Liquid Composition Research Articles

Recent Experimental Advances in Solid–Liquid Composites for Impact and Blast Mitigation

The development of high-performance composites for mechanical energy dissipation during impact or explosive events is of vital importance for the safety of personnel and infrastructures. Solid–liquid composites are an emerging class of energy absorbers where a liquid-phase filler is seamlessly integrated into a solid matrix to enhance the impact resistance of the protection target. This innovative approach leverages the distinct properties of both phases and the unique interactions between them to achieve superior performance under high-impact conditions. This paper aims to review the liquid-phase materials used in solid–liquid composites, ranging from neat liquids to complex fluids, including liquid nanofoam and shear-thickening fluids, to provide an in-depth analysis of the fundamental physics underpinning the resulting solid–liquid composites, and to explore how their unique properties contribute to enhanced impact resistance and energy absorption. Furthermore, this paper evaluates the advantages and limitations of these solid–liquid composites and offers insights into future directions for the development of solid–liquid composites in various fields, including personal protective equipment, automotive safety systems, and structural protection.

Thermal and hydrodynamic effects in variable geometry nanofluid transport with Thermo-Responsive liquid Composites: Dynamics of entropy generation

In this communication, the authors focused on energy loss during the flow of hybrid nanofluid in expanding/contracting channels. The goal is to determine how, in real-world applications, hybrid nanofluids can maximize energy efficiency and reduce entropy production, hence assisting in the development of more effective and sustainable thermal management systems. It is well documented that heat transfer is enhanced due to the presence of nanoparticles in a base fluid and hence decreases energy loss in the system. The second law of thermodynamics defines that heat transfer is not ideal; hence, entropy in a system always rises. Suitable measures can be taken to minimize energy loss. One method is to use a nanofluid, if multiple nanosized particles are used; it is named a hybrid nanofluid. In this communication, a comparative analysis of simple and hybrid nanofluids is provided. A mathematical model outlining the dynamics of the flow is provided. The upper plate acts as a porous plate that is contracting/expanding and through which coolant hybrid nanofluids enter the channel. The lower plate remains stationary and is heated externally. The equations governing the flow are converted into ordinary differential equations by employing the similarity transformation. These ODEs are then solved analytically to get the series solution by using HAM along with the given boundary conditions. The entropy equation is modelled using the Clausius Duhem inequality. Copper and silver nanoparticles are combined with water. The impacts of different dimensionless parameters on stream function, velocity profile, Nusselt number, entropy, and Bejan number are discussed, and their results are shown graphically.

Application of whey protein microparticulates in the production of ice cream and other dairy products

The aim of this paper is to systemize data on the use of whey protein microparticulates (WPMP) in production of ice cream and other dairy products. Information about the essence of the microparticulation process and methods for WPMP production is given. Data on the composition and physico-chemical properties of liquid and dry WPMP are presented. An effect of sizes of WPMP particles on quality characteristics of products made with their use is described. The majority of the analyzed studies indicate that the diameter of particles is 1.0–2.5 µm. However, contradictory data were obtained for this indicator — if the results of all studies are taken into consideration, a size of conglomerates can be 0.5 to 12 µm. These sizes are comparable with parameters of fat globules, which allow receptors of the human oral cavity to perceive them identically. Due to this, WPMP can be used as an imitator of milk fat. It is noted that the microparticulation process enables producing WPMP with targeted functional properties, namely, with particular characteristics by indicators “solubility”, “water holding capacity”, “gel formation”, “emulsifying and foam forming properties”. Information about the specific features of using and dosing WPMP in fermented milk products, such yogurt, kefir, curd cheese and cheese, is given. A special attention is paid to the results of the investigation of using WPMP in ice cream. It is noted that most often scientists used WPMP to make up for the sensation of fatness in defatted and nonfat dairy products. The ability of WPMP to increase the biological value of food products is highlighted. It has been concluded that WPMP enables formation of soft and elastic structure in low-fat dairy products, intensification of milky color and restriction of ice crystal growth in frozen desserts by binding and equally distributing moisture. The data were obtained about the clinical investigation of an effect of ice cream with WPMP on the health of children and adults. The negative effect of WPMP on the indicators of clinical analyses of humans and their health was not revealed.

Boosting cesium retention efficiency with polyoxometalate-ionic liquid composites: Insights into {WO6} octahedral affinity

Commonly used polyoxometalate (POM) adsorbents exhibit high cesium (Cs) adsorption capacity. However, its impotent ability to sequester adsorbates poses a risk of Cs migration in radioactive waste decontamination and disposal. By leveraging the cesium affinity of POMs and the regulatory properties of ionic liquids (ILs), POM-IL composites hold promise for mitigating the risk of cesium migration through efficient adsorption and retention. Herein, we designed two POM-ILs composed of the phosphotungstate anion (PW) and tetrabutylammonium cation (TBA), i.e., the {WO6}-saturated TBA-PW12 and mono-lacunary TBA-PW11, for the capture and retention of aqueous Cs. The composites were then characterized, and the performance and mechanism of Cs uptake were investigated. TBA-PW12 exhibited ∼300 nm aggregate of particles around 20–60 nm. TBA-PW12 retained the Keggin structural features of PW12O403−, which was proven essential for the binding of Cs+. With a retention efficiency of 97.3% in an NH4Cl eluent and a maximum adsorption capacity of 400.9 mg/g at 338 K, TBA-PW12 exhibited superior Cs capture and retention compared to the POM-IL derived from common Cs adsorbent phosphomolybdate. The Cs adsorption onto TBA-PWs achieved equilibrium within 180 min. Cs uptake by TBA-PWs was monolayer chemisorption of Cs+ accompanied by H+ release, and the removal efficiencies stabilized around initial pH 5–10. Due to intense affinity between {WO6} and Cs+, TBA-PW12 efficiently sequestered Cs + through {WO6} octahedra so that the {WO6}-saturated TBA-PW12 presented better Cs uptake performance than the mono-lacunary TBA-PW11. The IL anion [N(C4H9)4]+ provided a composite-water biphasic interface for aqueous Cs adsorption, while retaining the ability of POM cation PW12O403− to form a stable structure with Cs via its affinity to {WO6} octahedra. These findings support the design of POM-IL composites as efficient adsorbents for capturing and retaining Cs, aiding in the decontamination and safe disposal of radioactive waste, thereby minimizing the risk of nuclide leakage into the environment.

Effects of freebase/protonated nicotine concentration, liquid composition and electrical power on throat hit in direct-to-lung vaping: theory and clinical measurements

BackgroundFor decades, the tobacco industry has engineered the sensory characteristics of combustible tobacco products including the degree of harshness experienced at the back of the throat. Commonly referred to as...

Methods of active friction control in the presence of lubricant compositions with mesogenic additives

Purpose of research. The aim of the study is to systematize the latest literature data related to the modulation of the friction coefficient by external fields when using lubricant compositions with liquid crystal mesogens and polymer composites.Methods. The article considers the methods of tribological tests using various schemes of friction pairs (cylinder-disk, pin-on-disk). Some commonly used methods of applying coatings to the elements of friction pairs are considered: ion beam-assisted deposition, chemical and physical thermal spraying, molecular layer deposition, photopolymerization, etc. Of the discussed methods of characterizing tribosystems, the following are indicated: dielectric spectroscopy, Raman scattering, polarization optical microscopy, nuclear-physical methods (positron annihilation spectroscopy and Xray diffraction).Results. The article systematizes modern trends in the development of modulated modes of operation of tribological circuits with lubricant compositions containing liquid crystals and polymer composites. The following approaches are used to implement active control of the friction coefficient: 1) modulation of friction by an electric field, 2) modulation of friction by a temperature field, and 3) modulation of friction on optical gratings under light irradiation. These approaches take into account the changed characteristics of the lubricant associated with the use of mesogenic additives, modes of exposure to electromagnetic and thermal fields, electrical characteristics, geometry of the surface of friction pairs, and provide the values of tribological characteristics (friction coefficient and wear) that are achieved as a result of friction modulation.Conclusion. A positive effect of mesogenic additives of liquid crystals and polymers on tribological characteristics with active control of the friction coefficient has been established: a decrease in the friction coefficient is observed, which helps to reduce material wear.

Enhanced thermal performance and stability of non-gallium liquid metal composites

This paper presents a study on the thermal performance and stability of non-gallium liquid metal (BiPbInSnCd alloy with melting point 47 °C) composite. It has been found that incorporating copper particles and copper foam into the non-gallium liquid metal can help to enhance the overall thermal conductivity, and achieved longer lifetime than gallium-based liquid metal composite. We have demonstrated that the average thermal conductivity of non-gallium liquid metal composite with filler weight ratio of 44.4 % can reach as high as 28.9 W·m−1·K−1. The improvement mechanism and the impact of preparation methods on the thermal performance have been also investigated.

Application of Reservoir Blockage-relieving in Low Permeability Carbonate of Jingbian Gas-field

Abstract Jingbian gas-field is a low-permeability and lithological gas reservoir with strong reservoir heterogeneity and poorly physical properties. As the gas-field is getting older and older, its gas wells start to produce less, and have growing difficulties to lift water and finally fail to work normally and steadily. One inborn factor lies in the unstable liquid composition of Jingbian gas-field: salty formation water with easy-fouling ions and acidic gas such as CO2 and H2S. Living in the underground for a long time these active materials prone to make the forming of water blocking and the solid deposition, which will weaken gas flow ability and threaten the production. After a detailed study on the plugging, there are three kinds of blocking divided: abruptly impurity blocking, slowly water locking, and energy deficiency. To relieve these blocking, methods have been put forth and carried out in field with achievement. The successful application has brought blockage gas wells solutions in Jingbian gas-field.

A greener approach for physical separation of polycotton textile waste

Most textile waste ends up in the landfill. Clearly, enhancing textile recycling is urgently needed. For circularity, efficient means for separating the constituents of the textile blends is crucial. Targeting the popular polycotton textile blend, a method was developed to physically separate cotton and PET (polyethylene terephthalate) from waste textiles. First, the waste polycotton textile was milled into smaller fibers to mitigate entanglement. Then, leveraging the relatively higher hydrophilicity of cotton, three liquids (namely, water, mineral oil, and ethanol) were mixed to form a two-phase liquid-liquid system, which induced the preferential segregation of cotton to the water-rich bottom liquid phase. Factors studied included liquid composition and milling method. The best-performing liquid mixture allowed for 84.7 % of the cotton and 85.5 % of the PET from the waste polycotton (WPC) sample to be recovered respectively from the bottom liquid phase (BLP) and top liquid phase (TLP). The separation effectiveness can be further enhanced if fiber entanglement issue can be mitigated. The recovery of about 99.9 % PET and 86.7 % cotton from a prepared mixture of pure cotton and pure PET textile wastes is a case in point, demonstrating the efficacy of the method that is fast, at ambient condition, and does not require extensive chemicals. While the interwoven design of cotton and PET in textiles confers benefits like comfort and strength, the resulting entanglement is detrimental for circularity. SynopsisAn eco-friendly yet rapid two-phase liquid-liquid system was developed for separating polycotton textile fibers, aimed at enhancing sustainability and circularity

Mean-field homogenization of liquid metal elastomer composites: comparative study and exact dilute solution of core–shell inclusion

Liquid metal-elastomer composites (LMECs) have gathered significant attention for their potential applications in various functional stretchable devices, with inclusion sizes ranging from micrometers to nanometers. These composites exhibit exceptional properties, such as high electric permittivity and thermal conductivity, surpassing those of the elastomer matrix, thus enabling a broader range of applications without compromising the material's stretchability. To investigate the diverse effective elastic and functional properties of LMECs, micromechanics-based homogenization method based on Eshelby's inclusion solution are invaluable. However, the extreme contrast in elastic constants among the phases in LMECs, particularly for nanosized inclusions where a considerable amount of stiff metal oxide forms around the inclusions, can lead to critical failure in predicting effective properties if inadequate homogenization approach is employed. In this study, we present multiple mean-field homogenization approaches applicable to LMECs with core-shell morphology, namely: (i) multi-phase, (ii) sequential, (iii) pseudo-grain, and (iv) direct approaches. We compare the accuracy of the models concerning effective elastic, thermal, and dielectric properties, evaluated against numerical homogenization results and compared with reported experimental data. Specifically, we highlight homogenization scheme utilizing exact field solutions of dilute core-shell inclusion, emphasizing the importance of accurately capturing the field in the micromechanics of LMECs. Furthermore, we demonstrate that widely utilized interphase model could not properly resolve the core-shell morphology and thus should be avoided. This comprehensive assessment provides critical insights into the proper homogenization strategies for designing advanced LMECs with precise prediction of effective properties.

Chemically Tailored Growth of 2D Semiconductors via Hybrid Metal-Organic Chemical Vapor Deposition.

Two-dimensional (2D) semiconducting transition-metal dichalcogenides (TMDCs) are an exciting platform for excitonic physics and next-generation electronics, creating a strong demand to understand their growth, doping, and heterostructures. Despite significant progress in solid-source (SS-) and metal-organic chemical vapor deposition (MOCVD), further optimization is necessary to grow highly crystalline 2D TMDCs with controlled doping. Here, we report a hybrid MOCVD growth method that combines liquid-phase metal precursor deposition and vapor-phase organo-chalcogen delivery to leverage the advantages of both MOCVD and SS-CVD. Using our hybrid approach, we demonstrate WS2 growth with tunable morphologies─from separated single-crystal domains to continuous monolayer films─on a variety of substrates, including sapphire, SiO2, and Au. These WS2 films exhibit narrow neutral exciton photoluminescence line widths down to 27-28 meV and room-temperature mobility up to 34-36 cm2 V-1 s-1. Through simple modifications to the liquid precursor composition, we demonstrate the growth of V-doped WS2, MoxW1-xS2 alloys, and in-plane WS2-MoS2 heterostructures. This work presents an efficient approach for addressing a variety of TMDC synthesis needs on a laboratory scale.

Enhanced CO2 conversion through confinement of cross-linked ionic polymer within the pores of porous carbon materials

It is crucial to employ an integrated catalyst to avoid the complications of the recovery process. This work reports the fabrication of porous carbon@ionic liquid (PC@IL) composites with readily accessible active ion sites, achieved by confining cross-linked ionic liquid (IL) within the channels of porous carbon (PC). The incorporation of porous carbon not only confines the IL within its framework, creating microsites for CO2 adsorption and conversion, but also simplifies catalyst recovery. The results indicate that PC@IL composites exhibit excellent cycloaddition activity towards CO2 in a co-catalyst- and solvent-free environment. Notably, PC@IL(C)-24 demonstrates remarkable catalytic performance across various epoxides under 1 bar of CO2, with yields above 90 % at 90 °C for 12 h, and achieving a remarkable styrene carbonate yield of up to 92.8 % under a CO2 pressure of 1 bar (at 100 °C for 12 h). Control experiments confirm that the confinement effect exerted by N,S co-doped carbon on cross-linked IL plays a pivotal role in enhancing both stability and activity of PC@IL composites, thereby providing novel insights for designing functionalized porous carbon catalysts for CO2 cycloaddition conversion.

Ultra‐Broadband and Reconfigurable Liquid‐Based Microwave Metasurface Absorber

Liquids, with their advantages of fluidity, ease of shaping, and tunability, have exhibited promising potential in the creation of reconfigurable metamaterials (MMs). Water, being the ubiquitous liquid and cost‐effective resource on Earth, has been utilized for the construction of liquid‐based microwave metasurface absorber (MSA). However, due to the challenges associated with integrating microfluidics with MMs in both design and manufacturing, current MSs exhibit narrow frequency bands, particularly constrained at lower frequencies. Herein, a reconfigurable solid–liquid composite of liquid‐based MSs, utilizing the interbedded structure of cones, is proposed for ultra‐wideband microwave absorption. When water is used as the filling medium, the absorption rate exceeds 90% across a wide frequency range from 5.9 to 50 GHz. Upon substitution with ionic liquids, the frequency range demonstrating absorption efficiency exceeding 90% extends from 3.3 to 50 GHz. Furthermore, it is confirmed that the designed MSA demonstrates exceptional stability when subjected to oblique incidence and shows a high degree of insensitivity to polarization, highlighting its robust applicability. The low‐cost, easily manufacturable, and ultra‐wideband liquid‐based MSA holds promising potential for applications in radar countermeasures, energy harvesting, radiation protection, and other related fields.

Pre-mixed small engine fuels (SEFs): Ignitable liquid analysis, canine detection, and a discussion of formulation changes

A variety of types and brands of pre-mixed small engine fuels (SEFs) were analyzed by gas chromatography-mass spectrometry (GC–MS) to determine their ignitable liquid composition. Additionally, many of these brands and fuel mixes were tested six years apart, first in 2018 and again in 2024, to determine if any formulation changes had occurred. All tested products were comprised of a range of isoparaffinic content, and most also contained at least one aromatic compound. One product marketed as a fuel treatment to fix ethanol-related issues contained 2-butoxyethanol. To determine Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) ignitable liquid detection canine (ILDC) response to the specific combination of ignitable liquids in these products, ILDC teams searched representative samples of the SEFs with no detection difficulty shown for the vast majority of these products. Reporting the ignitable liquid classification of SEFs would be dependent upon individual forensic science service provider (FSSP) protocols and the appearance of the ignitable liquid in casework data. The classification possibilities for these mixtures are discussed, including a case example of data resembling an SEF.

The reduced alloy in Earth's upper mantle: Experimental constraints on Fe-Ni-S-C(-O) melt compositions and deep mantle oxygen fugacity (5–16 GPa)

High-pressure experiments conducted at upper mantle conditions reveal increased Fe3+ contents in majoritic garnet with increasing pressure. Consequently, at ∼8 GPa, Fe2+ disproportionation is expected to generate Fe0, leading to a higher metal/sulfur ratio of the initially present monosulfidic melt. This study experimentally investigates equilibrium systematics between the reduced Fe-Ni-S-C(-O) melt and mantle silicates at 5–16 GPa and near-adiabatic temperatures (1420–1590∘C), aiming to constrain the alloy melt composition in equilibrium with bulk silicate Earth-like (BSE) mantle silicates. As analysis of unquenchable liquid alloys requires large melt pools, experimental charges were designed towards a 50:50 ratio of alloy:silicates, with Fe/Ni ratios, sulfur and carbon scaled to correspond to a BSE with 200–250 ppm S and 100–150 ppm C.Observed phase assemblages consist of Fe-Ni-S-C(-O) melt (metal/(S+O): 0.9–3.5, Ni/(Fe+Ni): ∼0.3–0.6 and 0.2–1.6 wt.% oxygen) saturated with graphite/diamond and coexisting with olivine/wadsleyite (XMg: 0.76–0.91), garnet and cpx ± low-Ca pyroxene. Oxygen fugacities (fO2) range from -0.5 to +4.0 relative to the iron-wüstite (IW) buffer. In most runs, Fe0–Fe2+ redox equilibration affected silicate XMg's, resulting in values <0.90. Therefore, an empirical model was developed to predict KDNi-Fealloy-olivine, allowing to recalculate the experimental results for a primitive BSE mantle composition with XMg of 0.90.Modeling BSE, the alloy's metal/(S+O) increases from 1.1 to ∼7 while Ni/(Fe+Ni) decreases from 0.35 to 0.19 at 5–16 GPa. With BSE-like S concentrations, the abundance of the Fe-Ni-S-C(-O) melt increases from 600–750 ppm at 5 GPa to ∼3800 ppm at 16 GPa, 100–150 ppm bulk carbon lead to graphite/diamond saturation to ∼14 GPa. Finally, a method is presented to derive fO2 from modeled liquid alloy compositions, which act as a “redox-sensor”. For a BSE-like mantle with 250 ppm S, fO2 decreases from IW+2.6 at 5 GPa to IW at 8 GPa, further decreasing to IW-1.0 at 12–16 GPa.

The Sulfur Conversion Functional Microbial Communities in Biogas Liquid Can Participate in Coal Degradation.

The addition of biogas liquid is a practical way to improve the yield of biological coalbed methane. The microbial composition in biogas liquid is complex, and whether it could participate in the sulfur conversion of coal remains unknown. In this study, sulfur conversion-related microbial communities were enriched from biogas liquid, which was dominated by genera Anaerosolibacter, Bacillus, Hydrogenispora, and Oxobacter. The co-culture of these groups with coal significantly changed the coal microbial community composition but did not increase the content of CH4 and H2S. The changed microbial communities mainly belonged to phyla Firmicutes, Proteobacteria, and Actinobacteriota, and increased the relative abundance of genera Bacillus, Thermicanus, Hydrogenispora, Oxobacter, Lutispora, Anaerovorax, Desulfurispora, Ruminiclostridium, and Fonticella. From the microscopic structure of coal, an increase in the number of holes and roughness on the surface of the coal was found but the change of surface functional groups was weak. In addition, the addition of S-related microbial communities increased the contents of phoxim, methylthiobenzoylglycine and glibornuride M5 in aromatic compounds, as well as the content of lauryl hydrogen sulfate in alkyl compounds. Furthermore, the dibenzothiophene degradation-related microbial communities included Bacillus, Brevibacillus, Brevundimonas, Burkholderia-Caballeronia-Paraburkholderia, and Thermicanus, which can break C-S bonds or disrupt benzene rings to degrade dibenzothiophene. In conclusion, the S-related microbial communities in biogas liquid could rebuild the coal microbial community and be involved in the conversion process of organic sulfur in coal.

Vaporization in Liquid-Core Nuclear Thermal Rockets

This work provides an overview of vaporization phenomena in liquid-core nuclear thermal rockets to aid in unifying modeling assumptions by characterizing the impact of vaporization. Historical variations in vapor modeling have led to reported specific impulses ranging from 1000 to 2000s following model refinements in the 1960s and the omission of vaporization consideration post 1990. The only preexisting vapor transport study to not rely on the Reynold’s analogy was performed for the radiator design. This paper performs the first such analysis for the bubbler design, given its renewed interest. Consideration is given to potential centrifugal species separation, proposed fuel mixtures, interplay between chamber pressure and vaporization, impacts on propellant thermoproperties, evaporative cooling, power requirements for vapor separation, and the complexity of hydrocarbon interactions under the proposed chamber conditions. The bubbler design is shown to be well approximated as fully saturated, whereas the radiator and droplet designs may be configured to reduce vaporization to 20% saturation. Characterization of vaporization within liquid cores is essential to early design decisions, such as overall archetype, defining the operating point, and liquid media composition. For a threshold temperature corresponding to around 10% of the propellant being vapor by mass, further increases in temperature begin reducing the specific impulse. Below this threshold temperature, the impact of vaporization on thermal modeling with the chamber is likely negligible. Above this threshold temperature, higher-fidelity thermal modeling will be required, and the work required to separate the vapor begins exceeding 100 kW/(kgH/s). Nozzle kinetics are applied to liquid cores for the first time, showing that specific impulses increase with increasing chamber pressure contrary to historical findings. Historically, modeled uranium-zirconium-carbon mixtures are predicted to reach a specific impulse up to 1260 s. A uranium-tungsten-carbon fuel mixture yielded the best theoretical specific impulse of slightly under 1400 s; however, no nucleonic or thermal analysis has been conducted with this fuel composition.

Enhanced energy transfer via surface plasmons in ternary liquid systems of coumarin-151, ethanol, and benzaldehyde

This investigation explores the plasmonic effect on molecular fluorescence within ternary liquid systems comprising 7-amino-4-(trifluoromethyl) coumarin (C-151) laser dye, ethanol, and benzaldehyde. A key aspect of our investigation involves examining ZrN nanosphere and ZrN nanoshell within these mixtures, marking the first instance of such an analysis in ZrN and ternary liquid compositions. Utilizing experimentally obtained refractive indices, we evaluate resonance peaks in the spectra and their shifts. Our findings reveal improved fluorescence characteristics in C-151 laser dye with the addition of ZrN nanoparticles. Theoretical results suggest that plasmonic nanoparticles play a significant role in enhancing dye fluorescence. These findings deepen our understanding of plasmonics in complex liquid environments and highlight ZrN's potential as an effective alternative plasmonic material for efficient molecular energy transfer at the nanoscale.

Electrofluids with Tailored Rheoelectrical Properties: Liquid Composites with Tunable Network Structures as Stretchable Conductors.

Flexible and stretchable electronics require both sensing elements and stretching-insensitive electrical connections. Conductive polymer composites and liquid metals are highly deformable but change their conductivity upon elongation and/or contain rare metals. Solid conductive composites are limited in mechanoelectrical properties and are often combined with macroscopic Kirigami structures, but their use is limited by geometrical restraints. Here, we introduce "Electrofluids", concentrated conductive particle suspensions with transient particle contacts that flow under shear that bridge the gap between classic solid composites and liquid metals. We show how Carbon Black (CB) forms large agglomerates when using incompatible solvents that reduce the electrical percolation threshold by 1 order of magnitude compared to more compatible solvents, where CB is well-dispersed. We analyze the correlation between stiffness and electrical conductivity to create a figure of merit of first electrofluids. Sealed elastomeric tubes containing different types of electrofluids were characterized under uniaxial tensile strain, and their electrical resistance was monitored. We found a dependency of the piezoresistivity with the solvent compatibility. Electrofluids enable the rational design of sustainable soft electronics components by simple solvent choice and can be used both as sensor and electrode materials, as we demonstrate.

Liquid-liquid equilibrium of the 1-butyl-3-methylimidazolium-based ionic liquids + sodium citrate + water systems at 298.15 K

Liquid-liquid extraction has long been the preferred option for process engineers to develop separation processes and it is used to separate and purify various biological products, metallic ions, colorants, pharmaceutical molecules, and small organic species. Ionic liquids (ILs) are special ecological solvents that can be used as possible substitutes for traditional organic solvents used for extraction and separation processes, becoming them more sustainable and safer. In combination with salts or inorganic polymers, they can form a liquid system of two phases, advantageous due to its wide polarity and viscosity. In this scenario, liquid–liquid equilibrium (LLE) data and phase diagrams for new aqueous two-phase systems containing ionic liquid ([BMIM][OH], [BMIM][Cl], [BMIM][Br]) (1) + sodium citrate (2) + water (3) were determined experimentally at 298.15 K. The ionic liquids were synthesized and characterized in the first part of the study. COSMO-RS was used as a tool to calculate polarity graphs of study molecules. In the second part, liquid–liquid equilibrium was studied using experimental measurements of the binodal curve and tie-lines, testing the quality of experimental data by mass balance, thermodynamic modeling using the NRTL model to correlate liquid–liquid equilibrium data and to do their phase stability. The accuracy of the model data results was verified by Gibbs energy topological mixing surface analysis and σ profiles. The experimental results indicated that the studied systems had type I liquid–liquid phase behavior. It was demonstrated that the ionic liquid [BMIM][OH] demonstrated better behavior to form Aqueous Two-Phase Systems mixed with sodium citrate and water. The results obtained by the thermodynamic modeling and stability with NRTL model weren’t satisfactory, because, besides the low deviations for the liquid phases compositions, the majority of calculated tie-lines was not tangent with the Gibbs surface, showing the limitations of the model for systems with electrolytes.