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Cu catalysts with different compositions and different Cu and promoter contents were prepared by precipitation‐gel method and studied for the selective hydrogenation of syngas or biomass‐based diethyl malonate (DEM) to valuable 1,3‐propanediol (1,3‐PDO). The Ga‐promoted 70Cu6Ga/SiO2 catalyst was found to exhibit the highest catalytic performance, achieving 100 % DEM conversion and 76.6 % 1,3‐PDO selectivity under reaction conditions of 160 °C and 8 MPa H2. The 70Cu6Ga/SiO2 bimetallic catalyst also presented obviously better stability than that of the monometallic 70Cu/SiO2 catalyst in a continuous flow reactor over 180 h time‐on stream. Characterization results showed that the incorporation of Ga increased the interaction between Cu and Ga species, hindered the full reduction of Cu2+ species, and thus increased the proportion of Cu+ and the number of Lewis acidic sites on the catalyst surface. The synergistic effect between Cu0 and Cu+ enhanced the adsorption and activation of ester carbonyl groups and their subsequent hydrogenation, eventually contributed to the outstanding performances of the CuGa/SiO2 bimetallic catalysts. [ABSTRACT FROM AUTHOR]

The scientific analysis of the slalom training process can significantly improve the performance of athletes. In this paper, the P matrix is defined by extracting the multi-joint space coordinate trajectories of the athletes in the video to analyze the slalom training pattern. The principal component analysis was used to extract the main eigenvalues and eigenvectors of the P matrix, which were defined as the main eigenbehaviors of slalom skiing, and six main eigenbehaviors were used to achieve a similarity of 96% between the reconstructed skiing sequence and the original sequence. Similarly, the group characteristic S matrix is constructed by using the individual eigenbehaviors, and the eigenvectors of the matrix are used to define the characteristic behavior of the group to classify the hierarchical group and determine the group to which the individual belongs. Results show that this method can better identify the movement pattern of the human body's multi-joint space trajectory in indoor or outdoor slalom skiing, and provide scientific guidance for skiing training, so that athletes can achieve better training effectiveness. [ABSTRACT FROM AUTHOR]

A new method for determining the orientation of chemical shift tensors in polycrystalline solids with site resolution is presented and its application to the determination of the C alpha chemical shift tensor orientation in a model peptide with beta-sheet torsion angles is demonstrated. The C alpha CSA tensor orientation may be useful as an additional tool for protein structure refinement, especially when the CSA magnitudes give ambiguous information on secondary structure.

The amplitude and geometry of segmental motions in bimolecular and polymeric solids is investigated by the use of Lee-Goldburg cross-polarization (LG-CP) NMR under fast magic-angle spinning. The LG-CP evolution yields simple and well resolved splitting in the frequency domain, whose line shape could be analyzed to extract semiquantitative information on the geometry of motion.