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With the continuous development of modern industry, environmental problems accompanied by heavy metal Pb(II) and organic dyes become increasingly apparent, and the development of associated detection/removal materials has important practical significance thus. In this work, a novel biomass (diphenolic acid and furfurylamine)-based, polyamide-sulfonate cross-linked polymer (PA-df-OBSC) was successfully constructed. Further characterization of PA-df-OBSC indicated that the chemical structure of PA-df-OBSC consists of multiple N/O/S-containing molecular fragments as amide, tertiary amine, carboxylic acid, sulfonate ester and sulfonate acid. Such structural characteristic endows PA-df-OBSC dual functional application prospect. PA-df-OBSC can be applied as an enrichment-type Pb(II) electrochemical probe due to its specific complexation for Pb(II). The modified glassy carbon electrode (GCE) with PA-df-OBSC as active modifier presented a wide detection range (0.1–30 μmol/L) and low detection limit (1.31 × 10−8 M) for Pb(II). Besides, PA-df-OBSC also showed selective adsorption for cationic dye methylene blue (MB), with the maximum adsorption capacity up to 521.72 mg/g. [ABSTRACT FROM AUTHOR]

Ag–SnO2Sb2O3 materials prepared by internal oxidation technology have excellent electrical properties. Here Ag–SnO2Sb2O3 materials are fabricated by four kinds of different oxidation ways. Influence of oxidation way on microstructure and oxides distribution is investigated and the formation mechanism of Ag–SnO2Sb2O3 materials is discussed. The oxidation effect of billet oxidation in air + Ag2O is the best and the oxides distribution is the most uniform and the physical properties (relative density: 97.2%, hardness: 57 Hv03 and electrical conductivity: 12.3 Ms/m) are also the best in the four kinds of oxidation ways. [ABSTRACT FROM AUTHOR]

The existing adaptive growth technique deducted the optimization iteration formula according to the condition named Karush-Kuhn-Tucker condition. It is high efficiency and good, which is aimed to strain energy and bound to the volume against optimization problem of stiffener distribution for plate and shell structures. However, different optimization iteration formula, which deducted by different kinds of problem, is poor and difficult to generalize, especially for the optimization problems with more than one constraint. Against with the lack of adaptive growth technique, a new method that is moving asymptotes（MMA） is suggested by this article and the adaptive growth technique is applied to truss structure topology optimization design. The design of typical truss structures with single constraint and multiple constraints is discussed, and the multi load cases are studied. The results of numerical examples show that the proposed method can obtain clear information of rod distribution and dimension, and has high design efficiency and good applicability. It is convenient for practical machining and has a good application prospect.

As one of core components of machine tool,the reliability of spindle is very important for improving machine tool quality. According to spindle performance degradation mechanism analysis,the acoustic emission signal is used to monitor and study the performance state of spindle. A reliability evaluation method is proposed for the long-life and less failure sample problem based on machine tool degradation path models. At last,this method is used to solve the machine tool spindle reliability assessment,which integrates virtual augmented sample method. It effectiveness and practicability is proved through experiment results.