Deepwater Cathodic Protection: Part 1—Laboratory Simulation Experiments

CORROSION ◽  
2002 ◽  
Vol 58 (1) ◽  
pp. 38-48 ◽  
Author(s):  
S. Chen ◽  
W. H. Hartt
Keyword(s):  
Cathodic Protection ◽  
Laboratory Simulation ◽  
Simulation Experiments

An Array of Multielectrodes for Locating, Visualizing, and Quantifying Stray Current Corrosion

CORROSION ◽  
10.5006/2828 ◽  
2018 ◽  
Vol 74 (10) ◽  
pp. 1093-1101 ◽  
Author(s):  
Ke Wang ◽  
Facundo Bob Varela ◽  
Mike Yongjun Tan
Keyword(s):  
Cathodic Protection ◽  
Laboratory Simulation ◽  
Buried Pipeline ◽  
Stray Current ◽  
Simulation Experiments ◽  
Corrosion Rates ◽  
Pipeline Corrosion ◽  
Probe Array

An array of multielectrode corrosion probes, designed based on a series of coupled wire beam electrodes (WBEs), has been devised as a new tool for locating, visualizing, and quantifying the effects of stray currents on buried pipeline corrosion. It has been demonstrated in laboratory simulation experiments that this WBE probe array is capable of detecting stray current corrosion affected sites along a pipeline, visualizing stray current corrosion patterns and corrosion rates, and evaluating the efficiency of cathodic protection against stray current corrosion. Based on these results, two applications of this WBE probe array have been proposed for stray current corrosion survey and monitoring.

scholarly journals Untangling the formation and liberation of water in the lunar regolith

2019 ◽  
Vol 116 (23) ◽  
pp. 11165-11170 ◽  
Author(s):  
Cheng Zhu ◽  
Parker B. Crandall ◽  
Jeffrey J. Gillis-Davis ◽  
Hope A. Ishii ◽  
John P. Bradley ◽  
...  
Keyword(s):  
Solar Wind ◽  
Hydroxyl Radicals ◽  
Laboratory Experiments ◽  
Synergistic Effects ◽  
Lunar Regolith ◽  
Laboratory Simulation ◽  
The Moon ◽  
Imaging Studies ◽  
Simulation Experiments ◽  
Proton Implantation

The source of water (H2O) and hydroxyl radicals (OH), identified on the lunar surface, represents a fundamental, unsolved puzzle. The interaction of solar-wind protons with silicates and oxides has been proposed as a key mechanism, but laboratory experiments yield conflicting results that suggest that proton implantation alone is insufficient to generate and liberate water. Here, we demonstrate in laboratory simulation experiments combined with imaging studies that water can be efficiently generated and released through rapid energetic heating like micrometeorite impacts into anhydrous silicates implanted with solar-wind protons. These synergistic effects of solar-wind protons and micrometeorites liberate water at mineral temperatures from 10 to 300 K via vesicles, thus providing evidence of a key mechanism to synthesize water in silicates and advancing our understanding on the origin of water as detected on the Moon and other airless bodies in our solar system such as Mercury and asteroids.

scholarly journals Origin of alkylphosphonic acids in the interstellar medium

2019 ◽  
Vol 5 (8) ◽  
pp. eaaw4307 ◽  
Author(s):  
Andrew M. Turner ◽  
Matthew J. Abplanalp ◽  
Alexandre Bergantini ◽  
Robert Frigge ◽  
Cheng Zhu ◽  
...  
Keyword(s):  
Cosmic Rays ◽  
Organic Phosphorus ◽  
Galactic Cosmic Rays ◽  
Laboratory Simulation ◽  
Facile Synthesis ◽  
Simulation Experiments ◽  
Murchison Meteorite ◽  
Phosphorus Containing ◽  
Initial Source ◽  
Alkylphosphonic Acids

For decades, the source of phosphorus incorporated into Earth’s first organisms has remained a fundamental, unsolved puzzle. Although contemporary biomolecules incorporate P(+V) in their phosphate moieties, the limited bioavailability of phosphates led to the proposal that more soluble P(+III) compounds served as the initial source of phosphorus. Here, we report via laboratory simulation experiments that the three simplest alkylphosphonic acids, soluble organic phosphorus P(+III) compounds, can be efficiently generated in interstellar, phosphine-doped ices through interaction with galactic cosmic rays. This discovery opens a previously overlooked avenue into the formation of key molecules of astrobiological significance and untangles basic mechanisms of a facile synthesis of phosphorus-containing organics in extraterrestrial ices, which can be incorporated into comets and asteroids before their delivery and detection on Earth such as in the Murchison meteorite.

Magnetospheric Effects as a New Aspect of the Asteroid Impact Problem: Necessity and Possibilities of Laboratory Simulation Experiments

1997 ◽  
Vol 822 (1 Near-Earth Ob) ◽  
pp. 583-584 ◽  
Author(s):  
YURI P. ZAKHAROV ◽  
SERGEI A. NIKITIN ◽  
ARNOLD G. PONOMARENKO ◽  
SHIGEYUKI MINAMI
Keyword(s):  
Laboratory Simulation ◽  
Simulation Experiments ◽  
Asteroid Impact ◽  
Impact Problem

scholarly journals Double Layers in Plasmas

1987 ◽  
Vol 5 (2) ◽  
pp. 167-168 ◽  
Author(s):  
Alton C. Williams ◽  
Heinrich Hora
Keyword(s):  
Time Dependent ◽  
Laboratory Simulation ◽  
Double Layers ◽  
Space Plasmas ◽  
Simulation Experiments ◽  
Electric Double Layers

The phenomenon of electric double layers in plasmas as a generalization of ambipolar effects and as an essential time dependent and oscillating phenomenon in the plasma interior, has emerged from studies in laser produced plasmas as well as from similar problems in space plasmas and their laboratory simulation experiments. While these results have been published occasionally in various places including the most prestigious journals and in small topical conferences, there was still a need to enter a more comprehensive presentation and overview into a referred journal.

scholarly journals Alteration of Fractionation and Bioavailability of Arsenic (As) in Paddy Soil under Transition from Aerobic to Anaerobic Conditions

2021 ◽  
Vol 20 (1) ◽  
pp. 1-7
Author(s):  
Apichaya Duangthong ◽  
◽  
Seelawut Damrongsiri ◽  
Keyword(s):  
Organic Compounds ◽  
Laboratory Simulation ◽  
Soil Conditions ◽  
Tetraacetic Acid ◽  
Anaerobic Conditions ◽  
Simulation Experiments ◽  
Long Period ◽  
Mobile Fraction ◽  
The Impact ◽  
Anaerobic Environment

The impact of the change from aerobic to anaerobic immersed soil conditions on arsenic (As) fractionation (Tessier’s method) and its bioavailability (ethylene diamine tetraacetic acid extractable) were assessed. As-contaminated paddy soils were tested by laboratory simulation experiments. The samples were aerobic, with 35-49 mg/kg of As at low bioavailability (<2%). Most As was distributed in the stable fraction (77%), followed by As bound to ferric and manganese oxide (17%) and organic compounds (5%), while the mobile fraction (exchangeable and mildly acid-soluble) was limited (1%). After one month under anaerobic simulation, redox potential reduced to less than zero (-32 to -124 mV). The stable fraction of As decreased (-17%), while the mobile fraction increased (+16%) and As bioavailability also increased (+26% total As). Increase in the As mobile fraction was associated with freshly precipitated compounds. The As content in the soil altered from a stable fraction to an available fraction when confined in an anaerobic environment for a long period. Results indicated that agricultural methods which promoted anaerobic conditions in As-contaminated soil should be avoided.

scholarly journals Laboratory Simulation of Cometary Structures

1989 ◽  
Vol 116 (1) ◽  
pp. 299-311
Author(s):  
KH.I. Ibadinov ◽  
A.A. Rahmonov ◽  
A.SH. Bjasso
Keyword(s):  
Thermal Conductivity ◽  
Surface Albedo ◽  
Cometary Nucleus ◽  
Gas Production ◽  
Laboratory Simulation ◽  
Dust Production ◽  
Simulation Experiments ◽  
Order Of Magnitude ◽  
Vega 1 ◽  
Volatile Impurities

AbstractThe properties of a porous mineral crust on the surface of an icy cometary nucleus and the crust's influence on the thermal regime and gas production in the nucleus have been studied by laboratory simulation experiments. A nucleus model of H2O ice with the impurity of graphite particles has been shown to display the same temperature and surface albedo as those determined for Comet Halley’s nucleus by the VEGA 1, VEGA 2, and Giotto spacecraft. The effective thermal conductivity of a crust with a density of 0.5 × 102 kg m−3 to 0.7 × 102 kg m−3 is less than 10−1 W m−1 K−1, while the crust’s strength (103 to 104 Pa) is not sufficient to withstand its erosion by the sublimating gases. A crust that is 1 cm thick lowers the gas production of the nucleus model by one order of magnitude. The destruction of the crust, and the gas and dust production of Comet Halley’s nucleus can be explained either by a spotty surface on the nucleus or, more likely, by the presence of volatile impurities such as CO2 with concentrations of 1 × 10−2 to 3 × 10−2 in the H2O ice under the crust.

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