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Determination of Hg2+ is crucial as its high toxicity poses a potential serious threat to food and the environment. Therefore, it is urgent to explore a portable, cost-effective, and visual approach to monitor Hg2+. Herein, ratiometric-constructed dual-emissive carbon dots (P-R-CDs) with dual emissions at 440 and 575 nm were fabricated by blue CDs and orange CDs for visual quantitative detection of Hg2+. The vivid colorimetric sensing can be achieved by quantitative quenching blue emission with Hg2+ and relative stable orange emission. Consecutive fluorescent color transformation with elimination of blue emission by Hg2+ embodied visible distinguishable determination of Hg2+, with a detection limit of 2.9 nM. Furthermore, a smartphone-supported visual sensing platform was established for the determination of Hg2+ by capturing and identifying the RGB value of the variation precisely. The smartphone assistant detection greatly promoted the effectiveness of detection and provided promising on-site application in real samples. The recoveries in real water and food samples revealed the excellent environmental tolerance of P-R-CDs, which represented a prospective application utility for quantitative monitoring of Hg2+ in food and the environment. [ABSTRACT FROM AUTHOR]

Enzyme biofuel cells (EBFCs) can convert chemical or biochemical energy in fuel into electrical energy, and therefore have received widespread attention. EBFCs have advantages that traditional fuel cells cannot match, such as a wide range of fuel sources, environmental friendliness, and mild reaction conditions. At present, research on EBFCs mainly focuses on two aspects: one is the use of nanomaterials with excellent properties to construct high-performance EBFCs, and the other is self-powered sensors based on EBFCs. This article reviews the applied nanomaterials based on the working principle of EBFCs, analyzes the design ideas of self-powered sensors based on enzyme biofuel cells, and looks forward to their future research directions and application prospects. This article also points out the key properties of nanomaterials in EBFCs, such as electronic conductivity, biocompatibility, and catalytic activity. And the research on EBFCs is classified according to different research goals, such as improving battery efficiency, expanding the fuel range, and achieving self-powered sensors. [ABSTRACT FROM AUTHOR]

The NbTiAlZrHfTaMoW refractory high-entropy alloy (RHEA) system with the structure of the B2 matrix (antiphase domains) and antiphase domain boundaries was firstly developed. We conducted the mechanical properties of the RHEAs at 298 K, 1023 K, 1123 K, and 1223 K, as well as typical deformation characteristics. The RHEAs with low density (7.41~7.51 g/cm3) have excellent compressive-specific yield strength ( σ YS / ρ) at 1023 K (~131 MPa·cm3/g) and 1123 K (~104.2 MPa·cm3/g), respectively, which are far superior to most typical RHEAs. And, they still keep appropriate plastic deformability at room temperature (ε > 0.35). The superior specific yield strengths are mainly attributed to the solid solution strengthening induced by the Zr element. The formation of the dislocation slip bands with [111](10 1 _ ) and [111](11 2 _ ) directions and their interaction provide considerable plastic deformation capability. Meanwhile, dynamic recrystallization and dislocation annihilation accelerate the continuous softening after yielding at 1123 K. [ABSTRACT FROM AUTHOR]

Psathyrostachys huashanica Keng (2n = 2x = 14, NsNs) is an excellent gene resource for wheat breeding, which is characterized by early maturity, low plant height, and disease resistance. The wheat-P. huashanica derivatives were created by the elite genes of P. huashanica and permeate into common wheat through hybridization. Among them, a long-glume material 20JH1155 was identified, with larger grains and longer spike than its parents. In the present study, the methods of cytological observation, GISH, and sequential FISH analysis showed that 20JH1155 contained 21 pairs of wheat chromosomes and a pair of P. huashanica. There were some differences in 5A and 7B chromosomes between 20JH1155 and parental wheat 7182. Molecular marker, FISH, and sequence cloning indicated 20JH1155 alien chromosomes were 3Ns of P. huashanica. In addition, differentially expressed genes during immature spikelet development of 20JH1155 and 7182 and predicted transcription factors were obtained by transcriptome sequencing. Moreover, a total of 7 makers derived from Ph#3Ns were developed from transcriptome data. Taken together, the wheat-P. huashanica derived line 20JH1155 provides a new horizon on distant hybridization of wheat and accelerates the utilization of genes of P. huashanica. [ABSTRACT FROM AUTHOR]

Mercury (Hg) is the most toxic heavy metal and can lead to severe irreversible injury to human health and serious pollution. It is of great significance to explore precise and facile detection methods for preventing environmental pollution and ecological problems. Herein, silicon-doped carbon dots (Si-CDs) with bright blue emission were fabricated and employed as a fluorescent probe for the quantitative detection of Hg2+. Possessing high photostability and excellent solubility in water, the Si-CDs exhibit an efficient response to Hg2+ by a "on–off" switching strategy. As a sensing probe, Si-CDs exhibit a good linear relationship with Hg2+ in the concentration range of 0.008–0.4 μM with a limit of detection of 33 nM. Moreover, the proposed method was successfully applied to monitor Hg2+ in different real water samples with satisfactory recoveries of 96.2%–99.5%, demonstrating their excellent accuracy and environment tolerance. Notably, the Si-CD powder obtained by lyophilization can visualize latent fingerprints with second-level details. The results serve to underscore how CDs designed for multiple applications in detection can be exploited to provide promising multi-functional fluorescent materials. [ABSTRACT FROM AUTHOR]

According to the effect of valence electron concentration (VEC) on the phase evolution of high‐entropy alloys (HEAs), Fe75.7−xCrxNi15.1Al4.6Ti4.6 (at%, x = 17.1, 18.9, 20.6, 22.3, and 25.3) HEAs are designed. Effects of the Cr addition on the microstructure and tensile properties are investigated systemically. As the Cr/Fe ratio increases (i.e., decreasing VEC), there is a phase transition from face‐centered‐cubic (FCC) to body‐centered‐cubic (BCC) and Heusler‐type β′ ‐Ni2TiAl (L21). When x is between 17.1 and 22.3, the alloys, with the mixed structure of the FCC and BCC/L21 phases, behave like composites with a sharp increase in strength but reduced ductility. When x = 25.3, the alloy, with only BCC/L21 phases, becomes extremely brittle. Specifically, Fe56.8Cr18.9Ni15.1Al4.6Ti4.6 exhibits a good combination of a high strength of 1142 MPa and an elongation strain of 9.5%. The excellent tensile properties of this alloy are attributed to the synergetic effects of a soft FCC phase, a hard BCC phase, and the uniform distribution of high‐density L21 nanoparticles in BCC matrix. The phase‐evolution principle is delineated by parameters of the VEC and the atomic size difference (δ), and the strengthening mechanism is well discussed. These findings offer a guidance for the development of BCC/L21‐containing HEAs for practical applications. [ABSTRACT FROM AUTHOR]

It remains challenging to develop low-cost body-centered cubic (BCC) high-entropy alloys (HEAs) with superior mechanical properties. In this work, we investigated the microstructure and mechanical properties of BCC FexCrNiAl0.5Ti0.5 HEAs containing L21 nanocrystals. With increasing the Fe content from Fe2 to Fe4 and Fe6, the formation of a big blocky L21 phase and a σ phase can be fully suppressed, and the size and fraction of the L21 crystals also decrease. Fe4 and Fe6 HEAs exhibit an optimized dual-phase microstructure with high-density L21 nanocrystals homogeneously distributed in the BCC matrix. Fe4 and Fe6 HEAs show high strength and do not fracture even at a large compressive strain of 70%, exhibiting the best combination of strength and fracture strain among all the reported BCC HEAs with nanocrystals. The superior mechanical properties of Fe4 and Fe6 HEAs are attributed to the optimized microstructure. These findings promote the development of low-cost HEAs with superior mechanical properties. [ABSTRACT FROM AUTHOR]

As the most toxic heavy metal, mercury (Hg) has been considered as the greatest environmental threat and it reach ubiquitous in industrial waste water and extended to environment. The detection of Hg2+ in environmental water is a crucial work for both protecting the environment and human health. Colorimetric assay exhibits visual discriminating and simple readout. This work presents the selective sensing of metal ion (Hg2+) by silver particles (Ag NPs), which were functionalized by galactosamine and synthesized via simple one pot method, with the average particle diameter of 18.75±0.49 nm. The limit of detection (LOD) was calculated as low as 7.92 nM. The colorimetric probe can also be performed in real water sample with good selectivity, and recovery was found to be 95–102 %, indicating can be used for on‐line determination of Hg2+ in the complex aqueous solutions. Additionally, the good catalytic performance of Ag NPs was demonstrated by hydrogenation of p‐nitrophenol and potassium ferricyanide in water samples. [ABSTRACT FROM AUTHOR]

In this work, a series of MoxCo1−xP2/MWCNT (x = 0.25, 0.29 and 0.33) composite electrocatalysts have been designed and successfully fabricated, and their utility as remarkable, active and stable electrocatalysts is reported for the first time. The MoxCo1−xP2/MWCNT composite electrocatalysts with controllable morphology and composition are created by changing the molar ratios of Mo : Co precursors. Mo0.29Co0.71P2/MWCNTs exhibits the best hydrogen evolution (HER) and oxygen evolution reaction (OER) performance with low overpotentials of 85 and 220 mV in 1.0 M KOH, respectively. Impressively, a cell voltage of 1.48 V at a current density of 10 mA cm−2 for overall water splitting has been realized by using Mo0.29Co0.71P2/MWCNTs as both the cathode and anode material, which is one of the lowest potentials for practical overall water splitting. Experimental and density functional theory results suggest that such excellent electrocatalytic performance may stem from the synergistic effect between Mo0.29Co0.71P2 and MWCNTs. [ABSTRACT FROM AUTHOR]

Understanding cavity-interface interaction is crucial in designing high-strength, radiation-tolerant nanocomposites. Here, bubbles near the Cu–Nb interface in Nb could be absorbed by Cu voids wetting the interface due to the high system energy difference produced by the huge pressure difference between the bubbles and voids and high mobility of bubbles, and no bubble-denuded zone forms owing to fast Brownian motion of bubbles, which keeps bubbles distributed homogeneously. However, owing to the low system energy difference generated by the low internal pressure difference and low mobility, voids near the Cu–Nb interface in Nb would simply coalesce with Cu voids wetting the interface, leading to the void-interface wetting to crossing transition and the formation of void-denuded zones due to the negligible migration of internal Nb voids. [ABSTRACT FROM AUTHOR]

BACKGROUND: Silica‐based adsorbents have shown huge potential and bright perspective in adsorptive removal of antibiotic contaminants for water remediation. To further simplify the synthesis process, stabilize the doped metal and improve the adsorption capacity, a highly‐effective metal iron‐doped mesoporous silica (meso‐Fe(III)/SiO2) adsorbent was in situ one‐step synthesized under the strategy of using metal‐based ionic liquid [(C12H25)3NCH3]FeCl4 as template and iron source. RESULTS: Iron(III) species have been found highly dispersed in the confined space of meso‐SiO2 without pore blocking. Compared with the prototype and Fe‐impregnate meso‐SiO2 adsorbents, the meso‐Fe(III)/SiO2 exhibited significantly enhanced adsorptive removal of 95.6% and 93.8% for tetracycline (TC) and levofloxacin (LOF), respectively. The adsorption was controlled by diffusion processes and well described by pseudo‐second‐order kinetics equation and Langmuir isotherm model. Solution pH, co‐existing Na+ and Ca2+ exhibited significant impact on the adsorption process which is strongly related to π‐complexation, hydrophobic effect and electrostatic interactions. CONCLUSION: The strategy of metal‐based ionic liquid assisted synthesis provide a promising approach to design and develop highly‐stable metal‐supported adsorbents. Furthermore, the excellent adsorption performance indicated the potential application of this meso‐Fe(III)/SiO2 in the removal of antibiotics from aqueous solutions. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In this paper, the carbon-doped boron nitride nanoplate (C-BNNP) was prepared by pyrolyzing the precursor under N 2 and served as an excellent adsorbent for removal of Rhodamine B (RhB). The structure and composition of C-BNNP were characterized and its adsorption behavior for RhB was investigated. Compared with boron nitride nanoplate (BNNP) which was synthesized under NH 3 , C-BNNP displayed an enhancement of the adsorption capacity for RhB (833 mg/g). The adsorption activity was comprehensibly studied by kinetics, isotherm and thermodynamics. The adsorption kinetics followed pseudo-second-order model. The equilibrium adsorption data agreed well with the Langmuir isotherm. And the thermodynamics indicated that the adsorption process was a spontaneous, exothermic and physisorption process. In addition, the density functional theory was proposed that doping carbon in the BNNP decreased the chemical hardness of the adsorbent and enhanced the adsorption capacity of C-BNNP for RhB. [ABSTRACT FROM AUTHOR]

Activated metal-free boron nitride (BN) adsorbent has been prepared by a surfactant assisted regulation strategy. By tuning the variety of surfactants (such as P123, PVP, F127), usage and reaction temperature, the adsorptive performance of activated BN was optimized. The optimized BN-P123 adsorbent displays porous structure with a high surface area about 1185 m2/g and exhibits excellent adsorptive desulfurization activity for dibenzothiophene (45.7 mg S/g adsorbent for 500 ppmw sulfur model oil), which is comparable or even superior to the state-of-the-art adsorbent. Additionally, this activated BN-P123 could realize the ultra-deep desulfurization through adsorptive process to reach the latest international standard (less than 10 ppmw). Considering the nontoxic metal-free feature and the excellent adsorption performance, the obtained activated BN-P123 may be a powerful candidate to meet the requirements of potential industrial applications. © 2017 American Institute of Chemical Engineers AIChE J, 63: 3463-3469, 2017 [ABSTRACT FROM AUTHOR]

The performance of graphene-analogue molybdenum disulfide (G-MoS2) as an adsorbent for removal of organic contaminant tetracycline from aqueous solution was studied systematically. The synthetic G-MoS2 showed much better adsorption ability than the commercial MoS2 with more than 90% of tetracycline removal. The kinetics data agreed well with the pseudo-second order model, and the equilibrium was obtained within 16 h. Langmuir isotherm model provided the best fit to the equilibrium data of tetracycline adsorption than Freundlich and Tempkin models. The adsorption was a spontaneous and endothermic process deduced by the thermodynamic analysis. Adsorption of tetracycline on G-MoS2 was partly dependent on pH values, but strongly relied on ionic strength. The proposed mechanism was probably synergetic π-π dispersion, hydrophobic effect, and electrostatic interaction. © 2017 American Institute of Chemical Engineers Environ Prog, 36: 815-821, 2017 [ABSTRACT FROM AUTHOR]

h-BN has been demonstrated to be able to exhibit adsorptive desulfurization from fuel. In order to further optimize the adsorption capacities to meet the potential industrial applications, tuning the nanostructure of BN was taken into account. In this work, we demonstrated that cyanamide, dicyandiamide, and melamine as different nitrogen precursors for synthesizing BN could tune the BN nanoarchitectures. The high performance BN prepared with melamine presented a ribbon-like structure which was assembled with porous nanosheets. This kind of nanoarchitecture with exposed BN sharp edges and a porous structure can be constructed on the BN surface. The large number of low coordinated atoms at the exposed sharp edges and along the edges of the pores could build powerful interaction with sulfide, which was believed to be responsible for the advanced adsorption capacity. The prepared BN with melamine as nitrogen precursors displayed remarkable adsorption performance for DBT (40.2 mg S per g adsorbent for 500 ppm sulfur model oil and 57.5 mg S per g adsorbent according to the Langmuir isotherm model). To the best of our knowledge, it is the highest adsorption capacities reported so far for the adsorptive desulfurization. It is also noteworthy to mention that even for refractory sulfur compound 4,6-DMDBT, the prepared BN still showed high adsorption performance. [ABSTRACT FROM AUTHOR]