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Reducing carbon emissions and increasing carbon sinks are key strategies to effectively remove greenhouse gases from the atmosphere. Assessing the current carbon emission status and predicting future carbon emission scenarios could help formulate effective regional carbon emission reduction targets. However, it is necessary to enhance the carbon sink capacity of terrestrial ecosystems and improve forest management methods to promote greenhouse gas absorption. In this study, the spatiotemporal characteristics and dynamic evolution of fossil fuel CO 2 (FFCO 2) emissions in China from 2000 to 2019 were analyzed using the standard deviation ellipse, kernel density of emissions, and Theil index. A backpropagation (BP) neural network optimized with a genetic algorithm (GA) was used to predict FFCO 2 emission during 2020–2030. The biomass increment methodology was used to predict the potential carbon sinks generated by Chinese Certified Emission Reduction (CCER) carbon-sink forestry projects during 2020–2030. The results showed that China's FFCO 2 emissions exhibited a gradual increasing trend during 2000–2019, with an average annual growth rate of 6.29%. China's FFCO 2 emissions show a greater distribution on the southeastern coast than in the northwestern interior. The GA-BP prediction shows that China's FFCO 2 emissions will continue to fluctuate and increase between 2020 and 2030. The potential of carbon sinks will be 0.69 × 108 Mg C generated by the CCER carbon-sink forestry projects during 2020–2030, which could offset 0.56% of FFCO 2 emissions. In the future, imbalances in regional development should be considered when formulating carbon-reduction strategies. Moreover, using carbon-sink of forestry projects of CCER to balance economic development including poverty eradication and environmental conservation should be considered. Specifically, establishing a methodology of projects for the management of natural forests' carbon-sink will be an important future strategy. • China's FFCO 2 emissions rose in volatility with an average growth rate of 6.29%. • The spatial differences of FFCO 2 emissions are gradually narrowing. • FFCO 2 emissions will continue to rise in the future. • Carbon-sink forestry project is ideal approach to offset carbon emission. • The Methodology of Forests Management for natural forest should be focused. [ABSTRACT FROM AUTHOR]

Based on the wear analysis of a propeller hub bearing, wear tests are designed under different marine environments to illustrate wear failure mechanisms. The results reveal that the wear failure characteristics of the propeller hub bearing are primarily abrasive wear, accompanied by adhesion and oxidation wears, and plastic deformation. These results agree well with the wear morphologies of the torsional fretting wear tests under starvation lubrication. The wear tests confirm that the wear failure of the propeller hub bearing is owing to the coexistence of multiple wear mechanisms, which is attributed primarily to the superimposed wear behaviors induced by loading, continuous fretting wear, and starvation lubrication in the local contact areas. Hence, the negative effects of interfacial micro-protrusion adhesion and fracture during oil lubrication are difficult to eliminate. Moreover, The uneven radial loads of the contact surfaces of the propeller hub bearing also exhibit a significant influence on the thickness and formation of the oil film at the friction interface. [Display omitted] • Wear failure mechanisms of bearing coated with NAB alloys had been studied. • The designed wear tests were conducted by a self-assemble tribological platform. • Wear failure morphologies of bearing and wear tests results had been discussed. • Physical model at the different wear stages was established. [ABSTRACT FROM AUTHOR]