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1

Statistics of underwater acoustic signals scattered by the rough water surface covered with a layer of oil substances

100%
Pogorzelski S. J.
Oceanologia
|
1989
|
tom 27
2

Radial oscillations of gas bubbles covered with a monolayer of surface-active substances in the near-surface sea layer

100%
Pogorzelski S. J.
Oceanologia
|
1988
|
tom 25
3

The influence of crude oil spills on the sea surface on ultrasound scattering

100%
Pogorzelski S. J.
Oceanologia
|
1991
|
tom 31
4
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Content available

Thermoelastic surface properties of seawater in coastal areas of the Baltic Sea

63%
Boniewicz-Szmyt K., Pogorzelski S. J.
Oceanologia
|
2016
|
tom 58
|
nr 1
5
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Content available

Kinetics of marine surfactant adsorption at an air-water interface. Baltic Sea studies

63%
Pogorzelski S. J., Kogut A. D.
Oceanologia
|
2001
|
tom 43
|
nr 4
The paper contains the results of studies of natural surface film adsorption kinetics carried out in inland waters and in shallow offshore regions of the Baltic Sea during 2000–01 under calm sea conditions. The novel approach presented here for the adsorption dynamics is based on the mixed kinetic-diffusion model and analyses of the surface pressure-time plots at short (t → 0) and long (t→∞) adsorption time intervals. Values of the effective relative diffusion coefficient Deff/D (= 0.008 − 0.607) and energy barrier for adsorption Ea/RT (= 0.49 − 7.10) agree well with the data reported for model non-ionic surfactant solutions of pre-cmc concentrations. Wind speed is one of the factors affecting the adsorption barrier via the increased surface pressure of the natural film exposed to wind shear stress (∼ U10 2),a nd enters the relation Ea/RT = 1.70U10 1/3.
6
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Adsorptive properties of natural water surfactant films. Dead Vistula catchment water studies

63%
Pogorzelski S. J., Kogut A. D.
Oceanologia
|
2003
|
tom 45
|
nr 3
The paper contains the results of natural film experiments carried out on inland waters in the Dead Vistula (Martwa Wisła) catchment area during 1999–2002 using the integrated Langmuir trough-Wilhelmy plate system,w hich ‘cuts out’ an undisturbed film-covered area without any physicochemical sample processing. The static film parameters result from the generalized scaling procedures applied to the surface pressure-area isotherms. They appear to correspond well to observations of the film composition (Alim, MW, Eisoth),film solubility and the miscibility of its components (via R, ΔSc and y factors),and surface concentration (πeq, Γeq). A novel approach is presented for the adsorption dynamics on the basis of the mixed kinetic-diffusion model and analyses of the dynamic surface pressure plots,whic h leads to the determination of the effective relative diffusion coefficient Deff/D and activation energy barrier Ea/RT . There is reason to believe that certain classes of film-forming components or ‘end-members’ may dominate the static and dynamic surface properties. Some of these substances can be used as source-specific surface-active biomarkers to trace temporal and spatial changes due to environmental factors or the production of biological matter. The concept was tested for the Dead Vistula river and its tributaries. The results demonstrate that natural films are a complex mixture of biopolymeric molecules covering a wide range of solubilities,sur face activities and molecular masses with an apparent structural film architecture. Such studies could lead to the development of film structure parameters – indicators of ecosystem quality and the state of the environment.
7
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Static and dynamic properties of surfactant films on natural waters

63%
Pogorzelski S. J., Kogut A. D.
Oceanologia
|
2001
|
tom 43
|
nr 2
The paper contains the results of natural surface film surface pressure – area experiments carried out in inland waters and shallow offshore regions of the Baltic and Mediterranean Seas during 1990–99 under calm water conditions using the Langmuir trough – Wilhelmy filter paper plate system, which ‘cuts out’ an undisturbed film-covered sea area without any initial physico-chemical sample processing. The limiting specific area Alim (268–3157 ˚A2/molecule−1) and mean molecular mass (0.65–9.7 kDa) of microlayer surfactants were determined from the 2D virial equation of state applied to the isotherms. Film structure signatures were derived from π − A isotherm hysteresis and application of the 2D polymer scaling theory. The stress-relaxation measurements revealed a two-step relaxation process at the interface with characteristic times τ1 (1.1–2.8) and τ2 (5.6–25.6) seconds suggesting the presence of diffusion-controlled and structural organization relaxation phenomena. The results demonstrate that natural films are a complex mixture of biomolecules covering a wide range of solubilities, surface activity and molecular mass with an apparent structural organization exhibiting a spatial and temporal variability.
8

The surface rheological properties of organic films on rain water: rain rate correction

51%
Mazurek A. Z., Pogorzelski S. J., Kogut A. D.
Polish Journal of Environmental Studies
|
2006
|
tom 15
|
nr 5
769-776
The presented procedure allows one to recover the film properties present originally at the raindrop surface from the Langmuir trough data supplemented with simultaneously taken rain event characteristics (rain rate and rain drop diameter distribution). It requires the partitioning effect of the surfactant molecules between the surface and bulk phases to be estimated where the entering quantities are: the partitioning coefficient Kp=r/c and a degree of the rain water interfacial system area development Ar/Vr evaluated here using fatty acid concentrations as model input data. The latter parameter depends on particular rain event signatures. The concept is quantified using the Langmuir trough film and disdrometer data on a set of rain water events observed at Gdańsk, Poland in May 2002.
9
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Adsorption of natural surfactants present in sea waters at surfaces of minerals: contact angle measurements

51%
Mazurek A., Pogorzelski S. J., Boniewicz-Szmyt K.
Oceanologia
|
2009
|
tom 51
|
nr 3
377-403
The wetting properties of solid mineral samples (by contact angles) in original surfactant-containing sea water (Gulf of Gdańsk,Ba ltic) were characterised under laboratory conditions on a large set (31 samples) of well-classified stones of diverse hydrophobicity using the sessile drop (ADSA-P approach),ca ptive bubble and inclined plate methods. An experimental relation between the static contact angle θeq and stone density ρ was obtained in the form θeq = Bρ + C,wher e B = 12.23 ± 0.92, C = −(19.17 ± 0.77),an d r2 = 0.92. The histogram of θeq distribution for polished stone plates exhibited a multimodal feature indicating that the most abundant solid materials (hydrophilic in nature) have contact angles θeq = 7.2,10. 7,15. 7 and 19.2◦,whic h appear to be applicable to unspecified field stones as well. The contact angle,a pH-dependent quantity,ap pears to be a sensitive measure of stone grain size,e.g . granite. The captive bubble method gives reproducible results in studies of porous and highly hydrophilic surfaces such as stones and wood. The authors consider the adsorption of natural sea water surfactants on stone surfaces to be the process responsible for contact angle hysteresis. In the model,an equation was derived for determining the solid surface free energy from the liquid’s surface tension γLV; it also enabled the advancing θA and receding θR contact angles of this liquid to be calculated. Measurements of contact angle hysteresis Δθ(= θA − θR) with surfactant-containing sea water and distilled water (reference) on the same stone surfaces allowed the film pressure ΔΠ (1.22 to 8.80 mJ m−2), solid surface free energy ΔγS (−17.03 to −23.61 mJ m−2) and work done by spreading ΔWS (−1.23 to −11.52 mJ m−2) to be determined. The variability in these parameters is attributed to autophobing,an effect operative on a solid surface covered with an adsorptive layer of surfactants. The wetting behaviour of solid particles is of great importance in numerous technological processes including froth flotation,d emulgation,an ti-foaming procedures and the coal industries. It is believed that the approach presented here and the examples of its application to common sea water/solid mineral systems could be successfully adapted to optimise several surfactant-mediated adsorption processes (see below) of practical value in natural water ecology.
10

Structural characterization of fatty acid films on rain water: a scaling approach using physical attributes

51%
Mazurek A. Z., Pogorzelski S. J., Kogut A. D.
Polish Journal of Environmental Studies
|
2006
|
tom 15
|
nr 6
A complete compositional or structural description of naturally-occurring surfactants on rain water is not currently feasible. A main limitation of previous work has been the lack of means for correlating force-area char­acteristics with the chemical makeup of the films. Instead of analyzing the chemical composition of rain water film-forming organics, it is postulated here to introduce the novel scaling procedures (2D virial equation of state and 2D polymer film scaling theory) applied to the surface pressure-area (n-A) isotherms and surface pressure- temperature (n-T) isochors and resulting from generalized physical formalisms modified to a multicomponent surfactant film. A set of the introduced structural film state parameters (n, r, Alim, Eisoth, y, R, Mw, Ps) could become sensitive indicators for surface-active source-specific organic matter pathway tracing, where the measurement of surfactant concentration and chemical analyses are avoided. The concept is quantified using the Langmuir trough film and disdrometer data on a set of rain water events observed in Gdańsk, Poland in May 2002.
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