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Soil salinization is a major abiotic factor threatening rapeseed yields and quality worldwide, yet the adaptive mechanisms underlying salt resistance in rapeseed are not clear. Therefore, this study aimed to explore the differences in growth potential, sodium (Na+) retention in different plant tissues, and transport patterns between salt‐tolerant (HY9) and salt‐sensitive (XY15) rapeseed genotypes, which cultivated in Hoagland's nutrient solution in either the with or without of 150 mM NaCl stress. The results showed that the inhibition of growth‐related parameters of the XY15 genotype was higher than those of the HY9 in response to salt stress. The XY15 had lower photosynthesis, chloroplast disintegration, and pigment content but higher oxidative damage than the HY9. Under NaCl treatment, the proline content in the root of HY9 variety increased by 8.47‐fold, surpassing XY15 (5.41‐fold). Under salt stress, the HY9 maintained lower Na+ content, while higher K+ content and exhibited a relatively abundant K+/Na+ ratio in root and leaf. HY9 also had lower Na+ absorption, Na+ concentration in xylem sap, and Na+ transfer factor than XY15. Moreover, more Na+ contents were accumulated in the root cell wall of HY9 with higher pectin content and pectin methylesterase (PME) activity than XY15. Collectively, our results showed that salt‐tolerant varieties absorbed lower Na+ and retained more Na+ in the root cell wall (carboxyl group in pectin) to avoid leaf salt toxicity and induced higher proline accumulation as a defense and antioxidant system, resulting in higher resistance to salt stress, which provides the theoretical basis for screening salt resistant cultivars. [ABSTRACT FROM AUTHOR]

Salinity is considered one of the abiotic stresses that have the greatest impact on soybean production worldwide. Lanthanum (La) is a rare earth element that can reduce adverse conditions on plant growth and productivity. However, the regulatory mechanism of La‐mediated plant response to salt stress has been poorly studied, particularly in soybeans. Therefore, our study investigated the mechanisms of La‐mediated salt stress alleviation from the perspectives of the antioxidant system, subcellular structure, and metabolomics responses. The results indicated that salt stress altered plant morphology and biomass, resulting in an increase in peroxidation, inhibition of photosynthesis, and damage to leaf structure. Exogenous La application effectively promoted the activity of superoxide dismutase (SOD) and peroxidase (POD), as well as the soluble protein content, while decreasing the Na+ content and Na+/K+ ratio in roots and leaves, and reducing oxidative damage. Moreover, transmission electron microscopy (TEM) demonstrated that La prevented the disintegration of chloroplasts. Fourier‐transform infrared spectroscopy (FTIR) analysis further confirmed that La addition mitigated the decline in protein, carbohydrates, and pectin levels in the leaves. Lanthanum decreased the leaf flavonoid content and synthesis by inhibiting the content of key substances in the phenylalanine metabolism pathway during NaCl exposure. Collectively, our research indicates that La reduces cell damage by regulating the antioxidant system and secondary metabolite synthesis, which are important mechanisms for the adaptive response of soybean leaves, thereby improving the salt tolerance of soybeans. [ABSTRACT FROM AUTHOR]

Static repellency and pressure resistance to liquids are essential for high‐performance super‐omniphobic surfaces. However, these two merits appear mutually exclusive in conventional designs because of their conflicting structural demands: Static liquid repellency necessitates minimal solid–liquid contact, which in turn inevitably undercuts the surface's ability to resist liquid invasion exerted by the elevated pressure. Here, inspired by the Springtail, these two merits can be simultaneously realized by structuring surfaces at two size scales, with a micrometric reentrant structure providing static liquid repellency and a nanometric reentrant structure providing pressure resistance, which dexterously avoids the dilemma of their structural conflicts. The nanometric reentrants are densely packed on the micrometric ones, serving as "armor" that prevents liquids invasion by generating multilevel energy barriers, thus naming the surface as the armored reentrants (AR) surface. The AR surface could repel liquids with very low surface tensions, such as silicone oil (21 mN m−1), and simultaneously resist great pressure from the liquids, exemplified by enduring the impact of low‐surface‐tension liquids under a high weber number (>400), the highest‐pressure resistance ever reported. With its scalable fabrication and enhanced performance, our design could extend the application scope of liquid‐repellent surfaces toward ultimate industrial settings. [ABSTRACT FROM AUTHOR]

With the development of social industry and the increase in domestic sewage discharge, pathogenic bacterial contamination in water has become a serious health and environmental problem. It is important to design sewage treatment reagents with effective pathogenic bacterial removal and recyclability. In this work, we developed a nanocomposite, Fe3O4@TiO2@MoS2, with once-for-all effects of photocatalytic, magnetic, and peroxidase-like activities for solving the above-mentioned problems. The loading of MoS2 may cause the band gap of Fe3O4@TiO2 to decrease from 3.11 eV to 2.85 eV, demonstrating increased photocatalytic activity under visible light, based on the synergistic impact of Fe3O4@TiO2 and MoS2. In return, the peroxidase-like activity of Fe3O4@TiO2@MoS2 was significantly higher than that of Fe3O4 and MoS2 alone, resulting in the generation of more hydroxyl radicals (˙OH) for combating the drug-resistant broad-spectrum β-lactamase-producing Escherichia coli and methicillin-resistant Staphylococcus aureus. The antibacterial mechanism study showed that Fe3O4@TiO2@MoS2 could effectively inhibit bacterial growth by destroying the bacterial biofilm and genome via the peroxidase-like activity as well as photocatalytic activity. In addition, Fe3O4@TiO2@MoS2 has excellent paramagnetic properties, which can achieve magnetic recovery after wastewater treatment. Even after three times of recycling, its antibacterial effect can remain above 98.8%. [ABSTRACT FROM AUTHOR]

The treatment of acid wastewater to remove organic matter in acid wastewater and recycle valuable resources has great significance. However, the classical advanced oxidation process (AOPs), such as the Fenton reaction, encountered a bottleneck under the conditions of strong acid. Herein, making use of the oxidation properties of CeAY (CeO2@acid clay), we built an AOPs reaction system without H2O2 under a strong acid condition that can realize the transformation of organic matter in industrial wastewater. The X-ray photoelectron spectroscopy (XPS) proved that the CeAY based on Ce3+ as an active center has abundant oxygen vacancies, which can catalyze O2 to produce reactive oxygen species (ROS). Based on the electron spin-resonance spectroscopy spectrum and radical trapping experiments, the production of •O2– and •OH can be determined, which are the essential factors of the degradation of organic compounds. In the system of pH = 1.0, when 1 mg CeAY is added to 10 mL of wastewater, the degradation efficiency of an aniline solution with a 5 mg/L effluent concentration is 100%, and that of a benzoic acid solution with a 100 mg/L effluent concentration is 50% after 10 min of reaction. This work may provide novel insights into the removal of organic pollutants in a strong acid water matrix. [ABSTRACT FROM AUTHOR]

Compacted graphite iron (CGI) has become the most ideal material for automotive engine manufacturing owing to its excellent mechanical properties. However, tools are severely worn during processing, considerably shortening their lifespan. In this study, we prepared a series of cemented carbide-coated tools and evaluated their coating properties in cutting tests. Among all tested coatings, PVD coating made of AlCrN (AC) presented with the best surface integrity and mechanical properties, achieving the best comprehensive performance in the coating test. The AC-coated tool also exhibited the best cutting performance at a low speed of 120 m/min, corresponding to a 60% longer cutting life and the lowest workpiece surface roughness relative to other coated tools. In the cutting test at a high speed of 350 m/min, the CVD double-layer coated tool (MT) with a TiCN inner layer of and an Al2O3 outer layer had a 70% longer cutting life and the lowest workpiece surface roughness relative to other coated tools. [ABSTRACT FROM AUTHOR]

Electrochemical conversion of N2 provides an eco-friendly approach for sustainable ammonia (NH3) production, but most electrocatalysts still suffer from low selectivity. Herein, a new three dimensional (3D) graphene aerogel-supported MoO2 and FeS2 nanocomposite (MoO2/FeS2/GA) was developed through mimicking the elemental composition and proportion of MoFe nitrogenase. Herein, MoO2 and FeS2 can both act as active sites for nitrogen fixation, while FeS2 plays the role of suppressing the competitive hydrogen evolution activity simultaneously. Moreover, the graphene aerogels can promote the charge transfer and increase the specific surface area of the nanocomposites. Based on the synergistic effects of such a ternary architecture, the electrocatalyst exhibits a high NH3 yield of 40.18 μg h−1 mgcat.−1 and outstanding faradaic efficiency of 37.44% at −0.25 V versus the reversible hydrogen electrode (RHE) in 0.1 M HCl. The selectivity of the as-proposed nanocomposite is superior to those of GA, FeS2/GA, MoO2/GA and most previously reported NRR electrocatalysts. Such a bioinspired strategy provides a new avenue to develop more high-efficiency catalysts with controllable activity for the NRR under ambient conditions. [ABSTRACT FROM AUTHOR]

To enable an efficient and cost‐effective electrocatalytic N2 reduction reaction (NRR) the development of an electrocatalyst with a high NH3 yield and good selectivity is required. In this work, Ti3C2Tx MXene‐derived quantum dots (Ti3C2Tx QDs) with abundant active sites enable the development of efficient NRR electrocatalysts. Given surface functional groups play a key role on the electrocatalytic performance, density functional theory calculations are first conducted, clarifying that hydroxyl groups on Ti3C2Tx offer excellent NRR activity. Accordingly, hydroxyl‐rich Ti3C2Tx QDs (Ti3C2OH QDs) are synthesized as NRR catalysts by alkalization and intercalation. This material offers an NH3 yield and Faradaic efficiency of 62.94 µg h−1 mg−1cat. and 13.30% at −0.50 V, respectively, remarkably higher than reported MXene catalysts. This work demonstrates that MXene catalysts can be mediated through the optimization of both QDs sizes and functional groups for efficient ammonia production at room temperature. [ABSTRACT FROM AUTHOR]

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Nanozyme-based colorimetry was suggested to be a rapid method for biomarker (e.g. glutathione) detection, but this method suffers from lack of efficiency and low-toxicity nanozymes till now. Herein, quantum dots of TiO2 loaded on carbon (TiO2/C-QDs) oxidase-like nanozymes were prepared via a hydrothermal treatment of tiny and few-layered Ti3C2Tx MXene nanosheets, which possess abundant thermodynamic metastable Ti atoms on MXene margins as raw materials for the preparation of TiO2/C-QDs. The oxygen vacancy in TiO2 on the surface of the carbon matrix can facilitate O2 adsorption in the solution and generate reactive oxygen species (ROS), thereby quickly oxidizing 3,3′,5,5′-tetramethylbenzidine (TMB) to its oxidized form (TMBox) in the absence of H2O2. After adding glutathione (GSH), TMBox was able to be restored to TMB, which resulted in a corresponding decrease in the UV-vis absorbance value at 652 nm. Furthermore, this assay possesses good selectivity, excellent specificity and high sensitivity (limit of detection: 0.2 μM), which made it possible to efficiently detect GSH in complex biological samples such as human serum. [ABSTRACT FROM AUTHOR]

Electrochemistry belongs to an important branch of chemistry that deals with the chemical changes produced by electricity and the production of electricity by chemical changes. Therefore, it can not only act a powerful tool for materials synthesis, but also offer an effective platform for sensing and catalysis. As extraordinary zero‐dimensional materials, carbon‐based quantum dots (CQDs) have been attracting tremendous attention due to their excellent properties such as good chemical stability, environmental friendliness, nontoxicity and abundant resources. Compared with the traditional methods for the preparation of CQDs, electrochemical (EC) methods offer advantages of simple instrumentation, mild reaction conditions, low cost and mass production. In return, CQDs could provide cost‐effective, environmentally friendly, biocompatible, stable and easily‐functionalizable probes, modifiers and catalysts for EC sensing. However, no specific review has been presented to systematically summarize both aspects until now. In this review, the EC preparation methods of CQDs are critically discussed focusing on CQDs. We further emphasize the applications of CQDs in EC sensors, electrocatalysis, biofuel cells and EC flexible devices. This review will further the experimental and theoretical understanding of the challenges and future prospective in this field, open new directions on exploring new advanced CQDs in EC to meet the high demands in diverse applications. [ABSTRACT FROM AUTHOR]

The design and development of excellent microwave absorption (MA) material is significant for healthcare, electronic, and security industries. Herein, a sophisticated composite with the advantages of large interlayer space, nanoparticles with small size, and hierarchical nanostructure (core@shell@void@shell configuration) simultaneously is demonstrated for the first time. Such unique SiO2@TiO2 nanoparticle was fabricated via a multi-step process. Associating maximum reflection loss value can reach –35.2 dB in certain frequency of 11 GHz and thickness of 3.0 mm. Small-sized TiO2 nanoparticles (about 6 nm) in first coating and large gap between TiO2 coating layers are significantly critical for the superior MA performance. Our work points a new direction to rationally construct high-performance microwave absorber. [ABSTRACT FROM AUTHOR]

The metal-induced FL quenching of two-dimensional material-derived quantum dots (2D-QDs) has been playing vital roles in optical sensing recently; however, the metal type and concentration are usually chosen arbitrarily based on the maximum FL decrease although several metals may offer similar FL quenching effects towards the same 2D-QDs. Thus, a rational strategy was urgently needed to discover more efficient metal-mediated FL system for further applications. Taking boron nitride QDs (BNQDs) as a promising 2D-QD model, it was discovered that both Fe3+ and Cu2+ could quench their FL, which could be further switched on and off upon the addition of pyrophosphate and alkaline phosphatase, respectively. By comparing the percentage of FL quenching and recovery of BNQDs, it was rationally calculated that 300 μM Fe3+-mediated FL quenching of BNQDs paved a more efficient way for the sensitive and selective assay of ALP. Quantitative measurement of the ALP activity can be achieved with a low limit of detection of 0.8 U L−1 (S/N ≥ 3) in a wide range between 2 and 200 U L−1. In addition, the aforementioned ensemble could be exploited to newly construct a 2D-QD-based “INH” logic gate. This approach possessed many superiorities i.e. low cost, simplicity, and high sensitivity. [ABSTRACT FROM AUTHOR]

Abstract: Vanadium oxide (VOx) nanomaterials have been attracting great attention recently due to their outstanding physicochemical properties. Engineering VOx into quantum dots (QDs) should bring new properties and potential for applications, but has not been reported until now. Meanwhile, the shortcomings in QDs synthesis such as needing high temperature and expensive instruments still need to be overcome. Herein, VOxQDs were generated via a simple ultrasonic and agitation strategy at room temperature using DMSO as both solvent and exfoliation agent. The VOx QDs exhibited blue fluorescence under 365 nm ultraviolet irradiation. They were with good monodispersion, narrow size distribution and average particle size of 3.3±0.3 nm. The VOxQDs can be used as a competitive fluorescent sensing probe for label‐free specific detection of Fe3+ and PPi based on the ON‐OFF or ON‐OFF‐ON fluorescent principle, respectively. Moreover, the antibacterial activity of the as‐prepared VOxQDs was found, which could damage the cell membrane and inhibit the bacterial growth of both Gram (+) (Staphylococcus aureus) and Gram (−) (Escherichia coli) bacteria, respectively. [ABSTRACT FROM AUTHOR]

MoOx quantum dots (QDs) were prepared using a one-step stirring treatment of molybdenum trioxide (MoO3) powder in dimethyl sulfoxide (DMSO). Besides their highly sensitive label-free metal ion and pyrophosphate sensing, the antibacterial activity of the as-prepared MoOx QDs was discovered for the first time. [ABSTRACT FROM AUTHOR]

A one-step method using under-liquid laser machining (ULLM) is proposed for fabrication of microdimples on a cemented carbide surface with a wear-resistant amphiphobic property. The influence of laser processing parameters on the depth, width, and surface roughness (Ra) of the microstructures were investigated through single-factor experiments. On the basis of single-factor experiments, multiobjective optimization was carried out so that a desired surface morphology can be achieved. The model describing the relationships between laser processing parameters and corresponding responses was developed based on response surface methodology (RSM), and the adequacy of the model was assessed by analysis of variance (ANOVA) and verified experimentally. Subsequently, the desired microstructure arrays were then fabricated with the optimal processing parameters. Finally, the wear-resistant behaviors were comparatively studied for two kinds of amphiphobic surfaces by rubbing multiple times using 1000 grit metallographic sandpaper. The textured surface fabricated using the ULLM method exhibits excellent mechanical rubbing resistance as it maintains its amphiphobic character even after rubbing 300 m under the pressure of 2.4 MPa. This facile and low-cost method can be not only easily extended to other materials but also applied to fabricate amphiphobic surfaces with wear-resistance and self-healing properties. [ABSTRACT FROM AUTHOR]

To achieve the energy‐effective ammonia (NH3) production via the ambient‐condition electrochemical N2 reduction reaction (NRR), it is vital to ingeniously design an efficient electrocatalyst assembling the features of abundant surface deficiency, good dispersibility, high conductivity, and large surface specific area (SSA) via a simple way. Inspired by the fact that the MXene contains thermodynamically metastable marginal transition metal atoms, the oxygen‐vacancy‐rich TiO2 nanoparticles (NPs) in situ grown on the Ti3C2Tx nanosheets (TiO2/Ti3C2Tx) are prepared via a one‐step ethanol‐thermal treatment of the Ti3C2Tx MXene. The oxygen vacancies act as the main active sites for the NH3 synthesis. The highly conductive interior untreated Ti3C2Tx nanosheets could not only facilitate the electron transport but also avoid the self‐aggregation of the TiO2 NPs. Meanwhile, the TiO2 NPs generation could enhance the SSA of the Ti3C2Tx in return. Accordingly, the as‐prepared electrocatalyst exhibits an NH3 yield of 32.17 µg h−1 mg−1cat. at −0.55 V versus reversible hydrogen electrode (RHE) and a remarkable Faradaic efficiency of 16.07% at −0.45 V versus RHE in 0.1 m HCl, placing it as one of the most promising NRR electrocatalysts. Moreover, the density functional theory calculations confirm the lowest NRR energy barrier (0.40 eV) of TiO2 (101)/Ti3C2Tx compared with Ti3C2Tx or TiO2 (101) alone. [ABSTRACT FROM AUTHOR]

MXene‐derived quantum dots (MQDs) have begun to attract much attention recently, but their most attractive features (i.e., optical properties) are still explored less than expected. In the present work, Ti3C2Tx MQDs with solvent‐determined optical characteristics and size distributions are prepared through solvothermal treatment of Ti3C2Tx nanosheets in various solvents. White‐emitting photoluminescence (PL) under 365 nm UV irradiation is obtained in dimethyl sulfoxide (DMSO), while blue in dimethylformamide (DMF) and ethanol, respectively. Moreover, the average diameters and quantum yields of the MQDs are 3.3 ± 0.2 nm and 10.7%; 2.5 ± 0.2 nm and 6.9%; as well as 1.8 ± 0.1 nm and 4.1% in DMF, ethanol, and DMSO, respectively. Interestingly, among a variety of metal ions, Fe3+ shows specific quenching effect toward the PL of the MQDs in DMF rather than in the other two. Moreover, electrochemiluminescence of the MQDs is observed using persulfate as coreactant for the first time. The possible mechanisms are discussed based on the combined influences of polarity, oxidation effect, and boiling point of the different solvents and the various characterizations. White/blue‐emitting photoluminescence (PL) of MXene‐derived quantum dots (MQDs) is obtained depending on the varied solvents in solvothermal treatment of bulk Ti3C2Tx MXene. Fe3+ shows specific quenching effect toward the PL of the MQDs in dimethylformamide rather than in others. Moreover, electrochemiluminescence of the MQDs is for the first time observed using persulfate as coreactant. [ABSTRACT FROM AUTHOR]

Herein, green-fluorescent N-doped carbon quantum dots (N-CQDs) with quantum yield of 30.6% were prepared via a simple bottom-up electrochemical (EC) method using the mixtures of pyrocatechol and ethylenediamine as both precursors and electrolytes. The ON-OFF fluorescence (FL) principle that the FL intensity of the N-CQDs was quenched in the presence of Fe 3+ was further extended to the ON-OFF-ON and ON-OFF-ON-OFF ones for pyrophosphate anions (PPi) and alkaline phosphatase (ALP) detection, respectively, based on the specific competitive interaction of N-CQDs with Fe 3+ and PPi and the hydrolysis of PPi in the presence ALP. Under the optimized conditions, limit of detection (LOD) of 1.2 μM and 0.5 μM were achieved for assays of Fe 3+ and PPi, respectively. Meanwhile, measurable evaluation of ALP activity was reached in a wide range from 5 to 360 U/L with a LOD of 1.1 U/L. The as-proposed sensors showed many advantages including label free, rapid, simple, low-cost, high sensitive, which has great promising application potential in vivo and in vitro clinical diagnosis and will promote the application of EC derived carbon nanomaterials. [ABSTRACT FROM AUTHOR]

In this study, SiO 2 Quantum Dots were produced by a simple acid-base hydrothermal treatment method using the widely available and low cost palygorskite as silicon source. The characterization results proved that the prepared SiO 2 Quantum Dots have good crystal form, excellent dispersion and stability, with an average particle diameter of 1.8 ± 0.1 nm. Since the fluorescence intensity of the SiO 2 Quantum Dots can be quenched in the presence of Fe3+, the SiO 2 Quantum Dots was used for specific ferric ion detection. And this fluorescence change phenomenon is mainly attributed to the electron transfer mechanism integrated with filter effect. Moreover, the result shows that SiO 2 Quantum Dots showed high potential applicability in the field of biological cells due to its low cytotoxicity. • SiO2 QDs were produced by simple acid-base hydrothermal method using palygorskite". • "The electron transfer between ions and SiO2 QDs makes QDs aggregate and PL quenches. • The as-prepared SiO 2 QDs can be used for specific detection of Fe3+. [ABSTRACT FROM AUTHOR]

Soil salinization is a major abiotic factor threatening rapeseed yields and quality worldwide, yet the adaptive mechanisms underlying salt resistance in rapeseed are not clear. Therefore, this study aimed to explore the differences in growth potential, sodium (Na + ) retention in different plant tissues, and transport patterns between salt-tolerant (HY9) and salt-sensitive (XY15) rapeseed genotypes, which cultivated in Hoagland's nutrient solution in either the with or without of 150 mM NaCl stress. The results showed that the inhibition of growth-related parameters of the XY15 genotype was higher than those of the HY9 in response to salt stress. The XY15 had lower photosynthesis, chloroplast disintegration, and pigment content but higher oxidative damage than the HY9. Under NaCl treatment, the proline content in the root of HY9 variety increased by 8.47-fold, surpassing XY15 (5.41-fold). Under salt stress, the HY9 maintained lower Na + content, while higher K + content and exhibited a relatively abundant K + /Na + ratio in root and leaf. HY9 also had lower Na + absorption, Na + concentration in xylem sap, and Na + transfer factor than XY15. Moreover, more Na + contents were accumulated in the root cell wall of HY9 with higher pectin content and pectin methylesterase (PME) activity than XY15. Collectively, our results showed that salt-tolerant varieties absorbed lower Na + and retained more Na + in the root cell wall (carboxyl group in pectin) to avoid leaf salt toxicity and induced higher proline accumulation as a defense and antioxidant system, resulting in higher resistance to salt stress, which provides the theoretical basis for screening salt resistant cultivars., (© 2024 Scandinavian Plant Physiology Society.)