Be due to a great variety and minute particle size and multivariate shape and great difference in particle's size, which brings difficulty to separation of pollens.
但由于花粉种类繁多、颗粒微小、不同种类花粉形状多变且大小相差很大，这给花粉的分选带来极大困难。
2
Addition of certain additives into low viscous non-gel sieving matrices is an efficient and simple method to overcome the difficulty of filling capillaries and enhance DNA separation.
在低粘度的无胶筛分介质中加入某种添加剂是一种有效且简单的克服填充困难和提高DNA分离性能的方法。
3
The improvement to the method of variable combination makes the problem of dual variable separation in geometric programming with a multi difficulty degree simple and easy to solve.