Structural changes in water clusters during methane adsorption

Based on published research on modifying the structure of water and water-containing systems, we assess external influence methods: temperature, magnetic field, light radiation, and their combination. We evaluate changes in the electrophysical, photo- and pH-metric biological, therapeutic, and other properties of water systems using non-destructive electrophysical research methods, i.e., thermometry, pH, laser interference, dynamic light scattering, microelectrophoresis, conductivity, surface tension, dielectric constant, polarimetric measurements, atomic force microscopy, and UV and EPR spectroscopy. The effects of temperature or magnetic field lead to a change in the content and size of water clusters, and physicochemical, biological, therapeutic, and other changes in the properties of water and water-containing systems. The combined effect of a magnetic field and curative mud and the impact of magnetised mineral water have a more pronounced therapeutic effect than only mineral water or curative mud. The data presented indirectly indicate structural changes in water and water-containing systems. We conclude that the primary mechanism of action of a magnetic field, light, or a combination of these factors on water and water-containing systems, including mineral water and therapeutic mud, is a change in the structure of water.

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Methane adsorption onto silicas with various degree of hydrophobicity

Surface ◽

10.15407/surface.2021.13.094 ◽

2021 ◽

Vol 13(28) ◽

pp. 94-126

Author(s):

V. V. Turov ◽

◽

V. M. Gun'ko ◽

T. V. Krupska ◽

◽

...

Keyword(s):

Water Clusters ◽

Chemical Shifts ◽

Physical Adsorption ◽

Bound Water ◽

Adsorbed Water ◽

Methane Adsorption ◽

Methane Hydrates ◽

Degree Of Hydration ◽

Surface Condensation ◽

Wide Range

The methane adsorption onto a hydrated surface of hydrophobic silica AM1 alone and impregnated by arginine, and silica gel Si-100 has been studied using low-temperature 1H NMR spectroscopy. It has been shown that the methane adsorption onto the AM1 surface depends on the degree of hydration and pretreatment type. The maximum adsorption (up to 80 mg/g) is observed for a sample hydrated after complete drying. It has been established that the adsorption is determined by a number of clusters of bound water of small radii. Based on a shape of the temperature dependence of the adsorption, it has been assumed that not only physical adsorption occurs, but also the quasi-solid methane hydrates are formed. It has been established that the amount of methane adsorbed onto a surface of a composite system AM1/arginine under isobaric conditions increases by tens of times (from 0.5 to 80 mg/g) in the presence of pre-adsorbed water pre-adsorbed at the surface. Probable mechanisms of the methane adsorption are physical adsorption on a surface, condensation in narrow voids between silica nanoparticles and nano-scaled (1-10 nm) water clusters, and the formation of solid (clathrate) methane hydrates. Water, adsorbed at a surface in a wide range of hydration, forms various clusters. This water is mainly strongly associated and characterized by chemical shifts in the range dH = 4-6 ppm. The hydrate structures with methane/water are quite stable and can exist even in the chloroform medium. However, in this case, a part of water transforms into a weakly associated state and it is observed at dH = 1.5-2 ppm.

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Structural changes in water and Ar-water clusters under high pressure

Journal of Physics Conference Series ◽

10.1088/1742-6596/635/3/032008 ◽

2015 ◽

Vol 635 (3) ◽

pp. 032008

Author(s):

R Prosmiti ◽

A Vítek ◽

D J Arismendi-Arrieta ◽

R Rodriguez-Cantano ◽

P Villarreal ◽

...

Keyword(s):

High Pressure ◽

Structural Changes ◽

Water Clusters

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Computational investigations of the thermodynamic properties of size-selected water and Ar–water clusters: high-pressure transitions

Physical Chemistry Chemical Physics ◽

10.1039/c4cp04862h ◽

2015 ◽

Vol 17 (14) ◽

pp. 8792-8801 ◽

Cited By ~ 12

Author(s):

Aleš Vítek ◽

D. J. Arismendi-Arrieta ◽

R. Rodríguez-Cantano ◽

R. Prosmiti ◽

P. Villarreal ◽

...

Keyword(s):

Phase Diagram ◽

High Pressure ◽

Monte Carlo ◽

Thermodynamic Properties ◽

Monte Carlo Simulations ◽

Structural Changes ◽

Water Clusters ◽

Parallel Tempering

Phase-diagram of the Ar(H2O)20 cluster from classical parallel-tempering Monte Carlo simulations. Structural changes occur at the indicated A, B and C regions.

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Fine Structural Changes in the Microvasculature of the Mouse Pinna: Aging and Radiation Injury

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100050287 ◽

1974 ◽

Vol 32 ◽

pp. 54-55

Author(s):

S. Phyllis Steamer ◽

Rosemarie L. Devine

Keyword(s):

Structural Changes ◽

Radiation Treatment ◽

Arterial Stenosis ◽

Ultrastructural Changes ◽

Vascular Effects ◽

Microvascular Changes ◽

Surrounding Connective Tissue ◽

Fission Neutrons ◽

Total Body

The importance of radiation damage to the skin and its vasculature was recognized by the early radiologists. In more recent studies, vascular effects were shown to involve the endothelium as well as the surrounding connective tissue. Microvascular changes in the mouse pinna were studied in vivo and recorded photographically over a period of 12-18 months. Radiation treatment at 110 days of age was total body exposure to either 240 rad fission neutrons or 855 rad 60Co gamma rays. After in vivo observations in control and irradiated mice, animals were sacrificed for examination of changes in vascular fine structure. Vessels were selected from regions of specific interest that had been identified on photomicrographs. Prominent ultrastructural changes can be attributed to aging as well as to radiation treatment. Of principal concern were determinations of ultrastructural changes associated with venous dilatations, segmental arterial stenosis and tortuosities of both veins and arteries, effects that had been identified on the basis of light microscopic observations. Tortuosities and irregularly dilated vein segments were related to both aging and radiation changes but arterial stenosis was observed only in irradiated animals.

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