% IMPORTANT: The following is UTF-8 encoded. This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.
@INPROCEEDINGS{Wiegand:849926,
author = {Wiegand, Simone},
title = {{T}hermophoresis and the ‚{O}rigin-of-{L}ife‘ concept},
reportid = {FZJ-2018-04022},
year = {2018},
abstract = {Formamide is of special interest in the 'origin-of-life'
concept, because it was shown to form a number of prebiotic
molecules under catalytic conditions and at sufficiently
high concentrations [1]. For nucleotides and short DNA
strands, numerical finite-element calculations have shown
that a high degree of accumulation in hydrothermal pores
occurs [2]. Using thermophoretic data of the formamide/water
system measured with Infra-Red Thermal Diffusion Forced
Rayleigh Scattering (IR-TDFRS) we show that the same
combination of thermophoresis and convection in hydrothermal
pores leads to accumulation of formamide up to
concentrations high enough to initiate synthesis of
prebiotic nucleobases. The high degree of formamide
accumulation is due to an unusual temperature and
concentration dependence of the thermophoretic behaviour of
formamide. Starting with a formamide concentration of 10-3
$wt\%,$ estimated to be typical in shallow lakes on early
earth, the accumulation-fold in part of the pores increases
strongly with increasing aspect ratio of the pores, and
saturates to highly concentrated aqueous formamide solutions
of approximately 85 $wt\%$ at large aspect ratios [3]. Time
dependent studies show that these high concentrations are
reached after 45-90 days. Further, we derived a heuristic
model to illuminate the accumulation process and understand
the dependence of the accumulation on pore geometry},
month = {Jul},
date = {2018-07-02},
organization = {University Akron (USA), 2 Jul 2018 - 2
Jul 2018},
subtyp = {Invited},
cin = {ICS-3},
cid = {I:(DE-Juel1)ICS-3-20110106},
pnm = {551 - Functional Macromolecules and Complexes (POF3-551)},
pid = {G:(DE-HGF)POF3-551},
typ = {PUB:(DE-HGF)31},
url = {https://juser.fz-juelich.de/record/849926},
}