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Hemp seed protein isolates (HPI) were used to produce a gel through probiotic fermentation. This study assessed how fermentation time (ranging from 0 to 16 h) affected the physicochemical properties of the HPI gel. The results indicated that gel formation began after 8 h of fermentation, as demonstrated by a pH decrease, an increase in particle size, and the development of aggregation observed through fluorescence and scanning electron microscopy. The gel produced after 16 h of fermentation showed the highest viscosity, storage modulus, and gel strength, attributed to stronger molecular interactions, including non-covalent and covalent crosslinking. However, the gel produced after 12 h of fermentation showed the highest water-holding capacity, and extending the fermentation beyond 12 h caused a decrease in water-holding capacity. Additionally, the subunits tended to form polymers after fermentation, suggesting that gel formation was influenced by both acidification and specific covalent crosslinking. These findings propose that HPI could serve as a viable alternative for developing plant-based gel products. [ABSTRACT FROM AUTHOR]

The present work shows the development of a comprehensive theoretical formulation for its application in the study of the internal flow of pressure-swirl atomizers with helical channels: "screw-conveyer", which are characterized by presenting in their inlet channels, an angle of incidence or helix angle ψ. This angle originates a trigonometric factor ( cos ψ ) that must be considered in the geometrical characteristics parameter of pressure-swirl atomizer ( A h ), which consequently involves other geometric parameters, such as the annular section coefficient (φ), discharge coefficient ( C d ), spray angle ( 2 α ), etc., being relevant in the internal flow study and design of the pressure-swirl atomizers type screw-conveyer. This theoretical formulation integrates an internal ideal flow model (Abramovich theory) with a model that considers the influence of the liquid viscosity (Kliachko theory) and hydraulic resistance of Idelchik. For the validation of this theoretical formulation, numerical simulation was used, considering the commercial software Ansys Fluent 2023 R2 furthermore, hexahedral meshes were generated with the ICEM CFD software 2023, for four cases of helix angle ψ ( 15 ° , 30 ° , 45 ° and 60 ° ), with application of the RNG k- ε turbulence model and VOF multiphase model (volume of fluid) for the location of the liquid-gas interface and spray angle visualization. [ABSTRACT FROM AUTHOR]

A problem has been noted regarding the admixture of fuel to a low viscosity lubricant in hybrid electric vehicles (HEVs). This is very detrimental to the wear and tear of engine operating components. In this study, the operating conditions of HEVs were analysed. Using X-ray fluorescence spectrometry (XRF), engine oils of two different viscosity classes were compared after the operating process and these data were compared with fresh reference samples. Attention was paid to the content of elements such as Ca, Zn, Mo, Sn, Cd, Fe Pb, Si, Cu, and Ni. The depletion of anti-wear additives, as well as the higher content of metallic wear products relative to the operated 5W30 (engine oil), contributed to the overall assessment of the lubricity of the 0W30 oil, as well as to the tribological results. Then, under laboratory conditions, oil samples contaminated with up to 1 to 8% fuel were subjected to rheological (mini AV-X viscometer) and tribological (four-ball tester) tests. The dependence of the local pressure at the metal-to-metal contact point in the kinematic node on viscosity showed the dissimilar nature of the used and fresh oil and the divergence of the domains for the two groups of samples. Increasing the fuel contamination of used oil above 4% drastically reduces the pressure responsible for maintaining the oil film. In order to improve lubricant performance during HEV operation in urban conditions, it was proposed to carry out extra-urban traffic driving in order to evaporate the fuel from the engine oil. A shorter oil change interval is also recommended. [ABSTRACT FROM AUTHOR]

Biosurfactants represent a promising choice for the development of environmentally friendly and gentle personal care cleansers. Building viscosity is one of the major challenges to apply biosurfactants. In this study, sodium lauroyl sarcosinate (LS) and sodium lauroamphoacetate (LA) were used as bases to build wormlike micelles, and subsequently rhamnolipids were introduced to build mild surfactant systems. The LS‐LA mixture had the highest viscosity at the mass ratio of 1:5 and pH 6.0. After adding 1 wt% and less rhamnolipid, relatively high viscosity can be maintained. The viscosity of LS‐LA‐rhamnolipid can be increased by adding NaCl and more significantly by the addition of carrageenan due to its synergistic interactions with the surfactant mixture. In addition, the foaming properties of the systems are characterized with different amounts of rhamnolipid and carrageenan, which are correlated with the bulk viscosity and interfacial elasticity of the diluted solution used for the foaming test. Rhamnolipids have both high mildness and cleaning efficacy and adding rhamnolipids can significantly increase the mildness of the system. This study offers practical solutions for the incorporation of rhamnolipids or other biosurfactants in the formulation of personal care cleansers. [ABSTRACT FROM AUTHOR]

Existing numerical methods for modeling slurry infiltration often employ a fluid continuity equation commonly used in groundwater flow analysis. However, it is essential to account for the changes in fluid density and viscosity due to shifts in slurry concentration. In view of this, a multi-field numerical model is developed to simulate the slurry infiltration in saturated soil considering the coupling relationship between particle transportation, fluid seepage, and soil deformation. The governing equations of slurry infiltration are derived based on the mass conservation law. The permeability coefficient is modified through spatiotemporal variation of slurry viscosity, which is governed by concentration modifications. The calculated results are validated using the existing test data, which rectifies the issue of non-conservation of mass in the existing model based on the continuity condition of the liquid phase. Finally, the method is applied to a model of a slurry trench to simulate the process of slurry infiltration, including the spatiotemporal variation of deposition, fluid pressure, and concentration. The time of mud cake formation is determined based on the pressure–time distribution. It is found that the time of mud cake formation in the slurry trench can be shortened by increasing the slurry concentration. [ABSTRACT FROM AUTHOR]

We offer a modern interpretation of Lagrangian hydrodynamics as employed in Lagrangian simulations of compressible fluid flow. Our main result is to show that artificial viscosity, traditionally viewed as a numerical artifice to control unphysical oscillations in flows with shocks, actually represents a physical process and is necessary to derive accurate simulations in any compressible flow. We begin by reviewing the origins of two numerical devices, artificial viscosity and finite‐volume methods. We proceed to construct a mathematical (PDE) model that incorporates those numerics and in which a new length scale, the observer, arises representing the discretization. Associated with that length scale, there are new inviscid fluxes that are the artificial viscosity as first formulated by Richtmyer and an artificial heat flux postulated by Noh but typically not included in Lagrangian codes. We discuss the connection of our results to bivelocity hydrodynamics. We conclude with some speculation as to the direction of future developments in multidimensional Lagrangian codes as computers get faster and have larger memories. [ABSTRACT FROM AUTHOR]

A series of seven new meso -phenyl BODIPY-pyrrolo[3,4- b ]pyridin-5-one conjugates were synthesized in one experimental step by using a Sc(III)-catalyzed Ugi-Zhu three-component reaction coupled to a cascade sequence (aza Diels-Alder/ N -acylation/aromatization) as post-MCR functionalization process. Further experimental studies were performed behind understanding the fluorescence response toward viscosity. All compounds exhibited a linear response between increasing viscosity (DMSO and glycerol mixtures) and fluorescence intensity. The different substituents also influenced the photophysical properties. Furthermore, in DMSO all compounds exhibited dual emission. Each band is attributed to the pyrrolo[3,4- b ]pyridin-5-one and BODIPY moieties, respectively. The electronic structure of all compounds was computed by DFT and TD-DFT calculations, allowing to determine the molecular orbitals involved in the electronic transitions. [ABSTRACT FROM AUTHOR]

Spray drying is a widely used method for producing food powders in large quantities, but it also has a high energy demand. To address this, researchers have long aimed to increase the solid content of liquid feeds, which poses the challenge of atomizing high-viscosity liquids into fine droplets. The Air-Core-Liquid-Ring (ACLR) nozzle offers a potential solution by inducing an internal annular flow, though it faces its own limitations due to internal flow instabilities. This study investigates how the nozzle flow conditions impact spray performance under different process conditions and liquid viscosities. We found that internal lamella thickness and atomization uniformity vary with pressure, viscosity, and liquid volume flow. Nonetheless, pressure appears to be the real critical factor in that case. The Air-to-Liquid Ratio (ALR) might be more decisive for the droplet size distribution than liquid viscosity. Future research should explore higher viscosities and consider simulations to circumvent experimental limitations. [ABSTRACT FROM AUTHOR]

Applications often expose wormlike micelle solutions to a very wide range of shear and temperature conditions. The two-species model presented in Part I [Salipante et al., J. Rheol. 68 (2024)] describes the nonlinear rheology over a wide range of shear rates. Here, we compare the model predictions to measurements using a combination of microcapillary and rotational rheology to measure the viscosity of surfactant solutions across seven decades of shear rate and five decades of viscosity. The effect of temperature is studied between 20 and 60 ° C for different surfactant concentrations. Model parameters are determined from both small-amplitude shear measurements and fitting to the nonlinear data. Under shear stress, the model predicts due to hindered combination kinetics that the average micelle length decreases from several micrometers to a few hundred nanometers. At sufficiently high stress, the micelle shear rheology exhibits a transition from entangled wormlike behavior to a dilute rod rheology in agreement with the model. Transient stress-growth measurements exhibit a large overshoot, which is rather well predicted by the model with hindered combination rate. Microcapillary flow birefringence also is adequately predicted by the model, confirming the accuracy of its predicted micelle lengths and exhibiting a marked change in stress-optic response at the transition between entangled polymers and dilute rods. The relaxation of retardance after flow cessation follows model predictions that include micelle-micelle interactions, which are sensitive to the rotational diffusivity and length. These methods can be applied broadly to explore relationships between composition and performance. [ABSTRACT FROM AUTHOR]

We develop a rheological model to approximate the nonlinear rheology of wormlike micelles using two constitutive models to represent a structural transition at high shear rates. The model is intended to describe the behavior of semidilute wormlike micellar solutions over a wide range of shear rates whose parameters can be determined mainly from small-amplitude equilibrium measurements. Length evolution equations are incorporated into reactive Rolie-Poly entangled-polymer rheology and dilute reactive-rod rheology, with a kinetic exchange between the two models. Although the micelle length is remarkably reduced during flow, surprisingly, we propose that they are not shortened by stress-enhanced breakage, which remains thermally driven. Instead, we hypothesize that stretching energy introduces a linear potential that decreases the rate of recombination and reduces the mean micelle length. This stress-hindered recombination approach accurately describes transient stress-growth upon start-up shear flow, and it predicts a transition of shear viscosity and alignment response observed at high shear rates. The proposed mechanism applies only when self-recombination occurs frequently. The effect of varying the relative rate of self-recombination on the rheology of wormlike micelles at high shear rates is yet to be explored. [ABSTRACT FROM AUTHOR]

This study theoretically predicted the response of superimposed squeeze and rotational flows (SSRF) of fluids with different viscous behaviors (i.e., Newtonian, shear-thinning, and shear-thickening fluids). The theoretical predictions were verified using the plate-plate geometry for the SSRF measurements with the Newtonian and power-law fluids. In all the cases, the squeeze force increased as the gap decreased, but the response was very different for each rheological behavior. The variation in the squeeze force with the gap was not affected by the superimposed rotational shear stress value, owing to the nondependency of the viscosity on the shear for Newtonian fluids. However, for the power-law fluids, the squeeze force variation with the gap value was based on the value of the superimposed shear stress value. The decrease and increase in the viscosity with the shear stress for the shear-thinning and shear-thickening fluids, respectively, resulted in opposite trends of the squeeze force with the gap value variation. For the shear-thinning fluids, the squeeze force for each gap value decreased with increasing superimposed rotational shear stress. The opposite trend was observed for the shear-thickening fluid. In the absence of wall slip, the theoretical predictions well agreed with the experimental results. [ABSTRACT FROM AUTHOR]

In this work, a framework for deriving theoretical equations for mean squared displacement (MSD) and fractional Fokker–Planck is developed for any arbitrary rheological model. The obtained general results are then specified for different fractional rheological models. To test the novel equations extracted from our framework and bridge the gap between microrheology and fractional rheological models, microrheology of polystyrene in tetrahydrofuran solutions at several polymer concentrations is measured. By comparing the experimental and theoretical MSDs, we find the fractional rheological parameters and demonstrate for the first time that the polymer concentration regimes can be distinguished using the fractional exponent and relaxation time data because of the existence of a distinct behavior in each regime. We suggest simple approximations for the critical overlap concentration and the shear viscosity of viscoelastic liquidlike solutions. This work provides a more sensitive approach for distinguishing different polymer concentration regimes and measuring the critical overlap concentration and shear viscosity of polymeric solutions, which is useful when conventional rheological characterization methods are unreliable due to the volatility and low viscosity of the samples. [ABSTRACT FROM AUTHOR]

In this paper, our main interest is to propose a viscosity iterative method for approximating solutions of variational inequality problems, resolvents of monotone operators and fixed points of ρ-demimetric mappings with multiple output sets in Hadamard spaces. We prove a strong convergence result for approximating the solutions of the aforementioned problems under some mild conditions. Also, we present an application of our main result to a convex minimization problem. Our results improve and generalize many related results in the literature. [ABSTRACT FROM AUTHOR]

With the extensive use of manufactured sand and admixtures, it has been observed that as the shear rate increases, the shear rate–shear stress curve of some fresh wet shotcrete materials increasingly deviates from a linear correlation. It is necessary to study the rheological properties of wet shotcrete using a nonlinear model due to the large error when utilizing the Bingham model to describe the concrete. The torque-velocity curve of wet shotcrete was determined using an ICAR rheometer in this study. The experimental data was fitted using the Bingham model, Herschel-Bulkley (H-B) model, and modified Bingham (M-B) model, resulting in the determination of the associated rheological parameters. The M-B model exhibits the most optimal fitting effect, followed by the H-B model and the Bingham model. As the shear rate reaches a specific value, the M-B model consistently represents a higher degree of divergence from linearity compared to the H-B model. Furthermore, considering the limitations of the H-B model which includes varying dimension parameters, this study enhanced the calculation approach for determining the equivalent plastic viscosity based on Larrard et al.'s (Mat Struct 31:494–498, 1998) research. Ultimately, the impact of the mix parameters on the yield stress and plastic viscosity of the three rheological models was analyzed through the range approach. This study is beneficial for enhancing the comprehension of the rheological characteristics of wet shotcrete. [ABSTRACT FROM AUTHOR]

Electrohydrodynamic atomization (EHDA) has advantages in producing fine uniform droplets with low energy consumption. In this work, the droplets generated by the EHDA under the dripping mode have been captured by a backlit high-speed imaging system under various liquid temperatures T (293–343 K) and electric Bond numbers BoE (0–0.75). The temperature-viscosity relationships of the working fluids (G20, G40, G50, and G66) were fitted by an Arrhenius-type model. The effects of BoE, We, and T on the dimensionless droplet limiting length l* and oscillation frequency f were investigated through extensive experiments. The experimental results show that the droplet limiting length elongated with the higher liquid viscosity. However, the oscillation frequency of the meniscus declines with the liquid viscosity. By the elevation of liquid temperatures, the droplet limiting length diminishes, but the oscillation frequency of the liquid meniscus accelerates. Coefficients to estimate the effects of the flow rate and the temperature on oscillation frequency are introduced into the classical theory of meniscus oscillation to develop a semi-empirical model. The proposed model could estimate oscillation frequency for the meniscus under various electric Bond numbers, Weber numbers, and temperatures. The prediction achieves good agreements with experimental results. [ABSTRACT FROM AUTHOR]

The general recognition of the existence of atoms and molecules occurred only at the beginning of the twentieth century. Many researchers contributed to this, but the ultimate proof of the molecular nature of matter that convinced even the last sceptics was the confirmation of Albert Einstein's statistical-fluctuation theory of Brownian motion, a part of his comprehension of interdisciplinary atomism, by Jean Perrin's experiments on colloidal gamboge particles. Einstein noticed a difference between the values of Avogadro's constant derived from Perrin's experiments and Planck's calculation from black-body radiation. Einstein assumed the incorrectly evaluated size of the gamboge spherules to be a culprit of the difference and asked Perrin to check the assumption with additional experiments and using the viscosity formula introduced in his own dissertation. The result was a discrepancy that neither Einstein nor Perrin settled any further. In this communication, based on the survey of developments in colloid and polymer science and their comparison with relevant experiments, an explanation of the dilemma is given that now, after more than a century, proves Einstein correct. The comparison was de facto possible during his lifetime. [ABSTRACT FROM AUTHOR]

The thermophysical properties (viscosity, density, and surface tension) of the secondary metallurgical slags with various CaO/Al2O3 ratios (0.56–1.99) and SiO2 (1–20 wt%) contents are investigated. The results show that the addition of SiO2 increases the viscosity of the cleanness and desulfurization slags (CaO/Al2O3 ratios ≥1). In slag with a higher Al2O3 content (CaO/Al2O3 < 1) and constant CaO content, the viscosity shows a first decreased and then increased phenomenon with the addition of SiO2. Moreover, the breakpoints of the viscosity are strongly lowered with the addition of SiO2. Both the density and surface tension of slags show a decreasing tendency with the SiO2 addition. Moreover, the single hot thermocouple technique method is applied to investigate the crystallization process of the slags, and the result shows that with high SiO2 contents, glassy layers are formed on the molten slags. [ABSTRACT FROM AUTHOR]

In this study, tetradecyl methacrylate-maleic anhydride-benzylidene acetone (C14MC-MA-MCA) terpolymers were synthesized via free radical polymerization and evaluated as pour point depressants (PPDs) for coal-based diesel. The findings indicate that the C14MC-MA-MCA (3:1:1) terpolymer exhibited the most effective inhibition of the solid point (SP) at 1500 ppm concentration. Specifically, it reduced the SP of coal-based diesel from − 4 to − 42 °C, marking a significant decrease of 38 °C. Furthermore, the crystallization behavior and SP reduction mechanism of C14MC-MA-MCA in coal-based diesel were investigated using viscosity analysis and polarized optical microscopy (POM). [ABSTRACT FROM AUTHOR]

Objective: To evaluate the fracture behavior of human molars with extensive MOD restorations using short‐fiber‐reinforced resin composite of varying viscosities. Materials and Methods: Human molars were randomly divided into seven groups (n = 12): intact teeth (control); restoration using conventional high‐viscosity resin composite without (Filtek Z350XT, 3M) or with fibers (everX Posterior, GC); conventional low‐viscosity resin composite without (Filtek Supreme Flowable, 3M) or with fibers (everX Flow Dentin Shade, GC); bulk‐fill low‐viscosity resin composite (Filtek Bulk Fill Flow, 3M) or with fibers (everX Flow Bulk Shade, GC). Restorations were performed on extensive MOD preparations, following the manufacturers' recommendations for each material. Specimens underwent fracture strength testing (N) and fracture pattern (%) categorized as repairable, possibly repairable, or non‐repairable. Results were analyzed using a generalized linear model (N) and Fisher's exact test (%), with α = 0.05. Results: Restorations performed with high‐viscosity materials showed fracture strength values similar to the control and higher than those of restorations using low‐viscosity resin composites (p < 0.0001), except for the bulk‐fill low‐viscosity resin composite with fibers (p > 0.05). Teeth restored using low‐viscosity resin composite with fibers showed a higher % of repairable and possibly repairable fractures than the control (p = 0.0091). Conclusions: The viscosity of materials mediated the fracture strength, with restorations using high‐viscosity resin composites promoting values similar to the intact tooth; however, the presence of fibers influenced the fracture pattern. Clinical Significance: Teeth with MOD cavities restored with high‐viscosity resin composites showed similar fracture strength to intact teeth. Fiber‐reinforced low‐viscosity resin composite for the base of restoration resulted in a more repairable/possibly repairable fracture pattern. [ABSTRACT FROM AUTHOR]

The resurgence of interest in hybrid joints, combining adhesive bonding with mechanical fastening in engineering applications, is driven by the recognition of unique advantages and limitations inherent in each joining method. Unlike conventional bonded joints with precise adhesive thickness control, hybrid joints involving pre-tensioned bolts depend on a process termed squeeze-flow, influenced by joint geometry, adhesive viscosity, and adhesive filler presence. A method for the precise measurements of the adhesive layer thickness, conducted at 5 mm intervals, proved its accuracy and repeatability. The results revealed the significant impact of adhesive viscosity and filler characteristics on adhesive layer thickness. Viscosity, while playing a central role, is not acting in isolation, as filler properties collectively influence adhesive layer thickness distribution and bonding performance. The complexity of this relationship underscores the interplay between adhesive layer thickness, viscosity, filler content, and load-bearing capacity. Smaller-sized fillers result in thinner layers and reduced load capacities, while adhesives with larger particles exhibit higher load capacities. This complexity emphasizes the need for a nuanced approach when selecting adhesives for specific applications, considering not only viscosity but also filler attributes to optimize bonding performance in hybrid joints. [ABSTRACT FROM AUTHOR]

Fortifying conventional foods with postbiotic powders (PP) is an effective approach for the production of functional products. Preserving both functional properties of PP and the physical characteristics of fortified products is essential during this process. This study aimed to investigate the antioxidant activity and consumer testing of low-fat yoghurt fortified with PP and changes in their physical properties, including rheology, water holding capacity, and microstructure over a 21-day storage period. PP, derived from Bifidobacterium animalis subsp. lactis BB12 grown in cheese whey (CW) and skim milk (SM), was added to the product at 1% individually (B12-CW and B12-SM) and in a mixture (BB12-CW-SM). The results indicated that the antioxidant activity of the samples fortified with PP was 4.6 − 6.3%, almost double the values in samples without PP, despite their similar viability of starters (Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus) (> 8.5 log cfu/g). Adding BB12-CW significantly reduced mouthfeel, flavor, and overall acceptability of the product, while adding BB12-SM and BB12-CW-SM did not alter any consumer acceptability. Similarly, regardless of PP types, their fortification had negligible effects on viscosity, viscoelastic properties, shear-thinning behaviors, water-holding capacity, and microstructure formation, which remained nearly unchanged during storage. Overall, the addition of PP, particularly BB12-SM and BB12-CW-SM, significantly increased antioxidant activity while preserving important physical and consumer acceptance of yoghurt. These findings underscore the potential of postbiotics as functional ingredients, enhancing both the nutritional values and consumer appeal of yoghurt, thereby promoting its health benefits. [ABSTRACT FROM AUTHOR]

Lactose hydrolyzed skim milk powder has the potential to become a staple value-added ingredient in snack and frozen foods because 70% of the population suffers from lactose intolerance. However, the flow behavior of lactose hydrolyzed skim milk concentrates and their resulting products need to be understood. The aim of this study was to compare two rheological modeling methods and determine which method is best for predicting rheological behavior in lactose hydrolyzed and unhydrolyzed skim milk concentrates and reconstituted powder samples. The two methods compared are the combined temperature-concentration multiple-linear regression model and the shear rate-temperature-concentration superposition principle master curve model. Prior to fitting the data to the two models, the effect of temperature was determined via the Arrhenius relationship and the effect of concentration was determined via the Exponential relationship. The combined temperature-concentration method resulted in a single logarithmic model for each concentrate type which yields the consistency coefficient at any temperature and concentration input. The master curve method resulted in a single Power law type model for each concentrate type that describes the overall rheological behavior of the samples. When the predicted consistency coefficients from each method were compared to the raw data, both the master curve (r = 0.973, P < 0.0001) and the combined (r = 0.940, P < 0.0001) methods showed a strong correlation to the raw data. When the results were examined by concentrate type, the master curve model had a stronger fit (P < 0.01) for the reconstituted samples compared to the combined model which did not show a statistically significant correlation to the raw data (P < 0.075). The results of this study indicate that the master curve method is superior for predicting the rheological behavior of concentrated milk samples prepared from varying methods within our tested ranges. [ABSTRACT FROM AUTHOR]

Summary: Tannins, which are known as anti‐nutrient compounds with capability of limiting proteins and minerals bioavailability, are present in Persian gum. Ultrafiltration (UF, polysulfone membrane, 30 and 90 kDa, 1, 2 and 5 bar) and nanofiltration (NF, polysulfone, 400 Da, 2.5 and 5 bar) were used to remove tannin from the soluble fraction of Persian gum. The results revealed that the highest amount of tannin removal was achieved in UF (5 bar) and NF (5 bar). However, the use of the membrane process significantly decreased the apparent viscosity of the permeate, which might have an undesirable effect on the functionality of the gum. The effects of membrane molecular weight cut‐off, feed temperature, ultrasound pre‐treatment, feed concentration and pH, on the amount of tannic acid reduction, and changes in permeate flux, volume concentration factor difference, tannin reduction efficiency, and permeate apparent viscosity were evaluated. The results showed that total tannin removal efficiency was increased by ultrasound pre‐treatment, reduction of feed pH, and higher membrane molecular weight cut‐off. Increasing the feed temperature and concentration enhanced the apparent viscosity of permeate, although its value was lower than the control sample. [ABSTRACT FROM AUTHOR]

The investigation carried out in this study focused on exploring the hydrogen bonding structure of liquid solutions of methyl lactate and 1-alkanols include 1-butanol, 1-pentanol, 1-hexanol, and 1-heptanol. To analyze the interactions between the molecules, the researcher utilized the cubic-plus-association (CPA) model, which takes into account both the physical and association interactions. The maximum deviation observed in the density of the liquid solutions of methyl lactate with 1-heptanol was 0.28%, indicating the effectiveness of the CPA model in accurately modeling the density. Additionally, the researchers calculated the excess molar volumes and deviation in viscosity for the studied liquid mixtures. The analysis of these measurements revealed that the solutions of methyl lactate with 1-alkanols exhibited positive excess molar volumes across the entire concentration range. On the other hand, negative viscosity deviations were observed for the mentioned alkanols. These findings suggest that there are weak intermolecular associations within the liquid solutions, with weaker bond strength observed in higher alkanols. [ABSTRACT FROM AUTHOR]

In this article, we present a formally fourth‐order accurate hybrid‐variable (HV) method for the Euler equations in the context of method of lines. The HV method seeks numerical approximations to both cell averages and nodal solutions and evolves them in time simultaneously; and it is proved in previous work that these methods are supraconvergent, that is, the order of the method is higher than that of the local truncation error. Taking advantage of the supraconvergence, the method is built on a third‐order discrete differential operator, which approximates the first spatial derivative at each grid point using only the information in the two neighboring cells. Analyses of stability, accuracy, and pointwise convergence are conducted in the one‐dimensional case for the linear advection equation; whereas extension to nonlinear systems including the Euler equations is achieved using characteristic decomposition and the incorporation of a residual‐consistent viscosity to capture strong discontinuities. Extensive numerical tests are presented to assess the numerical performance of the method for both 1D and 2D problems. [ABSTRACT FROM AUTHOR]

In order to improve the understanding on static liquefaction phenomenon, this paper presents an insight into the instability mechanism of a silty sand originating from the Sakarya region (Turkey). Monotonic undrained simple shear tests were performed in either strain-controlled or stress-controlled modes. The interpretation of the experimental results allowed us to draw three interesting conclusions on instability conditions: (1) Hill's stability postulate can be conveniently used to identify the onset of instability for strain-controlled tests, whereas in stress-controlled conditions, an alternative new parameter η* (modified apparent viscosity) was introduced. Depending on the strain rate, η* allows to identify stability conditions more clearly than second-order work; (2) the value of the pore pressure ratio at the onset of instability (ru,is), ranging between 0.30 and 0.50, is linearly linked to the state parameter ψ ; and (3) at the onset of instability, the dependence of both the major and minor principal stress directions (αis and βis) and Lode's angle (θis) on ψ was also observed. These findings are expected to be of some help for a more consistent approach to the constitutive modeling of the static instability mechanism. [ABSTRACT FROM AUTHOR]

The corrosion of the alumina‐based refractory in coal slags would increase the Al2O3 contents of the coal slag and the influences of that on coal slag performances need to be further considered. The effects of Al2O3 on viscosities and structures of SiO2‐MgO‐CaO‐Fe2O3‐(10–22 wt%)Al2O3 coal slags were investigated in this work. The viscosity of the coal slag increased first with increasing the content of Al2O3 from 10 wt% to 14 wt% and further declined with the addition of Al2O3 content to 22 wt%. The role of Al2O3 in the present coal slag was identified. Al2O3 mainly behaved as an acidic oxide in coal slags when the Al2O3 content was less than 14 wt%, which polymerized the slag structure and increased the viscosities, and with further addition of Al2O3 to 22 wt%, a part of Al2O3 behaved as network modifiers due to the deficiency of enough metal cations for charge compensation, which could simplify the slag networks and reduce the viscosity. The variations of slag viscosities were consistent with the change tendencies of structures analyzed by spectra techniques. [ABSTRACT FROM AUTHOR]

The present study investigates the influence of the crystal volume content on viscous crack healing in glass ceramic glass sealants. To ensure constant microstructure during healing, soda–lime–magnesium silicate glass matrix composites with varied volume fractions of ZrO2 filler particles were used. Crack healing was studied on radial cracks induced by Vickers indentation, which were stepwise annealed to monitor the healing progress by confocal laser scanning microscopy. Confirming previous studies, healing of radial cracks in pure glass was found delayed by global flow phenomena like crack widening and crack edge and tip rounding to minimize the sample surface. With increasing ZrO2 filler content, these global flow phenomena were progressively inhibited whereas local flow phenomena like sharp crack tip healing could still occur. As a result, crack healing was even accelerated by filler particles up to a maximum filler content of 17 vol% whereas crack healing was fully suppressed only at 33 vol% filler content. [ABSTRACT FROM AUTHOR]

This study optimized the rheological parameters of doughs with partial substitution of wheat flour for blends of whole grain flours from germinated Andean pseudocereals such as quinoa (GQF), kiwicha (GKF), and cañihua (GCF) for bread production. The optimization was conducted through a Simplex-Centroid Mixture Design (SCMD) and Desirability Function (DF). Experiments were formulated using 80 to 90% wheat flour and 5 to 15% germinated pseudocereal blends. The rheological evaluation included farinograph, extensograph, and amylography analyses. Results showed that whole flour from germinated pseudocereals increases the water absorption, consistency, and extensibility of the doughs; and decreases its development time, stability, resistance to extensibility, temperature, and peak viscosity. The GQF-GKF blend developed more extensible and stable doughs, while GCF increased its consistency and was recommended for bread production. The data allowed us to obtain response surface models and the optimal substitution percentages to produce bread using GQF-GKF, GQF-GCF, and GKF-GCF blends. [ABSTRACT FROM AUTHOR]

The production of raw-crushed wind-turbine blade (RCWTB) and its addition to conventionally designed self-compacting Concrete (SCC) enable us to provide a second life to wind-turbine blades. However, SCC containing RCWTB must show proper fresh behavior, an aspect evaluated in this paper both experimentally and through simulations based on computational fluid dynamics (CFD) for RCWTB additions up to 3.0% by volume. In experimental terms, RCWTB reduced the flowability and passing ability of SCC, and slowed SCC flow, although the performance of SCC with 1.5% RCWTB was adequate under free-flow conditions. In terms of modeling, RCWTB did not impact yield stress and increased plastic viscosity. CFD modeling under free flow, regardless of the presence or not of obstacles simulating concrete reinforcement, was successful, especially in the long term. Nevertheless, the modeling of the passing ability was not accurate; precision could be improved by simulating the effect of the individual GFRP fibers within the SCC flow. Finally, the mechanical properties of SCC were negatively impacted by RCWTB, the stitching effect of the GFRP fibers not being effective in an SCC with a conventional design. A specific SCC design when adding RCWTB is therefore needed to advance in the use of this waste in this concrete type. [ABSTRACT FROM AUTHOR]

Guar (Cyamopsis tetragonoloba L.), a summer legume, is becoming increasingly important as an industrial crop due to its high gum and viscosity content. This study investigated the effects of methyl jasmonate (MeJA), chitosan (CH), and their combination on the growth, yield, and quality of guar under irrigation regimes. A greenhouse experiment was conducted using a factorial design to evaluate the effect of foliar spraying with MeJA (5, 25, and 50 µM), CH (100, 150, and 200 mg/L), their combination (25 µM MeJA + 150 mg/L CH), and control on two commercial guar varieties (RGC-986 and BR-2017) under different irrigation regimes (100%, 70%, and 40% field capacity). The results showed that the exogenous application of MeJA and CH, individually and in combination, significantly enhanced various morphological traits and yield components in guar, including plant height, pod characteristics, seed yield, and root development. Additionally, the combination treatments improved seed quality parameters, such as gum percentage and viscosity content. Leaf analysis revealed increased levels of total phenolic content, total flavonoid, and anthocyanin contents. The BR-2017 variety showed superior performance in most morphological and qualitative traits, demonstrating greater resistance to irrigation regimes. It maintained yield and quality characteristics under water-deficit conditions, particularly when treated with 25 µM MeJA and 150 mg/L CH. The highest gum percentage (33.67%) and viscosity (4768.5 cP) were observed in the RGC-986 variety, along with enhanced levels of secondary metabolites. This study provides new insights into how MeJA, CH, and their combination can improve the yield and quality of guar under water deficit stress conditions. The results suggest that the use of these elicitors, especially in combination, represents an innovative strategy for improving guar production and quality, with potential variety-specific responses to water-deficit stress. [ABSTRACT FROM AUTHOR]

This paper presents the establishment of a sensory evaluation system for purple sweet potato rice steamed sponge cake (PSPRSSC) utilizing fuzzy mathematics. Initially, eight key sensory evaluation indices were identified through expert consultations. These indices were subsequently prioritized using fuzzy binary comparison, resulting in the following order: aroma, taste, crust color, elasticity, viscosity, chewiness, hardness, and brightness. The corresponding weight values assigned to each index were 23%, 18%, 16%, 13%, 12%, 8%, 6%, and 4%, respectively. Notably, aroma was found to have a more significant impact than visual attributes in the sensory evaluation of PSPRSSC. Based on this prioritization, comprehensive sensory evaluation criteria for PSPRSSC were formulated. Verification tests confirmed the efficacy of the proposed evaluation system. This study provides critical data and theoretical support for the sensory quality assessment of PSPRSSC, thereby facilitating its industrialization and enhancing its market viability. [ABSTRACT FROM AUTHOR]

The shear flow and solid–liquid transition of mixed milk protein dispersions with varying concentrations of casein micelles (CMs) and serum proteins (SPs) are integral to key dairy processing operations, including microfiltration, ultrafiltration, diafiltration, and concentration–evaporation. However, the rheological behavior of these dispersions has not been sufficiently studied. In the present work, dispersions of CMs and SPs with total protein weight fractions (ωPR) of 0.021–0.28 and SP to total protein weight ratios (RSP) of 0.066–0.214 and 1 were prepared by dispersing the respective protein isolates in the permeate from skim milk ultrafiltration and then further concentrated via osmotic compression. The partition of SPs between the CMs and the dispersion medium was assessed by measuring the dry matter content and viscosity of the dispersion medium after separating it from the CMs via ultracentrifugation. The rheological properties were studied at 20 °C via shear rheometry, and the sol–gel transition was characterized via oscillatory measurements. No absorption of SPs by CMs was observed in dispersions with ωPR = 0.083–0.126, regardless of the RSP. For dispersions of SPs with ωPR ≤ 0.21, as well as the dispersion medium of mixed dispersions with ωPR = 0.083–0.126, the high shear- rate-limiting viscosity was described using Lee's equation with an SP voluminosity (vSP) of 2.09 mL·g−1. For the mixed dispersions with a CM volume fraction of φCM ≤ 0.37, the relative high shear-rate-limiting viscosity was described using Lee's equation with a CM voluminosity (vCM) of 4.15 mL·g−1 and a vSP of 2.09 mL·g−1, regardless of the RSP. For the mixed dispersions with φCM > 0.55, the relative viscosity increased significantly with an increasing RSP (this was explained by an increase in repulsion between CMs). However, the sol–gel transition was independent of the RSP and was observed at φCM ≈ 0.65. [ABSTRACT FROM AUTHOR]

This research explores the extraction of ferulated arabinoxylans (FAXs) from maize bran and their incorporation into wheat flour to assess their impact on rheological and pasting properties. Flour blends were prepared with FAX concentrations of 0%, 2%, 4%, 6%, 8%, and 10%, and these blends were then evaluated using farinograph, mixograph, micro-extensibility, and viscosity analyses. The results indicated that farinograph water absorption increased significantly (p ≤ 0.05), ranging from 54.9% to 60.5%, as the FAX content rose, correlating with higher gel-forming potential. Notably, the 2% FAX treatment (FAX2) exhibited the longest dough development time at 24.7 min. Stability and mixing time index (MTI) values also varied significantly (p ≤ 0.05) among treatments, with FAX2 displaying a longer mixing time of 14.4 ± 3.3 min. A pasting analysis revealed a significant decrease in peak and hot paste viscosity (p < 0.05) with increasing FAX concentrations, suggesting an association between lower hot paste viscosity and reduced breakdown. Micro-extensibility measures further indicated that blends with 0% and 2% FAX had greater extensibility, while the 4% FAX blend showed higher resistance. Overall, this research aims to advance the understanding of how these components can enhance flour functionality and contribute to the development of healthier, higher-quality baked products. [ABSTRACT FROM AUTHOR]

This work presents a numerical study incorporating the impact of temperature variations along the fracture on the viscosity of fracturing fluids and consequently on proppant distribution in hydraulic fracturing. Traditional models have not considered non-uniform temperature distributions, resulting in less accurate predictions of proppant migration and distribution. The proposed model integrates the thermal variations to enhance the understanding of proppant dynamics under realistic field conditions. The proposed model is validated through physical experiments, demonstrating significant differences in proppant placement due to temperature- induced viscosity changes. Our results show that proppant distribution is substantially affected by lower temperatures at the fracture opening and higher temperatures at the distal end, contrasting sharply with distribution patterns observed under uniform viscosity conditions. As the temperature at the fracture opening decreases, the viscosity of the fracturing fluid increases, enhancing its capacity to transport proppant. The increased viscosity facilitates the transport of proppant deeper into the fracture, resulting in a reduction of the total amount of proppant near the fracture opening and a smaller stacking angle compared to those observed at fixed viscosities of 10, 100, and 200 mPa sThe findings offer critical insights into the mechanics of proppant flow, holding substantial theoretical and practical implications for optimizing hydraulic fracturing treatments. [ABSTRACT FROM AUTHOR]

The gas production of deep coalbed methane wells in Linxing-Shenfu block decreases rapidly, the water output is high, the supporting effect is poor, the effective supporting fracture size is limited, and the migration mechanism of proppant in deep coal reservoir is not clear at present. To investigate the migration behavior of proppants in complex fractures during the volume reconstruction of deep coal and rock reservoirs, an optimization test on the conductivity of low-density proppants and simulations of proppant migration in complex fractures of deep coal reservoirs were conducted. The study systematically analyzed the impact of various fracture geometries, proppant types and fracturing fluid viscosities on proppant distribution. Furthermore, the study compared the outcomes of dynamic proppant transport experiments with simulation results. The results show that the numerical simulation is consistent with the results of the proppant dynamic sand-carrying experiment. Under the conditions of low viscosity and large pumping-rate, a high ratio of 40/70 mesh proppant can facilitate the movement of the proppant to the depths of fractures at all levels. The technical goal is to create comprehensive fracture support within intricate trapezoidal fractures in deep coal and rock reservoirs without inducing sand plugging. The sand ratio is controlled at 15%–20%, with a proppant combination ratio of 40/70:30/50:20/40 = 6:3:1. Proppant pumping operations can effectively address the issue of poor support in complex fractures in deep coal formations. The research results have been successfully applied to the development of deep coalbed methane in the Linxing-Shenfu block, Ordos Basin. [ABSTRACT FROM AUTHOR]

External vibrations are known to be one of the promising ways to control the behavior of multiphase systems. The computational modeling of the behavior of a gas bubble in a viscous liquid in a horizontal cylinder of square cross-section, which undergoes linearly polarized translational oscillations in weightless conditions, has been carried out. Under vibrations, the bubble moves towards the wall of the vessel with acceleration determined by the amplitudes and frequency of vibrations. Near the wall, at a distance of the order of the thickness of the viscous Stokes boundary layer, the effects of viscosity become more important and, as a result, the bubble is repelled from the wall. After some oscillations, equilibrium conditions are attained where the attractive force balances the repulsive force; accordingly, the average position of the bubble ceases to change. The numerical modelling shows that the average behaviors of a deformable bubble near a wall under normal and tangential vibration are similar. [ABSTRACT FROM AUTHOR]

Waste wood, crop residues, livestock manure and waste oil, were widely used to produce bio-oil. And then partially or completely replace the petroleum-based asphalt. But the road performance of this asphalt was insufficient. In this study, the development of green and sustainable bio-asphalt to partially replace petroleum-based asphalt with wood-based phenolic resin made by straw liquefaction products was proposed. Firstly, the separation of straw components was carried out to extract cellulose and lignin. Straw and its primary components were liquefied to explore the main factors influencing the liquefaction of straw. Then the liquefied products were combined with formaldehyde to synthesize lignin-based phenolic resin WPR. And the phenolic resin PR, which was obtained from the reaction with phenol, was compared and analyzed. Finally, the resin was put into matrix asphalt with different ratios to prepare bio-asphalt, and the performance of the bio-asphalt was analyzed by the three major indexes of each bio-asphalt and viscosity. The results showed that the liquefaction rate of straw mainly depended on the liquefaction rate of cellulose, and its liquefaction reaction was complex, with a reaction kinetic level of 1. 71. From the resin yield and liquefaction products, WPR, PR FT-IR spectral analysis showed that the WPR resin synthesis rate was higher and had a better reactivity than the PR. Only when mixed with the liquefaction products, the performance of the bio-asphalt prepared was poorer. However, when mixed with WPR resin, the bio-asphalt's high temperature stability, low-temperature cracking resistance, deformation resistance, and temperature stability were better than matrix asphalt [ABSTRACT FROM AUTHOR]

The performance of a stirred bioreactor was evaluated in this study in terms of the bubble hydrodynamics and the mass transfer efficiency, using a non‐viscous Newtonian fluid of water, a viscous non‐Newtonian fluid of xanthan, and a viscous non‐Newtonian fluids of xanthan with dispersed soybean powder, respectively. The computational fluid dynamics–population balance model (CFD‐PBM) method coupled with the viscosity model and the mass transfer model is established to simulate the gas–liquid mass transfer process and bubble size distribution in the stirred bioreactor. The results demonstrate that the rheological properties of the fluid play an important role in determining the gas holdup, the mass transfer efficiency, and the bubble size distribution. Viscosity of the fluid exhibits a negative impact on gas–liquid mass transfer rate and gas holdup. Moreover, by properly adjusting the operating conditions such as the stirrer speed, it is possible to modulate the gas dispersion and mass transfer rate in the reactor. [ABSTRACT FROM AUTHOR]

The fluid's viscosity significantly affects the performance of a centrifugal pump. The entropy production method and leakage are employed to analyze the performance changes under various viscosities by numerical simulation and validated by experiments. The results showed that increasing viscosity reduces both the pump head and efficiency. In addition, the optimal operating point shifts to the left. Leakage is influenced by vortex distribution in the front chamber and boundary layer thickness in wear-ring clearance, leading to an initial increase and subsequent decrease in leakage with increasing viscosity. The total entropy production S pro , Total inside the pump rises with increasing viscosity. The different mechanisms dominate under varying conditions: Turbulent dissipation dominates at low viscosity. Under high-viscosity conditions, energy loss is primarily caused by direct dissipation S pro , D and wall entropy production S pro , W . This study provides a deeper and more objective understanding of the energy characteristics of centrifugal pumps handling fluids of various viscosity, potentially aiding in optimizing pump design and improving energy conversion efficiency. [ABSTRACT FROM AUTHOR]

Aqueous solutions of nonionic surfactants behave differently than those of ionic surfactants. Micellar properties and structural characterization of Polysorbate 80 (commonly known as Tween 80) were investigated in the presence of different additives at different temperatures (303–323 K) by using cloud point (CP), densitometry, and viscometry techniques. Nonionic surfactant shows the optimum effect when used near their CP, as the presence of additives strongly influences them. The compounds or additives that break the structure of water will increase the CP, while those that help to build the water structure show a decrease in the CP. Adding ester, urea, and carbohydrates decreases the CP of Polysorbate 80, while alcohol and thiourea show the opposite trend. Density and viscosity measurements of Polysorbate 80 in the presence of monovalent salts (NaX, X = Cl–, Br–, , and salicylate) confirmed the change in molecular structure. [ABSTRACT FROM AUTHOR]

In this work, the shear viscosity (η) of the liquid alkali metals including Rb, Cs, and Na is determined based on the Stokes–Einstein's equation by an improved mean spherical approximation theory using an effective square-well potential relation for intermolecular interaction in a wide range of densities and temperatures. In this way, the PVT data and the linear isothermal regularity equation of state are used to determine the radial distribution function at a contact point at any thermodynamic state. The results obtained showed that the calculated values for viscosity increased strongly with increasing density and increased slightly with temperature. A reasonable agreement has been found between the calculated values of η and their available experimental data. Furthermore, a correlation relation between the effective molecular diameter and the temperature was found and the order of magnitude and sign of the coefficients were determined. [ABSTRACT FROM AUTHOR]

Saponite is classified as a trioctahedral mineral of the smectite group.Natural saponite of the Lomonosov deposit (Arkhangelsk region, Russia) is represented as Na- or Ca- forms according to XRD analysis. The interlayer space of the structure contains water molecules. The saponite clay sampled at the deposit is represented by pulp. The clay powder for the research was obtained by the technology of concentrating fine clay material. The crystallochemical formula of saponite was calculated based on the data obtained from XRD, XRF and atomic emission analyses. The purpose of the research was to study the effect of mixed sodium carbonate-sulfate electrolyte (Na2SO4 - 80%; Na2CO3-20%), polyacrylamide (PAA) and low viscosity polyanionic cellulose (PAC L) on the structure, filtration and rheological properties of saponite suspension. The optimum solids content in the water suspension of saponite clay was determined to be in the range of 85-100 g/l. Going out of range leads to deterioration of filtration properties presented by significant increase in filtration loss or increased thickness of the filtration cake. Filtration loss at 85 g/l solids content in the water suspension was 22 cm³/30 min. Addition of mixed sodium carbonate-sulfate electrolyte to the saponite suspension improved rheological properties, but increased filtration loss to 34-36 cm³/30 min. The admixture of polyacrylamide leads rather quickly to flocculation and sedimentation of clay particles; filtration loss was 16-21 cm³/30 min. The presence of polyanionic cellulose in the suspension creates a gel structure, increasing the viscosity of the mud system and significantly reducing filtration loss to 7-9 cm³/30 min. [ABSTRACT FROM AUTHOR]

We report measurements performed to understand the effects of gas (QG) and liquid (QL) flow rates, surface tension (σGL), liquid viscosity (μL), and particle diameter (dp) on dynamics of local liquid spreading, pressure drop, and overall liquid holdup in a pseudo‐2D trickle bed. We show that an increase in the gas‐phase inertia leads to a decrease in the lateral liquid spreading, whereas an increase in the liquid‐phase inertia leads to an increase in the lateral liquid spreading. We also show that an increase in dp causes a reduction in the lateral liquid spreading. Using dimensionless numbers (AB and We), we propose a regime map showing contributions of different forces to the local liquid spreading. We show that the interplay between the inertia and capillary forces governs the liquid distribution near the inlet, whereas the relative contribution of gravitational force increases toward the outlet. Finally, we propose a relation between AB and We for "bed‐scale" liquid spreading. [ABSTRACT FROM AUTHOR]

ABSTRACT A time‐dependent nonlinear model that describes the generation of vortex patterns of dust grains in a magnetized strongly coupled dusty plasma where ions are taken magnetized [Nebbat and Annou, Phys. Plasmas 30 (8), 082108 (2023)] is augmented. The effect of viscosity and dust charge variation on the characteristics of the vortex is investigated. [ABSTRACT FROM AUTHOR]

Highlights Nowadays, inorganic fillers are widely used to enhance pressure‐sensitive adhesives (PSAs), but inorganic fillers have problems with poor compatibility and agglomeration. Furthermore, these types of PSAs usually have an antagonistic effect: as the shear performance improves, the initial tack decreases. This severely limits the application of PSAs. Herein, white carbon black (WCB) grafted with polyisoprene (PI) was prepared and used to enhance polyisobutylene‐based PSAs, and the optimal reaction conditions of grafting were explored. The shear and peel strength of PSAs all increase with the increase of the mass fraction of fillers. When the filler content is less than 10 wt%, the initial tack of PSAs increases. When the filler content exceeds 10 wt%, the initial viscosity of PSAs decreases, but it is still far higher than that of the unmodified WCB‐reinforced PSAs system. In addition, the rheological performances of PSAs were tested, further exploring the role of particle grafting in PSAs. PSAs reinforced with white carbon black grafted with polyisoprene were prepared. The optimal conditions for modified white carbon black have been determined. The grafting fillers have improved all the performance of PSAs. The grafting of fillers significantly reduces the antagonistic effect of PSAs. Rheology was used to explore the effect of filler grafting in the PSAs. [ABSTRACT FROM AUTHOR]

Background Purpose Methods Results Conclusions The relaxivity of magnetic resonance imaging (MRI) contrast agents is primarily attributed to metal ions such as gadolinium (Gd) and iron. However, the impact of organic solutes on relaxivity, particularly through alterations in water molecule dynamics, has not been thoroughly investigated. This research was aimed to explore how organic solutes affect the relaxivities of water and Gd‐based contrast agents (GBCAs), potentially revealing new aspects for the development of contrast agents.To investigate the effects of different proportions of water‐soluble organic solvents mixed with pure water and GBCA on T1 and T2 relaxivities.Ethanol, dimethyl sulfoxide (DMSO), 1,4‐dioxane, glycerin, ethylene glycol, diethylene glycol, polyethylene glycol (PEG) 200, and PEG 400 were mixed with ultrapure water in various ratios (100:0, 90:10, 80:20, 70:30, 60:40, 50:50, 40:60, 30:70, 20:80, 10:90, 0:100). GBCA was added to these mixtures at a concentration of 0.05 mmol/L. The mixtures underwent T1 and T2 mapping scans using a 3.0 Tesla MRI machine, and the relaxivities R1 (1/T1) and R2 (1/T2) were calculated and compared.The relaxivity R1 of ethanol, 1,4‐dioxane, and DMSO mixtures with water or GBCA, as well as R2 of DMSO mixtures with GBCA, initially increased and then decreased. Conversely, R1 and R2 increased significantly with higher proportions of diethylene glycol, PEG 200, and glycerin in the mixtures with GBCA. The increase in relaxivity R1 was correlated with greater viscosity. When the proportion of DMSO and diethylene glycol exceeded 20%, minimal variability in R2 was observed as the water content decreased.Adding organic solvents to water and paramagnetic relaxation reagents could alter T1 and T2 relaxivities, suggesting potential new directions for modifying current contrast agents. Additionally, increasing the viscosity of the contrast agent was found to enhance the relaxivity. [ABSTRACT FROM AUTHOR]

In the study, in order to develop novel starter cultures, three types of yoghurt were produced with different combinations of autochthonous yoghurt bacteria and the samples were investigated in terms of fermentation, microbiological quality, physicochemical properties (pH, acidity, water-holding capacity, apparent viscosities, and rheological properties), organic and benzoic acid contents, and sensory properties during 28 days. Lactobacillus delbrueckii subsp. bulgaricus content of all samples was between 7.29 and 8.58, and Streptococcus thermophilus content was between 8.03 and 9.02 log CFU/g during storage. Yoghurt type and storage time statistically affected pH, acidity, water-holding capacity, apparent viscosity, rheological properties, organic and benzoic acid content, and some sensory parameters. The general acceptability scores of the probiotic, traditional, exopolysaccharide, and control samples during storage were 8.27, 7.82, 7.53, and 7.47 respectively. Moreover, the results revealed that the strain combinations for probiotic, traditional, and exopolysaccharide yoghurt samples can be used as novel starter cultures for yoghurt production. [ABSTRACT FROM AUTHOR]

To screen julolidine derivatives containing a pyrazole group with excellent fluorescence properties and promising applications in multistimuli‐responsive fluorescent materials, three novel compounds were designed and synthesized by connecting pyrazoles through typical conjugated bonds: imine (T1), dihydrazone (T2), and acylhydrazone (T3). The molecular structure of the title compounds was characterized by 1H NMR, 13C NMR, and HR‐MS. The representative compound T3 was verified by single crystal X‐ray diffraction. Although the three compounds have roughly similar conjugated structures, dissimilarity in their fluorescence properties was apparent. The results of fluorescence studies showed that the compound T3, which was connected to julolidine and pyrazole by an acylhydrazone bond, exhibited excellent fluorescence performance compared to the other compounds T1 and T2. Compound T3 can also respond to external stimuli, such as solvent viscosity, organic acids/bases, and mechanical forces. In addition, T3 could also specifically detect Cu2+ ions, and the fluorescence titration data indicated that the low limit of detection (LOD) of compound T3 for Cu2+ is 0.26 µM within the range from 0 to 50 µM. Therefore, this work provides a preliminary basis for the development of multistimuli‐responsive fluorescent molecular materials containing acylhydrazone fragment. [ABSTRACT FROM AUTHOR]

We review some recent developments in mathematical aspects of relativistic fluids. The goal is to provide a quick entry point to some research topics of current interest that is accessible to graduate students and researchers from adjacent fields, as well as to researches working on broader aspects of relativistic fluid dynamics interested in its mathematical formalism. Instead of complete proofs, which can be found in the published literature, here we focus on the proofs' main ideas and key concepts. After an introduction to the relativistic Euler equations, we cover the following topics: a new wave-transport formulation of the relativistic Euler equations tailored to applications; the problem of shock formation for relativistic Euler; rough (i.e., low-regularity) solutions to the relativistic Euler equations; the relativistic Euler equations with a physical vacuum boundary; relativistic fluids with viscosity. We finish with a discussion of open problems and future directions of research. [ABSTRACT FROM AUTHOR]