This title appears in the Scientific Report :
2016
Please use the identifier:
http://hdl.handle.net/2128/12829 in citations.
Thermophoretic accumulation in hydrothermal pores
Thermophoretic accumulation in hydrothermal pores
The thermophoretic properties of aqueous formamide solutions as a function of concentration and temperature are studied by means of Infra-Red Thermal Diffusion Forced Rayleigh Scattering. Comparing the results with empirical concepts to describe the temperature dependence of aqueous solutions [1] an...
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Personal Name(s): | Niether, Doreen (Corresponding author) |
---|---|
Afanasenkau, Dzmitry / Dhont, Jan K.G. / Wiegand, Simone | |
Contributing Institute: |
Weiche Materie; ICS-3 |
Imprint: |
2016
|
Conference: | 4th International Soft Matter Conference, Grenoble (France), 2016-09-12 - 2016-09-16 |
Document Type: |
Poster |
Research Program: |
Functional Macromolecules and Complexes |
Link: |
OpenAccess OpenAccess |
Publikationsportal JuSER |
The thermophoretic properties of aqueous formamide solutions as a function of concentration and temperature are studied by means of Infra-Red Thermal Diffusion Forced Rayleigh Scattering. Comparing the results with empirical concepts to describe the temperature dependence of aqueous solutions [1] and molecular dynamics simulations of formamide water mixtures [2] it becomes apparent that the system only adheres to the empirical equation in a dilute state and deviates when formamide-formamide interactions take place at higher concentrations.Formamide is of special interest in the ‘origin-of-life’ concept as it has been shown that a number of prebiotic molecules such as purine, adenine, cytosine and 4(3H)-pyrimidinone form from formamide under catalytic conditions and at sufficiently high concentrations [3]. For nucleotides and short DNA strands it has been shown with numerical finite-element calculations that a high degree of accumulation in hydrothermal pores occurs [4]. Using our thermophoretic data on the formamide/water system, we show that the same combination of thermophoresis and convection in hydrothermal pores leads to accumulation of formamide up to concentrations where nucleobases are formed. 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 [5], 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. References[1] S. Iacopini, R. Rusconi and R. Piazza, Eur. Phys. J. E, 19, (2006) [2] M. D. Elola and B. M. Ladanyi, J. Chem. Phys., 125, (2006) [3] S. Pino, J.E. Sponer, G. Costanzo, R. Saladino and E. Di Mauro, Life, 5, (2015) [4] P. Baaske, F. M. Weinert, S. Duhr, K. H. Lemke, M. J. Russell and D. Braun, P. Natl. Acad. Sci. USA, 104, (2007)[5] S. Miyakawa, H. J. Cleaves and S. L. Miller, Origins Life Evol. Biosphere, 32, (2002) |