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An efficient method of synthesizing 2-trifluoromethylindoles from indoles with easy-to-handle, cheap and low-toxic CF 3 SO 2 Na under metal-free conditions is described, which selectively introduces trifluoromethyl to indoles on the C2 position. The desired product can be obtained in 0.7 g yield. A radical intermediate may be involved in this transformation., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

In this work, NiFe 2 O 4 nanoparticles were successfully supported on cotton-based carbon fibers through a flexible two-step approach consisting of calcination of cotton in a N 2 atmosphere and subsequent hydrothermal reaction. The incorporation of the NiFe 2 O 4 nanoparticles into cotton-based carbon fibers resulted in better impedance matching, leading to better microwave absorption performance than cotton-based carbon fibers and NiFe 2 O 4 nanoparticles. For NiFe 2 O 4 /carbon fibers, reflection loss (RL) values less than -10 dB were obtained in the frequency range of 11.5-18 GHz with 2.4 mm thickness, which covered the entire Ku-band (from 12 to 18 GHz). Meanwhile, when the matching thickness was 3.2 mm, the RL values less than -10 dB were in the range of 8.0-12.7 GHz, which covered the entire X-band (from 8 to 12 GHz). This excellent and interesting microwave absorption performance can satisfy multiple applications. Owing to the characteristics of a cost-effective synthetic route, low density and excellent microwave absorption, the NiFe 2 O 4 /carbon fibers have a promising future in X-band and Ku-band absorption., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

NO X is a major atmospheric pollutant that is emanated by motor vehicles, thermal power plants, and industrial boilers. Therefore, the removal of NO X is a research hotspot in the exhaust gas treatment field. Numerous methods have been used to eliminate NO X : the selective catalytic reduction of NO X using C 3 H 6 as the reducing agent (C 3 H 6 -SCR) is an effective method to remove NO X . The key issue in NO X removal in C 3 H 6 -SCR is to obtain catalysts with low-temperature activity and wide operating temperatures. Till date, different supported wide-temperature-active molecular sieve catalysts have been prepared and used in C 3 H 6 -SCR reactions. Studies have shown that the catalytic performance of supported catalysts is related not only to the active component but also to the structural and textural parameters of the molecular sieve supports. This review summarizes the structural and textural characteristics, catalytic properties, and catalytic mechanism of molecular sieve catalysts with different pore structures for C 3 H 6 -SCR reactions. The design strategies of supported molecular sieve catalysts are suggested. The goal of this review is to highlight (1) the structural and textural characteristics and low-temperature catalytic performance of different supported molecular sieve catalysts; (2) the relationship between wide-temperature window and loaded active components, as well as carriers of the supported molecular sieve catalysts; and (3) design strategies and development prospects of supported molecular sieve catalysts with low-temperature activity and wide-temperature operating range for C 3 H 6 -SCR reactions., Competing Interests: Authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

Ni-Co-Al 2 O 3 composite coatings were prepared by pulsed electrodeposition and electrophoresis-electrodeposition on aluminum alloy. The content of Al 2 O 3 particles of the Ni-Co-Al 2 O 3 composite coating prepared by electrophoresis-electrodeposition was significantly higher than the composite coating prepared by pulsed electrodeposition. The composite coating prepared by electrophoresis-electrodeposition exhibited a better anti-wear performance than that prepared by pulsed electrodeposition. The morphology, composition and microstructure of the composite coatings were determined by means of X-ray diffractometer (XRD) and scanning electron microscopy (SEM). The hardness and friction properties of the samples were tested on the microhardness tester and the friction and wear loss tester respectively., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)