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[ Objective ] In order to enrich the diversity of periphytic diatoms in the Yangtze River Basin , systematic sampling was carried out in this study. [ Methods ] The microstructure and ultrastructure of the diatom samples were observed by light microscope and scanning electron microscope. [ Results ] A newly recorded species of diatom from China , Livingstonia palatkaensis Prasad & Nienow , was found from Jin􀆴e Mountain in Yueyang City , Hunan Province. This genus was also the first to be discovered in China. [ Conclusion ] The discovery of this newly recorded species provided new information on the geographical distribution of this genus.

This paper studies a combination forecasting model with strong adaptability and high dimension to evaluate value of patents, and verifies the model empirically in the research. Through the AHP analysis, five necessary factors that affect the value of patents are discovered, which come from both the characteristic factors of the patent itself and the institutional characteristic factors that attempt to transform the patent. We’ve constructed a state space model through some data that can already obtain the added value of its patent through the Hejun value evaluation model and deployed the state space model in the artificial intelligence data space to have the neural network training. Another part of the known data is used to empirically verify this model, and it is found that the data fits well. Not only can the model be used for patent conversion institutions to evaluate patents, but also for patent holders to evaluate patent conversion institutions.

This work aims at improving the medium- and low-temperature strength of Al2O3-C unfired slide plate materials. Sucrose, nickel nitrate hexahydrate, ethyl orthosilicate and oxalic acid aqueous solution with the mass ratio of 1:0. 15:2. 7:0 0.03 were added to ethanol aqueous solution in turn, and dried at 110 °C for 18 h, obtaining SiC polymer precursor. Then, tabular corundum, α-Al2O3 micropowder and flake graphite were used as the main raw materials, added with the SiC polymer precursor and Zn powder, pressed at 150 MPa into green bodies of 150 mm x25 mm x25 mm, cured at 180 °C for 24 h, and then heat treated at 600, 800, 1 000, 1 200 and 1 400 °C for 3 h under carbon embedded conditions. The effects of the SiC polymer precursor and Zn powder on the properties of Al2O3-C materials were studied. The results show that the Al2O3-C material has the optimal comprehensive performance when adding 4.5% SiC polymer precursor and 1.5% Zn powder; at low temperatures, Zn powder melts and forms metal bonding phases in the material system; at medium temperatures, the pyrolysis reaction of the SiC polymer precursor and the catalysis of Zn powder after evaporation make the system form SiC fiber bonding phases. They work together to give Al2O3-C unfired slide plate material high medium- and low-temperature strength, which overcomes the failure problem caused by the low strength in application. [ABSTRACT FROM AUTHOR]