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[Display omitted] • An acid–induced dispersive liquid–liquid microextraction is developed. • Analytes are extracted by in situ formation of deep eutectic solvents with formed fatty acids. • The method is successfully used for detection of bisphenol A and alkylphenols. • The method is simple, rapid, sensitive, low cost, and environmentally friendly. • The new method expands the application pathway and scope of deep eutectic solvents. This study describes the development of an acid induced dispersive liquid–liquid microextraction method based on the in situ formation of hydrophobic deep eutectic solvents for the extraction of bisphenol A and alkylphenols from environmental water and beverage samples. Hydrochloric acid altered the hydrophilic-hydrophobic state of fatty acid salts to obtain hydrophobic fatty acids, which formed hydrophobic deep eutectic solvents with analytes in situ to extract the analytes. Under optimized conditions, the limits of detection and limits of quantitation were 0.03–0.1 μg L-1 and 0.12–0.3 μg L-1, the intraday and interday relative standard deviations were less than 3.9 %, and the enrichment factor was 29–32. The recoveries of bisphenol A and alkylphenols were 95.9–104.9 % and 86.9–105.0 %, respectively. The extraction process used only hydrochloric acid and fatty acid salts, and the extraction process required less than 1 min. This method has the advantages of simplicity, speed, low cost and environmental friendliness. [ABSTRACT FROM AUTHOR]

Aliphatic aldehydes are a class of organic compounds containing aldehyde groups, which are widespread, and closely related to people's daily life and health. In this work, a series of terpenes based hydrophobic deep eutectic solvents were designed and synthesized using hexafluoroisopropanol as hydrogen bond donor and menthol/thymol as hydrogen bond acceptor. Then they are used as extraction solvent in dispersive liquid-liquid microextraction for extracting and determining seven aliphatic aldehydes from drinking water and alcoholic beverage combined with high performance liquid chromatography-ultraviolet. Due to the fact that these hydrophobic deep eutectic solvents are liquid at the room temperature, a density greater than that of water, a lower viscosity (≤26.10 mPa s, 25 °C), after extraction and centrifugation, the microvolume DES-rich phase in the bottom is convenient for collection and direct analysis without further dissolution or dilution with organic solvents. Some factors affecting the extraction recovery were optimized by one-variable-at-a-time and response surface methodology. Under the optimal conditions, the enrichment factors for the seven aliphatic aldehydes were 48–56. The method had good performance: linear ranges of 1.0–200, 0.5–200, 0.2–200, 0.4–400, 1.0–400, 0.4–400 and 0.4–400 μg L−1 for seven aliphatic aldehydes (r 2 ≥ 0.9949), limits of detection of 0.1–0.5 μg L−1, intra-day and inter-day precisions <4.9%. The recoveries of seven aliphatic aldehydes ranged from 76.0 to 119.0%. The proposed dispersive liquid-liquid microextraction method is simple, rapid, highly efficient, and green, which effectively reduces the amount of toxic chemical reagents used and their impact on the environment. Rapid and efficient detection of aliphatic aldehydes helps ensure a healthy diet and has great application prospects in food safety analysis. [Display omitted] • Terpenes based HDESs with low viscosity and high density were designed and prepared. • A terpenes HDESs based DLLME was established for enrichment of aliphatic aldehydes. • The DES-rich phase in the bottom is easy to be collected and directly analyzed by HPLC. • The method is simple, rapid, effective and green for detecting aliphatic aldehydes. • The green profile of the method was assessed by AES and AGREE. [ABSTRACT FROM AUTHOR]

Ti 3 AlC 2 ceramic exhibits potential in Ag-based composite electrical contact materials, but its interface characteristic with Ag matrix remains unexplored. In this work, sessile drop experiment is carried out to investigate the high-temperature wetting behavior of molten Ag with Ti 3 AlC 2. Stable Ti 3 AlC 2 is hardly wetted by molten Ag below 1000 °C(contact angle of 148.5°), but the wettability of Ag/Ti 3 AlC 2 improves with the increasing temperature(final 14° at ∼1130 °C). In contrast, the Ti 3 C 2, a MXene with Al layer removed from its parent Ti 3 AlC 2 , exhibits inferior wettability with Ag(final 56.5° at ∼1130 °C). Wetting mechanism of Ag/Ti 3 AlC 2 is proposed on the basis of the interfacial structure and chemical composition. Increasing temperature accelerates dissociation of Ti 3 AlC 2 , and outward-escaping Al reacts with Ag to form interface layer with a composition of Ag 4.86 Ti 8.66 AlC 7.59 , Ag also diffuses along Ti 3 AlC 2 grain boundaries and forms gradient reactive products(Ag–Ti–Al–C), which promotes their wettability. Finally comprehensive properties of Ag/Ti 3 AlC 2 and Ag/Ti 3 C 2 are compared. Al–Ag interdiffusion slightly decreases the electrical conductivity of Ag/Ti 3 AlC 2 bulk material, but strengthen the interface bonding of composite and promote the viscosity of the molten pool, leading to the superior mechanical and anti-arc erosion properties. Absence of Al–Ag interdiffusion does remarkably improve the electrical conductivity of Ag/Ti 3 C 2 bulk materials, but lack of Al layer damages the mechanical core and wettability with Ag, resulting in a drastic decrease of anti-arco erosion property. [ABSTRACT FROM AUTHOR]

Along with the rapid development of diversified social media, WeChat has become a prevalent social tool in mainland China which allows users to connect and communicate with others spanning time and distance. Although a great deal of empirical literature has explored the antecedents of electronic word-of-mouth (e-WOM) and indicated that a link exists between social capital and e-WOM engagement, the specific dimensions of social capital are still rarely probed and investigated, especially in the mobile social media setting. The present research takes a social capital perspective and aims to systematically clarify three distinct dimensions of social capital, attitude towards e-WOM and their association with WeChat users' e-WOM engagement behaviors. The current research analyzes variables and their influence using structural equation modeling. The statistical sample was obtained from 365 young people who have used WeChat in mainland China. The obtained results demonstrate that WeChat usage intensity can positively influence social interaction ties, social trust, and perceived homophily. Additionally, social interaction ties, social trust, and perceived homophily can positively predict WeChat users' e-WOM engagement. Furthermore, attitude towards e-WOM can partially mediate the effect of social capital on e-WOM engagement. These new findings may enrich the existing research body of social capital theory and provide fresh insights for scholars and managers to further understand individuals' attitudes and e-WOM engagement behaviors in the contemporary new media environment. • WeChat usage intensity can positively influence social interaction ties, social trust, and perceived homophily. • Social interaction ties, social trust, and perceived homophily can positively predict WeChat users' e-WOM engagement. • Attitude towards e-WOM can partially mediate the effect of social capital on e-WOM engagement. [ABSTRACT FROM AUTHOR]

• One-step derivatization and TC-VA-LLME-SFDES method was developed. • Hydrophobic DESs were used as both reducing agent and extraction solvent. • Only 2 min was needed for derivatization and extraction process. • The method was applied for analysis of total Fe in water and food samples. • The method opened up the application of solid DESs in LLME technique. In our work, hydrophobic thymol-based deep eutectic solvents (DESs) with strong reducibility, a lower density than water, and a slightly higher melting point than room temperature were synthesized. Based on these solid DESs, one-step derivatization and temperature-controlled vortex-assisted liquid-liquid microextraction based on the solidification of a floating DES (TC-VA-LLME-SFDES) via UV–Vis spectrophotometry for the rapid determination of total iron was developed. The derivatization and TC-VA-LLME were carried out simultaneously by the addition of DES as both the reducing agent and extraction solvent. After optimization, the calibration curve (5–250 μg L−1, R2 = 0.9982), limit of detection (1.5 μg L−1), limit of quantitation (5.0 μg L−1), precision (≤4.0%) and enrichment factor (92) was obtained. This method was applied for the determination of total iron in water and food samples with satisfactory recoveries (85.4–106.2%). One-step derivatization and TC-VA-LLME only required 2 min. Furthermore, this method opened up the application of solid DESs in liquid–liquid microextraction. [ABSTRACT FROM AUTHOR]

Ti 3 AlC 2 ceramic-reinforced Ag matrix composites exhibit superior electrical contact performance. However, the arc corrosion mechanism of the Ti 3 AlC 2 reinforcing phase has not been clarified; in particular, the intrinsic relationship between the microstructure and mechanical properties needs to be further explored. In this work, by combining micro/nano-indentation, microstructural and chemical composition analysis, COMSOL simulation, and accelerated aging experiments, the relationship among phase transition, microstructural evolution, and macro/micro/nano-mechanical property changes were compared and analyzed. The cycles of arc discharge produced heat accumulation, which was transmitted from the contact surface to the interior in a gradient (divided into Areas α , β , γ). Changes in the structural dissociation, oxidation, and interfacial bonding of Ti 3 AlC 2 with the Ag matrix resulted in different micro/nano-mechanical properties in these areas in terms of micro-hardness, nano-hardness, modulus, and elastic-plasticity. These findings demonstrate the key role of the phase and microstructural evolution of Ti 3 AlC 2 on the mechanical properties of such composites while also providing a mechanical theoretical basis for future structural design and interfacial optimization of eco-friendly Ti 3 AlC 2 -reinforcing phases in Ag matrix composites. [ABSTRACT FROM AUTHOR]

• DESs with low viscosity, density and melting point near room temperature were designed and used. • A centrifugation-free AA-LLME-SFDES method was developed. • Placket-burman design and central composite design were used for the method optimization. • This method was used for simultaneous analysis of bisphenols and PAHs in 15 tea infusions samples. • This method may be developed as a fully automated AA-LLME method. Deep eutectic solvents (DESs) are a new class of green "designer solvent"; its physicochemical properties can be easily tuned by adjusting DES′ constituents, chemical ratio and water content. In this study, three hydrophobic DESs with low viscosity, low density, and melting points close to room temperature were designed and synthesized. Based on these DESs, an air-assisted liquid–liquid microextraction technique was developed based on the solidification of floating DESs for the simultaneous determination of bisphenols and polycyclic aromatic hydrocarbons (PAHs) via HPLC. The microextraction parameters were optimized via the Plackett-Burman design and response surface methodologies. The method shows satisfactory linearity (R2 ≥ 0.9928), a low limit of detection (0.16–0.75 μg L−1) and satisfactory precision (≤2.3%), and was successfully applied for the simultaneous determination of bisphenols and PAHs from tea infusions with satisfactory recoveries (82.0–116.6%). This method is simple, rapid, economical, environmentally compatible, dispersive solvent-frees and centrifugation-free, and has promising applications in food safety. [ABSTRACT FROM AUTHOR]

A serious problem with integrated masonry linings ladle was that the ladle wall bricks were difficult to be partially replaced. Thus, the service life of the ladle was determined by the properties of ladle wall bricks. In this study, the new generation of MgO–Al 2 O 3 –C bricks with bauxite aggregates was tested in a ladle lining of an integrated steel ladle for 103 cycles, and the corroded microstructure of the used brick was investigated. A multilayered structure of bauxite aggregates could be observed in the used brick, which inhibited the slag penetration along the boundary of the magnesia aggregates and reduced the degree of the aggregates fall off from the used bricks. Besides, during the process of slag penetration, bauxite aggregates could melt into the slag, which increased the viscosity of the slag and weakened the penetration ability of the slag. The MgO–Al 2 O 3 –C bricks with bauxite addition could improve the service life of the ladle to a certain extent. [ABSTRACT FROM AUTHOR]

• The shallow and middle plough layers increased soil nutrient accumulation in 0–30 cm. • The deep plough layers increased soil nutrient accumulation in 30–50 cm soil layers. • The middle and deep plough layer promoted root development. • The shallow plough layers presented early maturity and premature senescence. • Soil plough layer 30 cm is conducive to the growth and development of cucumber. Perennial shallow tillage (PST) causes shallow plough layer thickness, deep plough sole layer thickness, and soil quality deterioration during intensive production. Cucumber is an economically important vegetable crop in the world, but it is generally sensitive to PST. Since little information is available regarding the response of soil quality and vegetable growth to PST, a greenhouse field experiment was conducted to investigate effects of plough layer (PL) thickness on soil nutrients, root characteristics, and crop productivity-related parameters in 2017 and 2018. The treatments considered were 10 (PL 10), 20 (PL 20), 30 (PL 30), 40 (PL 40), and 50 cm (PL 50) PLs. Overall, soil nutrients were mainly accumulated in 0–30 cm soil layer (55.6%–93.1%), and generally exhibited lower levels under PL 40 and PL 50 than under other PL treatments. The shallow PL treatments (PL 10 and PL 20) showed lower root volume density, root diameter and root length density, while the deep PL treatments (PL 40 and PL 50) showed higher specific root length. The medium PL treatment (PL 30) promoted root distribution in 0–30 cm soil layer as compared to other PL treatments. Moreover, the PL 30 treatment generally showed the highest values in not only crop productivity-related parameters (i.e. plant biomass and fruit yield) but also soil quality index. In summary, PL thickness played an important role in determining soil nutrient level, root growth and thereby crop yields. The optimal PL thickness for cucumber production was 30-cm, which could benefit not only crop growth but also soil quality. Solid and dotted lines indicate positive and negative correlations, respectively. * P < 0.05, ** P < 0.01. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • One-pot Solvent-free Synthesis strategy is proposed to prepare polycycloalkanes. • Novel NbOPO 4 nanosheets were fabricated to integrate alkylation and HDO processes. • Accessible Brønsted acidic sites of NbOPO 4 nanosheet favors alkylation. • Cocatalysts of NbOPO 4 and Ru/C accelerate the hydrodeoxygenation rate. • A renewable fuel of perhydrofluorene and dicyclohexylmethane was selectively prepared. Upgrading lignocellulose biomass to renewable fuels is essential to achieve carbon neutrality. However, the multiple synthetic, and purification steps as well as the employment of solvents in the production of renewable fuel inhibit the overall yields and cause the waste of energy and resources. Herein, a new catalytic strategy for one-pot solvent-free sequential synthesis (OSS) of perhydrofluorene and dicyclohexylmethane was developed from lignin-derivatives. A two-dimensional layered nanosheet niobium phosphate (NbOPO 4 -IB) catalyst was fabricated to efficiently integrate the alkylation of phenol and benzyl alcohol and sequential hydrodeoxygenation with a cocatalyst of Ru/C. The high crystalline NbOPO 4 phase and the lamellar morphology contributes to the large specific surface area to expose more active sites, especially more Brønsted acid sites. The NbOPO 4 -IB catalyst with a suitable Brønsted/Lewis acid ratio of 1.49 favors the selectivity of fuel precursors benzyl phenol in the alkylation and also provides the appropriate acid strength to promote hydrodeoxygenation activity. NbOPO 4 -IB also shows good reusability. Excessive phenol plays a vital role in promoting the alkylation reaction by dissolving the intermediates, and then into cyclohexane to enhance the H 2 dissolution in the hydrodeoxygenation. A possible mechanism of OSS from lignin-derivatives into polycycloalkanes over the cocatalysts was proposed. [ABSTRACT FROM AUTHOR]

Molecularly-imprinted polymers (MIPs), possessing tailor-made recognition sites, can specifically rebind to a target molecule in preference to analogous compounds. Molecular-imprinting technology is a powerful tool in the development of highly selective analytical methods. MIPs are especially good candidates as adsorbents for sample preparation, due to their high selectivity and their ability to pre-concentrate the analytes from a complex sample matrix. In this article, we review and discuss the recent applications of MIPs to sample preparation. We briefly discuss the principle and the synthesis of MIPs. We critically evaluate novel applications of MIPs in different formats, including solid-phase extraction, solid-phase microextraction, stir-bar sorptive extraction, and magnetic beads. We especially highlight new formats and microextraction methods. We then discuss the problems and the future expected trends in these research areas. [ABSTRACT FROM AUTHOR]

• CsMYB6 is an important component of the molecular network that regulates fruit spine and tubercule formation in cucumber. • CsMYB6 directly interacts with the key spine formation factor CsTTG1 to regulate spine development in cucumber. • CsMYB6 negatively regulates tubercule formation in cucumber by interacting with the C2H2-type zinc-finger protein CsTu. Cucumber fruit wart composed of tubercule and spine (trichome on fruit) is not only an important fruit quality trait in cucumber production, but also a well-studied model for plant cell-fate determination. The development of spine is closely related to the initiation and formation of tubercule. The spine differentiation regulator CsGL1 has been proved to be epistatic to the tubercule initiation factor CsTu , which is the only connection to be identified between spine and tubercule formations. Our previous studies found that the MIXTA-LIKE transcription factor CsMYB6 can suppress fruit spine initiation, which is independent of CsGL1. How the formation of spine and tubercule is regulated at the molecular level by CsMYB6 remains poorly understood. In this study, we characterized cucumber 35S : CsMYB6 transgenic plants, which displayed an obvious reduction in the number and size of fruit spines and tubecules. Molecular analyses showed that CsMYB6 directly interacted with the key spine formation factor CsTTG1 in regulating the formation of fruit spine, and CsTu in regulating the initiation of fruit tubercule, respectively. Based on these evidences, a novel regulatory network is proposed by which CsMYB6/CsTTG1 and CsMYB6/CsTu complexes play an important role in regulating epidermal development, including spine formation and tubercule initiation in cucumber. [ABSTRACT FROM AUTHOR]

• A method for separating FWA52 from foods by in situ formation of hydrophobic DES was established. • High concentration of inorganic salts and organic compounds had no effect on the separation process. • This strategy could be used directly to extract FWA52 at ultra-trace level (0.05 μg/L) • The established method was simple, rapid and environment-friendly. Fluorescent brightener 52 (FWA52) is a coumarin-based compound, and it is difficult to degrade owing to its high chemical stability. Up to now, several methods have been developed to extract and determine FWAs, but toxic, volatile and harmful organic solvents are often used. In this paper, a novel method for the extraction and analysis of FWA52 is proposed for the first time by in situ formation of hydrophobic deep eutectic solvent (DES) with parabens in aqueous solution. The effects of paraben structure, solution pH, system temperature, extractant dosage and initial FWA52 concentration on the extraction recovery were investigated systematically. It is shown that FWA52 can be extracted by 2-ethylhexyl 4-hydroxybenzoate at ultra-trace level (0.05 μg/L FWA52) at room temperature without using harmful organic solvents, and various coexisting inorganic ions and organic compounds have little effect on the extraction efficiency. Based on these results, a novel and simple strategy is developed for the accurate determination of FWA52 in water. It is found that under the optimal experimental conditions, the linear range of this method is 0.20~25 μg/L (R2 = 0.9995), and the detection limit and the quantity limit are 0.045 μg/L and 0.20 μg/L respectively. This method has been successfully applied for the determination of FWA52 in actual food samples and food contact materials, such as noodles, fish balls, mushroom and paper cups, with a recovery from 82 to 113% and a relative standard deviation (RSD) from 4.7 to 9.9%. In addition, the separation mechanism was investigated by FT-IR and 1H NMR, and was discussed from strong hydrogen bonding between FWA52 and 2-ethylhexyl 4-hydroxybenzoate and the formation of corresponding DES. [ABSTRACT FROM AUTHOR]

Highly efficient and selective separation of Cr (VI) is great of importance in environmental pollution control. In this study, a novel family of hydrophobic DESs has been designed and synthesized by mixing parabens and quaternary ammonium, and then used to extract heavy metal Cr (VI) from water phase and the content of Cr (VI) is measured by 1,5-diphenylcarbazide spectrophotometry. It is found that the hydrophobic DESs exhibit excellent extraction performance towards Cr (VI). At the 1:1 M ratio of DES to Cr (VI), the extraction capacity is as high as 66.7 mg g−1, the extraction efficiency is greater than 90% for ultra-trace Cr (VI) (0.51 μg L−1), and the preconcentration factor is up to 700. When the concentration of coexisting metal ions (Cd2+, Cu2+) and organic compounds ((C 6 H 10 O 5) n , C 6 H 12 O 6 ·H 2 O) is 2000 times that of Cr (VI), the extraction efficiency is still above 90%. Compared with ionic liquid extractants, the preparation process of DES is very simple, the atomic utilization rate is 100%, and no waste is produced. These hydrophobic DESs have been used to separate and enrich Cr (VI) from actual water samples with satisfactory recoveries. The possible extraction mechanism is investigated by FT-IR and 1H NMR. Image 1 • Five kinds of novel hydrophobic deep eutectic solvents (DES) are designed and prepared for the first time. • The preparation process is simple, cheap and does not produce any waste, and the DESs themselves have low toxicity. • The hydrophobic DESs exhibit outstanding extraction performance towards Cr (VI) at both high concentration and ppb level. • Inorganic metal ions and organic compounds do not interfere with the extraction of Cr (VI). [ABSTRACT FROM AUTHOR]