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Precise stratigraphic characterization and assessment of soil parameters are essential for agricultural and geotechnical engineering. The cone penetration test (CPT) has become one of the most extensively used techniques for soil site assessment, because of its reproducibility, robustness, accuracy, and simplicity. The existing DEM (discrete element method) simulations on CPT are only applicable to dry soil, which cannot consider fluid phase (i.e., pore water) and its interaction with the soil particles. The combined DEM and CFD (computational fluid dynamics) approach is developed to model CPT testing on saturated soils in this study. Several sets of CPT simulations at various penetration rates have been performed by using CFD–DEM coupled analysis. The variation of penetration velocity leads to different magnitudes of fluid force, and the variation in fluid force, in turn, affects the CPT measurement of soil's characteristics. Furthermore, the study extends beyond the properties of the soil itself to explore the complex interplay among soil particles, the surrounding fluid environment, and the penetrometer. The cumulative interactions among these elements highlight the intricate nature of CPT and underline the importance of comprehensive computational models in enhancing our understanding of these dynamics. [ABSTRACT FROM AUTHOR]

The interaction between CO2, formation water, and rock surfaces after CO2 flooding and the mechanism by which it affects CO2 storage were studied in this paper. The results show that variations in the solubility of CO2 in crude oil under pressure are similar to those observed in formation water. The solubility of CO2 increases as pressure increases under a low-pressure conditions. The solubility of CO2 in crude oil increases significantly when crude oil is in a low-viscosity state, and this makes it easier to diffuse CO2 into the oil phase at high temperatures. More resistance is encountered when CO2 diffuses into the liquid-containing space of an irregular core, making the coefficient of diffusion into the oil–water two-phase flow in the porous medium smaller. After the core is corroded by a CO2-saturated aqueous solution, the quartz content in the mineral component increases and the plagioclase and potassium feldspar content significantly decrease. The dissolution of the feldspar leads to the formation of a large amount of secondary kaolinite, thus increasing the kaolinite content. In the early stage of CO2 erosion during dynamic displacement, the combined effect of particle migration and inorganic precipitation leads to a slow growth in core permeability and porosity. As the erosion progresses, the influence of particle migration and inorganic precipitation on permeability gradually decreases, while the porosity of the core gradually increases. The secondary pores play a role, and the erosion of the CO2–water system makes the permeability and porosity of the core gradually increase. During dynamic displacement, CO2 is mainly stored in the reservoir in free and irreducible states. Under the pressure of the reservoir, some of the CO2 participates in erosion reactions and is stored in the rock or the solution in the form of minerals or ions. In addition, a small portion of the CO2 is dissolved in the residual water and residual oil that remain after the dynamic displacement. The results of this paper can provide some theoretical support for the design of a CO2 storage site. [ABSTRACT FROM AUTHOR]

Alginate–gelatin hydrogels are extensively used in bioengineering. However, despite different formulations being used to grow different cell types in vitro, their pH and its effect, together with the crosslinking ions of these formulations, are still infrequently assessed. In this work, we study how these elements can affect hydrogel stability and printability and influence cell viability and metabolism on the resulting 3D prints. Our results show that both the buffer pH and crosslinking ion (Ca2+ or Ba2+) influence the swelling and degradation rates of prints. Moreover, buffer pH influenced the printability of hydrogel in the air but did not when printed directly in a fluid-phase CaCl2 or BaCl2 crosslinking bath. In addition, both U2OS and NIH/3T3 cells showed greater cell metabolic activity on one-layer prints crosslinked with Ca2+. In addition, Ba2+ increased the cell death of NIH/3T3 cells while having no effect on U2OS cell viability. The pH of the buffer also had an important impact on the cell behavior. U2OS cells showed a 2.25-fold cell metabolism increase on one-layer prints prepared at pH 8.0 in comparison to those prepared at pH 5.5, whereas NIH/3T3 cells showed greater metabolism on one-layer prints with pH 7.0. Finally, we observed a difference in the cell arrangement of U2OS cells growing on prints prepared from hydrogels with an acidic buffer in comparison to cells growing on those prepared using a neutral or basic buffer. These results show that both pH and the crosslinking ion influence hydrogel strength and cell behavior. [ABSTRACT FROM AUTHOR]

In-situ fluid phase behavior is important in determining hydrocarbon contents and the multiphase flow through shale reservoirs. The gas-to-oil ratio (GOR) has been recognized as a critical indicator of fluid types. However, little is known about the impact of fluid phase variation across the thermal maturity on shale oil/gas production (e.g., estimated ultimate recovery, EUR). According to the specific gravity ratio of oil/gas, the producing GOR was converted and normalized into a mass fraction of gas in total hydrocarbons (MGOR) to compare North American shale oil/gas plays with Chinese shale oil and hybrid gas-condensate plays. A correlation between MGOR, the fluid phases, and production data was established to identify five phase stages of flow. MGOR varies systematically with the different production zones, which shows promise in rapidly indicating the well production performance and high production stages of shale oil/gas plays. The hybrid shale gas condensate index, Tmax, and total gas contents were integrated to present the fluid types and maturity of shale gas-condensates, which indicates fluid phase and production variation across thermal evolution. The results offer a unique perspective on the shale oil reservoir producibility based on the impact of GOR on fluid phases and EUR from the dominant global oil/gas plays. [ABSTRACT FROM AUTHOR]

In this paper, a mathematical model of multiphase filtration in a deformable porous medium is presented. Based on the proposed model, the influence of the deformation of a porous medium on the filtration processes is studied. Numerical calculations are performed and the characteristics of the process are determined. This paper shows that an increase in the compressibility coefficient leads to a sharp decrease in porosity, absolute permeability and internal pressure of the medium near the well, and a decrease in the distance between wells leads to a sharp decrease in hydrodynamic parameters in the inter-well zone. [ABSTRACT FROM AUTHOR]

Landslide‐induced debris flows can travel long distances. Many field studies, laboratory experiments, and theoretical studies have been conducted to clarify the mechanisms of long‐runout landslides. However, information concerning landslide‐induced debris flows is still inadequate despite several explanations proposed. Thus, we collected various forms of data, including video images and light detection and ranging data, for a landslide‐induced debris flow that occurred on 28 July 2015, in Fukaminato River, Japan, and clarified the debris flow behavior from initiation to deposition. We showed that the water content of the debris flow should only be approximately 30% immediately after landslides occurred at the site. However, a fluid phase‐dominated flow flowed over 1.2 km, expanding the damaged area. We inferred that the fine sediments behaved as part of the interstitial fluid in the debris flow and that, during debris flow deposition, some fine sediments were stored in the interstitial space of the riverbed and did not contribute to forming the skeleton of deposits. We conducted a numerical simulation to test the processes of fluid phase‐dominated flow propagation, focusing on the flow and deposition of fine sediments. Our simulation results suggest that fine sediments' flow and depositional processes significantly influence both the initiation of fluid phase‐dominated debris flow and the travel distance of landslide‐induced debris flow. Plain Language Summary: Landslides can cause debris flows that travel long distances. Although several studies have been conducted to clarify the mechanisms of long‐runout landslides, those based on a series of data from the initiation to the deposition of the debris flow are limited. This is because landslides often occur without any precursor signals. We collected various forms of data, including video images and light detection and ranging data, for a landslide‐induced debris flow that occurred on 28 July 2015, in Fukaminato River, Japan. We then clarified the debris flow behavior from initiation to deposition. Furthermore, debris flow deposition was clarified using a debris flow numerical simulation. At the site, debris flow containing sediments of various grain sizes flowed upstream. A fluid phase‐dominated debris flow containing a large amount of fine sediment flowed downstream. We suggest that, during debris flow deposition, some fine sediments formed a skeleton structure, whereas other sediments were stored within the void space of the skeletal sediments. Our results suggest that the depositional processes of fine sediments may cause fluid phase‐dominated and long‐traveling‐distance debris flow. Key Points: Landslide‐induced debris flow behavior was observed from initiation to depositionFine sediment behaviors in debris flow substantially impact erosion and deposition patterns and the travel distance of landslidesField data suggest that some fine sediments in debris flows may be stored in riverbed interstitial spaces during deposition [ABSTRACT FROM AUTHOR]

Significant petroleum resources occur in the Ordovician carbonate reservoirs of the Tazhong area (Tarim Basin, China) in accumulations of black oil, volatile oil and condensate. However, the factors controlling the distribution of pools with different fluid phases remain poorly understood. Here, we integrate geological and conventional oil/gas geochemical data with an extensive dataset on diamondoids and propose a model for the occurrence of petroleum fluids in the area. Oils in the study area contain low variety and concentration of diamondoids and organic-sulfur compounds (OSCs) and have oil-dissolved wet gas mostly co-generated with oil. In contrast, liquids in the condensate reservoirs are significantly enriched in various types of diamondoids and OSCs, and have dry associated gas with methane enriched in 13C and relatively high content of H 2 S. We interpret that mature gas from deeper Cambrian strata, likely generated from thermally cracked oils and affected by thermochemical sulfate reduction (TSR), invaded the condensate reservoirs. Black oil reservoirs did not receive this late gas charge and this preserved their oil phase. The 1D burial history models and data on fluid inclusions suggest that oil charged all studied Ordovician reservoirs in the Late Permian – Triassic time, while the late gas charge occurred in selected reservoirs in the Late Himalayan time (∼10 Ma). Diamondoids proved to be useful indicators of the late gas charge as their variety and concentrations in liquids from the study area show good correlation with the extent of gas invasion. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Spectroscopic Ellipsometry(SE) used to investigate the lipid bilayer properties. • Ellipsometric measurements (Δ and Ψ) show high sensitivity to their phase state. • SE results are modeled to estimate both thickness and optical constants. • The estimated thickness by SE was confirmed by both AFM and MD simulations. • Optical constant (n) found to have thickness and phase state dependence. Abstract The biological membranes play a crucial role in the various biological processes due to their characteristic physical properties. The parameters such as membrane composition, thickness undulations, and the influence of external stimuli play a crucial role in the phase state behavior of biological membranes. The supported lipid bilayer (SLBs) systems closely represent cell membranes and are often studied to understand their behavior. In the current study, we have implemented spectroscopic Ellipsometry (SE) technique to explore the optical properties of various single component lipid bilayers having different phase state (fluid and gel) under hydrated or native conditions. The measurement of ellipsometric angles ψ and Δ were obtained from SE and were utilized to realize an explicit phase state dependence. Further, we obtained the thickness (t) and refractive index (n) by modeling of these SE results. These results were found to be inter-related to the phase state and lateral organization. The bilayer thickness is further verified against values obtained from coarse-grained molecular dynamics simulations. The proposed method was tested on various lipid bilayers under their native phase state at room temperature and was found to have a correlation with AFM measurements. [ABSTRACT FROM AUTHOR]

The paper presents the research results of a fluid phase overheating and alloying effect on cuprum mechanical characteristics. Careful analysis of poly-thermal cross-sections of electro-resistance proved that in order to obtain the maximum values of cuprum mechanical properties, it should be overheated 30 °С above the temperature threshold of abnormal electro-resistance change of a fluid phase (1320 °С). The paper presents the research results of the influence of thermal and thermo-high-speed treatment of cuprum melting on its structure, crystallization and structure formation processes. Regularities of structure change, crystallization parameters and structure formation depending on overheating and cooling rate of the melt are stated.

Two-stage solvent extraction, involving acetone (light extraction) and tetrahydrofuran (heavy extraction), was used to obtain materials from the fluid component of the coal matrix during the thermoplastic stage of pyrolysis. These extracted materials were characterized using Laser desorption ionization time of flight mass spectrometry, Gas chromatography-mass spectrometer, 1 H nuclear magnetic resonance and Fourier transform infrared spectroscopy. After identifying the different chemical compounds using the type difference technique, their structural transformation behaviour was considered. Results show that the molecular weight distribution of extracted materials was within 576 Da. Fluid phase obtained from the extract contained aromatic (benzene with alkyl) and aliphatic (long-chain unbranched alkanes) components. The quantity of these two materials increased as pyrolysis temperature increased from 400 to ∼450 °C, and then decreased with further increases in temperature from 450 to 500 °C. The overall structural transformation of the fluid phase in thermoplastic stage could be divided into two stages: (a) formation and stabilization of the fluid phase, and (b) the cross-linking and re-attaching of the fluid phase to coal char. In the temperature range of 400 to ∼450 °C, the level of both light and heavy fluid phases increased because of the combination of free radicals with hydrogen formed from the cracking of the coal matrix – resulting in shortening of the aliphatic chain length and improving generation of hydrocarbon in the extract. At higher temperatures, the cross-linking and preferential re-attaching of materials to the coal char caused a decrease in the fluid phase level. In turn, this resulted in the lengthening of the aliphatic chains, which weakened their hydrocarbon-generating potential. These two stages explain the transient behaviour of the fluid phase generated in the thermoplastic stage, and contribute toward a better understanding of the softening and solidification behavior of coal during coking. [ABSTRACT FROM AUTHOR]

Despite the biological significance of sphingomyelins (SMs), there is far less structural information available for SMs compared to glycerophospholipids. Considerable confusion exists in the literature regarding even the phase behavior of SM bilayers. This work studies both palmitoyl (PSM) and egg sphingomyelin (ESM) in the temperature regime from 3 °C to 55 °C using X-ray diffraction and X-ray diffuse scattering on hydrated, oriented thick bilayer stacks. We observe clear evidence for a ripple phase for ESM in a large temperature range from 3 °C to the main phase transition temperature (T M ) of ∼38 °C. This unusual stability of the ripple phase was not observed for PSM, which was in a gel phase at 3 °C, with a gel-to-ripple transition at ∼24 °C and a ripple-to-fluid transition at ∼41 °C. We also report structural results for all phases. In the gel phase at 3 °C, PSM has chains tilted by ∼30° with an area/lipid ∼45 Å 2 as determined by wide angle X-ray scattering. The ripple phases for both PSM and ESM have temperature dependent ripple wavelengths that are ∼145 Å near 30 °C. In the fluid phase, our electron density profiles combined with volume measurements allow calculation of area/lipid to be ∼64 Å 2 for both PSM and ESM, which is larger than that from most of the previous molecular dynamics simulations and experimental studies. Our study demonstrates that oriented lipid films are particularly well-suited to characterize ripple phases since the scattering pattern is much better resolved than in unoriented samples. [ABSTRACT FROM AUTHOR]

The formation of porphyry Cu-Mo deposits hinges critically on the ability of an exsolving magmatic volatile phases (MVP) to efficiently extract the available Cu and Mo from the silicate melt and transport them to the site of mineralization. There has been substantial debate about the relative importance of the critical parameters likely to control metal partitioning among silicate melts and supercritical fluids, vapors, and brines. To explore the relative contributions of key MVP parameters (XNaCleq, fO]2, fS2), we present felsic magmatic Cu-Mo partitioning experiments at both reduced (fO2 = NNO+0.6) and oxidized conditions (fO2 = NNO+2), at high fS2, and over the full range of salinities (XNaCleq) relevant to porphyry deposit formation. The experiments demonstrate that fluid-melt Cu partition coefficients (DCu, f/m) have a dominantly second-order exponential relationship with XNaCleq at relevant salinities, consistent with a (Na, K)CuCl2 ion-pair complexation mechanism. We find a strong linear dependence of Cu partitioning on Cl partitioning between coexisting brine and vapor, in good agreement with limited data from unmodified natural fluid inclusions. Whereas H2S can increase Cu partitioning via (Na,K)CuCl(HS) formation, SO2 has no measureable effect on Cu partitioning. These data allow for quantifying the strong partitioning of Cu out of silicate melts at MVP salinities above ~5 wt%, which will become further enriched into tardo-magmatic brines on phase separation. Our data also highlight that low-salinity (<2-3 wt% NaCleq) oxidized MVPs are not capable of substantially extracting Cu from evolved silicate melts or transporting it to the site of mineralization. We also show that DMo, f/m, linear function of XNaCleq, consistent with mono-chloride (e.g., {Na,K}MoO3Cl), Na-K molybdate (e.g., {Na,K}HMoO4), or thio-molybdate ({Na,K}HMoO2S2) complexation mechanisms at modest salinities (>3 wt%) rather than the Mo-oxy-hydroxy [MoO2(OH)2] complexation observed at lower salinities. The f O2 of the magmatic system has a subordinate effect on DMo, f.m with enhanced partitioning at higher fO2. We use the combined data set to produce expressions for DCu, m and and DMo, f/m as functions of XNaCleq, XH22, and fO2. DCu,f/m = 8.0(±1.4) x 104 [(XNaCleq)² (XH2O)14±2 {1 + 180(±60)(XH2S)}] + 380(±50)(XNaCleq) + 0.8(±0.5) DMo, fm (at NNO+2) =430(±60)⋅(XNaCleq) + 1.5(±0.7)⋅(XH2O). These equations provide Cu-Mo fluid-melt partition coefficients for common arc melt-MVP assemblages as their composition evolves through time and space. Quantitative modeling of the contrasting partitioning behavior of Cu and Mo using these equations will allow for significant improvement in understanding metal extraction and porphyry deposit formation. [ABSTRACT FROM AUTHOR]

The formation of porphyry Cu-Mo deposits hinges critically on the ability of an exsolving magmatic volatile phases (MVP) to efficiently extract the available Cu and Mo from the silicate melt and transport them to the site of mineralization. There has been substantial debate about the relative importance of the critical parameters likely to control metal partitioning among silicate melts and supercritical fluids, vapors, and brines. To explore the relative contributions of key MVP parameters (XNaCleq, fO]2, fS2), we present felsic magmatic Cu-Mo partitioning experiments at both reduced (fO2 = NNO+0.6) and oxidized conditions (fO2 = NNO+2), at high fS2, and over the full range of salinities (XNaCleq) relevant to porphyry deposit formation. The experiments demonstrate that fluid-melt Cu partition coefficients (DCu, f/m) have a dominantly second-order exponential relationship with XNaCleq at relevant salinities, consistent with a (Na, K)CuCl2 ion-pair complexation mechanism. We find a strong linear dependence of Cu partitioning on Cl partitioning between coexisting brine and vapor, in good agreement with limited data from unmodified natural fluid inclusions. Whereas H2S can increase Cu partitioning via (Na,K)CuCl(HS) formation, SO2 has no measureable effect on Cu partitioning. These data allow for quantifying the strong partitioning of Cu out of silicate melts at MVP salinities above ~5 wt%, which will become further enriched into tardo-magmatic brines on phase separation. Our data also highlight that low-salinity (<2-3 wt% NaCleq) oxidized MVPs are not capable of substantially extracting Cu from evolved silicate melts or transporting it to the site of mineralization. We also show that DMo, f/m, linear function of XNaCleq, consistent with mono-chloride (e.g., {Na,K}MoO3Cl), Na-K molybdate (e.g., {Na,K}HMoO4), or thio-molybdate ({Na,K}HMoO2S2) complexation mechanisms at modest salinities (>3 wt%) rather than the Mo-oxy-hydroxy [MoO2(OH)2] complexation observed at lower salinities. The f O2 of the magmatic system has a subordinate effect on DMo, f.m with enhanced partitioning at higher fO2. We use the combined data set to produce expressions for DCu, m and and DMo, f/m as functions of XNaCleq, XH22, and fO2. DCu,f/m = 8.0(±1.4) x 104 [(XNaCleq)² (XH2O)14±2 {1 + 180(±60)(XH2S)}] + 380(±50)(XNaCleq) + 0.8(±0.5) DMo, fm (at NNO+2) =430(±60)⋅(XNaCleq) + 1.5(±0.7)⋅(XH2O). These equations provide Cu-Mo fluid-melt partition coefficients for common arc melt-MVP assemblages as their composition evolves through time and space. Quantitative modeling of the contrasting partitioning behavior of Cu and Mo using these equations will allow for significant improvement in understanding metal extraction and porphyry deposit formation. [ABSTRACT FROM AUTHOR]

The behavior of argon in H 2 O-CO 2 bearing basaltic melts was experimentally investigated in the pressure range 1–5 GPa and at temperatures between 1350 and 1600 °C. Our experimental data simulate the partitioning of argon between an Ar-H 2 O-CO 2 bearing fluid and a silicate melt occurring during magma ascent and degassing. The experimental results show several features: - At a pressure of 1 GPa the variation of H 2 O from 0.35 to about 2 wt.% (at constant CO 2 content) does not induce any systematic variation of argon dissolved in basaltic melt. For higher water contents (> 2 wt.%) we observe a positive effect of water on argon solubility. - In the range of 3–5 GPa, we did not observe any systematic variation of the argon content in the basalt melt for water concentration from 0.35 to 5.3 wt.% and at CO 2 content < 0.5 wt.%. For CO 2 content > 0.5 wt.%, argon concentration in basalt melt decreases from about 3800 to 2400 ppm when the CO 2 content increases from 0.5 to 0.8 wt.%. - At all pressures investigated in the present study, a negligible effect of CO 2 for concentration < 5000 ppm on argon content in the silicate melt is observed. - More importantly (despite all these variations) it seems that the effect of pressure in the range of 1 to 5 GPa is the dominant parameter on argon solubility in basaltic melt. Pressure has a positive effect on argon incorporation in the H 2 O-CO 2 bearing basaltic melt reaching at 3 GPa a concentration of ~ 0.38 wt.%. This maximum of ~ 0.38 wt.% corresponds to 6.8 × 10 − 5 cm 3 g − 1 bar − 1 at standard temperature and pressure, a value of the same order of magnitude as that derived from volatiles free basaltic melts equilibrated with argon. The experimental data can be well described by a thermodynamic model assuming mixing of volatile species and oxygen in the silicate melt. The results can be applied for a better understanding of the fractionation noble gas/noble gas and noble gas/CO 2 occurring in degassing processes during magma ascent. [ABSTRACT FROM AUTHOR]