Coliform transport in a pristine reservoir: modeling and field studies

1998 ◽  
Vol 37 (2) ◽  
pp. 137-144 ◽  
Author(s):  
Elisa Garvey ◽  
John E. Tobiason ◽  
Michael Hayes ◽  
Evelyn Wolfram ◽  
David A. Reckhow ◽  
...  
Keyword(s):  
Model Development ◽  
Fate And Transport ◽  
Field Studies ◽  
Meteorological Conditions ◽  
Reservoir Modeling ◽  
Vertical Circulation ◽  
Quality Model ◽  
Circulation Patterns ◽  
In Situ Experiments

This paper reports on field studies and model development aimed at understanding coliform fate and transport in the Quabbin Reservoir, an oligotrophic drinking water supply reservoir. An investigation of reservoir currents suggested the importance of wind driven phenomena, and that both lateral and vertical circulation patterns exist. In-situ experiments of coliform decay suggested dependence on light intensity and yielded an appropriate decay coefficient to be used in CE-QUAL-W2, a two-dimensional hydrodynamic and water quality model. Modeling confirmed the sensitivity of reservoir outlet concentration to vertical variability within the reservoir, meteorological conditions, and location of coliform source.

An in situ and ex situ TEM study of the formation of thin cobalt silicide films by molecular beam epitaxy on the silicon (100) surface

1988 ◽  
Vol 46 ◽  
pp. 884-885
Author(s):  
D. Loretto ◽  
J. M. Gibson ◽  
S. M. Yalisove ◽  
R. T. Tung
Keyword(s):  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
Defect Density ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Ex Situ ◽  
Metal Base ◽  
In Situ Experiments ◽  
Potential Applications

The cobalt disilicide/silicon system has potential applications as a metal-base and as a permeable-base transistor. Although thin, low defect density, films of CoSi2 on Si(111) have been successfully grown, there are reasons to believe that Si(100)/CoSi2 may be better suited to the transmission of electrons at the silicon/silicide interface than Si(111)/CoSi2. A TEM study of the formation of CoSi2 on Si(100) is therefore being conducted. We have previously reported TEM observations on Si(111)/CoSi2 grown both in situ, in an ultra high vacuum (UHV) TEM and ex situ, in a conventional Molecular Beam Epitaxy system.The procedures used for the MBE growth have been described elsewhere. In situ experiments were performed in a JEOL 200CX electron microscope, extensively modified to give a vacuum of better than 10-9 T in the specimen region and the capacity to do in situ sample heating and deposition. Cobalt was deposited onto clean Si(100) samples by thermal evaporation from cobalt-coated Ta filaments.

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.

A computer-control program for TEM in situ fatigue experiments

1989 ◽  
Vol 47 ◽  
pp. 620-621
Author(s):  
Kenneth S. Vecchio ◽  
John A. Hunt
Keyword(s):  
Slow Crack Growth ◽  
Computer Control ◽  
Control Program ◽  
Video Tape ◽  
Computer Control System ◽  
Transmission Electron ◽  
In Situ Experiments ◽  
Tremendous Amount ◽  
And Control

In-situ experiments conducted within a transmission electron microscope provide the operator a unique opportunity to directly observe microstructural phenomena, such as phase transformations and dislocation-precipitate interactions, “as they happen”. However, in-situ experiments usually require a tremendous amount of experimental preparation beforehand, as well as, during the actual experiment. In most cases the researcher must operate and control several pieces of equipment simultaneously. For example, in in-situ deformation experiments, the researcher may have to not only operate the TEM, but also control the straining holder and possibly some recording system such as a video tape machine. When it comes to in-situ fatigue deformation, the experiments became even more complicated with having to control numerous loading cycles while following the slow crack growth. In this paper we will describe a new method for conducting in-situ fatigue experiments using a camputer-controlled tensile straining holder.The tensile straining holder used with computer-control system was manufactured by Philips for the Philips 300 series microscopes. It was necessary to modify the specimen stage area of this holder to work in the Philips 400 series microscopes because the distance between the optic axis and holder airlock is different than in the Philips 300 series microscopes. However, the program and interfacing can easily be modified to work with any goniometer type straining holder which uses a penrmanent magnet motor.

Interaction Process Model – ESM Quality Model Development Tool

2020 ◽  
Vol 25 (1) ◽  
pp. 10-17
Author(s):  
B.V. Boytsov ◽  
◽  
G.S. Zhetessova ◽  
M.K. Ibatov ◽  
◽  
...  
Keyword(s):  
Process Model ◽  
Swot Analysis ◽  
Statistical Data ◽  
Model Development ◽  
Interaction Process ◽  
Educational Process ◽  
Quality Model ◽  
Development Tool ◽  
The Republic ◽  
Education Science

The article discusses the methodology and provides the results of a multivariate SWOT analysis for a scientific and manufacturing educational process based on a set of regulatory and strategic documents, statistical data of the Republic of Kazakhstan; The main conclusions and description of the generated matrices for the subjects of interaction within the hierarchical triangle «Education – Science – Manufacturing (ESM)» are given.

Post-Hurricane Michael damage assessment using ADCIRC storm surge hindcast, image classification, and LiDAR

Shore & Beach ◽  
2019 ◽  
pp. 3-14 ◽  
Author(s):  
Joshua Davis ◽  
Diana Mitsova ◽  
Tynon Briggs ◽  
Tiffany Briggs
Keyword(s):  
Wave Energy ◽  
Field Studies ◽  
Feedback Mechanism ◽  
Water Velocity ◽  
Airborne Lidar ◽  
Storm Events ◽  
Magnetic Current ◽  
Coastal Mapping ◽  
Electro Magnetic

Wave forcing from hurricanes, nor’easters, and energetic storms can cause erosion of the berm and beach face resulting in increased vulnerability of dunes and coastal infrastructure. LIDAR or other surveying techniques have quantified post-event morphology, but there is a lack of in situ hydrodynamic and morphodynamic measurements during extreme storm events. Two field studies were conducted in March 2018 and April 2019 at Bethany Beach, Delaware, where in situ hydrodynamic and morphodynamic measurements were made during a nor’easter (Nor’easter Riley) and an energetic storm (Easter Eve Storm). An array of sensors to measure water velocity, water depth, water elevation and bed elevation were mounted to scaffold pipes and deployed in a single cross-shore transect. Water velocity was measured using an electro-magnetic current meter while water and bed elevations were measured using an acoustic distance meter along with an algorithm to differentiate between the water and bed during swash processes. GPS profiles of the beach face were measured during every day-time low tide throughout the storm events. Both accretion and erosion were measured at different cross-shore positions and at different times during the storm events. Morphodynamic change along the back-beach was found to be related to berm erosion, suggesting an important morphologic feedback mechanism. Accumulated wave energy and wave energy flux per unit area between Nor’easter Riley and a recent mid-Atlantic hurricane (Hurricane Dorian) were calculated and compared. Coastal Observations: JALBTCX/NCMP emergency-response airborne Lidar coastal mapping & quick response data products for 2016/2017/2018 hurricane impact assessments

Real-life Field Studies of the NOx Removing Properties of Photocatalytic Surfaces in Roskilde and Copenhagen Airport, Denmark

2020 ◽  
Vol 01 ◽  
Author(s):  
Henrik Jensen ◽  
Pernille D. Pedersen
Keyword(s):  
Air Quality ◽  
High Stability ◽  
Reference Site ◽  
Real Life ◽  
Field Studies ◽  
The Real ◽  
Before And After ◽  
Parking Lot ◽  
Photocatalytic Concrete

Aims: To evaluate the real-life effect of photocatalytic surfaces on the air quality at two test-sites in Denmark. Background: Poor air quality is today one of the largest environmental issues, due to the adverse effects on human health associated with high levels of air pollution, including respiratory issues, cardiovascular disease (CVD), and lung cancer. NOx removal by TiO2 based photocatalysis is a tool to improve air quality locally in areas where people are exposed. Methods: Two test sites were constructed in Roskilde and Copenhage airport. In Roskilde, the existing asphalt at two parking lots was treated with TiO2 containing liquid and an in-situ ISO 22197-1 test setup was developed to enable in-situ evaluation of the activity of the asphalt. In CPH airport, photocatalytic concrete tiles were installed at the "kiss and fly" parking lot, and NOx levels were continuously monitored in 0.5 m by CLD at the active site and a comparable reference site before and after installation for a period of 2 years. Results: The Roskilde showed high stability of the photocatalytic coating with the activity being largely unchanged over a period of 2 years. The CPH airport study showed that the average NOx levels were decreased by 12 % comparing the before and after NOx concentrations at the active and reference site. Conclusion: The joined results of the two Danish demonstration projects illustrate a high stability of the photocatalytic coating as well as a high potential for improvements of the real-life air quality in polluted areas.

scholarly journals Upscaling THM modeling from small-scale to full-scale in-situ experiments in the Callovo-Oxfordian claystone

2021 ◽  
Vol 144 ◽  
pp. 104582
Author(s):  
D.M. Seyedi ◽  
C. Plúa ◽  
M. Vitel ◽  
G. Armand ◽  
J. Rutqvist ◽  
...  
Keyword(s):  
Full Scale ◽  
Small Scale ◽  
In Situ Experiments

scholarly journals Memory Effect on a LDH/zeolite A Composite: An XRD In Situ Study

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2102
Author(s):  
Breno G. P. Bezerra ◽  
Lindiane Bieseki ◽  
Mariele I. S. de Mello ◽  
Djalma R. da Silva ◽  
Cristiane B. Rodella ◽  
...  
Keyword(s):  
Memory Effect ◽  
Inert Atmosphere ◽  
Effect Study ◽  
Physical Mixture ◽  
Zeolite A ◽  
Three Samples ◽  
In Situ Experiments ◽  
Double Hydroxide ◽  
Rehydration Process

In this memory effect study, hydrotalcite-type compounds in the lamellar double hydroxide-like (LDH)/zeolite A composite material were analyzed using X-Ray Diffration XRD) in situ experiments. Three samples were analyzed: Al,Mg-LDH, Al,Mg-LDH/ZA composite, and a physical mixture (50/50 wt%) of zeolite A and Al,Mg-LDH. The Al,Mg-LDH sample was treated at 500 °C in an O2 atmosphere and subsequently rehydrated. The Al,Mg-LDH/ZA composites had three treatments: one was performed at 300 °C in a He atmosphere, and two treatments were performed with an O2 atmosphere at 300 and 500 °C. In the physical mixture, two treatments were carried out under O2 flow at 500 °C and under He flow at 300 °C. Both went through the rehydration process. All samples were also analyzed by energy dispersive spectroscopy (EDS) and scanning electron microscopy (SEM). The results show that the LDH phase in the Al,Mg-LDH/ZA compounds has memory effects, and thus, the compound can be calcined and rehydrated. For the LDH in the composite, the best heat treatment system is a temperature of 300 °C in an inert atmosphere.

scholarly journals Advanced experimental approaches to marine water-column biogeochemical processes

2017 ◽  
Vol 75 (1) ◽  
pp. 30-42 ◽  
Author(s):  
Louis Legendre ◽  
Richard B Rivkin ◽  
Nianzhi Jiao
Keyword(s):  
Water Column ◽  
Numerical Models ◽  
Free Water ◽  
Sea Surface ◽  
Biogeochemical Processes ◽  
In Situ Experiments ◽  
Technological Developments ◽  
Approaches To Study ◽  
Experimental Approaches

Abstract This “Food for Thought” article examines the potential uses of several novel scientific and technological developments, which are currently available or being developed, to significantly advance or supplement existing experimental approaches to study water-column biogeochemical processes (WCB-processes). After examining the complementary roles of observation, experiments and numerical models to study WCB-processes, we focus on the main experimental approaches of free-water in situ experiments, and at-sea and on-land meso- and macrocosms. We identify some of the incompletely resolved aspects of marine WCB-processes, and explore advanced experimental approaches that could be used to reduce their uncertainties. We examine three such approaches: free-water experiments of lengthened duration using bioArgo floats and gliders, at-sea mesocosms deployed several 100s m below the sea-surface using new biogeochemical sensors, and 50 m-tall on-land macrocosms. These approaches could lead to significant progress in concepts related to marine WCB-processes.

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