Preliminary studies on the impact of in situ oil sand extraction methods on the movement of water soluble organics and inorganics by a pilot scale test

2018 ◽  
Vol 4 (8) ◽  
pp. 1124-1132
Author(s):  
Xiaomeng Wang ◽  
Kim Kasperski ◽  
Amanda Cook ◽  
Adrian Ilko
Keyword(s):  
Elevated Temperatures ◽  
Extraction Methods ◽  
Pilot Scale ◽  
Water Soluble ◽  
Oil Sand ◽  
Thermal Operation ◽  
Scale Test ◽  
The Impact ◽  
Sand Extraction

Pilot scale tests on the impact of the elevated temperatures and pressures of in situ thermal operation on groundwater chemistry.

Pilot-scale injection of colloidal activated carbon for PFAS immobilization at a contaminated field site

2020 ◽  
Author(s):  
Fritjof Fagerlund ◽  
Georgios Niarchos ◽  
Lutz Ahrens ◽  
Dan Berggren Kleja ◽  
Jonny Bergman ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Seasonal Changes ◽  
Preferential Flow ◽  
Pilot Scale ◽  
Contaminated Site ◽  
Flow Paths ◽  
Groundwater Levels ◽  
Geological Setting ◽  
Scale Test

<p>Per- and polyfluorinated alkyl substances (PFASs) are extremely recalcitrant contaminants that pose a challenge for remediation in soil and groundwater due to their chemical stability and resistance to degradation. They are used in numerous consumer products and their use in firefighting aqueous-film-forming foams has led to worldwide contamination of groundwater resources associated with airports and firefighting training areas. One of the currently most promising in-situ treatment techniques is stabilization using activated carbon (AC) sorbents that can immobilize PFASs in the soil and prevent further spreading from a contaminated site. However, few documented field studies exist.</p><p>In this study we investigated in-situ stabilization of PFASs by injection of colloidal activated carbon (CAC, PlumeStop®) at a PFAS contaminated site in Arboga, Sweden. Prior to the design of the pilot-scale test and CAC injection, the geology and state of contamination were carefully characterized and PFAS concentrations and groundwater levels were monitored continuously for almost one year. CAC was injected to create a defined zone of PFAS-sorption where PFASs from the contaminant plume would be sorbed to CAC and removed from the flowing groundwater, similar to a permeable reactive barrier. The effect of the injected CAC was studied by monitoring PFAS concentrations in the groundwater up- and down-gradient as well as within the CAC barrier both before and after injection. General water chemistry and groundwater levels were also monitored.</p><p>The site characterization showed that there are two distinct source zones of PFAS contamination with different contamination signatures. Continuous baseline monitoring prior to CAC injection did not show any major changes in PFAS concentrations, but revealed seasonal variations in the groundwater levels and flow patterns, leading to seasonal changes also in the direction of contaminant transport. The CAC injection pilot-scale test was therefore designed to shield the down-gradient evaluation wells in small part of the plume accounting for seasonal changes. The geological setting of the site mainly is clayey till soil of relatively low hydraulic conductivity on top of crystalline bedrock, but there are also high permeability flow paths. The low-pressure CAC injections were hence designed and adapted to avoid excessive preferential flow of CAC and achieve a good distribution of CAC in the intended treatment zone (barrier).</p><p>Preliminary results from the monitoring showed strong reduction of all measured PFASs within and directly down-gradient of the CAC barrier. These results indicate that the installation of the CAC barrier was successful despite a relatively complex geological setting where fast preferential flow paths exist. The continuing monitoring will show how the CAC performs over time.</p>

scholarly journals Direct Observation via In Situ Heated Stage EBSD Analysis of Recrystallization of Phosphorous Deoxidised Copper in Unstrained and Strained Conditions

2019 ◽  
Vol 26 (7) ◽  
pp. 1030-1035 ◽  
Author(s):  
S. Taylor ◽  
I. Masters ◽  
Z. Li ◽  
H. R. Kotadia
Keyword(s):  
Elevated Temperatures ◽  
Inverse Pole Figure ◽  
Grain Structure ◽  
Ebsd Analysis ◽  
Recrystallization Temperature ◽  
Heating Rates ◽  
Material Condition ◽  
The Impact ◽  
Heated Stage

Abstract Recrystallization of phosphorous deoxidised copper used for strength critical applications at elevated temperatures was investigated by means of in situ heated stage EBSD analysis using a Gatan Murano heated stage mounted within a Carl Zeiss Sigma FEGSEM electron microscope. The influence of applied strain as the result of deformation within a Nakajima test as an analogue for industrial forming on the recrystallization temperature was investigated, the impact of increased heating rates on microstructural evolution was also investigated. Inverse pole figure plots combined with regions of reduction in local misorientations and variations in geometrically necessary dislocations were used to establish the point of recrystallization and the recrystallized fraction of the material. Recrystallization was observed to occur at temperatures as low as 130 °C in highly strained samples compared to around 300 °C within the annealed samples dependent upon heating rate. Increased heating rates were observed to produce a finer final grain structure but had little effect on presence of <111> 60° grain twins, which was influenced more by initial material condition. Graphic Abstract

scholarly journals Self-emulsifying therapeutic system: a potential approach for delivery of lipophilic drugs

2011 ◽  
Vol 47 (3) ◽  
pp. 447-465 ◽  
Author(s):  
Jyoti Wadhwa ◽  
Anroop Nair ◽  
Rachna Kumria
Keyword(s):  
Drug Disposition ◽  
Water Soluble ◽  
Therapeutic System ◽  
System A ◽  
Gastrointestinal Fluid ◽  
Water Soluble Drugs ◽  
Poorly Water Soluble ◽  
The Impact

Self-emulsifying therapeutic system (SETs) provide an effective and intelligent solution to the various issues related to the formulation of hydrophobic drugs with limited solubility in gastrointestinal fluid. Although the potential utility of SETs is well known, only in recent years has a mechanistic understanding of the impact of these systems on drug disposition emerged. These in situ emulsion-forming systems have a high stability when incorporated in various dosage forms. SETs are being looked upon as systems which can overcome the problems associated with delivery of poorly water soluble drugs. An in-depth knowledge about lipids and surfactants that can contribute to these systems, criterion for their selection and the proportion in which they can be used, represent some crucial factors determining the in vivo performance of these systems. This article presents a comprehensive account of various types of self-emulsifying formulations with emphasis on their composition and examples of currently marketed preparations.

Electron and ion irradiation-induced dissolution of mechanical twins in the intermetalic U3Si: An in situ HVEM study

1989 ◽  
Vol 47 ◽  
pp. 652-653
Author(s):  
Charles W. Allen ◽  
Robert C. Birtcher
Keyword(s):  
Elevated Temperatures ◽  
Ion Irradiation ◽  
Ion Beam ◽  
National Laboratory ◽  
Argonne National Laboratory ◽  
Heavy Ion ◽  
High Energy ◽  
Mechanical Twinning ◽  
In Situ Experiments

The uranium silicides, including U3Si, are under study as candidate low enrichment nuclear fuels. Ion beam simulations of the in-reactor behavior of such materials are performed because a similar damage structure can be produced in hours by energetic heavy ions which requires years in actual reactor tests. This contribution treats one aspect of the microstructural behavior of U3Si under high energy electron irradiation and low dose energetic heavy ion irradiation and is based on in situ experiments, performed at the HVEM-Tandem User Facility at Argonne National Laboratory. This Facility interfaces a 2 MV Tandem ion accelerator and a 0.6 MV ion implanter to a 1.2 MeV AEI high voltage electron microscope, which allows a wide variety of in situ ion beam experiments to be performed with simultaneous irradiation and electron microscopy or diffraction.At elevated temperatures, U3Si exhibits the ordered AuCu3 structure. On cooling below 1058 K, the intermetallic transforms, evidently martensitically, to a body-centered tetragonal structure (alternatively, the structure may be described as face-centered tetragonal, which would be fcc except for a 1 pet tetragonal distortion). Mechanical twinning accompanies the transformation; however, diferences between electron diffraction patterns from twinned and non-twinned martensite plates could not be distinguished.

The threshold energy for atom displacement in fcc metals

1990 ◽  
Vol 48 (4) ◽  
pp. 530-531
Author(s):  
Wilfried Sigle ◽  
Matthias Hohenstein ◽  
Alfred Seeger
Keyword(s):  
Growth Rate ◽  
Elevated Temperatures ◽  
Threshold Energy ◽  
Dislocation Loops ◽  
Absolute Minimum ◽  
Voltage Electron ◽  
Atom Displacement ◽  
Electron Microscopes ◽  
Fcc Metal

Prolonged electron irradiation of metals at elevated temperatures usually leads to the formation of large interstitial-type dislocation loops. The growth rate of the loops is proportional to the total cross-section for atom displacement,which is implicitly connected with the threshold energy for atom displacement, Ed . Thus, by measuring the growth rate as a function of the electron energy and the orientation of the specimen with respect to the electron beam, the anisotropy of Ed can be determined rather precisely. We have performed such experiments in situ in high-voltage electron microscopes on Ag and Au at 473K as a function of the orientation and on Au as a function of temperature at several fixed orientations.Whereas in Ag minima of Ed are found close to <100>,<110>, and <210> (13-18eV), (Fig.1) atom displacement in Au requires least energy along <100>(15-19eV) (Fig.2). Au is thus the first fcc metal in which the absolute minimum of the threshold energy has been established not to lie in or close to the <110> direction.

Genetic Variation: Impact on Folate (and Choline) Bioefficacy

2010 ◽  
Vol 80 (45) ◽  
pp. 319-329 ◽  
Author(s):  
Allyson A. West ◽  
Marie A. Caudill
Keyword(s):  
Carbon Metabolism ◽  
Genetic Variants ◽  
Plasma Homocysteine ◽  
Water Soluble ◽  
Gene Interactions ◽  
Dietary Folate ◽  
Methyl Donors ◽  
Common Genetic Variants ◽  
One Carbon Metabolism ◽  
The Impact

Folate and choline are water-soluble micronutrients that serve as methyl donors in the conversion of homocysteine to methionine. Inadequacy of these nutrients can disturb one-carbon metabolism as evidenced by alterations in circulating folate and/or plasma homocysteine. Among common genetic variants that reside in genes regulating folate absorptive and metabolic processes, homozygosity for the MTHFR 677C > T variant has consistently been shown to have robust effects on status markers. This paper will review the impact of genetic variants in folate-metabolizing genes on folate and choline bioefficacy. Nutrient-gene and gene-gene interactions will be considered along with the need to account for these genetic variants when updating dietary folate and choline recommendations.

Functional Poly(p-Xylylene)s via Chemical Reduction of Poly(p-Phenylene Vinylene)s

2019 ◽  
Author(s):  
Ain Uddin ◽  
Weifan Sang ◽  
Yong Gao ◽  
Kyle Plunkett
Keyword(s):  
Film Formation ◽  
Chemical Reduction ◽  
Water Soluble ◽  
Phenylene Vinylene ◽  
Polymer Modification ◽  
Polymer Backbone ◽  
Crosslinking Process ◽  
Conducting Membranes ◽  
In Situ Crosslinking

The synthesis of poly(p-xylylene)s (PPXs) with sidechains containing alkyl bromide functionality, and their post-polymer modification, is described. The PPXs were prepared by a diimide hydrogenation of poly(p-phenylene vinylene)s (PPVs) that were originally synthesized by a Gilch polymerization. The polymer backbone reduction was carried out with hydrazine hydrate in toluene at 80 °C to provide polymers with the sidechain-containing bromide functionality intact. To demonstrate post-polymer modification of the sidechains, the resulting PPX polymers were modified with trimethylamine to form tetraalkylammonium ion functionality and were evaluated as anion conducting membranes. While PPX homopolymers containing tetralkylammonium ions were completely water soluble and not able to form valuable films, PPX copolymers containing mixed tetraalkylammonium ions and hydrophobic chains were capable of film formation and alkaline stability. In addition, an in situ crosslinking process that used N,N,N',N'-tetramethyl-1,6-hexanediamine during the tetraalkylammonium formation of brominated PPX polymers was also evaluated and gave reasonable films with conductivities of ~10 mS-cm-1.

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