Carbon-based materials, as electrodes for supercapacitors, have attracted tremendous attention. Therefore, nitrogen-doped porous carbons (NPCs) were prepared through a facile carbonization/activation strategy by treating different mass ratios of melamine–urea–formaldehyde resin and KOH. It is clearly demonstrated that because of the introduction of KOH, the resulting NPCs were shown to have increased specific surface area and a rich pore structure, and the best sample possessed a large specific surface area of 2248 m² g^–1 and high N content, which contributed to the good electrochemical performance for supercapacitors. Accordingly, a three-electrode system assembles NPCs as an electrode using aqueous KOH solution; the specific capacitance was 341 F g^–1 under the current density of 1 A g^–1 and retained a specific capacitance of almost 92% after 5000 cycles. The maximum energy output for a symmetrical solid-state supercapacitor with NPCs as the electrode material was 9.60 W h kg^–1 at 1 A g^–1. NPCs have promising applications on high-performance supercapacitors and other energy-storage devices.

Asphalt pavement cracks easily in low-temperature environments. In order to address the problem, phase-change material (PCM) microcapsules working at 0–10°C are used to replace some of the aggregates in asphalt. In this study, PCM microcapsules with a high-temperature epoxy resin adhesive as reinforcement phase were prepared by using $n$ -tetradecane/tetradecanol as the core material and melamine-urea-formaldehyde as the wall material. The reinforced PCM microcapsules were blended into the asphalt modified by styrene-butadiene-styrene block copolymer (SBS) modified asphalt, the PCM microcapsules were used to replace part of the same amount of the coarse aggregate. The results depict that the reinforced PCM microcapsules can satisfy the requirements of both immersion Marshall test and freeze-thaw splitting test. Above all, asphalt mixtures containing reinforced PCM microcapsules have been proved acceptable via dynamic stability tests. The bending beam rheometer test results imply that asphalt mixture containing PCM microcapsules revealed good crack resistance at low temperatures. Compared with the asphalt mixture sample in the reference experiment, the temperature difference of that containing the reinforced PCM microcapsules could reach 2.1°C, indicating a promising application prospect.