The effect of ions on the motion of an oil slug through a charged capillary

Numerous experimental studies have documented that injecting low-salinity water into an oil reservoir can increase the amount of oil recovered. However, owing to the complexity of the chemical interactions involved in this process, there has been much debate over the dominant mechanism causing this effect. In order to further understand one proposed mechanism, multicomponent ionic exchange, we study the motion of an oil slug through a clay pore throat filled with saline water. The pore throat is modelled as a capillary tube connecting two bulk regions of water. We assume that the surfaces of the oil and the capillary are negatively charged and that, due to repulsion between these surfaces, the oil slug is separated from the capillary surface by a thin film of water. Ion interactions at the oil–water and clay–water interfaces are modelled using the law of mass action. By using lubrication theory to describe the thin-film flow in the water layer separating the oil from the clay surface, and the macroscopic flow through the capillary, we derive expressions for the thickness of the wetting film, and the velocity of the oil slug, given a pressure difference across the ends of the capillary. Numerical results show that the thickness of the water layer and the velocity of the oil slug increase as the salinity of the water is reduced, suggesting that this mechanism contributes to the low-salinity effect. An analytical solution is presented in the limit in which the applied pressure is small.

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Paratethys pacing of the Messinian Salinity Crisis: low salinity waters contributing to gypsum precipitation?

10.5194/egusphere-egu2020-11563 ◽

2020 ◽

Author(s):

Wout Krijgsman ◽

Arjen Grothe ◽

Federico Andreetto ◽

Gert-Jan Reichart ◽

Mariette Wolthers ◽

...

Keyword(s):

Surface Water ◽

Saline Water ◽

Water Layer ◽

Alternative Mechanism ◽

Messinian Salinity Crisis ◽

Apparent Paradox ◽

Low Salinity ◽

Gypsum Precipitation ◽

Gypsum Formation ◽

The Mediterranean

During the so-called Messinian Salinity Crisis (MSC: 5.97-5.33 Myr ago), reduced exchange with the Atlantic Ocean caused the Mediterranean to develop into a &#8220;saline giant&#8221; wherein ~1 million km3 of evaporites (gypsum and halite) were deposited. Despite decades of research it is still poorly understood exactly how and where in the water column these evaporites formed. Gypsum formation commonly requires enhanced dry conditions (evaporation exceeding precipitation), but recent studies also suggested major freshwater inputs into the Mediterranean during MSC-gypsum formation. Here we use strontium isotope ratios of ostracods to show that low-saline water from the Paratethys Seas actually contributed to the precipitation of Mediterranean evaporites. This apparent paradox urges for an alternative mechanism underlying gypsum precipitation. We propose that Paratethys inflow would enhance stratification in the Mediterranean and result in a low-salinity surface-water layer with high Ca/Cl and SO4/Cl ratios. We show that evaporation of this surface water can become saturated in gypsum at a salinity of ~40, in line with salinities reported from fluid inclusions in MSC evaporites.

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Arthrophytum scoparium Extract Improves Memory Impairment and Affects Acetylcholinesterase Activity In Mice Brain

Current Pharmaceutical Biotechnology ◽

10.2174/1389201020666191202142226 ◽

2020 ◽

Vol 21 (6) ◽

pp. 480-487

Author(s):

Med A. Smach ◽

Jawhar Hafsa ◽

Bassem Charfeddine ◽

Hedi Dridi ◽

Khalifa Limem ◽

...

Keyword(s):

Antioxidant Activities ◽

Saline Water ◽

Experimental Studies ◽

Chronic Administration ◽

Acetylcholinesterase Activity ◽

Control Group ◽

Pharmacological Activities ◽

Oxidative Damages ◽

Y Maze ◽

Mice Brain

Background: Arthrophytum scoparium (Pomel) Iljin (Amaranthaceae family) has been widely used in traditional Tunisian medicine to treat many disorders such as migraine, headache, and neurological disorders. This study investigates the effect of Arthrophytum scoparium Aqueous Extract (ASAE) on cognitive impairments and oxidative injury induced by galactose (10%) in a mouse model. Materials and Methods: The mice were divided randomly into 4 experimental groups, including the control group (saline water 9 ‰), Galactose group, Scop group (300 mg/kg/d), and Scop+Gal group (300 mg/kg/d). Mice received the corresponding solutions by intraperitoneal injection (i.p.) for 7 days before the Y-maze active tests. Galactose 10% was given to all groups except control and Scop groups, 30 min before the trial. Levels of Acetylcholinesterase Activity (AChE), Ascorbic Acid (AA), Gluthatione (GSH) and Malondialdehyde (MDA) in mice brains were examined. Results: Chronic administration of galactose significantly impaired cognitive performance in Y maze, caused marked oxidative damages and a significant increase in the acetylcholinesterase activity as compared to other groups. On the contrary, ASAE (300 mg/kg) treatment suppressed galactoseinduced oxidative damage by ameliorating the increased levels of GSH and AA. Moreover, ASAE treatment reduced brain AChE activities in the galactose-induced model. Conclusion: These findings suggest that ASAE exerts potent anti-amnesic effects via the modulation of cholinergic and antioxidant activities. The observed pharmacological activities should be further evaluated by detailed experimental studies and validated by clinical trials.

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ИССЛЕДОВАНИЕ МАГНИТОРЕЗИСТИВНЫХ НАНОСТРУКТУР С МАГНИТОСТРИКЦИОННЫМ ЭФФЕКТОМ ДЛЯ УСТРОЙСТВ МАГНИТНОЙ СТРЕЙНТРОНИКИ

Nanoindustry Russia ◽

10.22184/1993-8578.2020.13.3s.420.423 ◽

2020 ◽

Vol 96 (3s) ◽

pp. 420-423

Author(s):

Д.А. Жуков ◽

В.В. Амеличев ◽

Д.В. Костюк ◽

А.И. Крикунов ◽

Д.В. Васильев ◽

...

Keyword(s):

Thin Film ◽

Experimental Studies ◽

Silicon Substrates ◽

Multilayer Nanostructures ◽

Magnetoresistive Effect ◽

Anisotropic Magnetoresistive Effect

Представлены результаты экспериментальных исследований магнитострикционных и магниторезистивных свойств тонкопленочных многослойных наноструктур Ta/FeNiCo/CoFe/Ta и Ta/FeNiCo/CoFeВ/Ta на окисленных кремниевых подложках диаметром 100 мм. Экспериментально установлена зависимость величины анизотропного магниторезистивного эффекта от величины механических деформаций в экспериментальных образцах наноструктур. The paper presents the results of experimental studies of the magnetostriction and magnetoresistive properties of thin-film multilayer nanostructures Ta/FeNiCo/CoFe/Ta and Ta/FeNiCo/CoFeB/Ta on oxidized silicon substrates with a diameter of 100 mm. The dependence of the magnitude of the anisotropic magnetoresistive effect on the magnitude of mechanical strains in experimental samples of nanostructures has been experimentally established.

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Novel Amorphous Carbon Thin Film (ACTF) from Rice Straw to Remove Sodium Ions from Synthetic Saline Water

Advances in Recycling & Waste Management ◽

10.4172/2475-7675.1000111 ◽

2016 ◽

Vol 01 (02) ◽

Cited By ~ 3

Author(s):

Mahmoud Fathy ◽

Mahmoud Ahmed Mousa ◽

TH Abdel Moghny ◽

Abdel Hameed AA El Bellihi ◽

Ahmed E Awadallah

Keyword(s):

Thin Film ◽

Rice Straw ◽

Amorphous Carbon ◽

Saline Water ◽

Sodium Ions ◽

Carbon Thin Film ◽

Amorphous Carbon Thin Film

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Modelling and Experimental Studies of Sorption in the Near Field of a Cementitious Repository

MRS Proceedings ◽

10.1557/proc-176-591 ◽

1989 ◽

Vol 176 ◽

Author(s):

P.L. Brown ◽

A. Haworth ◽

R. McCrohon ◽

S.M. Sharland ◽

C.J. Tweed

Keyword(s):

Near Field ◽

Experimental Studies ◽

Mass Action ◽

Chemical Equilibria ◽

Transport Code ◽

Mass Action Model ◽

Action Model ◽

Modelling Studies ◽

Simple Mass

ABSTRACTA joint experimental and modelling programme is reported, which aims to improve our understanding of sorption processes of radionuclides onto repository materials. Diffusion/sorption experiments of sorption onto cement are described, although results are limited at this stage. The modelling studies use the coupled chemical equilibria and transport code CHEQMATE to simulate some of these experiments. The chemical part of the model is based on a simple mass-action model of sorption. More detailed comparisons will continue when the experiments are terminated, and the samples are sectioned.

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Measurement of Young's Modulus and Poisson's Ratio of Thin Film by Combination of Bulge Test and Nano-Indentation

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.33-37.969 ◽

2008 ◽

Vol 33-37 ◽

pp. 969-974 ◽

Cited By ~ 1

Author(s):

Bong Bu Jung ◽

Seong Hyun Ko ◽

Hun Kee Lee ◽

Hyun Chul Park

Keyword(s):

Thin Film ◽

Mechanical Properties ◽

Young’S Modulus ◽

Poisson’S Ratio ◽

Young's Modulus ◽

Applied Pressure ◽

Indentation Test ◽

Poisson's Ratio ◽

Bulge Test ◽

Nano Indentation

This paper will discuss two different techniques to measure mechanical properties of thin film, bulge test and nano-indentation test. In the bulge test, uniform pressure applies to one side of thin film. Measurement of the membrane deflection as a function of the applied pressure allows one to determine the mechanical properties such as the elastic modulus and the residual stress. Nano-indentation measurements are accomplished by pushing the indenter tip into a sample and then withdrawing it, recording the force required as a function of position. . In this study, modified King’s model can be used to estimate the mechanical properties of the thin film in order to avoid the effect of substrates. Both techniques can be used to determine Young’s modulus or Poisson’s ratio, but in both cases knowledge of the other variables is needed. However, the mathematical relationship between the modulus and Poisson's ratio is different for the two experimental techniques. Hence, achieving agreement between the techniques means that the modulus and Poisson’s ratio and Young’s modulus of thin films can be determined with no a priori knowledge of either.

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Experimental studies in insect parasitism XIV. The haemocytic reaction of a caterpillar to larvae of its habitual parasite

Proceedings of the Royal Society of London Series B Biological Sciences ◽

10.1098/rspb.1966.0062 ◽

1966 ◽

Vol 165 (999) ◽

pp. 155-178 ◽

Cited By ~ 19

Keyword(s):

Foreign Body ◽

Embryonic Development ◽

Chemical Treatment ◽

Blood Cells ◽

Protective Property ◽

Foreign Bodies ◽

Experimental Studies ◽

Ephestia Kuehniella ◽

Main Theme ◽

Ionic Exchange

Although caterpillars of Ephestia kuehniella promptly encapsulate alien parasites and other foreign bodies in their haemocoele, they do not normally encapsulate larvae of their habitual parasite Nemeritis canescens , which develop unhindered and eventually destroy their host. The larva of Nemeritis does not achieve this immunity by repelling the blood cells, or by physically dislodging them. It is immune because it is able to live in the haemocoele of Ephestia without evoking a haemocytic reaction; presumably, that is, because it is not recognized as a foreign body. That ability is due to a property of its surface. So long as its surface remains unaltered, the larva, alive or dead, evokes no haemocytic reaction. When its surface is altered whether by perforation, abrasion, or chemical treatment, the living larva evokes a haemocytic reaction in Ephestia and becomes encapsulated. The protective property of its surface is acquired by the larva very late in its embryonic development, between 62 and 66 hours of age at 25 °C. This is about the same time as, or a little later than, the cuticle of the embryonic larva becomes impermeable to water. Four fat solvents were found to deprive the living larva of its immunity, but they may have affected the protective surface by disrupting the underlying wax layer of the epicuticle. Treatments and substances that did not affect the protective surface give some crude indications of its properties, but its ultimate characterization must be in terms of insect immunology. Observations incidental to the main theme of the paper show that the cuticle of the larva is impermeable to water; that ionic exchange takes place through the anus and wall of the rectum, where some food substances may also be absorbed from the blood of the host; and that the order of formation of the cuticulin and wax layers of the embryonic larva is the same as that in ecdysis from instar to instar in other insects. They also provide information on the longevity of bitten supernumerary larvae.

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Water Salinity Should Be Reduced for Irrigation to Minimize Its Risk of Increased Soil N2O Emissions

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph15102114 ◽

2018 ◽

Vol 15 (10) ◽

pp. 2114 ◽

Cited By ~ 3

Author(s):

Qi Wei ◽

Junzeng Xu ◽

Linxian Liao ◽

Yawei Li ◽

Haiyu Wang ◽

...

Keyword(s):

Saline Water ◽

N2o Emission ◽

Salinity Level ◽

N2o Emissions ◽

Low Salinity ◽

Nitrogen Inputs ◽

Salinity Levels ◽

N2o Fluxes ◽

Moisture Dynamics ◽

Irrigated Soils

To reveal the effect of irrigation salinity on soil nitrous oxide (N2O) emission, pot experiments were designed with three irrigation salinity levels (NaCl and CaCl2 of 1, 2.5 and 4 g/L equivalence, Ec = 3.6, 8.1 and 12.7 ds/m), either for 0 kg N/ha (N0) or 120 kg N/ha (N120) nitrogen inputs. N2O emissions from soils irrigated at different salinity levels varied in a similar pattern which was triggered by soil moisture dynamics. Yet, the magnitudes of pulse N2O fluxes were significantly varied, with the peak flux at 5 g/L irrigation salinity level being much higher than at 2 and 8 g/L. Compared to fresh water irrigated soils, cumulative N2O fluxes were reduced by 22.7% and 39.6% (N0), 29.1% and 39.2% (N120) for soils irrigated with 2 and 8 g/L saline water, while they were increased by 87.7% (N0) and 58.3% (N120) for soils irrigated with 5 g/L saline water. These results suggested that the effect degree of salinity on consumption and production of N2O might vary among irrigation salinity ranges. As such, desalinating brackish water to a low salinity level (such as 2 g/L) before it is used for irrigation might be helpful for solving water resources crises and mitigating soil N2O emissions.

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Reactive Phase Formation in Thin Films: Evolution of Grain Structure

MRS Proceedings ◽

10.1557/proc-403-51 ◽

1995 ◽

Vol 403 ◽

Cited By ~ 5

Author(s):

K. Barmak ◽

C. Michaelsent ◽

J. Rickman ◽

M. Dahmstt

Keyword(s):

Thin Film ◽

Thin Films ◽

Phase Formation ◽

Experimental Studies ◽

Grain Structure ◽

Structure Evolution ◽

Future Research ◽

Polycrystalline Materials ◽

Product Phase ◽

Nucleation Kinetics

AbstractIt is a well known fact that the properties and performance of polycrystalline materials, including polycrystalline thin films, are strongly affected by the grain structure. Therefore, in treating reactive phase formation in these films, it is (or it will inevitably be) necessary to quantify the grain structure of reactant and product phases and its evolution during the course of the reaction. Theoretical models and the conventional view of thin film reactions, however, have been largely extensions, to small and finite dimensions, of theories and descriptions developed for bulk diffusion couples. These models and descriptions primarily focus on the growth stage and to a much lesser extent on the nucleation stage. Consequently, these models and descriptions are not able to treat the development of product phase grain structure. Recent calorimetric investigations of several thin film systems demonstrate the importance of nucleation kinetics (and hence nucleation barriers) in product phase formation and provide quantitative measures of the thermodynamics and kinetics of formation of the product phases, thereby allowing some degree of comparison with reaction models. Furthermore, microstructural investigations of thin-film reactions demonstrate the non-planarity of the growth front and highlight the role of reactant-phase grain boundaries. In this paper, a summary of these experimental studies and recent theoretical treatments, which combine nucleation and growth in an integrated manner, is presented, with particular emphasis on the Nb/Al system. These experiments and models lead to a new view of reactive phase formation and grain structure evolution as one in which the latter is an integral part of the former. Based on this view, directions for future research are discussed.

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