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This study aimed to develop a high-performance asphalt mixture resistant to rutting through modification with industrial-scale graphene nanoplatelets (industrial GNPs). To achieve this objective, industrial GNPs were incorporated into an SBS-modified asphalt binder at concentrations of 2%, 4%, 6%, 8%, and 10% by mass of the asphalt binder. The aim was to select a design content to enhance the rutting performance of the resulting asphalt mixture. The nanomaterial content selection criterion was based on apparent viscosity results and rheological parameters (MSCR). Two asphalt mixtures were produced after determining the nanomaterial content: a reference mixture and another modified by the selected content (2.64% of industrial GNPs). The mechanical performance was assessed through resistance to rutting tests on French Orniéurer equipment and, in a secondary character, the fatigue resistance under four-point bending. The results showed better rheological behaviour of the modified composites than of the original binder, decreasing the viscous response at high temperatures and thus reducing the non-recoverable deformations. The resistance to rutting of the modified mixture exceeded that of the reference mixture by 19% (mean rut for 30,000 cycles) without significant damage to the fatigue life, proving the high rutting performance of the alternative asphalt mixture. [ABSTRACT FROM AUTHOR]

BACKGROUND: The incorporation of functional food ingredients in chocolate that seek to eliminate, if not completely, most of the added sugar content, as well as the use of alternative chocolate production techniques, have gained popularity in recent years. This study aimed to incorporate red beetroot powder into dark chocolate and investigate the effect of red beetroot powder concentration and processing time in a melanger on the physicochemical properties, sensory profile and consumer acceptability of beetroot dark chocolate. RESULTS: The addition of red beetroot powder increased the moisture content, particle size distribution and hardness of the chocolates, while the opposite was true for processing time with no effect on the colour. Except for taste, which had an average score of 3.2 ± 1.8 on the 7‐point hedonic scale, consumers scored all the other sensory attributes of the chocolates above 4.0. Among the chocolates with red beetroot powder, samples with a 15% red beetroot powder addition had a high average overall acceptability score of >5, while the 30% sample scored <4. CONCLUSION: Red beetroot powder can be used to replace sugar in dark chocolate without affecting its physicochemical properties, sensory profile or consumer acceptability. However, the target market should be considered when determining the level of red beetroot powder incorporation in terms of chocolate taste. This research has the potential to improve the overall health‐promoting properties of dark chocolate by eliminating added sugar (partially or completely). It would also help to diversify beetroot utilization, allow small‐scale processors to venture into chocolate production and expand the small‐scale chocolate value chain. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

This study prepared six different ice creams to investigate the effect of yeast protein (YP) on their sensory, rheological, thermal properties and fat destabilisation. Results indicated that YP could improve sensory quality, flow and viscoelastic properties. The thermal property was also positively influenced by YP with a significant decrease in frozen water percentage and an increase in glass transition temperature (P < 0.05). Additionally, the particle size and confocal laser scanning microscopy results illustrated that YP could moderately promote the fat aggregate percentage and size. Overall, YP could serve as a fat replacer to produce reduced‐fat ice cream. [ABSTRACT FROM AUTHOR]

In this present study, a three-factor Box–Behnken, response surface methodology (RSM) design was employed to optimize the skimmed milk powder (SMP)/whey protein concentrate (WPC) ratio (0.25–0.75%w/v) as a source of milk protein, inulin (1–2%w/v), and honey (4–6%w/v) for production of high-quality goat milk yoghurt (GMY). The resulting ANOVA and response surface equations revealed the significant effect (p < 0.05) of these variables on the various attributes such as total solid (%), pH, titratable acidity [(LA) % by weight], syneresis (%), DPPH (% inhibition), viscosity (m.Pa⋅s), whiteness index (WI), and overall acceptability (OA). The coefficient of determination (R2) for all response variables ranged from 0.88 to 0.99. Lack-of-fit tests resulted in non-significant F-values. The optimal conditions were determined as SMP/WPC at 0.36%w/v, inulin at 1.00%w/v, and honey at 6.00%w/v. The optimum values for total solid, pH, titratable acidity, syneresis, DPPH, viscosity, WI, and OA were 22.03, 4.46, 0.77, 6.34, 25.20, 182.30, 76.29 and 8.37, respectively with desirability value of 0.95. [ABSTRACT FROM AUTHOR]

Nanofluids (NFs) of fascinating multifunctional properties are the advanced materials highly admired in emerging soft device technologies. In this innovative research, we explored the detailed optical, dielectric, and rheological properties of silver ions conducting green NFs. These NFs comprise ethylene glycol (EG) as viscous base fluid, suspension of a fixed amount (0.02 wt%) aluminum oxide (Al2O3) nanoparticles for high performance thermal conductor, and addition of silver nitrate (AgNO3) salt as the ionic component of varying amounts ranging from 0.2 to 2.0 wt% are prepared and investigated. The detailed analysis of 200–800 nm wavelength range ultraviolet–visible (UV–Vis) absorbance spectra of these EG–Al2O3/AgNO3 based NFs demonstrated their significant photosensitivity character in the visible region, radiations shielding performance in the UV region, and trio energy band gaps in a wide semiconducting range from 2.4 to 4.9 eV which are found adequately tunable with the AgNO3 concentrations. The high static dielectric permittivity (εs ≈ 40) of these polar NFs, at 298.15 K, showed a marginal change with the variation in AgNO3 concentrations confirming a little alteration in the parallel aligned dipole ordering of hydrogen bonded EG molecular network beside the ion-molecules-nanoparticle interactions and formation of ion-dipole complexes (coordinative interaction). The electrical conductivity of EG–Al2O3 NF increased by three orders of magnitude i.e., from 10−6 to 10−3 S/cm, at the initial addition of 0.2 wt% AgNO3 in it and then, exhibited almost a linear increase with further increasing the salt concentrations up to 2.0 wt% realizes them promising ionic nanofluids. Rheological investigations on these NF samples, at 298.15 K, validate their Newtonian behaviour with a high dynamic viscosity of 14 mPa s. These experimental findings highlight the multifunctional characteristics of EG–Al2O3/AgNO3 nanofluids which could be utilized in heat transfer, solar energy harvesting/storage, and the development of next-generation iontronic and optoelectronic devices and silver ion conducting biomedical sensors.

Natural sepiolite has great potential for application in wound healing, haemostasis and medicines. This paper introduces a versatile solid-state sintering technique for preparing sepiolite-based nanocomposites with enhanced antibacterial properties, and the physical, structural, rheological and antibacterial properties of which were determined to be enhanced. The incorporation of nanosized Ag and metal oxides into sepiolite composites results in a notable improvement in their antibacterial efficacy against Escherichia coli and Staphylococcus aureus in comparison to the unmodified sepiolite. With a low silver content of just 5%, the sepiolite–Ag composite achieves an antibacterial rate of ~100%. Furthermore, the rheological properties exhibited by the sepiolite composites are noteworthy, suggesting their suitability for use in wound-dressing applications due to their exceptional workability. The methodology employed in this research has the potential to offer a viable substitute for the production of economical and effective natural antibacterial nanocomposites. [ABSTRACT FROM AUTHOR]

In the context of growing interest in plant-based food products for their potential health benefits and sustainability, this study investigates the effect of mono- and diglycerides of fatty acids application on physico-chemical properties of various plant-based cream products, compared to lecithin application in rice cream. Rheological and textural parameters, colour profile, and colloidal stability were analysed. The application of mono- and diglycerides modified the creams' viscoelastic behaviour, showing a decrease in viscoelasticity across the samples; although in oat–coconut cream resulted in a higher viscoelasticity, indicating the formation of a gel-like structure. Rice cream with lecithin emulsifier showed lower viscoelastic properties characterised by higher phase angle (tan δ). All samples behaved as pseudoplastic materials (with a flow behaviour index n < 1). For coconut and almond creams, the consistency coefficient increased and flow behaviour index decreased after emulsifier application. Interestingly, the emulsifier addition did not significantly affect the cream's colour profile, characterised by yellow hue angle (h*) as a dominant spectral component. The colloidal stability, indicated by a stability index (SI), was determined as well. [ABSTRACT FROM AUTHOR]

The present fused deposition modeling (FDM) printing process has concentrated on combining metal or ceramic filled with polymer because it could provide a strong composite in layered manufacturing technology in comparison to a single polymer material. However, the ability of the composite material to flow into the extruder becomes an obstacle because of the changes in the polymer concentration and dispersion of filler particles in producing the printed part. Hence, the rheological behavior of Hydroxyapatites (HAp) / Polylactic Acid (PLA) composite with different contents of HAp was studied to assess its ability to flow through the extruder during the 3D printing process. Measurements such as pycnometer density, thermal analysis (DSC) and FT-IR were performed on the composite feedstock containing a variation of 10% to 30% HAp powder. The feedstocks behavior then were characterized by rheological tests at three different temperatures (140 °C, 150 °C, and 160 °C). The composition of PLA/20HAp has produced optimum rheological behavior with effective flow behavior index (n) and activation energy (E) of 0.396 and 89.03 kJ/mol, respectively which is suitable for extruding out the HAp/PLA composite to become a 3D printing filament material. [ABSTRACT FROM AUTHOR]

The lotus seed and lily bulb beverage (LLB) has a problem with solid particle sedimentation. To address this issue, LLB was homogenised twice at different pressures (0~100 MPa) using a homogeniser. This study aims to investigate the changes in the particle size distribution (PSD), microstructure, rheological behaviour, sedimentation index (IS), turbidity, physicochemical properties, and sensory quality of LLBs after homogenisation treatments. The results regarding PSD and microstructure showed that the suspended particles were decomposed at high pressure with increasing homogenisation pressure, forming small particles of cellular material, cell wall fragments, fibre fractions, and polymers. The LLB showed shear-thinning behaviour and weak gelation characteristics (G′ > G″) and rheological properties. Among all homogenisation pressures, the 60 MPa sample showed the lowest sedimentation rate and the highest turbidity. When the pressure was increased from 0 to 100 MPa, the total soluble solid (TSS) content showed an upward trend, while the ascorbic acid content (AAC) gradually decreased. The highest sensory evaluation was observed in the 60 MPa sample in terms of overall acceptability. [ABSTRACT FROM AUTHOR]

This study explores the effect of various concentrations of Xanthan gum on the rheological behaviour of commercial mayonnaise. The various concentrations of Xanthan gum, ranging from 0.1 to 0.5% based on the weight of the mayonnaise which were mixed in the commercial mayonnaise via a high overhead stirrer at room temperature. The rheological characterizations were carried out on a Brookfield viscometer. Using Mitschka's method, the recorded data was changed into rheological parameters. Three rheological models, namely the Power-law model, Bingham model and Herschel-Bulkley model, used to determine the flow parameters of the samples. All the samples showed shear thinning behaviour at least in the shear rate used in this study. According to the goodness of fit (regression coefficient), the power law model was the best for determining flow parameters. It was observed that the consistency viscosity (K) increases with an increase in Xanthan gum concentration, at least for the concentration ranges used in this research. The higher value of K indicates that the mayonnaise becomes thick with Xanthan gum and will require higher yield stress to start flow. It was interesting to note that at 0.1% Xanthan gum concentration, the power index reached a plateau value of 0.1135. [ABSTRACT FROM AUTHOR]

Dehydroabietyl polyethylene glycol glycidyl ether-grafted hydroxyethyl cellulose (HEC) polymer surfactant (DA (EO)5GE-g-HEC) was prepared using ring-opening polymerization with biobased rosin and hydroxyethyl cellulose as feedstocks. Dehydroabietyl polyethylene glycol glycidyl ether (DA(EO)5GE) was formed by condensation of dehydroabietyl alcohol polyoxyethylene ether (Rosin derivative: DA(EO)5H) and epichlorohydrin. The grafting degree of DA(EO)5GE-g-HEC was manipulated by adjusting the mass ratio of HEC and DA(EO)5GE and confirmed by EA. According to the formula, when m(HEC)/m(DA(EO)2GE) was 1:1~1:5, the grafting rate of DA(EO)5GE in DA(EO)5GE-g-HEC varied from 34.43% to 38.33%. The surface activity and foam properties of DA(EO)5GE-g-HEC aqueous solution were studied. The results showed that with the increase in grafting rate, the critical micellar concentration (CMC) in aqueous solution changed from 1.28 to 0.96 g/L. The results of the thermogravimetric analysis showed that the temperature range of the main stage of mass loss of DA(EO)5GE-g-HEC was 310°C~410°C, and the thermal decomposition processes of the samples with five mass ratios were similar. An oil in water emulsion was prepared by choosing cyclohexane as the oil phase and DA(EO)5GE-g-HEC as the emulsifier. The effect of DA(EO)5GE-g-HEC mass fraction on emulsion particle size and stability was analyzed. The results suggested that when the oil-water ratio was 8:2 with 0.4% emulsifier, the emulsion droplets were the smallest in terms of particle size and were the most stable. The rheological test results showed that the apparent viscosity decreased with the increase in shear rate and showed a typical elastic gel phenomenon. [ABSTRACT FROM AUTHOR]

Bitumen emulsion, which is widely used for surface treatment and cold recycling in pavement engineering, has the advantage of not requiring heating during construction. But it has the disadvantage of low mechanical strength, especially at higher temperatures. Various studies have proved that waterborne epoxy can effectively improve the mechanical properties of bitumen emulsion. However, how aging affects the performance of waterborne epoxy resin-modified bitumen emulsion is still unclear. This study aims to fill this knowledge gap through combined rheological and microscopic characterisation. Fourier transform infra-red spectroscopy (FTIR) was first applied to characterise the oxidative reaction during the pressure aging vessel (PAV) test. The rheological behaviours before and after PAV aging were evaluated through dynamic shear rheometer (DSR) tests. The peak force tapping quantitative nanomechanical (PFT QNM) test was further conducted to measure the micromechanical performance of the waterborne epoxy bitumen emulsion residues. The results indicated that waterborne epoxy resin could improve the resistance to oxidative aging of the emulsion residues. In addition, it was found that the complex moduli generally increased while the phase angle decreased after PAV aging, and the aging process would lead to higher micromechanical modulus and lower adhesion. [ABSTRACT FROM AUTHOR]

Synthetic esters have long been used in a variety of applications due to their excellent thermal stability, excellent cleanliness, natural lubricity, and polarity. In the present work, we aimed to prepare some synthetic base oils through preparation of different dibasic esters by esterification of dicarboxylic acids (adipic acid and azelaic acid) with different linear alcohols (hexanol, octanol, and decanol) and branched alcohol (2‐ethyl hexanol) at 120°C. The reaction yield ranges between 85% and 94%. Fourier‐transform infrared spectroscopy (FT‐IR) and proton nuclear magnetic resonance (1H‐NMR) spectroscopy were used to analyze the structures of the produced compounds. Using thermo gravimetric analysis (TGA), the heat stability of the produced esters was determined, and it was found that the prepared esters have high thermal stability. The degradation of the prepared esters takes place in the range between 300 and 600°C. The rheological behaviour of prepared esters shows Newtonian behaviours, which means that Newtonian fluids obey viscosity Newton's law. The viscosity is independent of the shear rate. The results showed that the lubricity properties, based on their pour point, flash point, and oxidation stability of the esters, were significantly affected by the linear and branched alcohols used. There is a slight increase in kinematic viscosity and viscosity index values with decreasing the internal chain length of the dibasic acid. The esters which were based on adipic acid such as C1 exhibited maximum values of VI: 187 compared to those which were based on azelaic acid such as F1 with VI: 182. Viscosity and viscosity index increases with increasing the number of carbon atoms of the used mono‐ol alcohols. Using branched alcohols gave almost the same viscosity results compared to using linear alcohol with the same number of carbons. Almost all prepared esters give pour point results ≤ −30°C. [ABSTRACT FROM AUTHOR]

In the field of mining, one of the exploitation methods that is still the most used in rock salt, potassium, and magnesium salt deposits is the method with the room and abandoned pillar. The salt mining method with rooms and pillars represents a unique spatial system for which the establishment of an optimal correlation between the parameters of the room, pillar, and rock massif is required in any given situation. Thus, the dimensioning of the most requested element in the system is followed, and depending on its parameters, the other parameters of the system are established. Considering the exploitation method with rooms and pillars, the pillars are certainly the elements that are subjected to the greatest loads. In the situation where the deep exploitation of salt is done with square pillars, the evaluation of the optimal parameters of the elements of the exploitation system requires: establishing the loads that appear in the surrounding salt massif (the natural stress state); the qualitative-quantitative determination of the way of distribution of the secondary stress state in the pillars; evaluating the bearing capacity of the pillars; and establishing their geometric elements. Solving this problem can be achieved by different methods: based on the theory of limit equilibrium, taking into account the effective stress in the pillars; methods of the mechanics of the continuous system based on the analytical models for evaluating the secondary stress and deformation state of pillars and floors; and numerical methods combined with the results and measurements from the laboratory and in situ tests. A methodology based on the pillar–room–salt massif interaction principle was proposed for the analytically achievable stability exploitation system of rock salt by the dry method as the depth increased. Applying this method, the secondary stress-deformation state in the pillar can be established by taking into account the rheological behaviour of the salt, changing the pillar shape, and the extraction technology. The presented algorithm can be extended in the field of exploitation, where the room and pillar exploitation methods are used. [ABSTRACT FROM AUTHOR]

The filler-bitumen interaction mechanism is one of the most essential phases for comprehending the asphalt mixture's performance. However, despite numerous studies, in-depth knowledge of filler-bitumen reciprocity at a microscale level is yet to be ascertained. The goal of this research is to gain a better understanding of the filler-bitumen microscale interaction in terms of the synergy and coaction between the physicochemical and rheological performance of mastics due to filler inclusions. The rheological properties of two sustainable mastics, dolomite powder (DP) and lime kiln dust (LKD), together with a neat PEN 60/70 binder, were analysed based on a temperature sweep at elevated temperature conditions. Meanwhile, frequency sweep and multiple stress creep recovery (MSCR) tests were also conducted at pavement serviceability temperature using the dynamic shear rheometer (DSR). Physicochemical tests using a scanning electron microscope (SEM) and energy dispersive X-rays (EDX) were conducted to analyse the impact of parameters such as particle shape, grain size, texture, and chemical compositions. The DSR test results showcased how the incorporation of fillers in asphalt binder considerably improved the performance of the binder in terms of rutting and fatigue. Likewise, its strain and non-recoverable compliance parameters were substantially reduced at higher filler and binder concentrations. Physical filler attributes of low rigden voids (R.V), high fineness modulus (FM), and high specific surface area (SSA) led to greater interfacial stiffness and elasticity in LKD mastics compared to DP mastics at different loading frequencies and temperature levels. The SEM/EDX results also indicated that the elemental calcium and carbon composition of each filler component, together with its grain morphology, strongly influenced its rheological performance.

The lower content of phenolic compounds in white chocolate makes this confectionery product unhealthier and, thus, adequate for enrichment compared to other types of chocolates like dark or milk. Less phenolics in white chocolate is due to absence of dark cocoa solids, abundant in these compounds. This study aimed to develop a new product with a higher nutritional value than regular white chocolate by enriching white chocolate with blueberry juice as a natural source of polyphenols. Since phenolic compounds are highly sensitive to heat, light, oxygen, and pH, encapsulated form of blueberry juice was used to increase their stability in the product. Blueberry juice was encapsulated on maltodextrin (B/M) and added to white chocolate at 80 g/kg and 100 g/kg concentrations. Enrichment significantly (p0.05) except for the sweetness. The enriched chocolate samples were less sweet. The results of this study indicate the potential of maltodextrin as a carrier of sensitive bioactive compounds for the enrichment of products like white chocolate.

The macroscopic rheological properties of suspensions are often inextricably related to changes in their microstructure, and a number of experimental studies have demonstrated the significant influence of DLVO (Derjaguin-Landau-Verwey-Overbeek) interactions, namely microscopic repulsive and attractive forces due to surface charge on particles in suspensions, on the microstructure of suspensions, especially on cluster formation. In this study, the rheological properties of non-Brownian suspensions and their microstructures are investigated by numerical simulations combining DLVO interactions with hydrodynamics and frictional contacts. Different mechanisms have been identified to account for diverse rheological responses of repulsive and adhesive suspensions, revealing a significant association between the evolution of particle clusters and suspension rheology. In repulsive systems, competitions between repulsive and hydrodynamic forces and the resulting change in the distribution of minimum particle separation are responsible for the first shear thinning at low shear rates. Shear thickening is observed at high shear rates and is dominated by particles contacts. Enhancing attractive forces give rise to the viscosity of the suspensions while obscuring shear thickening, and particles make contacts even at the first shear thinning conditions. The second normal stress difference exhibit similar evolution with viscosity while the first normal stress difference is mainly dominated by fluctuations. Microstructure analysis shows frictional clusters appear in repulsive suspensions with growth in both quantity and size as shear rate increases. Clusters in strongly adhesive suspensions, on the other hand, break into smaller ones, resulting in a viscosity reduction. The calculation of the shape anisotropy indicates that frictional clusters in repulsive suspensions tend to expand uniformly in simulation box whereas at high attractive strength, clusters deform more cylindrical when strongly sheared. Our studies in microstructure can fundamentally help in bridging the gap between microscale evolution and macroscale rheological responses, thus contributing to the foundation of the constitutive model of non-Brownian suspensions. [ABSTRACT FROM AUTHOR]

Optimisation design of composite structures requires an accurate predictive model for forming behaviour. The simulation process contains a number of model parameters which include transverse and longitudinal viscosities of continuous fibre-reinforced viscous composites, fundamental to predicting the shear rheology. Shearing the unidirectional composite along the fibre direction gives a measure of the longitudinal viscosity (LV), whilst shearing across or transverse to the fibre direction gives a measure of the transverse viscosity (TV). Numerous experimental work was conducted in the past to measure these two viscosities for various materials. However, conflicting measurements by different test methods were obtained and these apparent discrepancies had not yet been systematically investigated in any single study. This paper reviews previous work on characterisation techniques to further understand the cause of such discrepancy, and hence to improve measurement accuracy, which would benefit future work on theoretical modelling of the composite viscosities and optimisation simulation of composites forming. Some important findings, such as effects of resin-rich areas, contributory factors of elastic effects, non-Newtonian behaviour for composites with Newtonian matrix, aspect ratio and end effects of test samples, geometry effects of fibres and fibre rearrangement during shearing, existence of a mathematical relationship between LV and TV and necessary benchmarking exercise using Newtonian matrix composites, were summarised. [ABSTRACT FROM AUTHOR]

In this paper, the relaxation behavior of polylactic acid (PLA) film in the heat-setting stage of biaxial stretching was studied. Firstly, the polylactic acid casting films were stretched synchronously in different ratios. We found that the Machine direction (MD) and Transverse direction (TD) stress relaxation curves exhibited a separation trend with the increase in the stretching ratio, and the relaxation amplitude increased gradually. Then, the stress relaxation curves were fitted by the expansion exponential equation (KWW equation). The results showed that the coefficient used to characterize the homogeneity of stress relaxation increased with the increase in the stretching ratio, and the homogeneity in Machine direction was better than that in Transverse direction. Finally, we analyzed the evolution of rheological units and the activation energy spectrum during stress relaxation. We found that the volume of rheological units gradually decreased with the increase in the stretching ratio. The activation energy spectrum exhibited a Gaussian distribution, and the symmetry axis of distribution curves shifted to the high energy. The above results would be of great significance in further understanding the deformation mechanism of polylactic acid film during biaxial stretching and providing theoretical guidance for the preparation of high-performance BOPLA films.

In the context of growing interest in plant-based food products for their potential health benefits and sustainability, this study investigates the effect of mono- and diglycerides of fatty acids application on physico-chemical properties of various plant-based cream products, compared to lecithin application in rice cream. Rheological and textural parameters, colour profile, and colloidal stability were analysed. The application of mono- and diglycerides modified the creams’ viscoelastic behaviour, showing a decrease in viscoelasticity across the samples; although in oat–coconut cream resulted in a higher viscoelasticity, indicating the formation of a gel-like structure. Rice cream with lecithin emulsifier showed lower viscoelastic properties characterised by higher phase angle (tan δ). All samples behaved as pseudoplastic materials (with a flow behaviour index n < 1). For coconut and almond creams, the consistency coefficient increased and flow behaviour index decreased after emulsifier application. Interestingly, the emulsifier addition did not significantly affect the cream’s colour profile, characterised by yellow hue angle (h*) as a dominant spectral component. The colloidal stability, indicated by a stability index (SI), was determined as well.

The lotus seed and lily bulb beverage (LLB) has a problem with solid particle sedimentation. To address this issue, LLB was homogenised twice at different pressures (0~100 MPa) using a homogeniser. This study aims to investigate the changes in the particle size distribution (PSD), microstructure, rheological behaviour, sedimentation index (IS), turbidity, physicochemical properties, and sensory quality of LLBs after homogenisation treatments. The results regarding PSD and microstructure showed that the suspended particles were decomposed at high pressure with increasing homogenisation pressure, forming small particles of cellular material, cell wall fragments, fibre fractions, and polymers. The LLB showed shear-thinning behaviour and weak gelation characteristics (G′ > G″) and rheological properties. Among all homogenisation pressures, the 60 MPa sample showed the lowest sedimentation rate and the highest turbidity. When the pressure was increased from 0 to 100 MPa, the total soluble solid (TSS) content showed an upward trend, while the ascorbic acid content (AAC) gradually decreased. The highest sensory evaluation was observed in the 60 MPa sample in terms of overall acceptability.

The use of lignin, an abundant phenolic bio-polymer, allows us to transform our fossil-based economy into a sustainable and bio-based economy. The transformation of bulk lignin into colloidal lignin particles (CLPs) with well-defined surface chemistry and morphology is a possible way to cope with the heterogeneity of lignin and use it for material applications. These CLPs can be used as emulsifiers in so-called Pickering emulsions, where solid particles stabilise the emulsion instead of environmentally harmful synthetic surfactants. This work investigates the application of CLPs produced from various bulk lignins as a stabiliser in o/w Pickering emulsions with two different oil phases (solid and liquid state). The CLPs had a primary particle size of 28 to 55 nm. They were successful in stabilising oil-in-water Pickering emulsions with high resistance to coalescence and a strong gel-like network. This enables novel applications for CLPs in the chemical and cosmetic industries, and can replace fossil-based and synthetic ingredients. [ABSTRACT FROM AUTHOR]

The rheological behaviour of dilute soil-water mixtures, such as hyperconcentrated mixtures and interstitial fluids in debris flows, can significantly affect the flow dynamics of flow-type landslides. These mixtures often contain clay, silt, and sandy particles. Despite great efforts, the effects of soil type and texture on the rheological behaviour of these mixtures are still not well understood. To tackle this issue, an experimental investigation is carried out using a narrow-gap rotational viscometer to evaluate the interactions from colloidal (clay) and non-colloidal (silt and sand) particles and possibility of flow regime change. The flow curves of dilute mixtures are determined with and without a dispersion agent. A functional curve between spindle speed and Reynolds Number or Froud Number is proposed to distinguish different flow regimes in the narrow-gap rotational viscometer. Results demonstrate the applicability of the Bingham model for describing the bulk rheological behaviour of dilute mixtures. The mixture viscosity governs the contribution of the hydrodynamic effects from all particles, while the yield stress governs the contribution of the colloidal effects from colloidal particles. Results also reveal that for dilute mixtures containing particles up to medium sand size, the main cause of the flow regime change is the flow boundary conditions. [ABSTRACT FROM AUTHOR]

Summary: The study aimed to evaluate the potential ingredient of stigma maydis (S.M.) as a hypoglycaemic functional food. In the present study, waxy corn flour and corn‐resistant starch were used to make biscuits; the influence of S.M. extracts (aqueous extract, SMA; ethanol extract, SME; mixed solvent extract, SMM) on the physical features and in vitro digestibility of biscuit were surveyed. In the meantime, the α‐amylase and α‐glucosidase inhibition of different S.M. extracts were analysed. Compared with the control dough, 5% ethanol S.M. extract (SME2) dough was observed to have the lowest storage modulus (G'), loss modulus (G"), hardness, water absorption capacity (P < 0.05), while creep strain was the highest (P < 0.05). Adding S.M. extracts could significantly reduce the L*, b* value and increase the a* value of biscuits. Besides, the S.M. extracts could decrease the glycaemic index (G.I.) of biscuits and reduce postprandial blood glucose levels. The GI of SMA1, SMA2, SME1, SME2, SMM1 and SMM2 was decreased to 62.47, 55.17, 51.46, 44.89, 53.05 and 50.11 respectively. Further, the addition of S.M. extract could show a certain inhibitory rate of α‐amylase and α‐glucosidase when added to biscuits. The inhibition ratio of 5% extract (SMA2, SME2 and SMM2) biscuit was higher than that of 1% extract (SMA1, SME1 and SMM1) biscuit (P < 0.05). As a natural functional component, S.M. extract could be a potential food supplement for type II diabetic mellitus. [ABSTRACT FROM AUTHOR]

The existence of a reducing end in the structure of maltodextrin can limit its applications as undesirable Maillard reaction would occur in some food processing steps. Consequently, a non-reducing maltoheptaose (N-G7) with a single degree of polymerisation was prepared through a cascade reaction of cyclodextrinase and maltooligosyltrehalose synthase, using β-cyclodextrin as substrate. The physicochemical properties of N-G7 were investigated. N-G7 exhibited low moisture absorption ability (8.91 and 18.02% at 43 and 81% relative humidity, respectively), excellent pH stability and thermostability (less than 10% N-G7 was hydrolysed between pH 4 and 10, even at 100°C), and a melting point higher than that of maltodextrin, as well as a typical gel-like behaviour. Most importantly, the results of Maillard reaction indicated that N-G7 was considered to be non-reducing, which suggested that it could be used in food processing where Maillard reaction should be avoided. Overall, the present work may provide important implications for the development and application of N-G7 in food products. [ABSTRACT FROM AUTHOR]

Water soluble coconut extract (WSCE) was reported as a suitable matrix for probiotic delivery as yogurt alternatives. The study aimed to evaluate the roles of brewers’ spent grain (BSG) derivatives in enhancing the properties of WSCE-based yogurt alternatives. BSG flour (BSGF) and 3 different protein extracts (BSGPs) including protein control (BSGP-C), protamex treatment (BSGP-P), and protamex combined with flavourzyme treatment (BSGP-PF) were incorporated in WSCE-based yogurt alternatives. Confocal laser scanning microscopy showed that BSGPs prepared with protease treatment generated less dense fat distribution and more homogenous globules compared to that in WSCE control yogurt. It also resulted in a softer, denser and more homogenous matrix. The modification in microstructural properties was aligned with differences in several functional groups including ⍺-glycosidic bond and hydroxyl groups from polysaccharides, aliphatic ethers and acid functional groups as well as aromatic hydrocarbons of lignin, amide I, acetyl groups and amide III. BSGF and BSGPs increased the mechanical properties, viscosity and modified flow behaviour properties demonstrating its ability in maintaining textural and gel formation. After 14 days of storage, maintenance in flow behaviour, syneresis and mechanical properties was identified. Furthermore, BSG derivatives enhanced lactic acid production up to 3 folds. In conclusion, BSG derivatives maintained the microstructure and gel formation, improved the properties of WSCE-based yogurt alternatives and preserved its behaviour during 14 days of storage.

Despite the emerging interest of biochar utilization in cement-based construction materials, there is insufficient understanding on the fresh-state performance of biochar-cement composites. In this study, various biochar samples with different characteristics were prepared as bio-based admixtures to adjust the rheo-viscoelastic properties of cement pastes, and the rheological parameters and viscoelastic evolution of the cement mixtures were comprehensively investigated. The results indicated that the type of biomass waste as biochar feedstock should be considered as the primary factor affecting its efficacy in rheological modification, owing to the distinct morphologies and water absorption capacities of biochar particles. The rheological behaviour was also tailored by different functional groups, chemical compositions, hydrophobicity, and carbon structure of the biochar. The use of 2% food waste biochar (FWBC, pyrolyzed at 500 °C) decreased the static and dynamic yield stress by 22% and 37%, enhanced the plastic viscosity by 13% and the thixotropy by 4%, and retarded the percolation by 57% and the rigidification by 31%. In contrast, the use of 2% agriculture waste biochar (AWBC, pyrolyzed at 800 °C) enhanced the static and dynamic yield stress by 252% and 187%, increased the plastic viscosity by 129% yet reduced the thixotropy by 13%, and accelerated the percolation by 124% and the rigidification by 45%. These results illustrated the important roles of different biochar in adjusting the fresh-sate performance of cementitious mixture. This study can provide theoretical support for producing self-compacting concrete and/or printable concrete with adaptive rheological behaviour towards low-carbon construction. [Display omitted] • Viscoelastic behaviour of fresh biochar-cement composites was the first time reported. • Engineered biochar was customized with desired intrinsic textural characteristics. • Biochar as bio-based admixture effectively adjusted adaptive fresh-state performance. • Food waste biochar led to a lower dynamic yield stress with a higher plastic viscosity. • Agriculture waste biochar let to a higher static yield stress with accelerated structural build-up. [ABSTRACT FROM AUTHOR]

Fibrous membranes based on natural polymers obtained by the electrospinning technique are a great choice for wound dressings. In order to promote an efficient wound repair, and to avoid antibiotics, antibacterial plant extracts can be incorporated. In the present work, the new electrospun nanofibre membranes based on monobasic phosphate curdlan (PCurd) and polyvinyl alcohol (PVA) were obtained for the first time. To establish the adequate mixing ratio for electrospinning, the behaviour of the PCurd and PVA mixture was studied by viscometry and rheology. In order to confer antimicrobial activity with the nanofibre membrane, clove essential oil (CEO) was incorporated into the electrospun solution. Well-defined and drop-free nanofibres with a diameter between 157 nm and 110 nm were obtained. The presence of CEO in the obtained nanofibres was confirmed by ATR–FTIR spectroscopy, by the phenolic and flavonoid contents, and by the antioxidant activity of the membranes. In physiological conditions, CEO was released from the membrane after 24 h. The in vivo antimicrobial tests showed a good inhibitory activity against E. coli and higher activity against S. aureus. Furthermore, the viability cell test showed the lack of cytotoxicity of the nanofibre membrane with and without CEO, confirming its potential use in wound treatment. [ABSTRACT FROM AUTHOR]

Effect of adding foxtail millet flour (FMF) (10, 20, and 30% w/w) to refined wheat flour (RWF) on physicochemical and rheological properties of dough was studied. Qualitative properties of Brotchen bread including moisture, ash, crude fibre, specific volume, and colour of the breads were evaluated. Adding FMF to the flour increased crude fibre, fat, ash, and protein contents and reduced falling number, damaged starch and wet gluten contents, and sample lightness. Consistograph test indicated that addition of the FMF decreased water absorption capacity, maximum pressure, and tolerance, however, drops in pressure at 250 and 450 s became greater. Alveograph test revealed that with adding FMF, dough resistance to extension and dough strength decreased but an increase in dough extensibility was obtained at FMF30%. Increasing the amount of FMF resulted in a decrease in the volume of the bread, and the FMB (foxtail millet bread) 30% had the highest browning index and b*. The FMB20% had the highest resilience and springiness, while higher level of foxtail (30%) increased chewiness. [ABSTRACT FROM AUTHOR]

The evolution of sustainable binders for various construction applications has resulted in the development of various geopolymer binders using various materials as aluminosilicate precursors. Geopolymer binders can be utilized as an alternative to Portland cement in the production of various materials such as mortar and concrete. In this study, geopolymer binders were synthesized using metakaolin (MK) and meta-halloysite (MH) as the aluminosilicate precursors and activated with an alkali solution having a silica modulus of 1.3 and 1.5. The resulting geopolymer binders were assessed in terms of the mechanical, permeability and durability properties. The findings from this study showed that the use of MH as the precursor resulted in better performance compared to when MK was used due to its higher reactivity and fineness. It was also found out that the use of a silica modulus of 1.5 is favourable to the hardened properties of the geopolymer binders. Geopolymer binders synthesized with MH and an activator with a silica modulus of 1.5 exhibited an increase in compressive and flexural strength of approximately 9 MPa and 1 MPa, respectively compared to when a silica modulus of 1.3 was used. Also, the corresponding porosity and water absorption is 14.5% and 10.9%, respectively lower.

The aim of this study was to evaluate the impact of high-pressure processing (HPP) on the long-term storage of chocolate fillings at room temperature, compared with conventional storage at lower temperatures. Dark chocolate fillings were treated at different pressure levels, holding times and stored at 20 °C for 12 months. Unprocessed batches were stored at 4 °C and at −12 °C. Moisture, water activity (aw), pH, colour, G′1Hz and indigenous microflora were measured at 2, 4, 6, 8, 10 and 12 months of storage. Results showed that 600 MPa/20 min processing was the most effective controlling mesophilic group, presenting 3.8 log cfu/g after 12 months of storage, and inactivating moulds and yeasts after HPP treatment. Colour was affected by storage, including a reduction in the L* parameter in all conditions to final values between 37.8 and 39.3, while the a* parameter increased during storage time at −12 °C and 4 °C to final values of around 12, and parameter b* decreased at storage temperature 20 °C to 5.3. Storage time affected the rheological behaviour of HPP-treated samples, increasing G′1Hz from the 2nd to 12th month of storage time to the final values between 1603 kPa and 2139 kPa. Moisture, aw and pH were not affected by HPP treatment nor storage time. [ABSTRACT FROM AUTHOR]

The present study aimed to develop lomefloxacin-loaded ethosomal vesicles intended to be applied topically for treating skin infections. Ethosomes were prepared using the cold method. The formulation variables were optimized using 22 factorial design and Design Expert® software for analyzing the data statistically and graphically using response surface plots. Phosphatidylcholine (X1) and ethanol (X2) were chosen as the independent variables, while the dependent variables comprised entrapment efficiency (Y1), vesicles size (Y2) and zeta potential (Y3). The optimized ethosomes were subsequently incorporated into Carbopol® 940 gel and characterized for rheological behaviour, in-vitro release, ex-vivo skin permeation and deposition. The ex-vivo permeation and skin deposition studies showed better results compared to drug solutions. In a nutshell, the ethosomal vesicles were found to be a promising carrier demonstrating enhanced topical delivery of lomefloxacin. [ABSTRACT FROM AUTHOR]

Fibrous membranes based on natural polymers obtained by the electrospinning technique are a great choice for wound dressings. In order to promote an efficient wound repair, and to avoid antibiotics, antibacterial plant extracts can be incorporated. In the present work, the new electrospun nanofibre membranes based on monobasic phosphate curdlan (PCurd) and polyvinyl alcohol (PVA) were obtained for the first time. To establish the adequate mixing ratio for electrospinning, the behaviour of the PCurd and PVA mixture was studied by viscometry and rheology. In order to confer antimicrobial activity with the nanofibre membrane, clove essential oil (CEO) was incorporated into the electrospun solution. Well-defined and drop-free nanofibres with a diameter between 157 nm and 110 nm were obtained. The presence of CEO in the obtained nanofibres was confirmed by ATR–FTIR spectroscopy, by the phenolic and flavonoid contents, and by the antioxidant activity of the membranes. In physiological conditions, CEO was released from the membrane after 24 h. The in vivo antimicrobial tests showed a good inhibitory activity against E. coli and higher activity against S. aureus. Furthermore, the viability cell test showed the lack of cytotoxicity of the nanofibre membrane with and without CEO, confirming its potential use in wound treatment.

The aim of this study was to evaluate the impact of high-pressure processing (HPP) on the long-term storage of chocolate fillings at room temperature, compared with conventional storage at lower temperatures. Dark chocolate fillings were treated at different pressure levels, holding times and stored at 20 °C for 12 months. Unprocessed batches were stored at 4 °C and at −12 °C. Moisture, water activity (aw), pH, colour, G′1Hz and indigenous microflora were measured at 2, 4, 6, 8, 10 and 12 months of storage. Results showed that 600 MPa/20 min processing was the most effective controlling mesophilic group, presenting 3.8 log cfu/g after 12 months of storage, and inactivating moulds and yeasts after HPP treatment. Colour was affected by storage, including a reduction in the L* parameter in all conditions to final values between 37.8 and 39.3, while the a* parameter increased during storage time at −12 °C and 4 °C to final values of around 12, and parameter b* decreased at storage temperature 20 °C to 5.3. Storage time affected the rheological behaviour of HPP-treated samples, increasing G′1Hz from the 2nd to 12th month of storage time to the final values between 1603 kPa and 2139 kPa. Moisture, aw and pH were not affected by HPP treatment nor storage time.

• A novel polymer drag reducer with good temperature resistance was synthesized. • The rheological properties of temperature resistant polymer solutions were evaluated comprehensively. • Under high temperature conditions, the drag reduction performance of slickwater is excellent. The drag reduction rate at 110 °C is 72.57 %, which remains 96.68 % compared with that at 25 °C. • The drag reduction behaviors of temperature resistant slickwater under different conditions, including various displacements, concentrations, temperatures, pipe diameters, salinities, were evaluated. • The drag reduction mechanism was clarified by AFM microscopic characterization. Slickwater has been extensively utilised in deep reservoir fracturing owing to its excellent drag reduction performance, and the polymer drag reducer is the core of slickwater. However, polymer drag reducers may degrade at high temperatures, which limits the application of slickwater in high temperature reservoirs. To increase the temperature resistance of slickwater, a novel temperature-resistant polymer drag reducer was chemically synthesised through free-radical polymerisation using acrylamide (AM), acrylic acid (AA), 2-acrylamide-2-methylpropyl sulfonic acid (AMPS) and N,N-dimethylacrylamide (DMAA). The introduction of temperature-resistant monomers substantially increased the thermal stability of the drag reducer. The rheological measurements revealed that the aqueous polymer solution was a pseudoplastic fluid with good viscoelasticity and thickening properties. At 110 °C, the drag reduction rate of 0.03 wt% polymer aqueous solution could reach 72.57 %, and the drag reduction retention rate was 96.69 % when compared with that at 25 °C. The drag reduction performance was evaluated in relation to displacement, concentration, temperature, pipe diameter, and salinity. Simultaneously, the proportion of factors influencing the drag reduction performance was analysed. Finally, a drag reduction mechanism was proposed. This study is expected to extend the application of slickwater in high-temperature reservoir development. [ABSTRACT FROM AUTHOR]

[Display omitted] • New chiral liquid crystalline materials based on lactic acid with hydroquinone unit are designed. • Materials possess a very broad temperature range of the cholesteric phase. • In the cholesteric phase electric field applied perpendicular to the flow resulted in an increase in viscosity. • Liquid crystalline behaviour is discussed and compared to structurally similar chiral self-assembling materials. In order to contribute to molecular structure – physical property relationship for chiral self-assembling materials, two chiral compounds derived from the lactic acid have been designed. Mesogenic core of materials consists of two benzoate units and one hydroquinone unit connected by the ester linkage groups and two flexible alkyl chains. Different lengths of the chiral alkyl chain were tested, while the length of the achiral alkyl was kept same for all materials. The mesomorphic properties were established by polarizing optical microscopy and differential scanning calorimetry. Both materials possess reasonably broad and stable cholesteric (N*) phase down to room temperature. The rheological characterisation was performed in the N* phase on the compound with shorter chiral alkyl chain using a rotational rheometer in a plate/plate geometry with and without external electric field applied perpendicularly to the flow direction. The results reveal a shear thinning behaviour, even without electric field applied. The N* phase exhibits a slight electrorheological effect, at low shear rates, that continuously decrease with the increase of the shear rate, due to the competition of the flow and electric fields. The mesomorphic behaviour of the designed materials was compared to structurally similar materials. Quite broad temperature range of the N* phase down to room temperature makes studied lactic acid derivatives as suitable chiral dopants for design of new multicomponent mixtures targeted for various applications in photonics and optoelectronics. [ABSTRACT FROM AUTHOR]

Red seaweeds are exploited for their hydrocolloids, but other fractions are usually overlooked. In a novel approach, this study aimed to evaluate cold-water (CWE), ethanolic (EE), and alkaline (SE) extractions, alone and in sequence, to simultaneously: i) decrease the hydrocolloid extraction waste (valorizing bioactive side-streams and/or increasing extraction yield); and ii) increase the hydrocolloids' texturizing properties. It is the first time these extractions' synergetic and/or antagonistic effects will be accessed. For Porphyra dioica , a combination of CWE and EE was optimal: a positive influence on the melting temperature (increasing 5 °C to 74 °C) and sulphate content (a 3-fold reduction to 5 %) was observed, compared to a direct porphyran extraction. The same was observed for Gracilaria vermiculophyla , recovering two additional bioactive fractions without impacting the hydrocolloid's extraction (agar with 220 g/cm2 gelling strength and 14 % yield was obtained). The sequential use of CWE, EE, and SE was the most beneficial in Gelidium corneum processing: it enhanced agar's texturizing capacity (reaching 1150 g/cm2, a 1.5-fold increase when compared to a direct extraction), without affecting its 22 % yield or over 88 % purity. Ultimately, these findings clarified the effects of cascading biorefinery approaches from red seaweeds and their pertinence. [ABSTRACT FROM AUTHOR]

Researchers, engineers, scientists, and other professionals have been focusing on the exploitation of nanotechnology with specific attention to nanofluids and their property of dynamic viscosity that can do wonders in the field of engineering. This study was aimed at determining the dynamic viscosity of the given hybrid nanofluid (distilled water based ZrO 2 /SiC) by studying the nanofluid's rheology. In this regard, a two-step method was employed for the dispersal of nanoparticles in the base fluid. The nano-powder was composed of ZrO 2 and SiC in a ratio of 1:1 (50% - 50%). The dynamic viscosity of solid volume fractions 0.025% - 0.1% was measured in temperatures 20–60 °C by using DV2TRVTBG Brookfield digital viscometer. The research indicated the association between the nanofluid's viscosity and the factors of temperature and solid volume fraction. At first, in order to assessment the characteristics and stability of nanoparticles into the base fluid, XRD, TEM, FESEM, EDX, UV–vis spectrometer, DLS, and zeta potential test were used on ZrO 2 and SiC nanoparticles. The results indicated an increase in dynamic viscosity at higher solid concentrations and falling temperatures. The dynamic viscosity increase of the nanofluid was recorded at 20 and 60 °C, which showed a 29.6% and 64.2% rise in the viscosity respectively in the presence of 0.025% of nanoparticles in the nanofluid. This implies that the viscosity of nanoparticles becomes more sensitive at high temperatures. The experiment showed a maximum viscosity rise of 169.4%. The experiments also discovered that ZrO 2 -SiC /DW hybrid nanofluid can be successfully used in different devices as a Newtonian fluid since it depicts Newtonian properties at various temperatures. In addition, the study put forward a new correlation for determining the dynamic viscosity of hybrid nanofluid using the experimental data (temperature and solid volume fraction). The value of mathematical correlation accuracy was 98.92%. During the experiment, the sensitivity of viscosity in response to a rise in solid volume fraction was evaluated. Lastly, an acceptable level of accuracy of the correlation outputs was seen when the theoretical and practical values were contrasted. [Display omitted] • Experimental study on dynamic viscosity of ZrO 2 -SiC/DW hybrid nanofluid. • The Newtonian behaviour of nanofluid was observed at each temperature setting. • An increase in the solid volume fraction causes the viscosity to rise. • The study put forward a new correlation for predicting the nanofluids viscosity. • The sensitivity analysis of the viscosity of hybrid nanofluid is also performed. [ABSTRACT FROM AUTHOR]

This study investigated the effects of the combined application of transglutaminase (TG) and κ -carrageenan (KC) on the rheological behaviours, gel properties, and microstructures of meat batters before and after heat treatment. The results indicated that the combined addition of TG and KC could significantly improve the apparent viscosity and viscoelastic behaviour of uncooked meat batter, and lead to a more rigid network structure and faster elastic response than the addition of either TG or KC. Moreover, apart from the formation of a denser and finer gel network, the gel properties of cooked meat batter were effectively improved after the addition of TG and KC. Compared with the samples containing either TG or KC, cooked meat batter containing 0.3% TG and 0.2% KC exhibited the highest hardness, adhesiveness, chewiness, and springiness (P < 0.05), this was verified by the rheological test under the temperature sweep mode. Therefore, compared with the addition of TG or KC alone, the combined addition of TG and KC could synergistically enhance the gel properties and viscoelastic behaviour of meat batter. [Display omitted] • Transglutaminase (TG) and κ -carrageenan (KC) were combined added to meat batter. • TG and KC synergistically affected the rheological behaviours of meat batter. • The gel properties of meat batter containing KC were greatly enhanced by TG. • Excessive covalent cross-links disrupted interaction between KC and proteins. [ABSTRACT FROM AUTHOR]

• Thermophysical, rheological and dielectric profiles are analysed for carbon black nanofluids based on polyethylene glycol. • Designed nanofluids are stable by using PVP surfactant for 28 days. • CB dispersed nanoparticles entail latent heats of fusion up to four times superior to that of PEG200. • Newtonian behaviour was reported for all samples excepting the highest loaded proposed nanofluid. • The electrical permittivity of the proposed nanofluids is increased in the independent frequency region. Phase change materials can store or release large amounts of energy during phase change. An increasing number of authors are studying the influence of the dispersion of nanometric particles on these materials. This article presents the design and experimental characterization of temporal stability, thermal conductivity, isobaric heat capacity, phase change transitions, rheological behaviour, and dielectric properties of nano-enhanced phase change materials based on carbon black (CB) dispersions in polyethylene glycol (PEG200) by using polyvinylpyrrolidone (PVP) as surfactant. We studied the temporal stability of carbon black nanoparticles dispersed in PEG200 using dynamic light scattering and spectrophotometry techniques. All the samples showed good temporal stability, since the measurements of the hydrodynamic size of the nanoparticles are practically constant over time and the wavelength observed by UV–vis shows a small variation of around 4% for static conditions. We observed small changes in thermal conductivity and isobaric heat capacity. Nevertheless, the thermograms evidence how the latent heat clearly increases with the load of carbon black nanoparticles up to four times that of the PEG200. The viscosity studies do not show variation with shear rate, indicating a Newtonian behaviour, excluding the 2.0 wt% CB/PVP + PEG200 nanofluid. Additionally, we noticed frequency dependent and independent regions for permittivity. [ABSTRACT FROM AUTHOR]

• The first-order solid–liquid transition of PT8 is not significantly altered by the dispersion of different nanomaterials. • Reductions in sub-cooling for GnP/PT8 NePCMs are higher than for MgO/PT8 ones. • Thermal diffusivity enhancements are higher for GnP/PT8 than for MgO/PT8. • MgO/PT8 nanofluids are viscoplastic (solid at rest), while GnP/PT8 are viscoelastic (liquid at rest). • The fractal structure of MgO forms a strong gel network; the sheet-like shape of GnP favour liquid-like behaviour. A comprehensive study has been performed on the thermal and rheological behaviour of two sets of isooctyl stearate (PureTemp 8, PT8) based nanofluids with different concentrations of spherical MgO nanoparticles (up to 15 wt%) and graphene nanoplatelets (up to 2 wt%). The results show that the presence of the nanomaterials does not significantly alter the phase change temperatures of the base fluids, although the latent heat decreases by 27% and 7.6% for 15 wt% MgO and 1.0 wt% GnP-based nanofluids, respectively. Both nanomaterials are found to increase the thermal diffusivity of the nanofluids. GnP-based suspensions have a higher thermal diffusivity than the MgO ones at similar nanomaterial concentrations. Rheological analyses show that MgO-PT8 nanofluids behave as a viscoplastic material (solid at zero shear rate); whereas the GnP-PT8 samples are viscoelastic (liquid at zero shear rate). MgO nanoparticles promote the formation of large fractal agglomerates, leading to a strong gel network of particles within PT8, while platelet-shaped GnP gives a fluid-like behaviour. [ABSTRACT FROM AUTHOR]

[Display omitted] • A stable AC-ZSM5 ink with appropriate rheological properties was prepared. • The net-like morphology realized by DIW enhances the mass transfer flux. • The submicron-micron pores induced by NH 3 and CO 2 accelerate VOC inward diffusion. • In-situ heating could effectively recover the performance of the adsorption film. In-situ thermally restorable adsorption films exhibited brilliant performance for indoor volatile organic compounds (VOCs) purification with negligible wind resistance and considerable lifetime. However, the morphology of adsorption films should be restructured for better adsorption kinetics. This study structured adsorption films with submillimeter-sized channels by direct ink writing (DIW). Submicron-micron-sized porous structure was further fabricated through ammonia carbonate treatment. Pore size distribution characterization proved 33% of extra mesopores were created in the hierarchical porous adsorption film. Dynamic adsorption behaviours for formaldehyde and toluene illustrated that the hierarchical porous adsorption film exhibited an over 80% initial one-pass efficiency for both formaldehyde and toluene, improved by 20% over the plane adsorption film. The purification rate was also significantly improved by 83% and 67% for formaldehyde (from 0.059 mg g-1h−1 to 0.106 mg g-1h−1) and toluene (from 0.143 mg g-1h−1 to 0.239 mg g-1h−1), respectively. This study proposed a method for conveniently preparing multi-scale porous structured adsorption components under mild conditions. The hierarchical diffusion pathways induced by DIW and ammonium carbonate treatment will enhance the adsorption kinetics and the purification performance of the adsorption film, overcoming the weak purification performance and short material lifetime of the existing indoor VOCs adsorption components. This research can be further applied to gas separation, as well as gas sensing, as DIW can achieve sub-millimeter scale resolution, providing a versatile approach for heat and mass transfer enhancement in chemical and environmental fields. [ABSTRACT FROM AUTHOR]