Nitrogen is the inert gases, low expansion coefficient, not easily with the environmental temperature rise for a long time, can maintain normal tire pressure, greatly reduce the flat tire.
氮气是惰性气体，膨胀系数低，不轻易随环境温度上升而上升，可较长时间维持正常胎压，大大降低爆胎几率。
2
The wavelet coefficient curves of temperature and precipitation on different time scales reveal that the long periodical variation trend is quite different from the short.
气温和降水在不同时间尺度上的小波系数变化曲线图揭示了气候的长期和短期变化趋势有很大不同。
3
Advantages: good toughness, low friction coefficient of the ruby head, long life.