Quantifying the volume increase and chemical exchange during serpentinization

Geology ◽  
2020 ◽  
Vol 48 (6) ◽  
pp. 552-556 ◽  
Author(s):  
Frieder Klein ◽  
Véronique Le Roux
Keyword(s):  
Volume Expansion ◽  
Laboratory Experiments ◽  
Chemical Exchange ◽  
Three Dimensional ◽  
Fluid Composition ◽  
Volume Changes ◽  
Volume Increase ◽  
Increasing Process ◽  
Static Conditions ◽  
Measured Volume

Abstract Quantifying the concurrent changes in rock volume and fluid composition during serpentinization remains a major challenge in assessing its physicochemical effects during continental rifting, seafloor spreading, and subduction. Here we conducted a series of 11 hydrothermal laboratory experiments where cylindrical cores of natural dunite, harzburgite, and pyroxenite were reacted with an aqueous solution at 300 °C and 35 MPa for up to 18 months. Using three-dimensional microcomputed tomography and thermogravimetry, we show that rock volume systematically increased with time and extent of reaction, leading to a volume increase of 44% (±8%) in altered rock domains after 10–18 months of serpentinization. The volume expansion was accompanied by Mg-Ca exchange between fluid and rock, while Fe and Si were largely conserved. We find that the protolith composition (olivine/orthopyroxene ratio) plays a significant role in controlling the fluid chemistry and the proportions of hydrous secondary minerals during serpentinization. Agreement between alteration mineralogy, composition of reacting fluids, and measured volume changes suggests that serpentinization under static conditions is a volume-increasing process in spite of demonstrable mass transfer. Volume expansion implies an increased water carrying capacity and buoyancy force of serpentinite per unit mass of protolith, while Mg-Ca exchange during serpentinization may affect the Mg/Ca ratio of seawater on Earth and possibly other ocean worlds.

Migration-associated volume changes in neutrophils facilitate the migratory process in vitro

1994 ◽  
Vol 267 (6) ◽  
pp. C1623-C1632 ◽  
Author(s):  
S. Rosengren ◽  
P. M. Henson ◽  
G. S. Worthen
Keyword(s):  
Neutrophil Migration ◽  
Three Dimensional ◽  
Cell Swelling ◽  
Neutrophil Granulocytes ◽  
Collagen Gels ◽  
Volume Changes ◽  
Volume Increase ◽  
Significant Volume ◽  
Volume Measurements

Neutrophil granulocytes, while migrating, undergo substantial shape changes from the round, resting state to a polarized phenotype. In the present study, we monitored cell volume changes in neutrophils migrating toward the chemotactic agent N-formyl-methionyl-leucyl-phenylalanine (FMLP) in collagen gels. Neutrophil volume was measured through optical sectioning on a confocal microscope and three-dimensional reconstruction. This method correlated well with Coulter counter volume measurements. Migrating neutrophils displayed a significant volume increase of 35-60%. The cell swelling appeared to depend on sodium/proton antiport activity because it was abrogated by amiloride and dimethyl-amiloride, inhibitors of the antiport, and by substitution of sodium in the buffers by choline, which is not transported by the antiport. Neutrophils exposed to FMLP gradients through impenetrable filters also displayed significant volume changes, whereas cells placed on similar filters in homogeneous concentrations of FMLP did not. This supports the notion of a differential volume response depending on the mode of presentation of the chemotactic agent. The role of volume increase in facilitating neutrophil migration was adduced by two lines of evidence: 1) hyposmolar swelling enhanced and hyperosmolar shrinking decreased neutrophil migration toward FMLP in Boyden chambers and 2) sodium/proton antiport inhibitors decreased neutrophil migration; however, this was reversed in hyposmolar buffers, which induced a volume increase similar to that seen in normal migrating cells. The migration-associated volume increase may be a crucial event for the ability of neutrophils to function as the first line of defense at sites of infection.

Three-dimensional numerical simulation of the nitriding process

2004 ◽  
Vol 120 ◽  
pp. 777-783
Author(s):  
P. Duranton ◽  
J. Devaux ◽  
M. Larreur ◽  
R. Fortunier ◽  
J.-M. Bergheau
Keyword(s):  
Numerical Simulation ◽  
Volume Expansion ◽  
Gear Tooth ◽  
Three Dimensional ◽  
Mechanical Analysis ◽  
Nitriding Process ◽  
Chromium Nitride ◽  
Elastic Behaviour ◽  
Volume Changes ◽  
Precipitation Analysis

This paper presents a three-dimensional numerical simulation of a nitriding process applied to an industrial component. The aim of the simulation is to predict the residual stresses and distortions due to volume changes induced by chromium nitride (CrN) and carbides (M23C6 et M4C3) formation. The simulation is performed in two steps. The diffusion of nitrogen and the precipitation of chrome nitride and carbides are first simulated. Then stresses and strains are calculated, assuming an elastic behaviour of the component, and using a volume expansion due to the precipitate concentration. The proposed approach is applied on a gear tooth. Small holes and details were neglected. For symmetry reasons, only half a tooth is taken into account. As the main phenomena take place through the first millimetre from the outer surface, a special attention was paid on meshing. The mesh used for the diffusion and precipitation analysis is composed of 1 130 000 nodes and 1 110 000 elements. For the mechanical analysis, a coarser mesh including only 165 000 nodes and 290 000 elements was used.

Bottom End-Closure Design Optimization of DOT-39 Non-Refillable Refrigerant Cylinders

2005 ◽  
Vol 127 (2) ◽  
pp. 112-118 ◽  
Author(s):  
Y. Kisioglu ◽  
J. R. Brevick ◽  
G. L. Kinzel
Keyword(s):  
Finite Element Analysis ◽  
Volume Expansion ◽  
Three Dimensional ◽  
Experimental Tests ◽  
Experimental Investigations ◽  
Element Analysis ◽  
Numerical Investigations ◽  
Pressure Tests ◽  
Experiment Technique ◽  
Static Conditions

This study addresses the problem of stability (standing of cylinders upright) of DOT-39 nonrefillable refrigerant cylinders using both experimental and finite element analysis (FEA) approaches. When these cylinders are designed using traditional methods they often suffer permanent volume expansion at the bottom end closure and become unstable when they are pressure tested experimentally. In this study, experimental investigations were carried out using hydrostatic pressure tests with water. In the case of numerical investigations, FEA models were developed for three-dimensional (3D) axisymmetric quasi-static conditions. The FEA models were constructed using nonhomogenous material nonlinearity and geometrical nonuniformity conditions. The results obtained from both FEA models and experimental tests were compared. To eliminate the instability of these cylinders, a design of experiment technique was employed to optimize the bottom end-closure design using the FEA models.

The Petrogenetic Model, an Extension of Bowen's Petrogenetic Grid

1962 ◽  
Vol 99 (6) ◽  
pp. 558-569 ◽  
Author(s):  
Peter J. Wyllie
Keyword(s):  
Experimental Data ◽  
Constant Pressure ◽  
Three Dimensional ◽  
Pore Fluid ◽  
Fluid Composition ◽  
Solid Reaction ◽  
Petrogenetic Model ◽  
Wide Range ◽  
Opposite Face ◽  
Reaction Surfaces

AbstractBowen's petrogenetic grid is a PT projection containing univariant curves for decarbonation, dehydration, and solid-solid reactions, with vapour pressure (Pf) equal to total pressure (Ps). Analysis of experimental data in the system MgO–CO2–H2O leads to an expansion of this grid. Three of the important variables in metamorphism when Pf = Ps are P, T, and variation of the pore fluid composition between H2O and CO2. These can be illustrated in a three-dimensional petrogenetic model; one face is a PT plane for reactions occurring with pure H2O, and the opposite face is a similar plane for reactions with pure CO2; these are separated by an axis for pore fluid composition varying between H2O and CO2. Superposition of the PT faces of the model provides the petrogenetic grid. The reactions within the model are represented by divariant surfaces, which may meet along univariant lines. For dissociation reactions, the surfaces curve towards lower temperatures as the proportion of non-reacting volatile increases, and solid-solid reaction surfaces are parallel to the vapour composition axis and perpendicular to the PT axes. The relative temperatures of reactions and the lines of intersections of the surfaces can be illustrated in isobaric sections. Isobaric sections are used to illustrate reactions proceeding at constant pressure with (1) pore fluid composition remaining constant during the reaction, with temperature increasing (2) pore fluid composition changing during the reaction, with temperature increasing, and (3) pore fluid changing composition at constant temperature. The petrogenetic model provides a convenient framework for a wide range of experimental data.

A Method for Measuring Deformation Rates in Hydrogel Structures: Multi-Plane Imaging and Measurement Limitations

2000 ◽  
Author(s):  
Joseph M. Bauer ◽  
David J. Beebe
Keyword(s):  
Cross Sections ◽  
Particle Image ◽  
Three Dimensional ◽  
Local Deformation ◽  
Dimensional Representation ◽  
Volume Changes ◽  
Mechanical Constraints ◽  
Seed Particles ◽  
Three Dimensional Representation ◽  
Image Velocimetry

Abstract A technique for determining the three dimensional motions of hydrogel structures in microchannels is introduced. In developing this technique, we have adapted microscopic particle image velocimetry (μPIV), a method for measuring velocity fields in microfluidic devices. The motions of 1 μm fluorescent seed particles that are incorporated into a hydrogel microstructure (200 μm tall × 400 μm diameter) are tracked over several expansion cycles using microscopy. Combining measurements taken in different planes produces a three-dimensional representation of the motions present during volume changes can be reconstructed. By providing cross sections of the local deformation rates in hydrogel microstructures, this technique allows for the optimization of device designs as well as providing a better understanding of the processes by which hydrogels change volume under mechanical constraints.

Research Progress and Application of Modified Silicon-Based Anode Materials for Lithium-Ion Batteries

2021 ◽  
Vol 1036 ◽  
pp. 35-44
Author(s):  
Ling Fang Ruan ◽  
Jia Wei Wang ◽  
Shao Ming Ying
Keyword(s):  
Electrochemical Performance ◽  
Lithium Ion Batteries ◽  
Volume Expansion ◽  
Anode Materials ◽  
Active Material ◽  
Three Dimensional ◽  
Lithium Ion ◽  
Research Progress ◽  
Ion Intercalation ◽  
Silicon Based

Silicon-based anode materials have been widely discussed by researchers because of its high theoretical capacity, abundant resources and low working voltage platform,which has been considered to be the most promising anode materials for lithium-ion batteries. However,there are some problems existing in the silicon-based anode materials greatly limit its wide application: during the process of charge/discharge, the materials are prone to about 300% volume expansion, which will resultin huge stress-strain and crushing or collapse on the anods; in the process of lithium removal, there is some reaction between active material and current collector, which creat an increase in the thickness of the solid phase electrolytic layer(SEI film); during charging and discharging, with the increase of cycle times, cracks will appear on the surface of silicon-based anode materials, which will cause the batteries life to decline. In order to solve these problems, firstly, we summarize the design of porous structure of nanometer sized silicon-based materials and focus on the construction of three-dimensional structural silicon-based materials, which using natural biomass, nanoporous carbon and metal organic framework as structural template. The three-dimensional structure not only increases the channel of lithium-ion intercalation and the rate of ion intercalation, but also makes the structure more stable than one-dimensional or two-dimensional. Secondly, the Si/C composite, SiOx composite and alloying treatment can improve the volume expansion effection, increase the rate of lithium-ion deblocking and optimize the electrochemical performance of the material. The composite materials are usually coated with elastic conductive materials on the surface to reduce the stress, increase the conductivity and improve the electrochemical performance. Finally, the future research direction of silicon-based anode materials is prospected.

scholarly journals Liquid water infiltration into a layered snowpack: evaluation of a 3-D water transport model with laboratory experiments

2017 ◽  
Vol 21 (11) ◽  
pp. 5503-5515 ◽  
Author(s):  
Hiroyuki Hirashima ◽  
Francesco Avanzi ◽  
Satoru Yamaguchi
Keyword(s):  
Liquid Water ◽  
Laboratory Experiments ◽  
Preferential Flow ◽  
Transport Model ◽  
Three Dimensional ◽  
Water Infiltration ◽  
Flow Paths ◽  
Preferential Flow Paths ◽  
Capillary Barriers ◽  
Wet Snow

Abstract. The heterogeneous movement of liquid water through the snowpack during precipitation and snowmelt leads to complex liquid water distributions that are important for avalanche and runoff forecasting. We reproduced the formation of capillary barriers and the development of preferential flow through snow using a three-dimensional water transport model, which was then validated using laboratory experiments of liquid water infiltration into layered, initially dry snow. Three-dimensional simulations assumed the same column shape and size, grain size, snow density, and water input rate as the laboratory experiments. Model evaluation focused on the timing of water movement, thickness of the upper layer affected by ponding, water content profiles and wet snow fraction. Simulation results showed that the model reconstructs relevant features of capillary barriers, including ponding in the upper layer, preferential infiltration far from the interface, and the timing of liquid water arrival at the snow base. In contrast, the area of preferential flow paths was usually underestimated and consequently the averaged water content in areas characterized by preferential flow paths was also underestimated. Improving the representation of preferential infiltration into initially dry snow is necessary to reproduce the transition from a dry-snow-dominant condition to a wet-snow-dominant one, especially in long-period simulations.

Volume Change Associated to Carbon Partitioning from Martensite to Austenite

2012 ◽  
Vol 706-709 ◽  
pp. 2290-2295 ◽  
Author(s):  
M. J. Santofimia ◽  
Lie Zhao ◽  
Jilt Sietsma
Keyword(s):  
Volume Change ◽  
Chemical Potential ◽  
Theoretical Models ◽  
Carbon Partitioning ◽  
Volume Changes ◽  
Measured Volume

Annealing of martensite/austenite microstructures leads to the partitioning of carbon from martensite to austenite until the chemical potential of carbon equilibrates in both phases. This work calculates the volume change associated with this phenomenon using theoretical models for the carbon partitioning from martensite to austenite. Calculations are compared with experimentally determined volume changes. This comparison reveals that in the case of steels with higher contents of austenite-stabilizing elements, reported volume changes are satisfactory predicted assuming a low mobilily martensite/austenite interface. In the case of a steel with lower additions of austenite-stabilizing elements, experimentally measured expansions are considerably larger than predicted ones. The large measured volume expansions probably reflect the decomposition of the austenite.

scholarly journals Contact Angle Profiles for Droplets on Omniphilic Surfaces in the Presence of Tangential Forces

2019 ◽  
Vol 3 (4) ◽  
pp. 60 ◽  
Author(s):  
Kostoglou ◽  
Karapantsios
Keyword(s):  
Contact Angle ◽  
Contact Line ◽  
Theoretical Perspective ◽  
Three Dimensional ◽  
Real Life ◽  
Suggested Approach ◽  
Droplet Shape ◽  
Tangential Forces ◽  
Contact Line Motion ◽  
Static Conditions

In real life, sessile droplets usually have a three-dimensional shape, making it difficult to understand their forced wetting behavior, both from an experimental and a theoretical perspective. Even in the case of spreading under quasi-static conditions, where the droplet shape is described by the Young–Laplace equation, there is no fundamental approach to describe the contact line evolution. In the present work, a few existing approaches on this issue are analyzed and assessed. It is shown that an experimentally inspired fixed shape for the contact line of droplets that are spreading under the action of tangential forces can be considered equivalent to a theory for contact line motion. There is a lack of experimental data for contact line evolution under arbitrary scenarios of forces. Such data will be very helpful for the further development of the suggested approach to contact line motion. Of particular interest is the case of small contact angle droplets, for which a top view can clearly indicate the contact line location. On the contrary, in such droplets, the direct experimental measurement of contact angle profile is very difficult. This must be estimated theoretically; thus, a special approach has been developed here for this purpose.

scholarly journals The magnetorotational instability prefers three dimensions

2020 ◽  
Vol 476 (2233) ◽  
pp. 20190622
Author(s):  
Jeffrey S. Oishi ◽  
Geoffrey M. Vasil ◽  
Morgan Baxter ◽  
Andrew Swan ◽  
Keaton J. Burns ◽  
...  
Keyword(s):  
Shear Rate ◽  
Angular Velocity ◽  
Laboratory Experiments ◽  
Three Dimensional ◽  
Linear Instability ◽  
Three Dimensions ◽  
Two Dimensional ◽  
Magnetorotational Instability ◽  
Dynamo Action ◽  
Wide Range

The magnetorotational instability (MRI) occurs when a weak magnetic field destabilizes a rotating, electrically conducting fluid with inwardly increasing angular velocity. The MRI is essential to astrophysical disc theory where the shear is typically Keplerian. Internal shear layers in stars may also be MRI-unstable, and they take a wide range of profiles, including near-critical. We show that the fastest growing modes of an ideal magnetofluid are three-dimensional provided the shear rate, S , is near the two-dimensional onset value, S c . For a Keplerian shear, three-dimensional modes are unstable above S  ≈ 0.10 S c , and dominate the two-dimensional modes until S  ≈ 2.05 S c . These three-dimensional modes dominate for shear profiles relevant to stars and at magnetic Prandtl numbers relevant to liquid-metal laboratory experiments. Significant numbers of rapidly growing three-dimensional modes remainy well past 2.05 S c . These finding are significant in three ways. First, weakly nonlinear theory suggests that the MRI saturates by pushing the shear rate to its critical value. This can happen for systems, such as stars and laboratory experiments, that can rearrange their angular velocity profiles. Second, the non-normal character and large transient growth of MRI modes should be important whenever three-dimensionality exists. Finally, three-dimensional growth suggests direct dynamo action driven from the linear instability.

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