% 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{Niether:830385,
author = {Niether, Doreen and Afanasenkau, Dzmitry and Dhont, Jan
K.G. and Wiegand, Simone},
title = {{T}hermophoresis and the ‘{O}rigin-of-{L}ife’ concept},
reportid = {FZJ-2017-03938},
year = {2017},
abstract = {Formamide is of special interest in the 'origin-of-life'
concept as it forms 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,
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 [3], 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 [4]. Time dependent studies show that these
high concentrations are reached after 45-90 days. To
understand the dependence of the accumulation on pore
geometry, we derived a heuristic model to illuminate the
process.[1] Pino, S.; Sponer, J. E.; Costanzo, G.; Saladino,
R. and Di Mauro, E.; Life, 5, 372-384, 2015. [2] Baaske, P.;
Weinert, F. M.; Duhr, S.; Lemke, K. H.; Russell, M. J. and
Braun,D.; Proc. Natl. Acad. Sci. USA, 104, 9346-9351,
2007.[3] Miyakawa, S.; Cleaves, H. J. and Miller, S. L.;
Origins Life Evol. Biosphere, 32, 195-208, 2002.[4] Niether,
D.; Afanasenkau, D.; Dhont, J.K.G.; Wiegand, S.; Proc. Natl.
Acad. Sci. USA, 113, 4272–4277, 2016.},
month = {May},
date = {2017-05-25},
organization = {116th General Assembly of the German
Bunsen Society for Physical Chemistry,
Kaiserslautern (Germany), 25 May 2017 -
27 May 2017},
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)6},
url = {https://juser.fz-juelich.de/record/830385},
}