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Comprehensive Summary: In this paper, we have developed a decarboxylative amination of carboxylic acids with nitroarenes for the synthesis of secondary amines. The protocol is performed at mild conditions without the use of noble metals as catalysts. A wide range of structurally diverse secondary amines could be obtained in good yields (up to 94%) with good functional group tolerance. This transformation shows good to excellent selectivity, avoiding the generation of over alkylated byproducts. [ABSTRACT FROM AUTHOR]

In recent years, the activation of unactivated alkyl chlorides through light-induced processes has emerged as a promising field in radical chemistry, and has led to new transformations in organic synthesis. Direct utilization of alkyl chlorides as C(sp3)-hybridized electrophiles enables the facile construction of carbon–carbon and carbon–heteroatom bonds. Furthermore, recent studies in medicinal chemistry indicate that their presence is associated with high levels of success in clinical trials. This review summarizes the recent advances in the photoinduced activation of unactivated alkyl chlorides and discusses the mechanistic aspects underlying these reactions. We anticipate that this review will serve as a valuable resource for researchers in the field of unactivated chemical bond functionalization, and inspire considerable developments in organic chemistry, drug synthesis, materials science and other related disciplines. [ABSTRACT FROM AUTHOR]

The alkyne unit is a versatile building block in organic synthesis and the development of selective multifunctionalization of alkynes is an important object of research in this field. Herein, we report an interesting gold-catalyzed, four-component reaction that achieves the oxo-arylfluorination or oxo-arylalkenylation of internal aromatic or aliphatic alkynes, efficiently breaking a carbon-carbon triple bond and forming four new chemical bonds. The reaction divergence can be controlled by site-directing functional groups in the alkynes; the presence of a phosphonate unit favors the oxo-arylfluorination, while the carboxylate motif benefits oxo-arylalkenylation. This reaction is enabled by an Au(I)/Au(III) redox coupling process using Selectfluor as both an oxidant and a fluorinating reagent. A wide range of structurally diverse α,α-disubstituted ketones, and tri- or tetra-substituted unsaturated ketones have been prepared in synthetically valuable yields and with excellent chemo-, regio- and stereoselectivity. The gram-scale preparation and late-stage application of complex alkynes have further enhanced their synthetic value. The development of selective multifunctionalization of alkynes is essential for organic synthesis with alkyne units as building blocks. Here the authors report a gold-catalyzed, four-component reaction that achieves the oxo-arylfluorination or oxo-arylalkenylation of internal aromatic or aliphatic alkynes [ABSTRACT FROM AUTHOR]

The paper introduced magnetic flux leakage testing principle of wire rope flaw detector, and used finite element analysis method to analyze impact factors of detection results of wire rope flaw detector based on flux leakage testing principle, the impact factors include material of sensor parts, rope lift-off distance and number of broken wires. The analysis results show that the factors of lift-off distance and the number of broken wires have large impact on detection results of wire rope flaw detector, and the factors of angle and depth of broken wires has little impact on detection results of wire rope flaw detector.

For problems of exiting flame sensors based on infrared detection principle such as short detection distance, long response time and so on, a mine-used flame sensor was developed based on ultraviolet light detection principle. Mathematical model of signal modulation circuit of ultraviolet phototube was established through experiments for calculating circuit parameters to improve response speed of the ultraviolet phototube. Power source and signal transmission circuit were designed with electro magnetic compatibility, so as to improve anti-interference ability of the sensor. The test result shows that the sensor has fast response speed, strong anti-interference ability and good stability and reliability.