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Land Use/Cover Change (LUCC) has gradually became an important direction in the research of global changes. LUCC is a complex system, and entropy is a measure of the degree of disorder of a system. According to land use information entropy, this paper analyzes changes in land use from the perspective of the system. Research on the entropy of LUCC structures has a certain “guiding role” for the optimization and adjustment of regional land use structure. Based on the five periods of LUCC data from the year of 1990 to 2010, this paper focuses on analyzing three types of LUCC entropies among counties in China—namely, Shannon, Renyi, and Tsallis entropies. The findings suggest that: (1) Shannon entropy can reflect the volatility of the LUCC, that Renyi and Tsallis entropies also have this function when their parameter has a positive value, and that Renyi and Tsallis entropies can reflect the extreme case of the LUCC when their parameter has a negative value.; (2) The entropy of China’s LUCC is uneven in time and space distributions, and that there is a large trend during 1990–2010, the central region generally has high entropy in space.

Nowadays, AC charging piles are widely used, and with the increasing number of charging piles, the harmonic pollution generated by them becomes more serious and affects the power quality of the grid. Aiming at the problem of harmonic control of the single-phase AC charging pile, it is decided to apply the active filter technology. The single-phase parallel active filter (PAPF) is selected according to the characteristics of the charging pile. The single harmonic detection method is studied based on instantaneous reactive power theory, and a new adaptive low-pass filter with fixed-step size is proposed to improve the performance of harmonic detection by combining the least mean square (LMS) and the least fourth-order moment (LMF) adaptive algorithms. The PAPF control part adopts the composite control strategy of inner and outer loop combined with repetitive control to complete the voltage stabilization control, harmonic tracking, and compensation. Based on MATLAB/SIMULINK, the output waveforms of the low-pass filter link are simulated and analyzed, and the prototype experiment is carried out. The results verify that the algorithm can improve the performance of harmonic detection. Finally, the single-phase PAPF system simulation is established and the harmonic compensation capability of system is analyzed by the Fast Fourier Transform (FFT). The results demonstrate that single-phase PAPF can effectively manage harmonics and the total harmonic distortion (THD) is reduced to less than 5%.

Amino acid is the main transport form of reduced nitrogen in plants. To investigate the uptake and source–sink translocation process of plants to help understand their physiological roles and transport mechanisms, we designed and synthesized three fluorescent-dye-labeled amino acids as tools to visualize amino acid transportation in Arabidopsis thaliana; these amino acids consist of amino acids linked to the fluorophore nitrobenzoxadiazole (NBD) with excellent optical properties. Furthermore, we incubated Arabidopsis thaliana with these NBD fluorescent-dye-labeled amino acids for real-time imaging along with fluorescence enhancement for 24 h. The results showed that Arabidopsis thaliana could absorb them directly from the roots to the leaves. Therefore, our fluorescent-dye-labeled amino acids provide a de novo tool and strategy for visualizing amino acid absorption and transportation in plants.