The Rehydration Ability of Whey Ingredients

The purpose of this research was to studythe ability of whey protein concentrates (WPC) and whey permeate produced with ultrafiltration of cheese whey to rehydrate. The products studied were cheese whey concentrate witha PDM percentage of 80% (WPC-80), and cheese whey permeate, both produced under the conditions of the PJSC Dairy “Voronezhsky”.WPC-80 and the whey permeate dissolution processes were studied using microscopy. Water-impermeable hydrophobic layers were formed at the boundary, preventing water penetration into dry particles. The result was a higher dissolution timeforWPC-80 compared with whey permeate. When WPC-80 came into contact with water,it initially formed an obtuse wetting angle with a slow change over time. Whey permeate reached the equilibrium wetting angle more quickly. Quickreconditioning of WPC moisture content required avoiding capillary penetration of water, which created a turbulent liquid flow. The application of these ingredients in different food industry areas can reduce the costs for finished products, contribute to cost-effectiveness, increase the total production, and reduce environmental risks. Keywords: whey protein concentrate, whey permeate powder, water-wetting, dissolution

Study of the Effect of Wetting on Viscous Fingering Before and After Breakthrough by Lattice Boltzmann Simulations

We present a suite of numerical simulations of two-phase flow through a 2D model of a porous medium using the Rothman-Keller Lattice Boltzmann Method to study the effect of viscous fingering on the recovery factor as a function of viscosity ratio and wetting angle. This suite involves simulations spanning wetting angles from non-wetting to perfectly wetting and viscosity ratios spanning from 0.01 through 100. Each simulation is initialized with a porous model that is fully saturated with a "blue" fluid, and a "red" fluid is then injected from the left. The simulation parameters are set such that the capillary number is 10, well above the threshold for viscous fingering, and with a Reynolds number of 0.2 which is well below the transition to turbulence and small enough such that inertial effects are negligible. Each simulation involves the "red" fluid being injected from the left at a constant rate such in accord with the specified capillary number and Reynolds number until the red fluid breaks through the right side of the model. As expected, the dominant effect is the viscosity ratio, with narrow tendrils (viscous fingering) occurring for small viscosity ratios with M ≪ 1, and an almost linear front occurring for viscosity ratios above unity. The wetting angle is found to have a more subtle and complicated role. For low wetting angles (highly wetting injected fluids), the finger morphology is more rounded whereas for high wetting angles, the fingers become narrow. The effect of wettability on saturation (recovery factor) is more complex than the expected increase in recovery factor as the wetting angle is decreased, with specific wetting angles at certain viscosity ratios that optimize yield. This complex phase space landscape with hills, valleys and ridges suggests the dynamics of flow has a complex relationship with the geometry of the medium and hydrodynamical parameters, and hence recovery factors. This kind of behavior potentially has immense significance to Enhanced Oil Recovery (EOR). For the case of low viscosity ratio, the flow after breakthrough is localized mainly through narrow fingers but these evolve and broaden and the saturation continues to increase albeit at a reduced rate. For this reason, the recovery factor continues to increase after breakthrough and approaches over 90% after 10 times the breakthrough time.

Design and Development of a Novel Ultrasonic Field Wetting Angle Measuring Instrument for Researching the Wetting of the Liquid–Solid Interface

A key technical problem in the preparation of Al-Ti-C grain refiner and other composite materials is the poor wetting of the Al-C interface, which greatly restricts the development of the preparation technology of related composite materials. In view of this scientific challenge, a novel ultrasonic field wetting angle measuring instrument has been designed to research the wetting behavior of the liquid–solid interface and ensure that preparation conditions are optimized. The dimensional parameters of the ultrasonic transducer and the horn in the novel ultrasonic wetting angle measuring instrument have been designed by theoretical calculation, and the modal analysis was performed for the ultrasonic horn using the functions of displacement and time. Modal analysis was utilized to optimize the dimension of the ultrasonic horn, and the natural frequency of the longitudinal vibration of the horn was reduced from 22,130 Hz to 22,013 Hz, resulting in an error rate between the actual value (22,013 Hz) and the design value (20 kHz) of less than 1%. In addition, the influence of different transition arc radiuses on the maximum stress of the optimized ultrasonic horn was analyzed.

The Influence of Organically Modified Derivatives of Silica on the Structure and the Wetting Angle Values of Silica Coatings

The surrounding environment often acts in a destructive way on materials we apply in our everyday life. The best way to protect them against such activity is to cover the basic materials with coatings possessing different properties, tailored to their applications. Anticorrosive layers are one of the biggest groups of such protective coatings, especially those containing silica or its derivatives. Depending on a type of silica precursor and a method of deposition, one can obtain coatings of different structures and properties. In this work, three different silica precursors were applied: TEOS (tetraethylorthosilane), DDS (dimethyldiethoxysilane) and AerosilTM (the powder silica). Sols of different concentrations of the aforementioned precursors as well as commercially available preparations (Sarsil H1 4/2 and SILOXAN W290) were applied for thin films deposition by a dip coating or an infiltration method. The substrates could be divided in two groups: metallic (steel and titanium or titanium alloys) and porous (represented by old brick, sandstone and limestone). Following the deposition process, the layers on metallic substrates were additionally annealed at 500 °C to improve their adhesion and mechanical properties, while those on porous materials were dried in air. All prepared coatings were primarily studied by FTIR spectroscopy and X-ray diffraction. The morphology of their surfaces was imaged by SEM and AFM microscopies, which also allowed determination of the roughness of obtained materials. The measurements of wetting angle values enabled to find the relationship between the surface topography, the type of silica precursor and the hydrophobic/hydrophilic properties of the samples. The results confirmed the hydrophobic properties of coatings obtained by the infiltration technique on the porous materials and the high hydrophilicity of the annealed thin film deposited on the metallic substrates.

Optimization of titanium dioxide wetting in alkyd paint and varnish materials in the presence of surfactants

This paper reports the results of studying the influence of surfactants (SAS) on the wetting of titanium dioxide in alkyd paint and varnish materials (PVM), based on pentaphthalic (PPh) and alkyd-urethane (AU) film-forming substances. Edge wetting angle (θ°) and adhesion work (Wa) were used as the criteria for assessing the wettability of titanium dioxide. Three additives were used as SAS: the original product AS-1, obtained from waste of oil refining (with low cost), and industrial additives: "Telaz" and polyethylene polyamine (PEPA). All the studied additives in PPh and AU PVM improve the wetting of titanium dioxide. At the 30 % content of AS film-forming substance in the composition, the maximum decrease in θ° for AS-1 is 4.5°, for PEPA and Telaz it is 4°. For pentaphthalic composition under similar conditions, a decrease in edge wetting angle for AS-1 is 10 °, for Telaz 8.6°, and for PEPA 5.9°. According to the relative change in edge wetting angle for both systems, the maximum decrease in θ° is about 10 %. The introduction of SAS into the composition of AU ambiguously affects the adhesion work, for PPh, the introduction of SAS causes a decrease in adhesion work (Wa). AS-1 is the SAS that minimally reduces adhesion work. The compositions of the PVM by the method of probabilistic-deterministic planning, which ensures maximum wetting of titanium dioxide with film-forming solutions, were analyzed. The equations for calculating the edge angle of wetting of titanium dioxide depending on the content of solvent and the SAS in the PVM were derived. The effectiveness of the AS-1 product as a wetting additive for alkyd paints and varnishes was proven. The wetting ability of the original SAS – AS-1 is close to industrial additives PEPA and Telaz.

Effects of Particle Combinations With Different Wettability on Foam Structure and Stability

Particle addition is an important method to prepare foam metal, and it is of great significance to clarify the mechanism of particle stabilizing liquid metal foam. In this paper, ethanol-water solution system is used to simulate liquid melt foam. By changing the wettability of particles to adjust the distribution position of particles in foam, two types of particles with different wettability are added, which are mixed and optimized in a certain proportion to improve the foam stability as much as possible. The main mechanism is that the large wetting angle particles at the gas-liquid interface to slow down the gas migration, while small wetting angle particles exist in the liquid film, which can reduce the liquid drainage velocity. The experimental results show that the effect of particle wettability on foam structure is greater than that on viscosity enhancement. The particles with large wetting angle are beneficial to the formation and stability of foam, and the particles with small wetting angle cannot stabilize the foam alone. The effect of two types of particle combinations with different wettability on foam stability is better than that of single type of particle. Considering the height and uniformity of the foam structure, the optimal particle combination is finally obtained.

Influence of Wetting on Viscous Fingering Via 2D Lattice Boltzmann Simulations

We present simulations of two-phase flow using the Rothman and Keller colour gradient Lattice Boltzmann method to study viscous fingering when a “red fluid” invades a porous model initially filled with a “blue” fluid with different viscosity. We conducted eleven suites of 81 numerical experiments totalling 891 simulations, where each suite had a different random realization of the porous model and spanned viscosity ratios in the range $$M\in [0.01,100]$$ M ∈ [ 0.01 , 100 ] and wetting angles in the range $$\theta _w\in [180^\circ ,0^\circ ]$$ θ w ∈ [ 180 ∘ , 0 ∘ ] to allow us to study the effect of these parameters on the fluid-displacement morphology and saturation at breakthrough (sweep). Although sweep often increased with wettability, this was not always so and the sweep phase space landscape, defined as the difference in saturation at a given wetting angle relative to saturation for the non-wetting case, had hills, ridges and valleys. At low viscosity ratios, flow at breakthrough is localized through narrow fingers that span the model. After breakthrough, the flow field continues to evolve and the saturation continues to increase albeit at a reduced rate, and eventually exceeds 90% for both non-wetting and wetting cases. The existence of a complicated sweep phase space at breakthrough, and continued post-breakthrough evolution suggests the hydrodynamics and sweep is a complicated function of wetting angle, viscosity ratio and time, which has major potential implications to Enhanced Oil Recovery by water flooding, and hence, on estimates of global oil reserves. Validation of these results via experiments is required to ensure they translate to field studies.

Static wetting angles of water and sulphur at the zinc sulphide surface modified with anionic surfactants and their combinations

This paper looks at the effect produced by surface modification of the super pure zinc sulphide monocrystals with certain surfactants and their combinations (sodium lignosulphonate (SLS), sodium dodecyl sulphate (SDS), sodium dodecylbenzenesulphonate (SDBS) and the following combinations: SLS + SDS, SLS + SDBS on the surface angle of wetting with water and elemental sulphur melt. It was found that as the concentration of individual surfactants in the solution rose, so did the wetting ability of the mineral surface. Thus, at the surfactant concentration of 0.8 g/dm3 the water wetting angle reaches 48.4o for SLS, 22.5o for SDS and 10.3o for SDBS; the elemental sulphur wetting angle is 71.3o for SLS, 76.9o for SDS and 67.9o for SDBS. The work of adhesion in the system ZnS – Surfactant – Н2О increases by 9–11%, and in the system ZnS – Surfactant – S0 — by 5–8%. When using the combinations SLS + SDS (СSLS = 0.2–0.8 g/dm3) and SLS + SDBS (СSLS = 0.2 g/dm3), inverse surface wetting of zinc sulphide with elemental sulphur melt is observed. The maximum wetting angles reached are 93o and 85o, correspondingly. The work of adhesion and the spreading coefficient expectedly decrease. The paper analyzes the effect of individual surfactants and their combinations on the pressure leaching of zinc sulphide concentrate. The use of individual surfactants intensifies the transition of valuable components into the solution. The biggest increase in recovery was seen when using SLS, and namely 27–32% for zinc and 11–16% for copper. The recovery of zinc increased by 31–41% in the presence of SLS + SDS and by 27–34% in the presence of SLS + SDBS. This research was funded by the Russian Science Foundation, Grant No. 18-19-00186.

Determination of the wetting angle using gas bubble method

Most of the technological processes of coal mining and primary processing (transportation, crushing, and enrichment) depend on the physical and chemical properties of the external surface of coal particles. When determining the wetting angle — the wettability characteristics of the coal surface — the method of preparing the working surface of the sample and the choice of the measurement procedure (a drop of liquid on a solid surface or fixing a gas bubble on the surface of coal placed in water) are of great importance. We present the results of determining the contact angle of wetting using an air bubble. The working surface was prepared by briquetting a powdered sample. Scanning electron microscopy and laser diffraction analysis of the particle size distribution were used for surface characterization and fractional analysis of carbon particles. It is shown that the contact angle of wetting depends on the particle size, mineral composition of coal, and pressing pressure. At the same time, when determining the wetting angle, the optimal particle size and pressing pressure of the briquette are <100 μm and ~500 MPa, respectively. The obtained results can be used to improve technologies for mining, conversion and dressing of coals.

Adsorption of bacteriophages on polypropylene labware affects the reproducibility of phage research

Hydrophobicity is one of the most critical factors governing the adsorption of molecules and objects, such as virions, on surfaces. Even moderate change of wetting angle of plastic surfaces causes a drastic decrease ranging from 2 to 5 logs of the viruses (e.g., T4 phage) in the suspension due to adsorption on polymer vials' walls. The effect varies immensely in seemingly identical containers but purchased from different vendors. Comparison of glass, polyethylene, polypropylene, and polystyrene containers revealed a threshold in the wetting angle of around 95°: virions adsorb on the surface of more hydrophobic containers, while in more hydrophilic vials, phage suspensions are stable. The polypropylene surface of the Eppendorf-type and Falcon-type can accommodate from around 108 PFU/ml to around 1010 PFU/ml from the suspension. The adsorption onto the container’s wall might result in complete scavenging of virions from the bulk. We developed two methods to overcome this issue. The addition of surfactant Tween20 and/or plasma treatment provides a remedy by modulating surface wettability and inhibiting virions' adsorption. Plastic containers are essential consumables in the daily use of many bio-laboratories. Thus, this is important not only for phage-related research (e.g., the use of phage therapies as an alternative for antibiotics) but also for data comparison and reproducibility in the field of biochemistry and virology.