Ordered water monolayer that does

A Review of Ordered Water Monolayer That Does Not Completely Wet Water at... 

Viewed macroscopically at room temperature, water always completely wets other water due to the formation of hydrogen bonds. In 2009, based on molecular dynamics simulations, we predicted the phenomenon of a liquid water droplet on a water monolayer, which has been termed as ordered water monolayer that does not completely wet water at room temperature. Recently, this room temperature phenomenon has been observed on many real surfaces in numerical simulations or experiments by research groups worldwide. In this review, we summarize the recent advances in the understanding of this wetting behavior, including the underlying mechanisms and the possible applications. 

The ordered structure of the water monolayer is the key in understanding the phenomenon ordered water monolayer that does not completely wet water at room temperature. Then the question arises Is the ordered water similar to ice or liquid water Based on the thermal analysis method, we... 

Although no hexane molecules were found in the protein s interior for the CTWAT and CTMONO systems, hydrophobic contacts were observed between hexane molecules near the protein surface and hydrophobic side chains in all three systems. Hexane molecules on the protein surface tend to reside in the surface "clefts" formed by the hydrophobic side chains extended into the hexane solvent. At the same time, the hydrophilic residues tended to fold back onto the surface of the protein in order to minimize surface contacts. In our CTMONO simulation, we further observed the water molecules clustered around charged hydrophilic residues, while leaving the hydrophobic residues exposed to the soIvent.(Fig. 1) It has been reported that preferential solvation of the hydrophobic regions of the protein surface by the non-polar solvent is due to the thermodynamically unfavorable formation of a complete monolayer of water in a non-polar solvent. Klibanov and co-workers have also shown that hexane does not strip the water layer - nor does it immobilize the water molecules at the protein/solvent interface. Instead, rearrangements of the water molecules on the protein surface is the more favored process. Our simulations clearly support these experimental observations. 

With fully water-soluble porphyrins, the metal-incorporation rate has been found to be first order in free base, metal, and anion. However, it has been suggested that during incorporation of metals in poorly soluble porphyrins, which would correspond to the situation of polymeric porphyrins, intermediate ( sitting-atop complexes) can be formed. Incorporation kinetics were suggested to be second order in metal and first order in porphyrin. The number of monolayers of polymeric porphyrins occupied by Ni(II) increases with its initial concentration. At trace concentration levels, film thickness is not important because only the first few layers are occupied, and the analyte signal does not depend on film thickness. The concentration levels (10 -10 M) and preconcentration times (40-100 seconds) are not sufficient to exceed the film capacity of monolayer film to incorporate Ni(II). However, for high Ni(II) concentra-... 

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