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Soil microorganisms directly participate in phosphorus (P) cycle, which in turn affects crop yield and quality. However, how biological and chemical parameters respond to mineral P fertilizer application rates in rhizosphere soil remains unclear. Here, a pot experiment was conducted to investigate the effects of different mineral P fertilizer application rates (0, 60, 120, and 300 kg P2O5 ha−1) on soil chemical properties and bacterial community in maize rhizosphere in a Mollisol. With increasing P fertilizer rates, soil organic carbon concentration decreased, while soil Olsen P and inorganic P and organic P (Po) fractions concentrations increased. High-throughput 16S rRNA gene sequencing showed that the relative abundances of some beneficial bacteria (Anaerolinea, Anaeromyxobacter, Kaistia and Rhodobacter) significantly increased with reduced P fertilizer rates, and meanwhile those of other beneficial bacteria (Mesorhizobium, Microvirga, Rhizobacter and Skermanella) significantly decreased under high P fertilizer rates. Redundancy analysis (RDA) showed that labile Po was the main driver of the differences in bacterial community structure. Bacterial community diversity and composition significantly and indirectly affected maize yield via octacalcium-bound P, occluded Fe/Al-bound P, labile Po, and moderately labile Po. The results suggested that reducing P fertilizer rates can promote beneficial bacterial growth and increase bacterial community diversity.

The thin films of Ti-Si-C-O oxides are fabricated via direct-current magnetron co-sputtering using a Ti3SiC2 target with oxygen (O2). The X-ray photoelectron spectroscopy is used to verified the composition of the Ti-Si-C-O thin films. A memristor is designed as the structure of Pt/TSCO/ITO/glass, and the I-V curves as well as the switching behaviors are studied for the first time. The results indicated that there appear typical pinched hysteresis I-V loops and continuous resistance changes under positive and negative sweeping bias, and that the device conductance can be modulated by consecutive potentiating and depressing programming. The carrier transport mechanism of the device is also investigated and it is found that the Ohmic connection is the leading factor in the linear low electric field region while Schottky emission in the non-liner high electric field region.

In this paper, a multi-channel digital Stretching structure applied to image multi-ships simultaneously is proposed and which is very important for the ISAR to be used in ocean environment with intensive ships. A base band width expression of ship echoes which stands for the maximum length in radial range dimension occupied by the target being imaged is deduced. Based on the fact that ISAR emission signal band width is much wider than the base band width of the target echoes, a fast multi-phase filtering algorithm which leads to a sharply reduction of the computation load in range information processing is introduced and a matrix method of the algorithm is presented. Finally, a formula for estimating the computation load in terms of the radio of radar signal bandwidth to target's base band width is given, and the correctness of the equation is verified by an example from an actual ISAR system.