Kun Shan University

About: Kun Shan University is a education organization based out in Tainan City, Taiwan. It is known for research contribution in the topics: Heat transfer & Thin film. The organization has 1992 authors who have published 2928 publications receiving 45685 citations. The organization is also known as: Kūnshān Kējì Dàxué.

Thermally induced optical effects in double-coated optical fibers by viscoelastic theory

Abstract: A viscoelastic theory is adopted to analyze the optical effects in double-coated polymeric optical fibers subjected to thermal loadings. A closed-form solution of the microbending loss and refractive index changes obtained by using the Laplace transformation method is presented. To obtain the solution, the compatibility conditions of displacement at interfaces and Lame's formula for the stress components are used. The results are initially identical to those obtained by the elastic analysis, and then decrease gradually as time progresses. To minimize the microbending loss, the polymeric coatings were suitably selected, so that the Young's moduli, Poisson's ratios, and viscosities of the primary and secondary coatings would decrease. Furthermore, selecting suitable primary and secondary coatings with lower Young's moduli, Poisson's ratios, and viscosities reduce the changes of refractive index in the glass fiber.

The effect of a transverse electric field on the electronic properties of an armchair carbon nanoscroll

Abstract: In this work, we use the tight-binding model to study the low-energy electronic properties of carbon nanoscrolls subject to the influences of a transverse electric field. A carbon nanoscroll can be considered as an open-ended spirally wrapped graphene nanoribbon. The inter-wall interactions will alter the subband curvature, create additional band-edge states, modify the subband spacing or energy gap, and separate the partial flat bands. Furthermore, the energy band symmetry about the Fermi level is lifted by such interactions. The truncated Archimedean spiral ρ = r a θ +r is used to describe the spiral structures of carbon nanoscrolls. The energy gap is found to oscillate significantly with r, and exhibits complete energy gap modulations. With the inclusion of a transverse electric field, the band structures are further altered. Inter-wall hoppings will cause electron transfers between different atoms leading to distortions of the electron wavefunctions. The main features of the energy dispersions are dir...

Imaging of Magnetic Nanoparticles Using a Second Harmonic of Magnetization With DC Bias Field

Abstract: We have developed a method to improve the detection sensitivity for the magnetization ${M}$ of magnetic nanoparticles (MNPs) using a high Tc superconducting quantum interference device magnetometer. The ${M}$ response of MNP to an applied magnetic field ${H}$ ( ${M}$ – ${H}$ characteristics) can be divided into a linear region and a saturation region, which are separated at a transition point ${H}_{k}$ . When applying an excitation ac magnetic field ( ${H}_{\rm ac}$ ) and an additional dc bias field ${H}_{\rm dc} {=} {H}_{k}$ , the second harmonic of M reaches a maximum due to the nonlinearity of its ${M}$ – ${H}$ characteristics. This harmonic is stronger than any other harmonics, including a third harmonic. The advantage of using the second harmonic response is that the response can be measured even in a small field ${H}_{\rm ac}$ . The ${M}$ response of MNP was systematically analyzed and experimentally demonstrated. For conventional detection using a third harmonic, the amplitude of the ${H}_{\rm ac}$ must be larger than the threshold level, which is almost the same as ${H}_{k}$ . Detection methods using a second harmonic can be applied to magnetic particle imaging. We finally demonstrate the construction of a 1-D image of two separated bottle-shaped MNP samples using the method with a lock-in amplifier.