Bottom Phases Research Articles

Kinetics, Kinematics, and Muscle Activity Patterns During Back Squat With Different Contributions of Elastic Resistance.

Performing back squats with elastic bands has been widely used in resistance training. Although research demonstrated greater training effects obtained from adding elastic bands to the back squat, little is known regarding the optimal elastic resistance and how it affects neuromuscular performance. This study aimed to compare the force, velocity, power, and muscle activity during back squats with different contributions of elastic resistance. Thirteen basketball players performed 3 repetitions of the back squat at 85% of 1-repetition maximum across 4 conditions: (1)total load from free weightand (2)20%, (3)30%, and (4)40% of the total load from elastic band and the remaining load from free weight. The eccentric and concentric phases of the back squat were divided into upper, middle, and bottom phases. In the eccentric phase, mean velocity progressively increased with increasing elastic resistance, and muscle activity of the vastus medialis and rectus femoris significantly increased with the largest elastic resistance in the upper phase (P ≤ .036). In the concentric phase, mean power (P ≤ .021) and rate of force development (P ≤ .002) significantly increased with increasing elastic resistance. Furthermore, muscle activity of the vastus lateralis and vastus medialis significantly improved with the largest elastic resistance in the upper phases (P ≤ .021). Velocity, power, rate of force development, and selective muscle activity increased as the elastic resistance increased in different phases during the back-squat exercise.

Enrichment and separation of recombinant adeno-associated virus particles by aqueous two-phase extraction

The adeno-associated virus (AAV) has been widely employed as a popular gene therapy vector. However, current methods for its separation and purification exhibit numerous limitations. In this study, polyethylene glycol (PEG)/salt aqueous two-phase system (ATPS) was utilized as an efficient and environmentally-benign approach to separate AAV. The separation efficiency of AAV particles from other cellular components was investigated using various ATPS compositions. The effects of PEG molecular weight, types of phase-forming salts, and concentrations of different components were tested and compared. The optimal separation conditions were determined to be 17 % (w/w) PEG 600, 16 % (w/w) sodium citrate, and 15 % (w/w) crude cell lysate. The AAV particles were predominantly enriched in the interphase, while the impurities were observed in the top and bottom phases. High AAV recovery (>99 %) and efficient impurity removal (>95 %) were achieved. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and transmission electron microscopy were used to characterize and verify the separated AAV particles. The results indicated that aqueous two-phase extraction possesses a robust capability for the enrichment and separation of AAV particles directly from crude cell lysates, and it shows promising potential for the separation of other viral particles.

Solubility of ciprofloxacin in different solvents at several temperatures: Measurement, correlation, thermodynamics and Hansen solubility parameters

BackgroundCiprofloxacin is a commonly prescribed antibiotic drug whose solubility has not yet been completely studied. In this research, its equilibrium solubility at temperatures from T = (278.15 to 318.15) K in 13 neat solvents, namely, namely: 1,4-dioxane, polyethylene glycol (PEG) 600, PEG400, PEG300, N-methyl-2-pyrrolidone (NMP), PEG200, acetonitrile, N,N-dimethylformamide (DMF), ethanol, dimethyl sulfoxide (DMSO), methanol, ethylene glycol and water, is reported. MethodsFlask shake and UV–vis analysis were used for solubility determinations at different temperatures. Bottom solid phases were analyzed by DSC. Significant findingsMole fraction solubility of ciprofloxacin (x2) increases when temperature arises in all solvents. It varies from x2 = 4.11 · 10–6 in neat water to x2 = 1.55 · 10–3 in neat PEG200 at T = 298.15 K. Solubility behavior was adequately correlated by van't Hoff, van't Hoff-Yaws and Apelblat model. From the variation of solubility with temperature the apparent thermodynamic analysis of dissolution was performed in all the solvents. Total Hildebrand solubility parameter of ciprofloxacin (δ2) was calculated based on groups’ contributions by means of both the Fedors and the Hoftyzer-van Krevelen methods as δ2 = (26.4 and 25.7) MPa1/2, respectively. Otherwise, Hansen solubility parameters and total Hildebrand solubility parameter were also determined by using the Bustamante method from experimental solubility values in 16 neat solvents obtaining δ2 = 25.2 MPa1/2. Finally, KAT-LSER model was also employed to evaluate the role of different intermolecular interactions on the dissolution of ciprofloxacin.

Behaviour‐specific spatiotemporal patterns of habitat use by sea turtles revealed using biologging and supervised machine learning

Abstract Conservation of threatened species and anthropogenic threat mitigation commonly rely on spatially managed areas selected according to habitat preference. Since the impact of threats can be behaviour‐specific, such information could be incorporated into spatial management to improve conservation outcomes. However, collecting spatially explicit behavioural data is challenging. Using multi‐sensor biologging tags containing high‐resolution movement sensors (e.g. accelerometer, magnetometer, GPS) and animal‐borne video cameras, combined with supervised machine learning, we developed a method to automatically detect and geolocate typically ambiguous behaviours for the poorly understood flatback turtle Natator depressus. Subsequently, we evaluated behaviour‐specific spatiotemporal patterns of habitat use. Boosted regression trees successfully identified the presence of foraging and resting in 7074 dives (AUC > 0.9), using dive features representing characteristics of locomotory activity, body posture, and three‐dimensional dive paths validated by ancillary video data. Foraging was characterised by dives with longer duration, variable depth, tortuous bottom phases; resting was characterised by dives with decreased locomotory activity and longer duration bottom phases. Foraging and resting showed minimal spatial segregation based on 50% and 95% utilisation distributions. Expected diel patterns of behaviour‐specific habitat use were superseded by the extreme tides at the near‐shore study site. Turtles rested in areas close to the subtidal and intertidal boundary within larger overlapping foraging areas, allowing efficient access to intertidal food resources upon inundation at high tides when foraging was ~25% more likely. Synthesis and applications. Using supervised machine learning and biologging tools, we show the potential for dynamic spatial management of flatback turtles to mitigate behaviour‐specific threats by prioritising protection of important locations at pertinent times. Although results are a species‐specific response to a super‐tidal environment, our approach can be generalised to a broad range of taxa and study systems, facilitating a conceptual advance in spatial management.

Aqueous two-phase extraction: A non-thermal technique to separate and concentrate betalains from Bougainvillea glabra Choisy bracts

The purple bracts of Bougainvillea glabra Choisy contain betalains that can be used as pigmenting agents. The objective was to evaluate the use of aqueous two-phase extraction systems to separate betalains from B. glabra bracts in order to improve the potential of this species as a source of natural pigments. A binodal phase diagram for the mixture of polyethylene glycol 4000 (PEG 4000) and trisodium citrate (Na3Cit; Na3C6H5O7) was studied to select betalain extraction conditions. The separation and concentration of betalains was evaluated and the feasibility of partitioning into betacyanins and betaxanthins was assessed. Mixtures of Na3Cit and PEG 4000 were prepared with concentrations in the ranges of 3.02–39.69% and 0.28–36.98%, respectively, and formed aqueous biphasic systems, with top phases composed mainly by PEG 4000 and bottom phases composed mainly by Na3Cit. The betalains showed a tendency to migrate towards the top phase, with an average separation yield of 92.41% and a concentration of 176.57 mg/L, while in the bottom phase an average content of 4.53 mg/L was found. Such situation was caused by a salting-out phenomenon and by a non-thermal concentration of compounds given by a reduction of the volume ratio between phases. The partition coefficient varied between 18.95 and 183.4 in betacyanins (Bc) and between 6.85 and 80.0 in betaxanthins (Bx). The Bc/Bx ratio varied between 2.82 and 3.26 in top phases and between 1.26 and 1.45 in bottom phases. The use of aqueous two-phase extraction systems allowed betalains to be separated and concentrated, although only a partial partitioning of Bc and Bx was achieved.

Sperm whale acoustic abundance and dive behaviour in the western North Atlantic

Sperm whales are an ideal species to study using passive acoustic technology because they spend the majority of their time underwater and produce echolocation clicks almost continuously while foraging. Passive acoustic line transect data collected between June and August 2016 were used to estimate a depth-corrected acoustic abundance and study the dive behaviour of foraging sperm whales in the western North Atlantic Ocean. 2D localizations (n = 699) were truncated at a slant range of 6500 m and combined with the multipath arrivals of surface reflected echoes to calculate 3D localizations (n = 274). Distance sampling using depth-corrected perpendicular distances resulted in a 10.5% change in the acoustic abundance estimate (2199 whales, CV = 14.6%) compared to uncorrected slant ranges (1969 whales, CV = 14.1%), and a detection function that was a better fit for the data. Sperm whales exhibited multiple foraging strategies, with bottom phases occurring at depths of 400–800, 800–1200, or > 1200 m, accounting for an average 39.2, 49.5, or 44.9% of the total recorded dive time, respectively. These results suggest that estimating 3D localizations using acoustic line transect data improves acoustic abundance estimation and can be used to answer population level questions about foraging ecology.

Characterisation and separation of infectious bursal disease virus-like particles using aqueous two-phase systems

Infectious bursal disease (IBD) causes considerable economic losses in the commercial poultry industry worldwide. The principal way to control IBD virus (IBDV), the causative agent of IBD, is still through vaccination programs. Virus-like particles (VLPs) are recognised as a safe and potent recombinant vaccine platform. This research work explores the characterisation and separation of infectious bursal disease virus-like particles (IBD-VLPs) from crude feedstock. Various characteristics were studied with high-performance size-exclusion chromatography (HP-SEC), sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS-PAGE) and transmission electron microscopy (TEM) analyses. Subsequently, the separation of IBD-VLPs using polyethylene glycol (PEG)/sodium citrate-based aqueous two-phase systems (ATPSs) was conducted and optimised. Moreover, a scale-up study of the best ATPS constituted of 15% PEG 6000, 11% sodium citrate and 10% crude feedstock was performed to compare the separation performance of IBD-VLPs with and without centrifugation-assisted. The results indicated that the optimised ATPS with centrifugation-assisted for both 5 g and 50 g systems showed good recovery of IBD-VLPs of >97% in the interphase between the PEG-rich top and salt-rich bottom phases. These optimised systems also showed high removal efficiencies of impurities of >95%. The results demonstrated that aqueous two-phase extraction could be a promising technology for efficient VLPs separation.

Selective Separation of Vanillic Acid from Other Lignin-Derived Monomers Using Centrifugal Partition Chromatography: The Effect of pH.

In this work, centrifugal partition chromatography (CPC) assisted by a polyethylene glycol (PEG)/sodium polyacrylate (NaPA) aqueous biphasic system (ABS) was applied in the separation of five lignin-derived monomers (vanillin, vanillic acid, syringaldehyde, acetovanillone, and p-hydroxybenzaldehyde). The influence of the system pH (unbuffered, pH 5, and pH 12) and added electrolytes (inorganic salts or ionic liquids (ILs)) on the compound partition was initially evaluated. The obtained data revealed that ILs induced more adequate partition coefficients (K < 5) than inorganic salts (K > 5) to enable separation performance in CPC, while alkaline conditions (pH 12) demonstrated a positive impact on the partition of vanillic acid. CPC runs, with buffered ABS at pH 12, enabled a selective separation of vanillic acid from other lignin monomers. Under these conditions, a distinct interaction between the top (PEG-rich) and bottom (NaPA-rich) phases of the ABS with the double deprotonated form of vanillic acid is expected when compared to the remaining lignin monomers (single deprotonated). This is an impactful result that shows the pH to be a crucial factor in the separation of lignin monomer compounds by CPC, while only unbuffered systems have been previously studied in the literature. Finally, the recovery of vanillic acid up to 96% purity and further recycling of ABS phase-forming components were approached as a proof of concept through the combination of ultrafiltration and solid-phase extraction steps.

Y-Y microfluidic polymer/salt aqueous two-phase system for optimization of dye extraction: Evaluation of channel geometry

ABSTRACT This study’s main purpose is to investigate the effect of the channel inlet angle on extraction efficiency. Also, the potential of microfluidic polymer/salt aqueous two-phase systems (ATPS) for removing methyl orange (MO) dye has been investigated. The simultaneous influence of independent factors including channel inlet angle, initial dye concentration, flow rate, and pH on the extraction efficiency of MO were investigated. The channel inlet angles of 30°, 60°, and 90° were evaluated. By increasing the inlet angle from 30° to 60°, the extraction efficiency increased from 52.76 to 72.80% at the optimum point. The values obtained at the optimum point were in good agreement with the design equations’ predicted values. At the optimal point, a suitable angle of 60°, an initial concentration of 113.4 mg/L, a flow rate of 1 mL/h, and pH=7 were obtained, which according to the predicted equation, the efficiency reaches 73.27%. In microchannels with a channel inlet angle of 60°, due to having a suitable ratio of top and bottom phases in the outlet of the microchannel and also due to the proper contact of the two phases in the channel inlet (the highest mass transfer section), mass transfer rate and extraction efficiency were increased.

Aqueous three-phase systems formed by poly(vinylpyrrolidone) + poly(ethyleneglycol) + lithium sulfate + water: Phase behavior and partition data

Aqueous three-phase systems (A3PSs) have been used to extract and separate several strategic analytes; however, there are several gaps in the characterization and theoretical principles of this technique. Therefore, an A3PS made up of 10,000 g‧mol−1 of polyvinylpyrrolidone (PVP), 10,000 g‧mol−1 of polyethylene glycol (PEG), lithium sulfate (Li2SO4), and water was characterized in this study. The results revealed that PEG, PVP, and Li2SO4 were concentrated in the top, middle, and bottom phases, respectively, whereas water was the main component in all phases. The three-dimensional coordinates of the phase composition points generated a plane with an area that increased as the difference in the phase compositions increased. The tie-plane area (TPA) decreased as the global composition and temperature decreased, indicating a strong temperature effect. Moreover, at relatively low overall concentrations, a phase inversion behavior between the electrolyte-rich phase and the PVP-rich phase was observed at 308.15 K. HE-4R dye molecules preferentially partitioned to the PVP-rich phase, and this trend increased as the TPA and temperature increased. A similar partition behavior was observed for Cu(II) ions, but they preferred to concentrate in the salt-rich phase. At relatively low overall concentrations, the Cu(II) ions promoted phase inversion at 298.15 K, a phenomenon similar to that observed in the temperature study. Thus, the phase diagram for a new A3PS was obtained, and as far as we know, this is the first work that quantitatively describes the TPA.

Cuvier’s beaked whale foraging dives identified via machine learning using depth and triaxial acceleration

Knowledge of Cuvier’s beaked whale Ziphius cavirostris behavior has expanded through the utilization of animal-borne tags. However, many tag types do not record sound—thus preventing echolocation click detections to identify foraging—or have short deployments that sample a limited range of behaviors. As the quantity of such non-acoustic tag data grows, so too does the need for robust methods of detecting foraging from non-acoustic data. We used 692 dives from 5 sound-recording tags on Cuvier’s beaked whales in southern California, USA, to develop extreme gradient boosting tree models to detect foraging based on 1 Hz depth and 16 Hz triaxial acceleration data. We performed repeated 10-fold cross validation using classification accuracy to tune 500 models with randomly partitioned training and testing datasets. An average of 99.9 and 99.2% of training and testing dataset dives, respectively, were correctly classified across the 500 models. Dives without associated sound recordings (n = 2069 from 7 whales including 4 non-acoustic tags) were classified via a model that maximized training information using dive depth and duration, ascent and descent rates, bottom-phase average vertical speed, and roll circular variance during dive descents and bottom phases. Of all long, deep dives (conventionally assumed to include foraging), 2.4% were classified as non-foraging dives, while 0.3% of short, shallow dives were classified as foraging dives. Results confirm that conventional depth and/or duration classifiers provide reasonable estimates of longer-term foraging patterns. However, additional variables previously listed enhance foraging detections for unusual dives (notably non-foraging deep dives) for southern California Cuvier’s beaked whales.

Unexpectedly deep diving in an albatross

Albatrosses are the iconic aerial wanderers of the oceans, supremely adapted for long-distance dynamic soaring flight. Perhaps because of this they are considered poorly adapted for diving1, in contrast to many smaller shearwater and petrel relatives, despite having amphibious eyes2, and an a priori mass advantage for oxygen-storage tolerance3. Modern biologging studies have largely confirmed this view4,5, casting doubt on earlier observations using capillary tube maximum depth gauges1, which may exaggerate depths, and emphasising albatrosses' reliance on near-surface feeding. Nevertheless, uncertainty about albatross diving remains an important knowledge gap since bycatch in human fisheries (e.g. birds becoming hooked when diving for longline bait fish) is thought to be driving many population declines in this most threatened group of birds6. Here we show, using miniature electronic depth loggers (TDRs), that black-browed albatross, Thalassarche melanophris, can dive to much greater depths (19 m) and for much longer (52 s) than previously thought - three times the maxima previously recorded for this species (6 m and 15 s), and more than twice the maxima reliably recorded previously for any albatross (from 113.7 bird-days of tracking4,5,7). Further evidence that diving may be a significant behavioural adaptation in some albatrosses comes from co-deployed 3-axis accelerometers showing that these deeper dives, which occur in most individuals we tracked, involve active under-water propulsion without detectable initial assistance from momentum, sometimes with bottom phases typical of active prey pursuit. Furthermore, we find (from co-deployed GPS) that diving occurs primarily in the distal portions of long-distance foraging trips, with deeper dives occurring exclusively during daylight or civil twilight, confirming the importance of visual guidance.

Efficient Fractionation of Lipids in a Multiproduct Microalgal Biorefinery by Polymers and Ionic Liquid-Based Aqueous Two-Phase Systems

For a multiproduct microalgal biorefinery, most of the cell components should be extracted and fractionated. This work investigates the fractionation of lipids from other microalgal components (pigments, proteins, carbohydrates) using polymers and IL solutions in aqueous two-phase systems (ATPS). The microalgal lipids poorly migrated to the aqueous phases of ATPS and were recovered (97% of the total fatty acids) in a third phase (interphase) formed between the top and bottom phases. Studies with canola oil and purified phospholipids suggest that the high amount of oil, phospholipids, and other natural emulsifiers present in the microalgae mixed with the high amount of water in the ATPS form an emulsion which is difficult to fractionate. However, a solution of polypropylene glycol 400 (25% w/w) displaced 73% of lipids in an immiscible layer which was easy to recover. When combining this approach with a subsequent ATPS, most of the microalgae biomolecules (lipids, proteins, pigments, carbohydrates) could be fractionated in a three-step mild separation concept.

Zwitterion-Assisted Crystal Growth of 2D Perovskites with Unfavorable Phase Suppression for High-Performance Solar Cells.

Despite two-dimensional (2D) Ruddlesden-Popper-phase layered perovskites (RPLPs) exhibiting excellent environmental stability, most solar cells based on 2D RPLP films are fabricated in a controlled inert atmosphere. Meanwhile, the poor charge transport of 2D RPLP films owing to the unfavorable phase arrangement and defects limits the efficiency of 2D RPLP solar cells. Here, we fabricate high-efficiency 2D RPLP solar cells in ambient air assisted by a zwitterion (ZW) additive. We show that the ZW additive suppresses the formation of the bottom 2D phases (n ≤ 2) and the top 3D-like phases in 2D RPLP films. These 2D phases usually grow parallel to the substrate and act as trap sites that inhibit charge transport in the vertical direction. The 3D-like phases, on the other hand, aggravate the long-term stability due to the intrinsic instability of MA+ cations. With improved phase distribution, crystal orientation, and reduced trap states in 2D RPLP films, efficient charge transport is obtained. Finally, a record-high open-circuit voltage (Voc) of 1.19 V and a power conversion efficiency of 17.04% with an enhanced stability are achieved for (BA0.9PEA0.1)2MA3Pb4I13-based (n = 4) solar cells fabricated under high humidity (∼65% RH).

Rheological Properties of Aged Crude Hard Wood Pyrolysis Oil

Upon storage of the pyrolysis oil, aging reactions may initiate phase separation and change of the rheological properties. These changes lead to unfavourable fuel characteristics in handling, transportation and applications. Efforts have been made for alleviation including methods on how to avoid these aging effects and development of equipment capable of handling aged pyrolysis liquids with unfavourable fuel characteristics. Therefore, the aim of this study was to explore the rheological properties of phase separated pyrolysis liquid fuel. Two batches of a well – stored poplar wood pyrolysis oils were used for the investigation; one batch was diluted with water to represent the oils undergoing severe phase separation (forced phase separation), and another batch was not diluted. Steady and dynamic rheological tests were conducted at various temperatures. Homogeneous (whole oil) and the bottom phases of pyrolysis oils were used. Results revealed that the whole oils of both diluted and undiluted oils exhibited low viscosity Newtonian behaviours at higher temperatures and high viscosity non-Newtonian behaviours at low temperatures. The bottom phases of both diluted and undiluted oils exhibited nonNewtonian behaviours with significant higher viscosity than the whole oils. The strain and frequency sweep dynamic tests showed existence of weak structures in the whole oils and strong network structures in the bottom phases. This study suggests that the handling, transportation and application of the pyrolysis oils undergoing phase separation are possible when the oils are treated with higher temperatures predominantly in turbulent state.

Recovery of roseoflavin from a recombinant Streptomyces davaonensis strain by using biphasic aqueous systems

AbstractBACKGROUNDRoseoflavin (RoS) is a naturally occurring red color riboflavin analog compound, produced mainly by Streptomyces davaonensis, with a rising profile owing to its antibacterial potential. However, there is a lack of strategies for its downstream processing and the existing ones are limited to chromatographic techniques involving harmful reagents. The use of aqueous two‐phase systems (ATPS), a liquid–liquid extraction method, is explored in this work as an alternative strategy to recover and purify RoS from S. davaonensis cultures.RESULTSPolymer‐phosphate, alcohol‐phosphate and ionic liquid (IL)‐phosphate systems that varied in composition were tested, where polyethylene glycol (PEG), ethanol (EtOH) and 1‐ethyl‐3‐methylimidazolium acetate ([C2mim] [OAC]) represent the top phases, and phosphate the bottom phase. The partition behavior of either RoS alone or with contaminants was evaluated. In both cases, RoS showed a preference for top phase in all the systems tested. When cell‐free cultures were added to the systems, IL‐salt (13% and 30% w/w), EtOH‐phosphate [50% tie‐line length (TLL)] and PEG8000‐phosphate (35% w/w TLL) systems presented the highest RoS recovery (&gt;95%), but separation of RoS and contaminants was not accomplished. The systems that demonstrated separation of RoS and contaminants were the PEG3350‐ and PEG8000‐salt systems, both with a 15% w/w TLL, as RoS and contaminants partitioned to top and bottom phases, respectively.CONCLUSIONThis is the first attempt at using ATPS to recover RoS from S. davaonensis cultures. It has been proven that RoS can be recovered directly from S. davaonensis cultures using biphasic systems. This strategy may represent a greener alternative to chromatographic techniques. © 2021 Society of Chemical Industry (SCI).

Extraction of estrogen hormones from water samples using an aqueous two-phase system: A new approach for sample preparation in the analysis of emerging contaminants

In this study, an environmentally friendly method of extracting steroid hormones, 17α-ethinylestradiol, levonorgestrel, gestodene, cyproterone acetate and estradiol valerate, using an aqueous two-phase system was developed. The aqueous two-phase system was applied as an organic solvent-free liquid–liquid extraction technique for the determination of these compounds by UV–Vis spectrophotometry in environmental samples. The experimental conditions were evaluated through the pH value of the medium (3.00–11.0), the nature of the electrolyte and polymer forming the system, the tie-line length (26.76–62.53% w/w), the temperature (278.15–313.15 K), and the mass ratio between the bottom and top phases of the system (1–5). The recovery efficiency was evaluated using the partition coefficient and the analytical signal of each hormone in the top phase. The study was carried out through univariate and multivariate optimization and, for the first time, interactions of tie-line length, polymer forming the system and temperature were observed, and these directly influenced the partition of hormones in aqueous two-phase system. An overall experimental condition for the recovery of all hormones simultaneously (L35 + Na2SO4 + H2O, at pH = 3.00, tie-line length = 64.06% w/w, temperature = 298.15 K and mass ratio between the bottom and top phases of the system = 5) was determined. Partition coefficients (8.8 ± 0.8) to (4533 ± 48) were obtained for the hormones in samples of drinking water, samples from lake and river water, and filtered water from a water treatment plant. Thereby, the aqueous two-phase system proved to be an innovative and good organic solvent free liquid–liquid extraction of hormones in environmental samples.

Validation of aqueous two-phase extraction method

Nowadays, consumer interest in food with natural ingredients has increased. This need has led to the research of new sources and green extraction methods. Betalains are compounds responsible for giving color to cacti fruits. The aim is to obtain low-sugar betacyanins extracts from jiotilla Escontria chiotilla using aqueous two-phase systems (ATPS) to color food with the extract. The effect of principal parameters of ATPS (Ethyl alcohol- KH2PO4/K2HPO4) as tie-line length (TL;40,50 and 70), phase volume ratios (Vr; 1 and 3) on the partitioning of betacyanins, betaxanthins, total sugars, reducing sugars, and antioxidant activity in the extract was evaluated. The yields were determined from the top and bottom phases of the aforementioned parameters. Multivariate analysis of variance (MANOVA, α = 0.05) showed that TLL and Vr were statistically significant (P < 0.05). The lowest bottom sugar yield (25.78 ± 3.14%) corresponds to TLL = 40, Vr = 3. Under these conditions, the corresponding value for betacyanins yield is 62.98±4.52%. For the first time, the ATPS was used to extract betacyanins from cactus fruit.•Escontria chiotilla, as a biological source, contained a high percent of betalains•Aqueous two-phase systems (ATPS) was statistically optimized•The developed method enriches the valorization of environmentally related plants waste materials

Regime Map and Triple Point in Selective Withdrawal.

Entrainment in selective withdrawal occurs when both the top and bottom phases are withdrawn through a capillary tube oriented perpendicular to a flat gravitationally separated liquid-liquid interface. The tube introduces two distinct features to the conditions for fluid entrainment. First, the ratio of the two phases being withdrawn is affected by the region of influence of the flow upstream of the tube's orifice. Second, a minimum withdrawal flow rate must be reached for entrainment regardless of the distance between the interface and the tube. We show that these phenomena can be understood based on the Reynolds number that governs the external flow field around the capillary tube and the capillary number that regulates the effect of the viscosity and capillarity.

Elucidating mechanism for the extraction of cobalt, nickel, and iron in polymer-electrolyte aqueous biphasic systems with both phases rich in electrolyte

Polymer-electrolyte aqueous biphasic systems (ABS) have emerged as environmentally and economically sustainable alternatives for the extraction of metals. However, mechanisms of the metal extraction in ABS formed by top and bottom phases enriched in electrolyte need the best elucidation. In this context, extraction of Co(II), Fe(III), and Ni(II) into ABS, which comprised a polymer (PEO1500) or a triblock copolymer (L64 or F68) and a thiocyanate salt, was studied without the use of any auxiliary complexing agent. Metal extraction from the salt-rich phase to the macromolecule-rich phase depended on the hydrophobicity and size of the macromolecule, electrolyte structure, and pH. Extraction around 100% of Fe(III) was achieved in all ABS investigated at pH = 3.0, Co(II) was extracted around 97% in all ABS, while Ni(II) extraction was smaller than 64% for all conditions evaluated. The L64 + NH4SCN + H2O ABS, with a tie-line length of 29% (w/w) afforded a separation factor of 120 for the separation of Co(II) and Ni(II) at pH = 3.0 and 303 for the separation of Ni(II) and Fe(III) at pH = 6.0. It is proposed that the total extraction of Co(II) and Fe(III) ions into the macromolecule-rich phase was mainly determined by the charge transfer between the metal-thiocyanate complexes formed in the ABS and the ethylene oxide units of the macromolecules.