Adsorption of a Diverse Set of Organic Vapors on the Bulk Water Surface

There exists an optimal amount of solvent (generally water) that can be added to the slurry phase reaction between solid reactants; the reactivity and efficiency of such reactions are different from those without solvent or those with large amount of solvent. Obviously, the solvent plays a crucial role in the process of the reaction, and it is the key to the understanding of unique reactivity and high efficiency of such slurry phase reactions. The water molecule absorbed on the surface of solid reactants, which is called bound water, has uniquely different properties compared with bulk water. Surface hydroxylation resulting from bound water greatly influences the chemical activity of the surface, which could be playing a role as catalyst or as the initialization point for further reactions, so that the reactants can react easily and fast under a simple reaction condition.

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Propensity, free energy contributions and conformation of primary n-alcohols at a water surface

Physical Chemistry Chemical Physics ◽

10.1039/d1cp02818a ◽

2021 ◽

Author(s):

Victor Ekholm ◽

Carl Caleman ◽

Jochen S. Hub ◽

Malin Wohlert

Keyword(s):

Free Energy ◽

Water Surface ◽

Primary Alcohol ◽

Surface Adsorption ◽

Bulk Water ◽

Hydrophobic Tail

The transition of primary alcohol molecules from bulk water to the surface is driven by entropy, increasing linearly with length of the hydrophobic tail. The enthalpy of surface adsorption is nearly invariant with increasing length of the molecule.

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Evaporation above a bulk water surface using an oil lamp inspired highly efficient solar-steam generation strategy

Journal of Materials Chemistry A ◽

10.1039/c8ta03280g ◽

2018 ◽

Vol 6 (26) ◽

pp. 12267-12274 ◽

Cited By ~ 87

Author(s):

Xuan Wu ◽

Limin Wu ◽

Jeanette Tan ◽

George Y. Chen ◽

Gary Owens ◽

...

Keyword(s):

Water Surface ◽

Bulk Water ◽

Steam Generation ◽

Evaporation Surface ◽

Highly Efficient ◽

Solar Steam Generation ◽

Oil Lamp

Inspired by a kerosene oil lamp, a highly efficient solar-evaporation system with the evaporation surface located above the bulk water surface is realized.

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Immunoferritin localization of intracellular antigens in positively stained frozen sections

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010008170x ◽

1978 ◽

Vol 36 (2) ◽

pp. 168-169

Author(s):

K. T. Tokuyasu

Keyword(s):

Surface Tension ◽

Water Surface ◽

Thin Layers ◽

The Other ◽

Positive Staining ◽

Frozen Sections ◽

The Past ◽

Ultrathin Frozen Sections ◽

Definition Of

During the past investigations of immunoferritin localization of intracellular antigens in ultrathin frozen sections, we found that the degree of negative staining required to delineate u1trastructural details was often too dense for the recognition of ferritin particles. The quality of positive staining of ultrathin frozen sections, on the other hand, has generally been far inferior to that attainable in conventional plastic embedded sections, particularly in the definition of membranes. As we discussed before, a main cause of this difficulty seemed to be the vulnerability of frozen sections to the damaging effects of air-water surface tension at the time of drying of the sections.Indeed, we found that the quality of positive staining is greatly improved when positively stained frozen sections are protected against the effects of surface tension by embedding them in thin layers of mechanically stable materials at the time of drying (unpublished).

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Etching of Polymers by Oxygen Plasma

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100101797 ◽

1968 ◽

Vol 26 ◽

pp. 408-409

Author(s):

Virgil Peck ◽

W. L. Carter

Keyword(s):

Molecular Weight ◽

Oxygen Plasma ◽

Flow Time ◽

Microscopical Study ◽

Surface Layers ◽

Organic Vapors ◽

Sample Position ◽

Accuracy Of Measurement ◽

Bulk Polymers ◽

Electron Microscopical

Any electron microscopical study of the morphology of bulk polymers has throughout the years been hampered by the lack of any real ability to produce meaningful surface variations for replication. True etching of polymers should show crystalline and amorphous regions in some form of relief. The use of solvents, acids, organic vapors, and inert ion bombardment to etch samples has proved to be useful only in limited applications. Certainly many interpretations of these results are subject to question.The recent use of a radiofrequency (R. F.) plasma of oxygen to degrade and remove organic material with only minor heating has opened a new possibility for etching polymers. However, rigid control of oxygen flow, time, current, and sample position are necessary in order to obtain reproducible results. The action is confined to surface layers; the molecular weight of the polymer residue after heavy etching is the same as the molecular weight of the polymer before attack, within the accuracy of measurement.

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STEM measurement of subcellular water distributions

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100148678 ◽

1993 ◽

Vol 51 ◽

pp. 568-569

Author(s):

R.D. Leapman ◽

S.Q. Sun ◽

S-L. Shi ◽

R.A. Buchanan ◽

S.B. Andrews

Keyword(s):

Water Content ◽

Internal Standard ◽

Dry Weight ◽

Dry Mass ◽

Scanning Transmission Electron Microscope ◽

Dark Field ◽

Bulk Water ◽

Inelastic Electron ◽

Scanning Transmission ◽

Annular Dark Field

Recent advances in rapid-freezing and cryosectioning techniques coupled with use of the quantitative signals available in the scanning transmission electron microscope (STEM) can provide us with new methods for determining the water distributions of subcellular compartments. The water content is an important physiological quantity that reflects how fluid and electrolytes are regulated in the cell; it is also required to convert dry weight concentrations of ions obtained from x-ray microanalysis into the more relevant molar ionic concentrations. Here we compare the information about water concentrations from both elastic (annular dark-field) and inelastic (electron energy loss) scattering measurements.In order to utilize the elastic signal it is first necessary to increase contrast by removing the water from the cryosection. After dehydration the tissue can be digitally imaged under low-dose conditions, in the same way that STEM mass mapping of macromolecules is performed. The resulting pixel intensities are then converted into dry mass fractions by using an internal standard, e.g., the mean intensity of the whole image may be taken as representative of the bulk water content of the tissue.

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