Here we show an intriguing phenomenon in the bubble electrospinning process that the ruptured film might be stripped upwards by an electronic force to form a very thin and long plate-like strip, which might been received in the metal receiver as discontinuous backbone-like wrinkled materials, rather than smooth nano-fibers or microspheres. The processes are called the bubble electrospinning. The electronic force can be replaced by a blowing air, and the process is called as the blown bubble spinning. We demonstrate that the size and thickness of the ruptured film are the crucial parameters that are necessary to understand the various observations including beads and nanoporous materials. We identify the conditions required for a ruptured film to form discontinuous structure, and a critical width of the ruptured film to form a cylindrical fiber, above which a long and thin plate-like strip might be obtained, and a criterion for oscillatory jet diameter, which leads to bead morphology of the obtained fibers. The space of the adjacent beads depends on the fiber size. We anticipate our assay to be a starting point for more sophisticated study of the bubble electrospinning and the blown bubble spinning and for mass-production of both nanofibers and nanoscale discontinuous materials

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The purpose of this paper is to employ an analytical approach to a two-dimensional viscous flow with a shrinking sheet. A comparative study of the variational iteration algorithm-II (VIM-II) and the Adomian decomposition method (ADM) are discussed. Both approaches have been applied to obtain the solution of a two-dimensional viscous flow due to a shrinking sheet. This study outlines the significant features of the two methods. Comparison is made with the ADM to highlight the significant features of the VIM-II and its capability of handling completely integrable equations. Through careful investigation of the iteration formulas of the earlier variational iteration algorithm (VIM), we find unnecessary repeated calculations in each iteration. To overcome this shortcoming, we suggest the VIM-II, which has advantages over other iteration formulas, such as the VIM, and the ADM. Further iterations can produce more accurate results and decrease the error.

In this paper, we will consider the Laplace decomposition method (LDM) for finding series solutions of nonlinear oscillator differential equations. The equations are Laplace transformed and the nonlinear terms are represented by He's polynomials. The solutions are compared with the numerical (fourth-order Runge-Kutta) solution and the solution obtained by the Adomian decomposition method. The suggested algorithm is more efficient and easier to handle as compared to the numerical method. The results illustrate that LDM is an appropriate method in solving the highly nonlinear equations.