Water Entrapment Research Articles

Liverpool Land Basement High, Greenland: visualising inputs for fractured crystalline basement reservoir models

Basement highs are large structural features, commonly buried in sedimentary basins (Busby & Azor 2012). They are of interest for natural resources exploration and research because of their ability to influence migration and entrapment of petroleum (Trice 2014) and water, and the deposition of metals (Hitzman 2005; Borg et al. 2012). Three-dimensional (3D) reservoir models (e.g. Shepherd 2009) are built to evaluate and model fluid-filled basement reservoirs (Ringrose & Bentley 2015). However, subsurface data are expensive, difficult to obtain and are often widely spaced. Ideally, basement reservoir models would be constrained by rock, fracture and mineral vein data from appropriate outcrop analogues (acknowledging that subaerial basement rocks have, by definition, a different uplift history than subsurface basement). The Liverpool Land Basement High (LLBH) in Greenland is an uplifted and well-exposed basement high located between two sedimentary basins, and thus provides a valuable analogue for fractured basement-hosted mineral, oil and geothermal reservoirs. 
 The Geological Survey of Denmark and Greenland (GEUS) conducted reconnaissance work on the LLBH in 2018 to assess the quality of the exposure of basement palaeo-weathering profiles and fault-fracture networks. Here, we introduce the LLBH, the concept of fractured basement reservoir modelling, and how studying the LLBH can help enhance reservoir modelling of fractured basement. We present some of our preliminary observations of LLBH fault-fracture networks and discuss how the exposed sediment-basement features and processes might aid industry and research in their top basement mapping activities. We propose that LLBH provides a particularly suitable analogue for industry and research to analyse: (a) multiscale fracture system connectivity, (b) fluid migration and fluid-rock reaction processes, (c) input parameters for basement reservoir modelling and (d) top basement geomorphologies and processes.

A Multiscale Approach for Gas Hydrates Considering Structure, Agglomeration, and Transportability under Multiphase Flow Conditions: I. Phenomenological Model

A new topological model on how gas hydrates form, grow, and agglomerate for oil and water continuous flow, with and without surfactant additives, is presented. A multiscale approach is used to explain how the porous structure of gas hydrates and the affinity between the phases affect the particle morphology and their agglomeration. We propose that gas consumption due to hydrate growth happens mostly in the water trapped inside the capillaries of the hydrate structure near the outer surface of the particles. This approach is herein referred to as the “sponge approach” and is treated as a surface problem, instead of the volume problem often treated in literature (the “shell approach”). Affinity between phases (which in a macro point of view is interpreted as a wetted angle that gives rise to capillarity forces and that can be changed by the use of surfactant additives) describes the preferential entrapment of oil or water inside the hydrate sponge structure. Yet by splitting agglomeration into smaller processes and depending on the morphology of the particles and on the evolution of the porous structure of the hydrates, (i) capillarity bridges may form, causing particles to be sticky, and (ii) water may be available at the outer surface of the particles and may promote consolidation of particle–particle (agglomeration) or particle-wall (deposition). The settling of slurries is treated as a separated solid–liquid flow instability problem once mixture deceleration (due to phase consumption during crystallization) and particle size (due to growth and agglomeration) are known. We also propose a new explanation on how surfactants act as anti-agglomerants in oil continuous flow, differently from the common DLVO theory used in literature, which can only explain anti-agglomeration of particles much smaller than the ones formed over droplets of a very fine dispersion flow.

Trehalose-induced slowdown of lysozyme hydration dynamics probed by EDLS spectroscopy.

We use extended depolarized light scattering spectroscopy to study the dynamics of water in a lysozyme-trehalose aqueous solution over a broad time scale, from hundreds to fractions of picoseconds. We provide experimental evidence that the sugar, present in the ternary solution in quantity relevant for biopreservation, strongly modifies the solvation properties of the protein. By comparing aqueous solutions of lysozyme with and without trehalose, we show that the combined action of sugar and protein produces an exceptional dynamic slowdown of a fraction of water molecules around the protein, which become more than twice slower than in the absence of trehalose. We speculate that this ultraslow water may be caged between the sugar and protein surface, consistently with a water entrapment scenario. We also demonstrate that the dynamics of these water molecules gets slower and slower upon cooling. On the basis of these findings, we believe such ultraslow water close to the lysozyme is likely to be involved in the mechanism of bioprotection.

Evolution of rail surface degradation in the tunnel: The role of water on squat growth under service conditions

Squats on open tracks, as opposed to track inside tunnels, have been reported by railway networks across the world. Theoretical research hypothesised that the hydraulic entrapment of water is critical to crack propagation associated with squat growth. The requirement for a fluid to enable crack propagation provides a rational to why squats vanish as soon as the railway enters a tunnel. However, the metallurgical evidence from the ex-service rails damaged by the presence of water at wheel and rail contact interface is lacking. In the current work, a localised section of rail was found to suffer severe surface damage associated with water dropping from an air-conditioning system located in a tunnel roof. This section of rail represented an ideal controlled location for detailed metallurgical investigation to examine the formation of white etching layers (WELs) under both dry and wet conditions. The location allowed to determine the relationship between WELs and squat initiation; and also to investigate mechanics of water on crack propagation and squat growth of ex-service rail.It was found that the presence of water on the rail surface is not an important condition for WEL formation. White etching layer in dry rails was observed to be associated with a distinguished sub-layer; called brown etching layer (BEL). Brown etching layer is thought to be a development stage of white etching layer. Crack initiation on rails inside the tunnel was confirmed to be caused by ratchetting (severe plastic deformation of the surface layer), with the requirement of the rail top surface to contain WEL. Crack propagation was manly influenced by the presence of water. The metallurgical analysis revealed significant amount of oxides existed along the crack faces. The presence of oxides associated with an absence of shear deformation on the cracks faces revealed that crack growth was driven by Mode I loading (tensile opening) associated with the mechanism of hydraulic entrapment of water. Furthermore, both fracture behaviour of some cracks, and confirmation of the presence of corrosive products inside the cracks by EDS analysis, represent strong evidence that stress corrosion cracking was involved in both crack growth and the observed formation of secondary cracks.

Simulation of Capillary Pressure Overshoot in Snow Combining Trapping of the Wetting Phase With a Nonequilibrium Richards Equation Model

AbstractThe timing and magnitude of snowmelt discharge and subsequent runoff are controlled by both matrix and preferential flows of water through snowpacks. Matrix flow can be estimated using the Richards equation, and recently, preferential flow in snowpacks has been represented in 2D and 3D models. A challenge for representing preferential flow through porous media in 2D or 3D is capillary pressure overshoot in 1D. Soil studies have developed sophisticated and largely realistic approaches to represent capillary pressure overshoot, but it has not been addressed in snowpack water flow models. Here a 1D nonequilibrium Richards equation model is implemented with dynamic capillary pressure and is combined with a new concept of entrapment of liquid water within the pore space. This new model well represented capillary pressure overshoot, as estimated by published capillary pressure measurements in snow samples of various grain sizes under different rates of liquid water infiltration. Three model parameters were calibrated, and their impacts on model outputs were evaluated. This improvement is a substantial step toward better understanding and simulating physical processes occurring while liquid water percolates an initially dry snowpack.

Micro- and macro-scale water retention properties of granular soils: contribution of the X-Ray CT-based voxel percolation method

Water retention in granular soils is a key mechanism for understanding transport processes in the vadose zone for various applications from agronomy to hydrological and environmental sciences. The macroscopic pattern of water entrapment is mainly driven by the pore-scale morphology and capillary and gravity forces. In the present study, the drainage water retention curve (WRC) was measured for three different granular materials using a miniaturised hanging column apparatus. The samples were scanned using X-ray micro-computed tomography during the experiment. A segmentation procedure was applied to identify air, water and solid phases in 3D at the pore-scale. A representative elementary volume analysis based on volume and surface properties validated the experimental setup size. A morphological approach, the voxel percolation method (VPM) was used to model the drainage experiment under the assumption of capillary-dominated quasi-static flow. At the macro-scale, the VPM showed a good capability to predict the WRC when compared with direct experimental measurements. An in-depth comparison with image data also revealed a satisfactory agreement concerning both the average volumetric distributions and the pore-scale local topology. Image voxelisation and the quasi-static assumption of VPM are likely to explain minor discrepancies observed at low suctions and for coarser materials.

In silico study directed towards identification of novel high-affinity inhibitors targeting an oncogenic protein: BRD4-BD1

ABSTRACTBromodomain-containing protein 4 (BRD4) is a member of the bromodomain and extra-terminal domain (BET) family of proteins. It epigentically regulates the transcription of growth-promoting genes and has become an attractive target for the development of anticancer and anti-inflammatory agents. In the current study, we performed an in silico screening of a small-molecule chemical library against the acetyl–lysine binding site of the first bromodomain (BD1) in BRD4 protein. Potential inhibitors identified through virtual screening were further studied through molecular dynamics simulations, water entrapment analysis and Molecular Mechanics (MM)/Poisson–Boltzmann surface area (PBSA) binding free energy calculations. Many of the identified compounds exhibit better G-score (–11.64 kcal∙mol−1 to –10.31 kcal∙mol−1) and predicted binding affinity (–9.66 kcal∙mol−1 to –6.63 kcal∙mol−1) values towards BRD4-BD1 than that of the reference compound (+)-JQ1. Molecular dynamics simulation studies show that in free-form BRD4 the reported conserved water molecules are not retained at their specific positoins due to flexibiliy in the ZA-loop. In BRD4–ligand complexes the number and positions of conserved water molecules depends on the bound ligand. Identified potential inhibitors bind stably at the acetyl–lysine binding pocket of BRD4 and form direct and water-mediated hydrogen bonds with higher occupancy which may contribute to ligand specificity towards BRD4-BD1. Further, through MM/PBSA we calculated the binding free energies of selected compounds, which shows that they have comparable energies to that of (+)-JQ1, while NSC744713 shows better binding free energy.

Different mechanisms on the stabilization of POPC membrane by trehalose upon varied mechanical stress

Trehalose has been proven to be able to protect the membrane from being damaged by dehydration. Since dehydration is accompanied by large mechanical stress, it is meaningful to study the effect of trehalose on the membrane subject to lateral stress for understanding its protective mechanism. In present work, molecular simulations were performed on the POPC bilayers with different amount of trehalose under lateral pressure and tension. The results indicate that trehalose invariably induces increase in the area per lipid Axy and decrease in bilayer thickness hz and ordering degree |SCD|, which mean improved structure of membrane. However, the main roles trehalose plays are slightly different in stabilizing compressed and expanded membrane. Under tensile stress, the water replacement effect plays a leading role. Trehalose reaches as deep as water into the bilayer. Hydrogen bonds (H-bonds) forming between trehalose and lipid compensate the reduction of water-lipid H-bonds. More trehalose will replace more water to form H-bonds with lipid and help to hold the structure together through abundant H-bond bridges of various patterns. Under lateral pressure, the replacement of water is limited since trehalose only interacts with the bilayer surface zone. The sum of water-lipid (W-L) and trehalose-lipid (T-L) H-bond reduces upon addition of trehalose. Nevertheless, the penetration depth of water increases in the presence of trehalose while WL H-bonds become less. At the same time, WL H-bonds lifetime is significantly extended. These facts suggest that water forming H-bonds with phosphate and carbonyl oxygen and locating in bilayer interior is trapped by trehalose which is closer to surface and has longer H-bonds lifetime. It can be speculated that the residual water maintains the effective hydration level and the low ordering degree of membrane. This effect is similar to Water entrapment which takes place in the stabilization of protein by trehalose. Moreover, the presence of trehalose increases the viscidity of the system and makes it easy to vitrify. The membrane becomes stiffer and has more resistance to deformation from the perspective of Ka. The vitrification mechanism is not excluded whether the membrane is compressed or stretched. Our findings could provide some insights in the design of protecting agents and processes.

Field and Remote‐Sensing Evidence for Hydro‐mechanical Isolation of a Long‐Lived Earthflow in Central California

AbstractPersistent motion of slow‐moving landslides has been linked to entrapment of water in slide masses by weak, low‐permeability shear zones at their basal and lateral margins. This so‐called “bathtub effect” should have remotely sensible effects on soil moisture and vegetation health. Here we assess this effect at a seasonally active earthflow in northern California with analysis of soil properties and nine years (2009–2018) of multispectral satellite imagery. The shear zone has low hydraulic conductivity, and the earthflow shows elevated water content relative to its surroundings. Spectral indices suggest that the earthflow is perennially wetter, and its vegetation thrives for longer into the dry season as a result. The magnitude of the bathtub effect is correlated with cumulative multiyear rainfall, and its surface expression disappears during the driest year of the 2012–2015 drought. These findings demonstrate a new method for identifying and monitoring mechanical and hydrological interactions that enable persistent landslide motion.

Slam Loads and Kinematics of Wave-Piercing Catamarans During Bow Entry Events in Head Seas

Centre bow (CB) design for wave-piercing catamarans (WPCs) is a critical compromise between minimization of slamming and protection against deck diving. To inform the design process, this article investigates the slam loads and kinematics during bow entry events in regular head seas for a 112-m WPC with systematic variations to its CB and wet-deck geometry. Model tests using a 2.5-m hydroelastic segmented catamaran considered five different CB configurations, designated as the parent, high, low, long, and short CB. The results indicated that changes in the CB length had little effect on the general kinematic trends obtained for the pitch, heave, and bow vertical displacement at the instant of slamming, but increasing the wet-deck height resulted in an increase in heave (but not pitch) at slamming. Two new design ratios are proposed. The CB immersion depth to arch height ratio showed slamming occurring in the range of 0.3–0.6 depending on the wave encounter frequency and the CB configuration. The CB buoyancy in the encountered waves was estimated by considering both immersion depth and area along the CB in waves through relative motion analyses. It was found that the buoyancy to slam force ratio increased with increasing wet-deck height but not with increasing CB length. This suggests that an optimal CB configuration could be achieved by first modifying the arched cross-structure to reduce the arch filling effect on slamming severity and then maximizing the CB buoyancy to slam force ratio by increasing either the wet-deck height or the CB length. 1. Introduction An above-water centre bow (CB) for improving seakeeping is a feature of modern wave-piercing catamarans (WPCs) (Soars 1993; Boulton 1998; Fang & Chan 2007; Dubrovsky 2014). Figure 1 shows a 112-m Incat WPC with the CB located between the two demihulls. There are several important factors to be considered when designing such a central bow. First, the reserve buoyancy offered by the CB is the primary design factor for providing a pitchrestoring moment and eliminating deck diving in the following waves (Davis & Whelan 2007). Second, the CB configuration can influence the slamming loads in WPCs during bow entry in waves (Lavroff et al. 2013). This is due to the complex fluid-structure interaction in the CB area. When the CB enters waves, the water gradually fills the spaces between the CB and demihulls, referred to here as archways, and may result in complete closure of the archways and slamming in excessive pitch conditions. Finally, the frequency of slamming occurrence is, to some extent, related to the CB design as it contributes to lateral jet flow during the CB entry. As a result, slamming may occur in even partial water entrapment below the arch wet-deck cross-structure, which could be the case in small pitch motions (Lavroff & Davis 2015).

Microfluidization and atomization pressure during microencapsulation process: Microstructure, hygroscopicity, dissolution and flow properties

The interaction between emulsification by microfluidization and the atomizing pressure during spray drying on microcapsule topography, particle size, flow properties, hygroscopicity, and dissolution was evaluated. The blend of chia oil with soy protein isolate and maltodextrin (as wall materials), in ratio 1:4 (active agent-wall materials), was homogenized by high pressure microfluidization and rotor-stator, and then spray dried under different atomization pressures (60, 100 and 140 kPa), at constant air-drying temperature. Microfluidization generated the smallest particles (<3.07 μm), rough surface with nanopores (50–100 nm) and irregularities (indentations) comparing with the particles homogenized by rotor-stator, which showed a smooth surface; these characteristics influence on a greater water entrapment capacity, longer dissolution time and low dissolution capacity. The effect of pressure atomization was less evident; however, a high pressure reduced the particle size, dissolution capacity, and the hygroscopicity.

Water entrapment and structure ordering as protection mechanisms for protein structural preservation.

In this paper, molecular dynamics is used to further gain insight into the mechanisms by which typical pharmaceutical excipients preserve the protein structure. More specifically, the water entrapment scenario will be analyzed, which states that excipients form a cage around the protein, entrapping and slowing water molecules. Human growth hormone will be used as a model protein, but the results obtained are generally applicable. We will show that water entrapment, as well as the other mechanisms of protein stabilization in the dried state proposed so far, may be related to the formation of a dense hydrogen bonding network between excipient molecules. We will also present a simple phenomenological model capable of explaining the behavior and stabilizing effect provided by typical cryo- and lyo-protectants. This model uses, as input data, molecular properties which can be easily evaluated. We will finally show that the model predictions compare fairly well with experimental data.

Formation of Cr(VI) in cobalt containing Cr(III)-based treatment solution

Zinc plated steel was formerly submitted to a Cr(VI)-based passivation treatment leading to enhanced corrosion resistance. However, Cr(VI) compounds were recognized as toxic and carcinogenic. Thereafter, hexavalent chromium was substituted by a safer, yet effective, trivalent chromium-based solution treatment. Due to health hazards, the formation of Cr(VI) species in Cr(III) based conversion coating must be avoided. The present work aims at elucidating the formation mechanism of hexavalent chromium in the Cr(III) conversion coatings particularly obtained from treating agents containing cobalt. It is shown that trivalent chromium compounds in the layer might be oxidized to hexavalent chromium by oxygen in the presence of water and under certain conditions. The presence of Cr(VI) was detected by means of spectrophotometry and the dissolved chromium amount was measured with the aid of ICP-OES. The morphology and structure of the films were observed with the aid of FIB-SEM. The total amount of water in the layers was measured employing Karl Fischer Titration. The results indicate that the morphology of the fluoride containing film with a high density of micropores increases the probability of water entrapment. This leads to the oxidation of Cr(III) to Cr(VI) by oxygen in the presence of water at elevated temperatures.

Integration of core/shell nanoparticle and QCM-D sensors in a single device: A new approach to the in situ detection of solvent content in thin adsorbed films with minimized response to spurious bulk refractive index changes

A combined optical and acoustic wave based setup for the time-resolved determination of solvent content in thin adsorbed layers is presented. Implementation of the novel device is achieved by forming a core/shell nanoparticle sensor based on localized plasmon resonance directly on the surface of a quartz crystal microbalance (QCM) integrated in commercially available QCM-D instrumentation. A peculiarity of the optical sensor is the presence of a “magic angle”, under which changes of the bulk refractive index of the adjacent media do not influence the sensor response. Kinetic studies of fibrinogen adsorption with the combined setup and the optical sensor set to the magic angle show that the surface-bound films contain a considerable amount of water with a dry/wet mass ratio of about 26%. Comparison to literature values suggests that the water molecules are not only firmly bound to the proteins in form of a hydration shell but also entrapped in interstitial regions of the adsorbate. The high water content detected in the films confirms the importance of the presented approach. Direct comparison of the adsorption kinetics for dry and wet mass reveals that water entrapment occurs on a longer time scale than mere protein binding.

Facile microfluidic production of composite polymer core-shell microcapsules and crescent-shaped microparticles

HypothesisCore-shell microcapsules and crescent-shaped microparticles can be used as picolitre bioreactors for cell culture and microwells for cell trapping/immobilisation, respectively. ResultsMonodisperse polylactic acid (PLA) core-shell microcapsules with a diameter above 200μm, a shell thickness of 10μm, and 96% water entrapment efficiency were produced by solvent evaporation from microfluidically generated W/O/W emulsion drops with core-shell structure, and used to encapsulate Saccharomyces cerevisiae yeast cells in their aqueous cores. The morphological changes of the capsules stained with Nile red were studied over 14days under different osmotic pressure and pH gradients. FindingsThe shell retained its integrity under isotonic conditions, but buckling and particle crumbling occurred in a hypertonic solution. When the capsules containing 5wt% aqueous Eudragit® S 100 solution in the core were incubated in 10−4M HCl solution, H+ diffused through the PLA film into the core causing an ionic gelation of the inner phase and its phase separation into polymer-rich and water-rich regions, due to the transition of Eudragit from a hydrophilic to hydrophobic state. Crescent-shaped composite microparticles with Eudragit cores and PLA shells were fabricated by drying core-shell microcapsules with gelled cores, due to the collapse of PLA shells encompassing water-rich crescent regions.

Protein hydration in living cells probed by Fourier transform infrared (FT-IR) spectroscopic imaging.

An application of disrelation mapping to Fourier transform infrared (FT-IR) spectroscopic imaging datasets is provided to reveal different H-bonded water species within a mammalian cell. 2D correlation analysis revealed a disrelation peak at (3420 cm-1, 3220 cm-1), showing the existence of a specific water band at around 3220 cm-1 whose variation of absorbance did not follow the trend of water molecules with a well-coordinated H-bonding network. Disrelation maps constructed with disrelation intensities between (3420 cm-1, 3220 cm-1) and (3420 cm-1, 1540 cm-1) reveal that the disruption of the water network occurs around the interfacial regions between the cell and media, indicating the disintegration of the H-bonding network of bulk water due to the entrapment of water by the protein inside the cell. This hydration effect also becomes apparent around the area adjacent to the cellular nucleus, reflecting the fact that protein synthesis mainly occurs in this region. These results clearly show the presence of different molecular states of water inside living cells, which are not readily identified by conventional analysis methods.

Failure analysis of an aluminum extrusion aircraft wing component

Purpose The purpose of this paper is to deal with the failure analysis of a fractured spar stiffener, extruded from 7075-T6 aluminum alloy, which was found in the central wing, trailing edge structure of a military transport aircraft. The previous loading history and the dominant environmental factors (corrosive and humid atmosphere, water entrapment, etc.) suggest corrosion and fatigue as the principal failure modes, synergistically acting on the wing component. Design/methodology/approach This study presents the failure analysis concentrated on finding evidence of failure mechanisms and plausible root-cause(s) of the fractured spar stiffener. Chemical analysis, stereo and scanning electron microscopy, as well as finite element analysis employed as the main analytical tools for material characterization and failure investigation. Findings The overall evaluation of the findings suggest that the failure caused by a synergy of two mechanisms; a crack initiated in the longitudinal, extrusion direction by an environmentally assisted corrosion attack, then propagated by the superimposed transverse stress field, branched/deflected due to a low crack driving force and extended in a transverse path through a high cycle fatigue process. Finally, the complete fracture occurred as fast fracture, resulted by a ductile overload. Originality/value This paper deals with an industrial damage case study, providing analysis and modeling from structural engineering standpoint. The aforementioned findings concerning the fractured aircraft component allow gaining a deeper knowledge about the mechanisms of crack initiation and propagation which, in turn, can produce a valuable feedback to design, inspection and maintenance procedures. This includes a modified heat treatment from T6 to T73 temper for the redesigned component.

Effect of water entrapment by a hydrogel on the microstructural stability of artificial soils with various clay content

Interactions between soil constituents define soil microstructural stability and are enhanced by swellable organic substances (hydrogels) such as extracellular polymeric substances (EPS), root mucilage or synthetic polymers. This study aims to identify the still largely unknown mechanisms behind hydrogel-induced soil microstructural stability. We hypothesized that soil microstructural stability increased with increasing limitation of hydrogel swelling between soil particles. One- and two-dimensional 1H proton nuclear magnetic resonance relaxometry (1H–NMR relaxometry) measurements were performed with untreated and polyacrylic-acid (PAA) treated artificial soils at various clay content and PAA concentrations. The results on the water distribution and water mobility in the artificial soils were related to their microstructural stability as measured by rheology. PAA treatment significantly increased soil microstructural stability up to five times, especially at high clay content. Soil microstructural stability increased with decreasing rotational mobility of water in the PAA-treated artificial. At the two highest PAA concentrations, the microstructural stability was the highest, although the mobility of water molecules was not further restricted. In artificial soils, the viscosity of hydrogel structures between mineral particles and the additional formation of an external network by polymer-clay interactions such as polyvalent cation bridging seem to promote microstructural stability.

A comprehensive system for AASHTO PP69-10-based pavement rut evaluation using 1-mm 3D pavement surface model

Measurement of pavement rut is critical to highway agencies for both pavement design and rehabilitation. Historically, rut depth is the only pavement permanent deformation indicator collected with various measurement technologies. Recently, the new draft protocol called AASHTO Standard Practice PP69-10 outlines a set of procedures to derive multiple measures of pavement permanent deformation, including percent deformation, water entrapment depth, rut depth, etc. Multiple parameters can be useful for project-level analysis, but may not be realistic indices for overall permanent deformation evaluation at network level. In this paper, a three-step procedure is applied to evaluate the overall permanent deformation. Transverse profile data are collected on over 200 km (125miles) National Highway Systems using the 1-mm PaveVision3D Ultra data collection system. Twelve attributes for characterising permanent deformation are calculated according to the requirement of PP69-10. Scoring functions of these attributes are elicited using utility theory-based methods with statistics of attributes from the collected sample data-sets. Analytical Hierarchy Process is performed for the development of a comprehensive permanent deformation evaluation system. Additive weights are obtained for all attributes based on pairwise comparisons. A case study is conducted to compare current rut depth-based practice with the proposed new comprehensive evaluation system.

Combined quartz crystal microbalance with dissipation (QCM-D) and generalized ellipsometry (GE) to characterize the deposition of titanium dioxide nanoparticles on model rough surfaces

Measuring the interactions between engineered nanoparticles and natural substrates (e.g. soils and sediments) has been very challenging due to highly heterogeneous and rough natural surfaces. In this study, three-dimensional nanostructured slanted columnar thin films (SCTFs), with well-defined roughness height and spacing, have been used to mimic surface roughness. Interactions between titanium dioxide nanoparticles (TiO2NP), the most extensively manufactured engineered nanomaterials, and SCTF coated surfaces were measured using a quartz crystal microbalance with dissipation monitoring (QCM-D). In parallel, in-situ generalized ellipsometry (GE) was coupled with QCM-D to simultaneously measure the amount of TiO2NP deposited on the surface of SCTF. While GE is insensitive to effects of mechanical water entrapment variations in roughness spaces, we found that the viscoelastic model, a typical QCM-D model analysis approach, overestimates the mass of deposited TiO2NP. This overestimation arises from overlaid frequency changes caused by particle deposition as well as additional water entrapment and partial water displacement upon nanoparticle adsorption. Here, we demonstrate a new approach to model QCM-D data, accounting for both viscoelastic effects and the effects of roughness-retained water. Finally, the porosity of attached TiO2NP layer was determined by coupling the areal mass density determined by QCM-D and independent GE measurements.