The fractional complex transform is suggested to convert a fractional differential equation with Jumarieʼs modification of Riemann–Liouville derivative into its classical differential partner. Understanding the fractional complex transform and the chain rule for fractional calculus are elucidated geometrically.
A new perturbation technique called linearized perturbation method is proposed. Contrary to the traditional perturbation techniques, the unperturbed equations is obtained by linearizing the original nonlinear equation, not by setting ϵ = 0. Therefore, the obtained results are valid not only for small parameter, but also for very large values of ϵ. The present theory is processed as simple as the straightforward expansion, while omits the secular terms completely.
Nanofibers with high surface-to-volume ratio are of significant applications. This paper proposes a novel method for fabrication of particle-like beaded nanofibers and their daughter nanofibers, which are ejected from the surface of charged jets. Polyvinyl alcohol/ash solution is used in the electrospinning process.
No abstract is provided for this article.
Bubble electroblowing is employed by combining bubble-electrospinning with airflow to prepare silk fibroin nanofibers. The result indicated that not only nanofibers but also droplet-like beads were formed. Unlike traditional beads conjugating fibers, droplet-like beads accompanied fibers by sides. The average diameter of fibers is 572 nanometers while the special beads is 1909 nanometers.
Recently instability in electrospinning has received much attention. This letter applies magnetic field to electrospinning. The induced Ampere force can dramatically reduce the radius of the whipping circle.
Ashes are used as additives to strengthen bubble walls using the Hall–Petch effect and, as a result, a larger bubble can be produced in the bubble-spinning process, and it can last for a longer period. The fiber morphology can be easily controlled by the amount of ashes added. Two-dimensional nanobelts can be fabricated when the ashes ratio reaches a certain threshold.
Bubble electrospinning exhibits profound prospect of industrialization of macro/ nano materials. Starch is the most abundant and inexpensive biopolymer. With the drawbacks of poor strength, water resistibility, thermal stability and processability of pure starch, some biodegradable synthetic polymers such as poly (lactic acid), polyvinyl alcohol were composited to electrospinning. To the best of our knowledge, composite nanofibers of polyvinyl alcohol/starch from bubble electrospinning have never been investigated. In the present study, nanofibers of polyvinyl alcohol/starch were prepared from bubble electrospinning. The processability and the morphology were affected by the weight ratio of polyvinyl alcohol and starchy. The rheological studies were in agreement with the spinnability of the electrospinning solutions.
In this paper, a novel method called variational iteration method is proposed to solve nonlinear partial differential equations without linearization or small perturbations. In this method, a correction functional is constructed by a general Lagrange multiplier, which can be identified via variational theory. An analytical solution can be obtained from its trial-function with possible unknown constants, which can be identified by imposing the boundary conditions, by successively iteration.
Governing equations for one-dimensional ionic polymer–metal composites are reviewed and then cast into the framework of a variational statement. Starting from a trial-Lagrangian, a generalized functional is derived through a systematic procedure of the semi-inverse method proposed by Ji-Huan He. All field equations and boundary conditions are cast into Euler equations of the obtained functional, leading to much convenience in incorporating analytical and numerical approaches.
No abstract is provided for this article.
No abstract is provided for this article.
No abstract is provided for this article.
Recently Nappa obtains a Gurtin-type variational principle for micromorphic thermoelasticity. However, the use of convolutions is of course restricted to the linear case, which sets a limit to the rang of applicability. This paper establishes a classic variational principles for the discussed problem by the semi-inverse method.
In the paper, the writer introduces the structure and property of BG214Z type carding machine researched and manufactured by them. The machine is used in nonwovens carding process, and it can match with napping machine of Cermany Dilo Company.
The pull-in instability is the inherent property of a micro-electromechanical system (MEMS) when the voltage is larger than its threshold value. Recently, a fractal MEMS system was proposed to overcome the pull-in instability with great success, and it has opened a total new path for the so-called pull-in stability. This paper suggests a pull-in plateau, a novel concept for qualifying the pull-in stability. The plateau’s basic properties are elucidated, and the effect of the fractal dimensions on the plateau width is elucidated, and the paper concludes that there exists a critical condition for an ever pull-in stability when both the acceleration and the speed of the system equal zero.
