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The development of eco-friendly electroactive nanomaterials has attracted great attention in recent years. Here, a biogenic piezoelectric and fluorescent nanocomposite was designed and fabricated. Cellulose nanorods (CNRs) were first modified with polyethylenimine (PEI)-functionalized carbon dots (CDs) with dual-band green/yellow photoluminescence (PL). The CD-modified CNRs were incorporated into an electrospun poly-(vinyl alcohol) (PVA) nanofiber with a piezo-phase alignment. CDs with an amino-rich polymeric chain not only enhanced the crystallinity of the CNRs but also mediated flexible linking between the CNRs and PVA matrix, which facilitated a large-scale preferential alignment of the CNRs in the nanofibers. The piezoelectric output voltage of the composite was improved two times through introduction of the CDs. Furthermore, the inhomogeneous distribution of the dual-emissive CDs in the nanofiber endowed the composite film with a unique thickness-dependent fluorescent chromic behavior. An information encryption was also realized owing to the structural-sensitive fluorescence of the composite film, which showed the high potential of the multifunctional nanocomposite in various applications. [ABSTRACT FROM AUTHOR]

Aiming at the shortcomings in current power equipment supplier evaluation, this paper is designed for different types of project comprehensive evaluation models. First of all, starting from the type of project and engineering needs, the indicator system was established in four aspects: qualification ability, process control, operation quality, and service quality. Then, the subjective weight and objective weight of each evaluation index were calculated by the fuzzy analytic hierarchy process (AHP) and factor analysis method. The final weight was obtained by a combination weighting method. The supplier category was determined according to the principle of maximum membership, and the final evaluation was completed. Finally, the evaluation model was verified by the distribution transformer supplier, and the results proved the objective rationality of the evaluation model.

In this paper, based on the traditional LCMV beamformer and sub-array space partial adaptive array, a novel dimensionality reduction method is proposed. Firstly, the large-scale array is divided into several groups of sub-arrays according to a certain rule of sub-array division, and each group of sub-arrays uses the same weight. In the process of weight optimization, each time only a part of the weight vector is updated, the system search obtains the optimal weight through multiple iterations, which avoids the inversion of the full-dimensional correlation matrix. The experimental results show that compared with the traditional method, this method can obtain higher signal to interference and noise ratio and reduce the dimensionality of the inversion matrix in large-scale array beamforming, which reduces the computational complexity and hardware cost to a certain extent.

The new multiple access technology plays a very important role in 5G mobile communication system. In this article, a new non-orthogonal complex space division multiple(CSDM) technique is proposed and combined with traditional multiple input multiple output(MIMO) system to form CSDM-MIMO system. The CSDM-MIMO system can transmit multiple user data on one antenna at the same time and same frequency, which improves the data transmission rate and system capacity. The system special virtual channel is estimated by least squares(LS) algorithm and minimum mean square error(MMSE) algorithm respectively. At the same time, the optimal weight of the system is searched by the bit error rate(BER) fed back by the receiver and artificial fish swarm algorithm(AFSA).

Soil microorganisms and their diversity are important bioindicators of soil carbon and nutrient cycling. Land use type is a major determining factor that influences soil microbial community composition in floodplain ecosystems. However, how the structure and diversity of soil microbial communities respond to specific changes in land use, as well as the main drivers of these changes, are still unclear. This study was conducted in the Yellow River floodplain to examine the effects of land use type on soil microbial communities. Four land use types (shrubland, farmland, grassland and forest) were selected, wherein shrubland served as the baseline. We measured soil microbial structure and diversity using phospholipid fatty acids (PLFAs). Land use type significantly affected total, bacterial and fungal PLFAs, and the gram-positive/negative bacterial PLFAs. Compared with shrubland, peanut farmland had higher total and bacterial PLFAs and forest had higher fungal PLFAs. Soil pH and phosphorus were the predominate drivers of microbial PLFAs, explaining 37% and 26% of the variability, respectively. Soil total nitrogen and nitrate nitrogen were the main factors increasing microbial community diversity. Peanut farmland had the highest soil carbon content, soil carbon stock, total PLFAs and microbial diversity, suggesting that farmland has great potential as a carbon sink. Our findings indicated that peanut farmland in the Yellow River floodplain is critical for maintaining soil microbial communities and soil carbon sequestration. [ABSTRACT FROM AUTHOR]

The floodplain ecosystem plays an important role in the mediation or regulation of regional ecological functions, and is the heart of ecosystem functions based on soil microbial communities. In the present study, we investigate the patterns and assembly processes of soil microbial communities along nine profile depths (up to 280 cm in depth) of three stages of floodplain community succession (channel bar, newly deposited river beach and tender floodplain) and farmland in the floodplain of the lower Yellow River. Generally, the bacterial community in agricultural soil had the highest diversity, whereas the archaeal community in the tender floodplain had the highest diversity. Compared to bacteria, the co‐occurrence network of archaea was more complex and stable and had high connectivity. Our data suggest that the resistance of bacteria and archaea to environmental changes in deep soil was higher when compared to that in surface soil. Furthermore, stochastic and deterministic processes acted concurrently to regulate the assembly of the soil microbial community in the floodplain ecosystems. However, the relative contributions of the stochastic process and deterministic process are different between the bacterial community and the archaeal community. The lowest contribution of the stochastic process in the bacterial community was in the subsoil, whereas in the archaeal community, it was the opposite. For ecological selection, bacterial communities in different soil profiles, in the succession stages and in the farmland, were mainly selected through homogeneous selection, whereas archaeal communities were selected through heterogeneous selection. Compared with the three floodplain succession stages, the microbial communities of agricultural lands were more assembled by deterministic processes. Highlights: Stochastic and deterministic processes act concurrently to regulate the assembly of soil microbial community in the floodplain ecosystems.The assembly of the bacterial community was mainly affected by the homogeneous selection.The archaeal community was mainly affected by the heterogeneous selection.The microbial communities of agricultural lands were more assembled by deterministic processes. [ABSTRACT FROM AUTHOR]