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Sodium (Na) metal batteries have attracted recent attention due to their low cost and high abundance of Na. However, the advancement of Na metal batteries is impeded due to key challenges such as dendrite growth, solid electrolyte interphase (SEI) fracture, and low Coulombic efficiency. This study examines the coupled electro-chemo-mechanical interactions governing the electrodeposition stability and morphological evolution at the Na/electrolyte interface. The SEI heterogeneities influence transport and reaction kinetics leading to the formation of current and stress hotspots during Na plating. Further, it is demonstrated that the heterogeneity-induced Na metal evolution and its influence on the stress distribution critically affect the mechanical overpotential, contributing to a faster SEI failure. The analysis reveals three distinct failure mechanisms-mechanical, transport, and kinetic-that govern the onset of instabilities at the interface. Finally, a comprehensive comparative study of SEI failure in Na and lithium (Li) metal anodes illustrates that the electrochemical and mechanical characteristics of the SEI are crucial in tailoring the anode morphology and interface stability. This work delineates mechanistic stability regimes cognizant of the SEI attributes and underlying failure modes and offers important guidelines for the design of artificial SEI layers for stable Na metal electrodes.
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In the present work, phosphorylated cellulose (PC) gel has been produced following an environmentally benign approach using agro-based chemicals with improved yield. The PC gels produced were transparent, negatively charged with high consistency, charge content (1133.33 mmol/kg), degree of substitution (DS) of 0.183 and increased yield (>87 %). The XPS and EDS analysis confirms the covalently bonded phosphate groups at weight percent of 9.42 % and 11.01 %, respectively. The life cycle assessment (LCA) shows that PC gel production via the phosphorylation route is an ecologically favourable strategy compared with traditional TEMPO oxidation, resulting in 1.67 times lower CO2 emission. The rheological studies of PC gels show shear-thinning behaviour with improved 3D printability followed by heat-induced crosslinking of phosphate groups. The mechanistic insights for the condensation of phosphate to form a phosphoric ester group during cross-linking were evaluated through 31P solid-state NMR and XPS studies. Interestingly, the 3D-printed structures showed high structural stability under both compression and tensile load in both dry and wet conditions, with high water absorption (5408.33 %) and swelling capacity of 700 %. The structures show improved methylene blue (MB) remediation capabilities with a maximum removal efficiency of 99 % for 10-200 mg/L and more than seven times reusability. This work provides a green, facile and energy-efficient strategy for fabricating PCs with easy processability through additive manufacturing techniques for producing value-added products, opening up new avenues for high-performance applications.
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Bioimpresión , Celulosa , Celulosa/química , Bioimpresión/métodos , Impresión Tridimensional , Geles , Fosfatos , Andamios del Tejido/química , Ingeniería de Tejidos/métodosRESUMEN
As solid-state batteries (SSBs) with lithium (Li) metal anodes gain increasing traction as promising next-generation energy storage systems, a fundamental understanding of coupled electro-chemo-mechanical interactions is essential to design stable solid-solid interfaces. Notably, uneven electrodeposition at the Li metal/solid electrolyte (SE) interface arising from intrinsic electrochemical and mechanical heterogeneities remains a significant challenge. In this work, the thermodynamic origins of mechanics-coupled reaction kinetics at the Li/SE interface are investigated and its implications on electrodeposition stability are unveiled. It is established that the mechanics-driven energetic contribution to the free energy landscape of the Li deposition/dissolution redox reaction has a critical influence on the interface stability. The study presents the competing effects of mechanical and electrical overpotential on the reaction distribution, and demarcates the regimes under which stress interactions can be tailored to enable stable electrodeposition. It is revealed that different degrees of mechanics contribution to the forward (dissolution) and backward (deposition) reaction rates result in widely varying stability regimes, and the mechanics-coupled kinetics scenario exhibited by the Li/SE interface is shown to depend strongly on the thermodynamic and mechanical properties of the SE. This work highlights the importance of discerning the underpinning nature of electro-chemo-mechanical coupling toward achieving stable solid/solid interfaces in SSBs.
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Protein-based biomaterials, particularly amyloids, have sparked considerable scientific interest in recent years due to their exceptional mechanical strength, excellent biocompatibility and bioactivity. In this work, we have synthesized a novel amyloid-based composite hydrogel consisting of bovine serum albumin (BSA) and aloe vera (AV) gel to utilize the medicinal properties of the AV gel and circumvent its mechanical frangibility. The synthesized composite hydrogel demonstrated an excellent porous structure, self-fluorescence, non-toxicity, and controlled rheological properties. Moreover, this hydrogel possesses inherent antioxidant and antibacterial properties, which accelerate the rapid healing of wounds. The in vitro wound healing capabilities of the synthesized composite hydrogel were evaluated using 3T3 fibroblast cells. Moreover, the efficacy of the hydrogel in accelerating chronic wound healing via collagen crosslinking was investigated through in vivo experiments using a diabetic mouse skin model. The findings indicate that the composite hydrogel, when applied, promotes wound healing by inducing collagen deposition and upregulating the expression of vascular endothelial growth factor (VEGF) and its receptors. We also demonstrate the feasibility of the 3D printing of the BSA-AV hydrogel, which can be tailored to treat various types of wound. The 3D printed hydrogel exhibits excellent shape fidelity and mechanical properties that can be utilized for personalized treatment and rapid chronic wound healing. Taken together, the BSA-AV hydrogel has great potential as a bio-ink in tissue engineering as a dermal substitute for customizable skin regeneration.
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Aloe , Diabetes Mellitus , Ratones , Animales , Hidrogeles/farmacología , Hidrogeles/química , Aloe/química , Aloe/metabolismo , Albúmina Sérica Bovina , Factor A de Crecimiento Endotelial Vascular/metabolismo , Cicatrización de Heridas , ColágenoRESUMEN
The Eclipta alba plant is considered hepatoprotective, owing to its phytoconstituents wedelolactone. In the current study, effect of elevated ultraviolet-B (eUV-B) radiation was investigated on biochemical, phytochemical, and antioxidative enzymatic activities of E. alba (Bhringraj) plant. The UV-B exposure resulted in an increase in oxidative stress, which has caused an imbalance in phytochemical, biochemical constituents, and induced antioxidative enzymatic activities. It was observed that the UV-B exposure promoted wedelolactone yield by 23.64%. Further, the leaf extract of UV-B-exposed plants was used for the synthesis of carbon quantum dots (CQDs) using low cost, one-step hydrothermal technique and its biocompatibility was studied using in vitro MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay on HepG2 liver cell line. It revealed no toxicity in any treatment groups in comparison to the control. Both CQDs and leaf extract were orally administered to the golden hamster suffering from alcohol-induced liver cirrhosis. In the morphometric study, it was clearly observed that a combination of UV-B-exposed leaf extract and synthesized CQDs delivered the best result with maximum recovery of liver tissues. The present study reveals the positive impact of UV-B exposure on the medicinally important plant, increased yield of wedelolactone, and its enhanced hepatoprotective efficacy for the treatment of damaged liver tissues.
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Eclipta , Puntos Cuánticos , Animales , Cricetinae , Extractos Vegetales/farmacología , Mesocricetus , Antioxidantes/farmacología , Cirrosis Hepática , Carbono/farmacologíaRESUMEN
Solid-state batteries (SSBs) employing a lithium metal anode are a promising candidate for next-generation energy storage systems, delivering higher power and energy densities. Interfacial instabilities due to non-uniform electrodeposition at the anode-solid electrolyte (SE) interface pose major constraints on the safety and endurance of SSBs. In this regard, non-uniform kinetic interactions at the anode-SE interface which are derived from cathode microstructural heterogeneity can have significant impact on anode stability. In this work, we present a comprehensive insight into microstructural heterogeneity-driven cathode-anode cross-talk and delineate the role of cathode architecture and SE separator design in dictating reaction heterogeneity at the anode-SE interface. We show that intrinsic and extrinsic parameters, such as cathode loading, separator thickness, particle morphologies of active material and SE, and temperature can have significant impact on reaction heterogeneity at the anode-SE interface and thus govern anode stability. Tradeoff between energy density and anode stability while achieving higher cathode loading and thinner SE separators is highlighted, and potential strategies to mitigate this problem are discussed. This work provides fundamental insights into cathode-anode cross-talk involving interfacial heterogeneities and enhancement in energy densities of SSBs via electrode engineering.
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The COVID-19 is a pandemic caused by the SARS-CoV-2 virus, has instigated major health problems and prompted WHO to proclaim a worldwide medical emergency. The knowledge of SARS-CoV-2 fundamental structure, aetiology, its entrance mechanism, membrane hijacking and immune response against the virus, are important parameters to develop effective vaccines and medicines. Liquid crystals integrated nano-techniques and various nanoformulations were applied to tackle the severity of the virus. It was reported that nanoformulations have helped to enhance the effectiveness of presently accessible antiviral medicines or to elicit a fast immunological response against COVID-19 virus. Applications of liquid crystals, nanostructures, nanoformulations and nanotechnology in diagnosis, prevention, treatment and tailored vaccine administration against COVID-19 which will help in establishing the framework for a successful pandemic combat are reviewed. This review also focuses on limitations associated with liquid crystal-nanotechnology based systems and suggests the possible ways to address these limitations. Also, topical advancements in the ground of liquid crystals and nanostructures established diagnostics (nanosensor/biosensor) are discussed in detail.
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The understanding of the genesis of life-threatening cancer and its invasion calls for urgent development of novel technologies for real-time observations, early diagnosis, and treatment. Quantum dots (QDs) grabbed the spotlight in oncology owing to their excellent photostability, bright fluorescence, high biocompatibility, good electrical and chemical stability with minimum invasiveness. Recently, carbon QDs (CQDs) have become popular over toxic inorganic QDs in the area of bioimaging, biosensing, and drug delivery. Further, CQDs derived from natural sources like biomolecules and medicinal plants have drawn attention because of their one-pot, low-cost and ease of synthesis, along with remarkable tunable optical properties and biocompatibility. This review introduces the synthesis and properties of CQDs derived from natural sources, focusing on the applicability of CQD-based technologies as nano-theranostics for the diagnosis and treatment of cancer. Furthermore, the current issues and future directions for the transformation of CQDs-based nanotechnologies to clinical applications are highlighted.
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Solid-state batteries (SSBs) hold the potential to enhance the energy density, power density, and safety of conventional lithium-ion batteries. The theoretical promise of SSBs is predicated on the mechanistic design and comprehensive analysis of various solid-solid interfaces and microstructural features within the system. The spatial arrangement and composition of constituent phases (e.g., active material, solid electrolyte, binder) in the solid-state cathode dictate critical characteristics such as solid-solid point contacts or singularities within the microstructure and percolation pathways for ionic/electronic transport. In this work, we present a comprehensive mesoscale discourse to interrogate the underlying microstructure-coupled kinetic-transport interplay and concomitant modes of resistances that evolve during electrochemical operation of SSBs. Based on a hierarchical physics-based analysis, the mechanistic implications of solid-solid point contact distribution and intrinsic transport pathways on the kinetic heterogeneity is established. Toward designing high-energy-density SSB systems, the fundamental correlation between active material loading, electrode thickness and electrochemical response has been delineated. We examine the paradigm of carbon-binder free cathodes and identify design criteria that can facilitate enhanced performance with such electrode configurations. A mechanistic design map highlighting the dichotomy in kinetic and ionic/electronic transport limitations that manifest at various SSB cathode microstructural regimes is established.
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The behaviour and health of lubricated systems in various natural and artificial settings are often characterized by their load bearing capacity. This capacity stemming from the lift force associated with confined fluid flow can be significantly altered due to surface compliance and electrokinetic effects. Here, we highlight the influence of finite size of the ionic species participating in electrokinetic transport with substrate compliance in determining the electromechanical characteristics of lubricated systems. With these new considerations, anomalous trends previously observed for the load bearing capacity corresponding to high values of zeta potential are corrected. Simultaneously, trends associated with the finite ionic size are also found to be reversed, but fall in line with the consistent theory. Importantly, despite an intricate interplay among the various influences - electrokinetic, hydrodynamic, geometric, and elastic - previously established trends due to geometric (non-parallel slider geometry) and elastic effects are found to persist. Specifically, in the presence of electrokinetic effects, an increase in the obliqueness of the slider geometry results in lower values of load bearing capacity while an increase in the stiffness leads to higher values. These results point to a certain robustness in the overall theory and it is hoped that they can contribute to better practical designs of slider bearings and an improved understanding of lubricated sliding surfaces in biological settings.