Based on density functional calculations we predict water ice to attain two new crystal structures with Pbca and Cmcm symmetry at 7.6 and 15.5 Mbar, respectively. The known high-pressure ice phases VII, VIII, X, and Pbcm as well as the Pbca phase are all insulating and composed of two interpenetrating hydrogen bonded networks, but the Cmcm structure is metallic and consists of corrugated sheets of H and O atoms. The H atoms are squeezed into octahedral positions between next-nearest O atoms while they occupy tetrahedral positions between nearest O atoms in the ice X, Pbcm, and Pbca phases.

Abstract The principle of endothermic melting was used to trace the path of phase diagram of foods covering Ice I and Ice III. Fitting the experimental data by parameters of the Simon-Like equations for pure water, R2 values of 0.999 and 0.952 for Ice I and Ice III, respectively, were obtained with a mean error less than 5%. Using this method, phase diagrams of fruit juice and milk in Ice I and Ice III were then obtained, and R2 values in Ice I and Ice III of 0.990 & 0.583 for fruit juice, and 0.991 & 0.886 for milk, respectively, were obtained. Similarly, based on the principle of the melting endothermic of glucose solution and sodium chloride solution under high pressure, pure water and milk could be cooled to pass through different phase transitions regimes. The developed concept and experimental set up are currently can be used for evaluating microbial destruction kinetics as influenced by phase transition HP treatment. Industrial relevance This paper uses the principle of melting endotherm to experimentally obtain the phase diagram of juice and milk, and realize the self-cooling of water and milk. The food (water and milk) can be cooled by the melting endotherm of cooling solution using a simple cooling set-up, and achieve different phase transition profiles with any ordinary high pressure treatment vessel that can operate at 400 MPa. This method overcomes the limitation of previous research studies which rely on more sophisticated and expensive high-pressure- equipment with jacketing and cooling of the pressure chamber with an add on refrigeration source. The developed technique can be used to evaluate microbial destruction as influenced by phase transition, greatly simplifying the experimental process and equipment requirement.

compounds). 2.2 The Freezing Point of Water The freezing point of water is the temperature at which ice … sulfur; the /-L curve shows the effect of pressure on the melting point of the monoclinic form. The M-L curve … curve R-L, which shows the effect of pressure on the melting point of the rhombic solid. In addition to

compounds). 2.2 The Freezing Point of Water The freezing point of water is the temperature at which … M-L curve shows the effect of pressure on the melting point of the monoclinic form. The M-L … R-L, which shows the effect of pressure on the melting point of the rhombic solid. In addition

The melting and freezing of water in a series of mesoporous silica materials with a hexagonal arrangement of unidimensional cylindrical pores and narrow pore-size distribution (MCM-41 with pore diameters from 2.9 to 3.7 nm, and SBA-15 with pore diameters from 4.4 to 11.7 nm) was studied by differential scanning calorimetry (DSC). A lowering of the melting temperature ΔTm = Tmb − Tm(R) up to 50 K was found for water in pores of decreasing radius R. The melting point data can be represented by a modified Gibbs–Thomson equation, ΔTm(R) = K/(R-t), with K = 52 K nm and t = 0.4 nm, in agreement with an earlier study of water in MCM-41 materials of pore width 2 to 4 nm. The value of K agrees with an estimate of the Gibbs–Thomson constant based on thermodynamic data for the normal melting point of ice, and the parameter t can be taken as the thickness of a surface layer of non-frozen water at the pore wall. DSC scans of the freezing of H2O and D2O in partially filled pores of SBA-15 reveal a peak pattern depending on the degree of pore filling ϕ. The different peaks are attributed to different states of the liquid in the pore space, iz. pore water in completely filled regions, and water as an adsorbed film at the pore wall. These two states coexist in a pore filling range ϕmin 1) but exhibits substantial supercooling at ϕ<1. On the other hand, the peak attributed to the freezing of film water exhibits no significant supercooling and is found at temperatures near 237 K, almost indepen

of two persistent degrees on a thermometer, he recounted his experiments showing that the melting point of ice is essentially unaffected by pressure. The degree Celsius is the unit of temperature on the Celsius temperature scale (originally known as the centigrade scale in English), one of two temperature scales used in the International System of Units (SI), the other being the closely related Kelvin scale. The degree Celsius (symbol: °C) can refer to a specific point on the Celsius temperature scale or to a difference or range between two tem The melting and boiling points of water are no longer part of the definition of the Celsius temperature scale. In 1948, the definition was changed to…

expression the difference of vapour- pressures of ice and water in the immediate neighbourhood of the melting - point , but does not observe that the vapour-pressures

Deep engineering of liquid water by charge and impurity injection, charged support, current flow, hydrophobic confinement, or applying a directional field has becoming increasingly important to the mankind toward overcoming energy and environment crisis. One can mediate the processes or temperatures of molecular evaporation for clean water harvesting, HO bond dissociation for H2 fuel generation, solidification for living-organism cryopreservation, structure stiffening for bioengineering, etc., with mechanisms being still puzzling. We show that the framework of "hydrogen bonding and electronic dynamics" has substantiated the progress in the fundamental issues and the aimed engineering. The segmental disparity of the coupled hydrogen bond (O:HO or HB with ":" being lone pair of oxygen) resolves their specific-heat curves and turns out a quasisolid phase (QS, bound at -15 and 4 °C). Electrification shows dual functionality that not only aligns, orders, polarizes water molecules but also stretches the O:HO bond. The O:HO segmental cooperative relaxation and polarization shift the QS boundary through Einstein's relation, ΔΘDx ∝ Δωx, resulting in a gel-like, viscoelastic, and stable supersolid phase with raised melting point Tm and lowered temperatures for vaporization TV and ice nucleation TN. The supersolidity and electro structure ordering provide additional forces to reinforce Armstrong's water bridge. QS dispersion and the secondary effect of electrification such as compression define the TN for Dufour's electro-freezing. The TV depression, surface stress disruption, and electrostatic attraction raise Asakawa's molecular evaporability. Composition of opposite, compatible fields eases the HO dissociation and soil wetting. Progress evidences not only the essentiality of the coupled O:HO bond theory but also the feasibility of engineering water and solutions by programmed electrification.