20 research outputs found
Variability of the geothermal gradient across two differently aged magma-rich continental rifted margins of the Atlantic Ocean: the Southwest African and the Norwegian margins
The aim of this study is to investigate the shallow thermal field differences
for two differently aged passive continental margins by analyzing regional
variations in geothermal gradient and exploring the controlling factors for
these variations. Hence, we analyzed two previously published 3-D conductive
and lithospheric-scale thermal models of the Southwest African and the
Norwegian passive margins. These 3-D models differentiate various sedimentary,
crustal, and mantle units and integrate different geophysical data such as
seismic observations and the gravity field. We extracted the
temperature–depth distributions in 1 km intervals down to 6 km below the
upper thermal boundary condition. The geothermal gradient was then calculated
for these intervals between the upper thermal boundary condition and the
respective depth levels (1, 2, 3, 4, 5, and 6 km below the upper thermal
boundary condition). According to our results, the geothermal gradient
decreases with increasing depth and shows varying lateral trends and values
for these two different margins. We compare the 3-D geological structural
models and the geothermal gradient variations for both thermal models and
show how radiogenic heat production, sediment insulating effect, and thermal
lithosphere–asthenosphere boundary (LAB) depth influence the shallow thermal
field pattern. The results indicate an ongoing process of oceanic mantle
cooling at the young Norwegian margin compared with the old SW African
passive margin that seems to be thermally equilibrated in the present day
Ordered semiconducting self-assembled monolayers on polymeric surfaces utilized in organic integrated circuits
We report on a two-dimensional highly ordered self-assembled monolayer (SAM) directly grown on a bare polymer surface. Semiconducting SAMs are utilized in field-effect transistors and combined into integrated circuits as 4-bit code generators. The driving force to form highly ordered SAMs is packing of the liquid crystalline molecules caused by the interactions between the linear alkane moieties and the p-p stacking of the conjugated thiophene units. The fully functional circuits demonstrate long-range order over large areas, which can be regarded as the start of flexible monolayer electronics