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Effects of different concentrations of biogas slurry (BS) were evaluated relative to vegetable cultivation. Five concentration levels of BS were used as organic fertilizer to grow Chinese cabbages (CA) by drip irrigation to study the effect of BS on the yield and quality. Each level was replicated three times and BS was used seven times. Results showed that the average plant height, fresh weight, dry weight, and soluble sugars and protein contents of Chinese cabbage under the T1 (BS 25%) treatment were optimal. Among them, dry weight per plant (3.53g), soluble sugar content (0.41%), and soluble protein content (0.0039%) were 1.74 times, 1.41 times, and 1.14 times more than under the CK treatment, respectively. In addition, the application of biogas slurry improved the physical and chemical properties of soil. Soil total nitrogen (TN) and available phosphorus (AP) content increased after the use of biogas slurry, and the soil total nitrogen and available phosphorus content increased with the increase in the concentration of the applied biogas slurry. The available potassium (AK) content of soil fluctuated with the concentration of biogas slurry. In addition, biogas slurry can properly improve soil pH. In conclusion, BS 25% was the best for the growth of CA and its quality, which provided scientific basis for biogas slurry as fertilizer. [ABSTRACT FROM AUTHOR]

The Luoxiao Mountains play an important role in maintaining and supplementing the fish diversity of the Yangtze River Basin, which is also a biodiversity hotspot in China. However, fish biodiversity has declined rapidly in this area as the result of human activities and the consequent environmental changes. Beta diversity was a key concept for understanding the ecosystem function and biodiversity conservation. Beta diversity patterns are evaluated and important information provided for protection and management of fish biodiversity in the Luoxiao Mountains. The results showed that the spatial turnover component was the main contributor to beta diversity of Hemiramphidae, Amblycipitidae, Catostomidae, Clariidae, Balitoridae and Percichthyidae in the Luoxiao Mountains, which indicated that a number of protected areas would be necessary to conserve fish biodiversity and that these families would need conservation measures. Most protected areas are currently limited to some regions; therefore, in order to protect fish diversity, conservation efforts must target an increase in the number of protected areas which should be spread across each of the regions. [ABSTRACT FROM AUTHOR]

In organic resistive memory device field, alternating current (AC) has seldom been studied systematically. In the present work, square wave voltage pulses are considered to obtain memory switching to the ON state with voltage amplitude lower than the threshold voltage of the device, even with less time. The ON states induced by such AC depend on both frequency and amplitude. A possible mechanism related to filamentary formation was proposed to explain the AC induced effect. [ABSTRACT FROM AUTHOR]

Optoelectronic behavior in materials such as organic/inorganic hybrid perovskites depend on a complex interplay between fast (electronic) and slower (ionic) processes. These processes are thought to be influenced by structural inhomogeneities (e.g. interfaces and grain boundaries) bringing forward the necessity for development of techniques capable of correlating nanostructure and photo-transport behavior. While Kelvin probe force microscopy (KPFM) is ideally suited to map surface potentials on relevant length scales, it lacks sufficient temporal resolution to extract the meaningful system dynamics. Here, we develop a time resolved surface photovoltage (SPV) measurement based on full information capture of the photodetector stream during open loop KPFM operation. G-Mode, or G-KPFM allows quantification of SPV with microsecond temporal and nanoscale spatial resolution. Using this technique, we observe concurrent spatial and fast temporal variations in the SPV generated across a methylammonium lead bromide (MAPbBr3) thin film, a possible indicator relating microstructure with heterogenous photo-transport behavior. We further demonstrate the advantage of adopting big data analytics including unsupervised clustering methods to quickly discern spatial variability in the information rich SPV dataset. Beyond G-KPFM, such clustering methods will be useful for interpretation of the multidimensional datasets arising from the growing number of time resolved KPFM approaches now available. [ABSTRACT FROM AUTHOR]

An ultra-thin molybdenum(VI) oxide (MoO3) modification layer can significantly improve hole injection from an electrode even though the MoO3 layer does not contact the electrode. We find that as the thickness of the organic layer between MoO3 and the electrode increases, the hole injection first increases and it then decreases. The optimum thickness of 5 nm corresponds to the best current improvement 70%, higher than that in the device where MoO3 directly contacts the Al electrode. According to the 4,4-bis[N-(1-naphthyl)-N-phenyl-amino] biphenyl (NPB)/MoO3 interface charge transfer mechanism and the present experimental results, we propose a mechanism that mobile carriers generated at the interface and accumulated inside the device change the distribution of electric field inside the device, resulting in an increase of the probability of hole tunneling through the injection barrier from the electrode, which also explains the phenomenon of hole injection enhanced by MoO3/NPB/Al composite anode. Based on this mechanism, different organic materials other than NPB were applied to form the composite electrode with MoO3. Similar current enhancement effects are also observed. [ABSTRACT FROM AUTHOR]

To identify the effect of drift/diffusion current on the fill factor (FF) of organic solar cells, the correlation between FF and drift/diffusion current is studied with thickness/type of donor material, temperature and doping as the experimental parameters. Experimental results show that FF is positively related to the diffusion current. Because of the suppression of carrier diffusion, generated carriers will accumulate at the donor–acceptor interface, resulting in carrier recombination. [ABSTRACT FROM AUTHOR]