Electrospinning is an effective way to produce nanofibers. The concentration or the corresponding viscosity of the spin solution is one of the most important variables to control the fiber morphology in electrospinning. Jet shaping nanofibers might be divided in two operating modes for different solution viscosity: split thinning and single thinning. From the analysis of jet single thinning, an equation to calculate the velocity of nanofibers depositing on the collector was educed and it was found that the velocity range was very different from the reported result. For the electrospun mats obtained from low solution concentration, the split is observed by scanning electron microscopy (SEM) images. On the other hand, the beads formation in the nanofiber mats can be explained well by jet splitting. The arrangement of nanofibers in the mats is related to the methods of collection, and the cylinder collector gets more ordered mats. This result is proved by so-called break strengths testing and SEM images of the mats obtained from different methods of collection. The concentration or the corresponding viscosity of the spin solution is one of the most important variables to control the fiber morphology in electrospinning. Jet concentration nanofibers might be divided in two operating modes for different solution viscosity: split From the analysis of jet single thinning, an equation to calculate the velocity of nanofibers depositing on the collector was educed and it was found that the velocity range was very different from the reported result. For the electrospun mats obtained from low On the other hand, the beads formation in the nanofiber mats can be explained well by jet splitting. The arrangement of nanofibers in the mats is related to the methods of collection , and the cylinder collector gets more ordered mats. This result is proved by so-called break strengths testing and SEM images of the mats obtained from different methods of collection.