The coverage-dependent phase behavior of molecular films of alcohols (CH3(CH2)n-2CH2OH, denoted as CnOH) on mercury was studied for chain lengths 8 < or = n < or = 28, using surface tensiometry and surface specific X-ray methods. Phases with surface-normal-oriented molecules are found at high coverage, showing the CS, S, and LS phases found also on water. Phases comprising surface parallel molecules, which do not exist on water, are found here at low coverage. For the lowest coverage a two-dimensional gas phase is found, followed, upon increasing the coverage, by an n-dependent sequence of condensed phases of up to four layers of surface-parallel molecules before converting to the surface-normal phases. In contrast with the surface-normal phases, all of the surface-parallel phases are found to lack long-range order in the surface-parallel direction. Adsorption energies are derived from the phase diagram for the alkyl chain and the alcohol headgroup.
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http://dx.doi.org/10.1021/la0497954 | DOI Listing |
J Chem Phys
January 2025
Institute of Thermodynamics and Thermal Process Engineering, University of Stuttgart, Pfaffenwaldring 9, D-70569 Stuttgart, Germany.
Effective potential methods, obtained by applying a quantum correction to a classical pair potential, are widely used for describing the thermophysical properties of fluids with mild nuclear quantum effects. In case of strong nuclear quantum effects, such as for liquid hydrogen and helium, the accuracy of these quantum corrections deteriorates significantly, but at present no simple alternatives are available. In this work, we solve this issue by developing a new, three-parameter corresponding-states principle that remains applicable in the regions of the phase diagram where quantum effects become significant.
View Article and Find Full Text PDFSci Rep
January 2025
Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang, 110016, China.
To achieve rapid and stable detumbling of a space noncooperative satellite, an adaptive variable admittance control method for the manipulator is proposed and verified through simulation study and the ground experiment. The control block diagram of the proposed method is presented, and the adaptive variable admittance compliant detumbling control model is established. The proposed controller includes the fixed admittance controller in manipulator task space, the adaptive pose compensator for the grasping point on docking ring, and the damping adaptive regulator based on manipulator joint angular velocity, and the stability is proven by the Lyapunov method.
View Article and Find Full Text PDFChaos
January 2025
Departamento de Física, Universidade Federal de Santa Catarina, Florianópolis 88040-900, Santa Catarina, Brazil.
The presence of chaos is ubiquitous in mathematical models of neuroscience. In experimental neural systems, chaos was convincingly demonstrated in membranes, neurons, and small networks. However, its effects on the brain have long been debated.
View Article and Find Full Text PDFHealth Res Policy Syst
January 2025
University College London, London, United Kingdom.
Background: The deteriorating mental health of children and young people in the United Kingdom poses a challenge that services and policy makers have found difficult to tackle. Kailo responds to this issue with a community-based participatory and systemically informed strategy, perceiving mental health and well-being as a dynamic state shaped by the interplay of broader health determinants. The initiative works to explore, define and implement locally relevant solutions to challenges shaping the mental health and well-being of young people.
View Article and Find Full Text PDFJ Phys Chem B
January 2025
Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States.
Molten salts are promising candidates in numerous clean energy applications, where knowledge of thermophysical properties and vapor pressure across their operating temperature ranges is critical for safe operations. Due to challenges in evaluating these properties using experimental methods, fast and scalable molecular simulations are essential to complement the experimental data. In this study, we developed machine learning interatomic potentials (MLIP) to study the AlCl molten salt across varied thermodynamic conditions ( = 473-613 K and = 2.
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