In this paper, the pH-sensitive carbon dots were synthesized by simple one-pot hydrothermal treatment of threonine. The fluorescence of the as-synthesized carbon dots was featured by pH dependence, with the intensity decreasing as pH increases. The carbon dots can be readily internalized into plant pathogenic fungal cells for imaging with dose dependence. Moreover, intracellular pH regulation, a kind of physiological functions of living fungal cells, was visually expressed as the variation of fluorescence intensity of the internalized carbon dots. A transient reduction of the intracellular pH tightly regulated by living fungal cells under basic external condition can be presented as a gradual increase in fluorescence intensity of the carbon dots. On the contrary, the fluorescence of the carbon dots distributed in apple tissue infected by the fungal cells was soon quenched by the basic buffer because there was no intracellular pH regulation in the dead cells. 相似文献
The calcium cobaltite (CCO) cathodes are post-treated by dipping in the hydrogen peroxide (H2O2). The electrochemical properties are investigated by the electrochemical impedance spectra (EIS) and current-voltage test in the symmetrical cell and single cell, respectively. The phase structure and morphology of the cathodes are characterized by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). The experiment results show that the mesopores are created on the surface of the cathode particles and the pore channels of the cathode are cleaned up after leaching with 10 wt % H2O2, resulting in a remarkable decreasing of the area specific resistance (e.g. only 42.5% of that for the untreated cathode at 800 °C). The single cell with treated cathode is about 2 times the peak power density of the cell with untreated cathode, signifying the post-treating method may be promising. 相似文献
The joint optimal operation of cascade reservoir system can greatly improve the utilization of water resources. However, the complex high-dimensional and non-linear features and calculated costs often hinder the refined operation and management of reservoirs. Recently, the local parallel computing has become an effective way to alleviate the "curse of dimensionality". Current local parallel computing has hardware limitations, which is difficult to adapt to large-scale computing. This study proposes a novel parallel dynamic programming algorithm based on Spark (PDPoS) via cloud computing. The simulation experiments are carried out for a comparative analysis of the solution efficiency, influence factors and stability of cloud computing. The results are as follows: (1) The efficiency of the cloud-based PDPoS is related to some factors; the number of CPU cores is the main influencing factor, followed by the operator, and the architecture has the least influence. (2) The runtime variance of cloud computing is 2.03, indicating cloud computing has high stability. (3) Under the same configuration (i.e., CPU and memory), the runtime of cloud computing is 41.5%?~?110.3% longer than that of physical machines. However, cloud computing has rich resources, good scalability, and good portability of online operations, which is an attractive alternative for optimal operation of large-scale reservoir system.