Int J Food Microbiol 2006, 108:178–181.CrossRef 61. Joint Committee on Powder Diffraction Standards: Powder Diffraction File Card 04–0783. Swathmore, AR-13324 order PA: International Center for Diffraction Data; 1987. Competing interests The authors declare that they have no competing interests. Authors’ contributions ERL, RIP, and
REN carried out the experiments. ERL, RIP, REN, JT, RHU, and AM analyzed the data. CIP conducted the plate count experiments. ERL, RIP, JT, and AM developed the conceptual framework, and AM supervised the whole work. ERL, RIP, and AM drafted the paper. All authors read and approved the final manuscript.”
“Background GSK2118436 Carbon nanotube (CNT) arrays for field emission (FE) applications have been extensively studied experimentally and theoretically [1–5]. Various improvements to fabricate well-aligned CNT arrays have been achieved, but non-uniformities are always present. To build precise arrays is expensive and difficult in extending to large areas. Simulation of CNT arrays is cost effective; however, check details simulation of these structures including non-uniformity is rare in the literature. To model non-uniformities in FE, it is necessary to understand their effects on the emission current. The simulation of FE in large domains is notoriously difficult especially in three dimensions, which is necessary in this analysis. The difficulties include long simulation times, large computer memory requirements,
and computational instability. The first analysis of this kind is the recent work of Shimoi and Tanaka . They managed to perform three-dimensional (3D) simulations based on boundary elements that avoided meshing the volume of the 3D domain. They simulated carbon nanofibers
with random position and height to match the emission pattern that they obtained experimentally. In this work, we perform simulations of non-uniform CNTs with dispersions in selleck chemical height, radius, and position in limited ranges and with small CNT aspect ratios aiming to correlate the current from non-uniform arrays with the current expected from perfect arrays. We restrict our analysis to a hemisphere-on-a-post model [4, 6–8], in which the CNTs are regarded as perfect conductors, with a smooth surface and oriented normal to the substrate. In this report, we shall refer to these idealized tubes as CNTs. Methods The CNTs are positioned in a 3 × 3 square array, as shown in Figure 1. We shall explain hereafter that a 3 × 3 square array is an efficient way to perform the simulations. The ith CNT height H i , radius R i , and coordinates (X i ,Y i ) are stochastic variables with expected values (or averages), respectively, equal to h = 10 a.u., r = 1 a.u., and (x i ,y i ) being the center of the ith unit cell in the array. Thus, the default aspect ratio is 10, which is quite small. However, larger aspect ratios cause simulation difficulties that will be discussed later.