The formal total synthesis of macarpine was accomplished by the construction of a naphthol intermediate in Ishikawa’s synthetic route with two different synthetic routes. The convergent synthetic strategies feature the utilization of Au(I)-catalyzed cycloisomerizations of a 1,5-enyne and alkynyl ketone substrates, which were prepared by Sonogashira coupling reactions.

As the end point of power delivery, a distribution system is directly connected with the consumers. It has complex structures and various operation modes which make the reliability even more important. However, the traditional FMEA cannot be applied to the complex distribution system which contains ring networks. Taking the capacity constraint of distribution system into consideration, this paper analyzes the reliability of IEEE DRTS system with FMEA based on the minimum cut set.

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Addressing problems of larger volume of harmonic gear in the conventional design, in this paper, a mathematical model of optimization with hybrid discrete variables is proposed by taking the modulus of harmonic gear transmission parameters m , the length of flexspline L , wall thickness  and tooth width of flexspline b as design variables, and the sum of volume of circular spline and flexspline as an objective function to be minimized. During the procedure of optimization, the basic idea of the hybrid genetic algorithm is constructed, and the basic procedure of the hybrid genetic algorithm is compiled. The hybrid genetic algorithm used in the parameter optimization of harmonic gear drive is testified to be effective, and optimization results can meet the design standard. Therefore, the proposed method will be of the significant guiding value to engineering practices.