Predicting the impact of salt mixtures on the air-water interfacial behavior of PFAS

2021 ◽  
pp. 151987
Author(s):  
Song-Thao Le ◽  
Yi Gao ◽  
Tohren C.G. Kibbey ◽  
William C. Glamore ◽  
Denis M. O'Carroll
Keyword(s):  
Interfacial Behavior ◽  
Salt Mixtures ◽  
The Impact

scholarly journals Effect of Hydrothermal Exposure on Interfacial Stress Transfer in Graphite/Epoxy Composites loaded in Compression

1996 ◽  
Vol 5 (6) ◽  
pp. 096369359600500 ◽  
Author(s):  
Maher S. Amer ◽  
Linda S. Schadler
Keyword(s):  
Fragment Length ◽  
Stress Transfer ◽  
Interfacial Stress ◽  
Epoxy Composites ◽  
Shear Stresses ◽  
Interfacial Behavior ◽  
The Impact

The effect of hydrothermal exposure on the ability of the interface to transfer shear stresses in graphite/epoxy composites under compression is reported. Hydrothermal exposure caused a drop in the ability of the interface to transfer shear stresses from 130 to 15 MPa and increase in the average fragment length from 80 to 1000 μm. The impact of hydrothermal exposure on the composite interfacial behavior is compared with that for composites loaded in tension. The results showed that the interfacial degradation is more severe for composites loaded in compression.

Study on the slag-metal interfacial behavior under the impact of bubbles in different sizes

2021 ◽  
Author(s):  
Sheng Chang ◽  
Zongshu Zou ◽  
Jianhua Liu ◽  
Mihaiela Isac ◽  
Xiangkun Elvis Cao ◽  
...  
Keyword(s):  
Interfacial Behavior ◽  
The Impact

Experimental Investigation of the Effects of Asphaltene Stability on Interfacial Behavior of Live-Reservoir-Fluid Systems

SPE Journal ◽  
2018 ◽  
Vol 24 (01) ◽  
pp. 21-31 ◽  
Author(s):  
Ram R. Ratnakar ◽  
Cesar A. Mantilla ◽  
Birol Dindoruk
Keyword(s):  
Contact Angle ◽  
Detection System ◽  
Water Systems ◽  
Wettability Alteration ◽  
Sharp Change ◽  
Interfacial Behavior ◽  
Asphaltene Precipitation ◽  
Reservoir Conditions ◽  
The Impact ◽  
Live Oil

Summary Wettability alteration resulting from asphaltene precipitation in a reservoir affects rock/fluid interactions that have a potential impact on oil production, recovery, and flow in the production network. The current predictive wettability models are inherently inaccurate and do not consider asphaltene stability. This study investigates the impact of pressure-depletion-induced asphaltene precipitation on interfacial tension (IFT) and contact angle for live-oil and water systems at reservoir conditions (high pressure, high temperature), and it presents a graphical (quantitative) method for determining asphaltene onset pressure (AOP) based on interfacial behavior. Water/oil IFT was measured at reservoir temperature using a pendant-drop-shape method for a system of live oils over a range of pressures above and below the AOP, which was already independently determined by means of particle-size-distribution and solid-detection-system techniques. The same pressure and temperature conditions were used to measure contact angle with quartz in the presence of deionized (DI) water as the surrounding medium. The temperature was controlled with an accuracy of ±0.1°C. Some measurements were performed twice to ensure the reproducibility of the experiments and methodology. This work presents the experimental study to quantify the change in interfacial behavior because of asphaltene precipitation and deposition. IFT/contact-angle measurements above and below AOP show that the interfacial behavior follows the normal trends above AOP as observed in other water/hydrocarbon systems. However, as evident when the pressure was reduced below the AOP, a relatively sharp change in the trend is observed in both the IFT and contact angle, which is caused by asphaltene migration to the interface in a way that acts as a natural surfactant. As asphaltenes precipitate and deposit in the mineral substrate, the surface turns less water-wet and the contact angle naturally increases to balance the equilibrium forces. This study sets a quantitative and alternative method to determine AOP, and presents new experimental data on IFT/contact angle of live-oil and water systems at reservoir conditions. Near the wellbore, asphaltene deposition can lead to pore plugging, where a large number of pore volumes flow through the productive life of the well. In this scenario, the size of aggregates (of asphaltene) is an important factor, especially when it is comparable with the pore size. On the other hand, deep in the reservoir, the effects of asphaltene precipitation and deposition on interfacial properties are more important because this can lead to wettability alteration. Thus, the results of this technique can be used to assess the potential impacts deep in the reservoir.

scholarly journals NaCl-related weathering of stone: the importance of kinetics and salt mixtures in environmental risk assessment

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Sebastiaan Godts ◽  
Scott Allan Orr ◽  
Julie Desarnaud ◽  
Michael Steiger ◽  
Katrin Wilhelm ◽  
...  
Keyword(s):  
Risk Assessment ◽  
Data Analysis ◽  
Salt Crystallization ◽  
Assessment Procedure ◽  
Climatic Data ◽  
Salt Weathering ◽  
Climate Data ◽  
Salt Mixture ◽  
Salt Mixtures ◽  
The Impact

AbstractSalt weathering is one of the most important causes of deterioration in the built environment. Two crucial aspects need further investigation to understand the processes and find suitable measures: the impact of different climatic environments and the properties of salt mixture crystallization. We demonstrate the importance of kinetics in quantifying crystallization and dissolution cycles by combining droplet and capillary laboratory experiments with climate data analysis. The results proved that dissolution times for pure NaCl are typically slower than crystallization, while thermodynamic modelling showed a lower RHeq of NaCl (65.5%) in a salt mixture (commonly found in the built heritage) compared to its RHeq as a single salt (75.5%). Following the results, a minimum time of 30 min is considered for dissolution and the two main RHeq thresholds could be applied to climate data analysis. The predicted number of dissolution/crystallization cycles was significantly dependent on the measurement frequency (or equivalent averaging period) of the climatic data. An analysis of corresponding rural and urban climate demonstrated the impact of spatial phenomena (such as the urban heat island) on the predicted frequency cycles. The findings are fundamental to improve appropriate timescale windows that can be applied to climate data and to illustrate a methodology to quantify salt crystallization cycles in realistic environments as a risk assessment procedure. The results are the basis for future work to improve the accuracy of salt risk assessment by including the kinetics of salt mixtures.

scholarly journals The Use and Impact of Cognitive Enhancers among University Students: A Systematic Review

2021 ◽  
Vol 11 (3) ◽  
pp. 355
Author(s):  
Safia Sharif ◽  
Amira Guirguis ◽  
Suzanne Fergus ◽  
Fabrizio Schifano
Keyword(s):  
Systematic Review ◽  
University Students ◽  
Early Stage ◽  
Cognitive Disorders ◽  
Neurological Complications ◽  
Cognitive Enhancers ◽  
Salt Mixtures ◽  
Meta Analyses ◽  
Medical Indications ◽  
The Impact

Introduction: Cognitive enhancers (CEs), also known as “smart drugs”, “study aids” or “nootropics” are a cause of concern. Recent research studies investigated the use of CEs being taken as study aids by university students. This manuscript provides an overview of popular CEs, focusing on a range of drugs/substances (e.g., prescription CEs including amphetamine salt mixtures, methylphenidate, modafinil and piracetam; and non-prescription CEs including caffeine, cobalamin (vitamin B12), guarana, pyridoxine (vitamin B6) and vinpocetine) that have emerged as being misused. The diverted non-prescription use of these molecules and the related potential for dependence and/or addiction is being reported. It has been demonstrated that healthy students (i.e., those without any diagnosed mental disorders) are increasingly using drugs such as methylphenidate, a mixture of dextroamphetamine/amphetamine, and modafinil, for the purpose of increasing their alertness, concentration or memory. Aim: To investigate the level of knowledge, perception and impact of the use of a range of CEs within Higher Education Institutions. Methodology: A systematic review was conducted in adherence with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Whilst 1400 studies were identified within this study through a variety of electronic databases (e.g., 520 through PubMed, 490 through Science Direct and 390 through Scopus), 48 papers were deemed relevant and were included in this review. Results: The most popular molecules identified here included the stimulant CEs, e.g., methylphenidate, modafinil, amphetamine salt mixtures and caffeine-related compounds; stimulant CEs’ intake was more prevalent among males than females; drugs were largely obtained from friends and family, as well as via the Internet. It is therefore suggested that CEs are increasingly being used among healthy individuals, mainly students without any diagnosed cognitive disorders, to increase their alertness, concentration, or memory, in the belief that these CEs will improve their performance during examinations or when studying. The impact of stimulant CEs may include tolerance, dependence and/or somatic (e.g., cardiovascular; neurological) complications. Discussion: The availability of CEs for non-medical indications in different countries is influenced by a range of factors including legal, social and ethical factors. Considering the risk factors and motivations that encourage university students to use CE drugs, it is essential to raise awareness about CE-related harms, counteract myths regarding “safe” CE use and address cognitive enhancement in an early stage during education as a preventative public health measure.

scholarly journals NaCl-Related Weathering of Stone: The Importance of Kinetics and Salt Mixtures in Environmental Risk Assessment

2020 ◽  
Author(s):  
Sebastiaan Godts ◽  
Scott Allan Orr ◽  
Julie Desarnaud ◽  
Michael Steiger ◽  
Katrin Wilhelm ◽  
...  
Keyword(s):  
Risk Assessment ◽  
Data Analysis ◽  
Salt Crystallization ◽  
Assessment Procedure ◽  
Climatic Data ◽  
Salt Weathering ◽  
Climate Data ◽  
Salt Mixture ◽  
Salt Mixtures ◽  
The Impact

Abstract Salt weathering is one of the most important causes of deterioration in the built environment. Two crucial aspects need further investigation to understand the processes and find suitable measures: the impact of different climatic environments and the properties of salt mixture crystallization. We demonstrate the importance of kinetics in quantifying crystallization and dissolution cycles by combining droplet and capillary laboratory experiments with climate data analysis. The results proved that dissolution times for pure NaCl were much slower than crystallization, while thermodynamic modelling showed a lower RHeq of NaCl (65.5%) in a salt mixture (commonly found in the built heritage) compared to its RHeq as a single salt (75.5%). Following the results, a minimum time of 0.5 hour is considered for dissolution and the two main RHeq thresholds could be applied to climate data analysis. The predicted number of dissolution/crystallization cycles was significantly dependent on the measurement frequency (or equivalent averaging period) of the climatic data. An analysis of corresponding rural and urban climate demonstrated the impact of spatial phenomena (such as the urban heat island) on the predicted frequency cycles. The findings are fundamental to improve appropriate timescale windows and to illustrate a methodology with specific points of interest to quantify salt crystallization cycles in realistic environments as a risk assessment procedure that can be applied to climate data. The results are the basis for future work to improve the accuracy of salt risk assessment by including the kinetics of salt mixtures. This will improve the understanding of past and future salt weathering mechanisms and enable scientifically informed conservation strategies.

scholarly journals Sphingomyelin Interfacial Behavior: The Impact of Changing Acyl Chain Composition

2000 ◽  
Vol 78 (4) ◽  
pp. 1921-1931 ◽  
Author(s):  
Xin-Min Li ◽  
Janice M. Smaby ◽  
Maureen M. Momsen ◽  
Howard L. Brockman ◽  
Rhoderick E. Brown
Keyword(s):  
Acyl Chain ◽  
Interfacial Behavior ◽  
Chain Composition ◽  
Acyl Chain Composition ◽  
The Impact

scholarly journals Assessment and Perspectives of Heat Transfer Fluids for CSP Applications

Energies ◽  
2021 ◽  
Vol 14 (22) ◽  
pp. 7486
Author(s):  
Alberto Giaconia ◽  
Anna Chiara Tizzoni ◽  
Salvatore Sau ◽  
Natale Corsaro ◽  
Emiliana Mansi ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Environmental Issues ◽  
Comparative Assessment ◽  
Medium Size ◽  
Concentrating Solar Power ◽  
Solar Salt ◽  
Heat Transfer Fluids ◽  
Salt Mixtures ◽  
Economic Perspectives ◽  
The Impact

Different fluid compositions have been considered as heat transfer fluids (HTF) for concentrating solar power (CSP) applications. In linear focusing CSP systems synthetic oils are prevalently employed; more recently, the use of molten salt mixtures in linear focusing CSP systems has been proposed too. This paper presents a comparative assessment of thermal oils and five four nitrate/nitrite mixtures, among the ones mostly employed or proposed so far for CSP applications. The typical medium-size CSP plant (50 MWe) operating with synthetic oil as HTF and the “solar salt” as TES was considered as a benchmark. In the first part of the paper, physical properties and operation ranges of different HTFs are reviewed; corrosion and environmental issues are highlighted too. Besides an extensive review of HTFs based on data available from the open literature, the authors report their own obtained experimental data needed to thoroughly compare different solutions. In the second part of the paper, the impact of the different HTF options on the design and operation of CSP plants are analyzed from techno-economic perspectives.

Formation of Lunar Craters and Bright Rays as a Result of Meteorite Impacts

1962 ◽  
Vol 14 ◽  
pp. 415-418
Author(s):  
K. P. Stanyukovich ◽  
V. A. Bronshten
Keyword(s):  
Explosive Charge ◽  
The Moon ◽  
Meteorite Impacts ◽  
The Earth ◽  
Lunar Craters ◽  
The Impact

The phenomena accompanying the impact of large meteorites on the surface of the Moon or of the Earth can be examined on the basis of the theory of explosive phenomena if we assume that, instead of an exploding meteorite moving inside the rock, we have an explosive charge (equivalent in energy), situated at a certain distance under the surface.

The Geosciences Applied to Lunar Exploration

1962 ◽  
Vol 14 ◽  
pp. 169-257 ◽  
Author(s):  
J. Green
Keyword(s):  
Lunar Surface ◽  
Probable Mechanism ◽  
Point Of View ◽  
Lunar Exploration ◽  
Geological Model ◽  
Apply Geophysics ◽  
Surface Features ◽  
The Impact

The term geo-sciences has been used here to include the disciplines geology, geophysics and geochemistry. However, in order to apply geophysics and geochemistry effectively one must begin with a geological model. Therefore, the science of geology should be used as the basis for lunar exploration. From an astronomical point of view, a lunar terrain heavily impacted with meteors appears the more reasonable; although from a geological standpoint, volcanism seems the more probable mechanism. A surface liberally marked with volcanic features has been advocated by such geologists as Bülow, Dana, Suess, von Wolff, Shaler, Spurr, and Kuno. In this paper, both the impact and volcanic hypotheses are considered in the application of the geo-sciences to manned lunar exploration. However, more emphasis is placed on the volcanic, or more correctly the defluidization, hypothesis to account for lunar surface features.

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