Binary Mixture System Research Articles

Python-Based Algorithm for Estimating NRTL Model Parameters with UNIFAC Model Simulation Results.

A major challenge in bioprocess simulation is the lack of physical and chemical property databases for biochemicals. A Python-based algorithm was developed for estimating the nonrandom two-liquid (NRTL) model parameters of aqueous binary systems in a straightforward manner from simplified molecular-input line-entry specification (SMILES) strings of substances in a system. This algorithm conducts a series of procedures: (1) fragmentation of the molecules into functional groups from SMILES, (2) calculation of activity coefficients under predetermined temperature and mole fraction conditions by employing universal quasi-chemical functional group activity coefficient (UNIFAC) model, and (3) regression of NRTL model parameters by employing UNIFAC model simulation results in the differential evolution algorithm (DEA) and Nelder-Mead method (NMM). The algorithm was applied to aqueous, binary mixture systems composed of 37 common biochemical substances such as amino acids, organic acids, and sugars. The obtained NRTL parameters were compared with those from Aspen Plus, a commercial software, which has an equivalent function for estimating the NRTL parameters. The percentage mean absolute residuals of the activity coefficients obtained using DEA, NMM, and the parameter estimation tool in Aspen Plus were in the ranges of 0.05-16.69, 0.05-16.69, and 0.09-326.77%, respectively. This in-house algorithm will be helpful for obtaining more accurate NRTL parameters in a timely manner and will facilitate the simulation of biochemical processes for process optimization, energy consumption estimation, and life cycle assessment.

Evaluation of the combined toxicity of compound pollutants of azole fungicides to Raphidocelis subcapitata

In order to investigate the combined toxicity of compound contaminated azole fungicides on alage. Systematic investigation of Difenoconazole, Penconazole, Metconazole, Tetraconazole, Flutriafol, Fuberidazole, Triflumizole, Terrazole, HyMexazol, 9 azole fungicides as the components of the mixture. Thirty-five binary mixture systems with 173 mixture rays were designed by direct equipartition ray method. The growth inhibition toxicity of binary mixtures to Raphidocelis subcapitata was determined by 96-well microplates. Toxic interactions were qualitatively analyzed by Concentration addition (CA) and Independent Action (IA) models. Model Deviation Ratio (MDR) was used to quantitatively evaluate the toxic interaction of binary mixtures of azole fungicides, as well as the equivalent graph method, Toxic Unit (TU) method, additivity Index method (AI), Toxicity Index (MTI) and Combination Index (CI) methods were used to analyze the combined toxicity and toxic interaction of the mixture. The results showed that the frequency of synergistic effect was higher when mixed with Difenoconazole, Penconazole and Triflumizole, and the binary mixing with Flutriafol, Fuberidazole and Metconazole could reduce the toxicity of the mixture, showing additive and antagonistic effects. The toxicity of the mixture ranged from 3.053 to 6.415. In addition, at ambient concentrations, the mixture interaction is dominated by addition.

Effect of water on the excess properties of eutectic solvents

Three eutectic solvents were created utilizing a heating and stirring process. The solvents consist of tetrabutylammonium bromide and levulinic acid, as well as tetrabutylammonium chloride with either levulinic acid or lactic acid. The characterization of the samples was conducted using 1H NMR and IR techniques. The density and viscosity of three different low eutectic solvent and water binary mixture systems were determined within the temperature range of 293.15 to 333.15 K. The volume properties (excess molar volume, coefficient of expansion, coefficient of excess expansion) of the binary mixtures with different amounts of water were thoroughly investigated across the complete range of mole fraction. The study also investigated the impact of viscosity parameters, such as viscosity deviation and Excess activation Gibbs free energy of viscous flow. Furthermore, an analysis was conducted on the interaction between the eutectic solvent and the solvent molecules in the binary mixture. This analysis revealed the presence of hydrogen bonds between the eutectic solvent and water molecules. Moreover, it was confirmed that the excess properties could be fitted with the Redlich-Kister equation with r2 ≥ 0.99,demonstrating high suitability for binary mixes consisting of low eutectic solvents and water.

Induced blue phase and twist grain boundary phase in binary mixtures of chiral calamitic and achiral hockey stick-shaped liquid crystals

Frustrated phases in chiral liquid crystalline systems, such as the blue phase (BP) and the twist grain boundary (TGB) phase, can create new opportunities in liquid crystal research. These frustrated phases have unique optical properties which can be used for specific applications. A new binary mixture system composed of a chiral rod-like ferroelectric liquid crystal and an achiral hockey stick-shaped compound was designed. This binary system exhibits induced frustration, resulting in the emergence of the BP-III and TGB*A phases in addition to the chiral ferroelectric Smectic-C* phase. We report a comprehensive study on several binary mixtures (xH-22.5= 0.162, 0.25, 0.396, 0.562) designed of a chiral ferroelectric liquid crystal derived from the lactic acid, namely 4-(octyloxy)phenyl 3-methoxy-4-((4-((2-(pentyloxy)­propanoyl)­oxy)benzoyl)oxybenzoate and achiral hockey stick-shaped compound, namely (E)-4-((E-((3-(decyloxy)-2-methylphenyl)imino)methyl)-phenyl 3-(4-(dodecyloxy)phenyl)acrylate. These mixtures induced the blue phase (BP-III, ~2.5–6.2K) and the twist grain boundary Smectic-A*phase (TGB*A  ~1.8–6K). Polarizing optical microscopy, birefringence, and dielectric spectroscopy were employed to investigate the BP-III and  phases, as those techniques provide insights into their structural and dynamic properties. The ferroelectric behaviour of the SmC* mesophase was investigated by electro-optics. The obtained results are discussed in relation to the molecular structures of the used materials.

Study of molecular interaction between benzaldehyde and methanol using microwave dielectric relaxation spectroscopy and radial distribution function

A microwave dielectric relaxation study was conducted for mixtures of benzaldehyde (BZ) and methanol (MeOH) over a frequency range of 200 MHz to 20 GHz at seven different temperatures, ranging from 293.15 K to 323.15 K. The dielectric relaxation parameters, obtained through a fitting process, were used to examine their dependence on concentration and temperature. Thermodynamic parameters, such as Gibbs free energy (ΔG), molar enthalpy of activation (ΔH), and molar entropy of activation (ΔS), were evaluated using the temperature dependence of the dipolar relaxation time. The study provided valuable insights into the molecular interactions and dynamic behavior of the components in the binary mixture system. Additionally, a molecular dynamics (MD) simulation study was conducted on the binary mixture of BZ and MeOH to determine the Radial Distribution Function (RDF) and coordination number for different pairs of molecules and atoms, which revealed information about the binding and arrangement of the local structure.

Porous nanofiber/microparticles-structured membrane of polymyxin B modified poly(styrene-random-glycidyl methacrylate) by electrospray for endotoxin removal in blood purification

Inspired by the kidney's renal glomerulus, a binary solvent mixture system of tetrahydrofuran (THF) and methanol was used to form porous nanofiber/microparticles (PNfMp) during electrospray technology. Poly(styrene-random-glycidyl methacrylate) (PSGM) was synthesized by atom-transfer radical polymerization as a supporting material for the electrospray process. During the electrospray process, THF, with a lower boiling point, evaporated first, forming the PNfMp of PSGM containing the nanoemulsified methanol with a higher boiling point. After the solidification of the PSGM, the nanoemulsified methanol evaporated, creating highly porous microparticles/nanofibers of PSGM. The Brunauer-Emmett-Teller (BET) surface area of the PNfMp-structured PSGM membranes reached 986.6 m2/g. We further investigated modifying the surfaces of the electrospun membranes with polymyxin B (PMB) through the epoxy groups of PSGM for endotoxin adsorption. The maximum adsorption capacity of endotoxin on the PMB-modified PSGM membrane with a PNfMp structure is approximately 3.1 EU/mg, which is much higher than that without a PNfMp structure, at 0.7 EU/mg. A filter packed with the PMB-modified PSGM membrane was constructed to remove endotoxin from human plasma. The removal efficiency reaches almost 100 % for 14 mL using 3.2 mg of the membrane at a flow rate of 1 mL/min. Our proposed method provides an ideal strategy to prepare PNfMp membranes for endotoxin removal in blood purification.

Optical assembly of multi-particle arrays by opto-hydrodynamic binding of microparticles close to a one-dimensional chain of magnetic microparticles.

Two-dimensional materials possess a large number of interesting and important properties. Various methods have been developed to assemble two-dimensional aggregates. Assembly of colloidal particles can be achieved with laser-heating-induced thermal convective flow. In this paper, an opto-hydrodynamic binding method is proposed to assemble colloidal particles dispersed in a solution into multilayer structures. First, we use polystyrene (PS) microspheres to study the feasibility and characteristics of the assembly method. PS microspheres and monodispersed magnetic silica microspheres (SLEs) are dispersed in a solution to form a binary mixture system. Under the action of an external uniform magnetic field, SLEs in the solution form chains. An SLE chain is heated by a laser beam. Due to the photothermal effect, the SLE chain is heated to produce a thermal gradient, resulting in thermal convection. The thermal convection drives the PS beads to move toward the heated SLE chain and finally stably assemble into multilayer aggregates on both sides of the SLE chain. The laser power affects the speed and result of the assembly. When the laser power is constant, the degree of constraint of the PS microbeads in different layers is also different. At the same time, this method can also assemble the biological cells, and the spacing of different layers of cells can be changed by changing the electrolyte concentration of the solution. Our work provides an approach to assembling colloidal particles and cells, which has a potential application in the analysis of the collective dynamics of microparticles and microbes.

Sweetness interaction between a novel glycosylated rebaudioside A and various sweeteners in a binary mixture system.

The present study investigated the sweetness interaction and the sensory characteristics of a novel glycosylated rebaudioside A (g-reb_A) when mixed with other sweeteners. Binary sweetener mixtures were formulated by mixing g-reb_A with four types of sweeteners (sucrose, aspartame, acesulfame-K, saccharin). The sweetness potencies of sweeteners were measured at various concentrations. G-reb_A was mixed with each of the four other sweeteners at the concentration ratio of 35:65 or 50:50 to match the sweetness of a 10% sucrose solution. A generic descriptive analysis was conducted to evaluate the binary samples compared to the 10% sucrose solution. Most binary mixtures exhibited an additive effect on sweetness. A marginal sweetness synergistic effect was observed when g-reb_A was mixed with sucrose at the 50:50 ratio. The sensory characteristics of the binary mixture depended on the type of sweetener mixed with g-reb_A. Mixtures of g-reb_Aacesulfame-K or g-reb_Asaccharin elicited significantly higher bitter taste than the other binary mixtures.

Combined toxicity and adverse outcome pathways of common pesticides on Chlorella pyrenoidosa.

Pesticides due to their extensive use have entered the soil and water environment through various pathways, causing great harm to the environment. Herbicides and insecticides are common pesticides with long-term biological toxicity and bioaccumulation, which can harm the human body. The concept of the adverse outcome pathway (AOP) involves systematically analyzing the response levels of chemical mixtures to health-related indicators at the molecular and cellular levels. The AOP correlates the structures of chemical pollutants, toxic molecular initiation events and adverse outcomes of biological toxicity, providing a new model for toxicity testing, prediction, and evaluation of pollutants. Therefore, typical pesticides including diquat (DIQ), cyanazine (CYA), dipterex (DIP), propoxur (PRO), and oxamyl (OXA) were selected as research objects to explore the combined toxicity of typical pesticides on Chlorella pyrenoidosa (C. pyrenoidosa) and their adverse outcome pathways (AOPs). The mixture systems of pesticides were designed by the direct equipartition ray (EquRay) method and uniform design ray (UD-Ray) method. The toxic effects of single pesticides and their mixtures were systematically investigated by the time-dependent microplate toxicity analysis (t-MTA) method. The interactions of their mixtures were analyzed by the concentration addition model (CA) and the deviation from the CA model (dCA). The toxicity data showed a good concentration-effect relationship; the toxicities of five pesticides were different and the order was CYA > DIQ > OXA > PRO > DIP. Binary, ternary and quaternary mixture systems exhibited antagonism, while quinary mixture systems exhibited an additive effect. The AOP of pesticides showed that an excessive accumulation of peroxide in green algae cells led to a decline in stress resistance, inhibition of the synthesis of chlorophyll and protein in algal cells, destruction of the cellular structure, and eventually led to algal cell death.

Radial mixing and segregation of binary density ellipsoids in a rotating drum

In this paper, the Discrete Element Method (DEM) is applied to investigate the radial mixing and segregation of a binary mixture of ellipsoids with different densities in a rotating drum. The ellipsoidal particles are constructed with multi-sphere model, and the periodic boundary condition is adopted. The influences of aspect ratio and density ratio on the mixing quality and final segregation extent are examined. Simulation results show that, light particles are inclined to occupy at the periphery of the granular bed, whereas heavy ones concentrate in the center area. As particle aspect ratio deviates from unity, i.e. oblate or prolate shape, the mixing index is increased and final segregation degree is decreased. It is discovered that convective mixing is predominant over diffusion for any given particle shape (oblate, spherical, prolate). The prolate particles (AR=4.0) reveal the highest compactness of a binary mixture system in the rotating drum. Particle translation is the main movement mode and ellipsoids are more easily to rotate. Particle shape affects collision probability and strength, and ellipsoidal particles need more energy to be driven. The reduction of density ratio of light to heavy particles does inevitably contribute to a greater segregation degree. The results also indicate that the initial states of binary mixtures do not affect the final segregation patterns.

The Microstructure, Rheological Characteristics, and Digestibility Properties of Binary or Ternary Mixture Systems of Gelatinized Potato Starch/Milk Protein/Soybean Oil during the In Vitro Digestion Process.

The in vitro digestibility of potato starch-based foods interacting with milk protein and soybean oil was investigated. Microstructures and rheological changes upon digestion were determined. The results showed that the addition of milk proteins (casein and whey protein) promoted gelatinized potato starch digestion, while soybean oil slowed down gelatinized potato starch digestion. A mixture of soybean oil and milk protein promoted the digestion of milk protein, while a mixture of gelatinized potato starch and milk protein inhibited the digestion of milk protein. The mixture of milk protein and/or gelatinized potato starch with soybean oil promoted the release of free fatty acids in soybean oil. The highest release rate of free fatty acids was attained by a mix of milk protein and soybean oil. The mixed samples were digested and observed with a confocal laser scanning microscope. The viscosity of the digestates was determined by a rheometer. Overall, the results demonstrated that the addition of milk protein and soybean oil had an effect on the in vitro digestibility of gelatinized potato starch and its microstructure.

Response to an applied electric field in an antiferroelectric 1/2 subphase: The role of thermal fluctuations.

The response to an applied electric field in the q_{T}=1/2 subphase of the MC881-MC452 binary mixture system is studied by using thick homeotropically aligned cells. In the ordinary antiferroelectric SmC_{A}^{*} and 1/2 (sub)phases, some nonplanar asymmetric distortions in the antiferroelectric unit cell structure produce induced polarization in the applied field direction, starts to unwind the helix from the beginning, and tends to align the averaged tilt plane direction parallel to the applied field. In the 1/2 subphase under consideration, however, the helix resists being deformed at the beginning and then the thresholdlike steep increase of birefringence Δn occurs in the transition from 1/2 to unwound SmC^{*} at a field of less than 0.5V/µm; we conclude that the thermal fluctuations play an important role in promoting the director flip-flopping in a single layer under the applied field and bring about additional induced polarization, which counteracts the aforementioned ordinary induced one and prevents the helix from unwinding. This suggests that the Langevin-like director reorientation is the mechanism of the V-shaped switching which was actually observed in the thin films of Mitsui mixture [Phys. Rev. Lett. 87, 015701 (2001)0031-900710.1103/PhysRevLett.87.015701] and must have been used in prototyped thresholdless antiferroelectric liquid-crystal displays.

Energy decay of a mixture with local viscoelasticity

We consider a binary mixture system with local Kelvin–Voigt damping in one of the components of the mixture. The well‐posedness and the polynomial stability are proved by the semigroup theory and the frequency domain approach.

An opto-thermal approach for assembling yeast cells by laser heating of a trapped light absorbing particle.

Cell assembly has important applications in biomedical research, which can be achieved with laser-heating induced thermal convective flow. In this paper, an opto-thermal approach is developed to assemble the yeast cells dispersed in solution. At first, polystyrene (PS) microbeads are used instead of cells to explore the method of microparticle assembly. The PS microbeads and light absorbing particles (APs) are dispersed in solution and form a binary mixture system. Optical tweezers are used to trap an AP at the substrate glass of the sample cell. Due to the optothermal effect, the trapped AP is heated and a thermal gradient is generated, which induces a thermal convective flow. The convective flow drives the microbeads moving toward and assembling around the trapped AP. Then, the method is used to assemble the yeast cells. The results show that the initial concentration ratio of yeast cells to APs affects the eventual assembly pattern. The binary microparticles with different initial concentration ratios assemble into aggregates with different area ratios. The experiment and simulation results show that the dominant factor in the area ratio of yeast cells in the binary aggregate is the velocity ratio of the yeast cells to the APs. Our work provides an approach to assemble the cells, which has a potential application in the analysis of microbes.

How do different arsenic species affect the joint toxicity of perfluorooctanoic acid and arsenic to earthworm Eisenia fetida: A multi-biomarker approach

Perfluorooctanoic acid (PFOA) and arsenic are widely distributed pollutants and can coexist in the environment. However, no study has been reported about the effects of different arsenic species on the joint toxicity of arsenic and PFOA to soil invertebrates. In this study, four arsenic species were selected, including arsenite (As(III)), arsenate (As(V)), monomethylarsonate (MMA), and dimethylarsinate (DMA). Earthworms Eisenia fetida were exposed to soils spiked with sublethal concentrations of PFOA, different arsenic species, and their binary mixtures for 56 days. The bioaccumulation and biotransformation of pollutants, as well as eight biomarkers in organisms, were assayed. The results indicated that the coexistence of PFOA and different arsenic species in soils could enhance the bioavailability of arsenic species while reducing the bioavailability of PFOA, and inhibit the arsenic biotransformation process in earthworms. Responses of most biomarkers in joint treatments of PFOA and As(III)/As(V) showed more significant variations compared with those in single treatments, indicating higher toxicity to the earthworms. The Integrated Biomarker Response (IBR) index was used to integrate the multi-biomarker responses, and the results also exhibited enhanced toxic effects in combined treatments of inorganic arsenic and PFOA. In comparison, both the biomarker variations and IBR values were lower in joint treatments of PFOA and MMA/DMA. Then the toxic interactions in the binary mixture systems were characterized by using a combined method of IBR and Effect Addition Index. The results revealed that the toxic interactions of the PFOA/arsenic mixture in earthworms depended on the different species of arsenic. The combined exposure of PFOA with inorganic arsenic led to a synergistic interaction, while that with organic arsenic resulted in an antagonistic response. Overall, this study provides new insights into the assessment of the joint toxicity of perfluoroalkyl substances and arsenic in soil ecosystems.

Solid-liquid transition induced by rigidity disparity in a binary mixture of cell tissues.

The two-dimensional melting of a binary mixture of cell tissues is numerically investigated in the presence of rigidity disparity. We present the full melting phase diagrams of the system by using the Voronoi-based cellular model. It is found that the enhancement of rigidity disparity can induce a solid-liquid transition at both zero temperature and finite temperature. (i) In the case of zero temperature, the system undergoes a continuous solid-hexatic transition followed by a continuous hexatic-liquid transition for zero rigidity disparity, but a discontinuous hexatic-liquid transition for finite rigidity disparity. Remarkably, the solid-hexatic transitions always arise when the soft cells reach the rigidity transition point of monodisperse systems. (ii) In the case of finite temperature, the melting occurs via a continuous solid-hexatic transition followed by a discontinuous hexatic-liquid transition. Our study may contribute to the understanding of solid-liquid transitions in binary mixture systems with rigidity disparity.

Attractors for partially damped systems of binary mixtures of solids

This paper targets the long-time dynamics of a semilinear system modeling a binary mixture of solids with frictional dissipation mechanism acting only on the elastic equation and subjected to nonlinear source term. The coupling gives new contributions to the theory associated with nonlinear dynamics of partially damped semilinear systems of a binary mixture of solids. Using the quasi-stability methods, we prove the existence of a smooth finite-dimensional global attractor irrespective of the wave speeds of the system. Moreover, we establish the existence of exponential attractors.

Assessing joint toxic effects of arsenate and perfluorooctane sulfonate on earthworm by combining integrated biomarker response and mixture toxicity indices

Arsenic and perfluorooctane sulfonate (PFOS) are widely distributed pollutants in the soil environment and could coexist as mixture, but little studies have been reported about their combined toxicity to terrestrial invertebrates. In the present work, we exposed earthworm Eisenia fetida to sub-lethal levels of arsenate (As(V)), PFOS, and their mixture for 30 days. Multiple biomarker responses and bioaccumulation of the two toxicants in the organisms were analyzed to assess the joint toxicity of As(V) and PFOS. Bioaccumulation analysis results demonstrated that the coexistence of As(V) and PFOS in soil could increase the bioavailability of As(V) while decreasing the bioavailability of PFOS. As the level of exposure increased, significant variations were observed in all of the biomarkers analyzed, indicating growth inhibition and oxidative damage. The multiple biomarker responses were summarized by using the Integrated Biomarker Response (IBR) index, and significant dose–response relationships were found in treatments of As(V), PFOS and As(V)/PFOS mixture. Then the toxic interaction between As(V) and PFOS was assessed by combining IBR and two mixture toxicity indices, Effect Addition Index (EAI) and Concentration Addition Index (CAI). Results showed that the joint toxicity of As(V) and PFOS depended on the exposure concentration of As(V). The combined pollution of PFOS with lower concentration of As(V) led to synergistic interaction at the whole range of effect levels, while that with higher concentration of As(V) resulted in the toxicity interaction changing from antagonism to synergism as the effect level increased. As(V) was the main toxicant that caused adverse effects on earthworm biomarkers and affected the joint toxicity of As(V)/PFOS mixture. This study, for the first time, provides valuable toxicological data for the risk evaluation of combined toxicity of As(V) and PFOS in the soil environment. Moreover, this work indicates that the integration of IBR index and EAI/CAI could be an effective and practical method for the characterization of toxicity interaction within binary mixture systems.

Deep eutectic behavior in binary mixtures of protic ionic liquids

The solid–liquid phase equilibrium of ionic liquids (ILs) is a kind of fundamental data, and the deep eutectic behavior of protic ionic liquids (PILs) is scarcely studied in literature. In this work, four PILs, 1,3-dimethyl-2-imidazolidinone bisulfate ([DMIH][HSO4]), pyridinium bisulfate ([Hpy][HSO4]), 2-methylpyridinium bisulfate ([2-mHpy][HSO4]), and 3-methylpyridinium bisulfate ([3-mHpy][HSO4]), were prepared and six binary mixture systems from these four PILs were used to evaluate the deep eutectic behavior. All six systems were found to have a deep eutectic point in the solid–liquid equilibrium curves, and the largest melting temperature depression is 68.8 K appearing in [DMIH][HSO4]-[Hpy][HSO4]. The eutectic compositions and temperatures were determined, and the solid–liquid equilibrium data of the six binary systems were calculated successfully using the two-suffix Margules equation. The molecular interactions were also investigated using quantum calculations to show the non-ideality in the eutectic systems. Since the deep eutectic behavior is in favor of broadening the liquid window and tuning the physical property of ionic liquids, more binary or ternary eutectic ionic liquids can be prepared as functional materials by just simple mixing. In this sense, the study in this paper helps to elucidate the deep eutectic principle for ILs material design.

A new measurement method for mixing and segregation of binary mixture by combining gas cutting-off method and ECVT

Binary mixture fluidization is an important operation type of fluidized bed. The regularity of mixing and segregation of binary mixture is the key to process research and development. In this paper, a new experimental method for the measurement of mixing and segregation of binary mixture is proposed by combining gas cutting-off method and Electrical Capacitance Volume Tomography (ECVT). While inheriting the advantage of high applicability of gas cutting-off method, this method can be of high spatial resolution with the application of ECVT. This combination can not only obtain detailed particle component distribution information, but also reduce the experimental labor intensity. Based on the measuring principle of ECVT and Maxwell Garnett mixing model, the calibration relationship between voxel value and particle mixing ratio was deduced. An experimental binary mixture system was employed to validate the calibration relationship. The result showed that the calculated calibration curve was in good agreement with the experimental calibration curve, which indicates the rationality and feasibility of the method. On this basis, mixing process of the same particle system was quantitatively characterized and analyzed at a given air flow rate. • A new measurement method for mixing and segregation of binary mixtures was developed. • High resolution of ECVT and high application of gas-cutting method were combined. • Measuring principle was mathematically derived for isotropic binary mixture. • Mixing process of experimental binary particle system was visually studied.