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Abstract Ammonia is not only an important platform chemical for industrial and agricultural use but is also a novel energy‐carrying molecule. The electrochemical reduction method for ambient ammonia synthesis is emerging as a promising strategy for the replacement of the current Haber–Bosch ammonia synthesis method, which consumes a large amount of energy and natural gas (hydrogen resource) while releasing substantial greenhouse gases (eg, carbon dioxide). The challenges in electrochemical ammonia synthesis, also known as nitrogen reduction reaction, primarily include the cleavage of extremely stable N≡N bonds and the competitive hydrogen evolution reaction in routine aqueous media, which significantly leads to a low production rate and Faradaic efficiency. The rational design and engineering of the electrocatalyst/electrolyte interface are crucial to address these challenges. Herein, recent achievements for catalyst/electrolyte interface engineering are reviewed to provide insights into enhancing the production rate and Faradaic efficiency. Perspectives on future research and development of the electrochemical ammonia synthesis from theory to practice will be provided.

Analyzing the feasibility of modifying setting values on the condition of the running line without exiting the protection function is of great importance for 110 kV substations. A system-level test of settings modification is proposed to verify that the values are correctly modified during the process and the protection function is still in effect. A cyber-physical automatic test bed using a real-time digital simulator (RTDS) is developed for relay protection to modify settings online, which distinctly improves work efficiency. Based on actual power grid parameters, a full-process closed-loop RTDS automatic control system is applied for performance testing when setting groups are changed. The experiments are focused on blocking time tests, setting groups switch and coverage tests, DC power supply intermittent tests, unwanted operations in setting value, changing load and protection starting tests, short-circuit fault tests and power system frequency oscillation tests. The results of the trial indicate that the automatic test bed is an effective technology for checking and verifying the reliability of modifying setting values online. In addition, 36 line protection devices from 12 relay protection manufacturers are tested. The reliability of each test item is analyzed and the relay performance is evaluated using a comprehensive method. The test bed provides reliable technical support for the design, engineering, commissioning and substation operation of online setting modification.

A novel procedure is established for the Pd-C catalytic N-debenzylation of benzylamines in the presence of 1,1,2-trichloroethane. The method has proceeded in the synergistic catalytic system and has given the products as crystal amine hydrochlorides in quantitative yields.

A liquid sizing agent containing carbon nanotubes was prepared for carbon fiber reinforced unsaturated polyester composite applications. The formation of chemical bonds among vinyl-functionalized carbon nanotubes, vinyl-functionalized carbon fibers, and unsaturated polyester in the coating was due to the radial polymerization process. Scanning electron microscopy images showed that a thin layer of unsaturated polyester coating containing carbon nanotubes was grafted on the surface of carbon fiber uniformly. Dynamic contact angle measurements, before and after sizing treatment, demonstrated an improvement in the surface energy and wettability that related to the increase of the polarity of sized fiber surface. X-ray photoelectron spectroscopy was used for surface functional group analysis of carbon fibers. Force modulation atomic force microscope (AFM) images indicated that an interface with local stiffness softer than that of carbon fiber and harder than that of matrix was gained. Results of the mechanical property tests showed that interlaminar shear strength increased from 46.7 to 64.5 MPa by 38% without sacrificing base fiber strength, and the impact resistance was increased simultaneously. [ABSTRACT FROM AUTHOR]

This paper explores the durability and mechanical properties of concrete reinforced by basalt fiber, a natural inorganic nonmetallic material with a good prospect of engineering application, under magnesium sulfate corrosion. The concrete blocks with the side length of 100mm were added 0%, 0.05%, 0.1%, 0.2%, 0.3% basalt fiber, immersed in magnesium sulfate solution with a concentration of 5.0%, and observed continuously for 270 days. After that, the test blocks were subjected to the analysis on the variation of water absorption rate, and compared with ordinary concrete through compressive strength test and ion concentration measurement. The research results show that basalt fiber partially improved the compressive strength and deformation capacity of the concrete; in the magnesium sulfate solution, the pores in basalt fiber-reinforced concrete developed slower than those in ordinary concrete; however, excessive dosage of the fiber has a negative impact on concrete durability; the most economic and rational dosage of basalt fiber is around 0.1%. In addition, a dispersion method of powder particle basalt fiber was proposed to overcome the low dispersiveness of the fiber. The research findings lay the basis for the engineering application of basalt fiber. [ABSTRACT FROM AUTHOR]