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The environmental adaptabilities of low-density polyethylene (LDPE) play an important role for high-speed trains' reliability and comfort. The weathering of LDPE depends on environment factors, while the complexity of the weathering processes inhibits the evaluation of environmental weathering risks. To elucidate the correlation between weathering and environmental factors, and to predict the weathering risk of target areas of interest, three-year-long natural weathering tests were conducted at twelve natural exposure stations in China. Properties of weathered LDPE were compared and analysed using factor analysis. The fuzzy recognition method based on analytic hierarchy process (AHP) was established and used to predict the weathering risk based on environmental database. The results indicate that the factor scores can partitioned the atmospheric environments into five weathering risk grades. This article used the accumulated cumulative temperature of the daily maximum temperature for weathering risk evaluation, which is more scientific than the annual average temperature widely used and is useful for revealing the difference in LDPE weathering in Turpan and Korla. A comparative chart of LDPE's weathering risk in China was established by this fuzzy recognition method for the first time, which caters to the continuous extension of high-speed railway to new regions. [ABSTRACT FROM AUTHOR]

The deterioration of polycarbonate (PC) depends on various environmental factors. Meanwhile, the complexity of the related weathering processes inhibits the prediction of service life based on the environmental factors. To elucidate the nonlinear correlation between PC weathering and the environmental factors, three-year-long natural weathering tests were conducted at eight experimental stations in China. The relationship between tensile-property data of PC and environmental and pollutant data is analyzed by extra-trees and multilayer perceptron networks implemented in Python. The results indicated that (1) the degradation of PC tensile properties is mainly affected by the experimental period (76.37%), whilst the effect of the environmental or pollutant factors on the degradation is less pronounced (23.63%); (2) the classification accuracy of the trained model on the training set is 91% (91/100), and on the testing set is 72.13% (44/61); and lastly, (3) it is inferred from the error analysis of the classification results that the performance change of polycarbonate in Qionghai and Wuhan is characterized by an initial reduction followed by a slight improvement. Lastly, we show that the proposed method performs well, especially in the case of areas with incomplete data available. [ABSTRACT FROM AUTHOR]

The low anode utilization and large capacity loss of aluminum due to the severe self-corrosion in alkaline electrolyte extremely restrict the practical applications of aluminum-air batteries. The vital challenge lies in the issue to slow down the self-corrosion rate without decreasing the discharge performance of aluminum anode. In this work, the application of zinc sulfate (ZnSO 4) and sodium alginate (SA) as electrolyte additives to mitigate the corrosion of aluminum is investigated by hydrogen evolution test as well as the electrochemical measurements. The results show that zinc sulfate decreases the corrosion rate of aluminum mainly by restraining the cathodic reaction and exerts positive effect on the improvement of discharge performance for aluminum-air batteries. The hybrid ZnSO 4 /SA additive exhibits higher inhibition efficiency for the corrosion of aluminum than single ZnSO 4 or SA, the adsorbed SA stabilizes zinc layer and improves the protective performance. Moreover, the cell voltage is prominently elevated while the discharge capacity increases from 162.46 to 267.41 mAh cm−2 with the dosage of 10 mM ZnSO 4 and 1 g/L SA. A possible model is also proposed to elaborate the influence mechanism of the additive on the self-corrosion behavior and discharge performance of aluminum-air batteries. Image 1 • Self-corrosion rate of aluminum anode was greatly reduced. • Zinc sulfate suppressed corrosion without decreasing electrochemical activity of Al. • Interaction between the additive and aluminum surface was analyzed in detail. • Discharge capacity and voltage of the battery was elevated by using zinc sulfate/SA. • A possible model was proposed to elaborate the influence mechanism of additive. [ABSTRACT FROM AUTHOR]