Tension Reduction Research Articles

Use of corncob and pineapple peel as associated substrates for biosurfactant production.

Biosurfactants are amphiphilic biomolecules with promising tensoative and emulsifying properties that find application in the most varied industrial sectors: environment, food, agriculture, petroleum, cosmetics, and hygiene. In the current work, a 23 full-factorial design was performed to evaluate the effect and interactions of pineapple peel and corncob as substrates for biosurfactant production by Bacillus subtilis LMA-ICF-PC 001. In a previous stage, an alkaline pretreatment was applied to corncob samples to extract the xylose-rich hydrolysate. The results indicated that pineapple peel extract and xylose-rich hydrolysate acted as partial glucose substitutes, minimizing production costs with exogenous substrates. Biosurfactant I (obtained at 8.11% pineapple peel extract, 8.11% xylose-rich hydrolysate from corncob, and 2.8109g/L glucose) exhibited a significant surface tension reduction (52.37%) and a promising bioremediation potential (87.36%). On the other hand, biosurfactant III (obtained at 8.11% pineapple peel extract, 31.89% xylose-rich hydrolysate from corncob, and 2.8109g/L glucose) exhibited the maximum emulsification index in engine oil (69.60%), the lowest critical micellar concentration (68mg/L), and the highest biosurfactant production (5.59g/L). These findings demonstrated that using pineapple peel extract and xylose-rich hydrolysate from corncob effectively supports biosurfactant synthesis by B. subtilis, reinforcing how agro-industrial wastes can substitute traditional carbon sources, contributing to cost reduction and environmental sustainability.

The role of oleosins and phosphatidylcholines on the membrane mechanics of oleosomes

HypothesisOilseeds use triacylglycerides as main energy source, and pack them into highly stable droplets (oleosomes) to facilitate the triacylglycerides’ long-term storage in the aqueous cytosol. To prevent the coalescence of oleosomes, they are stabilized by a phospholipid monolayer and unique surfactant-shaped proteins, called oleosins. In this study, we use state-of-the-art interfacial techniques to reveal the function of each component at the oleosome interface. ExperimentsWe created model oil–water interfaces with pure oleosins, phosphatidylcholines, or mixtures of both components (ratios of 3:1, 1:1, 1:3), and applied large oscillatory dilatational deformations (LAOD). The obtained rheological response was analyzed with general stress decomposition (GSD) to get insights into the role of phospholipids and oleosins on the mechanics of the interface. FindingsOleosins formed viscoelastic solid interfacial films due to network formation via in-plane interactions. Between adsorbed phosphatidylcholines, weak interactions were observed, suggesting the surface stress response upon dilatational deformations was dominated by density changes. In mixtures with 3:1 and 1:1 oleosin-to-phosphatidylcholine ratios, oleosins dominated the interfacial mechanics and formed a network, while phosphatidylcholines contributed to interfacial tension reduction. At higher phosphatidylcholine concentrations (1:3 oleosin-to-phosphatidylcholine), phosphatidylcholine dominated the interface, and no network formation occurred. Our findings improve the understanding of both components’ role for oleosomes.

Yarrowia lipolytica growth, lipids, and protease production in medium with higher alkanes and alkenes

Two strains of Yarrowia lipolytica (CBS 2075 and DSM 8218) were first studied in bioreactor batch cultures, under different controlled dissolved oxygen concentrations (DOC), to assess their ability to assimilate aliphatic hydrocarbons (HC) as a carbon source in a mixture containing 2 g·L−1 of each alkane (dodecane and hexadecane), and 2 g·L−1 hexadecene. Both strains grew in the HC mixture without a lag phase, and for both strains, 30 % DOC was sufficient to reach the maximum values of biomass and lipids. To enhance lipid-rich biomass and enzyme production, a pulse fed-batch strategy was tested, for the first time, with the addition of one or three pulses of concentrated HC medium. The addition of three pulses of the HC mixture (total of 24 g·L−1 HC) did not hinder cell proliferation, and high protease (> 3000 U·L−1) and lipids concentrations of 3.4 g·L−1 and 4.3 g·L−1 were achieved in Y. lipolytica CBS 2075 and DSM 8218 cultures, respectively. Lipids from the CBS 2075 strain are rich in C16:0 and C18:1, resembling the composition of palm oil, considered suitable for the biodiesel industry. Lipids from the DSM 8218 strain were predominantly composed of C16:0 and C16:1, the latter being a valuable monounsaturated fatty acid used in the pharmaceutical industry. Y. lipolytica cells exhibited high intrinsic surface hydrophobicity (> 69 %), which increased in the presence of HC. A reduction in surface tension was observed in both Y. lipolytica cultures, suggesting the production of extracellular biosurfactants, even at low amounts. This study marks a significant advancement in the valorization of HC for producing high-value products by exploring the hydrophobic compounds metabolism of Y. lipolytica.

Oil/water interface behavior of hesperidin methylchalcone and its application in nano-emulsions

The behavior of hesperidin methylchalcone (HMC) at the oil/water interface was examined through experimental and molecular simulation methods, and a nano-emulsions based on HMC was subsequently fabricated. The findings indicated that HMC spontaneously aggregated at the oil-water interface, leading to a reduction in interfacial tension and an increase in interfacial thickness. Furthermore, its glycoside and benzene ring showed tendencies to interact with water and medium-chain triglyceride, respectively. The HMC addition amount (w), homogenization times (n) and homogenization pressure (p) significantly influenced the formation of the nano-emulsions. The nano-emulsion with an oil-droplet size of 277.26 ± 13.62 nm was obtained at w = 1.0 %, p = 200 bar, and n = 6. When compared to the Tween 20 nano-emulsion, the HMC nano-emulsion demonstrated superior storage stability, antioxidant activity, and lutein bioaccessibility. It could achieve the slow release of HMC. These findings not only broaden the application range of HMC but also contribute to the advancement of functional nano-emulsions.

Treatment of Neuropsychiatric Symptoms in Parkinson's Disease With Botulinum Toxin A: A 12 week Randomized, Double-Blind, Placebo-Controlled Trial.

The study aimed to evaluate the impact of Botulinum toxin A (BoNT/A) on neuropsychiatric symptoms in Parkinson's disease (PD) patients. A total of 125 PD patients and an equal number of age- and gender-matched healthy controls were involved. Mental health status was assessed using the Cornell Medical Index (CMI) self-assessment questionnaire. Sixty-four PD patients exhibiting neuropsychiatric symptoms were selected for the controlled study and randomly grouped into treatment and control groups. The treatment group received BoNT/A injections, while the control group received a placebo. The primary outcome measures included depression scores from the CMI and the proportion of patients displaying improvement in neuropsychiatric symptoms at 8weeks post-treatment. The secondary outcome was other CMI scores at 4, 8, and 12weeks post-treatment. The outcomes revealed that PD patients had significantly higher scores in various neuropsychiatric factors compared to healthy controls. At 4weeks post-treatment, the treatment group displayed improvements in depression and tension. At 8 weeks post-treatment, they exhibited significant reductions in depression, anxiety, sensitivity, and tension compared to the control group. Moreover, a notably higher percentage of patients in the treatment group showed improvement in neuropsychiatric symptoms compared to the control group. At 12weeks post-treatment, the treatment group exhibited significant improvements in somatization, depression, sensitivity, and tension. PD patients commonly experience multiple neuropsychiatric symptoms, and BoNT/A has demonstrated efficacy in alleviating these symptoms. Specifically, BoNT/A was found to effectively alleviate somatization, tension, anxiety, depression, and sensitivity in PD patients.

Qualifying interfacial properties of crude oil−water system with the synergistic action of a nano Gemini ionic liquid and conventional surfactants

Surface-active ionic liquids (SAILs) have gained much attention due to their green, stable, and efficient properties. The high costs associated with SAILs have raised concerns in their applications; however, blending with conventional surfactants like sodium dodecyl benzene sulfonate (SDBS) can bring about desired outcomes. Gemini surface-active ionic liquids (GSAILs) have been recognized as more efficient surfactants. Accordingly, this study investigates the influence of a mixture of an imidazolium-based GSAIL, [C4im-C6-imC4][Br2], and SDBS on different aspects of crude oil−water interfacial properties. The findings show remarkable synergy in interfacial tension (IFT) reduction up to 98.8% together with incredibly low IFT value of 0.05 mN m−1. This was with an optimal GSAIL mole fraction of 0.2 in the mixture. Further, the surfactant mixture gives synergies of 52.6% in emulsification and 51.8% in wettability of a quartz surface. These amazing results can be explained by the dominant interactions between the oppositely charged components. In theoretical study, the adsorption of individual surfactants and their mixtures was analyzed based on the Frumkin isotherm and the Rosen model, respectively, further supporting the findings.

Effect of Surfactants on Eliminating Stable Ultrafine Chalcopyrite Froth.

Chalcopyrite is a primary source of copper in nature. However, with the increasing need to process low-grade and complex chalcopyrite ores, overly stable froth is becoming more and more common and poses operational and safety challenges. No reliable strategy has been developed to address the issue. As a new initiative, this study investigated three different structured surfactants, sodium dodecyl sulfate (SDS), sodium dodecylbenzenesulfonate (SDBS), and pentadecafluorooctanoic acid (PFOA), which vary in hydrophobic group, aiming to modify the surfaces of ultrafine chalcopyrite particles and adjust the interfacial tension at the gas-liquid interface to eliminate stable ultrafine chalcopyrite froth. The fundamental hypothesis was that an ideal surfactant structure could adjust the particle surface wettability and interfacial tension to eliminate overly stable froth. Based on contact angle measurements and interfacial tension measurements using a Theta Flow tensiometer by the pendant drop method and the sessile drop method, it was demonstrated that the contact angle played a dominant role in defoaming, while the reduction of gas-liquid interfacial tension had an adverse effect. Additionally, defoaming tests indicated that SDBS had lower defoaming effectiveness than SDS at low surfactant concentrations due to the steric hindrance in its structure, whereas the addition of SDBS could achieve a froth reduction efficiency as high as 93.75% at higher surfactant concentrations due to its stronger hydrophobicity and adsorption capacity to chalcopyrite particles, which could reduce the contact angle from 70 to 37.62°. However, PFOA exhibited lower defoaming effectiveness than both SDS and SDBS due to its lipophobic fluorocarbon tail of PFOA and weaker adsorption capacity to chalcopyrite particles, making it unsuitable for eliminating stable ultrafine chalcopyrite froth.

Understanding the Dynamics of Matrix-Fracture Interaction: The First Step Toward Modeling Chemical EOR and Selecting Suitable Fracturing Fluid in Unconventional Oil/Gas Recovery

Summary The effects of chemical additives on mitigating water blocking and improving oil recovery were experimentally examined for gas-water and oil-water systems in spontaneous imbibition cells. In these attempts, two factors are critically important: (1) understanding the physics of the interaction, whether it is co- or countercurrent, and (2) characteristics of the chemical additives to suitably orient the interaction for specific purposes (accelerate/decelerate matrix-fracture interactions). Co- and countercurrent imbibition experiments were conducted on sandstone rock samples using various oil samples (viscosities between 1.37 cp and 54.61 cp) as well as gas (air). The selected new-generation chemical additives included deep eutectic solvents, cationic/anionic/nonionic surfactants, and inorganic and organic alkalis. We observed that the functionality of the chemicals varied depending on the fluid type, interaction type (co- or countercurrent), and application purposes. For instance, chemicals such as the cationic surfactant cetyltrimethylammonium bromide (CTAB) significantly reduced water invasion into the gas-saturated sandstone cores during fracturing, while chemicals such as the nonionic surfactant Tween® 80 provided considerable oil recovery improvement in the oil-saturated sandstone cores. The surface tension and wettability of the rock surface are crucial factors in determining the suitability of chemicals for mitigating water blockage. In terms of oil recovery, certain chemical additives, such as O342 and Tween 80, may result in a lower recovery rate in the early stage because of their strong ability in interfacial tension (IFT) reduction but could lead to a higher ultimate recovery factor by altering the wettability. Additionally, the introduction of chemicals resulted in notable spontaneous emulsification, especially in countercurrent imbibition, thereby enhancing oil recovery. The spontaneous emulsification and its stability are influenced by factors such as oil drop size, boundary condition, interaction type, IFT, wettability, as well as rock surface charges. The results have implications for understanding the physics and dynamics of matrix-fracture interactions in co- and countercurrent conditions. In addition, they serve as the first step toward selecting appropriate chemical additives in hydraulic fracturing fluid design and enhancing oil recovery in unconventional reservoirs.

Investigating the Feasibility of EOR While Preloading Parent Wells to Mitigate Fracture Hits: An Experimental and Modeling Study

Summary During a fracturing operation in an infill (child) well, pressure and fluid communication between this well and a nearby parent well, known as fracture hits (FHs), can impair the production performance of both wells. A cost-effective strategy to mitigate the FH is to preload the parent well with water during the fracturing of the child well. It has been hypothesized that the production performance of the parent well can be enhanced by the preloading process if proper additives are used in the injected water. We develop a laboratory protocol to physically simulate primary production and surfactant preloading stages using Montney core and fluid samples under reservoir conditions. We investigate the role of wettability alteration, interfacial tension (IFT) reduction, and surfactant’s chemical stability on the performance of enhanced oil recovery (EOR) during the preloading process. An analytical model is developed to predict the volume of leaked-off surfactant and recovered oil using measured pressure-decline data from the preloading stage. This study only focuses on the interactions of preloading fluid with the parent well’s matrix and does not consider the child-parent well interference. Our results demonstrate that 31.8% of the oil is recovered during primary production from large inorganic pores under solution-gas drive mechanism. Under countercurrent imbibition, a nonionic surfactant leaks off into the smaller organic and inorganic pores and recovers an additional 11.8% oil from a depleted core during preloading. The analytical model estimates oil recovery factors close to the experimental data determined by material balance. Core visualizations demonstrate a population of small oil droplets on the rock surface under reservoir conditions. While IFT is reduced to nearly the same extent by either surfactant, only the wettability-altering surfactant yields incremental oil recovery. Zeta-potential measurements indicate that while neither surfactant alters the rock-water surface charge, the wettability alteration is achieved by modifying the oil-water surface charge even at concentrations above the critical micelle concentration (CMC). Based on the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory, the repulsive electrostatic double-layer (EDL) forces are intensified with an increase in surfactant concentration, resulting in enhanced stability of the water film on the rock surface and increased hydrophilicity. Under elevated temperatures, we observe two phenomena, which can adversely affect the performance of a nonionic surfactant: (a) agglomeration of surfactant particles due to reduced solubility in water, reducing pore accessibility, and (b) chemical decomposition of the surfactant, affecting its ability for IFT reduction and wettability alteration.

Muscular tension in ear surgeons during cochlear implantations: does a new microscope improve musculoskeletal complaints?

Musculoskeletal complaints and fatigue are commonly described symptoms in daily work of ear nose and throat surgeons using a microscope. Long ear surgical procedures are associated with prolonged microscope use, which can lead to unconsciously tense and uncomfortable body posture. The digital microscope RoboticScope® allows visualization of surgical site through a Head-Mounted Display, independent from camera head and is therefore much easier on the back, as the sitting position can be adjusted flexibly. Aim of the prospective study was to investigate to what extent the use of a RoboticScope® changes the tension of neck and shoulder muscles of the surgeons in comparison to a conventional tripod microscope. For this purpose, the electric activity of neck and shoulder muscles of surgeons was recorded using surface electromyography during cochlear implantations. Electrical potentials were derived via electrodes on neck and shoulder muscles. The basic tension of those muscles was measured in relaxed position before and after surgery. During microscope use the tension was continued to be measured. A questionnaire recorded parameters such as level of difficulty of operation as well as patient data. Results from 58 operations, 33 of which were performed using a conventional microscope and 25 using a Head-Mounted Display, show a significant reduction in muscular tension during surgery by 40% (p < 0.001) in experienced ear surgeons when using a RoboticScope®, regardless of the surgeon. Our results are in line with the relevance of preventive measures to avoid acute and chronic work-related illnesses/symptoms described in literature.

Achieving the hydrophobic alteration by functionalized nano-silica for improving shale hydration inhibition

Shale hydration is the primary cause of wellbore instability during drilling processes. In this study, two non-fluorinated silane-coupling agents, octyltriethoxysilane (OTES) and (3-Aminopropyl) triethoxysilane (APTES), were grafted onto the nano-silica surface to develop a hydrophobic material (SHM). Various performance characterizations, including infrared spectroscopy, thermogravimetric analysis, surface tension, wetting alteration, capillary self-suction height, bentonite expansion, and shale dispersion, were employed to investigate the shale inhibition properties of SHM comprehensively. Experimental results revealed that SHM could significantly improve shale hydration inhibition. For instance, in a 2 % SHM liquids, the shale hot rolling recovery rate increased from 25.39 % to 83.78 %, and the bentonite expansion height decreased from 7.65 mm to 2.80 mm. The inhibition performance was notably superior to potassium chloride (KCl) and polyether amine (PEA). Inhibition mechanisms analysis unveiled that the outstanding inhibitory effect of SHM was achieved through electrostatic adsorption, wettability alteration, and surface tension reduction. Firstly, SHM contained numerous amine groups that could demonstrate strong adsorption on the clay surface through electrostatic and hydrogen bonding interactions. Secondly, with long hydrophobic alkyl chains, it formed a highly hydrophobic film enveloping the shale surface, effectively preventing water from invading. Thirdly, it reduced liquid surface tension, further minimizing the water infiltration. As a result, the use of SHM significantly enhanced shale hydration inhibition during the shale drilling process.

An evaluation of front seat distance from rear facing child restraint systems in prevention of injury in frontal crash tests

Objectives Elevated head injury incidence in infants compared to toddlers involved as occupants in motor vehicle crashes has been demonstrated in multiple population-representative crash databases. Further, experimental studies have revealed a potential injury mechanism via impact between a rear-facing, CRS-restrained child and the back of the vehicle seat or console on the row in front of the CRS. Subsequently, experimental studies have suggested that bracing the CRS against the seat immediately in front of the CRS could mitigate head injury, but also indicated that more research was necessary. Thus, we investigated the effect of bracing against the front seat, as well as distance from the front seat with rear-facing infant carriers and rear-facing convertibles, with a focus on changes to measured head, neck and chest injury metrics in rear facing CRSs. Further, we examined the effect of using the infant carrier with and without a base on these injury metrics. Methods 34 frontal sled tests at 30 or 35 mph were conducted using a simulated rear-row vehicle seat and structure representing the front seatback. A Q1.5 anthropomorphic test device (ATD) was placed in a single make/model LATCH-affixed rear-facing convertible or single make/model infant carrier; infant carrier without base was affixed with lap and shoulder belt. To evaluate the effect of bracing and distance, tests were conducted with a 300, 140, 70, or 15 mm gap between the CRS seatback and the front seatback, or a touching (0 mm) or braced (-20 mm) condition. Bayesian regression models quantified the effects of various predictors and model uncertainty. Results For tests with the convertible CRS, no head contact was observed between the head and the front vehicle seatback. For the infant carrier, head contact occurred at both 70 and 140 mm distances but not the other distances. On average, the −20, 0, or 15 mm distances yielded a 60% reduction in head injury criterion with 15 millisecond window (HIC15), and a 60% to 80% reduction in neck tension, compared to the 70 and 140 mm distances; chest acceleration also decreased for the convertible seat only. In the case of both carriers and convertibles, each mm of distance the CRS moves away from the front seatback up to 70 mm, adds 5.3 HIC15 points (95% Credible Interval (CrI):[4.6, 6.2]), and 3.5 Newtons (95% CrI: [2.2, 4.8]) of neck tension, on average. Conclusions Placing a rear facing CRS, both convertibles and infant carriers, against or close to the seatback of the seat immediately in front of the CRS reduces head and tensile neck injury criteria in ATDs. The amount of gap between the front seat and the rear facing CRS is strongly and positively correlated with HIC for both convertibles and infant carriers. RF infant carriers with and without a base yield comparable injury metrics and kinematics when touching or nearly touching the back of the front vehicle seatback.

Consistent extinction model for type Ia supernovae in Cepheid-based calibration galaxies and its impact on H0

ABSTRACT The most recent SH0ES measurement of the Hubble constant employs corrections of type Ia supernova magnitudes due to extinction in their host galaxies. These corrections are estimated using a probabilistic model which is trained on Hubble flow ($z\gt 0.03$) supernovae and extrapolated to the calibration galaxies (those with observed Cepheids), despite the fact that the latter are selected based on criteria favouring discy and dust-rich systems. We show that this standard approach underestimates the brightness of reddened supernovae in the high stellar-mass ($M_{\star }\gt 10^{10}\, \mathrm{M}_{\odot }$) calibration galaxies. This can be traced back to the fact that for these galaxies, a low total-to-selective extinction coefficient ($R_{\rm B}\sim 3$) is assumed, while for the low stellar-mass analogues a more standard $R_{\rm B}\sim 4$ is adopted. We propose a minimalistic modification of the extinction model in the calibration galaxies in order to alleviate this systematic effect. The modification is twofold and it involves: (i) the same, Milky Way-like distribution of $R_{\rm B}$ (with mean $R_{\rm B}$ of 4.3 – consistent with the extinction curve used for colour corrections of the Cepheids – and scatter 0.4) and (ii) a modified shape of the $E(B-V)$ reddening distribution while keeping the same effective slope of the supernova peak magnitude–colour relation and the same mean $E(B-V)$ reddening as measured for supernovae in the Hubble flow. We show that this new approach yields a significantly better fit ($\Delta \mathrm{ BIC}=-11$) to the calibration data and results in a lower value of $H_{0}$. Our result is $H_{0}=70.5\pm 1$ km s$^{-1}$ Mpc$^{-1}$ implying a reduction of the Hubble constant tension from $5.2\sigma$ to $2.8\sigma$.

Psychometric properties and Longitudinal Measurement Invariance of the Spanish version of the Alcohol Expectancies Questionnaire Short Form among young adult binge drinkers

ABSTRACT Background: Longitudinal Measurement Invariance (LMI) is critically important to evaluate changes in alcohol expectancies over time. However, past research has not explored the longitudinal properties of the Spanish Expectancy Questionnaire Short Form (EQ-SF). Objectives: To examine the reliability, sources of validity (structural, invariance across sex, and concurrent validity), and LMI of the Spanish EQ-SF among young adults who engage in binge drinking. Methods: Participants (n = 279; 48.4% female) completed the EQ-SF and, two months later, completed it again along with measures of alcohol use, drinking motives, and protective behavioral strategies (PBS). We performed confirmatory factor analysis for structural validity and measurement invariance analysis for longitudinal and sex stability. Results: The eight-factor intercorrelated model (i.e. social facilitation, fun, sexual disinhibition, tension reduction, antisocial effects, negative emotional states, negative physical effects, and cognitive impairments) provided the best fit (χ2(df) = 497.29(224), CFI = .962, RMSEA = .064, SRMR = .049). This model was invariant across sex and time. Reliability coefficients (Ordinal alpha) for each dimension were consistently strong at both time points (from .72 to .93 at T1 and .73 to .91 at T2). Positive alcohol expectancies at baseline were positively related to alcohol use and drinking motives and negatively related to PBS at follow-up, demonstrating predictive validity. Conclusion: Our results support the temporal invariance of the EQ-SF scores among Spanish young adults who engage in binge drinking. The evidence supports the suitability of this measure for accurately assessing changes in alcohol expectancies over time in interventions aimed at preventing binge drinking in young adults.

Enhanced low-cost optimization strategies for antimicrobial rhamnolipid production by Pseudomonas aeruginosa PAO1

The use of advanced biotechnological methods with agro-industrial waste is an outstanding approach for low-cost production. This study aimed to enhance rhamnolipid production by Pseudomonas aeruginosa PAO1 using agro-industrial waste and statistical modeling. The Box-Behnken model significantly increased rhamnolipid yield by 7.6-fold (661.7 ± 2.57 mg/L) at 40 g/L glycerol, 20 g/L glucose, 30 g/L peptone, pH 9, and 40 °C for 5 days. The replacement of glycerol and glucose with prickly pear peel (Opuntia ficus-indica) resulted in an increase of rhamnolipids to 847.3 ± 4.5 mg/L. The rhamnolipid concentration increased to 1521 mg/L after optimizing the air flow rate and agitation speed in the pilot-scale bioreactor. The rhamnolipids showed antimicrobial activity against Candida albicans, Escherichia coli, and Staphylococcus aureus strains. A concentration of 115 mg/L resulted in a 42.3 % reduction of the surface tension from 65 to 37.5 mN/m. The optimization processes using agricultural waste are promising approaches for future low-cost industrial production.

Effect of a Natural Surfactant (Fenugreek Seeds) on Emulsification and Mobilization of Paraffins via Pore-Scale Micromodel Experiments.

The surface characteristics of minerals have been crucial in predicting the interactions between chemicals, particularly in chemical flooding. Thus, this paper evaluates the viability of natural surfactants derived from agricultural products for oil recovery studies using a micromodel filled with paraffinic oil. The study investigates the interfacial tension, viscosity, microscopic, dilution, and oil mobilization characteristics of the natural surfactants. The experimental setup involves conducting interfacial tension measurements between the surfactant solution and paraffinic oil using the Wilhelmy plate method and was found to be 14.2, 10.92, and 9.8 mN/m. Additionally, viscosity measurements and frequency sweep analysis were performed to assess the rheological properties of the prepared emulsion, which was stabilized using a natural surfactant. Microscopic evaluation depicts that, among the prepared emulsions, n-heptane emulsion seems more stable at both 30 and 90 °C. Moreover, dilution studies were conducted for each emulsion system, and the dilution ratio was varied from 1:5 to 1:1 (emulsion/saline solution). It was found that n-heptane emulsion possesses better stability at higher dilution (until a 3:5 ratio). Oil mobilization studies are conducted using a glass micromodel to simulate reservoir conditions and observe the displacement efficiency of the surfactant solutions. The results indicate that natural surfactants exhibit competitive interfacial tension reduction and viscosity modification properties compared to commercial surfactants. Furthermore, oil mobilization studies demonstrate the effectiveness of natural surfactants in enhancing oil recovery from paraffinic oil reservoirs. These findings suggest the potential of natural surfactants derived from agricultural products as sustainable alternatives for improving the oil recovery efficiency in petroleum reservoirs.

Effect of silica nanoparticles on crude oil emulsions stabilized by a natural surfactant from Fenugreek Seeds and polyacrylamide for subsurface oil mobilization applications

Emulsions represent a sustainable method for subsurface resource recovery due to their superior performance in pore plugging, mobility control and interfacial tension reduction. However, the stability of emulsion plays a vital role in determining the success of field implementation. In this work, a novel formulation is reported for emulsions wherein they have been stabilized by natural surfactant extracted from fenugreek seed. In this work, two emulsion systems are reported, that is surfactant polymer and nanoparticle-surfactant-polymer emulsion. Surfactant-polymer emulsions are stabilized by natural surfactant whereas nanoparticle-surfactant-polymer emulsion are stabilized in presence of nanoparticle and natural surfactant. Both the emulsions exhibit shear thinning profile as observed from rheological studies. Nanoparticle-surfactant-polymer emulsions were found to be thermally stable than that of Surfactant-polymer emulsions as evident from microscopic and rheological studies. An increase in temperature has the unfavorable impact on surfactant-polymer emulsion as huge drop in viscosity profile was observed. The viscosity profiles of nanoparticle-surfactant-polymer emulsions were found to be best fitted by the Krieger-Dougherty model with the value of coefficient correlation R2 = 0.99. The contact angle studies showed that NSP solution can reduce the contact angle to much lower value, which is 111˚ to 30˚ whereas surfactant-polymer solution was able to reduce from 116˚ to 57˚ only. Adsorption of silica nanoparticle was also observed in presence of sandstone and decrease in 27.32 % of peak absorbance was observed in span of 20 days. Therefore, finding of the study indicates that nanoparticle-surfactant-polymer emulsions has potential to perform better than surfactant-polymer emulsions, even at elevated temperature, and can be a better and cost-effective alternative to the conventional emulsions used in oilfield applications.

Antioxidant amyloid fibril derived from rice protein hydrolysate as stabilizer towards preparing high-stable emulsion

An antioxidant amyloid fibril was prepared as an emulsifier by fibrillating limited enzymatic hydrolysis-modified rice protein (HRP). The purpose of this study was to investigate the feasibility of using fibrillated HRP to stabilize oil-in-water emulsion. A free radical scavenging assay revealed that the antioxidant activity of fibrillated HRP was 2.09 times higher than that of native rice protein. Fibrillated HRP demonstrated a marked reduction in interfacial tension, increased surface hydrophobicity and contact angle (> 80°), and rapid adsorption to the interface, with 35.34 ± 2.43% interfacial adsorbed protein content. The fibrillated HRP barriers resisted environment stresses such as NaCl, pH variations, long-term storage, while reducing lipid oxidation degree. Additionally, fibrillated HRP-based emulsion was more effective in protecting β-carotene from degradation compared to other samples. These findings provide theoretical support for the development of rice protein-based antioxidant emulsifiers and modification of emulsifying properties of plant proteins.

Interfacial tension and contact angle of asphaltenic and resinous model oil in the presence of binary salts mixtures

Using smart or low salinity waters known as green processes gained increasing attention due to their unique features and their positive impacts on the environment. In light of this fact and since there is limited knowledge about the effects of salts under engineered concentrations or binary mixtures and crude oil fractions on the interfacial tension (IFT) reduction and wettability alteration of the resinous (RSO) and asphaltenic synthetic oil (ASO), the current investigation is designed and performed for the first time. Moreover, the dynamic behavior of the IFT variation was carefully investigated and the relaxation time was obtained and modeled to see the impact of mono and divalent salts individually and in binary conditions. The relaxation times revealed that the lowest adsorption times were obtained for NaCl/CaCl2 brine regardless of the examined oil types of ASO and RSO due to the high movement affinity of the polar functional groups toward the interface consequently reducing the required time for coverage and packing of active agents at the interface. Finally, the measured contact angle values revealed a significant effect of binary salts on the wettability alteration toward strongly water-wet conditions, especially for the RSO and ASO compared with crude oil.

Revisiting the concordance ΛCDM model using Gamma-Ray Bursts together with supernovae Ia and Planck data

The Hubble constant, H0, tension is the tension among the local probes, Supernovae Ia, and the Cosmic Microwave Background Radiation. This tension has persisted for decades and continues to puzzle the community. Here, we add intermediate redshift probes, such as Gamma-Ray Bursts (GRB) and Quasars (QS0s), to check if and to what extent these higher redshift probes can reduce this tension. We use the three-dimensional fundamental plane relation among the prompt peak luminosity, the luminosity at the end of the plateau emission, and its rest frame duration. We find similar trend in GRB intrinsic parameters as previously seen in Pantheon-Plus intrinsic parameters. We find an apparent 3.14σ tension for the GRB intrinsic parameter b. Indeed, this tension disappears and the parameters are actually compatible within 2.26σ. Another interesting point is that the 3D relation plays an important role in conjunction with Supernovae data with Pantheon Plus and that this apparent discrepancy shows the importance of the correction for selection biases and redshift evolution. The incorporation of redshift evolution correction results in a reduction of the GRB tension to 2.26σ when adjusting correction parameters. We envision that with more data this indication of tension will possibly disappear when the evolutionary parameters of GRBs are computed with increased precision.