Showing papers on "Surface tension published in 2022"
TL;DR: In this paper , the Young's equation and Neumann's equation of state were combined to theoretically compute these three parameters (θE, γSL, and γSG) at reservoir conditions for the H2 and CO2 geo-storage potential.
53 citations
TL;DR: In this paper , the physicochemical characteristics of deep eutectic solvents under the effect of molar ratio of HBAs/HBDs, size of anion, alkyl chain length, and molar mass on the melting point, density, viscosity, conductivity, surface tension, and refractive index have been revealed.
46 citations
TL;DR: The physical principles of capillarity are presented, including examples of how capillary forces structure multiphase condensates and remodel biological substrates.
45 citations
TL;DR: Gemini surfactants consist of two cationic monomers of a surfactant linked together with a spacer as mentioned in this paper , which is the reason for both its high surface activity and its ability to decrease the surface tension of water.
42 citations
TL;DR: In this article , the authors present a critical review of the energy input needed to promote the formation of an emulsion and the type of emulsifying agents necessary to enable the appearance of oil-in-water or waterin-oil emulsion.
38 citations
TL;DR: In this paper , tannic acid (TA) was used to increase the stability of ovalbumin (OVA)-stabilized HIPEs and the binding clusters between OVA and TA were hypothesized by the molecular docking simulation, and the interfacial properties of OVA-TA complexes were investigated by interfacial tension and three-phase contact angle.
37 citations
TL;DR: In this article , the foaming properties of chickpea protein isolate (CPI) subjected to different pH shifting treatment were investigated, and the results indicated that pH shifting under extreme acid or alkaline pH condition significantly enhanced the foam properties of CPI, while the use of ultrasound further intensified this change.
34 citations
TL;DR: In this article, the foaming properties of chickpea protein isolate (CPI) subjected to different pH shifting treatment were investigated, and the results indicated that pH shifting under extreme acid or alkaline pH condition significantly enhanced the foam properties of CPI, while the use of ultrasound further intensified this change.
34 citations
TL;DR: In this article , the authors determined the wettability and interfacial tension of the hydrogen-brine-quartz system using 3D micro-Computed Tomography (CT) methods.
33 citations
TL;DR: In this paper , a review of microfluidic devices to determine the equilibrium and dynamic interfacial tension during droplet formation, and to investigate the coalescence stability of dispersed droplets applicable to the processing and storage of emulsions, are discussed.
32 citations
TL;DR: In this paper , the buckling theory of deformable active polar liquid crystals is used to explain the formation of protrusions in the presence of disclinations, and the instability originates from an interplay between the focusing of the elastic forces mediated by defects and the renormalization of the system's surface tension by the active flow.
Abstract: Growing experimental evidence indicates that topological defects could serve as organizing centers in the morphogenesis of tissues. Here, we provide a quantitative explanation for this phenomenon, rooted in the buckling theory of deformable active polar liquid crystals. Using a combination of linear stability analysis and computational fluid dynamics, we demonstrate that active layers, such as confined cell monolayers, are unstable to the formation of protrusions in the presence of disclinations. The instability originates from an interplay between the focusing of the elastic forces, mediated by defects, and the renormalization of the system’s surface tension by the active flow. The posttransitional regime is also characterized by several complex morphodynamical processes, such as oscillatory deformations, droplet nucleation, and active turbulence. Our findings offer an explanation of recent observations on tissue morphogenesis and shed light on the dynamics of active surfaces in general.
TL;DR: In this article , a self-prepared lower-phase nano-emulsion (LWPNE) was used to reveal the mechanisms of spontaneous imbibition oil recovery, and the results showed that the original 135° (oil-wet) contact angle can be reduced to 32.7° and the IFT is decreased to 0.0038 mN/m.
TL;DR: In this paper , the underlying physical and physicochemical mechanisms of multicomponent droplets during wetting and spreading, induced by evaporation and/or mediated by the vapor field are reviewed.
01 Mar 2022
TL;DR: In this paper , the authors investigated the flotation response of quartz to temperature via micro-flotation experiments, interface property analyses, and theoretical calculations, and demonstrated that increasing temperature contributed to higher flotation recovery of quartz, which enhanced the removal of quartz from hematite.
Abstract: Temperature affects the flotation of quartz in the calcium/sodium oleate (NaOL) system, while there is a lack of understanding of its potential mechanism. Therefore, in this work, the flotation response of quartz to temperature was investigated via micro-flotation experiments, interface property analyses, and theoretical calculations. Flotation results demonstrated that increasing temperature contributed to higher flotation recovery of quartz, which enhanced the removal of quartz from hematite. Surface tension results revealed that higher temperatures lowered the critical micelle concentration (CMC) and surface tension of the NaOL solution, and thus enhanced its surface activity. Solution chemistry calculations and X-ray photoelectron spectroscopy (XPS) measurements confirmed that the increased content of Ca(OH)+ achieved by increasing temperatures enhanced the adsorption amounts of calcium species (acting as activation sites) on the quartz surface. Dynamic light scattering (DLS) measurements verified that the association degree of RCOO− to form (RCOO)22− was strengthened. Furthermore, adsorption density measurements and molecular dynamics (MD) simulations confirmed that increasing the temperature facilitated NaOL adsorption toward the surface of the quartz, which was attributed to the stronger interaction between NaOL and the calcium-activated quartz surface at higher temperatures. As a result, quartz flotation was improved by increasing temperatures. Accordingly, a possible adsorption model was proposed.
TL;DR: In this article , a vibration-actuated omni-droplets rectifier (VAODR) consisting of slippery ratchet arrays fabricated by femtosecond laser and vibration platforms is reported.
Abstract: High-performance droplet transport is crucial for diverse applications including biomedical detection, chemical micro-reaction, and droplet microfluidics. Despite extensive progress, traditional passive and active strategies are restricted to limited liquid types, small droplet volume ranges, and poor biocompatibilities. Moreover, more challenges occur for biological fluids due to large viscosity and low surface tension. Here, a vibration-actuated omni-droplets rectifier (VAODR) consisting of slippery ratchet arrays fabricated by femtosecond laser and vibration platforms is reported. Through the relative competition between the asymmetric adhesive resistance originating from the lubricant meniscus on the VAODR and the periodic inertial driving force originating from isotropic vibration, the fast (up to ≈60 mm s-1 ), programmable, and robust transport of droplets is achieved for a large volume range (0.05-2000 µL, Vmax /Vmin ≈ 40 000) and in various transport modes including transport of liquid slugs in tubes, programmable and sequential transport, and bidirectional transport. This VAODR is general to a high diversity of biological and medical fluids, and thus can be used for biomedical detection including ABO blood-group tests and anticancer drugs screening. These strategies provide a complementary and promising platform for maneuvering omni-droplets that are fundamental to biomedical applications and other high-throughput omni-droplet operation fields.
TL;DR: Wang et al. as mentioned in this paper investigated the effect of surfactants in compound solution on the wetting-agglomeration properties of the bituminous coal dust, and selected anionic surfactant SDS, SDBS and non-ionic surface agents APG0810 and PPG400 for compounding with agglomerated solutions.
TL;DR: Wang et al. as mentioned in this paper investigated the effect of surfactants in compound solution on the wetting-agglomeration properties of the bituminous coal dust, and selected anionic surfactant SDS, SDBS and non-ionic surface agents APG0810 and PPG400 for compounding with agglomerated solutions.
TL;DR: In this article , the authors investigated the use of silica nanoparticles (NPs) with surfactants and polymers to increase the oil recovery from oil fields, and found that the nanoparticles were able to further reduce the interfacial tension (IFT) between the surfactant solution and crude oil.
TL;DR: In this article , the authors reviewed the mechanisms of nanofluids in enhancing oil recovery in terms of interfacial tension reduction, wettability alteration, foam stabilization, emulsion stabilization, structural disjoining pressure, and depressurization-increasing injection.
TL;DR: In this paper , the role and displacement mechanisms of surfactants in chemical enhanced oil recovery (cEOR) processes have been discussed and discussed the key factors to be considered for analysing the fluid displacement in porous media.
TL;DR: In this paper , an attempt has been taken to show the preferential selection criteria of micro-emulsions and nano-mulsions for applications in enhanced oil recovery for mitigating the energy crisis by enhanced recovery.
TL;DR: In this article , the authors describe the various synthetic route for the preparation of fluorinated surfactants and highlight their oilfield applications and highlight the fundamental surface/interface properties of the synthesized surfactant.
TL;DR: In this article , the authors conduct a numerical investigation on high-frequency (∼1 kHz) pulsating electrohydrodynamic jet at low electric Bond numbers ( Boe = 0.15-0.7), and demonstrate the influences of electric voltage, nozzle-to-substrate distance (H), and liquid surface tension coefficient (λ) on the dynamic behaviors and durations of the three jetting stages.
Abstract: Electrohydrodynamic jet printing is a highly promising technology for the fabrication of three-dimensional micro/nanoscopic structures, but the advancement of this technology is hindered by the insufficient understanding of many aspects of its mechanisms. Here we conduct a numerical investigation on high-frequency (∼1 kHz) pulsating electrohydrodynamic jet at low electric Bond numbers ( Boe = 0.15–0.7). By analyzing the entire jetting process using the voltage distribution, electric charge density, and flow field obtained from the numerical results, we overcome the limitations of experimental approach and demonstrate the influences of electric voltage ( Φ), nozzle-to-substrate distance ( H), and liquid surface tension coefficient ( γ) on the dynamic behaviors and durations of the three jetting stages: (1) cone formation, (2) jetting, and (3) meniscus oscillation. Furthermore, as a measure of the relative significance of the electric force to the surface tension force, the impacts of Boe on the jetting process are also examined. Results show that some critical aspects of the pulsating jetting process are closely related to Boe: (1) the transitional values of Boe between the four observed jetting regimes on the variations of Φ, H, and γ apply to all three parameters; (2) the nondimensionalized Taylor cone length scales with Boe according to a power law; (3) the jetting processes that have similar Boe collapse onto a universal profile. These new findings of pulsating electrohydrodynamic jet provide a useful supplement to the currently inadequate comprehension of the complicated electrohydrodynamic jet printing process.
TL;DR: In this article , the authors characterized the peak in the temporal evolution of the normal force and the jump-off of a falling liquid drop, and showed that the magnitude of this peak is determined by the drop's inertia and surface tension.
Abstract: A falling liquid drop, after impact on a rigid substrate, deforms and spreads, owing to the normal reaction force. Subsequently, if the substrate is non-wetting, the drop retracts and then jumps off. As we show here, not only is the impact itself associated with a distinct peak in the temporal evolution of the normal force, but also the jump-off, which was hitherto unknown. We characterize both peaks and elucidate how they relate to the different stages of the drop impact process. The time at which the second peak appears coincides with the formation of a Worthington jet, emerging through flow-focusing, and it is independent of the impact velocity. However, the magnitude of this peak is dictated by the drop's inertia and surface tension. We show that even low-velocity impacts can lead to a surprisingly high peak in the normal force, namely when a more pronounced singular Worthington jet occurs due to the collapse of an air cavity in the drop.
TL;DR: In this article, the effect of SCG on low-rank coal flotation was established from coal surface hydrophobicity, solution surface tension and the forth layer, which showed that SCG increased the concentrate yield by about 12% while its ash content roughly remained the same.
TL;DR: A comprehensive review of surfactant systems that have been used to generate micro-emulsions at different reservoir conditions is presented in this article, which reveals that anionic surfactants are capable of generating a Winsor III type microemulsion, which is optimal in EOR processes.
TL;DR: In this paper, a methodological laboratory assessment of synthesized SAILs was carried out to investigate their applicability for enhanced oil recovery based on their physicochemical evaluation, and the phase behaviour studies further suggested the formation of WINSOR-III micro-emulsion, thus making it a robust performance formulation.
TL;DR: In this article , a unique surfactant extracted from a quinoa plant was introduced for enhanced oil recovery (EOR), which was confirmed by 1H NMR, FESEM, and FT-IR analyses, and the obtained results show that the novel surfactants, at its critical micelle concentration (CMC), contributes to an additional 24.1% of the original oil in place (OOIP) due to a significant reduction in contact angle from 146° to 26.3°, and a substantial reduction in IFT from 33.2 to 8.7 mN/m.
01 Mar 2022
TL;DR: In this article , the influence of nanofluids on coal surface wettability was studied based on the nano drag reduction and injection enhancement technology in the field of tertiary oil recovery.
Abstract: To improve the efficiency of coal seam water injection, the influence of nanofluids on coal surface wettability was studied based on the nano drag reduction and injection enhancement technology in the field of tertiary oil recovery. The composition optimization and performance evaluation of nanofluids with nano-silica and sodium lauryl sulfate as the main components were carried out, and the effects of the nanofluid with the optimal ratio on coal wettability were studied through spontaneous upward imbibition experiments. The results show that the composite nanofluid has a lower surface tension, and the lowest value of the interfacial tension is 15.79 mN/m. Therefore, the composite nanofluid can enhance the wettability of coal. However, its effects on coal samples with different metamorphic degrees is different, that is, low rank coal is the largest, middle rank coal is the second, and high rank coal is the least. In addition, a functional relationship between time and imbibition height is found for pulverized coal with different particle sizes. When the particle size of pulverized coal is 60–80 mesh, the wettability of nanofluid to coal is best. The findings in this paper provide a new perspective for improving the water injection efficiency for coal seams with low permeability.