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Sodium carbonate (SC) activated ground granulated blast-furnace slag (GGBS) and fly ash (FA) is a potential substitute of traditional cement with ultra-low carbon footprint. However, its hydration rate and strength growth are limited, owing to the slow leaching of ions during the activation of weak base. In this work, 60% wet-grinded GGBS and 40% FA were blended as the binder, and two organic alkalis, i.e. triethanolamine (TEA) and triisopropanolamine (TIPA), were adopted to facilitate the ions dissolution and pozzolanic reaction of SC activated GGBS-FA blended cementitious material (SCSF). The compressive strength was tested and the hydration kinetics was studied by hydration heat and chemical shrinkage. Besides, ions leaching behavior was characterized by ICP; hydrates and microstructure were also detected by XRD, TG-DTG and SEM. Results indicated that the addition of TEA or TIPA significantly promoted the ions dissolution. 0.05% TEA increased the concentration of leached Ca2+, Al3+ and Fe3+ by 36%, 33% and 1545%, respectively. This solubilizing effect was also found in TIPA. Moreover, these two chemicals could promote the formation of hydrates, such as C-S(A)-H gel, hydrotalcite, calcite and aragonite, especially at the early period; these also activated the hydration process of SCSF effectively, and the compressive strength of the mortar reached above 40.0 MPa at 7 d and 48.0 MPa at 28 d. The carbon emission of the designed system is 85.9% and 55.9% lower than that of PC and strong base activated GGBS system, respectively.

Poly(ethylene oxide) (PEO) is a classic matrix model for solid polymer electrolyte which can not only dissociate lithium-ions (Li+), but also can conduct Li+ through segmental motion in long-range. However, the crystal aggregation state of PEO restricts the conduction of Li+ especially at room temperature. In this work, an amorphous polymer electrolyte with ethylene oxide (EO) and propylene oxide (PO) block structure (B-PEG@DMC) synthesized by the transesterification is firstly obtained, showing an ionic conductivity value of 1.1 × 10−5 S/cm at room temperature (25 °C). According to the molecular dynamics (MD) simulation, the PO segments would lead to an inconsecutive and hampered conduction of Li+, which is not beneficial to the short range conduction of Li+. Thus the effect of transformation of aggregation state on the improvement of ionic conductivity is not enough, it is necessary to further consider the different coupled behaviours of EO and PO segments with Li+. In this way, we blend this amorphous polymer (B-PEG@DMC) with PEO to obtain a dual range ionic conductive solid polymer electrolyte (D-SPE) with further improved ionic conductivity promoted by constructing a dual range fast ionic conduction, which eventually shows a further improved ionic conductivity value of 2.3 × 10−5 S/cm at room temperature.

The aqueous Zinc-base batteries such as the Zn-air battery and the Zn-ion battery, featured with low-cost, high safety, high specific capacity and environmental-friendliness, have attracted intensive attention for energy storage. For high performance Zinc-base batteries, the electrocatalysts with good conductivity, convenient mass transfer path and adequate accessible active sites are demanded. Herein, we have fabricated transition-metal/nitrogen co-doped honeycomb-like carbon materials with hierarchical porous structure through a freeze-drying and one-step pyrolysis method. The as-prepared FeZnN-C are used as cathode materials of Zinc-air battery, the Zinc-air battery displays high peak power density of 257 mW cm-2, superior discharging voltage platform around 1.36 V and large specific capacity of 785 mAh gZn-1. Meanwhile, the prepared Zn/ZnN-C was used as anode of a Zinc-ion battery which exhibits great cycle stability and high charging/discharge rate. Our work provides a novel and facile method to construct highly efficient electrocatalysts with hierarchical macro-meso-micro-porous structure and multi-active sites for application in the aqueous Zinc-base batteries.

Lithium metal batteries are considered as high energy density battery systems with very promising prospects and have been widely studied. However, The uncontrollable plating/stripping behavior, infinite volume change and dendrites formation of lithium metal anode restrict the application. The uncontrolled nucleation of lithium caused by the nonuniform multi-physical field distributions, can lead to the undesirable lithium deposition. Herein, a graphene composite uniformly loaded with Ag nano-particles (Ag NPs) is prepared through a facile Gamma ray irradiation method and assembled into self-supported film with layered structure (Ag-rGO film). When such film is used as a lithium metal anode host, the uncontrolled deposition is converted into a highly nucleation-induced process. On one hand, the Ag NPs distributed between the interlayers of graphene can preferentially induce lithium nucleation and enable uniform deposition morphology of lithium between interlayers. On the other hand, the stable layered graphene structure can accommodate volume change, stabilize the interface between anode and electrolyte and inhibit dendrites formation. Therefore, the layered Ag-rGO film as anode host can reach a high Coulombic efficiency over 93.3% for 200 cycle (786 h) at a current density of 1 mA cm−2 for 2 mAh cm−2 in carbonate-based electrolyte. This work proposes a facile Gamma ray irradiation method to prepare metal/3D-skeleton structure as lithium anode host and demonstrates the potential to regulate the lithium metal deposition behaviors via manipulating the distribution of lithiophilic metal (e.g. Ag) in 3D frameworks. This may offer a practicable thinking for the subsequent design of the lithium metal anode.

In the domain of 3D food printing, previously developed 3D candy printers focused majorly on soft candy materials, such as chocolate, gum, and jelly. These techniques also presented limitations in terms of reproducibility and model diversity. Accordingly, this study aimed to address these problems via investigation of the behavior of sugar, a printing material, with respect to the extrusion process of 3D hard candy manufacture and analysis of the reproducibility. Moreover, the relationship among the nozzle movement speed, extrusion speed, and pattern spacing was analyzed to derive the optimal conditions for the extrusion process for reproducing a 3D virtual model. It was observed that the pattern spacing was optimized at 0.9 mm, considering a stable manufacturing process and manufacturing speed. The optimized parameter values of nozzle diameter, nozzle-substrate distance, pneumatic pressure, control temperature, printing speed, and standoff distance were computed through a correlation analysis conducted with pattern spacing. Under these conditions, moldings with a total height of 6 cm could be built. Moreover, a considerably high reproducibility of the 3D model was achieved on consideration of changes in the pattern thickness according to the nozzle movement speed and extrusion speed. Overall, this study contributes to literature and bridges a gap therein by presenting a process technology for guaranteeing the reproducibility of 3D models. It also demonstrates that the production of personalized custom shapes will be effective and feasible in the future.

Glutathione and 2-aminopyridine are used as carbon sources to prepare carbon dots (CDs) by a one-step hydrothermal reaction. The results show that the average particle diameter of CDs is 8.64 nm with uniform size distribution and the fluorescence quantum yield is 13.62%. We further demonstrate that novel CDs possess highly selective sensing of Fe3+ from 0.2 to 200 μM with a low detection limit (0.194 μM). Meanwhile, the fluorescence of CDs can be repeated many times by the addition of S2−. Moreover, the CDs are used for biological imaging of living cells with well cell penetrability and low toxicity. Furthermore, it is successfully applied for anti-counterfeiting and information encryption. More interestingly, it can be doped with hydrogel and filter paper to prepare solid-phase sensors exhibiting high sensitivity and fast response, demonstrating their tremendous potential for the simple, rapid, and low-cost monitoring of Fe3+ and S2−.

Vascularization and bone regeneration are two closely related processes during bone reconstruction. A three-dimensional (3D) scaffold with porous architecture provides a suitable microenvironment for vascular growth and bone formation. Here, we present a simple and general strategy to construct a nanofibrous poly(l-lactide)/poly(ε-caprolactone) (PLLA/PCL) scaffold with interconnected perfusable microchannel networks (IPMs) based on 3D printing technology by combining the phase separation and sacrificial template methods. The regular and customizable microchannel patterns within the scaffolds (spacings: 0.4 mm, 0.5 mm, and 0.6 mm; diameters: 0.8 mm, 1 mm, and 1.2 mm) were made to investigate the effect of microchannel structure on angiogenesis and osteogenesis. The results of subcutaneous embedding experiment showed that 0.5/0.8-IPMs (spacing/diameter = 0.5/0.8) and 0.5/1-IPMs (spacing/diameter = 0.5/1) scaffolds exhibited more vascular network formation as compared with other counterparts. After loading with vascular endothelial growth factor (VEGF), VEGF@IPMs-0.5/0.8 scaffold prompted better human umbilical vein endothelial cells (HUVECs) migration and neo-blood vessel formation, as determined by Transwell migration, scratch wound healing, and chorioallantoic membrane (CAM) assays. Furthermore, the microangiography and rat cranial bone defects experiments demonstrated that VEGF@IPMs-0.5/0.8 scaffold exhibited better performance in vascular network formation and new bone formation compared to VEGF@IPMs-0.5/1 scaffold. In summary, our results suggested that the microchannel structure within the scaffolds could be tailored by an adjustable caramel-based template strategy, and the combination of interconnected perfusion microchannel networks and angiogenic factors could significantly enhance vascularization and bone regeneration., Graphical abstract Schematic diagram of nanofibrous scaffolds with interconnected perfusable microchannel networks for engineering of vascularized bone tissue.Image 1, Highlights • 3D-printed sacrificial templates are used to construct the scaffold with interconnected perfusable microchannel networks. • The microchannel structure within scaffolds can be tailored by changing the template specifications. • The introduction of VEGF in the microchannel of scaffold promotes the vascular network formation. • Microchannel structure and angiogenic factor within scaffold significantly enhance vascularization and bone regeneration.

Van der Waals heterostructures composed of different two-dimensional films offer a unique platform for engineering and promoting photoelectric performances, which highly demands the understanding of photocarrier dynamics. Herein, large-scale vertically stacked heterostructures with MoS2 and ReSe2 monolayers are fabricated. Correspondingly, the carrier dynamics have been thoroughly investigated using different ultrafast spectroscopies, including Terahertz (THz) emission spectroscopy, time-resolved THz spectroscopy (TRTS), and near-infrared optical pump-probe spectroscopy (OPPS), providing complementary dynamic information for the out-of-plane charge separation and in-plane charge transport at different stages. The initial charge transfer (CT) within the first 170 fs, generating a transient directional current, is directly demonstrated by the THz emissions. Furthermore, the TRTS explicitly unveils an intermediate free-carrier relaxation pathway, featuring a pronounced augmentation of THz photoconductivity compared to the isolated ReSe2 layer, which likely contains the evolution from immigrant hot charged free carriers to bounded interlayer excitons (∼0.7 ps) and the surface defect trapping (∼13 ps). In addition, the OPPS reveals a distinct enhancement in the saturable absorption along with long-lived dynamics (∼365 ps), which originated from the CT and interlayer exciton recombination. Our work provides comprehensive insight into the photocarrier dynamics across the charge separation and will help with the development of optoelectronic devices based on ReSe2-MoS2 heterostructures.

Devising novel water-soluble carbon dots (CDs) with a facile and economical process is pivotal for the detection of ions in the environment. In this paper, novel nanoscale CDs (polyethyleneimine-2,...

In this work, nanofibrillated cellulose (NFC), LiFePO4 (LFP), and graphene (GR) were used as raw materials to prepare a flexible self-supporting electrode. NFC shows excellent mechanical properties and flexibility. NFC is used as the skeleton of the flexible electrode, coupling LFP and GR to form a conductive network structure. The Flexible electrodes show excellent flexibility and bendability. The mass of the flexible electrode no longer decreased significantly at temperature higher than 400 °C. The final residual rate of the flexible electrode is about 58%. The surface resistance of the flexible electrode is found to decrease by 93% with the content of LFP increasing from 25 to 45 wt%. The flexible electrode also shows higher electrochemical reaction activity and higher reversibility of Li+ extraction/intercalation with the increase of LFP and GR. At 0.1 C rate, the first discharge capacity is 121.47 mAh g−1, 146.76 mAh g−1 and 167.74 mAh g−1 for NFC/GR/LFP flexible electrode with 25 wt%, 35 wt%, and 45 wt% LFP, respectively. After 60 cycles of cycling, the capacity retention rate remains above 98%. Under 5 C rate, the first discharge capacity of these electrodes decrease to 29.87 mAh g−1, 77.41 mAh g−1, 99.84 mAh g−1, respectively, and after 770 cycles, the capacity retention rate is still above 90%. The AC impedance of the NFC/GR/LFP flexible electrodes with LFP content of 25 wt%, 35 wt%, and 45 wt% is 40 Ω, 15 Ω, and 9 Ω, respectively. The above results show that the flexible electrode exhibits excellent mechanical and electrochemical properties. The flexible electrode shows very high capacity retention rate no matter at low scan rate and or high scan rate. The cycle stability can be further enhanced by increasing the loading of active materials.

Gas discharge tube (GDT) breaks down discharge with surge overvoltage during long-term use. Notably, there is a risk of short-circuit failure due to the drop in insulation resistance after a certain number of discharges, which might be mainly caused by cumulative discharge. This article builds a cumulative discharge experiment platform to analyze the failure mechanism, performed the GDT whole life cycle cumulative discharge experiment and focused on the change law of its insulation resistance and breakdown voltage. For samples that are short-circuited, X-ray observation and vibration testing perpendicular to the GDT axis are conducted to examine the internal micro-morphology without damaging their external structure. The GDT is opened and its internal structure and material properties of the GDT cavity are compared and analyzed by scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) methods. The results indicated that the insulation resistance of GDT continuously decreased by several orders of magnitude in the last 10% of the life cycle, and the insulation resistance before failure is generally less than 1 $\text{k}\Omega $ . Through X-ray observation of the short-circuit failure sample, two different abnormal growth phenomena in the cavity are found, including flocs between the electrodes and deposits on the tube wall. Further analysis and experiments demonstrated that the flocs between the electrodes and the deposits on the tube wall are the primary factors causing the degradation of GDT insulation performance. The formation mechanism of the two short-circuit modes is explained by the difference in the splash angle and mode of metal particles of different sizes on the electrode surface.

The effect of Si content on the microstructures and growth kinetics of intermetallic compounds (IMCs) formed during the initial interfacial reaction (

Ni,Co-MOFs have been synthetized by a simple hydrothermal method. Subsequently, Co,Ni/N-doped porous carbon have been prepared by pyrolysis method using the Ni,Co-MOFs as precursor. The results show that the samples present high degree of graphitization. The Co-1–Ni-0.5/NC possesses the largest BET surface area (94.73 m2/g) and pore volume (0.456 cm3/g). The Co-1–Ni-0.5/NC presents the smallest HER overpotential (179 mV) and the best electrocatalytic activity for HER. The Co-0.5–Ni-0.5/NC and Co-1–Ni-0.5/NC have the relatively low overpotential for OER, which are about 348 mV and 383 mV, respectively. The smallest Tafel slope value indicates that Co-1–Ni-0.5/NC presents the best electrocatalytic reactive kinetics. Excellent electrocatalytic performance may be attributed to the more active sites, the higher specific surface area and mesopores as well as the lower charge-transfer resistance. The excellent HER and OER of Co-1–Ni-0.5/NC make its potential to be used on overall water splitting.

In recent years, transparent and flexible materials have been widely pursued in electronics and optoelectronics fields for usage as planar electrodes, energy conversion components and sensing units. As the most widely applied semiconductor material, the related progress in silicon is of great significance although with large difficulty. Herein, we report a one-step method to achieve flexible and transparent silicon nanowires aerogel membrane. A competitive carrier kinetics involving interfacial trapped carriers and the valence electrons transition is demonstrated, according to the photoelectric performance of a sandwiched graphene/silicon nanowires membrane/Al device, i.e., rapidly positive photoresponse dominated by laser excited free-carriers generation (∼ 500 ms) and subsequent slow negative photocurrent evolution due to laser heating involved multi-levels process (> 10 s). These results contribute to fabrication of silicon nanowire self-assembly structures and also the exploration of their optoelectrical properties in flexible and transparent devices.

Lattice anharmonicity is the essential ingredient for the description of the temperature-dependent dielectric response. Herein, using self-consistent phonon theory calculations that consider the lattice anharmonicity, we examined computational workflow to calculate dielectric permittivity. For this purpose, we selected the high symmetry cubic phase of SrTiO3, BaTiO3, PbTiO3, and KNbO3. It turns out that it is necessary to choose an appropriate set of a displacement–force dataset and the cutoff distance for quartic interatomic force constants. We were also able to predict Curie temperatures out of temperature-dependent dielectric constants of ferroelectric materials.

According to the profile processing, two forming processes are proposed, i.e., multi-point stamping forming and multi-point stretch forming. Through the finite element simulation, two forming processes are simulated and compared. The analysis results show that the longitudinal springback and transverse forming error of parts by multi-point stretch forming are smaller than those by multi-point stamping forming, so the multi-point stretch forming process is suitable for processing this kind of aluminum alloy profile.

The preparation of high-efficiency and low-cost electrocatalysts is vital to the development of green hydrogen energy. In this study, 3D NiCu electrodes with hierarchical micro-nano structure was constructed by a simple direct-write 3D printing technology and followed by the treatment of thermal oxidation - electroreduction steps. The composite structure of Cu NWs/Cu2O and Ni/NiO in the prepared 3D NiCu promotes the dissociation of water and the conversion of hydrogen, and the special micro-nano structure displays a large active surface area. Therefore, the 3D NiCu exhibits a low overpotential of 70 mV to deliver a current density of 10 mA cm−2. It demonstrates outstanding stability in the hydrogen evolution reaction experiment for 100 h in 1 M KOH. Overall, this research provides a pioneer of modified 3D printing to hydrogen production by water electrolysis.

The stellarator plasma device has been widely studied as one of the candidate solutions paralleling the ITER project, and its coupling with a fission blanket can bring benefits promoting the develo...

Multiply bonded lanthanide oxo groups are rare in coordination compounds and have not previously been reported for a surface termination of a lanthanide oxide. Here we report the observation of a Ce=O terminated ceria surface in a CeO2(111)‐(3 ×3 )R30° reconstruction of ≈3 nm thick ceria islands prepared on Pt(111). This is evidenced by scanning tunnelling microscopy (STM), low energy electron diffraction (LEED) and high‐resolution electron energy loss spectroscopy (HREELS) measurements in conjunction with density functional theory (DFT) calculations. A Ce=O stretching frequency of 775 cm−1 is observed in HREELS, compared with 766 cm−1 calculated by DFT. The calculations also predict that the Ce=O bond is weak, with an oxygen vacancy formation energy of 0.85 eV. This could play an important role in the facile removal of lattice oxygen from CeO2, accompanied by the reduction of CeIV to CeIII, which is a key attribute of ceria‐based systems in connection with their unique catalytic properties., A combined experimental and computational study of the (3 ×3 )R30° reconstruction of the CeO2(111) surface of an ultrathin ceria film is presented. The evidence collected indicates that the film is terminated by Ce=O groups.

Among active, semiactive, and passive vibration isolation methods, active control can provide the best isolation performances. However, high‐energy consumption hinders its wide application...

Novel spherical polymer nanoparticles were synthesized by hyperbranched polyethylenimine (hPEI) and 6-hydroxy-2-naphthaldehyde (HNA) via Schiff base reaction (one-pot reaction), which had great advantages in water solubility and green synthesis. Meanwhile, probe PEI-HNA could quickly detect Cu2+ in the range of 0–60 μM in 30 s with the detection limit of 243 nM. The fluorescence of PEI-HNA-Cu2+ could be recovered by the addition of S2− in 50 s with the detection limit of 227 nM. Based on the excellent optical properties, PEI-HNA has been used in the bioimaging of living cells with excellent cell penetrability and low toxicity. More importantly, PEI-HNA has been doped into filter paper, hydrogel, and nanofibrous film to prepare solid-phase sensors, displaying rapid response and excellent sensitivity. Moreover, the low-cost and simple preparation of these sensors offers great potential and possibilities for industrialization, which could help accelerate the development of sensors in environmental and biological fields.

Biomethanation is of great interest as it can transform CO2 to methane under ambient conditions. In particular, genetically engineered bacterium of Rhodopseudomonas palustris showed great promise for one-step biomethanation powered by solar energy, which is attractive for CO2 fixation as well as solar energy storage. However, biomethanation with R. palustris under visible light is inefficient due to its poor visible light response. In this study, CdS quantum dots with excellent visible light response were prepared and R. palustris/CdS hybrid cells were constructed. Interestingly, this bio-nano-hybrid cells showed high cell viability without significant cell damage, and the biomethanation performance of was enhanced about ~ 79% compared to that of the bare R. palustris cells. Moreover, the effects of different parameters on the methane production of this bio-nano-hybrid cells were determined, and the methane production rate was further improved by parameter optimization. This work demonstrated an efficient approach to reinforce the biomethanation of bacteria under unfavorable light wavelength, which would be helpful to extend the light spectra for photo-driven biomethanation.

Underwater pulsed arc discharge is a promising method for the inactivation of sewage microorganisms. Strong pressure wave plays an important role in the deactivation process. Researchers have conducted numerous studies on it, but there has not been a comprehensive study on its propagation in specific reactor. To achieve the industrial application of underwater pulsed arc discharge on sewage disinfection, this article has conducted a detailed study on the propagation of pressure wave in a cylindrical reactor based on experiments and numerical simulations. Several important conclusions are obtained through experiments. The pressure wave consists of three initial pulses generated by the cavity and their reflected waves. It spreads in the reactor at an average speed of 1655 m/s. The attenuation coefficient of the first initial pressure amplitude is 0.65 as the propagation distance increases. In addition, the maximum pressure amplitude decreases with increasing propagation distance, the attenuation coefficient of which is 0.93. The maximum pressure amplitude is always greater than 1.04 times the first maximum pressure amplitude. The following conclusion is obtained by simulation. When the propagation distance is 370 mm, the diameter of the reactor is reduced by 1/2, and the first maximum pressure amplitude will increase by 2.1 times. These results help further understand the distribution of pressure wave in the reactor and provide better guidance for the design of reactor.

Base on high theoretical capacity and synergistic effect of metal ions of transition metal vanadate composite, the MnV2O6/graphene (MnV2O6/rGO) nanocomposite was successfully synthesized through a hydrothermal method. The MnV2O6 nanoparticles were uniformly distributed and deposited on graphene networks. Benefited from the outstanding properties of the graphene nanosheets, the electrode conductivity was improved and the volume expansion was reduced. As an anode, the MnV2O6/graphene (MnV2O6/rGO) nanocomposite exhibited excellent lithium storage properties. An initial discharge capacity was 1350 mAh g-1, which increased to 1381 mAh g-1 after 100 cycles at 200 mA g-1, and showed a satisfactory reversible capacity of 640 mAh g-1 after 400 cycles at 5000 mA g-1.

Ceramic capacitors require promising energy storage properties to meet the demands of electronic industry which can be tailored by ferroelectric polarization and electrical breakdown strength. Electrical breakdown exhibits close relation to leakage current in advanced dielectric materials when stimulated by high levels of electric field. The suppression of leakage can be an effective strategy to elevate dielectric breakdown. In this work, Zr ions were employed to replace Ti ions in Ba0.3Sr0.7TiO3 ceramics to achieve the improvement of dielectric breakdown and then increase energy storage ability. Zr doping can obviously reduce the leakage current more than an order of magnitude by blocking the path between two adjacent Ti ions and increasing the distance of electron hopping. A promising energy storage density can be obtained with good fatigue endurance upto cycles of 105. This indicates that the strategy of suppressing leakage by trace amount of Zr doping is an effective approach to tailor energy storage behavior of dielectric ceramics.

In order to solve the hygroscopicity of ammonium polyphosphate (APP) and improve its flame retardancy, hydrophobic and flame retardant groups were introduced on the surface of APP by means of surface coating. It was blended with styrene acrylic emulsion (AAS) as the reinforcing resin and applied to the automobile engine air filter paper. The structure of the modified particles was confirmed by FT-IR TGA showed that the initial decomposition temperature of the modified particles decreased by 15 ℃, the decomposition rate decreased by about 5%, and the carbon residue rate at 800 ℃ increased from 21.73 to 44.92%; The DSC displayed that the blend resin had fine compatibility. Particle size analysis, scanning electron microscopy and transmission electron microscopy demonstrated that the large size modified APP particles were diffused into styrene acrylate emulsion particles and reconstituted to form a more compact and smaller particle size. The particles had a core shell structure with a shell thickness of 17 nm. These phenomena revealed the evolution of latex particles after blending. The air filter paper reinforced by blend resin has better mechanical properties and good water resistance. After absorbing water, the burst retention rate of air filter paper is more than 50%, and the stiffness retention rate is more than 20%. The combustion test and analysis by cone calorimeter analysis that the blend resin give the air filter paper excellent flame retardant performance.

A facile synthesis strategy for lignin-derived three-dimensional hierarchical porous carbon (LHPC) was developed in this work. The LHPC was synthesized by a one-step carbonization-activation process using lignin as a carbon precursor and wet KOH as an in situ chemical activation agent. Compared with dry KOH activation agent, the wet KOH shows exfoliation effect on assisting the formation of hierarchical porous structure of LHPC. The H2O plays a key role of an exfoliation agent in forming the hierarchical porous structure of LHPC. The as-prepared LHPC shows a high specific surface area of 2109 m2 g−1 and hierarchical pores. When used as an electrode material for supercapacitor, the LHPC exhibits excellent electrochemical performances, including a high capacitance of 254 F g−1 at 0.5 A g−1 and excellent rate capability with 59% capacitance retention at 20 A g−1. This study offers a convenient and practical approach to produce a high-rate hierarchical porous carbon material for supercapacitors.

The design and synthesis of low-cost and efficient bifunctional electrocatalysts for water splitting are critical and challenging. Hereby, a bimetallic phosphide embedded in a N and P co-doped porous carbon (FeCoP2@NPPC) material was synthesized by using sustainable biomass-derived N- and P-containing carbohydrates and non-noble metal salts as precursors. The obtained material exhibits good catalytic activities in hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and overall water splitting. The bimetallic alloy phosphide (FeCoP2) is the active site for electrocatalysis. Theoretical calculation indicates that the sub-layer Fe atoms and top-layer Co atoms in FeCoP2 exhibit a synergistic effect for enhanced electrocatalytic performance. The carbon matrix around the FeCoP2 can prevent the corrosion during the catalytic reactions. The hierarchically porous structure of the FeCoP2@NPPC material can promote the transfer of electrons and electrolyte, and increase the contact area of the active sites and electrolytes. N- and P-containing functionalities improve the wetting and conductivity properties of the porous carbon. Due to the synergistic effects, FeCoP2@NPPC requires a low overpotential of 114 and 150 mV at the current density of 10 mA cm-2 for HER in 0.5 M H2SO4 and 1.0 M KOH, and an overpotential of 236 mV for OER in 1.0 M KOH solution, which are much lower than those of FeP@NPPC and CoP@NPPC. Based on the density functional theory calculation, FeCoP2 yields the smallest Gibbs free energy change of rate-determining step among the samples, which leads to better electrochemical performances. In addition, when FeCoP2@NPPC was used as a bifunctional catalyst in water splitting, the electrolyzer needed a low voltage of 1.60 V to deliver the current density of 10 mA cm-2. Furthermore, this work provides a strategy for preparing sustainable, stable, and highly active electrocatalysts for water splitting.

The wet-laid hybrid nonwoven process can produce affordable carbon fiber-reinforced thermoplastic (CFRTP) because of its process simplicity, which can promote the application of CFRTP products in automobile weight reduction. The wet-laid hybrid nonwoven process involves two procedures, mainly: prepare preforms by a papermaking-like process and heat-molding compression. The parameters of heat-molding compression affect the quality of CFRTP directly, but there are not enough researches focusing on the effects of heat-molding compression parameters. This study aims to optimize the wet-laid hybrid nonwoven process to prepare recycled CFRTP. A proper carbon fiber content was determined firstly. Then, response surface methodology was used to optimize the heat-molding compression parameters. The effects of fiber length on composite properties were also investigated. The results showed that the fiber content of 30 wt% was the most suitable. The optimized heat-molding conditions were temperature, pressure, and time of 190°C, 2 MPa, and 10 min, respectively, leading to the lowest void content of 0.9%. CFRTP comprising carbon fibers with a length of 6 mm had the best properties, with the tensile strength of 59.34 MPa and flexural strength of 145.91 MPa.

The alkaline hydrogen evolution reaction (HER) is a half-reaction in the industrial water-alkali and chlor-alkali electrolytic technology. Nevertheless, most of the electrocatalysts exhibit inferior HER performance under alkaline conditions due to their sluggish kinetics involving high activation energy. Herein, we report a bimetallic Ni/MoN heterostructure nanorod electrocatalyst anchored on Ni foam (Ni–MoN@NF) via synchronous reduction and nitrogenization using dicyandiamide. The nitrided nanorod arrays have abundant active sites and good electron transfer ability, making their HER activity much higher than that of the corresponding Ni foam. The prepared Ni–MoN@NF electrocatalyst featured excellent hydrogen evolution performances with low overpotentials of 37.36 mV at 10 mA cm−2 and 110.83 mV at 100 mA cm−2, respectively, in alkaline media. Simultaneously, the resulting materials exhibited a significantly enhanced long-term durability over 100 h almost without any degradation. Particularly, the Ni–MoN@NF heterostructure nanorod still maintains excellent activity at high current density (the overpotential is only 283.83 mV at 1000 mA cm−2). This work will provide a positive strategy for the preparation and application of metal nitride-based electrocatalysts in the field of renewable energy.

The ability of storing electrostatic energy for a capacitor is largely dependent on the energy storage performances of the material used in the electronic components. In this case, a composition-driven Bi0.5Na0.5TiO3-based system, (1−x)(0.84Bi0.5Na0.5TiO3−0.16Bi0.5K0.5TiO3)−xBi(Mg0.5Ti0.5)O3 (NTB-KBT-100xBMT, x = 0.04–0.14) was designed and the enhanced energy storage density and efficiency with good thermal insensitivity were confirmed. The introduction of BMT can induce the relaxor characteristic due to the deconstruction of the ferroelectric long-range order, leading to the increase in dielectric breakdown and the improved energy storage performances. Particularly, the NTB-KBT-8BMT ceramic exhibits a high stored energy density (Wtotal = 2.88 J/cm3) and recoverable energy density (Wrec = 2.42 J/cm3) with good energy efficiency (η = 84.0%) under 320 kV/cm, indicative of potential application for energy storage components. Moreover, the NTB-KBT-8BMT ceramic exhibits typical temperature-independent character in a wide temperature range from 30 to 140 °C due to broad diffused phase transition. It can be concluded that constructing relaxor ferroelectrics is an effective approach to design novel dielectrics for pulse power applications.

Solar-driven water evaporation is an effective approach for using solar energy to purify seawater and wastewater. However, the high energy requirements of bulk water evaporation fundamentally restrict the practicality of solar freshwater production. Herein, we demonstrate an efficient hierarchical solar evaporator by combining polydopamine (PDA) and Ti3C2Tx MXene (MX) with a cellulose network skeleton of delignified wood (DW). By integrating activated water in a hydrated cellulose network and the synergistic photothermal effect between PDA and MX, the obtained PDMX@DW evaporator achieved a high evaporation rate of 2.08 kg m−2 h−1 and energy efficiency of 93.6% under 1 sun illumination. Differential scanning calorimetry and dark evaporation experiments indicated that the water in PDMX@DW exhibited a lower vaporization enthalpy (1915 J g−1) than bulk water (2440 J g−1). Raman spectral analysis and density functional theory calculations were used to investigate the structure of water molecules in the cellulose network, and it turns out that high contents of weakly hydrogen-bonded intermediate water were the most likely origin of the reduced vaporization enthalpy. More importantly, due to the interactive cellulose network structure and increased water supply rate, PDMX@DW exhibited excellent salt resistance and long-term stability in high-concentration brine. This work provides an effective method for breaking the evaporation limitation of the traditional wood-based evaporator and improving its salt resistance.

Oxide semiconductors have emerged as ideal candidate materials for flexible electronics and circuits. However, complementary flip-flops, which are the essential building blocks in sequential circuits, based on all-oxide thin-film transistors (TFTs) have not yet been demonstrated. Here, we employed n-type indium gallium zinc oxide and p-type tin monoxide to achieve J-K flip-flop (JK-FF) and D-type edge-triggered FF (D-FF). The operation properties of the JK-FF and D-FF were characterised both statically and dynamically. The output signals of the D-FF show great robustness. The D-FF shows very short propagation delay times of 17 and $40~\mu \text{s}$ from “0” to “1” and from “1” to “0”, respectively. Based on the D-FFs, a two-bit counter with 90 transistors was designed and fabricated successfully, acting as either up-counter or down-counter. To the best of our knowledge, this counter has the highest integration among the reported thin-film complementary sequential circuits based on all-oxide transistors to date.

The severe problem of water scarcity has led to the derivation and rapid development of solar vapor generation (SVG) technology. However, high cost, short-term stability in harsh environments, and potential secondary pollution restrict the practical application of most solar evaporators, especially in economically underdeveloped areas. Herein, we design a low-cost and long-term stable sponge evaporator by combining carbonized pomelo peel particles (CPPs) with chitosan (CS) and bamboo fibers (BFs) for efficient solar vapor generation. Due to the interactive macroporous architecture formed by BF's random interspersion in chitosan lamellae and the excellent CPP solar absorbers, the obtained robust CS/BFs/CPPs sponge evaporator exhibits a water evaporation rate of 2.317 kg m−2 h−1 with an energy conversion efficiency of 89.23% under one sun illumination. In addition, this sponge evaporator can work in harsh water environments such as acid–base solutions, dye solutions, and high salinity brine for long periods of time because of the stable interactive structure. More importantly, since all green materials for constructing the evaporator belong to the natural world, we demonstrate, the first example of ageing evaporator that can be reutilized and transformed into the soil. This work not only highlights the potential for developing low-cost and long-term durable solar evaporators but also contributes to the research direction for recycling and reutilization of ageing evaporators.

Iron phosphate-modified pollen microspheres (pollen@FePO4) were prepared and applied as sorbents for the removal of heavy metals (Cd2+ and Pb2+) from the aqueous solution. Batch sorption studies were conducted to investigate the effects of solution pH, contact time, sorbent dosage, and metal concentration on the adsorption process. The sorption of Cd2+ and Pb2+ ions on pollen@FePO4 corresponds to the pseudo-second-order model and Langmuir isotherm, which is similar to the unmodified pollen. At pH 5.92, pollen@FePO4 offers maximum adsorption capacities of 4.623 and 61.35 mg·g−1 for Cd2+ and Pb2+, respectively. The faster sorption kinetics and higher adsorption capacities of Cd2+ and Pb2+ ions onto pollen@FePO4 than pollen indicates that it might be a promising material for the removal of heavy metal ions in aqueous solutions. The possible adsorption mechanism involves electrostatic and chemisorption for Cd2+ and mainly complexion for Pb2+.

Exploring high-performance ceramics has been a great challenge for advanced electronic devices due to their limited capacitive energy storage densities in high-voltage pulse applications. The refinement of the microstructures can considerably optimize energy storage performances of dielectric ceramics by tailoring dielectric breakdown. Here, two-step sintering was employed to refine the microstructures of the lead-free 2.0 mol% Mn-doped 0.55 (0.94Na0.5Bi0.5TiO3-0.06BaTiO3)-0.45SrTiO3 bulk ceramics to offer the possibility of increasing energy storage performances. Compared with conventional sintering, fine grains by two-step sintering can be obtained, resulting in the obviously enhanced dielectric breakdown due to the increased fraction of grain boundary and the suppressed movement of domain walls. An ultrahigh charge energy storage density of 2.98 J/cm3 with a moderate efficiency (η) of 73.1% can be achieved at 28 kV/mm, accompanying with excellent temperature insensitivity in a wide range from 30 to 180 °C compared with the previous Na0.5Bi0.5TiO3-based derivatives. This work presented here strongly indicates that two-step sintering is a promising way to optimize the microstructural morphology and electrical performances of dielectric ceramics.

Rational design of micro-nano morphology and suitable crystalline structure are highly desired for metal hydroxides to achieve overall high-performance in the advanced electrodes for flexible supercapacitors. Herein, a novel wisteria flower-like microstructure of cobalt-nickel double hydroxide (CoNi-DH) is successfully constructed on carbon cloth (CC) using an in-situ hydrolysis-induced exchange process between hydroxide ions and organic ligands of the Co-MOF in four different kinds of solutions containing Ni2+. The as-prepared wisteria flower-like microstructure grown on CC shows vertically aligned arrays with high specific area and abundant active sites, which not only guarantee the CoNi-DH active materials to be thoroughly exposed in the electrolyte, resulting in highly effective pseudocapacitive energy storage, but also are beneficial to rapid and reversible redox kinetics and thus give rise to high-rate capability. In addition, compared to Ni(NO3)2, NiCl2, and Ni(CH3COO)2 solutions, the Ni2SO4 solution is found to facilitate the formation of the most regular morphology and the largest interlayer spacing on (003) plane of the layered nickel hydroxide phase in the resultant CoNi-DH. As a result, the optimal CoNi-DH-S@CC (CoNi-DH prepared in Ni2SO4) serves as an advanced electrode to show high-rate capability (only 13% Cs decay after a 15-fold current elevation) and a superior specific capacity (Cs) of 929.4 C g-1, which remarkably exceeds those of CoNi-DH-N (823.1 C g-1, in Ni(NO3)2), CoNi-DH-Cl (798.4 C g-1, in NiCl2), CoNi-DH-C (803.8 C g-1, in Ni(CH3COO)2), and other similar metal hydroxides. Moreover, with this CoNi-DH-S electrode as the positive electrode, the as-prepared asymmetric supercapacitor (ASC) delivers an impressive capacity of 204.8 C g-1, a superior energy density of 42.5 Wh kg-1, and satisfactory cycle life (81.5% reservation after 7500 cycles). As a proof-of-concept application, a quasi-solid-state ASC is further successfully fabricated based on the CoNi-DH-S electrode to exhibit encouraging application potential.

An electrochemical multicomponent reaction was established under catalyst-, chemical-oxidant-free and mild conditions, which provides an eco-friendly and simple protocol for constructing 4-selanylpyrazoles. A broad range of 4-selanylpyrazole derivatives could be obtained from easily available raw materials in good to excellent yields.

Pipes are widely applied across many industries such as the automotive, aerospace and air conditioning industries. With the development of industrial technology, various pipe materials and various pipe shapes are produced according to the purpose. Many researchers have been studied pipe bending technology to meet these diverse needs, and among them, the long-type elbow is a typical one that changes the moving direction of fluid or gas among various pipe types. Many researchers work on the pipe segment. In-process push-bending used in pipe bending is a bending process where a cut pipe is inserted into a die. Push-bending is effective for reducing the weight of parts that do not induce material loss, but the process is more complicated than the draw-bending process. In this study, we proposed an analytical model for a push-bending process in which a joint type mandrel was added to a long-type elbow made of C1220 material for weight reduction. The forming analysis is to verify the experiment by comparing the analysis result and the experimental result through the forming analysis software DEFORM to confirm the change of the wrinkle and the thickness of the bent pipe. In addition, we confirmed the wrinkling of the bent pipe and the die non-contact phenomenon depending on the angle and position of the joint mandrel and presented the optimum angle and center of gravity position of the joint mandrel using the experimental design method.

This paper provides a new treatment for gastric cancer with a new OMT delivery system. We synthesized MPEG-PCL, an amphiphilic polymer, to construct a nanoparticle encapsulated OMT by pH gradient method, and then examined the nanodrug’s therapeutic efficacy. An integral analytical method was used to characterize the structure of MPEG-PCL. The single factor method and orthogonal test were utilized to investigate the optimum preparation process. The morphology and average size of the OMT-NPs were analyzed by transmission electron microscopy and Zetasizer. CCK-8 assay and confocal fluorescent microscope were used to study the inhibitory effect on SGC-7901 gastric cancer cells. The average size of nanoparticles was 95.86±1.54 nm. The maximum encapsulation efficiency of OMT was 46.84±4.37%, while the drug loading content was 8.89±1.09%. The cumulative release of nanoparticles was 73.07±1.5%, inspected through dynamic dialysis in vitro. Compared with free OMT, OMT-NPs showed enhanced cytotoxic effects in SGC-7901 cells. The nanoparticles could efficiently deliver the OMT into the cancer cells and release it. The OMT delivery system prepared in this paper provides a potential platform for the treatment of gastric cancer.

To enhance the interface bonding of polyimide (PI)/carbon fiber (CF) composites, CFs were functionalized by introducing a polydopamine (PDA) transition layer, whose active groups provide absorption sites for the growth of molybdenum disulfide (MoS2) nanosheets and improve the bonding strength with PI. Uniform and dense MoS2 nanosheets with thicknesses of 30–40 nm on the surface of the PDA@CF were obtained via a subsequent hydrothermal method. As a result, the interface between the CF and the PI matrix becomes more compact with the help of the PDA transition layer and MoS2 nanosheets. This is beneficial in forming PI/CF-MoS2 composites with better thermal stability, higher tensile strength, and enhanced tribological properties. The lubricating and reinforcing effects of the hybrid CF-MoS2 in the PI composite are discussed in detail. The tensile strength of the PI/CF-MoS2 composite increases by 43%, and the friction coefficient and the wear rate reduce by 57% and 77%, respectively, compared to those of the pure PI. These values are higher than those of the PI/CF composites without MoS2 nanosheets. These results indicate that the CF-MoS2 hybrid material can be used as an additive to improve the mechanical and tribological properties of polymers.

Rational design and synthesis of hollow core–shell hetero-structures with high complexity still remains challenging for high gas-sensing performances. Here, ZIF-8@ZnO (zeolite imidazolate framework-8) core–shell material was synthesized using an easy-to-use hydrothermal reaction. ZnO is a kind of homologous metal oxide of ZIF-8 material. Therefore, without adding other zinc salts, the formation of ZIF-8@ZnO was completed in a one-pot reaction. Then a series of morphology and structure analysis including XRD, BET, SEM, EDX, etc. were carried out to study the positive effect of ZIF-8 film on the sensing performance of ZnO nanospheres. The results show that the ZIF-8 film uniformly covers the surface of porous ZnO nanospheres with a diameter of about 400 nm, forming a core–shell structure. Compared to the other volatile organic compounds (VOCs), ZIF-8@ZnO shows a higher sensitivity and selectivity to 50 ppm ethanol gas at an operating temperature of 220 °C, which can achieve 13.8. This is almost 2.7 times that of pure ZnO nanospheres (5.1). The obtained results show that ZIF-8@ZnO core–shell material not only greatly improves the sensitivity of the sensor, but also enhance the selectivity of ethanol gas sensing.

Hydrogen-peroxide-based low-temperature sterilization is a new sterilization technology for temperature-dependent medical devices. The effect of the process parameters of hydrogen-peroxide-based sterilizer on the sterilization performance of process challenge devices (PCDs) needs to be investigated. Sterilant amount, operating temperature, vacuum pressure, diffusion time, and chamber loading of the sterilizer on the sterilization performance of PCDs were adjusted. Seven PCDs with various morphologies and material containing biological indicators (BI) (EZTest, Geobacillus stearothermophilus) were used to evaluate the sterilization performance. The sterilization success rates of PCDs were 86, 71, and 57% with controlled temperature and pressure, diffusion time, and sterilant volume injection, respectively. The PCD material and structure also obviously affected sterilization performance. The sterilization of PCD A is the least successful for all parameters. Meanwhile, the sterilization of PCD B was influenced by the diffusion time and the sterilant injection volume. PCD B and PCD C were successfully sterilized by controlling the temperature and pressure. The weights and volume of the sterilization loading chamber resulted in a different sterilization performance. Sterilization performances of PCD 1, PCD 2, and PCD 3 were

In the microscopic observation of deforming metals, it is well known that crystallite defects that accommodate strain can occasionally become visible, namely, they introduce image contrast to their locality. For microscopic digital image correlation (DIC) applications, this is typically known as a disturbance. Here, we explore a potential upside of these image-intensity offsets, to present a new mode of differential imaging that exclusively displays the underlying plasticity agents. For this, the intensity-offset signal is isolated with residual intensity, essentially the differential between reference- and deformed-configuration intensity of each material point. The premise is showcased over an autocatalytic twin band in Magnesium AZ31, with an advanced DIC instrument that utilizes bright-field optical microscopy. With robust area-scanning that utilizes in-situ corrective measures, a material field of around 5000 grains (13 μm average size) is sampled with a maximal intragranular resolution (~250 data points per grain) for this technique. For added robustness against the intensity alterations, a DIC algorithm (Augmented Lagrangian DIC) that enforces global kinematic compatibility constraints is utilized. The calculated residual intensity map yields a detailed image of the twin networks that show a strong positional alignment with the strain localizations. At the band boundary, the twins (and their accompanying strain localization) protrude into the dormant material in a comb-like pattern. With a combination of high-resolution optics and defects that alter the surface topography, residual intensity presents a new in-situ microscopy mode that is tied to the DIC analysis. This principle also offers potential micro-deformation imaging capabilities for various other material-microscopy combinations.

Single-pass keyhole TIG welding (K-TIG) was used to weld 10-mm-thick Invar36 alloy plates without filler metal and groove preparation. The effects of joint gap, welding current, welding speed and a...

The flexural behavior of concrete-encased CFST box members is presented in this paper. Twelve bending tests were conducted to evaluate the influence of section size, steel tube diameter and bending direction on the performance of the concrete-encased CFST box beams. The test results were also discussed, including the observed failure patterns and developments of concrete cracks during the whole loading procedure. A numerical model was then developed to investigate the flexural behavior of the composite beams. The study of the full-range analysis, load transfer mechanism and stress distribution was carried out. Then the parametric studies were performed based on the FEA modeling. Finally, a simplified method for predicting the stiffness and flexural strength of the concrete-encased CFST box beams was presented.