3 research outputs found
The influence of substrate temperature on growth of para-sexiphenyl thin films on Ir{111} supported graphene studied by LEEM
The growth of para-sexiphenyl (6P) thin films as a function of substrate
temperature on Ir{111} supported graphene flakes has been studied in real-time
with Low Energy Electron Microscopy (LEEM). Micro Low Energy Electron
Diffraction (\mu LEED) has been used to determine the structure of the
different 6P features formed on the surface. We observe the nucleation and
growth of a wetting layer consisting of lying molecules in the initial stages
of growth. Graphene defects -- wrinkles -- are found to be preferential sites
for the nucleation of the wetting layer and of the 6P needles that grow on top
of the wetting layer in the later stages of deposition. The molecular structure
of the wetting layer and needles is found to be similar. As a result, only a
limited number of growth directions are observed for the needles. In contrast,
on the bare Ir{111} surface 6P molecules assume an upright orientation. The
formation of ramified islands is observed on the bare Ir{111} surface at 320 K
and 352 K, whereas at 405 K the formation of a continuous layer of upright
standing molecules growing in a step flow like manner is observed.Comment: 9 pages, 7 figures, Revised Version as accepted for publication in
Surface Scienc
LIFEDATA - a framework for traceable active learning projects
Active Learning has become a popular method for iteratively improving data-intensive Artificial Intelligence models. However, it often presents a significant challenge when dealing with large volumes of volatile data in projects, as with an Active Learning loop. This paper introduces LIFEDATA, a Python- based framework designed to assist developers in implementing Active Learning projects focusing on traceability. It supports seamless tracking of all artifacts, from data selection and labeling to model interpretation, thus promoting transparency throughout the entire model learning process and enhancing error debugging efficiency while ensuring experiment reproducibility. To showcase its applicability, we present two life science use cases. Moreover, the paper proposes an algorithm that combines query strategies to demonstrate LIFEDATA’s ability to reduce data labeling effort