The induction of a graphite-like phase on diamond films by a Fe-coating/post-annealing process to improve their electron field emission properties

[[abstract]]The electron field emission (EFE) process for diamondfilms was tremendously enhanced by Fe-coating and post-annealing processes. Microstructural analysis indicates that the mechanism for the improvement in the EFE process is the formation of nanographites with good crystallinity that surround the Fe (or Fe3C) nanoclusters. Presumably the nanographites were formed via the reaction of Fe clusters with diamondfilms, viz. by the dissolution of carbons into Fe (or Fe3C) clusters and the reprecipitation of carbon species to the surface of the clusters, a process similar to the growth of carbon nanotubes via Fe clusters as catalyst. Not only is a sufficiently high post-annealing temperature (900°C) required but also a highly active reducing atmosphere (NH3) is needed to give a proper microstructure for enhancing the EFE process. The best EFE properties are obtained by post-annealing the Fe-coated diamondfilms at 900°C in an NH3 environment for 5 min. The EFE behavior of the films can be turned on at E 0 = 1.9 V/μm, attaining a large EFE current density of 315 μA/cm2 at an applied field of 8.8 V/μm (extrapolation using the Fowler–Nordheim model leads to J e = 40.7 mA/cm2 at a 20 V/μm applied field).[[incitationindex]]SCI[[booktype]]紙本[[booktype]]電子

Hookworm infestation, an old but not vanished disease

AbstractHookworms, together with other helminthes infestations, were serious health problems in Taiwan before. With improvements in public health and medicine, the prevalence of parasite infestations drops significantly and current attention has been shifted to foreign laborers coming from the Southeast Asia. Herein we reported a case of hookworm infestation who presented as subacute diarrhea. Initially, only peripheral eosinophilia was revealed. Anti-helminth treatment, but not the immunosuppressant for eosinophilic gastroenteritis, was given when the hookworm ova were finally harvested after repeated stool examinations. Please remember the old diseases when you meet a patient with gastrointestinal complaints and peripheral eosinophilia, especially when there are intermittent skin atopic manifestations. Repeated parasite ova checks with concentration method are necessary in acute stage, especially when the worm burden is not heavy

Existence theorems for a crystal surface model involving the p-Laplace operator

The manufacturing of crystal films lies at the heart of modern nanotechnology. How to accurately predict the motion of a crystal surface is of fundamental importance. Many continuum models have been developed for this purpose, including a number of PDE models, which are often obtained as the continuum limit of a family of kinetic Monte Carlo models of crystal surface relaxation that includes both the solid-on-solid and discrete Gaussian models. In this paper we offer an analytical perspective into some of these models. To be specific, we study the existence of a weak solution to the boundary value problem for the equation - \Delta e^{-\mbox{div}\left(|\nabla u|^{p-2}\nabla u\right)}+au=f, where $p>1, a>0$ are given numbers and $f$ is a given function. This problem is derived from a crystal surface model proposed by J.L.~Marzuola and J.~Weare (2013 Physical Review, E 88, 032403). The mathematical challenge is due to the fact that the principal term in our equation is an exponential function of a p-Laplacian. Existence of a suitably-defined weak solution is established under the assumptions that $p\in(1,2], \ N\leq 4$, and $f\in W^{1,p}$. Our investigations reveal that the key to our existence assertion is how to control the set where -\mbox{div}\left(|\nabla u|^{p-2}\nabla u\right) is $\pm\infty$