different N concentration的用法和样例：
- At the same time, the screening cultivars and densities, and testing the effect of different N, P, K ratios were conducted.
- Soil NO3--N concentration and accumulation of intercropped faba bean were lower than that of solecropped faba bean at three nitrogen rate.
- There are notable differences of N concentration ,P concentration ,C:N ratio and C:P ratio between leaves on the surface and those 5cm below the surface .
- Eight Dutch surface soils were used in this study to analyse different N fractions in 0.01 molL~(-1) CaCl_2 extracts and percolates at different temperatures.
- A hydroponic experiment was conducted to investigate the effect of different N levels on the growth and anti-cancer glucosinolates content of Chinese kale (Brassica alboglabra).