A Comment on Fay's Formulae about the Spread of Oil Slick on Water Surface

2013 ◽  
Vol 420 ◽  
pp. 259-262 ◽  
Author(s):  
Zhao Chun Wu
Keyword(s):  
Surface Tension ◽  
Oil Spill ◽  
Water Surface ◽  
Numerical Example ◽  
Second Stage ◽  
Oil Slick ◽  
Spreading Time

Fays formulae of oil spreading in open calm sea are widely quoted in relevant literatures. According to Fays model, the spread of oil slick on water surface can be divided into three different stages, i.e., gravity-inertia stage, gravity-viscous stage and surface tension-viscous stage. Through the analysis of Fays formulae by numerical example, an implied feature of oil spill is revealed that when the oil spill volume is lower than a certain amount, the second stage of oil spreading might not exist. Meanwhile, the numerical example shows that the length of spreading time of oil slick at each stage depends strongly on the oil spill volume.

BREAKUP OF OIL FILM WITH HOLES ON QUIESCENT WATER SURFACE

2005 ◽  
Vol 19 (28n29) ◽  
pp. 1591-1594
Author(s):  
H. J. ZHONG ◽  
H. J. YUAN ◽  
C. B. LEE
Keyword(s):  
Surface Tension ◽  
Flow Visualization ◽  
Water Surface ◽  
Velocity Fields ◽  
Breakup Process ◽  
Oil Film ◽  
Oil Slick ◽  
Flow Maps ◽  
Satellite Drops ◽  
Initial Stage

We experimentally investigate the breakup process of a circular oil film with a hole on water surface using PIV and flow visualization. The hole moves to the bound of the oil slick driven by surface tension, and then the slick breaks into smaller drops. Typical flow maps and velocity fields are given. It is shown that a pair of vortices forms at initial stage, the position of the vortices varies as the hole approaches the bound of the slick. Satellite drops arise when breakup occurs and the size of the satellite drops depend on the shape of the slick.

Immunoferritin localization of intracellular antigens in positively stained frozen sections

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).

scholarly journals Adsorption Properties of Hydrocarbon and Fluorocarbon Surfactants Ternary Mixture at the Water-Air Interface

Molecules ◽  
2021 ◽  
Vol 26 (14) ◽  
pp. 4313
Author(s):  
Bronisław Jańczuk ◽  
Katarzyna Szymczyk ◽  
Anna Zdziennicka
Keyword(s):  
Surface Tension ◽  
Water Surface ◽  
Standard Free Energy ◽  
Ternary Mixtures ◽  
Free Energy Of Adsorption ◽  
Interface Tension ◽  
Air Interface ◽  
Surface Excess Concentration ◽  
Tail Water ◽  
Triton X

Measurements were made of the surface tension of the aqueous solutions of p-(1,1,3,3-tetramethylbutyl) phenoxypoly(ethylene glycols) having 10 oxyethylene groups in the molecule (Triton X-100, TX100) and cetyltrimethylammonium bromide (CTAB) with Zonyl FSN-100 (FC6EO14, FC1) as well as with Zonyl FSO-100 (FC5EO10, FC2) ternary mixtures. The obtained results were compared to those provided by the Fainerman and Miller equation and to the values of the solution surface tension calculated, based on the contribution of a particular surfactant in the mixture to the reduction of water surface tension. The changes of the aqueous solution ternary surfactants mixture surface tension at the constant concentration of TX100 and CTAB mixture at which the water surface tension was reduced to 60 and 50 mN/m as a function of fluorocarbon surfactant concentration, were considered with regard to the composition of the mixed monolayer at the water-air interface. Next, this composition was applied for the calculation of the concentration of the particular surfactants in the monolayer using the Frumkin equation. On the other hand, the Gibbs surface excess concentration was determined only for the fluorocarbon surfactants. The tendency of the particular surfactants to adsorb at the water-air interface was discussed, based on the Gibbs standard free energy of adsorption which was determined using different methods. This energy was also deduced, based on the surfactant tail surface tension and tail-water interface tension.

scholarly journals Marine Oil Slick Detection Using Improved Polarimetric Feature Parameters Based on Polarimetric Synthetic Aperture Radar Data

2021 ◽  
Vol 13 (9) ◽  
pp. 1607
Author(s):  
Guannan Li ◽  
Ying Li ◽  
Yongchao Hou ◽  
Xiang Wang ◽  
Lin Wang
Keyword(s):  
Synthetic Aperture Radar ◽  
Oil Spill ◽  
Synthetic Aperture ◽  
Polarimetric Synthetic Aperture Radar ◽  
Synthetic Aperture Radar Data ◽  
Marine Oil ◽  
Oil Spill Detection ◽  
Oil Slick ◽  
Feature Parameters ◽  
Aperture Radar

Marine oil spill detection is vital for strengthening the emergency commands of oil spill accidents and repairing the marine environment after a disaster. Polarimetric Synthetic Aperture Radar (Pol-SAR) can obtain abundant information of the targets by measuring their complex scattering matrices, which is conducive to analyze and interpret the scattering mechanism of oil slicks, look-alikes, and seawater and realize the extraction and detection of oil slicks. The polarimetric features of quad-pol SAR have now been extended to oil spill detection. Inspired by this advancement, we proposed a set of improved polarimetric feature combination based on polarimetric scattering entropy H and the improved anisotropy A12–H_A12. The objective of this study was to improve the distinguishability between oil slicks, look-alikes, and background seawater. First, the oil spill detection capability of the H_A12 combination was observed to be superior than that obtained using the traditional H_A combination; therefore, it can be adopted as an alternate oil spill detection strategy to the latter. Second, H(1 − A12) combination can enhance the scattering randomness of the oil spill target, which outperformed the remaining types of polarimetric feature parameters in different oil spill scenarios, including in respect to the relative thickness information of oil slicks, oil slicks and look-alikes, and different types of oil slicks. The evaluations and comparisons showed that the proposed polarimetric features can indicate the oil slick information and effectively suppress the sea clutter and look-alike information.

Aerospace monitoring in the problems for assessment of geoecological risks for accidental spills of oil and petroleum products

2021 ◽  
pp. 72-85
Author(s):  
Виктор Геннадьевич Аковецкий ◽  
Алексей Викторович Афанасьев ◽  
Анжела Асхатовна Ильченко
Keyword(s):  
Oil Spill ◽  
Oil And Gas ◽  
Negative Impact ◽  
Experimental Testing ◽  
Oil Products ◽  
Oil Pipeline ◽  
Oil Slick ◽  
Research Risks ◽  
Aerospace Monitoring ◽  
Oil And Oil Products

Оценка геоэкологических рисков на объектах нефтегазового комплекса непосредственно связана с обеспечением безопасности территорий, на которых они расположены. Особенно тяжелые последствия воздействия на экологическое состояние территорий оказывают аварийные разливы нефти и нефтепродуктов. Решение данного класса задач требует оценки уровня аварийного разлива и его классификации с позиций возникновения чрезвычайной ситуации. В статье рассмотрена возможность замены традиционных визуальных методов оценки разливов на разработанные автоматизированные и автоматические способы, использующие для решения задач классификации материалов аэрокосмических съемок. Приведены результаты автоматической классификации изображений мониторинговых наблюдений, которые имели место при аварийном разливе дизельного топлива в г. Норильске, аварии танкера на морской акватории о. Маврикий и аварии сухопутного нефтепровода. Полученные результаты показали работоспособность разработанных методов и возможность их использования в задачах инвентаризации и паспортизации аварийных разливов нефти на суше и акваториях. Purpose. The aim of this work is to ensure the environmental safety of the territories where the accidental spills of oil and oil products have occurred. They have a significant negative impact on the environment of land and water areas. To minimize their impact and eliminate the consequences, an “emergency” regime is introduced in Russia. Depending on the level of the oil spill, it may cover both the territory of a separate facility and a region, and the entire state as a whole. Methods. Traditionally, an estimate of the level of a spill is determined based on the mass of the spilled oil through visual observations from aircraft or ground measurements at selected points. This approach does not allow an accurate assessment of the total area of pollution, the nature of pollution inside the oil slick, as well as the dynamics of its spread over time. To eliminate these limitations, it is proposed to use systems of aerospace monitoring observations and automatic measurements of oil slick parameters: area, composition and mass. To solve this problem, the method of “comparison with the reference standard” was used. Here, samples of color gradations of oil and oil product spill spots proposed in the Bonn Agreement of 2004 were prepared as reference standards. Results. The method was implemented using the experimental software complex AGIR-TM (Aerospace, Geoinformatics, Research, Risks-Technological Modules) which was developed at the Department of Geoecology of the Gubkin Russian State University of Oil and Gas (NRU). During the experimental testing of this method, the work was carried out to assess the accidental spill in the following cases diesel fuel in Norilsk (2020), oil on a tanker in the water area of Mauritius (2020) and oil in an oil pipeline (2012, 2017). The method provides the localization of the area spills along with the color correction (normalization), classification of the composition of oil and oil products and the through account of the investigated processes. The work results in determination for the area of the oil and oil products spill, its composition and weight. Conclusions. The article shows the relevance of solving problems related to the problem of liquidation of emergency spills of oil and oil products at the facilities of the oil and gas complex. The main approaches to aerospace monitoring observations and automatic interpretation of spill parameters are considered. The proposed approach is based on the use of “digital twins” that implement the transition from manual (visual) to automated and automatic modes for determining the parameters of an oil spill: area, composition and mass. The results presented in the article showed the efficiency of the proposed method and the possibility of its use in the tasks of assessing geoecological risks associated with accidental spills of oil and oil products on land and in water areas.

scholarly journals Methodological scheme for ranking interval expert estimates of the territories hydrocarbon potential

2019 ◽  
pp. 35-39
Author(s):  
Mykhailo Popov ◽  
Oleksandr Zaitsev ◽  
Iryna Piestova
Keyword(s):  
Hydrocarbon Potential ◽  
Software System ◽  
Interval Estimates ◽  
Numerical Example ◽  
Second Stage ◽  
A Priority ◽  
Two Stages ◽  
Hydrocarbon Deposit ◽  
Interval Valued

The problem of priorities establishing for expert interval-valued estimations when experts hold the opposite opinion is considered. The whole group of expert estimates is subdivided into subgroups, first of which provides the probability of the deposit presence, and the second one provides the probability of deposit missing. A ranking methodology for interval expert estimates of the territories’ hydrocarbon potential, consisting of two stages, is proposed. At the first stage, an estimates formed by two subgroups of experts are separately aggregated by optimization. Two aggregated interval estimates of the corresponding hypotheses probabilities are obtained as a result. In the second stage, a priority estimate is determined by comparing the results. A numerical example of the test territory evaluating for a hydrocarbon deposit presence was calculated. Interval-valued estimates by five experts were used in this example for the hypotheses of hydrocarbons presence/missing. Various metrics of the distance between interval values were used to calculate persistent minima of aggregating estimates. The results of the calculations indicate the hypothesis’ priority of a hydrocarbon deposit presence within the study area. The proposed methodology for ranking interval-valued expert estimates can be used in the “Geologist’s Computer Assistant” software system.The problem of priorities establishing for expert interval-valued estimations when experts hold the opposite opinion is considered. The whole group of expert estimates is subdivided into subgroups, first of which provides the probability of the deposit presence, and the second one provides the probability of deposit missing. A ranking methodology for interval expert estimates of the territories’ hydrocarbon potential, consisting of two stages, is proposed. At the first stage, an estimates formed by two subgroups of experts are separately aggregated by optimization. Two aggregated interval estimates of the corresponding hypotheses probabilities are obtained as a result. In the second stage, a priority estimate is determined by comparing the results. A numerical example of the test territory evaluating for a hydrocarbon deposit presence was calculated. Interval-valued estimates by five experts were used in this example for the hypotheses of hydrocarbons presence/missing. Various metrics of the distance between interval values were used to calculate persistent minima of aggregating estimates. The results of the calculations indicate the hypothesis’ priority of a hydrocarbon deposit presence within the study area. The proposed methodology for ranking interval-valued expert estimates can be used in the “Geologist’s Computer Assistant” software system.

scholarly journals Experimental analysis on the optimal excitation wavelength for fine-grained identification of refined oil pollutants on water surface based on laser-induced fluorescence

2021 ◽  
Author(s):  
Ming Xie ◽  
Yunpeng Jia ◽  
Ying Li ◽  
Xiaohua Cai ◽  
Kai Cao
Keyword(s):  
Oil Spill ◽  
Theoretical Basis ◽  
Water Surface ◽  
Laser Induced Fluorescence ◽  
Excitation Wavelength ◽  
Refined Oil ◽  
Fine Grained ◽  
Optimal Excitation ◽  
Oil Spill Identification

Abstract Laser-induced fluorescence (LIF) is an effective, all-weather oil spill identification method that has been widely applied for oil spill monitoring. However, the distinguishability on oil types is seldom considered while selecting excitation wavelength. This study is intended to find the optimal excitation wavelength for fine-grained classification of refined oil pollutants using LIF by comparing the distinguishability of fluorometric spectra under various excitation wavelengths on some typical types of refined-oil samples. The results show that the fluorometric spectra of oil samples significantly vary under different excitation wavelengths, and the four types of oil applied in this study are most likely to be distinguished under the excitation wavelengths of 395 nm and 420 nm. This study is expected to improve the ability of oil types identification using LIF method without increasing time or other cost, and also provides theoretical basis for the development of portable LIF devices for oil spill identification.

Pilgrim Trust Lecture, Molecular layers

1939 ◽  
Vol 170 (940) ◽  
pp. 1-39 ◽  
Keyword(s):  
Surface Tension ◽  
Olive Oil ◽  
Water Surface ◽  
Organic Molecules ◽  
Critical Thickness ◽  
Clean Water ◽  
Oily Contamination ◽  
Molecular Layers ◽  
Modern Work

If fragments of camphor are placed upon a clean water surface they move about vigorously and may even be made to propel toy boats. The late Lord Rayleigh (1890 a, 1890 c) found that these movements stopped rather abruptly if the surface tension of the water was lowered by 21 dynes/cm. by oily contamination of the surface. The amount of olive oil needed for this purpose was surprisingly small, corresponding to a thickness of only 16 A (16 x 10 -8 cm.). Miss Pockels (1891) proved that any amount of olive oil less than enough to give a critical thickness of about 10 A had no effect whatever on the surface tension of water, but above this limit the surface tension decreased rapidly as the amount of oil was increased. Only 5 g. of olive oil would be needed to cover an acre of water surface with a film of this critical thickness. Miss Pockels also showed that accidental contamination of the surface, which had previously complicated nearly all observations of surface-tension phenomena, could be eliminated by using a trough filled to the brim with water, and sweeping impurities off the surface by the motion of barriers which rested on the edges of the trough. This use of movable barriers to confine films, to compress them or to remove them from the surface, laid the foundation for nearly all the modern work with films on water. The early theories of surface tension had been developed by physicists (Thomas Young 1805; Laplace, Gauss, etc.) who either treated liquids as continuous fluids between whose elements of volume forces acted, or considered only spherical molecules which exerted upon one another forces that varied as a function of the distance between molecular centres. Such theories naturally could not take into account the wealth of knowledge that had been accumulated by organic chemists regarding the structures of organic molecules.

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