann architecture due to the tremendous off-chip memory accesses. Resistive random-access memory (ReRAM)-based crossbars can naturally perform matrix–vector multiplication (MVM) operations and are well suitable for NN accelerators. In the existing ReRAM-based NN accelerators, the synaptic weights represented by the conductances of ReRAMs are mainly based on the binary coding. However, the imperfect fabrication process combined with stochastic filament-based switching leads to resistance variations of ReRAMs, which can significantly alter the weights in binary synapses and degrade the NN accuracy. Moreover, the NN accuracy further deteriorates with multilevel cells (MLCs) used for reducing hardware overhead. In this article, a novel unary coding of synaptic weights is proposed to overcome the resistance variations of MLCs and achieve reliable ReRAM-based neuromorphic computing. A variation-aware optimal mapping scheme is also proposed in compliance with the unary coding to guarantee high accuracy by leveraging a unique feature of unary coding—the existence of multiple ways to represent the same value. The optimal mapping obtains very small errors for weights with resistance variations of MLCs. Our simulation results show that under resistance variations, the proposed method achieves less than 0.08% and 3.43% accuracy loss on CIFAR10 and ImageNet, respectively, compared to the ideal accuracy. With each synaptic weight represented by four 2-b MLCs, the proposed method improves the accuracy over the traditional binary coding scheme by 83.39% and 87.6% for CIFAR10 and ImageNet, respectively.

The existing signcryption schemes with equality testing are aimed at a sole cryptosystem and not suitable for the sophisticated heterogeneous network of Industrial Internet of Things (IIoT). To deal with this challenge, we propose a heterogeneous signcryption scheme with equality test (HSC-ET) in this article. This scheme enables a sensor in public key infrastructure (PKI) to execute data encryption and deliver it to the semitrusted entity (cloud server). When a user in an identity-based cryptosystem (IBC) intends to search for some data stored on the cloud server. The delegated cloud server executes tests on ciphertexts for determining whether the same underlying plaintext exists between two ciphertexts. These two ciphertexts can be one signcrypted ciphertext and one encrypted ciphertext, or both encrypted/signcrypted ciphertext, thus achieving a flexible search to the ciphertext. HSC-ET is demonstrated to be secure by the rigorous and detailed analysis. The experimental simulation and analysis results show the efficiency of our scheme.

Series and parallel two-stage evaporative strategy for vapor compression refrigeration cycles characterized by temperature and humidity independent control were presented. The theoretical model was established to analyze the performance of parallel two-stage evaporative strategy regarding the coefficient of performance (COP), exergy loss, exergy efficiency in comparisons with series system. And refrigerants R290 and R600 with low global warming potential (GWP) and no ozone depletion potential (ODP) are proposed as alternative refrigerants for R134a in two systems. The results show that compared with R134a, the proposed R600 has better performance with higher specific refrigerating capacity and coefficient of performance, of which specific refrigerating capacity increase 102.72% than that of R134a on average. Series two-stage evaporative strategy for vapor compression refrigeration cycle with R600 had the optimal techno-economic performance, which COP and exergy efficiency are 7.8% and 11% higher than that of parallel two-stage evaporative strategy, respectively.

The ongoing deployment of 5G network involves the Internet of Things (IoT) as a new technology for the development of mobile communication, where the Internet of Everything (IoE) as the expansion of IoT has catalyzed the explosion of data and can trigger new eras. However, the fundamental and key component of the IoE depends on the computational intelligence (CI), which may be utilized in the sixth generation mobile communication system (6G). The motivation of this article presents the 6G enabled network in box (NIB) architecture as a powerful integrated solution that can support comprehensive network management and operations. The 6G enabled NIB can be used as an alternative method to meet the needs of next-generation mobile networks by dynamically reconfiguring the deployment of network functions, providing a high degree of flexibility for connection services in various situations. Especially the CI technology such as evolutionary computing, neural computing and fuzzy systems utilized as a part of NIB have inherent capabilities to handle various uncertainties, which have unique advantages in processing the variability and diversity of large amounts of data. Finally, CI technology for NIB, which is widely used is also introduced such as distributed computing, fog computing, and mobile edge computing in order to achieve different levels of sustainable computing infrastructure. This article discusses the key technologies, advantages, industrial scenario applications of CI technology as NIB, typical use cases and development trends based on IoE, which provides directional guidance for the development of CI technology as NIB for 6G.

Peripheral nerve regeneration requires stepwise and well-organized establishment of microenvironment. Since local delivery of VEGF-A in peripheral nerve repair is expected to promote angiogenesis in the microenvironment and Schwann cells (SCs) play critical role in nerve repair, combination of VEGF and Schwann cells may lead to efficient peripheral nerve regeneration. VEGF-A overexpressing Schwann cells were established and loaded into the inner wall of hydroxyethyl cellulose/soy protein isolate/polyaniline sponge (HSPS) conduits. When HSPS is mechanically distorted, it still has high durability of strain strength, thus, can accommodate unexpected strain of nerve tissues in motion. A 10 mm nerve defect rat model was used to test the repair performance of the HSPS-SC (VEGF) conduits, meanwhile the HSPS, HSPS-SC, HSPS-VEGF conduits and autografts were worked as controls. The immunofluorescent co-staining of GFP/VEGF-A, Ki67 and MBP showed that the VEGF-A overexpressing Schwann cells could promote the proliferation, migration and differentiation of Schwann cells as the VEGF-A was secreted from the VEGF-A overexpressing Schwann cells. The nerve repair performance of the multifunctional and flexible conduits was examined though rat behavioristics, electrophysiology, nerve innervation to gastrocnemius muscle (GM), toluidine blue (TB) staining, transmission electron microscopy (TEM) and NF200/S100 double staining in the regenerated nerve. The results displayed that the effects on the repair of peripheral nerves in HSPS-SC (VEGF) group was the best among the conduits groups and closed to autografts. HSPS-SC (VEGF) group exhibited notably increased CD31+ endothelial cells and activation of VEGFR2/ERK signaling pathway in the regenerated nerve tissues, which probably contributed to the improved nerve regeneration. Altogether, the comprehensive strategy including VEGF overexpressing Schwann cells-mediated and HSPS conduit-guided peripheral nerve repair provides a new avenue for nerve tissue engineering., Graphical abstract Image 1, Highlights • A flexible and conductive HSPS conduits was fabricated. • The endogenous VEGF-A secretion HSPS conduit was successfully constructed. • HSPS conduits, Schwann cells and VEGF-A synergistically promote nerve regeneration. • VEGFR2/ERK signal pathway may play critical role in nerve regeneration.

The effect of the high magnetic field (MF) on the distribution of solute concentration during directional solidification of Al-Cu alloy under low growth speed was experimentally investigated. The amount of non-equilibrium eutectic is quantified via X-ray computed tomography (XCT) and demonstrated to reduce with the application of MF. Further, experimental results reveal that the MF alleviates the microsegregation and increases the average Cu concentration in solid solution, leading to the increases of the effective partition coefficient k e . It was also found that Cu concentration in solid solution increases continuously with the increasing intensity of MF, following the strengthening of micro-hardness. The change of k e under the MF is demonstrated to attribute to the thermoelectric magnetic convection (TEMC) in the mushy zone and the thermoelectric magnetic force (TEMF) acting on the solid. The TEMC is supposed to cause secondary convection owing to the inequality in flow velocities of circulation in different positions of dendrite stem. And the vacancies created by the proliferation and movement of dislocations induced by TEMF in the matrix is supposed to be able to capture solute atoms and thus enhance the solute concentration in the solid solution.

Durability is one of the critical issues to restrict the commercialization of proton exchange membrane fuel cells (PEMFCs) for the vehicle application. The practical dynamic operation significantly affects the PEMFCs durability by corroding its key components. In this work, the degradation behavior of a single PEMFC has been investigated under a simulated automotive load-cycling operation, with the aim of revealing the effect of load amplitude (0.8 and 0.2 A/cm2 amplitude for the current density range of 0.1−0.9 and 0.1−0.3 A/cm2, respectively) on its performance degradation. A more severe degradation on the fuel cell performance is observed under a higher load amplitude of 0.8 A/cm2 cycling operation, with ∼10.5% decrease of cell voltage at a current density of 1.0 A/cm2. The larger loss of fuel cell performance under the higher load amplitude test is mainly due to the frequent fluctuation of a wider potential cycling. Physicochemical characterizations analyses indicate that the Pt nanoparticles in cathodic catalyst layer grow faster with a higher increase extent of particle size under this circumstance because of their repeated oxidation/reduction and subsequent dissolution/agglomeration process, resulting in the degradation of platinum catalyst and thus the cell performance. Additionally, the detected microstructure change of the cathodic catalyst layer also contributes to the performance failure that causes a distinct increase in mass transfer resistance.

Topological insulator has attracted worldwide attention due to its promising application prospects in magnetoresistive devices, optoelectronic devices, spintronic and quantum computing. Nevertheless, its potential in electrochemical energy storage have not been fully explored and utilized. In this paper, a composite of high conductive polypyrrole encapsulated Bi2Te3, a hexagonal phase topological insulator, was synthesized by one-step solvothermal method, and its electrochemical properties were extensively studied. Benefiting from the inherent characteristics of topological insulator, the effective polypyrrole coating, and the intrinsic large interplanar spacing within Bi2Te3, the obtained Bi2Te3@PPy composite exhibited high specific capacity, high-rate capability, and long-term cyclic stability compared with other Bi-based materials in sodium ion batteries system. Furthermore, the reaction mechanism of conversion combined with alloying for Bi2Te3@PPy was revealed by in-situ XRD and ex-situ TEM techniques. The DFT calculations shown that the sandwiching interlayer between Bi2Te3 and PPy would familiar to the Na+ transfer, and the narrowing band gap would enhance the conductivity of the system, which will not only help us to better understand the sodium storage mechanism and reaction kinetics of Bi2Te3, but also provides a reliable strategy for the development of topological insulator as sodium-ion batteries anode materials.

Constructing effective interphase boundary is one of the efficient approaches for improving photocatalytic performances of semiconductor materials. In this work, an anatase/rutile-TiO2 (AR-TiO2) heterophase junction with appropriate carbon content was successfully fabricated via an in-situ phase transformation process. The phase transformation started from the inner core of the nanoparticles and the area of phase interface between anatase and rutile was carefully controlled by regulating the activation temperature. The well-established type-II band alignment between two TiO2 phases with residual carbon as additional charge transfer intermediary which significantly improved the light-harvesting and photoinduced electron-hole pair separation. As a result, the optimal AR-TiO2-550 catalyst (without adding commonly used Pt as co-catalyst) remarkably enhanced photocatalytic H2 generation (201 μmol h−1 g−1), which was about 12-fold to that of P25. The AR-TiO2-550 heterophase junction also showed long-term stability under simulated solar light irradiation. This research provides a new phase engineering route for developing high-efficient photocatalysts.

Layer-structured SnSSe attracts much attention as an anode material for potassium storage due to its large theoretical capacity. Unfortunately, their practical application is severely restrained by the dramatic volumetric variation of SnSSe. Herein, we synthesize ultrafine SnSSe/multilayer graphene nanosheet (SnSSe/MGS) by a vacuum solid-phase reaction and subsequent ball milling. Owing to the strong synergistic effect between the two components, the obtained SnSSe/MGS nanocomposite exhibits a high reversible capacity (423 mAh g−1 at 100 mA g−1), excellent rate property (218 mAh g−1 at 5 A g−1), and stable cycling performance (271 mAh g−1 after 500 cycles at 100 mA g−1) in potassium-ion half batteries. Moreover, the full cell assembled by the SnSSe/MGS anode and the potassiated 3,4,9,10-perylene-tetracarboxylic aciddianhydride cathode shows excellent electrochemical performance between 0.2 and 3.3 V (209 mAh g−1 at 50 mA g−1 after 100 cycles). The presented two-step synthesis strategy of SnSSe/MGS may also provide ideas to craft other alloy-type anode materials.

In this paper, we propose a hybrid framework using visual and force sensing for human-robot co-carrying tasks. Visual sensing is utilized to obtain human motion and an observer is designed for estimating control input of human, which generates robot's desired motion towards human's intended motion. An adaptive impedance-based control strategy is proposed for trajectory tracking with neural networks (NNs) used to compensate for uncertainties in robot's dynamics. Motion synchronization is achieved and this approach yields a stable and efficient interaction behavior between human and robot, decreases human control effort and avoids interference to human during the interaction. The proposed framework is validated by a co-carrying task in simulations and experiments.

RGB-D salient object detection aims at identifying attractive objects in a scene by combining the color image and depth map. However, due to the differences between RGB-D image pairs, it is a key issue to utilize cross-modal data effectively. In this paper, we propose a novel RGB-D salient object detection method via cross-modal joint feature extraction and low-bound fusion loss. A two-stream framework is designed to generate the saliency maps for the RGB image and depth map. During the feature extraction, a cross-modal joint feature extraction module (CFM) is proposed to capture valuable joint features from the two streams. The CFM explores complementary information from the feature extraction and feeds the joint features to the aggregation stage of the network. Then, the fusion block (FB) is utilized to aggregate the multi-scale features of each stream and the joint features to generate the updated features. In addition, a low-bound fusion loss is designed to constrain the predictions of the two streams, to improve the lower bound of saliency values and generate a distinct saliency map. Experimental results on five datasets demonstrate that the proposed method achieves superior performances.

In order to fully utilize the advantages that one-dimensional (1D) materials are conducive to form a conductive network and surface wrinkled microspheres can cause multiple reflection. In this paper, two MXene-based magnetic composites have been innovatively fabricated. 1D MXene@Fe3O4 magnetic nanofibers with a diameter of 25 nm are obtained by the self-assembly of single-layer Ti3C2Tx MXene nanosheets and coating Fe3O4 nanoparticles via thermal decomposition method. The micro-scale surface wrinkled porous MXene@Fe3O4 composite microspheres are prepared by simple ultrasonic atomization technology. A high efficiency microwave absorbing system is obtained by blending these two composites. Through the evaluation of microwave absorption performance, the optimal ratio of composite microspheres and nanofibers is conformed to be 7:3. The minimum reflection loss (RLmin) is −63.3 dB at a filler content of 40%. The corresponding matching thickness is 1.8 mm. The maximum effective absorption bandwidth (EABmax) is 5.2 GHz (12.8–18 GHz). Microwave absorbing mechanism study shows that the attenuation approaches include dielectric loss, magnetic loss, multiple reflection and conductive loss from the unique structure and impedance matching.

Osmotic heat engine (OHE) is a promising technology to harvest low-grade heat from renewable energy source. In previous studies of OHEs, the features of actual heat source and application scenarios are usually ignored. Here we present an advanced adsorption-based osmotic heat engine to harvest solar energy and a dynamic model for such energy utilization system is established. Firstly, the dynamic characteristics of the OHE from transient to cyclic-steady state is investigated. There exist an optimal adsorption/desorption time to maximize the electric power and efficiency simultaneously. Higher working concentration elevates the electric power and efficiency. Larger direct solar irradiation intensity upgrades the electric power while hinders the efficiency. Then a practical simulation of a small sized OHE harvesting solar energy to generate electricity during a day is carried out and the effects of some important parameters on the system under transient state are analyzed. The results indicate that there is a best number of cycles the system performs during a day to maximize the average electric power and efficiency. Among the ten selected adsorbents, MIL-101 leads to the largest average electric power of 41.8 W and Zeolite 13X leads to the highest electric efficiency of 1.04% when the number of cycles is set as 60 and 7 mol/kg NaCl is employed as working solution.

The development of low-price and highly efficient catalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) has always been challenging with regard to water splitting. Pyrrhotite Fe7S8 has become a research hotspot due to its abundant reserves, high electrical conductivity and excellent catalytic activity. In general, introducing metal heteroatoms into transition metal sulfides (TMSs) can effectively enhance the activity and stability of TMSs. Herein, Co-doped pyrrhotite Fe7S8 nanosheets were obtained by a straightforward two-step method consisting of hydrothermal treatment followed by subsequent heat treatment. Results from XPS analysis and contact angle measurements showed that doping optimized the chemical environment around iron atoms and enhanced the adsorption of water molecules on the surface of Fe7S8, thereby greatly improving the electrocatalytic efficiency of water electrolysis. Compared with other counterparts, Co0·95Fe6·05S8 exhibited superior OER activity with an overpotential of 311 mV at a current density of 10 mA cm−2, and higher performance towards HER with an overpotential of 284 mV at 10 mA cm−2 in alkaline solution. In sum, Co0·95Fe6·05S8 is promising as a bifunctional catalyst for water splitting under alkaline conditions.

Electrochemical oxidation of water to produce highly reactive hydroxyl radicals ( OH) is the dominant factor that accounts for the organic compounds removal efficiency in water treatment. As an emerging carbon-based material, the investigation of electrocatalytic of water to produce OH on Graphdiyne (GDY) anode is firstly evaluated by using first-principles calculations. The theoretical calculation results demonstrated that the GDY anode owns a large oxygen evolution reaction (OER) overpotential (ηOER = 1.95 V) and a weak sorptive ability towards oxygen evolution intermediates (HO*, not OH). The high Gibbs energy change of HO* (3.18 eV) on GDY anode makes the selective production of OH (ΔG = 2.4 eV) thermodynamically favorable. The investigation comprises the understanding of the relationship between OER to electrochemical advanced oxidation process (EAOP), and give a proof-of-concept of finding the novel and robust environmental EAOP anode at quantum chemistry level.

This article discusses the various blood interactions that may occur with various types of nano drug-loading systems. Nanoparticles enter the blood circulation as foreign objects. On the one hand, they may cause a series of inflammatory reactions and immune reactions, resulting in the rapid elimination of immune cells and the reticuloendothelial system, affecting their durability in the blood circulation. On the other hand, the premise of the drug-carrying system to play a therapeutic role depends on whether they cause coagulation and platelet activation, the absence of hemolysis and the elimination of immune cells. For different forms of nano drug-carrying systems, we can find the characteristics, elements and coping strategies of adverse blood reactions that we can find in previous researches. These adverse reactions may include destruction of blood cells, abnormal coagulation system, abnormal effects of plasma proteins, abnormal blood cell behavior, adverse immune and inflammatory reactions, and excessive vascular stimulation. In order to provide help for future research and formulation work on the blood compatibility of nano drug carriers., Graphical abstract Image, graphical abstract

In this work, Cf/(Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)C-SiC high-entropy ceramic matrix composites were reported for the first time. Based on the systematic study of the pyrolysis and solid-solution mechanisms of (Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)C precursor by Fourier transform infrared spectroscopy, TG-MS and XRD, Cf/(Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)C-SiC with uniform phase and element distribution were successfully fabricated by precursor infiltration and pyrolysis. The as-fabricated composites have a density and open porosity of 2.40 g/cm3 and 13.32 vol% respectively, with outstanding bending strength (322 MPa) and fracture toughness (8.24 MPa m1/2). The Cf/(Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)C-SiC composites also present excellent ablation resistant property at a heat flux density of 5 MW/m2, with linear and mass recession rates of 2.89 μm/s and 2.60 mg/s respectively. The excellent combinations of mechanical and ablation resistant properties make the Cf/(Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)C-SiC composites a new generation of reliable ultra-high temperature materials.

The present study develops a novel energy system comprising a double-flash based geothermal cycle, a solar-driven cycle, a polymer electrolyte membrane (PEM) system and a waste heat recovery system. The proposed system can be used to generate electricity, produce hydrogen, space heating and prepare domestic hot water, and the solar-driven cycle can be turned off as a double-flash geothermal system when there is no solar radiation and the storage is empty. The unique aspect of the proposed system lies in the coupling relationship between the three turbine units in clear weather. Energy and exergy analyses are carried out to determine the irreversibilities, show the performance of the system and compare it with sole geothermal system. The results show that the proposed system has satisfactory thermodynamic properties. Under the reference conditions, the proposed energy system has a 148.3% (from 6171 kW to 15321 kW) increase in power generation compared with a sole double-flash geothermal system; under the optimal working conditions, the energy efficiency and exergy efficiency of the system can reach 29.6% and 29.2%, respectively. Furthermore, the effect of changing various system parameters on the energy and exergy efficiencies of the entire system and its subsystems were also studied.

Purpose The purpose of this paper is to study an electrolytic etching method to prepare fine lines on printed circuit board (PCB). And the influence of organics on the side corrosion protection of PCB fine lines during electrolytic etching is studied in detail. Design/methodology/approach In this paper, the etching factor of PCB fine lines produced by new method and the traditional method was analyzed by the metallographic microscope. In addition, field emission scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) were used to study the inhibition of undercut of the four organometallic corrosion inhibitors with 2,5-dimercapto-1,3,4-thiadiazole, benzotriazole, l-phenylalanine and l-tryptophan in the electrolytic etching process. Findings The SEM results show that corrosion inhibitors can greatly inhibit undercut of PCB fine lines during electrolytic etching process. XPS results indicate that N and S atoms on corrosion inhibitors can form covalent bonds with copper during electrolytic etching process, which can be adsorbed on sidewall of PCB fine lines to form a dense protective film, thereby inhibiting undercut of PCB fine lines. Quantum chemical calculations show that four corrosion inhibitor molecules tend to be parallel to copper surface and adsorb on copper surface in an optimal form. COMSOL Multiphysics simulation revealed that there is a significant difference in the amount of corrosion inhibitor adsorbed on sidewall of the fine line and the etching area. Originality/value As a clean production technology, electrolytic etching method has a good development indicator for the production of high-quality fine lines in PCB industry in the future. And it is of great significance in saving resources and reducing environmental pollution.

The effect of butyrate on hydrogen production and the potential mechanism were investigated by adding butyric acid into dark fermentative hydrogen production system at different concentrations at pH range of 5.5–7.0. The results showed that under all the tested pH from 5.5 to 7.0, the addition of butyric acid can inhibit the hydrogen production, and the inhibitory degree (from 10.5% to 100%) increased with the increase of butyric acid concentration and with the decrease of pH values, which suggested that the inhibition effect is highly associated with the concentration of undissociated acids. Substrate utilization rate and VFAs accumulation also decreased with the addition of butyric acid. The microbial community analysis revealed that butyrate addition can decrease the dominant position of hydrogen-producing microorganisms, such as Clostridium, and increase the proportion of other non-hydrogen-producing bacteria, including Pseudomonas, Klebsiella, Acinetobacter, and Bacillus.

Concentrated photovoltaic (CPV) has been identified as an effective method to further enhance the efficiency of photovoltaic cells. Previous studies on CPV mainly focused on III-V multi-junction cells. Nevertheless, III-V CPV technology is mainly used in niche applications due to its high cost. Here, we use metal-halide perovskite solar cell (PSC) to demonstrate a concentrated photovoltaic-thermoelectric tandem device. The thermoelectric generator (TEG) is utilized to reduce the effect of heat generation under concentrated solar irradiance. Our tandem system achieved a peak power conversion efficiency (PCE) of 25.0% at a solar concentration of 3 suns. This efficiency exceeded that of the single PSC by ~4.7%. Our work proves that by controlling the heat flow in concentrated PSC-TEG tandem system, the redundant heat produced by upper PSC can be effectively reused. This tandem structure provides a promising approach to improve the efficiency and stability of PSC under low-concentrated solar irradiation.

Acute kidney injury (AKI), a major health issue concerning ~50% of patients treated in intensive care units, generally leads to severe renal damage associated with high mortality rate. The application of nanotechnology for the management of AKI has profound potential of further development, providing innovative strategies for predicting the early onset and progression of renal disease and improving the treatment efficacy of the life-threating AKI. This review has comprehensively summarized the nanomedicines in the application of AKI diagnosis and emphatically discussed the unique potential of various nanotechnology-based drug delivery systems (e.g., polymeric nanoparticles, organic nanoparticles, inorganic nanoparticles, lipid-based nanoparticles, hydrogels etc.) in the treatment of AKI, allowing for improved therapeutic index by enhancing both efficacy and safety concurrently. These approaches may mechanically mitigate oxidative stress, inflammation, and mitochondrial and other organellar damage, etc. In addition, the combination of nanotechnology with stem cells-based therapy or gene therapy has been explored for reducing renal tissues damage and promoting kidney repair or recovery from AKI. The review provides insights into the synthesis, advantages, and limitations of innovative nanomedicine application in the early detection and effective treatment of AKI.

Lightweight and elastic carbon aerogels (CAs) are promising candidates for use in the development of pressure sensors and electromagnetic interference (EMI) shielding materials. However, the development of a simple strategy for the fabrication of CAs with the properties of high compression and excellent fatigue resistance is still significantly challenging. In this study, Pickering emulsion gel technology, which depends on the aqueous dispersion of cellulose nanofibrils (CNF), graphene oxide (GO), and 1, 2-dichloroethane solution of polymethyl methacrylate (PMMA) that occurs in mixture, emulsification, gelation, and freeze-drying process, was used to form a CNF-GO/PMMA composite aerogel. Subsequently, the final carbon aerogel (C-RGO/P) was obtained through annealing treatment. The resultant C-RGO/P exhibits super compressibility and excellent elasticity, and can resist an extreme compressive strain of 99.3% while maintaining 92.6% of the height retention after 5000 cycles at the strain of 80%. Additionally, it exhibits high sensitivity at the working pressure range of 0–1000 Pa, and can thus act as a wearable pressure sensor for the accurate monitoring of human physiological signals. Moreover, it can be used as an EMI shielding material with satisfactory EMI shielding effectiveness (SE) of 36.75 dB and specific shielding effectiveness (SSE) of 29400 dB cm3 g−1.

Oxygen evolution and oxygen reduction are considered as essential processes in the energy conversion devices. The progress of cost-effective bifunctional catalysts has become a critical issue to be solved. Here, we report that Co(OH)2 @N-doped carbon (NC) was facilely synthesized through the impregnation strategy of metal-organic frameworks derived carbon and cobalt ions. N-doped carbon with porous structure and cobalt hydroxide nanosheets play a synergistic effect role, representing excellent catalytic performance toward oxygen evolution and reduction reactions. The obtained Co(OH)2@NC exhibits remarkable activity in terms of a lower overpotential of 330 mV@10 mA cm−2 for OER and a more positive half-wave potential (E1/2 = 0.84 V) for ORR in alkaline medium, outperforming IrO2 and Pt/C. Due to its superior bifunctional catalytic performance, Co(OH)2@NC catalyst is applied into a promising air electrode of Zn-air battery. This presented strategy of impregnation synthesis in this work provides a new design direction for practical electrochemical energy devices.

Compact spinning, as a new kind of spinning technology, has gained wide attention because of its great reduction in spinning triangle and yarn hairiness. In order to meet the demand of high-grade clothing, research on further improving the performance of compact spun yarn is the emphasis. Of all the existing compact spinning systems, the four-roller compact spinning with lattice apron is most widely used at present because of its low cost. Therefore, this paper aims to put forward a new kind of device to improve yarn performance for four-roller compact spinning systems. Related experiments have been done to verify the efficiency of the device, and the mechanism is analyzed by computational fluid dynamics. The numerical simulation shows that the device can change the direction of airflow and increase the velocity in the directions of transverse condensing and thickness. It is shown that the air damper is convenient to use and has potential applications in spinning compact yarns with better performance.

All-inorganic halide perovskite nanowires (NWs) are promising materials due to they have broad application prospects in the field of optoelectronics, with mixed-halide perovskite nanowires can change the optoelectronic properties by adjusting the halide ratio. Here, we experimentally investigated the two-process governed anion-exchange reaction in single-crystalline CsPbX3 micro- and nanowires. The critical parameters affecting the outcome of the reaction are identified as the reaction temperature, reaction time, and precursor concentrations. Upon examining the photoluminescence and morphology of the NWs, high-quality NWs were obtained by optimizing these critical parameters. The bandgap of the NWs can be tuned over the entire visible spectra (430–700 nm). In addition, photodetectors incorporating single NWs were fabricated, which demonstrated excellent responsivity under illumination. Our results expand the validity of liquid-phase anion exchange to the microscale, and lay the basis for liquid-processed optoelectronics and displays.

Structural lightweight optimization is one of the key themes to continuously improve vehicle performance. However, most of the studies so far have not considered reliability and manufacturing issues brought about by the uncertainty of tolerances in structural lightweight optimization. In this study, a reliability-based design for lightweight vehicle structures with uncertain manufacturing accuracy is proposed. This method can provide not only the optimal design variables but also the maximum allowable deviation range. The main design variables lacking sample information are regarded as interval variables and other design parameters as probabilistic values. A progressive reliability-based design with uncertain manufacturing accuracy is established for lightweight vehicle structures by employing the transformation method of the interval model and the decoupling strategy of the probabilistic model. Firstly, the general test function is used to analyze the accuracy and efficiency of the reliability decoupling method. Then, lightweight optimization models of a classic cantilever beam and two vehicle structures (parking robot frame, energy absorption box) are established respectively, and the effectiveness of the present optimization method is verified. The optimized design results show that the optimal variables and the corresponding maximum allowable deviation range under acceptable manufacturing requirements can be obtained. The requirements for manufacturing accuracy can be reduced by appropriately increasing the deviation range of the design variables, which may lead to a reduction in manufacturing cost. This study aims to provide feasible design options by optimizing lightweight structures considering uncertain manufacturing accuracy.

The adsorption of hydrogen (H2) molecules on MoS2 monolayers doped with Fe, Co, Ni, Ru, Rh, Pd, Os, Ir or Pt was calculated via first-principle density functional theory (DFT). The H2 was found to interact most strongly with the MoS2 doped with Os with a higher adsorption energy of −1.103 eV. Investigations of the adsorptions of two to five H2 molecules on Os-doped MoS2 monolayers indicate that there are at most four H2 interacting stably with the substrate with a promising average adsorption energy of −0.792 eV. Molecular dynamics simulations also confirmed that the four H2 molecules can still be reasonably adsorbed and stored on the Os-doped MoS2 monolayer with a comparable average adsorption energy of −0.713 eV at 300 K. This study indicates that MoS2 monolayer doped with Os is a promising substrate to interact strongly with H2 and can be applied to effectively store H2 at room temperature.

Plate-like Fe-rich intermetallic phases directly influence the mechanical properties of recycled Al alloys; thus, many attempts have been made to modify the morphology of these phases. Through synchrotron X-ray imaging and electron microscopy, the underlying nucleation and growth mechanisms of Fe-rich phases during the solidification of Al-5Ti-1B-modified Al-2Fe alloys were revealed in this study. The results showed that the Al-5Ti-1B grain refiner as well as the applied pressure both resulted in reduction of the size and number of primary Al3Fe phases and promoted the formation of eutectic Al6Fe phases. The tomography results demonstrated that Al-5Ti-1B changed the three-dimensional (3D) morphology of primary Fe-rich phases from rod-like to branched plate-like, while a reduction in their thickness and size was also observed. This was attributed to the fact that Ti-containing solutes in the melts inhibit the diffusion of Fe atoms and the Al3Fe twins produce re-entrant corner on the twin boundaries along the growth direction. Moreover, the TiB2 provides possible nucleation sites for Al6Fe phases. The nucleation mechanism of Fe-rich phases is discussed in terms of experimental observations and crystallography calculations. The decrease in the lattice mismatch between TiB2 and Al6Fe phases was suggested, which promoted the transformation of Al3Fe to Al6Fe phases.

In this paper, a generalized finite difference method (GFDM) is proposed to solve the elasticity interface problem. This method turns the original elasticity interface problem to be some coupled non-interface subproblems. A large sparse matrix can be yielded by those subproblems. Since this method makes the interface become a part of boundaries of subproblems, it can deal well with problems with complex geometrical interfaces. Moreover, this method can also deal well with the interface conditions with derivatives, because the GFDM uses a linear summation of nearby nodal values to express the derivatives of unknown variables. Numerical examples are provided to verify the accuracy and stability of the proposed method for elasticity interface problems. They show that the H1 error of the method has the almost same convergence rate as the L2error and the size of jumps in the interface conditions only has a little effect on the stability of the proposed method.

With the further development of deep rock mechanics engineering, such as the exploitation and utilization of geothermal resources, the exploitation of deep mineral resources, and the safe disposal of nuclear waste, the study of mechanical properties of deep high-temperature rock is gaining the attention of the researchers. However, not only the high temperature but also the cooling condition/method that will be used in the construction such as drilling cooling will also greatly affect the mechanical properties of the rock. In this paper, the mechanical behaviour and the evolution of the mechanical properties of the high-temperature (600°C–1,000°C) granite under different cooling methods are studied. The following conclusions can be obtained: (1) The peak stress of the granite decreases with the heating temperature. Compared with natural cooling, water cooling has a more significant effect on strength degradation. (2) The increase of the heating temperature increases the maximum axial strain of the granite. The water cooling method more greatly induces the maximum axial strain of granite than the natural cooling. The maximum axial strain of the specimen under the water cooling reaches 117.3% of that under natural cooling (800°C). (3) The elastic modulus of the granite decreases with the heating temperature. Water cooling will have a stronger effect on the reduction of the elastic modulus than natural cooling. The maximum difference value (2.02 GPa) of the elastic modulus under the different cooling methods occurs at the temperature of 800°C. (4) Poisson’s ratio of the granite increases with heating temperature, and the cooling method does not have an evident effect on it. The relationship between Poisson’s ratio and the heating temperature under different cooling methods can be described using the linear model. (5) According to the influence of the temperature on the peak stress, the elastic modulus, and Poisson’s ratio, the heating temperature domain can be divided into the unapparent zone, the significant zone, and the mitigation zone. (6) The thermal stress due to the nonuniform temperature field and the different thermal expansion coefficients is incompatible. Such incompatibility stresses the essences of the degradation of the mechanical properties of the granite.

Hemostatic materials are increasingly important in civilian and military clinics. In this work, a hydrogel was fabricated from hydroxypropyl chitosan (HPCS) and soy protein isolate (SPI) through the crosslinking of epichlorohydrin. Effects of SPI content on the structure, and physical and biological properties of the prepared hydrogels were characterized using Fourier-transform infrared spectroscopy, X-ray diffractometry, scanning electron microscopy, water uptake testing, mechanical properties testing, MTT assay, hemolysis ratio testing, and routine blood coagulation test. The results indicated that the hydrogels showed high water uptake ability and compressive strength. The

The influence of Ni2+ concentration on biohydrogen production was investigated using waste activated sludge as substrate. The degradation of substrate, accumulation of volatile fatty acids (VFAs) and distribution of microbial community were analyzed to provide information for influencing mechanisms of Ni2+ addition. The experimental results demonstrated that the efficiency of hydrogen fermentation from waste activated sludge could be significantly improved. The optimal Ni2+ concentration was 5 mg/L, and under this concentration, the cumulative hydrogen production was 1.29 times of the control group. The degradation of soluble chemical oxygen demand (SCOD) increased from 25.21% to 27.69% when the added Ni2+ concentration was 5 mg/L. The analysis of microbial community distribution revealed that Ni2+ decreased the microbial diversity, and provided more suitable condition for the microbial growth and activity of hydrogen-producers. Citrobacter was the dominant hydrogen-producers in the control group, they changed into Enterococcus when 5 mg/L Ni2+ was added. Besides, the proportion of Clostridium_sensu_stricto_1, which is regarded as the primary hydrogen-producing bacteria under numerous operating conditions, was also significantly increased in the presence of Ni2+.

Based on reverse engineering, product innovation design and 3D-printing technology, a technical route for the rapid design and development of helmet products has been constructed, and optimize the product production process, reduce the product development cycle, improve production efficiency, and complete the personalized design of helmets to improve the comfort of personnel wearing. The point cloud data of the physical model were collected by the 3D scanner, and imported to the reverse processing software (Geomagic Studio) for data processing, surface reconstruction and surface fitting. In this way, the section curve of the repaired head surface was extracted. Then, the extracted information was sent to the forward design software (SolidWorks) through the parameter exchange command for the forward design of the helmet, and the 3D model was subsequently printed. Effectively solve the traditional design method for complex surface modelling design and manufacturing, forward software measurement deviation, modelling design process is complex and tedious, time-consuming and labor-intensive, cannot well meet the product design, processing and manufacturing process is relatively cumbersome, long production cycle and other design defects, speed up enterprise product development, shorten the cycle and reduce costs. Furthermore, the adoption of 3D printing technology to output the designed 3D digital model effectively shortens the product development cycle.

The development of efficient strategies to recycle lithium-ion battery (LIB) electrode materials is an important yet challenging goal for the sustainable management of battery waste. This work reports a facile and economically efficient method to convert spent cathode material, LiFePO4, into a high-performance NiFe oxy/hydroxide catalyst for the oxygen evolution reaction (OER). Herein, Ni-LiFePO4 is synthesized via the wetness impregnation method and further evolves into defect-rich NiFe oxy/hydroxide nanosheets during the OER. The introduction of the Ni promoter together with in situ evolution strengthens the electronic interactions among the metal sites and creates an abundance of defects. Experimentally, the evolved Ni-LiFePO4 delivers a low overpotential of 285 mV at 10 mA cm−2 and a small Tafel slope of 45 mV dec−1, outperforming pristine LiFePO4 and is even superior to the benchmark catalyst RuO2. Density functional theory (DFT) calculations reveal that the introduction of Ni effectively activates Fe sites by optimizing the free energy of the *OOH intermediate and that the abundance of oxygen defects facilitates the oxygen desorption step, synergistically enhancing the OER performance of LiFePO4. As a green and versatile method, this is a new opportunity for the scalable fabrication of excellent electrocatalysts based on spent cathode materials.

Based on visual cortical theory of Rybak, a new heterogeneous Rybak neural network (HRYNN) model is proposed for image enhancement. HRYNN is constructed with several Rybak neural network (RYNN) models proposed, which have different parameters corresponding to different neurons. We show that HRYNN can better represent prior information for edge detail enhancement than the logarithmic domain. To capture different resolution texture features of image, a novel receptive field model is proposed to solve the problem of detail enhancement. HRYNN model has excellent enhancement effect on the edge details of image based on the receptive field’s lateral inhibitory characteristics. Moreover, the experimental enhancement results of the colour images from Berkeley image Dataset show the validity and efficiency of the proposed enhancement method. Finally, three evaluation indicators are employed to measure the enhancement result.