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The complexation of microgels with rigid nanoparticles is an effective way to impart novel properties and functions to the resulting hybrid particles for applications such as in optics, catalysis, or for the stabilization of foams/emulsions. The nanoparticles affect the conformation of the polymer network, both in bulk aqueous environments and when the microgels are adsorbed at a fluid interface, in a non-trivial manner by modulating the microgel size, stiffness and apparent contact angle. Here, we provide a detailed investigation, using light scattering, in-situ atomic force microscopy and nano-indentation experiments, of the interaction between poly(N-isopropylacrylamide) microgels and hydrophobized silica nanoparticles after mixing in aqueous suspension to shed light on the network reorganization upon nanoparticle incorporation. The addition of nanoparticles decreases the microgels' bulk swelling and thermal response. When adsorbed at an oil-water interface, a higher ratio of nanoparticles influences the microgel's stiffness as well as their hydrophobic/hydrophilic character by increasing their effective contact angle, consequently modulating the monolayer response upon interfacial compression. Overall, these results provide fundamental understanding on the complex conformation of hybrid microgels in different environments and give inspiration to design new materials where the combination of a soft polymer network and nanoparticles might result in additional functionalities. [ABSTRACT FROM AUTHOR]

A comprehensive research has been carried out to develop a method for obtaining particle size standards based on aqueous suspensions of polystyrene latex spheres. For the synthesis of suspensions, a method of seeded emulsion polymerization of styrene under excess amount of dispersion medium is proposed. The equipment from the State Primary Standard of Units of Dispersed Parameters of Aerosols, Suspensions and Powder Materials (GET 163-2020) was used in the work. The particle size distribution of the suspension samples synthesized during the study was analyzed by the methods of dynamic light scattering and laser diffraction. The metrological characteristics of synthesized suspensions have been studied. It was established that depending on the methods of emulsion polymerization and micro-emulsification of styrene, monodisperse microspheres of polystyrene latex of various diameters can be obtained. The effect of the amount of introduced surfactant on the process of quasi-spontaneous micro-emulsification of the monomer during seeded polymerization was studied. Based on the study results, aqueous suspensions of monodisperse polystyrene latex spheres with a median particle diameter of 0.31 and 0.54 μm were proposed as particle size standards. The study results can be used to obtain monodisperse particles larger than 1 μm by seeded polymerization. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ecology & Rural Environment is the property of Journal of Ecology & Rural Environment Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, the adsorption and inhibition of lipid oxidation propertises of curcumin embeded ovalbumin (OVA)/sodium carboxymethylcellulose (CMC) were investigated. The results demonstrated that the adsorption of curcumin and OVA/CMC particles at the oil-water interface might form a dual protection. The larger emulsion droplets were formed at an OVA/CMC ratio of 1:2 (pH 4.4) due to bridging flocculation. In the other two ratios (1:1, 2:1), the emulsions showed good stability after 32 days of storage. At the ratios of 1:2, 1:1, and 2:1, the oxidation rate of the oil in the emulsion stabilized by OVA/CMC and OVA/CMC-Cur particles reduced by 16.2% and 37.9%, 4.9% and 38.9%, and 8.8% and 35.8%, respectively, than the pure oil. At the ratios of 1:1 and 2:1, the emulsion stabilized by the OVA/CMC-Cur particles demonstrated excellent antioxidant resistance and storage stability, particularly at the ratio of 1:1. • Curcumin and OVA/CMC particle adsorbed on the interface to form dual protection. • At the OVA/CMC ratios of 1:1 and 2:1, the emulsion showed good storage stability. • Emulsion stabilized by dual-functional OVA/CMC-Cur had better antioxidant capacity. • The OVA/CMC structure can affect the physical and antioxidant stability of emulsion. • Inhibition effect of OVA/CMC-Cur on oil oxidation was stronger than that of OVA/CMC. [ABSTRACT FROM AUTHOR]

The micro- and nanoscale characterization and mapping of surface properties and surface behaviour is critical to both physical and biological science. Mechanical contact probes are a critical tool for investigating surface and interface science, and have seen greater development and a diversification in recent years. In particular, mechanical contact probes that have been fabricated from the bottom-up by the assembly of synthesized nano- or microscale materials can provide enhanced functionality and sensitivity over traditional microcantilevers. This work provides an overview of recent developments in the field of assembled micro- and nanoscale mechanical contact probes, with a specific focus on three probe types: colloidal particle probes with high aspect ratio and a high lateral sensitivity, one-dimensional probes comprising of nanotube and/or nanowire deflection elements, and liquid metal-based probes. For each probe type, the state-of-the-art is reviewed, and their assembly, design, functionality and capabilities are discussed. An outlook on the future direction of probe development and potential applications is also given.

Excess amounts of fluoride ions (F-) in water/wastewater bring great hazards to human health and the environment. The traditional method such as precipitation by calcium ions does not work well for low-concentration F- removal. Herein, we developed a lanthanum ion (La3+)-assisted fluorapatite precipitation approach to treat F--containing water, aiming at high removal efficiency. Through an orthogonal experimental design and single-factor experiment, the optimized reaction conditions were obtained as the molar ratio of (Ca2++La3+): PO 4 3-: F-=7.5: 4: 1, Ca2+: La3+ = 90: 10, and reaction pH of 9. Under such reaction conditions, F- in water (10 mg L−1) could be well controlled under 1 mg L−1, fulfilling relevant environmental standards. No remarkable F- removal efficiency loss was found in the presence of typical anions (e.g., halides, bicarbonate, sulfate). The developed F- removal approach also worked well in a wide F- concentration range (10–200 mg L−1) and reaction temperature range (5–45 °C). Further reaction mechanism study proved that the formation of LaF x (OH) 3- x colloids was the key step, which could accumulate F- ions in water into colloids. The subsequently added Ca2+ and PO 4 3- destroyed the stable colloids, and then promoted the formation of fluorapatite with simultaneous La3+ doping, which existed as precipitate and allowed the easy separation from the reaction solution. As a by-product, the as-produced La3+-doped fluorapatite was evaluated as an adsorbent for organic pollutant removal, which possessed a high adsorption capacity (763.4 mg g−1) for the model pollutant of Congo red. Considering the facile operation process, high F- removal efficiency, wide operation temperature window, and anti-inference for co-existing anions, the La3+-assisted fluorapatite precipitation approach possessed great potential for F--containing water/wastewater treatment. [Display omitted] • The strong affinity between La3+ and F- benefited F- removal from water. • F- concentration could be lowered <1 mg L−1 through the developed approach. • The formation of fluorapatite allowed the easy separation of precipitate. • Reaction by-product of La-FAP was used as an adsorbent for organic dye removal. [ABSTRACT FROM AUTHOR]

An advanced light scattering model for Total Internal Reflection Microscopy (TIRM) is presented. The model considers the specific TIRM geometry and deals with the scattering by an axisymmetric particle of arbitrary orientation placed in a stratified medium and the imaging of the scattered field. The scattered field is computed by truncating the scattered and internal field expansions and by using spherical and plane wave expansions for the free-space dyadic Green's function. While the first expansion is valid outside a sphere enclosing the particle, the second one is valid outside the tangent planes bounding the particle from above and below. We demonstrate that in both cases, the results are the same, and thus, that the restrictive condition according to which the interface should not intersect the particle's circumscribed sphere is not relevant. The image of the scattered field is computed by using the Debye diffraction integral and fast Fourier transform, while for a better reconstruction of the particle orientation, an image processing step consisting in a contour extraction and ellipse fitting is considered. The numerical simulations dealing with scattering by a prolate spheroid provide evidence of the remarkably sensitivity of the geometric parameters of the image ellipse to the particle orientation angles, as well as, of the integral response of the detector to the distance between the particle and the interface. • Novel TIRM model for arbitrary particle orientation in stratified media. • High sensitivity of image ellipse in TIRM to particle orientation in simulations. • Contour extraction and ellipse fitting improve particle orientation accuracy. • Comprehensive scattering model for arbitrary particle orientation in stratified media. [ABSTRACT FROM AUTHOR]

Copyright of Chemistry & Industry of Forest Products is the property of Chemistry & Industry of Forest Products Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The contact angle was used to estimate the rate of evaporation of liquid droplets on bare glass or gold (Au) sputtered glass surfaces. The rate of evaporation of water (a pure liquid) was higher than non-pure liquid composed of a 3 wt% solution of silica nanoparticles (SNP) on these two solid supports. Despite using the same initial drop volume (1 µL) throughout the experiment, the base diameter of the liquid droplet after evaporation on the different surfaces interestingly showed variations. While the liquid–solid interface displayed slip-length and contact angle variations throughout the evaporation time, the slip-length variations were more pronounced with colloidal SNP on Au-sputtered glass surfaces than pure liquid on bare glass surface. Potential application of this study was also investigated in the surface control of uniform silica microwires from colloidal SNP on Au-sputtered glass surface under low temperature conditions. The kinetics of liquid drop evaporation from glass surfaces was evaluated. Differential evaporation rates were compared between Au coated and bare glass surfaces. The contact angle was used to quantify the diameter of the water drop as a measure of evaporation rate. Potential applications in the control of silica-microwires have been discussed. [ABSTRACT FROM AUTHOR]

Homogeneity and stability of flexible perovskite solar cells (PSCs) are significant for the commercial feasibility in upscaling fabrication. Concretely, the mismatching between bottom interface and perovskite precursor ink can cause uncontrollable crystallization and undesired dangling bonds during the printing process. Herein, methylammonium acetate, serving as ink assistant (IAS) can effectively avoid the micron‐scale defects of perovskite film. The in situ optical microscope is applied to prove the IAS can inhibit the colloidal aggregation and induce more adequate crystallization growth, thus avoiding the micron‐scale defects of pinholes and intergranular cracking. Concurrently, 4‐chlorobenzenesulfonic acid is introduced into the electrode surface as a passivation layer to restore the deep traps at perovskite interface in nano‐scale. Finally, the target flexible devices (1.01 cm2) deliver a superior efficiency of 18.12% with improved air atmosphere stability. This multi‐scale defect repair strategy provides an integrated design concept of homogeneity and stability for scalable and flexible PSCs. [ABSTRACT FROM AUTHOR]

Precise self-assembly of colloidal particles is crucial for understanding their aggregation properties and preparing macroscopic functional devices. It is currently very challenging to synthesize and self-assemble super-uniform covalent organic framework (COF) colloidal particles into well-organized multidimensional superstructures. Here, simple and versatile strategies are proposed for synthesis of super-uniform COF colloidal particles and self-assembly of them into 1D supraparticles, 2D ordered mono/multilayers, and 3D COF films. For this purpose, several self-assembly techniques are developed, including emulsion solvent evaporation, air-liquid interfacial self-assembly, and drop-casting. These strategies enable the superstructural self-assembly of particles of varying sizes and species without any additional surfactants or chemical modifications. The assembled superstructures maintain the porosity and high specific surface area of their building blocks. The feasibility of the strategies is examined with different types of COFs. This research provides a new approach for the controllable synthesis of super-uniform COF colloidal particles capable of self-assembling into multidimensional superstructures with long-range order. These discoveries hold great promise for the design of emerging multifunctional COF superstructures., (© 2024 Wiley‐VCH GmbH.)

A comprehensive study to develop and create standard samples of the zeta potential unit of particles in a liquid in accordance with the requirements of GOST ISO 13099-2-2016 in the range of measured values from –150 mV to +150 mV was carried out. The existing standard samples of the zeta potential in Russia and the world have been investigated; an analysis of the applicability of the starting materials and components for the creation of new standard samples is given. Samples based on modified polystyrene latex microspheres, bovine serum albumin and supramolecular systems based on aqueous solutions of L-cysteine, N-acetylcysteine, and silver acetate are considered as promising standard samples of the zeta potential of particles. All studies were carried out on equipment from the State Primary Standard of dispersed parameters of aerosols, suspensions and powder materials, GET 163-2020, by electrophoretic light scattering and pH measurement. It was found that polystyrene latex microspheres do not meet the requirements of the task in terms of developing a set of standard samples. Samples based on suspensions of bovine serum albumin do not meet the requirements of GOST ISO 13099-2-2016. Supramolecular systems based on aqueous solutions of L-cysteine, N-acetylcysteine, and silver acetate are proposed as standard samples. Such systems are characterized by the ability to modify the initial potential-determining layer of particles without changing their aggregate stability. Studies of the long-term stability of the developed standard samples of the zeta-potential unit of particles in a liquid have been carried out. [ABSTRACT FROM AUTHOR]

In this study, phase separation of colloidal whey protein isolate (WPI) particle dispersions was studied using a rod-like polysaccharide xanthan. Effects of different xanthan concentration, particle volume fraction, and temperature were analyzed by visual observations, turbidity measurements, and particle mobility tracking method. Particle mobility was determined using a diffusing wave spectroscopy (DWS) set up. Xanthan concentration was kept low in order not to increase the viscosity of dispersions, so that the phase separation could be observed easily. Visual observations showed that there was a minimum concentration of xanthan to induce phase separation at a constant particle volume fraction, and xanthan concentration was found to have an important effect on the degree of phase separation. The temperature was also found to have an effect on depletion mechanism. Phase separation was mainly a result of different sizes of WPI particles, and xanthan induced the depletion interaction between WPI particles, as supported by the data obtained from DWS. The results of this study explained both the mechanism and the stability range of particle dispersions in the presence of xanthan, which is important for the design of stable systems, including colloidal particles. [ABSTRACT FROM AUTHOR]

Summary: Big eye tuna head soups with different colloidal particle sizes were prepared through various filtration ways, and their antioxidative capacities and lipidomics profiling were evaluated. The original soup (OGS) (filtrated by gauze) had the highest antioxidative activities in chemical evaluation methods. Meanwhile, OGS and microfiltration soup (MFS) (micro filtrated by 0.45 μm membrane) showed higher cellular antioxidant activities (CAA) at 20 and 40 times dilution of soup, and ultrafiltration soup (UFS) (100 ku ultrafiltration) has stronger CAA at low dilution ratios (5 and 10 times) in HepG2 cells. There were 631 lipid molecular species detected in the soup, and eicosapentaenoic and docosahexaenoic acid (EPA and DHA) were mainly attached in phosphatidylethanolamine (PE) and phosphatidylcholine (PC) molecules, respectively. Based on the results, a speculation that the lipid molecule profile, especially the distribution of EPA/DHA in different lipid molecules, might contribute to the diversities of size of self‐assembled colloidal particles and antioxidative activities was concluded in this study. [ABSTRACT FROM AUTHOR]

The co-transport of pollutants with colloidal particles to lower depths of groundwater and porous environments has been demonstrated in many studies in recent three decades. Despite the numerous researches, all experimental and numerical studies of pollutant transfer in the presence of colloidal particles have been carried out in one dimension, which causes significant errors in this phenomenon. In this study, the two-dimensional transfer experiment of chromium in the presence of bentonite colloidal particles is done in saturated porous media. In order to conduct the experiment in two-dimensional conditions, the sampling was done in central and lateral of the last experiment column section. The results have been demonstrated that the transmission along the longitudinal direction is higher than lateral in the three tests of the transfer of chromium, bentonite, and chromium in the presence of bentonite colloidal particles at the beginning of the experiment, and due to completed mixing in the section, it reached to a constant value as lateral samples. While the presence of bentonite colloidal particles facilitates the transfer of chromium in both longitudinal and lateral directions, increasing the bentonite colloidal particle concentration causes more getting stuck of colloid particles between the sand grains and reduction of the chromium transfer in both longitudinal and lateral directions. So, it can be concluded that transfer in the lateral direction is lower in bentonite colloidal particles compared with chromium, and the reason is the bentonite colloidal particles getting stuck between sand grains, which is exacerbated by increasing the concentration of the bentonite. Also, due to the chromium co-transport with colloid particles in the fraction of chromium total transport, increasing the bentonite concentration causes decreasing the chromium lateral transfer. [ABSTRACT FROM AUTHOR]

Curcumin is a polyphenolic compound found in turmeric (Curcuma longa) rhizome that has potential biological benefits, including antioxidant, antimicrobial, anti-inflammatory, and anti-cancer activity. Incorporation of curcumin into functional food and beverage products, however, is challenging due to its low water-solubility, poor chemical stability, rapid metabolism, and low oral bioavailability. Researchers are, therefore developing a suite of particle-based delivery systems to maximize the potential health benefits of curcumin. Colloidal delivery systems, such as micelles, microemulsions, nanoemulsions, emulsions, solid lipid nanoparticles, nanostructured lipid carriers, biopolymer nanoparticles, and microgels have all been developed for this purpose. The functional performance of each of these delivery systems depends on its structure and physicochemical properties, such as particle composition, particle size, morphology, physicochemical stability, optical properties, rheology, and sensory attributes. As a result, each delivery system has its advantages and disadvantages for particular applications. Consequently, a delivery system must be specifically designed for the particular bioactive agent to be encapsulated, as well as the particular food matrix it will be incorporated into. In this review, we highlight the potential of the Delivery by Design (DbD) approach for identifying and selecting the most appropriate colloidal delivery system for a particular food application, using curcumin as a model bioactive agent. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • MW-dependent adsorption fractionation of NOMs on ferrihydrite colloids was studied. • HMW-NOM exhibited higher adsorption capacity than the bulk and LWM-counterparts. • Different fluorescent components exhibited different MW-dependent adsorption affinity. • An enhanced aromaticity in residual solutions was observed during adsorption. • Preferential adsorption of carbohydrates and aliphatic accounted for the enhanced aromaticity. Abstract Natural organic matter (NOM), a heterogeneous mixture with various organic components and continuous molecular weight (MW) distribution, is omnipresent in natural waters. To date, understanding of the MW-dependent adsorption fractionation of NOM samples on colloids is limited due to the lack of NOM fractionation and characterization methods. In this study, the ultrafiltration technique was applied to fractionate the bulk NOM samples into low MW (LMW-, <1 kDa) and high MW (HMW-, 1 kDa–0.45 μm) fractions, whose adsorption behaviors on ferrihydrite colloids were comparatively examined via using total organic carbon, chromophoric, fluorescent emission-excitation matrix-parallel factor (EEM–PARAFAC), and two dimension FTIR correlation spectroscopy (2D–FITR–COS). The adsorption behaviors of all samples can be reasonably explained by Langmuir and Frendlich isotherm models, and the HMW-NOM exhibited higher adsorption capacities and affinities (4.71 mg-C/g) than the bulk (3.88 mg-C/g) and LMW- (2.44 mg-C/g) counterparts. Irrespective of MWs, the non-aromatic moieties were preferentially adsorbed by ferrihydrites, causing an enhanced aromaticity for the residual solutions. Two humic-like and one protein-like component were identified by EEM–PARAFAC, and a increase and decrease trend of K a (adsorption affinity) were observed for humic- and protein-like components, respectively, in the order of LMW-, bulk, and HMW-NOM, showing obvious MW- and component-dependent adsorption fractionation of NOM on ferrihydrite colloids. 2D–FTIR–COS provided further information that, with increasing site limitation, the C–O in carbohydrate was adsorbed prior to the amide I in proteins, which testified the MW-dependent adsorption fractionation of NOM samples and accounted for the enhanced aromaticity in the residual solutions. This study highlighted the importance of MWs in NOM adsorption, which can enhance our understanding of the biogeochemical cycles of colloids and contaminants in aquatic environments. [ABSTRACT FROM AUTHOR]

The presence of retained colloidal particles causes the retardation of contaminant transport when the contaminant is favorably adsorbed to colloidal particles. Although the particle size distribution affects the retention behavior of colloidal particles, the impact of particle size distribution on contaminant transport has not been reported to date. This study investigates the impact of the particle size distribution of the colloidal particles on contaminant transport through numerical simulation by representing the particle size distribution as a lognormal distribution function. In addition, the bed efficiency and contaminant saturation of simulated breakthrough curves were calculated, and a contaminant transport model with the Langmuir isotherm for the reaction between the contaminant–sand and contaminant–colloidal particle was introduced and validated with experimental data. The simulated breakthrough curves, bed efficiency, and contaminant saturation indicated that an increase in the mean and standard deviation of the particle size distribution causes the retardation of contaminant transport. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A 120-nm silica suspension was permeated through a porous polyethylene (PE) hollow-fiber membrane, as was a solution of deformable elastic particles of poly(N-isopropylacrylamide) (PNIPAM) gel and dextran. The amount adsorbed and flux of permeation were analyzed with ordinary differential equations to obtain adsorption coefficients, maximum amounts adsorbed, and pore-narrowing factors. The thickness of the “silica-deposited layer” on the membrane was 1 μm. In a batch adsorption mode, 5.0 mg of PNIPAM gel and 30 mg of dextran were adsorbed on the PE membrane, with no adsorption on the silica. The PE membrane pores were narrowed by a secondary layer of adsorbed PNIPAM gel. When filtered through the silica-deposited layer, PNIPAM gel occupies gaps, resulting in a reduced permeation flux. Dextran passed through the silica-deposited layer and was partially adsorbed on the PE membrane. The modified membrane can control adsorption, filtration, and flux permeation, which leads to dynamic membrane separations.

It is known that coatings produced by electrodeposition, cured at high temperatures (180ºC and above).The aim of this study is reducing the energy intensity of production of polymer coatings, improving physical, mechanical properties of the polymer coatings and expansion of colors of paints for the electrodeposition. As the object of study was chosen lacquer KCh-0125, the main component of which is maleated polybutadiene. A micelle of film-forming neutralized tertiary amine is a colloidal particle size of 40 to 70 nm. One of the most effective and lowcost ways to the above problems is the introduction of the water-based oligomeric compositions hydrophobic modifiers. As modifiers were selected naturally occurring metalloporphyrins - cobalt (II) complex of pheophytin a (СоPh) and copper (II) complex of methylpheophorbide a (CuMPP). The method of introduction of the СоPh and the CuMPP of the water-based compositions for electrodeposition was developed. Colloid-chemical properties of the resulting compositions were studied. It was presented the most probable structure of the scheme colloidal particles modified by metalloporphyrins. It was conducted viscometric, spectral studies; the method of dynamic light scattering was used to determine the zeta potential and the size of colloidal particles. It was demonstrated high catalytic activity of metal complexes of porphyrins examined in structuring processes electrodeposited coatings when cured. Introduction of metalloporphyrins in the coating helps to reduce the curing temperature to 160°C. This makes it possible to reduce or duration, or a temperature curing coatings. The introduction of CuMPP make possible to obtain transparent coatings emerald green. Modified electrodeposited coatings also have good water and salt resistance.