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Research on the chemoselective metal‐catalyzed hydrogenation of conjugated π‐systems has mostly been focussed on enones. Herein, we communicate the understudied asymmetric hydrogenation of enimines catalyzed by N,P‐iridium complexes and chemoselective toward the alkene. A number of enoxime ethers underwent hydrogenation smoothly to yield the desired products in high yield and stereopurity (up to 99 % yield, up to 99 % ee). No hydrogenation of the C=N π‐bond was observed under the applied reaction conditions (20 bar H2, rt, DCM). It was demonstrated that the chiral oxime ether could be hydrolyzed into the ketone with complete preservation of the installed stereogenity at the α‐carbon. At last, a binding mode of the substrate to the active iridium catalyst and the consequence for the stereoselective outcome was proposed. [ABSTRACT FROM AUTHOR]

Human activities in daily life and industrial production generate a significant volume of substandard water with high salt content, organic compounds, and other pollutants, often exhibiting a neutral pH. Electrochemical oxidation is a widely applied technique for the purification of water sources. By integrating electrochemical oxidation reactions with electrolytic hydrogen evolution reactions, the potential arises to enhance energy utilization efficiency and reduce cost implications. This study describes the advantages and challenges of neutral aqueous chlorine solutions as electrolytes for hydrogen production from electrolyzed water. The cathodic and possibly anodic reactions in the electrolysis of neutral chlorinated electrolytes are also investigated. Finally, we present the progress of research on cathode and anode catalysts used in electrolyzing neutral chlorine-containing electrolytes. The aim is to inspire the research of industrialized low-cost and high-yield integrated hydrogen production systems. [Display omitted] • Concluded the challenges of electrolysis of neutral chlorine-containing solutions. • Low-energy anode reaction coupled with hydrogen evolution reaction can reduce lower. • Concludes the design principles of cathode and anode catalysts for water splitting. [ABSTRACT FROM AUTHOR]

This study reports magnetic graphene oxide composite microspheres (MGO) were firstly synthesized via one step miniemulsion polymerization. α-FeOOH rods were then loaded onto MGO via a facile hydrothermal method to prepare α-FeOOH@MGO, which was served as the photocatalyst for the Fenton reaction. Subsequently, the properties of the resulting α-FeOOH@MGO were characterized by FT-IR, XRD, SEM, VSM and UV-vis DRS analysis methods. The influence of various parameters was investigated, such as dye type, dye concentration, H2O2 dosage, catalysts dosage and pH of MO solution during heterogeneous photo-Fenton processes. Under visible light irradiation, the degradation rate of MO, MB and CR could reach 99.96%, 98.47% and 99.97% in 40 min, respectively. Six cycle experiments confirmed that the α-FeOOH@MGO possessed a satisfied stability and recycling ability. In addition, the photocatalytic reaction mechanism was also revealed by the Mott-Schottky plot, band structure and trapping experiments of active species. [ABSTRACT FROM AUTHOR]

A silver-promoted radical mechanism is proposed for this reaction. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide (H2S) is widely found in oil and natural gas wells and industrial wastewater tanks. Owing to its high toxicity, the monitoring and detection of H2S in the air is essential. However, recent techniques for the quantitative detection of H2S gas suffer from limitations such as high cost, complicated operation, and insufficient sensitivity, preventing their practical application in industry. Thus, we have developed a portable test paper for real-time and inexpensive monitoring of H2S gas by color changes. The test paper had a significantly low H2S detection limit of 200 ppb, which is considered safe for humans. Moreover, the color of the test paper did not change noticeably when exposed to CO2, N2, O2, and air environments, indicating that the test paper is selective for H2S gas and can be stored for a long time. In addition, we fitted a color difference linear model between the color difference values (ΔE) and the concentrations of H2S gas. The establishment of the linear model substantiates that the test paper can provide accurate intensity information when detecting H2S gas leakage. [ABSTRACT FROM AUTHOR]

The scalable hydrogenation of vinylic, allylic, and homoallylic sulfones is investigated with the conversion of the E-isomers being faster than the one of Z-isomers while delivering opposite enantiomers. [ABSTRACT FROM AUTHOR]

Biochar was modified by an acylation reaction using EDTA. Then, a novel biochar-based porous composite was successfully prepared using modified biochar as a base to remove Cu(II) in wastewater. In addition, functional groups, morphologies and the specific surface areas of EDTA-BIOC hydrogel were characterized by FT-IR, SEM, and BET, respectively. Various factors affecting the adsorption of Cu(II) on EDTA-BIOC hydrogel were investigated, such as pH, temperature, contact time, salinity, and initial concentration of Cu(II). Addition of EDTA greatly improved the adsorption capacity for Cu(II), and the maximum adsorption capacity of EDTA-BIOC hydrogel for Cu(II) was 93.9 mg g−1 at 318 K, which was higher than for biochar, gel-0 and EDTA-BIOC/SiO2 hydrogel. Cu(II) adsorption on EDTA-BIOC hydrogel was shown to fit well with the pseudo-second-order kinetic model and Langmuir isotherm. The adsorption mechanisms of Cu(II) by the hydrogel are systematically discussed, including physical adsorption, electrostatic attraction, cation exchange and complexation. Furthermore, EDTA-BIOC hydrogel could maintain a high adsorption capacity after five adsorption–desorption processes, which provided the possibility for recycling the EDTA-BIOC hydrogel multiple times. Finally, the adsorption capacity of EDTA-BIOC hydrogel for Cu(II) was studied in various water samples. The experimental results showed that EDTA-BIOC hydrogel exhibited great potential for treating different wastewaters containing Cu(II). [ABSTRACT FROM AUTHOR]

[Display omitted] • Wastewater sediments were used to synthesize large surface area GNS. • The metal elements (Fe, Mn, Ca) in the catalyst greatly enhanced the GNS yield. • The maximum adsorption capacity of methylene blue by GNS was 1092.1 mg/g. • Decolorization rates (>98.5 %) were achieved for the simulated textile wastewater. Development of high performance adsorbents through the recovery of waste resources for wastewater treatment is a sustainable strategy for environment protection. Here, graphene nanosheet (GNS) adsorbent with extremely high surface area of 1149.7 m2/g was synthesized by one-step chemical vapor deposition using catalysts derived from wastewater for the first time. The obtained catalyst was mainly composed of MgO and a small amount of Fe 2 O 3 , MnO 2 and CaO, and the presence of these metal oxides in the catalyst improved the catalytical activity of MgO, leading to the enhanced yield of GNS. The GNS yield was 144 % higher than that of GNS synthesized on commercial MgO. The possible growth mechanism of GNS was discussed. The adsorption of methylene blue (MB) on GNS was then systematically investigated, and GNS demonstrated excellent adsorption capacity and extremely fast adsorption rate for MB at a wide pH range (2–12) and different temperatures (293–313 K). GNS has achieved a high removal efficiency of ∼ 99.0 % in 20 min, and its maximum adsorption capacity was 1092.1 mg/g. The adsorption kinetic and isotherms by GNS were also studied. The adsorption results were closely fitted by Langmuir isotherm model and pseudo-second-order kinetic model. The adsorption of MB on GNS involved multiple adsorption mechanisms, including electrostatic interactions, hydrogen bonding, and π-π stacking interaction. Based on the regeneration experiment, the GNS demonstrated good reusability, retaining a removal efficiency of 95 % after 5 cycles. Finally, high decolorization rates (98.5–99.9 %) were obtained using GNS in the treatment of simulated textile wastewater. This study provided a sustainable method for wastewater treatment by low cost and efficient adsorbents benefitted from the effective utilization of wastewater resources. [ABSTRACT FROM AUTHOR]

Titanium alloys are widely used in many domains due to their excellent high specific strength and corrosion resistance. Stress plays a very important role in the application of titanium alloys. In order to shed light on the titanium alloys corrosion mechanisms under varying stress conditions, this paper first reviewed the impact of elastic and plastic stress on the corrosion behavior of titanium alloys. And then reviewed the influence of stress caused by surface treatment, such as laser welding, laser strengthening, and ultrasonic surface treatment, on corrosion behavior. Finally reviewed the effect of factors, including temperature, pH value, oxygen content and alloying elements, on titanium alloys corrosion behavior with stress. Hope this work demonstrated clearly that the corrosion mechanism of titanium alloy with various stress, and offering valuable support for future research and applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • The oxidation mechanism and the influencing factors of EOPs are systematically presented. • The advantages and limitations of commonly used anode materials and their evaluation criteria and systems are reviewed. • The key challenges of EOPs in theoretical research and practical application are analyzed. • Perspective and suggestions for the future development of EOPs are proposed. Compared with conventional wastewater treatment processes, electrochemical oxidation processes (EOPs) can remove hazardous substances from wastewater more efficiently and without pollution. With the rapid development of green power technology, there are more development prospects for EOPs in wastewater treatment. In recent years, research related to EOPs in the field of wastewater treatment has flourished, numerous researchers have reviewed the last advances. However, the key challenges and future directions of EOPs in the context of carbon neutrality are still under-analyzed. In this review, we first summarize the oxidation mechanism and various control factors of EOPs. Then, we discuss the current development status of current and emerging electrode materials, and summarize their commonly used evaluation criteria and systems. Finally, based on the above review, we analyze the key challenges faced by EOPs in theoretical research and practical applications, and propose potential directions for the development of EOPs in wastewater treatment to meet the growing demand for carbon neutrality. We believe that this review will offer crucial guidance and reference to enhance the application and dissemination of EOPs in organic wastewater treatment. [ABSTRACT FROM AUTHOR]

• The h-BN was co-modified by mechanical exfoliation and chemical modification. • The PEI-BNNS/EP exhibits a superior and long-term anticorrosion performance. • The PEI enhances the crosslink density of EP and reduces the defects of coating. The hexagonal boron nitride (h-BN) has extensive promise for metal corrosion protection due to its good impermeability to gas and liquid. However, the practical application of h-BN in polymer composites is limited by surface incompatibility. Herein, we prepared a homogeneous dispersion of h-BN in water-borne epoxy (EP) matrix by mechanical exfoliation and chemical modification, in which the h-BN powder was ultrasonic to obtain partially hydroxylated BN and the products were modified with water-soluble branched poly-ethyleneimine (PEI) via Lewis acid-base interaction. The electrochemical test (EIS and potentiodynamic polarization) and salt spray test in NaCl solution were used to analyze the corrosion resistance performance of composite coatings. The results show that PEI-BNNS/EP coating has superior and long-term anticorrosion performance for P110 mild steel. The impedance modulus (Z f = 0.01 Hz) of PEI-BNNS/EP still has 6.63 × 107 Ω cm2 after 70 days immersion in the 3.5 wt. % NaCl solution. The PEI has an important role for enhancing the anticorrosion property of PEI-BNNS/EP coating, which increases the dispersibility and compatibility of h-BN in EP and the crosslink density of epoxy resin. Our study gives a strategy for the preparation of easy dispersion h-BN nanosheets in large quantities, thus broadening its practical application in the polymer material field. [ABSTRACT FROM AUTHOR]

Highlights • Inner reinforcement and outer modification have been combined for the first time to enhance the EP/CNFs coating. • The barrier and mechanical performances of EP/MoS 2 -CNFs have been improved compared with previous EP/CNFs coating. • The MoS 2 -CNFs composite was prepared via electrospun, which is a simple and effective method. • The relationship between mechanical property and corrosion resistance of coating has been discussed for the first. Abstract To enhance the anticorrosive and mechanical performances of carbon nanofibers (CNFs) in epoxy (EP) coatings, molybdenum disulfide (MoS 2) and γ- (2, 3-epoxypropoxy) propytrimethoxysilane (KH560) have been combined for inner reinforcement and outer surface modification based on CNFs. The electrochemical impedance spectroscopy, tensile testing and microhardness testing demonstrated that MoS 2 -CNFs (0.8%) composite can prominently enhance the anticorrosive and mechanical performance of the EP coating. Furthermore, the impedance of EP/MoS 2 -CNFs (0.8%) was higher than that of the pure EP and other composite coatings, and the Young's modulus (EY) and tensile strength (σs) of EP/MoS 2 -CNFs (0.8%) were increased by 65.4% and 56.6%, respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • Molecular dynamics stimulation was first applied to explains the process of wet granulation. • Wet granulation of the sticky powder-like herbal extracts of TCM were explored. • Provides unique insights into the competition mechanism detailed of binder liquid and solid powder. • Result of stimulation is consentient with the experimental one. In high shear wet granulation (HSWG), the interaction mechanism between binder and powder with different sugar content is still unclear. Herein, the law and mechanism of the interaction between binder and powder were studied on the molecular level by combining experiment analysis through the Kriging model and molecular dynamics (MD) simulation. For the sticky powder with high sugar content, the ethanol in the binder played a pivotal role in dispersing water into powders, and the amount of water determined the growth of granules. In the saturating stage, the reduction of sugar content facilitates the penetration of ethanol molecules. The concentration of ethanol determines whether the mixture is blended uniformly in the merging stage. The simulation results are consistent with the actual situation and explain the competition mechanism of interaction with binder and powder. Therefore, this research offers an efficient strategy for the in-depth understanding of the HSWG process where the powder is sticky, as well as providing guidelines for the practical application of preparation for Traditional Chinese Medicine (TCM) granules. [ABSTRACT FROM AUTHOR]

Recently, Pickering emulsions stabilized by photocatalytic nanomaterials have become a hotspot in the field of catalysis due to their high interfacial activity. However, since most photocatalytic nanomaterials are extremely hydrophilic, using them as stabilizers is unconvenient for Pickering emulsions construction. Herein, a novel magnetic Janus nanosheets (JMPSN/α-FeOOH) with Janus SiO 2 nanosheets as the carrier and iron oxyhydroxide (α-FeOOH) as the catalyst species, respectively, was successfully fabricated through a simple synthetic strategy, which could act as an environmental-friendly Pickering emulsion emulsifier and catalyst simultaneously. We demonstrated that JMPSN/α-FeOOH exhibited good emulsifying properties of various oil phases. Morever, JMPSN/α-FeOOH in the formed Pickering emulsion-based photocatalytic system displayed significantly enhanced photocatalytic efficiency in degradation of dyes as compared to traditional non-emulsified systems while maintaining the stability of Pickering emulsion under constant irradiation. JMPSN/α-FeOOH could also quickly respond to external magnetic fields so as to achieve rapid recovery of catalyst, and catalyst still showed high catalytic activity after many catalytic cycles. Finally, a convenient and promising synthesis strategy for preparing Janus catalyst with low toxicity was proposed, which provided a guidance on how to effectively use the emulsion system stabilized by Janus catalyst to improve the degradation efficiency of various pollutants. [Display omitted] • An oil-in-water Pickering emulsion was stabilized by JMPSN/α-FeOOH without the use of any surfactants. • Pickering emulsion showed excellent photoefficiency and stability for dyes degradation. • JMPSN/α-FeOOH could quickly respond to external magnetic signals. • JMPSN/α-FeOOH still showed high catalytic activity after many catalytic cycles. [ABSTRACT FROM AUTHOR]

[Display omitted] • Uniform nanoporous is prepared on high-entropy amorphous alloy by controllable corrosion. • The electrode shows superior HER catalytic performance and corrosion resistance in hot H 2 SO 4. • Provide a strategy for in situ construction and repair of the catalytic interface. Producing high-purity hydrogen from water electrolysis using intermittent renewable electricity is fascinating and challenging. Noble metal-based high-entropy alloy with near-equimolar mixed elements have unique properties including cocktail effect, high entropy effect and lattice distortion effect, which are beneficial to improve catalytic performance and reduce the amount of noble metal. Taking advantages of excellent mechanical properties, high thermal stability and corrosion resistance, as well as chemical uniformity and tunability, equiatomic high-entropy metallic glass PdPtCuNiP was employed to construct nanosponge-like architecture with uniform nanopores via a precise strategy of potentiostatic electrochemical dealloying, which presented superior hydrogen evolution reaction (HER) electrocatalytic performance in hot dilute H 2 SO 4. The Tafel slope is 34.2 mV dec−1 and the overpotential corresponding to 10 mA cm−2 is 35.4 mV, outperforming commercial Pt/C catalyst and most currently available electrocatalysts. Furthermore, even electrocatalytic performance of nanoporous PdPtCuNiP is degraded tinily by hot dilute H 2 SO 4 accordng to power-off or low-voltage operation of water-electrolysis system, it can be directly refreshed by in-situ potentiostatic polarization in the electrolyzer. We believe the strategy of in-situ construction and repair of nanostructured electrocatalytic surface on high-entropy alloy in this study will call for more endeavors to realize the practicality of hydrogen production in harsh acidic electrolyte. [ABSTRACT FROM AUTHOR]

Hexagonal boron nitride (h-BN) has great promise for metal corrosion due to its good impermeability to gas and liquid. However, it is difficult for h-BN to disperse in water-borne epoxy (WBE) matrix owing to its nature hydrophobicity. In this work, h-BN was non-covalently modified by graphene oxide (GO) to enhance the compatibility of h-BN for WBE. And the GO/h-BN composite was characterized by transmittance electron microscopy (TEM), Raman spectroscopy, UV–vis absorbance spectroscopy and X-ray photoelectron spectroscopy (XPS). The corrosion protection and barrier performance of GO/h-BN/WBE were evaluated by electrochemical impedance spectroscopy (EIS) and salt spray test, which indicated that the composite coating with 0.3 wt. % GO/h-BN (1:1 w/w) additive exhibited excellent barrier and corrosion protection properties owing to the synergistic impermeable performance of h-BN and GO. [ABSTRACT FROM AUTHOR]