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The in situ synthesis of ZnO-embedded Zn1−xCdxS/CdS heterostructure nanocrystals was achieved by using a simple surfactant-free hydrothermal route. The morphology and the exposed active site content of Zn1−xCdxS/CdS could be facilely modulated by varying the particle size of ZnS precursors, and the heterostructure with the smallest particle size showed the highest photocatalytic activity of 22.99 mmol h−1 g−1 in Na2S + Na2SO3 solution. Furthermore, the in situ embedding of the ZnO cocatalyst on the Zn1−xCdxS/CdS heterostructure dramatically improved its photocatalytic activity to 84.17 mmol h−1 g−1, which is 765 times higher than that of CdS prepared by a hydrothermal method. More significantly, the ZnO-embedded Zn1−xCdxS/CdS heterostructure gave a considerable H2 production rate even in the absence of hole scavengers, whereas the bare Zn1−xCdxS/CdS exhibited no hydrogen evolution, and it showed very competitive photocatalytic activity in methanol in comparison with that in Na2S + Na2SO3 solution under similar alkaline circumstances. These investigations indicate that the existence of the ZnO cocatalyst in the heterostructure could not only effectively improve the photocatalytic activity by suppressing the recombination of charge carriers and acting as a photocatalytic reaction site, but also make it possible to adopt methanol as the sacrificial reagent for sulfide photocatalysts.

There is a recognized challenge in analyzing traditional Chinese medicine formulas because of their complex chemical compositions. The application of modern analytical techniques such as high-performance liquid chromatography coupled with a tandem mass spectrometry has improved the characterization of various compounds from traditional Chinese medicine formulas significantly. This study aims to conduct a bibliometric analysis to recognize the overall trend of high-performance liquid chromatography coupled with tandem mass spectrometry approaches in the analysis of traditional Chinese medicine formulas, its significance and possible underlying interactions between individual herbs in these formulas. Electronic databases were searched systematically, and the identified studies were collected and analyzed using Microsoft Access 2010, Graph Pad 5.0 software and Ucinet software package. 338 publications between 1997 and 2015 were identified, and analyzed in terms of annual growth and accumulated publications, top journals, forms of traditional Chinese medicine preparations and highly studied formulas and single herbs, as well as social network analysis of single herbs. There is a significant increase trend in using high-performance liquid chromatography coupled with tandem mass spectrometry related techniques in analysis of commonly used forms of traditional Chinese medicine formulas in the last 3 years. Stringent quality control is of great significance for the modernization and globalization of traditional Chinese medicine, and this bibliometric analysis provided the first and comprehensive summary within this field.

With the extensive using P2P networks, P2P data stream occupied more and more bandwidth, it will affect the performance of the entire Internet. This paper studies the P2P nodes which exchange traffic disorder, through introducing XCP congestion control protocol, designs network region-based exchange unit and flow control strategy to achieve flow control. The simulation results show that the flow control method can ease the P2P data stream.

For WSN, the network node energy is limited, so how to save and even the consumption of the overall energy is an important problem. Clustering is one of the design methods used to manage the network energy consumption efficiently. In this paper, we use genetic simulated annealing algorithm(GSAA) to find an optimal cluster formation and prolong network lifetime. The proposed algorithm takes the nodes position and energy consumption of the network as objective function. Simulation results show that the system's performance have further improved by using GSAA over some existing cluster-based routing protocols.

With the increasingly wide application of Peer-to-Peer, a large amount of data have been accumulated in Peerto-Peer.Nowadays,in improving the search efficiency and system performance, researchers primarily focus on improving the P2P model, these studies have became bottleneckes in some extent. In this paper, data mining technology is applied to P2P network, and some further imrovements based on SWLDRM are done, nodes are clustered based on the features of object stored by K-NN algorithm, applicable decentralized clustering algorithm is designed, new K-Chord modle was constructed, simulation experiments between K-Chord and SWLDRM are done and the result shown that K-Chord has lower maintenance cost and higher search efficiency than SWLDRM.