Search Results (12,039)

For effectively assessing blood, red blood cell (RBC) aggregation and blood viscosity have been measured in microfluidic environments. However, the previous methods still face several challenges (dead-volume loss, RBC sedimentation, hematocrit-sensitive blood velocity, and precise flow rate control). In this study, a novel method is suggested to resolve several issues. Air cavity (V_air = 250 μL) is secured above the blood column (at least 100 μL) loaded into a driving syringe. To probe RBC aggregation and blood viscosity, a microfluidic chip consists of a main channel ($\dot{\gamma }$ > 1000 s⁻¹) and an aggregation channel ($\dot{\gamma }$ < 50 s⁻¹). Blood is supplied into a microfluidic chip with two-step blood delivery (i.e., air compression for RBC aggregation, and syringe pump for blood viscosity). RBC aggregation index and blood viscosity are obtained from time-lapse image intensity and blood flow rate in both channels. As performance demonstrations, first, the measurement accuracy of fluid viscosity is validated with glycerin solution. Then, the present method is adopted to probe the difference in hematocrit and dextran concentration. At last, the proposed method is employed to detect heat-shocked RBCs (45~50 °C for 40 min). In conclusion, the proposed method has the ability to accurately measure substantial changes in RBCs or blood medium. Full article

In conventional low-viscosity solvents, magnetic field effects (MFEs) in photoredox catalysis are often negligible because photogenerated radical ion pairs (RIPs) diffuse apart before significant spin evolution occurs. This study reports using ionic liquids (ILs) as a tunable homogeneous “solvent cage” to observe distinct low-field MFEs in the phenothiazine-mediated photoinduced reductive dechlorination of aryl chlorides. Experimental results demonstrate that MFEs increase significantly with bulk viscosity, reaching saturation at approximately 1000 Gs with a maximum enhancement of about 15%, consistent with the hyperfine coupling mechanism (HFCM). Femtosecond transient absorption spectroscopy (fs-TA) reveals that the ionic liquid environment effectively reduces the radical cage escape rate, matching it with the spin evolution rate. This allows the external magnetic field to intervene in the back electron transfer (BET) process. However, unlike strongly confined micellar systems, the contribution of the triplet charge recombination (TCR) pathway here is moderate, intrinsically limiting the magnetic enhancement amplitude. These findings establish that MFE magnitude is determined by both viscosity-controlled cage dynamics and the efficiency of the TCR channel, providing a mechanistic basis for designing spin-modulated homogeneous photoredox systems. Full article

This study aimed to develop a solvent removal-based in situ forming gel (ISG) loaded with salicylic acid (SAL) using myristic acid (MYR) as a matrix-forming agent. SAL-loaded MYR-based ISGs were prepared using N-methyl-2-pyrrolidone (NMP) or dimethyl sulfoxide (DMSO) as solvents and evaluated for physicochemical properties, matrix formation behavior, mechanical characteristics, and in vitro drug release. Increasing MYR content influenced viscosity, gel formation kinetics, and depot integrity, resulting in prolonged SAL release of up to 20 days in DMSO-based formulations. The release kinetics were best described by the Peppas–Sahlin model, indicating diffusion-dominated drug transport. The selected formulation containing 30% w/w SAL and 20% w/w MYR exhibited acceptable injectability, reproducible in situ matrix formation, and sustained drug retention. Antimicrobial testing confirmed that SAL retained biological activity against oral pathogens following incorporation into the ISG system, although solvent contributions to antimicrobial effects were also observed. These findings demonstrate the feasibility of a MYR-based ISG system in which SAL contributes to both therapeutic activity and matrix formation, supporting its potential for localized oral drug delivery. Full article

Deep-sea gear transmission systems encounter critical lubrication challenges arising from the synergistic coupling of extreme hydrostatic pressure and cryogenic temperatures. These environmental stressors induce exponential viscosity escalation in lubricants, precipitating severe fluidity degradation, elevated startup resistance, and lubrication starvation. Concurrently, seawater intrusion triggers lubricant emulsification, additive deactivation, and electrochemical corrosion at meshing interfaces, collectively escalating the risk of catastrophic lubrication failure and compromising long-term operational reliability. This study systematically elucidates the lubrication degradation mechanisms inherent to deep-sea environments and proposes targeted mitigation strategies. Through comprehensive characterization of deep-sea environmental parameters and their impact on lubricant rheological behavior, we critically evaluate the applicability and inherent limitations of conventional Thermal Elasto-Hydrodynamic Lubrication (TEHL) theory under extreme conditions. Our analysis reveals that established TEHL frameworks necessitate substantial modification to accurately capture pressure-viscosity-temperature coupling phenomena and seawater contamination kinetics. Meshing interface texturing, as an effective anti-friction and wear-mitigation strategy, is investigated to delineate its mechanistic pathways for enhancing lubricant film formation and tribological performance under starved lubrication regimes. Key findings demonstrate that optimized micro-texture architectures can effectively compensate for viscosity-induced fluidity deficits and attenuate the deleterious effects of seawater ingress. Critical knowledge gaps are identified, and future research trajectories are charted: (i) multiphysics coupling models integrating thermo-hydrodynamic, chemo-physical, and mechanical degradation processes; (ii) synergistic texture-coating design paradigms; (iii) high-pressure low-temperature experimental validation protocols; and (iv) engineering implementation frameworks for deep-sea gear transmission systems. This review establishes theoretical foundations and provides technical guidelines for robust lubrication design and long-term operational stability of deep-sea transmission equipment. Full article

This study investigated the effects of bovine colostrum and whey protein concentrate (WPC) on the physicochemical, functional, microbiological, and sensory properties of fermented milk beverages formulated with different ingredient compositions and starter culture variants. Four formulations were evaluated during two weeks of refrigerated storage. WPC addition markedly reduced viscosity, with the lowest value observed in WPC enhanced samples (0.26 Pa·s), whereas skimmed milk powder contributed to a more balanced texture. Syneresis was highest in the WPC-rich formulation (6.9 mL) and lower in colostrum-containing samples (3.2–4.9 mL), indicating improved water-holding capacity. Colostrum enhanced antioxidant activity, with ABTS values reaching approximately 240–250 µM Trolox/mL during mid-storage, followed by a decline on day 14. Sensory evaluation showed the highest consumer acceptance for samples containing balanced proportions of colostrum and WPC, while formulations with high WPC content scored lower due to inferior texture and appearance. The applied formulations also supported the viability of Bifidobacterium spp. during refrigerated storage, maintaining counts at levels considered adequate for probiotic dairy products. Overall, the combined use of bovine colostrum and WPC resulted in fermented milk beverages with improved functional properties, structural stability, probiotic viability, and sensory acceptability. Full article

(1) Background: Starch-based breads can closely mimic wheat bread in texture and appearance; however, their nutritional value must be improved while maintaining their inherent bread-like characteristics. The objective of this study was to incorporate whole-grain pearl millet flour (PMF) into a starch-based bread formulation to enhance its dietary fiber and protein content. (2) Methods: The PMF was obtained using a combination of laboratory rollers and hammer mills, as well as appropriate sieves to obtain a particle size ≤ 250 µm. The incorporation of PMF affected the properties of the base flour (BF), dough, and gluten-free bread (GFB). (3) Results: In the BF, setback viscosity was significantly reduced from 6379 to 1354 mPa·s. Similarly, in the freshly kneaded dough, both the elastic and viscous moduli decreased, from 168.3 to 17.8 kPa and from 36.3 to 4.3 kPa, respectively. During fermentation, dough-specific volume increased from 0.76 to 1.73 cm³/g. In the GFB, the moisture content decreased from 47.9 to 42.2%, bread specific volume varied from 2.13 to 2.68 cm³/g, and crumb hardness increased from 12.8 to 25.3 N. PMF incorporation segmented bread consumers into two preference-based clusters, characterized by lower (1) and higher (2) PMF levels. (4) Conclusions: Incorporating 30% PMF increased the fiber and protein contents of the starch-based bread by 4.9% and 2.2%, respectively, without compromising specific volume (2.56 g/cm³) or overall acceptance, which remained comparable to that of a commercial gluten-free bread (7.30 and 6.32 for clusters (1) and (2), respectively). Full article

A composite meeting the UL94 V-0 rating was produced by adding 30 wt% epoxy silane-modified aluminum trihydrate (EPATH) to a 60/40 epoxy/benzoxazine matrix. Various bimodal and trimodal composites containing 20–40 wt% of three types of ceramic fillers, i.e., aluminum oxide (Al₂O₃), boron nitride (BN), and magnesium oxide (MgO), were prepared to simultaneously achieve flame-retardant and thermal conductive properties. The bimodal composites with 40 wt% of Al₂O₃ and MgO exhibited thermal conductivities of 1.22 W/m∙K and 1.29 W/m∙K, respectively, which were superior to that of the composite containing the same amount of ATH (1.0 W/m∙K). In contrast, both the coefficient of thermal expansion (CTE) and shear strength decreased with increasing ceramic filler content. For agglomerated BN, the filler loading was constrained above 30 wt% because its high specific volume caused a significant rise in the viscosity. In the trimodal composites with a total filler content of 40 wt% of Al₂O₃ and BN, a BN fraction of 7.5 wt% yielded the highest thermal conductivity of 1.64 W/m∙K and the lowest water absorption of 0.69%. When the trimodal composites were exposed to −55 °C and 150 °C for 1000 h, they exhibited a reduction in shear strength of less than 30% compared to their initial values. Full article

Deep eutectic solvents (DESs) have emerged as promising green alternatives to conventional organic solvents for the extraction of bioactive compounds from natural matrices because of their tunable physicochemical properties, low toxicity, and environmental compatibility. However, most existing reviews primarily focus on application-based results, with limited mechanistic and process engineering interpretations necessary for industrial applications. This review provides a comprehensive analysis of DES-based extraction from the perspective of separation and process engineering, emphasizing the relationships between DES composition, physicochemical properties, mass-transfer behavior, and extraction performance. Key parameters, including viscosity, hydrogen bonding interactions, solvent-to-feed ratio, temperature, and water content, are critically evaluated in terms of their influence on extraction efficiency, selectivity, and scalability. Furthermore, solvent recovery, process intensification strategies, and industrial implementation challenges are discussed to bridge the gap between laboratory research and large-scale application. By integrating mechanistic insights with process-level considerations, this review provides a systematic framework for the rational design and optimization of DES-based extraction processes as sustainable and scalable-separation technologies. Full article

Scale-up synthesis in doped semiconductor metal oxide plasmonic nanocrystal batch reaction dispersion mixture processes often leads to significant changes in rheological behavior and flow characteristics, especially when using high-viscosity organic media. In this study, the rheological and hydrodynamic properties during the scale-up of a nanocrystal dispersion system where oleyl alcohol was used as a reaction solution medium were investigated. The flow field in a mechanically stirred 4 L pilot reactor was numerically analyzed using ANSYS Fluent based on experimentally obtained viscosity and density data of oleyl alcohol. At 290 °C, coincident with the nucleation and growth of plasmonic-doped metal oxide nanocrystals, solvent viscosity decreases to a corresponding Reynolds number of 9.2 × 10⁵, indicating that the dramatic viscosity reduction in oleyl alcohol above synthetic temperature batch reaction conditions drives a sharp increase in Reynolds number into a strongly turbulent mixing regime at synthetically relevant temperatures. The simulation results revealed that the scale-up process induces notable variations in shear rate distribution, local turbulence intensity, and overall mixing efficiency. These findings suggest that understanding rheological transitions under scale-up conditions is essential for optimizing nanoparticle synthesis and dispersion uniformity in industrial applications. Full article

This study introduces five types of wax materials to replace traditional Sasobit warm mix agents (WMAs), aiming to reduce the aging performance of high-viscosity modified asphalt (HMA) under high temperatures and optimize wax-based WMAs for a better warm mix effect and more stable performance of HMA. In this study, styrene–butadiene–styrene (SBS) modifier was first used to prepare HMA, and then wax materials were added to prepare HMA. Thin-Film Oven Tests (TFOTs) and Pressure Aging Vessel (PAV) aging tests were conducted, followed by dynamic shear rheology (DSR) tests, to study the high-temperature rheological properties of each warm mix HMA. Fourier-transform infrared spectroscopy (FTIR) tests and fluorescence microscopy were used to observe the microstructures of the asphalt. The results show that all six wax materials exhibited good warm mix effects, among which refined Fischer–Tropsch Wax 1 (RFW1) outperforms conventional Sasobit WMA in terms of warm mix effect, high-temperature rheological properties, and anti-aging performance, indicating its potential to replace Sasobit in engineering applications. Full article

The transition to sustainable thermosetting resins is frequently hindered by the trade-off between high bio-based content and processability. This study reports a novel strategy in developing a highly bio-based, styrene-free unsaturated polyester resin (UPR) by leveraging maltodextrin-derived mixed esters dissolved in dimethyl itaconate (DMI). Unlike conventional polysaccharide-based systems that suffer from extreme viscosity, our functionalized prepolymer–DMI system achieves a low-viscosity curing solution without requiring petroleum-derived diluents such as styrene. Fourier-transform infrared spectroscopy confirmed the formation of a robust crosslinked network via the complete consumption of C=C bonds. Consequently, the cured resin exhibits exceptional thermal and mechanical performance, outperforming many existing bio-based analogs: a glass transition temperature (T_g) reaching 141 °C, a decomposition onset near 250 °C, and superior dimensional stability with a linear thermal expansion coefficient as low as 77 ppm/°C. Demonstrating a fully renewable, easy-to-process formulation with a flexural strength of 44 MPa, this work provides a design template for the next generation of high-performance, eco-friendly industrial thermosets. Full article

The growing demand for environmentally responsible lubricants motivates the use of bio-based base stocks and benign solid additives. This study assesses the tribological performance of two Amazonian vegetable oils, Carapa guianensis (andiroba) and Copaifera spp. (copaiba resin) and a paraffinic mineral oil (PNL30) formulated with different zinc oxide (ZnO) particles, namely nanocrystals and microcrystals, at 0.01, 0.05, and 0.10 wt.%. Reciprocating sliding tests, coupled with 3D profilometry, viscosity, and sedimentation analyses, were used to link dispersion stability with friction and wear responses. A preliminary stability screening constrained the practical loading window to ≤0.10 wt.% for reproducible suspensions. Performance depended on the interplay between particle type and base-oil chemistry. Andiroba exhibited the most pronounced gains, with ZnO microcrystals near 0.05 wt.% delivering the best friction outcomes and the largest wear reductions (up to ~35%). In copaiba resin oil, nanocrystals produced small, sometimes non-significant improvements, whereas microcrystals tended to worsen wear consistent with abrasive third-body effects in a less polar matrix. In PNL30, the overall benefits were modest: nanocrystal additions generally increased wear, whereas microcrystals particularly at the highest loading 0.10 wt.% achieved a 36.4% reduction in SWR, representing a measurable and statistically significant improvement in wear resistance. These results highlight that eco-efficient lubricant design should co-optimize particle characteristics and dosage with base-oil polarity and film-forming tendencies, prioritizing dispersion stability alongside tribological targets. Full article

The control systems for models described by non-commensurate fractional-order differential equations are based on their transformation into large commensurate-order systems, which impose difficulties in determining control laws. In this context, in this paper, a new control method for this class of systems is proposed. The results obtained are based on Lyapunov methods for differential equations with fractional exponents and on the application of the Yakubovich–Kalman–Popov lemma adapted for this class of systems. The stability criterion is presented as a frequency criterion and represented graphically by familiar frequency plots similar to those of the Nyquist or Popov type. If the parameters that define the model can be defined in a closed domain, the frequency criterion can be interpreted as “Popov’s circle criterion”. The two numerical applications present two important cases. The first studies the stability criterion in the case where the viscosity coefficients determine non-commensurate fractional-order exponents in the dynamic model of the system. The second example studies the complex problem of the human–machine system in which the human model imposes dynamics determined by non-commensurate fractional-order systems. The proposed investigation methods allow for a reduction in computational effort by several orders of magnitude for non-commensurate fractional-order systems, eliminate stability conditions that use matrix-based criteria for large-scale systems, and introduce standard frequency-domain criteria. Full article

To address the problems of strong roof integrity, severe energy accumulation, and difficult caving in thick and hard roofs, a three-dimensional numerical study on fracture propagation and pressure-relief control durisng segmented hydraulic fracturing was carried out based on the engineering geological conditions of the 6125-1 working face at the Haishiwan Coal Mine, Shaanxi Province, China. using the ABAQUS finite element platform coupled with Ins-coh cohesive elements. A systematic analysis was conducted to elucidate the effects of elastic modulus, Poisson’s ratio, injection rate, and fluid viscosity on fracture initiation, stress evolution, and fractured volume. The results show that for every 10 GPa increase in elastic modulus, the average fractured volume decreases by 8%, and the fracture width exhibits a marked reduction; increasing Poisson’s ratio enhances the lateral deformation compatibility of the rock mass, raising the fracture width and volumetric growth rate by approximately 3% and 5%, respectively, although an excessively high Poisson’s ratio induces stress diffusion and reduces fracture stability. When the injection rate increases from 0.01 m³/s to 0.025 m³/s, the fractured volume increases by about 160%, and the maximum fracture width increases by 43%, whereas increasing fluid viscosity exerts a limited influence on volumetric growth but is conducive to stabilizing fracture morphology. Field observations via borehole imaging and seepage confirm full fracture connectivity within the roof and the formation of a continuous rupture zone, promoting timely roof breakage and caving along the dip direction and thereby creating favorable conditions for reducing rockburst hazards at the working face. This study clarifies the mechanical mechanisms and multi-parameter coupling laws governing hydraulic fracture propagation in thick and hard roofs, providing a theoretical basis and engineering reference for roof pressure-relief control and rockburst-resistant design under similar geological conditions. Full article

Textile-to-textile recycling is increasingly recognised as essential to reduce the environmental footprint of the textile sector, yet fibre-to-fibre routes remain constrained by complex composition of fibre blends, chemical finishes and the degradation of fibre quality during repeated processing. This review provides a comprehensive overview of recycling strategies for major textile fibres, cotton, polyester, viscose, polyamide, and wool, from a fibre-level perspective, highlighting the relationships between fibre chemistry, structure, and recyclability. Mechanical, chemical, and biological recycling routes are analysed with a particular focus on fibre integrity, yarn and fabric performance, and their suitability for industrial textile applications rather than solely on waste management aspects. The review also examines industrial initiatives and emerging technologies driving the transition towards circular textile systems, critically identifying key barriers such as feedstock heterogeneity, fibre blending, and downcycling. Building on existing review articles on textile recycling, this work synthesises current knowledge on fibre-to-fibre routes, compares different process options in terms of recycled-fibre quality and scalability, and highlights remaining technological and implementation gaps. To advance textile circularity, integrated recycling frameworks are proposed that align material design, process optimisation, and policy instruments. This work contributes a cross-disciplinary understanding of how fibre-level innovation can enable resource-efficient, closed-loop textile production, offering a roadmap for future sustainable materials engineering in industrial textile systems. Full article