Sonication Research Articles

Manufacturing Aluminum-Based Nanocomposites via Stir-Squeeze Casting Combined with Ultrasonication

This study successfully produced aluminum nanocomposites using a stir-squeeze casting process, both with and without ultrasonication (US) assistance. The matrix material utilized was scrap automobile wheel aluminum alloy (A356), with 1% SiC nano particles, averaging a size of 40 nm, serving as the reinforcement material. A comparison was made by also producing A356 aluminum casts with and without the use of US. The produced casts underwent thorough chemical and mechanical characterization, including optical and scanning microscopy, porosity measurement, hardness measurement, compression and tensile testing, as well as wear testing. Additionally, energy-dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) analyses were conducted to assess compositions and confirm the presence of SiC nano particles in the aluminum matrix. Porosity levels were slightly higher in the nanocomposite samples compared to pure matrix samples, attributed to the tendency of pore formation due to improper distribution of ceramic particles, resulting in clustering and agglomeration. However, significant reduction in porosity was observed with the application of ultrasonication, effectively breaking up clusters and agglomerations of reinforcement particles. Regarding mechanical properties, the A356+SiC sample with US exhibited the highest hardness (70.8 HRB), tensile strength (163.25 MPa), and compressive strength (387.2 MPa), along with the lowest abrasive wear loss (0.0017 g) among all types of casts produced in this study.

New Materials from the Integral Milk Kefir Grain Biomass and the Purified Kefiran: The Role of Glycerol Content on the Film’s Properties

Microbial exopolymers are gaining attention as sources for the development of biodegradable materials. Milk kefir, a fermented dairy product produced by a symbiotic community of microorganisms, generates milk kefir grains as a by-product, consisting of the polysaccharide kefiran and proteins. This study develops two materials, one from whole milk kefir grains and another from purified kefiran. Film-forming dispersions were subjected to ultrasonic homogenisation and thermal treatment, yielding homogeneous dispersions. Kefiran dispersion exhibited lower pseudoplastic behaviour and higher viscous consistency, with minimal effects from glycerol. Both films exhibited continuous and homogeneous microstructures, with kefiran films being transparent and milk kefir films displaying a yellowish tint. Analysis revealed that milk kefir films comprised approximately 30% proteins and 70% kefiran. Kefiran films demonstrated stronger interpolymeric interactions, as evidenced using thermogravimetric and mechanical tests. Glycerol increased hydration while decreasing thermal stability, glass transition temperature, elastic modulus, and tensile strength in both films. However, in kefiran films, elongation at the break and water vapour permeability decreased at low glycerol content, followed by an increase at higher plasticiser contents. This suggests an unusual interaction between glycerol and kefiran in the absence of proteins. These findings underscore differences between materials derived from the whole by-product and purified kefiran, offering insights into their potential applications.

Drying of avocado peels using carbonation-ultrasonication as pretreatment: energy consumption, antioxidant capacity and rheological properties

Fruit processing by-products, especially peels are underused and mostly discarded as waste. The aim of this study was to assess the effect of ultrasonication (US) combined with carbonation (CUS) on the convective drying process of avocado peels at different temperatures, adding value to this waste. For this, the avocado peels were treated with dry ice for 15 min and subjected to US (400W/10 min, 30°C) before convective air drying (50-70°C). The energy consumption, antioxidant capacity, water adsorption isotherms, rehydration rate, and dynamic rheology of dried avocado peels pretreated by CUS were compared with a control process (without pretreatment) and only US pretreatment. The combined treatment (CUS70) resulted in a 2.6-fold reduction in drying time and a 2.3-fold decrease in energy consumption, with CO2 preserving bioactive compounds and antioxidant capacity after the drying process. Differences were also observed in the rehydration capacity of the samples (CUS), with an increased water absorption capacity, along with a reduction in the viscoelastic properties of the peels. The results present new perspectives for the application of CUS in the food industry, paving the way for the development of creative, innovative, and simple approaches for the management and recycling of agri-food waste, with the potential to extend this knowledge to new food matrices.

Preparation and characterization of oat hulls-filled-sodium alginate biocomposite microbeads for the effective adsorption of toxic methylene blue dye

In this work, the performance of oat hull-filled sodium alginate (SA-O) biocomposite microbeads in the adsorptive removal of methylene blue (MB) dye was examined. First, oat hulls were pulverized and biocomposite gels containing different weight ratios of oat hulls (10 %, 20 %, and 30 %, concerning the SA amount) were prepared by dispersing them in SA solution by ultrasonic homogenization method. Finally, gels were cross-linked by dropping into a 2 % CaCl2 solution. The study revealed that the optimal adsorbent dosage was 0.025 g/50 mL, pH was roughly 6–8, and the contact time was 120 min. According to isotherm models, the non-linear Sips and Langmuir model was more appropriate compare to other isotherms from error analysis, with a maximum adsorption capacity of 687.65 mg/g and 757.57 mg/g at 298 K, respectively. Furthermore, the non-linear kinetic data and error analyzes demonstrated that the process followed the pseudo-second-order kinetic. The adsorption process was exothermic (∆H°=−17.71 kJ/mol) and spontaneous (∆G°=−26.23 kJ/mol) at 298 K, based on thermodynamic characteristics. Furthermore, reusability investigations demonstrated that the adsorbent retained its performance with no major changes in characteristics. This work reveals that highly efficient, low-cost, sustainable, and eco-friendly SA-O composites with properties might be useful adsorbents for cationic dye adsorption.

Optimizing Heat Transfer in Heat Pipes Using Hybrid Nanofluids With Multi‐Walled Carbon Nanotubes and Alumina

ABSTRACTThis study investigates the thermal performance of heat pipes using hybrid nanofluids composed of multi‐walled carbon nanotubes (MWCNT) and aluminum oxide (Al2O3) nanoparticles. The aim was to assess the effects of nanoparticle concentration (0.1%–0.5%), filling ratio (60%–90%), heat input (50–80 W), and inclination angle (0°–90°) on thermal resistance and heat transfer coefficient (HTC). Hybrid nanofluids were prepared using ultrasonic homogenization, and their stability was confirmed by zeta potential analysis, showing a reduction from −60 to −48 mV over 30 days. Experimental results revealed that the thermal resistance decreased with increasing filling ratio and inclination angle, reaching a minimum of 0.80 K/W at a 90° angle, 90% filling ratio, and 80 W heat input. Similarly, the overall HTC increased with these parameters, peaking at 2250 W/m2 K under the same conditions. At a 0.5% nanoparticle concentration, the HTC improved by up to 40% compared with conventional fluids. The thermal conductivity of the hybrid nanofluid also rose significantly, from 0.7 W/m K at 30°C to 1.5 W/m K at 90°C, outperforming distilled water. These findings highlight the potential of hybrid nanofluids to enhance heat pipe efficiency, particularly in high‐power applications, by optimizing nanoparticle concentration, filling ratio, and inclination angle.

Cell Disruption and Hydrolysis of Microchloropsis salina Biomass as a Feedstock for Fermentation

Microalgae are a promising biomass source because of their capability to fixate CO2 very efficiently. In this study, the potential of Microchloropsis salina biomass as a feedstock for fermentation was explored, focusing on biomass hydrolysis by employing various mechanical and chemical cell disruption strategies in combination with enzymatic hydrolysis. Among the mechanical cell disruption methods investigated on a lab scale, namely ultrasonication, bead milling, and high-pressure homogenization, the most effective was bead milling using stainless-steel beads with a diameter of 2 mm. In this way, 87–97% of the cells were disrupted in 40 min using a mixer mill. High-pressure homogenization was also effective, achieving 86% disruption efficiency after four passes on a 30–200 L scale using biomass with 15% (w/w) solids content. Enzymatic hydrolysis of the disrupted cells using a mixture of cellulases and mannanases yielded up to 25% saccharification efficiency after 72 h. Acidic hydrolysis of undisrupted cells followed by enzymatic treatment yielded around 30% saccharification efficiency but was coupled with significant dilution of the resulting hydrolysate. Microalgal biomass hydrolysate produced was determined to have ~8.1 g L−1 sugars and 2.5% (w/w) total carbon, as well as sufficient nitrogen and phosphorus content as a fermentation medium.

The Impact of Homogenization Techniques and Conditions on Water‐In‐Oil Emulsions for Casein Hydrolysate–Loaded Double Emulsions: A Comparative Study

ABSTRACTThis study aims to evaluate homogenization techniques and conditions for producing stable, small droplet‐size water‐in‐oil (W/O) emulsions intended for incorporation into casein hydrolysate–loaded double emulsions. Three commonly used homogenization methods; rotor–stator, ultrasonic, and high‐pressure homogenization were individually optimized utilizing response surface methodology. Instances of over‐processing were observed, particularly with the rotor–stator and ultrasonic homogenizers under specific conditions. Nevertheless, optimal conditions were identified for each technique: 530 s at 17,800 rpm agitation speed for the rotor–stator homogenizer, 139 s at 39% amplitude for the ultrasonic homogenizer, and 520 s at 1475 bar for the high‐pressure homogenizer. Subsequently, the W/O emulsions produced under optimal conditions and their respective W1/O/W2 double emulsions were compared. The rotor–stator and high‐pressure homogenized W/O emulsions exhibited comparable narrow droplet‐size distributions, as indicated by similar Span values. However, high‐pressure homogenization failed to sufficiently minimize droplet size. Ultrasonic homogenization resulted in droplets at the 1‐μm scale but yielded more polydisperse droplet‐size distribution. According to TOPSIS analysis, an emulsion with a viscosity of 93.1 cP (centiPoise), a stability index of 93.8%, a D(90) of 0.67 μm (0th day), and a D(90) of 0.75 μm (30th day) produced using a rotor–stator was selected. Additionally, double emulsions containing primary emulsions prepared with the rotor–stator method demonstrated higher viscosity, narrower droplet‐size distribution, and lower creaming compared to other samples. This investigation sheds light on the influence of homogenization techniques on emulsion properties, providing valuable insights for optimizing double emulsion formulations.

Impact of ultrasonic probe type, frequency, and static pressure on large-scale graphene exfoliation

The ultrasonic liquid phase exfoliation method has emerged as an essential research direction for graphene preparation due to its cost-effectiveness and ability to minimize defects. However, this method faces challenges related to processing throughput when scaled up for industrial production. In this study, industrial grade ultrasonic homogenizers with different frequencies and probe types were evaluated for the preparation of FLG. In each experiment, 1.5 kg of graphite slurry was treated using a cyclic ultrasonic system. The results demonstrated that the 25 kHz dumbbell probe produced the thinnest FLG with the lowest defect density. Moreover, applying a static pressure of 0.2 MPa in the cycle system enhanced the cavitation-induced exfoliation of graphite sheets, effectively reducing the layer count and distribution range of FLG. This method improves the conductivity while minimizing defect density.

Cellulose nanocrystal extraction from tissue paper wastes using different extraction methods and cellulose acetate production

ABSTRACT This paper examines the feasibility of extracting cellulose from tissue paper wastes (TPW’s) using several methods: sonication (SC), subcritical (SU), microwave (MC), and microwave with diluted acid (MA). The chemical characterisation and morphological properties of nanocrystal cellulose were investigated using Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and scanning electron microscopy with energy dispersive X-Ray analysis (SEM-EDX). TPW’s have a relatively high crystallinity index (CrI = 61.02%). It was found to be lower than that for cellulose extracted using SU and SC MC, MA methods, where CrI to 65.65%, 68.07%, 69.21% and 73.42%, respectively. The MA method yielded cellulose with the highest CrI and altered surface morphology. This cellulose was selected for cellulose acetate synthesis. After acetylation, the CrI decreased to 61.45%, and the morphological aspect was changed. In conclusion, nanocrystal cellulose was successfully extracted from TPW’s and effectively changed to its esterified form.

A comparative study on sequential green hybrid techniques (ultrasonication, microwave and high shear homogenization) for the extraction of date seed bioactive compounds and its application as an additive for shelf-life extension of Oreochromis niloticus

This study focuses on the extraction of bioactive compounds from date seeds using five polyol-based deep eutectic solvents (P-DESs) in combination with hybrid green extraction techniques, specifically microwave-assisted extraction (MAE), homogenization-assisted extraction (HAE), and ultrasound-assisted extraction (UAE). The optimization of these extraction techniques was achieved using P-DESs showing the highest efficiency for extracting date seed bioactive compounds using response surface methodology (RSM) and central composite design (CCD) approach. The optimized conditions from three green techniques were further applied in the form of hybrid green extraction techniques, involving six binary and three ternary methods, to assess the percentage increase in the extraction efficiency of date seed bioactive polyphenolics. Among the five P-DESs tested, choline chloride: ethylene glycol (ChCl:Eg) exhibited the highest extraction efficiency for recovering date seed phenolic compounds. Using ChCl:Eg as the P-DES, the highest extraction efficacy was found with MAE, followed by > HAE and > UAE. In addition, all hybrid extraction techniques showed higher extraction efficiencies than the single extraction methods. Notably, the binary hybrid techniques combining UAE and MAE (UMAE), HAE and MAE (HMAE) resulted in significantly higher recovery of bioactive compounds, with 52 % and 49 % increases in total phenolic content, respectively, compared to single extraction techniques. The lowest MIC and MBC of P-DES (ChCl:Eg) and date seed P-DES based extract recorded against all the tested bacterial strains was 40 % and 20 % respectively. Furthermore, the date seed extract from MAE was used to extend the shelf life of Oreochromis niloticus stored at 4 °C for 10 days. The results indicated that the date seed polyphenolic extract effectively inhibited microbial growth in Oreochromis niloticus during refrigerated storage, with the total bacterial count (TBC) of all the treated samples within the recommended acceptability limit of < 6 log CFU/g compared to the untreated samples, which showed a total bacterial count (TBC) > 6 log CFU/g. This study demonstrated that sequential hybrid techniques enhance and intensify the recovery of bioactive compounds more effectively than any single green technique.

Combating foodborne pathogens: Efficacy of plasma-activated water with supplementary methods for Staphylococcus aureus eradication on chicken, and beef

The research study suggested using plasma-activated water (PAW) along with auxiliary technologies, such as micro/nanobubbles (MNB), ultraviolet (UV) photolysis, and ultrasonication (US), to increase the effectiveness of sterilization. By using Factorial Design of Experiments (DOE) techniques, the characteristics and optimal production that contributed to disinfecting pathogens were assessed. Analysis revealed that Staphylococcus aureus (S. aureus) infection rate was most significantly influenced by factors including duration of MNB, UV, and the interaction term between MNB*UV. The optimal conditions for S. aureus reduction in chicken and beef of 8.41 and 8.20 log10 CFU/ml, respectively, which were found when PAW was combined with UV and US for 20 min of treatment. This study arrives to the conclusion that combining PAW with appropriate supplementary technologies increased efficiency and enhance disinfection effectiveness in chicken and beef which could be implemented for another alternative pathogen inactivation in food industry.© 2017 Elsevier Inc. All rights reserved.

Improvement of Electrical and Thermal Properties of Carbon Nanotube Sheets by Adding Silver Nanowire and Mxene for an Electromagnetic-Interference-Shielding Property Study.

Hybrid carbon nanotube (CNT) sheets were fabricated by mixing CNTs with silver nanowires (AgNWs) and MXene to study their electromagnetic-interference (EMI)-shielding properties. CNT/AgNW and CNT/MXene hybrid sheets were produced by ultrasonic homogenization and vacuum filtration, resulting in free-standing CNT sheets. Three different weight ratios of AgNW and MXene were added to the CNT dispersions to produce hybrid CNT sheets. Microstructure characterization was performed using scanning electron microscopy, and the Wiedemann-Franz law was used to characterize transport properties. The resulting hybrid sheets exhibited improved electrical conductivity, thermal conductivity, and EMI-shielding effectiveness compared to pristine CNT sheets. X-band EMI-shielding effectiveness improved by over 200%, while electrical conductivity improved by more than 1500% in the hybrid sheets due to a higher charge-carrier density and synergistic effects between nanomaterials. The addition of AgNW to CNT sheets resulted in a large improvement in electrical conductivity and EMI shielding; however, this may also result in increased weight and sample thickness. Similarly, the addition of MXene to CNT sheets may result in an increase in weight due to the presence of the denser MXene flakes.

Ultrasound-assisted solvent extraction of phenolics, flavonoids, and major triterpenoids from Centella asiatica leaves: A comparative study

Centella asiatica has been known for its significant medicinal properties due to abundance of bioactive constituents like triterpenoids and flavonoids. Nevertheless, an appropriate solvent system and extraction technique is still lacking to ensure optimized extraction of bioactive constituents present in C. asiatica. Recently, scientists are more focused towards application of green sustainable extraction techniques for the valuable components from plant matrix owing to their eco-friendly and safe nature. Among these, ultrasonication (US) is known as a valuable strategy for separation of bioactive components from medicinal plants. Hence, current research was performed to observe the effect of ultrasonication in the presence of five different solvents (Water, Hexane, Methanol, Chloroform, and Ethyl acetate) on total phenolic contents (TPC), total flavonoid contents (TFC), antioxidant properties (DPPH, ABTS, Nitric oxide radical activity, and Superoxide anion assay), and four major triterpenoid contents in C. asiatica leaves. Herein, ultrasound assisted methanolic extract (UAME) possessed maximum amount of TPC (129.54 mg GAE/g), TFC (308.31 mg QE/g), and antioxidant properties (DPPH: 82.21 % & FRAP: 45.98 µmol TE/g) followed by ultrasound-assisted Water extract (UAWE), ultrasound-assisted ethyl acetate extract (UAEAE), ultrasound-assisted n-hexane extract (UAHE), and ultrasound-assisted chloroform extract (UACE), respectively. Moreover, the superoxide radical and nitric oxide assays depicted a similar trend, revealing the highest percent inhibition for UAME (SO: 83.47 % & NO: 66.76 %) however, the lowest inhibition was displayed by UACE (63.22 % & 50.21 %), respectively. Highest content of major terpenoids were found in UAME of C. asiatica leaves as madecassoside (8.21 mg/g) followed by asiaticoside (7.82 mg/g), madecassic acid (4.44 mg/g), and asiatic acid (3.38 mg/g). Ultrasound-assisted extraction technique can be an efficient extraction method for bioactive compounds present in C. asiatica. However, ultrasonication along with methanol as an extraction solvent can surely enhance the extraction of valuable constituents. The results of this study provide an insight into major terpenoids, and antioxidants present in extracts of C. asiatica, implicating its use in ancient medicine systems and future drug development.

Method development and validation for the extraction and quantification of sesquiterpene lactones in Dolomiaea costus

Dolomiaea costus, commonly known as Indian costus, is a medicinal plant from the Asteraceae family. The root and powder of costus have been widely used to treat various health conditions. The primary bioactive compounds in this plant are sesquiterpene lactones, particularly costunolide and dehydrocostus lactone. This study aimed to establish a rapid, environmentally friendly, and cost-effective method for the high-throughput extraction and quantification of sesquiterpene lactones in Indian costus. Ultrasonic bath (UB) and UPLC/MS-MS were employed to extract and analyse 49 Indian costus samples. Aqueous ethanol was identified as the most effective solvent system for extracting and analysing sesquiterpene lactones. The extraction efficiency of the ultrasonic bath was comparable to that of the ultrasonic homogeniser while shaking showed the lowest efficiency. The environmentally friendly UPLC/MS-MS analysis revealed mean concentrations (±SD; μg/100 μg) of 1.00 (±0.39) for costunolide and 0.70 (±0.25) for dehydrocostus lactone. An inverse correlation was observed between sesquiterpene lactone content and sample colour. Most samples contained costunolide levels above the minimum limit (0.6 %) specified by the Chinese monograph, but only a few met the 1.8 % threshold for total sesquiterpene lactones. Given the importance of bioactive sesquiterpene lactones for medicinal efficacy, insufficient levels may result in diminished therapeutic value. Therefore, standardising Indian costus products is crucial to ensure quality and appropriate dosing. This study contributes to the standardisation of Indian costus, a vital step towards ensuring the efficacy and safety of herbal products.

Combining Ultra-Turrax and ultrasonic homogenization to achieve higher vitamin E encapsulation efficiency in spray drying

Vitamin E, a soluble antioxidant widely used in the food and pharmaceutical industries, is rich in tocopherols and phytosterols. Since vitamin E molecules are highly sensitive to oxidation, encapsulation is a viable and effective technique for preservation of the properties of Vitamin E and improving its stability during storage, maintaining the nutritional value. In this work, the aim was to encapsulate concentrated vitamin E using a combination of Ultra-Turrax and ultrasonication to achieve higher encapsulation efficiency in spray drying. In the first stage, the vitamin E oil was encapsulated employing only Ultra-Turrax homogenization, with subsequent optimization of spray drying. The coating materials used were maltodextrin and whey protein isolate. Optimization of the spray drying step evaluated the effects of the drying air temperature (T) and the feed flow rate (Q), to obtain better yields and a high-quality product. In the second stage, the use of ultrasonication in an additional homogenization step was evaluated, aiming to further improve the encapsulation process. The results showed that the best drying conditions (first stage) were T = 180 °C and Q = 0.6 L/h, which provided the highest yield (67.73%) and high encapsulation efficiency (73.73%). The microspheres produced had similar properties, with mean diameters ranging from 0.64 to 12.99 μm. In the second stage of the investigation, the application of ultrasonication immediately after the Ultra-Turrax homogenization enabled the encapsulation efficiency to be increased to 94.05%, with a yield of 57.54%, using an ultrasonication time of only 7 min. This showed that addition of the ultrasonic homogenization step to the process greatly improved the encapsulation efficiency and could be used to produce vitamin E-enriched powder microcapsules by spray drying, with application in the food industry.

Microstructure refinement, mechanical performances and degradability of biomedical Zn-2Cu alloy by ultrasonic melting and homogenization treatment

Zn alloys are deemed to be desired body implant materials because of their moderate degradation rate. In this paper, the microstructural evolution, mechanical performances, and degradability of Zn-2Cu alloy prepared by ultrasonic melt treatment (UMT) with different ultrasonic powers (0 W, 300 W, 600 W, and 900 W) were systematically studied. Under the condition of UMT, the coarse α-Zn grains of Zn-2Cu alloy were refined into fine equiaxed grains and the mean size was significantly decreased from 133.4 μm to 65.3 μm when the ultrasound power was enhanced. The precipitating CuZn5 phase was significantly refined from the coarse block into the spherical shape. Moreover, the fraction of the CuZn5 precipitates of the Zn-2Cu alloy was greatly reduced with the increase of ultrasonic power. Tensile tests showed that the ultimate tensile strength (UTS), yield strength (YS), and elongation (El) of Zn-2Cu alloy were remarkably enhanced to 203 MPa, 167 MPa, and 8.14 %, respectively, when the Zn-2Cu alloy melting was treated by 600 W power. It was found by electrochemical polarization test that the degradation rate of Zn-2Cu alloy treated by UMT with 0 W, 300 W, 600 W, and 900 W power in Hank’s solution was gradually decreased to 1.6312 mm/a, 1.3206 mm/a, 1.0992 mm/a, and 1.2832 mm/a, respectively. In addition, after the Zn-2Cu alloys were immersed in Hank’s solution for 30 days, the degradation rate of samples was summarized as 0 W alloy (0.472 mm/a) > 300 W alloy (0.436 mm/a) > 900 W alloy (0.412 mm/a) > 600 W alloy (0.398 mm/a). The studies verified that the UMT was a very valuable technology for preparing Zn-2Cu alloy, which can meet the requirement of mechanical properties and degradable rate as a promising implant material.

Experimental investigation of the compressive behavior of epoxy nanocomposites reinforced with straight and helical carbon nanotubes

AbstractThis paper is aimed at an experimental investigation of the effect of straight and helical carbon nanotubes on the compressive behavior of epoxy nanocomposites. The epoxy nanocomposites are fabricated with varying levels of SCNT and HCNT, each with two different fabrication techniques viz. high shear mixing and ultrasonication. In samples made using high shear mixing, the compressive strength is found to actually decrease, due to poor dispersion of the CNTs, resulting in voids and clumps, which can adversely affect the strength. Ultrasonic homogenization is found to better disperse the CNTs within the epoxy resin with nearly a 10‐fold decrease in the heterogeneity size. Compression tests conducted on the ultrasonically homogenized CNT‐epoxy nanocomposites indicate a modest increase in the compressive strength. The best increase of 5% is obtained with 1% SCNT. On the other hand, the HCNT samples show a higher post‐peak residual stress suggesting an improved mode II/III fracture toughness. The high shear mixed samples exhibit a bulging deformation with no clear evidence of shear localization. On the other hand, the ultrasonic homogenization (UH) samples bulge and eventually show a clear localized shear band, likely due to a smaller heterogeneity size. Some samples with relatively poor dispersion exhibit an axial splitting failure and a comparatively low compressive strength. In addition, it is demonstrated that using acetone as a solvent during dispersion can affect the curing kinetics, which results in a nanocomposite with a rubbery consistency with low stiffness and strength, but high deformability.Highlights Straight and helical CNTs impact the compressive behavior of epoxy nanocomposites High shear mixing reduces compressive strength due to poor CNT dispersion Ultrasonication improves CNT dispersion but modest rise in compressive strength HCNTs cause higher post‐peak residual stress suggesting higher toughness Using acetone affects curing, leading to rubbery, deformable nanocomposites.

Lotus (Nelumbo nucifera G.) seed starch: Understanding the impact of physical modification sequence (ultrasonication and HMT) on properties and in vitro digestibility

Native lotus (Nelumbo nucifera G.) seed starch (LSS) was single- and dual-modified by heat-moisture treatment (HMT), ultrasonication (US), HMT followed by the US (HMT-US), and the US followed by HMT (US-HMT). The modified lotus seed starch (LSS) was evaluated for its physicochemical, pasting, thermal, and rheological properties and in vitro digestibility. All treatments decreased the swelling power (10.52–14.0 g/g), solubility (12.20–15.95 %), and amylose content (23.71–25.67 %) except for ultrasonication (17.67 g/g, 17.90 %, 29.09 %, respectively) when compared with native LSS (15.05 g/g, 16.12 %, 27.12 %, respectively). According to the rheological study, G′ (1665–4004 Pa) was greater than G″ (119–308 Pa) for all LSS gel samples demonstrating their elastic character. Moreover, gelatinization enthalpy (17.56–16.05 J/g) increased in all treatments compared to native LSS (15.38 J/g). Ultrasonication treatment improved the thermal stability of LSS. The digestibility results showed that dual modification using HMT and US significantly enhanced resistant starch (RS) and reduced slowly digestible starch (SDS) in LSS. Cracks were observed on the surface of the modified LSS granules. Peak viscosity decreased in all modified starches except for ultrasonication, suggesting their resistance to shear-thinning during cooking, making them ideal weaning food components. The results obtained after different modifications in this study could be a useful ready reference to select appropriate modification treatments to produce modified LSS with desired properties depending on their end-use.

A facile synthesis of pectin/red clover extract nanoemulsions and nanofibers

The aim of this article was to generate pectin(P)/red clover extract (RCE) nanoemulsions (NEs) and nanofibers via a simple and short procedure for potential applications in women’s health. To that end, stock aqueous RCE NEs were prepared first in the absence and presence of a surfactant mixture consisting of 1/3 Span® 80/Tween® 80 with the help of an ultrasonic homogenizer using various processing times (0, 1, 5, and 10 min). Droplet sizes of RCE NEs were measured and statistically evaluated. The most significant factor was revealed to be the presence of surfactant mixture. The minimum droplet size (51 ± 1 nm) could be achieved by determining the ultrasonication time as 5 min in the presence of the surfactant mixture. Stock aqueous RCE NEs were exploited for preparing pectin-containing RCE NEs. Independent of the surfactant mixture, addition of pectin increased the droplet sizes substantially (372–458 nm and 509–728 nm in the absence and presence of the surfactant mixture). Neat pectin nanofibers had fiber diameters of 389 ± 87 nm. However, addition of the RCE NEs led to fiber with larger diameters (569 ± 134 nm and 763 ± 188 nm in the absence and presence of the surfactant mixture, respectively).

Functionality modulation of starch from lotus rhizome using single and dual physical modification

The effects of ultrasonication (US) assisted by pre- and post-treatment of heat-moisture treatment (HMT) on physicochemical, rheological, pasting, digestive, and thermal properties of lotus rhizome (LR) starch were investigated in this study. All treatments decreased the swelling power, amylose content, and peak viscosity except for the ultrasonicated sample when compared with native LR starch. All treatments showed similar diffraction patterns with different intensities. FTIR spectra characteristic peaks did not emerge or disappear after single and dual modifications. Storage modulus (G′) is greater than loss modulus (G″) for all LR starch gel samples demonstrating their elastic character. Moreover, ΔHgel (253.1–303.7 J/g) increased in all treatments. Dual modification (HMT & US) significantly enhanced resistant starch and reduced SDS in LR starches. These results could be beneficial for promoting ultrasound processing for potential uses in the food industry and starch production.