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Highlights: Plasma-assisted phosphorization has been used to prepare defect-rich metal phosphides. The p-NiCoP/NCF@CC shows high activities and excellent stability for the hydrogen evolution reaction and the oxygen evolution reaction. The p-NiCoP/NCF@CC shows great potential for overall water splitting. This work reports the use of defect engineering and carbon supporting to achieve metal-doped phosphides with high activities and stabilities for the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) in alkaline media. Specifically, the nitrogen-doped carbon nanofiber-supported Ni-doped CoP3 with rich P defects (Pv·) on the carbon cloth (p-NiCoP/NCFs@CC) is synthesized through a plasma-assisted phosphorization method. The p-NiCoP/NCFs@CC is an efficient and stable catalyst for the HER and the OER. It only needs overpotentials of 107 and 306 mV to drive 100 mA cm−2 for the HER and the OER, respectively. Its catalytic activities are higher than those of other catalysts reported recently. The high activities of the p-NiCoP/NCFs@CC mainly arise from its peculiar structural features. The density functional theory calculation indicates that the Pv· richness, the Ni doping, and the carbon supporting can optimize the adsorption of the H atoms at the catalyst surface and promote the strong electronic couplings between the carbon nanofiber-supported p-NiCoP with the surface oxide layer formed during the OER process. This gives the p-NiCoP/NCFs@CC with the high activities for the HER and the OER. When used in alkaline water electrolyzers, the p-NiCoP/NCFs@CC shows the superior activity and excellent stability for overall water splitting. [ABSTRACT FROM AUTHOR]

Salix sand barriers have been widely used in arid and semi‐arid regions of northern China as an environmentally friendly approach to control wind erosion. However, the inherent variability in length and thickness of Salix branches complicates achieving the desired fence porosity, typically resulting in an error of approximately 10% or more. This defect affects the fence's wind protection, thereby limiting their broader application. To address these challenges, we conducted a field experiment in the Hobq Desert, where we established Salix fences with porosities of 23%, 37%, and 44%, and measured the airflow velocities around these fences. The results indicated that the fence with 37% porosity exhibited the most effective sheltering effect, providing a protection distance up to 7.14 times of the fence height. A total of 44% porosity fences are also reasonably effective for practical purposes. On the other end of the spectrum, fences with 23% porosity demonstrated a better sediment interception than its high porosity peers, achieving an interception rate of 81.46%. Therefore, we conclude that organic fences made from Salix branches can serve as efficient windbreaks. Our findings provide foundational data for the application of organic fences in arid and semi‐arid regions of northern China, and potentially similar environments globally. [ABSTRACT FROM AUTHOR]

Secondary aluminum ash is a kind of common solid waste which will pollute the environment without any treatment. In this study, the influence of secondary aluminum ash on the rheological properties and the initial setting time of fresh reactive powder concrete (RPC) are researched. Meanwhile, the mechanical properties and the drying shrinkage rates of RPC with the secondary aluminum ash are determined. The electrical parameters of RPC with the secondary aluminum ash are measured. Scanning electron microscopy is obtained to reflect the internal structure of RPC. Results show that the addition of secondary aluminum ash can lead to decreasing the fluidity and increase the yield shear stress of fresh RPC paste by varying rates of 16.1% and 58.3%, respectively. The addition of secondary aluminum ash can decrease the flexural and compressive strengths of RPC cured for 1 day by the decreasing rates of 0~18.7% and 0~19.3%. When the curing age is 28 days, the flexural and compressive strengths of RPC are increased by 0~9.1% and 0~19.1% with adding the secondary aluminum ash. The secondary aluminum ash can promote the condensation of RPC. The addition of the secondary aluminum ash can decrease the electrical resistance of RPC by an order of magnitude. The relationship between the electrical resistance and the electrical reactance fits the quadratic function equation. The electrical resistance of the pore solution increases in the form of a quadratic function with the mass ratio of the secondary aluminum ash. The dry shrinkage rates of RPC cured for 1 day and 28 days are decreased by 0~36.4% and 0~41.3% with the increasing dosages of secondary aluminum ash. As obtained from the microscopic testing results, the secondary aluminum ash can improve the compactness of hydration products. [ABSTRACT FROM AUTHOR]

In order to prepare cement concrete with high mechanical properties and durability, nano-stainless steel powder reactive powder cement concrete (RPC) was manufactured. The dosage of nano-stainless steel powder ranged from 0% to 1.2% by the total volume of the RPC. In this study, the compressive and flexural strengths of the RPC with nano-stainless steel powder were determined, the dry shrinkage rate of the RPC was tested and the electrical resistance and alternating current (AC) impedance spectrum of the RPC were measured; moreover, the corresponding strain-sensing properties were investigated, and the scanning electron microscope (SEM) was used for observing the microstructures of the RPC. The results showed that the RPC with 1.0% nano-stainless steel powder exhibited the threshold values of the mechanical strengths. The maximum flexural strength and compressive strength were 16.1% and 14.2% higher than the minimum values. The addition of the nano-stainless steel powders reduced the dry shrinkage rate by 12.1%–39.8%. The electrical resistance of the RPC decreased in the form of the cubic function with the volume fraction of the stainless steel powders. The 1.0% nano-stainless steel powder was the threshold value for the electrical resistance and piezoresistive performance. The relationship between the electrical reactance and electrical resistance fitted well with the quadratic function. As obtained from the SEM results, the addition of the nano-stainless steel powder could effectively improve the compactness of the hydration products. [ABSTRACT FROM AUTHOR]

Exploring non-noble oxygen electrode catalysts for efficient and stable oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is of great importance for high-performance rechargeable zinc–air batteries. In this work, we reported for the first time that 2-methylimidazole (2-MIM) can effectively regulate the loading of transition metals nickel (Ni) and iron (Fe) on nitrogen-doped graphene hollow spheres (NGHS) entangled with N-doped carbon nanotubes (NCNTs). The introduction of 2-MIM not only effectively controls the size of loaded metal nanoparticles (NPs), but also plays a significant role in the formation of the metal alloy. In addition, the introduction of Ni is the key factor for the self-growth of NCNTs, and the introduction of Fe serves a key role in promoting the formation of metal nitrides and improving the bifunctional performance of the electrode materials. The NiFe3@NGHS-NCNTs obtained after optimization of the preparation parameters exhibit excellent ORR/OER bifunctional electroactivity and long-term durability, which has obvious advantages over commercial 20% Pt/C + RuO2 catalysts. Density functional theory (DFT) calculation demonstrated that the NiFe3 alloy is strongly coupled with N-doped carbon (NC), endowing the C active site with moderate positive charge and valence state, thus improving the ORR and OER performance of the NiFe3@NGHS-NCNTs. More importantly, a rechargeable liquid electrolyte Zn–air battery (ZAB) with NiFe3@NGHS-NCNTs as the air cathode delivers a comparatively small charge–discharge voltage gap of 0.737 V at 10 mA cm−2 and displays maximum power density of 126.54 mW cm−2, which is higher than that of the commercial 20% Pt/C + RuO2 catalyst (102.63 mW cm−2). The fabricated flexible all-solid-state (ASS) rechargeable ZAB with NiFe3@NGHS-NCNTs exhibits a higher open-circuit voltage (OCV) (1.44 V) and peak power density (102.82 mW cm−2) than ASS-ZABs based on 20% Pt/C + RuO2 (1.42 V, 35.35 mW cm−2). [ABSTRACT FROM AUTHOR]

This work reports a novel approach for the synthesis of FeCo alloy nanoparticles (NPs) embedded in the N,P‐codoped carbon coated nitrogen‐doped carbon nanotubes (NPC/FeCo@NCNTs). Specifically, the synthesis of NCNT is achieved by the calcination of graphene oxide‐coated polystyrene spheres with Fe3+, Co2+ and melamine adsorbed, during which graphene oxide is transformed into carbon nanotubes and simultaneously nitrogen is doped into the graphitic structure. The NPC/FeCo@NCNT is demonstrated to be an efficient and durable bifunctional catalyst for oxygen evolution (OER) and oxygen reduction reaction (ORR). It only needs an overpotential of 339.5 mV to deliver 10 mA cm−2 for OER and an onset potential of 0.92 V to drive ORR. Its bifunctional catalytic activities outperform those of the composite catalyst Pt/C + RuO2 and most bifunctional catalysts reported. The experimental results and density functional theory calculations have demonstrated that the interplay between FeCo NPs and NCNT and the presence of N,P‐codoped carbon structure play important roles in increasing the catalytic activities of the NPC/FeCo@NCNT. More impressively, the NPC/FeCo@NCNT can be used as the air‐electrode catalyst, improving the performance of rechargeable liquid and flexible all‐solid‐state zinc–air batteries. [ABSTRACT FROM AUTHOR]

This work reports a novel approach for the synthesis of FeCo alloy nanoparticles (NPs) embedded in the N,P‐codoped carbon coated nitrogen‐doped carbon nanotubes (NPC/FeCo@NCNTs). Specifically, the synthesis of NCNT is achieved by the calcination of graphene oxide‐coated polystyrene spheres with Fe3+, Co2+ and melamine adsorbed, during which graphene oxide is transformed into carbon nanotubes and simultaneously nitrogen is doped into the graphitic structure. The NPC/FeCo@NCNT is demonstrated to be an efficient and durable bifunctional catalyst for oxygen evolution (OER) and oxygen reduction reaction (ORR). It only needs an overpotential of 339.5 mV to deliver 10 mA cm−2 for OER and an onset potential of 0.92 V to drive ORR. Its bifunctional catalytic activities outperform those of the composite catalyst Pt/C + RuO2 and most bifunctional catalysts reported. The experimental results and density functional theory calculations have demonstrated that the interplay between FeCo NPs and NCNT and the presence of N,P‐codoped carbon structure play important roles in increasing the catalytic activities of the NPC/FeCo@NCNT. More impressively, the NPC/FeCo@NCNT can be used as the air‐electrode catalyst, improving the performance of rechargeable liquid and flexible all‐solid‐state zinc–air batteries. [ABSTRACT FROM AUTHOR]

We propose and demonstrate a frequency modulated continuous-wave (FMCW) light detection and ranging (LiDAR) system, which employs double-sideband modulation combining with injection-locking to generate triangular linear frequency modulation light source. A fiber laser working as master laser is modulated by a Mach-Zehnder modulator to produce two first-order sidebands with tuning range of 8–14 GHz, one of which is extracted and amplified by a slave distributed feedback laser. A large carrier suppression ratio up to 20 dB is realized. The experiment results show the spatial resolution of the proposed LiDAR is 2.5 cm, equaling to the theoretical value. The velocity measurement is also performed by extracting Doppler shift. Finally, by combining the proposed LiDAR with 2-axis mechanical galvanometer scanner, the 3D imaging with high precision is realized, and the real scene is well restored. The proposed LiDAR system realizes pure linear frequency modulation without complex linearization algorithm or clock sampling circuit, and has advantages of simple structure and high precision. [ABSTRACT FROM AUTHOR]

The porous carbon-coated LiFePO4 (LFP) nanocrystals synthesized by in situ plasma-assisted pyrolysis are reported. The particle size of LFP nanoparticles is well controlled through the coating of polyaniline (PANI) on FePO4. The effect of PANI content in FePO4/PANI on the morphology and electrochemical performance of LiFePO4 particles is extensively investigated. Results show that the optimized amount of PANI in FePO4/PANI is 10.16% and the corresponding carbon content in activated porous carbon-coated LiFePO4 (LFP/AC-P4) is 9.27%. The primary particle size of LFP/AC-P4 is 20~50 nm which are wrapped and connected homogeneously and loosely by activated porous carbon. The LFP/AC-P4 composite delivers a capacity of 166.9 mAh g−1 at 0.2 C, which is much higher than carbon-encapsulated LiFePO4 nanocomposite (LFP/C) synthesized without the assistance of plasma pyrolysis (163.5 mAh g−1). Even at high rate of 5 C, a specific capacity of 128.4 mAh g−1 is achievable with no obvious capacity fading after 250 cycles. [ABSTRACT FROM AUTHOR]

Herein, we report the facile synthesis of three-dimensional porous nitrogen-doped carbon materials (PNCs) with extra high nitrogen content by means of directly carbonizing nitrogen-enriched precursors, 1,2,4-benzenetriamine dihydrochloride (BTD) and 1,2,4,5-tetraaminobenzene (TAB) with the aid of FeCl3·6H2O. The influence of the carbonization temperature and selection of precursors on the morphologies and properties of PNCs were studied using scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET), X-ray diffraction (XRD), etc. Their electrochemical performance was characterized using galavanostatic charge–discharge (GCD), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). A PNC obtained by carbonizing BTD at 450 °C exhibits a high nitrogen content (about 23.85 wt%), and large surface area (1335 m2 g−1). As a result, it shows a high specific capacitance of 482 F g−1 at a current density of 1 A g−1 in 1 M H2SO4 and excellent cycle stability, 98% retention after 12 000 cycles. Furthermore, a liquid sandwich-structured symmetric supercapacitor assembled from this PNC can power a light stopwatch for about 10 minutes, demonstrating that it is a promising material for supercapacitor electrodes. [ABSTRACT FROM AUTHOR]

The hydrothermal reaction of cobalt salt in the presence of 4-pyridyl-tetrathiafulvalene-4-pyridyl (4-py-TTF-4-py) and terephthalic acid (PTA) has been employed for the preparation of a novel metal-organic framework (MOF), i.e., (4-py-TTF-4-py)2M2(PTA)4 (M = Co2+). The obtained MOF is then used as a starting material for the synthesis of Co nanoparticles embedded in N,S-codoped carbon layer and supported on multi-walled carbon nanotubes (Co@NSC/MWCNTs) through the high-temperature calcination. Specifically, the calcination leads to the formation of N,S-codoped carbon-coated Co nanoparticles with simultaneous growth on the MWCNTs due to decomposition of the MOF. When used as the electrocatalyst, the Co@NSC/MWCNTs are found to have a higher activity for the oxygen reduction reaction (ORR) and follow a four-electron pathway. The catalytic activity of the Co@NSC/MWCNTs is much higher than that of the pure MWCNTs and the MOFs/MWCNTs. Although the Co@NSC/MWCNTs still exhibit slightly higher overpotential for the ORR, it is indeed more kinetically facile than the commercial Pt/C catalyst, as demonstrated by its higher limiting current density and lower Tafel slope. Additionally, the Co@NSC/MWCNTs also show superior stability and better tolerance to methanol crossover and CO poisoning, compared with those of the commercial Pt/C catalyst. These results strongly suggest that the Co@NSC/MWCNTs could be used as one of the most promising ORR electrocatalysts for the ORR with great potential to replace the Pt/C. The work present here opens up a new route for the design of carbon-integrated ORR electrocatalysts with high performance from a great number of available and yet rapidly growing MOFs. [ABSTRACT FROM AUTHOR]

Porcine reproductive and respiratory syndrome virus (PRRSV) is a pathogen that severely disrupts swine production. Despite sustained efforts, the disease is still endemic, with high mortality and morbidity. New antiviral strategies to control PRRSV are needed. Griffithsin, a red algal lectin, has potent antiviral effect on several human enveloped viruses, but this effect has not been demonstrated on PRRSV. Here, we first tested the in vitro antiviral activity of Griffithsin against PRRSV. Griffithsin exerted strong saccharide-dependent antiviral activity against PRRSV, probably through interactions with glycans on the surface of PRRSV that interfered with virus entry. Furthermore we revealed that Griffithsin’s action on PRRSV involved blocking viral adsorption, and it had no effect on viral penetration. Besides Our findings also suggested that Griffithsin may interfere with cell-to-cell spread to prevent virus transmission. The remarkable potency profile of Griffithsin supports its potential value as an antiviral agent against PRRSV. [ABSTRACT FROM AUTHOR]

The activity of Schwann cells (SWCs) is very important in trauma-induced nerve repair, and tumour necrosis factor-α (TNF-α) produced during tissue injury inhibits the viability of SWCs, which delays the repair of peripheral nerves. Loganin is an iridoid glycoside that has been shown to alleviate a variety of cytotoxic effects. In the current study, we evaluated the potential efficacy and the mechanism of action of loganin in TNF-α-induced cytotoxicity in SW10 cells. The experimental results indicated that loganin blocked TNF-α-mediated Smad2 activation, downregulated the expression of the G1 phase cell cycle inhibitor p15IN4KB, and upregulated the expression of the G1 phase cell cycle activator cyclin D1-CDK4/6, which upregulated E2F-1-dependent survivin expression and relieved TNF-α-induced apoptosis in SW10 cells. The protective effect of loganin on SWCs has potential medicinal value in the promotion of peripheral nerve repair and is significant for studies in the field of tissue regeneration. [ABSTRACT FROM AUTHOR]

Amine functionalized holey graphene (AFHG), synthesized by the hydrothermal reaction of GO and ammonia and the subsequent KOH etching, has been used as a metal-free catalyst for the oxygen reduction reaction (ORR). It shows that AFHG is highly active for the ORR and exhibits higher electrocatalytic activity than graphene, nitrogen-doped graphene (NG) and amine functionalized graphene (AFG), which could be demonstrated from its higher current density and more positive half-wave and onset potentials for the ORR. Although AFHG also exhibits a slightly higher overpotential towards ORR, it is indeed more kinetically facile than the commercial JM Pt/C 40 wt%. Its higher electrochemical performance could be attributed to the presence of the electron donating group (e.g. amine) and a large number of holes in its sheet plate and the porous structure in its randomly stacked solid, which provide AFHG with higher electrical conductivity, more active edge N atoms and easier accessibility to oxygen, respectively. The stability measurements show that AFHG is more stable than graphene, NG, AFG and the JM Pt/C 40 wt% and exhibits higher immunity towards methanol crossover and CO poisoning than the JM Pt/C 40 wt%. Over 10 h of the ORR, AFHG loses only <7% of its original activity in the absence of methanol or CO, and the introduction of methanol or CO has no effect on its oxygen reduction activity, which makes it highly desirable as a metal-free catalyst for the ORR. [ABSTRACT FROM AUTHOR]