agar is a gelling biopolymer that can be extracted from cell wall of some red algae. in this present, response surface methodology was used to investigate the procedure of agar melting point and gelling temperature from cultural algae of gracilariopsis persica. independent variables, alkalinity concentration (2, 3.2, 5, 6.8, -8%), extraction temperature (90, 96, 105, 114, 120°c) and extraction ...

The ability of the most popular models of methanol (H1, OPLS, L2, and L1) for the prediction of the solid-solid and the solid-fluid equilibria was analyzed in detail in this work by using molecular simulation. The three solid phases (α, β, and γ) detected experimentally as being thermodynamically stable, as well as the fluid phase, were considered for the calculations. It turns out that all the...

The carboxyl-functionalized phosphonium ionic liquid (IL), [HCTMP][Tf(2)N], enabled the directed nucleation of monomeric or dimeric uranyl(vi) compounds. This new IL is the first carboxyl-functionalized IL which is liquid at room temperature and exhibits a wider electrochemical window and lower melting point than its ammonium analogue.

Molecular dynamic simulations were performed for ice I(h) with a free surface by using four water models, SPC/E, TIP4P, TIP4P/Ice, and TIP4P/2005. The behavior of the basal plane, the primary prismatic plane, and of the secondary prismatic plane when exposed to vacuum was analyzed. We observe the formation of a thin liquid layer at the ice surface at temperatures below the melting point for all...

Recent molecular dynamics simulation results have increased conceptual understanding of the grazing and the ploughing friction at elevated temperatures, particularly near the substrate's melting point. In this commentary we address a major constraint concerning its experimental verification.

C. WYLENZEK*, J. TRÜBENBACH†, P. GOHL†, G. WILDHARDT†, S. ALKINS‡, M. B. FAUSETT‡, J. DECKER§, D. STEINBERGER†,¶ *Hunsrueck Klinik, Simmern, Germany Bioscientia Center for Human Genetics, Ingelheim, Germany Landstuhl Regional Medical Center, Landstuhl, Germany §Department of Hematology and Oncology, Johannes Gutenberg-University, Mainz, Germany –Institute for Human Genetics, Justus-Liebig Unive...

We show that there exists an Efimov-like three strand DNA bound state at the duplex melting point and it is described by a renormalization group limit cycle. A nonperturbative renormalization group is used to obtain this result in a model involving short range pairing only. Our results suggest that Efimov physics can be tested in polymeric systems.

An analytical solution shows that a competition between bond order loss and the associated bond strength gain of the lower coordinated atoms near the edge of a surface dictates the mechanics of the surface and, hence, a nanosolid. Bond order loss lowers the activation energy for atomic dislocation, whereas bond strength gain enhances the energy density or mechanical strength in the region near ...

Ice plays crucially important roles in various phenomena because of its abundance on Earth. However, revealing the dynamic behavior of quasi-liquid layers (QLLs), which governs the surface properties of ice crystals at temperatures near the melting point, remains an experimental challenge. Here we show that two types of QLL phases appear that exhibit different morphologies and dynamics. We dire...

Water exhibits a maximum in density at normal pressure at 4 degrees above its melting point. The reproduction of this maximum is a stringent test for potential models used commonly in simulations of water. The relation between the melting temperature and the temperature of maximum density for these potential models is unknown mainly due to our ignorance about the melting temperature of these mo...