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A deterministic, bright, room-temperature stable single-photon source (SPS) has been a major demand in the field of quantum photonics. Here, using computational and analytical techniques, we showed that the Mie-scattering moments of an all-dielectric cavity-cum-antenna help in shaping the spontaneous emission process of an embedded point-dipole emitter, the nanodiamond-based NV − and SiV color centers here. Our resonator-cum-antenna design comprises two top and bottom TiO 2 cylinders with a sandwiched polyvinyl alcohol (PVA) layer enclosing the nanodiamond crystal. The Cartesian multi-polar decomposition of the Mie-scattering moments of the sandwiched PVA layer (enclosing the dipole emitter) with subwavelength scale thickness showed strong electric-dipole (ED) resonance. This resulted in significant field confinement, making the PVA layer to act as a cavity, providing a Purcell enhancement of more than an order of magnitude for all dipole orientations. The top and bottom TiO 2 cylinders were observed to act as an antenna, and the far-field radiation pattern of the embedded dipole-emitter is controlled by the Mie-scattering moments of the TiO 2 cylinders. The radiation directionality along the vertical directions was found to be maximum at the Kerker point (electric dipole moment, ED = magnetic dipole moment), the collection efficiency (CE) being about 80%. For dipole emission coupled to the antenna, the quantum efficiency was observed to increase to a high value of 0.98 for nanodiamond NV − center, very close to an ideal case of purely radiative emission. Our scheme is shown to be universal and can be applied to any solid-state-based quantum emitters, for generating on-demand SPS for quantum-photonic applications. [ABSTRACT FROM AUTHOR]

The charge transport in conducting polymer blends of poly(3,4-ethylenedioxythiophene):poly(styrene-sulfonate) [PEDOT:PSS] and polyvinyl alcohol (PVA) at 75, 50, 25, and 12 vol. % of PEDOT:PSS is investigated in the temperature range of 300–4.2 K. The scaling fit to percolative transport [σ ∝ |f − fc|t] shows that fc is around 10% and t = 2. The temperature dependent conductivity varies from the critical regime of metal–insulator transition to variable range hopping, along with the alterations in the networks of PEDOT:PSS in PVA. The variation in the exponent (n) in electric field dependent conductivity is more significant as the volume fraction of PEDOT:PSS decreases. The value of n decreases as the thermal contribution to transport dominates, showing the competing roles of both field and temperature. [ABSTRACT FROM AUTHOR]

Hydrogel electrolytes are an integral part of flexible solid-state supercapacitors. To further improve the low ionic conductivity, large interfacial resistance and poor cycling stability for hydrogel electrolytes, the V4C3Tx MXene-enhanced polyvinyl alcohol hydrogel electrolyte was fabricated to enhance its mechanical and electrochemical performance. The high-conductivity V4C3Tx MXene (16,465.3 S m−1) bonding transport network was embedded into the PVA-H2SO4 hydrogel electrolyte (PVA- H2SO4-V4C3Tx MXene). Results indicate that compared to the pure PVA-H2SO4 hydrogel electrolyte (105.3 mS cm−1, 48.4%@2,800 cycles), the optimal PVA-H2SO4-V4C3Tx MXene hydrogel electrolyte demonstrates high ionic conductivity (133.3 mS cm−1) and commendable long-cycle stability for the flexible solid-state supercapacitors (99.4%@5,500 cycles), as well as favorable mechanical flexibility and self-healing capability. Besides, the electrode of the flexible solid-state supercapacitor with the optimal PVA-H2SO4-V4C3Tx MXene hydrogel as the solid-state electrolyte has a capacitance of 370 F g−1 with almost no degradation in capacitance even under bending from 0° to 180°. The corresponding energy density for flexible device is 4.6 Wh kg−1, which is twice for that of PVA-H2SO4 hydrogel as the solid-state electrolyte. [ABSTRACT FROM AUTHOR]

This study evaluates the structural performance of Polyvinyl Alcohol Cementitious Composites (PVCC)-layered reinforced concrete beams with coal ash under static loading. Experimental investigations included first crack load, ultimate load, load-deflection behavior, ductility, stiffness, and energy absorption. Results highlight the influence of Polyvinyl Alcohol-(PVA) fiber dosage on structural behavior. The control specimen exhibited an initial crack load of 80kN, with subsequent specimens showing varied crack initiation loads influenced by PVA fiber content. Optimal performance was observed at 1.2% PVA fiber dosage, with higher dosages leading to earlier crack initiation. Ultimate load carrying capacity increased with PVA fiber addition, reaching a peak at 1.2% dosage before slight decreases occurred with higher dosages. Load-deflection behavior demonstrated the superior performance of PVCC layered beams, particularly specimen BP3, attributed to optimal fiber content. Ductility, stiffness, and energy absorption increased with PVA fiber reinforcement, with 1.2% dosage yielding optimal results. Excessive fiber content led to diminishing returns. Energy index analysis revealed superior energy dissipation in specimens with higher PVA fiber content, emphasizing the effectiveness of fiber reinforcement in enhancing structural performance. Overall, the study underscores the importance of optimizing PVA fiber dosage to maximize structural resilience and load-bearing capacity in PVCC-layered concrete beams with coal ash. [ABSTRACT FROM AUTHOR]

The usage of transition metal carbide-based electrocatalysts has proven to be an efficient and effective strategy for enhancing the kinetics of water splitting reactions encompassing the generation of hydrogen (hydrogen evolution reaction, HER) and oxygen (oxygen evolution reaction, OER). In this investigation, we have prepared a composite material by integrating Cr2CTx MXene (derived from Cr2AlC MAX phase) and polyvinyl alcohol (PVA) through electrospinning technique. Carbonization of the MXene-PVA nanofibers resulted in the formation of Cr2CTx/carbon nanofiber (Cr2CTx/CNF) that exhibits high porosity, stability, surface area, and electrocatalytic activity. Systematic examination and optimization for the electrocatalytic water splitting reaction reveales outstanding performance, characterized by substantially lower overpotentials of 265 mV and 250 mV at the constant current density of 10 mA cm−2 with lower Tafel slope values of 85 mV dec−1 and 52 mV dec−1 for HER and OER, respectively. Moreover, this work presents a novel strategy for fabricating non-precious electrocatalyst Cr2CTx/CNF through a cost-effective and straightforward electrospinning and carbonization process, advancing electrocatalytic water splitting applications, especially for oxygen evolution reactions. [ABSTRACT FROM AUTHOR]

Polyvinyl alcohol (PVA) was crosslinked with a homologous series of four different dicarboxylic acids, HOOC(CH2) n‐2COOH (n = 2 to 5) viz. oxalic acid (OA; C2), malonic acid (MA; C3), succinic acid (SA; C4) and glutaric acid (GA; C5) containing odd and even number of carbon atoms. The characterization and assessment of synthesized crosslinked films were done using ATR‐FTIR, XRD, SEM, AFM, DSC, rheology, percent swelling and sessile drop contact angle. The odd‐even effect of dicarboxylic acids was observed to significantly influence the physicochemical properties of PVA when employed as a crosslinker. PVA films crosslinked using dicarboxylic acids containing an even number of carbon atoms, displayed translucency, roughness, and an irregular matrix. In contrast, films incorporating an odd number of carbon atoms were transparent, homogenous, and densely packed. Furthermore, films containing even acids exhibited relatively lower crystallinity, lower melting temperature (Tm) and displayed an unexpected irregular trend in swelling as crosslinker concentration increased compared to films containing dicarboxylic acids with an odd number of carbon atoms which exhibits a consistent swelling with increasing crosslinker concentration. These results are attributed to the difference in the solubility and crystal structures of the odd‐even series of dicarboxylic acids. [ABSTRACT FROM AUTHOR]

AbstractThe current study aimed to the preparation of graphene oxide impregnated chitosan– polyvinyl alcohol hybrid beads (GO/CS-PVA) for the removal of Reactive Black 5 (RB5) dye from wastewater solutions, presenting them as a cost-effective alternative for wastewater treatment. These hybrid beads were fabricated using a dripping technique in an aqueous solution. The surface and structure of the material before and after adsorption process were studied by analyzing FTIR spectroscopy and Scanning electron microscope (SEM) as well as adsorption capacity was also evaluated. The results proved the successful synthesis of GO/CS-PVA beads and elucidated the physical adsorption mechanism of RB5. SEM images revealed uniform spherical beads with a rough surface, approximately 752 μm in diameter. Additionally, the evaluation of adsorption capacity showed that the optimum condition for RB5 adsorption is at pH = 3 while the kinetic investigations revealed that the adsorption process adhered to the pseudo-second-order model, indicating a chemisorption reaction. Furthermore, an increase in temperature from 25 to 65 °C enhanced the maximum adsorption capacity of GO/CS-PVA beads by 34%. The cytotoxic effect of the hybrid as measured on adipose derived stem cells via the MTT assay was negligible. In conclusion, it was proved that the eco-friendly GO/CS-PVA beads adsorbents can efficiently remove RB5 from wastewater in practical applications. [ABSTRACT FROM AUTHOR]

Cellulose‐based aerogels possess satisfactory sustainability, porosity, and resilience, which are promising materials to replace traditional petroleum‐based foams. However, the viscous aggregation formed between hydrophilic fibers and the pore collapse caused by weak support force pose challenges for their further applications. Here, a load‐bearing structure‐inspired cellulose‐based aerogel is innovatively developed with excellent elasticity and water tolerance through surface‐interface modulation. Specifically, cellulose and polyvinyl alcohol (PVA) form interwoven skeletons by non‐directional freeze drying. Crucially, the rhamnolipid surfactant assists in forming stable and uniform bubbles, and drives the regularization of frame structure during the freezing process, promoting the construction of refined mechanical structures. Besides, the interfacial enhancement by esterification reaction of citric acid and the encapsulation by hydrophobic silane via chemical vapor deposition endow aerogels with better resilience and water tolerance. The as‐prepared aerogels can withstand intensive compression cycle tests and possess the ability to rebound over 10 times underwater. Even after 12 h wet treatment, the strain and stress loss respectively decrease by ≈55.5% and ≈14% compare with the initial unregulated aerogels after 500 cycles of 80% compression. Surprisingly, they have excellent cushioning performance beyond expanded polystyrene (EPS) and expanded polyethylene (EPE) in simulated road transportation packaging applications, indicating their potential in new‐generation cushioning materials. [ABSTRACT FROM AUTHOR]

Poly(3,4‐ethylenedioxythiophene): poly(styrene sulfonate) (PEDOT: PSS) is a promising material for organic thermoelectric (TE) applications. However, it is challenging to achieve PEDOT: PSS composites with stretchable, self‐healable, and high TE performance. Furthermore, some existing self‐healing TE materials employ toxic reagents, posing risks to human health and the environment. In this study, a novel intrinsically self‐healable and wearable composite is developed by incorporating environmentally friendly, highly biocompatible, and biodegradable materials of polyvinyl alcohol (PVA) and citric acid (CA) into PEDOT: PSS. This results in the formation of double hydrogen bonding networks among CA, PVA, and PEDOT: PSS, inducing microstructure alignment and leading to simultaneous enhancements in both TE performance and stretchability. The resulting composites exhibit a high electrical conductivity and power factor of 259.3 ± 11.7 S·cm−1, 6.9 ± 0.4 µW·m−1·K−2, along with a tensile strain up to 68%. Furthermore, the composites display impressive self‐healing ability, with 84% recovery in electrical conductivity and an 85% recovery in tensile strain. Additionally, the temperature and strain sensors based on the PEDOT: PSS/PVA/CA are prepared, which exhibit high resolution suitable for human–machine interaction and wearable devices. This work provides a reliable and robust solution for the development of environmentally friendly, self‐healing and wearable TE thermoelectrics. [ABSTRACT FROM AUTHOR]

Flexible electrochromic devices (FECDs) are widely explored for diverse applications including wearable electronics, camouflage, and smart windows. However, the manufacturing process of patterned FECDs remains complex, costly, and non‐customizable. To address this challenge, a strategy is proposed to prepare integrated FECDs via multi‐material direct writing 3D printing. By designing novel viologen/polyvinyl alcohol (PVA) hydrogel inks and systematically evaluating the printability of various inks, seamless interface integration can be achieved, enabling streamlined manufacturing of patterned FECDs with continuous production capabilities. The resultant 3D‐printed FECDs exhibit excellent electrochromic and mechanical properties, including high optical contrast (up to 54% at 360 nm), nice cycling stability (less than 5% electroactivity reduction after 10 000 s), and mechanical stability (less than 19% optimal contrast decrease after 5000 cycles of bending). The potential applications of these 3D‐printed hydrogel‐based FECDs are further demonstrated in wearable electronics, camouflage, and smart windows. [ABSTRACT FROM AUTHOR]

Burn wounds are associated with infections, drug resistance, allergic reactions, odour, bleeding, excess exudates, and scars, requiring prolonged hospital stay. It is crucial to develop wound dressings that can effectively combat allergic reactions and drug resistance, inhibit infections, and absorb excess exudates to accelerate wound healing. To overcome the above-mentioned problems associated with burn wounds, SA/PVA/PLGA/Capparis sepiaria and SA/PVA/Capparis sepiaria nanofibers incorporated with Capparis sepiaria plant extract were prepared using an electrospinning technique. Fourier-transform infrared spectroscopy confirmed the successful incorporation of the extract into the nanofibers without any interaction between the extract and the polymers. The nanofibers displayed porous morphology and a rough surface suitable for cellular adhesion and proliferation. SA/PVA/PLGA/Capparis sepiaria and SA/PVA/Capparis sepiaria nanofibers demonstrated significant antibacterial effects against wound infection-associated bacterial strains: Pseudomonas aeruginosa, Enterococcus faecalis, Mycobaterium smegmatis, Escherichia coli, Enterobacter cloacae, Proteus vulgaris, and Staphylococcus aureus. Cytocompatibility studies using HaCaT cells revealed the non-toxicity of the nanofibers. SA/PVA/PLGA/Capparis sepiaria and SA/PVA/Capparis sepiaria nanofibers exhibited hemostatic properties, resulting from the synergistic effect of the plant extract and polymers. The in vitro scratch wound healing assay showed that the SA/PVA/Capparis sepiaria nanofiber wound-healing capability is more than the plant extract and a commercially available wound dressing. The wound-healing potential of SA/PVA/Capparis sepiaria nanofiber is attributed to the synergistic effect of the phytochemicals present in the extract, their porosity, and the ECM-mimicking structure of the nanofibers. The findings suggest that the electrospun nanofibers loaded with Capparis sepiaria extract are promising wound dressings that should be explored for burn wounds. [ABSTRACT FROM AUTHOR]

Itraconazole (ITZ) is one of the broad-spectrum antifungal agents for treating fungal keratitis. In clinical use, ITZ has problems related to its poor solubility in water, which results in low bioavailability when administered orally. To resolve the issue, we formulated ITZ into the inclusion complex (ITZ-IC) system using β-cyclodextrin (β-CD), which can potentially increase the solubility and bioavailability of ITZ. The molecular docking study has confirmed that the binding energy of ITZ with the β-CD was −5.0 kcal/mol, indicating a stable conformation of the prepared inclusion complex. Moreover, this system demonstrated that the inclusion complex could significantly increase the solubility of ITZ up to 4-fold compared to the pure drug. Furthermore, an ocular drug delivery system was developed through dissolving microneedle (DMN) using polyvinyl pyrrolidone (PVP) and polyvinyl alcohol (PVA) as polymeric substances. The evaluation results of DMN inclusion complexes (ITZ-IC-DMN) showed excellent mechanical strength and insertion ability. In addition, ITZ-IC-DMN can dissolve rapidly upon application. The ex vivo permeation study revealed that 75.71% (equivalent to 3.79 ± 0.21 mg) of ITZ was permeated through the porcine cornea after 24 h. Essentially, ITZ-IC-DMN exhibited no signs of irritation in the HET-CAM study, indicating its safety for application. In conclusion, this study has successfully developed an inclusion complex formulation containing ITZ using β-CD in the DMN system. This approach holds promise for enhancing the solubility and bioavailability of ITZ through ocular administration. [ABSTRACT FROM AUTHOR]

The autoclaved aerated concrete (AAC) is a porous lightweight material. Its internal pore structure is a crucial technical feature that affects its performance. The effects of different types of foam stabilizers (cellulose ether, polyvinyl alcohol, soap powder and calcium stearate) on the compressive strength, dry density, dry wet cycle resistance, insulation performance and microstructure of iron tailings autoclaved aerated concrete (ITS-AAC) were investigated. The hydration products and microstructures were analyzed by X-ray diffraction and scanning electron microscopy. The mechanisms of the actions of the foam stabilizers were then revealed. It was shown that among the four foam stabilizers, the polyvinyl alcohol-modified ITS-AAC had the highest proportion of pores, with a smaller internal area and no apparent pore connectivity. These features had the most significant impacts on ITS-AAC performance and microstructure. Furthermore, the modified ITS-AAC showed the best performance for a polyvinyl alcohol content of 1.0%, with a compressive strength increase of 30.2%, a dry wet cycle coefficient increase of 63.9% for the 15th cycle, and a dry density decrease of 7.7% (with respect to the unmodified ITS-AAC),the thermal conductivity decreased by 42.6%.This was due to the fact that many highly active hydroxyl groups in polyvinyl alcohol would bind to water molecules with hydroxyl hydrogen bonds, thereby directly competing with the host hydrate molecules. The water molecules that were adsorbed on the surface of the hydrophilic SiO2 formed hydrogen bonds with the hydroxyl groups in the formation of a stable polyvinyl alcohol polymer. In addition, due to the excellent film-forming properties of polyvinyl alcohol after dissolution, some parts of the hydration C–S–H gel product and the slurry, which did not fully participate in the reaction, were wrapped in the film-forming process. A water hardening slurry with a good network and dense spatial structure was formed. [ABSTRACT FROM AUTHOR]

Multi‐level anticounterfeiting tags have been developed using a combination of different materials. Polyvinyl alcohol (PVA) mixed with titanium dioxide (TiO2) is used to produce flexible substrates. Fluorescent Opuntia Ficus‐indica (OFI) extract dissolved with polymethyl methacrylate (PMMA) is then sprayed over the substrate to create a random, yet unique deposition of droplets. Photographs of the tags are taken under UV illumination at different angles and analyzed through the scale‐invariant feature transform (SIFT) algorithm to extract their unique features. The SIFT analysis reveals hundreds to thousands of matched features when a given tag is compared with itself, whereas this number drops to tens for different tags. To enhance the security of the tags, ITO is sputtered onto one of them in the form of a pattern formed by a patch array exhibiting a specific fingerprint at terahertz (THz) frequencies. The evaluation of ITO reflectance shows that each patch array has a unique and unpredictable response stemming from its distinct electro‐optical characteristics. The non‐deterministic response of sprayed dye droplets and ITO patches enables the realization of two‐level authentication, which is difficult to replicate at a reasonable cost. The simple manufacturing process and inexpensive materials involved make the proposed tags easily integrable into packaging. [ABSTRACT FROM AUTHOR]

The double skeleton interpenetrating network fixed the quaternary ammonium salt, and various internal conduction modes cooperated to promote the transport of hydroxide ions. [Display omitted] The alkaline solid-state electrolytes have received widespread attention for their good safety and electrochemical stability. However, they still suffer from low conductivity and poor mechanical properties. Herein, we report the synthesis of double-network featured hydroxide-conductive membranes fabricated by polyvinyl alcohol (PVA) and chitosan (CS) as the double-skeletons. Then, we implanted quaternary ammonium salt guar hydroxypropyltrimonium chloride (GG) as the OH− conductor for high-performance electrochemical devices. By virtue of the unique stripe-like structure shared from the double skeleton with a high degree of compatibility and stronger hydrogen bond interactions, the polyvinyl alcohol/chitosan-guar hydroxypropyltrimonium chloride (PCG) solid-state electrolytes achieved optimal thermal stability (> 300 °C), mechanical property (∼ 34.15 MPa), dimensional stability (at any bending angle), and high ionic conductivity (13 mS cm−1) and ion mobility number (t ion ∼ 0.90) compared with chitosan-guar hydroxypropyltrimonium chloride (CG) and polyvinyl alcohol-guar hydroxypropyltrimonium chloride (PG) electrolyte membrane. As a proof-of-concept application, the "sandwich"-type zinc-air battery (ZAB) assembled using PCG membrane as the electrolyte realized a high open-circuit voltage (1.39 V) and an excellent power density (128 mW cm−2). Notably, in addition to its long-term cycle life (30 h, 2 mA cm−2) and stable discharge plateau (12 h, 5 mA cm−2), it could even enable a flexible ZAB (F-ZAB) to readily power light-emitting diodes (LED) at any bending angle. These merits afford the PCG membrane a promising electrolyte for improving the performance of solid-state batteries. [ABSTRACT FROM AUTHOR]

The present research article demonstrates the dispersion of boehmite (BHM) nanoparticles into sericin (SER) from silk industry waste with polyvinyl alcohol (PVA) to enhance the optical, mechanical, thermal and electrical characteristics of PVA/SER blend nanocomposites prepared by a simple green synthesis. Techniques such as Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), UV visible spectroscopy, field emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HR-TEM), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were carried out for the characterization of the prepared composites. XRD revealed the increased crystallinity of the polymer blend by the reinforcement of BHM. The existence of intermolecular interactions in the blend composite was confirmed by FTIR and UV spectroscopy. The optical bandgap energy of the biopolymer blend decreases with the inclusion of BHM. The SEM and HR-TEM confirmed the homogeneous dispersion of BHM in the blend at 5 wt% loading. The glass transition temperature and thermal stability of the blend nanocomposites were significantly improved by the inclusion of BHM was deduced from DSC and TGA. The dielectric constant and AC conductivity were remarkably increased with the reinforcement of nanoparticles. The activation energy obtained from AC conductivity decreased with temperature. The mechanical properties of the blend nanocomposites (hardness, tensile strength and Young's modulus) were greatly increased in presence of BHM. The 5 wt% sample has the highest tensile strength, Young's modulus, dielectric constant, AC conductivity and optical properties, allowing it to be used to make optoelectronic devices with better charge-storing capacity and flexible-type electrochemical gadgets. [ABSTRACT FROM AUTHOR]

Loess has high water sensitivity and exhibits poor characteristics such as weak cementation and high porosity. Under heavy rainfall, loess fill slopes are prone to erosion and landslides, posing serious threats to public safety and property. In light of these serious threats, this study employed the method of spraying polyvinyl alcohol (PVA) solution to improve loess fill slopes and systematically examine its protective effects. Through field investigations and combined laboratory and outdoor tests, this study comprehensively evaluated the mechanical properties, anti-aging and anti-erosion performance of loess after PVA solution spraying. Scanning electron microscopy was used to reveal the mechanism of PVA action at the microscopic level. The results showed that after treatment with PVA solutions of varying concentrations, the mechanical properties of loess samples were significantly enhanced, while also exhibiting excellent anti-aging and water resistance performance. Additionally, PVA-treated loess fill slopes exhibited excellent rain erosion resistance. A microscopic structural analysis showed that PVA fills the internal pores of loess, strengthens inter-particle bonding, and uses its hydrophobic groups' water-repellent action to effectively enhance slope stability and erosion resistance. In conclusion, PVA treatment not only significantly enhances the protective effects of loess fill slopes but also holds important value in improving soil sustainability and environmental protection. [ABSTRACT FROM AUTHOR]

Poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS), a conductive polymer dispersion, is widely used in cathodes of solid electrolytic capacitors. However, it still suffers from performance limitations when used at high frequencies, and its withstand voltage must be improved. Herein, impregnation drying introduces a polyvinyl alcohol (PVA) coating onto alumina, which regulates the interface between the PEDOT:PSS cathode and alumina. The equivalent series resistance (ESR) of the capacitor is significantly reduced, whereas the withstand voltage is slightly improved. This study demonstrates that the presence of PVA enhances the wettability of PEDOT:PSS dispersions on alumina surfaces. Changes in the infrared peak positions of the OH and SO3H groups following the mixing of the PVA and PEDOT:PSS films, along with alterations in the thermal decomposition temperature, indicate the occurrence of crosslinking. Theoretical calculations demonstrate the presence of hydrogen bonds between the OH groups in PVA and the SO3H groups of PEDOT:PSS. Interface modulation effectively improves capacitor performance, as the capacitance ratio of capacitors with 400 V level withstand voltages increases from 97.35% to 98.85%, and the ESR at 100 kHz is significantly reduced by ≈40%. This study provides a valuable reference for the preparation of high‐performance solid electrolytic capacitors. [ABSTRACT FROM AUTHOR]

One of the few synthetic resins from petroleum-based sources that are biodegradable and can reduce the environmental pollution is polyvinyl alcohol (PVA). PVA film is non-toxic, transparent, and biocompatible in line with green ecologically friendly requirements. It is completely biodegradable and possesses good mechanical properties, chemical resistance, and gas barrier. PVA's hydroxyl groups, however, decrease its mechanical and thermal properties and make it water-soluble, which limits its use. However, it is possible to control the water solubility or absorption by partially cross-linking the polymer chains. This work aims to enhance the mechanical properties while making an insoluble film through cross-linking with oxalic acid (OA). In the present investigation, PVA film was cross-linked with OA (with variable weight percentage (wt%) of OA) to limit its ability to absorb moisture. Tensile testing was utilized to evaluate the mechanical properties of the films, revealing their ultimate tensile strength, % elongation, and Young's modulus. With increase in wt% of OA, % elongation of PVA-based films decreases, whereas maximum tensile strength was observed at 10 wt% of OA configuration. In comparison to neat PVA, the differential thermo-gravimetric analysis peak migrated towards the higher temperature side with an increase in the OA concentration. The peak value of tan δ curve also increased and shifted towards higher temperature side as the OA concentration increased. This concludes that prepared films have high damping coefficient and can absorb impact load. Finally, the films' creep-recovery behaviour was also examined in detail. To represent the potential application of these films as packaging materials, anti-microbial tests were also conducted. [ABSTRACT FROM AUTHOR]

In the food packaging industry, the developments of environmental friendly materials are still one of the challenging areas and many studies have been conducted on the improvement of mechanical and barrier properties of polyvinyl alcohol (PVA) by the incorporation of other polymer. The present study deals with the extraction of cellulose and conversion into nanocellulose (NC) from wood waste of Azadirachta indica and incorporation with polyvinyl alchol (PVA) for food packaging application. The prepared NC was characterized by FT-IR, X-ray diffraction (XRD), scanning electron microscopy (SEM), and particle size analyzer. FT-IR spectrum confirmed the removal of lignin and hemicellulose in the sample. The SEM reveals the morphology of NC which is nanometer in size, and from the particle size analyzer, the diameter of the particle was found to be 121 nm by the DLS method. The X-ray diffraction pattern showed the intensity at 2θ = 22.71 with sharp peak, which confirms the NCs are in crystalline form. The characterized NC was impregnated with polyvinyl alcohol (PVA) and the prepared NC-PVA bionanocomposite film was characterized by FT-IR that confirmed the presence of both functional groups in the film. Then, the improved mechanical properties of tensile strength (N/mm2) and elongation at break (%) were found to be 42.18 and 47.48 at 40 mg of NC concentration. The biodegradability of the films was tested in the outer environmental condition and 97% was degraded within 21 days. Hence, CNF-PVA bionanocomposite packaging material can be used for food packaging purpose in near future. [ABSTRACT FROM AUTHOR]

The increasing demand for portable and flexible energy storage devices drives the rapid development of flexible electrodes and electrolytes. Meanwhile, the free‐standing polymer electrodes face great chance and challenge. In this work, the stretchable and flexible polyaniline/carbon nanotube/poly(vinyl alcohol) electrode (PANI/CNT/PVA‐E) was fabricated by in‐situ polymerization of aniline in CNT/PVA‐E substrate, where CNT was used to enhance the conductivity and mechanical properties of the polymer electrodes. Compared with PANI/PVA, the comprehensive performance of PANI/CNT/PVA‐E was improved. In addition, the electrochemical performance and tensile property of the electrodes depended on the CNT content. The nanocomposite electrode with 0.25% of CNT possessed optimal properties with high capacitance of 248.69 mF cm−2, and 75.29% of capacity retention over 4000 charge–discharge cycles at 1 mA cm−2. It also exhibited outstanding tensile strength of 3.88 MPa and elongation up to 462.3%. Interestingly, the electrode possessed good heat driven shape memory effect. The temporary shape could be fixed at 70°C under extra force, and the fixed shape recovered within 10 s when it was reheated to the same temperature. It is concluded that the present work may contribute to the development and fabrication of flexible energy‐storage devices, portable and highly stretchable electric devices. [ABSTRACT FROM AUTHOR]

Nanofibrous membranes were developed by combining chitosan (CS), polyvinyl alcohol (PVA), and calcium chloride (CC) to incorporate curcumin (CCM) through a co‐axial electro‐spinning method to improve CCM bioavailability. The optimal parameters were PVA/CS ratio of 7:3 v/v, PVA/CCM ratio of 8:2 v/v, CC amount of 0.5 g, fiber collection distance of 15 cm, voltage value of 18 kV, and injection flow of 0.1 mL/h (both core and shell layer). The prepared PVA/CCM@CS/PVA/CC nanofiber showed smooth surfaces and uniform bead‐free morphology with core‐shell structure. The average fiber diameter was 301.55 ± 76.77 nm with a narrow distribution. Using the Korsmeyer‐Peppas kinetic release model, the nanofiber membrane effectively released ∼85% CCM at pH 7.4 over 96 h via Fickian diffusion transport mechanism. In vitro antibacterial tests demonstrated that the membrane was efficient against both Gram‐positive (Staphylococcus aureus) and Gram‐negative (Pseudomonas aeruginosa) bacteria. When compared to free CCM, the membrane improved cell survival due to its nontoxic and cytobiocompatible features. In vivo tests found that the membrane significantly improved healing in incised‐wound rats, reducing inflammation, fibroblast proliferation, and collagen deposition. These findings indicate that the novel PVA/CCM@CS/PVA/CC nanofiber membrane, which has numerous biological functions, could be a promising candidate for wound dressing therapeutic applications. [ABSTRACT FROM AUTHOR]

Although a variety of functional polyvinyl alcohol hydrogels (PVAHG) with attractive mechanical and electrochemical properties have been fabricated using traditional freeze‐thaw cycling, this approach is usually relatively complicated, time‐consuming and relies essentially on the use of PVA chains with a weight‐average molecular weight above 60000. Here a new strategy capable of assembling relatively low‐molecular‐weight (≈30000) polyvinyl alcohol (PVA) into highly crosslinked physical hydrogels is developed. By exploiting ammonium persulfate as a simple and versatile oxidant to simultaneously provide oxidizing and salting‐out effects to the polymeric building blocks, PVAHG with excellent and tailorable elasticity, conductivity and sensitivity can be achieved building on the strong intermolecular hydrogen bonding between the newly formed ─COOH and ─CHO terminations and the inclusion of abundant inorganic ions. The hydrogels cannot only act as effective wearable wireless sensors for detecting output resistance signals but also be further employed to construct a motion‐mapped self‐propelled robotic arm that is able to instantly and accurately map the motion of human bodies. This study may provide new insights into polymer chemistry, hydrogel sensing, and soft robotics. [ABSTRACT FROM AUTHOR]

In this research the synthesis of graphene oxide (GO) through the Hummers method, to obtain various percentage nanocomposite materials incorporating GO into polyvinyl alcohol (PVA) (2%GO/PVA, 3%GO/PVA, and 20%GO/PVA), and the detailed investigation of these composites’ morphological, structural, and optical characteristics using X-ray diffraction (XRD), Fourier-transform infrared (FTIR), Raman spectroscopy, and Scanning electron microscopy (SEM). The main goal of the presented work is to investigate how the physical properties change in the wide-range concentrations of the GO/PVA composite materials, as well as at different thermal annealing temperatures. From the XRD results, the space between the sheets is decreased by increasing the thermal annealing temperature. By the Halder-Wagner method, crystallite size and microstrain of the various percentages of GO/PVA were determined. The high microstrain and crystallite size belong to thermal annealed at 70°C of 3% GO/PVA (D = 8.50 nm/ε = 11%) and thermal annealed at 40°C of 20% GO/PVA (D = 13.70 nm/ε = 16 %). At room temperature and the highest annealing temperature, the microstrain value is minimal or equal to 0, because, its crystal structure is stable at low temperatures and it occurs as a result of relaxation due to rearrangement of the polymer chain at high temperatures. From Raman measurements, the ID/IG ratio for 2% and 3% GO/PVA composite materials increased with increasing temperature compared to the pristine GO. This indicates that the defect in the structure increases due to temperature. [ABSTRACT FROM AUTHOR]

We have modified the metal-assisted transfer technique to obtain large-area, few-layer flakes from transition metal dichalcogenide bulk crystals by introducing an initial stage—exfoliation of the bulk crystal onto an intermediate substrate, specifically a silicon wafer coated with polyvinyl alcohol. Following this, we thermally evaporate silver onto the sample and transfer the top layers of the crystal along with the silver layer to the target substrate. This technique allows the production of visually non-corrugated single- and few-layer flakes with high yield. A direct comparison of the micro-Raman and micro-photoluminescence spectra of flakes exfoliated using our method with the spectra of those exfoliated from the scotch tape reveals differences in their properties. We identify signatures of deformations in the flakes exfoliated from the intermediate substrate, indicating the presence of static friction between the substrate and the flake. Our findings, thus, suggest a useful method to induce intrinsic deformation in 2D materials. [ABSTRACT FROM AUTHOR]

Summary This study aims to develop a novel active food packaging material from hybrid micro‐nanofibrous mats fabricated from gelatin (G)–chitosan (Ch)–polyvinyl alcohol (PVA)–Origanum elongatum essential oil (EO), (G‐Ch‐PVA‐EO) through electro‐blowing. The fibrous mats were characterised to assess their morphologies, shelf life efficiency, antimicrobial and antioxidant properties, surface‐wetting, and thermal, chemical, and physical interactions, among other factors. Results showed that the antioxidant activity was improved with the addition of EO, this enhancement is potentially linked to its rich content of phenolic components; carvacrol and P‐cymene. In addition, G‐Ch‐PVA‐EO showed higher firmness measurements compared to the control samples. Herein, low microbial counts were noted for both mesophilic aerobic bacteria (3.76 log CFU g−1) and yeast/mould (3.91 log CFU g−1) even at day 20. To conclude, the G‐Ch‐PVA‐EO microfibrous mat exhibits great promise in preserving the freshness of tomatoes. [ABSTRACT FROM AUTHOR]

The escalating focus on environmental concerns and the swift advancement of eco‐friendly biodegradable batteries raises a pressing demand for enhanced material design in the battery field. The traditional polypropylene (PP) that is monopolistically utilized in the commercial LIBs is hard to recycle. In this work, we prepare a novel water degradable separators via the cross‐linking of polyvinyl alcohol (PVA) and dibasic acid (tartaric acid, TA). Through the integration of non‐solvent liquid‐phase separation, we successfully produced a thermally stable PVA‐TA membrane with tunable thickness and a high level of porosity. These specially engineered PVA‐TA separators were implemented in LiFePO4 (LFP)|separator|Li cells, resulting in superior multiplicative performance and achieving a capacity of 88 mAh g−1 under 5 C. Additionally, the straightforward small molecule cross‐linking technique significantly reduced the crystalline region of the polymer, thereby enhancing ionic conductivity. Notably, after cycling, the PVA‐TA separators can be easily dissolved in 95 °C hot water, enabling its reutilization for the production of new PVA‐TA separators. Therefore, this work introduces a novel concept to design green and sustainable separators for recyclable lithium batteries. [ABSTRACT FROM AUTHOR]

The crucial point of solar thermal utilization makes solar heat collector gathering much attention. In this study, imitating polar bears' fur structure, fluorescent materials are modified into a solar heat collector, and the photothermal conversion is evaluated to examine the influence of polyvinyl alcohol concentration, fluorescent luminescence type and fluorescence concentration. The test results indicate that fluorescent materials that has a greater Stokes shift show the greater photothermal effect. Moreover, when composed of a PVA concentration being 5.0% and a fluorescent concentration being 0.50%, the composites exhibit the maximal photothermal conversion temperature (99.4°C) that is 17.9% higher than that of the solar heat collectors without fluorescent materials. This study proposes creating solar heat collector with modified fluorescent materials, and the new perspective of which demonstrates that the composites have a great potential and application prospect in the solar photothermal field. [ABSTRACT FROM AUTHOR]

This paper presents the development of the blend polymer solid electrolyte films (BPSE) for potential applications in electrochemical devices. Two host polymers, polyvinyl alcohol (PVA) and polymethyl methacrylate (PMMA), along with the salt KI, are employed to create the solid polymer electrolytes (SPEs). The synthesis involves varying the weight percentage of salt within the SPEs to investigate its impact on the material properties. Conductivity measurements are conducted using AC impedance spectroscopy, unveiling the conductivity behavior of the BPSEs. Additionally, surface morphology is characterized using polarized optical microscopy (POM) at 10 pixel resolution, offering a detailed examination of the film's microstructure. This comprehensive study not only contributes to the understanding of the fundamental properties of BPSEs but also opens avenues for their utilization in various electrochemical applications. [ABSTRACT FROM AUTHOR]

Jugular paragangliomas are highly vascularized tumors that can grow in challenging neurovascular compartments and are particularly challenging to resect. There is still no consensus whether preoperative embolization should be employed to minimize intraoperative morbidity. A systematic review and meta-analysis was conducted by searching PubMed, Web of Science, and Embase databases for key terms including "embolization," "jugular paragangliomas," and "surgery." This review included 25 studies with 706 patients and 475 (67%) preoperative embolizations. Polyvinyl alcohol particles were the most common embolic agent (97.8% of all patients who underwent embolization). Complication rate of embolization was 1% (95% confidence interval [CI]: 0%, 2%). Preoperative embolization was significantly associated with less intraoperative estimated blood loss (mean difference of −7.92 dL [95% CI: −9.31 dL, −6.53 dL]), shorter operating room times (mean difference of −55.24 minutes [95% CI: −77.10 minutes, −33.39 minutes]), and less overall tumor recurrence (odds ratio = 0.23 [95% CI: 0.06, 0.91]) compared with resective surgery alone. Preoperative embolization had no impact on the development of postoperative new cranial nerve deficits not associated with embolization (odds ratio = 1.17 [95% CI: 0.47, 2.91]) and achievement of gross total resection (odds ratio = 1.92 [95% CI: 0.67, 5.53]). Preoperative embolization may provide surgical efficiency with faster surgical times and less bleeding and safety with diminished overall recurrence via safe embolization with minimal risks. These results must be considered taking into account the nonrandomness of studies. [ABSTRACT FROM AUTHOR]

A novel bimetallic Fe/Co-metal–organic framework (MOF) hydrogel-based wearable sweat sensor was developed. Morphological and structural analysis of the hydrogel shows uniformly sized spines and spindle-shaped particles of the Fe/Co-MOF, and it has a high surface area (132.306 m2 g−1) and porosity (0.059 cm3 g−1) as confirmed by Brunauer–Emmett–Teller (BET) studies. The integration of the bimetallic MOF into a polyvinyl alcohol/chitosan (PVA/CS)-mixed matrix resulted in a multiple network hydrogel. The optimisation study investigated the effects of different pH of the PBS electrolyte, scan rates, and accumulation time in voltammetry. The electrochemical methods such as cyclic voltammetry (CV), square wave voltammetry (SWV), and electrochemical impedance spectroscopy (EIS) provided information on the redox behaviour, electrochemical stability, and catalytic activity of the hydrogel. The sensor demonstrates a wide linear detection range from 0.05 µM to 100 mM, a superior sensitivity of 0.02 mA mM−1 cm−2, and a lower limit of detection of 0.01 µM. Active sites distributed over the hydrogel surface, specifically Fe2+ and Co2+ within the MOF structure, catalyse the oxidation of l-lactic acid, resulting in electron transfer and the formation of pyruvic acid. Notably, the fabricated sensor exhibits high selectivity, effectively discriminating against interfering species such as uric acid, ascorbic acid, glucose, urea, dopamine, NaCl, and CaCl2. Real-time analysis conducted in a simulated sweat sample via the standard addition method resulted in good recovery percentages of a minimum of 98%. The work presented here is a versatile and simple platform for point-of-care testing, especially for athletes and military personnel. [ABSTRACT FROM AUTHOR]

In this paper, the humidity-sensing characteristics of gelatin were compared with those of poly(vinyl alcohol) (PVA) at L-band (1 ~ 2 GHz) microwave frequencies. A capacitive microwave sensor based on a defected ground structure with a modified interdigital capacitor (DGS-MIDC) in a microstrip transmission line operating at 1.5 GHz without any coating was used. Gelatin is a natural polymer based on protein sourced from animal collagen, whereas PVA is a high-sensitivity hydrophilic polymer that is widely used for humidity sensors and has a good film-forming property. Two DGS-MIDC-based microwave sensors coated with type A gelatin and PVA, respectively, with a thickness of 0.02 mm were fabricated. The percent relative frequency shift (PRFS) and percent relative magnitude shift (PRMS) based on the changes in the resonant frequency and magnitude level of the transmission coefficient for the microwave sensor were used to compare the humidity-sensing characteristics. The relative humidity (RH) was varied from 50% to 80% with a step of 10% at a fixed temperature of around 25 °C using a low-reflective temperature and humidity chamber manufactured with Styrofoam. The experiment's results show that the capacitive humidity sensitivity of the gelatin-coated microwave sensor in terms of the PRFS and PRMS was higher compared to that of the PVA-coated one. In particular, the sensitivity of the gelatin-coated microwave sensor at a low RH from 50% to 60% was much greater compared to that of the PVA-coated one. In addition, the relative permittivity of the fabricated microwave sensors coated with PVA and gelatin was extracted by using the measured PRFS and the equation was derived by curve-fitting the simulated results. The change in the extracted relative permittivity for the gelatin-coated microwave sensor was larger than that of the PVA-coated one for varying the RH. [ABSTRACT FROM AUTHOR]

Ion−conducting hydrogels show significant potential in plant growth monitoring. Nevertheless, traditional ionic hydrogel sensors experience substantial internal creep and inadequate sensitivity, hindering precise plant growth monitoring. In this study, we developed a flexible hydrogel sensor composed of polyvinyl alcohol and acrylamide. The hydrogel sensor exhibits low creep and high sensitivity. Polyvinyl alcohol, acrylamide, and glycerol are crosslinked to create a robust interpenetrating double network structure. The strong interactions, such as van der Waals forces, between the networks minimize hydrogel creep under external stress, reducing the drift ratio by 50% and the drift rate by more than 60%. Additionally, sodium chloride and AgNWs enrich the hydrogel with conductive ions and pathways, enhancing the sensor's conductivity and demonstrating excellent response time (0.4 s) and recovery time (0.3 s). When used as a sensor for plant growth monitoring, the sensor exhibits sensitivity to small strains and stability for long−term monitoring. This sensor establishes a foundation for developing plant health monitoring systems utilizing renewable biomass materials. [ABSTRACT FROM AUTHOR]

Polyvinyl alcohol (PVA)-based hydrogels have attracted significant attention due to their excellent biocompatibility, tunable mechanical properties, and ability to form stable three-dimensional networks. This comprehensive review explores the recent advancements in PVA-based hydrogels, focusing on their unique properties, fabrication strategies, and multifunctional applications. Firstly, it discusses various facile synthesis techniques, including freeze/thaw cycles, chemical cross-linking, and enhancement strategies, which have led to enhanced mechanical strength, elasticity, and responsiveness to external stimuli. These improvements have expanded the applicability of PVA-based hydrogels in critical areas such as biomedical, environmental treatment, flexible electronics, civil engineering, as well as other emerging applications. Additionally, the integration of smart functionalities, such as self-healing capabilities and multi-responsiveness, is also examined. Despite progress, challenges remain, including optimizing mechanical stability under varying conditions and addressing potential toxicity of chemical cross-linkers. The review concludes by outlining future perspectives, emphasizing the potential of PVA-based hydrogels in emerging fields like regenerative medicine, environmental sustainability, and advanced manufacturing. It underscores the importance of interdisciplinary collaboration in realizing the full potential of these versatile materials to address pressing societal challenges. [ABSTRACT FROM AUTHOR]

Graphene nanoplatelets with high thermal diffusivity are being researched for their ability to improve the thermal characteristics of adsorbents. Similarly, ionic liquids with hydrophilic properties have shown promising sorption and thermal attributes. In this study, novel composite adsorbents are developed, comprising few-layered graphene nanoplatelets and specific ionic liquids (ethyl-methylimidazolium methanesulfonate (EMIMCH3SO3) and ethyl-methylimidazolium chloride (EMIMCl)), along with polyvinyl alcohol binder. The composites, known as GP-CL-30-CP and GP-CH3SO3-30-CP, each contain 30% ionic liquid content. The aim is to capitalise on the superior thermal properties of graphene nanoplatelets and the stability and solvation characteristics of ionic liquids to enhance water and cooling production in adsorption-based cooling and desalination processes, addressing challenges in the water–energy nexus. The findings revealed an improvement in the thermal diffusivity of the composites by 167%, which is 76 times higher than the baseline silica gel. There was an increase in water uptake from 0.3534 kg/kg for silica gel to 0.9648 kg/kg for the composites, representing a 174% enhancement in water sorption, and hence more freshwater water production. [ABSTRACT FROM AUTHOR]

A new polymer hyrogel dosimeter based on acrylic acid in polyvinyl alcohol hydrogel matrix was prepared to be used in radiation measurments for radiotherapy treatment. The hydrogel dosimeters were exposed to ionizing radiation using a medical linear accelerator. The hydrogel samples were irradiated at 6 MV beam energy, 600 cGy min−1 dose rate, and various doses up to 50 Gy. UV–VIS Spectrophotometry was used to readout the dose response of non-irradiated and irradiated hydrogel samples at absorbance of 630 nm. The results show the dose response increases strongly with increasing abosrbed doses, with a large linear dose range (2–30 Gy) and dose sensitivity of 0.013 Gy−1 s−1. Moreover, no significant variation in dose response was obseved when the gel samples are irridiated under different dose-rates as well as radiation beam energies. A noticeble change in the stability of the irradiated hydrogel samples was found within the first three days of irradiation, followed by a high post-irradiation stability, for the next 14 days. The non-irridiated samples were stable, up to 10 weeks. [ABSTRACT FROM AUTHOR]

During the production of UO2 core fuel elements for high-temperature gas-cooled reactors, a complex organic low-level radioactive wastewater (OLLRW) containing large amounts of tetrahydrofurfuryl alcohol (THFA), polyvinyl alcohol (PVA), and other organics is generated. So it's urgent to have a pretreatment method to efficiently degrade the large and small molecular organic matters. Therefore, the Fenton continuous oxidation method developed in this study cleverly utilizes the secondary enhanced oxidation of H2O2. Compared with the conventional advanced oxidation method, the degradation efficiency of organic matter in simulated wastewater by continuous Fenton oxidation can be doubled, reaching 99.5%. The chemical oxygen demand (COD) of real complex uranium-containing OLLRW was reduced from 18,480 to 979.0 mg L−1. After further oxidative degradation of organic compounds in simulated OLLRW, the COD of wastewater can be reduced to 88.9 mg L−1. This method can effectively mitigate the "toxic" effect of organic matter on adsorption process, thus providing a new idea for the pretreatment of complex OLLRW in high-temperature gas-cooled reactors. [ABSTRACT FROM AUTHOR]

The purpose of this work was to study the synthesis and characterization of an adhesive based on a glucose stabilized polyvinyl acetate homopolymer. Vinyl acetate monomer was stabilised onto liquid glucose using emulsion polymerization, and polymerization happened using potassium persulfate as an initiator. Here, the effects of adding liquid glucose as a stabiliser for adhesives were studied. Therefore, the current research examines whether liquid glucose, introduced at weight-based concentrations of 0.5% and 1.0%, is suitable as a colloid to produce PVAc adhesives for wood. By measuring viscosity, pH, contact angle, differential scanning calorimetry (DSC), and the pencil hardness test of films, the effect of adding liquid glucose as a colloid on physical, thermal, and mechanical properties was investigated. The shear strength of the PVAc homopolymers applied to wood using emulsions with varied liquid glucose concentrations was measured using a universal tensile machine. As the concentration of liquid glucose increased, the viscosity of the adhesives also considerably increased. Water resistance significantly rose when liquid glucose content increased, as was found by measuring the water contact angle. The use of liquid glucose increased the hardness of PVAc films, which was supported by the glass transition temperature. According to EN 204-205, the tensile shear strength with 1.0% of liquid glucose increased by 63.88% and 45.67%, respectively, over a pristine sample after 6 h of bonding in a dry environment and 24 h in a wet environment. The study's overall conclusion highlights the higher adhesion capability of PVAc emulsion-based adhesives stabilized by liquid glucose. [ABSTRACT FROM AUTHOR]

To overcome the two main obstacles of large‐scale application of superspreading material, self assembly is used to prepare superspreading polymer membrane (SPPM) in this work. An amphiphilic SPPM is prepared by capillary force‐driven self assembly using PP melt‐blown nonwovens and polyvinyl alcohol (PVA). The prepared SPPM has low preparation cost and stable performance since self assembly needs low energy consumption, and the production is thermodynamically stable. By using cryo‐electron microscopy, transmission electron microscopy, X‐ray photoelectron spectrum and scanning electron microscope with energy dispersive X‐ray spectroscopy. It is proved that PVA is successfully assembled on the fiber surface of PP melt‐blown nonwovens. The prepared SPPM has excellent spreading performance, the "spreading times" of both water and oil are less than 0.5 s. They showed much superior performance compared to traditional materials when applied in oil‐water separation, seawater desalination, and ion separation. This work will definitely promote the development of self assembly, superspreading materials, and related sciences. [ABSTRACT FROM AUTHOR]

Given the challenges encountered in injecting grout into micro-cracked rock masses, a modified ultrafine cementitious grout material (MUCG) was developed using ultrafine cement, polyvinyl alcohol (PVA) fibers, and a high-efficiency superplasticizer. To identify the optimal ratio of constituents for grouting these rock masses, extreme difference and multiple linear regression analyses were conducted based on test results of flowability and mechanical properties. A mix comprising 9% silica fume, 0.2% bentonite, 0.3% PVA fibers, 0.15% superplasticizer, and 2% setting accelerator was identified as the optimal mix. The microstructure characteristics of the optimal MUCG (MUCGop) grout cemented body were analyzed using XRD, FTIR, BET, and SEM. XRD and FTIR analyses indicated that a substantial amount of C-(A)S-H gel, CH, and AFt were formed within the first 3 days, highlighting the early strength characteristics of MUCGop. Over time, the content of C-A-H stabilized at 22%, the amount of CH decreased from 19% to 14%, whereas the amount of AFt increased to 15.9% by Day 28. Unexpectedly, CaCO3 content increased due to carbonation, reaching 37.3% by Day 28. BET and SEM analyses demonstrated that the specific surface area and porosity (most probable pore size) gradually decreased over time. At various ages, mesopores (cumulative pore diameter, median pore diameter) initially increased and then decreased. Micro-cracks appeared in the cemented body by Day 7, resulting in a slight decrease in strength (3.92%) from Day 3 to Day 7. The formation of well-developed needle-like AFt, C-(A)S-H gel, and small-volume plate-like CH contributed to uniform cementation and a denser structure. From Day 7 to Day 28, there was a slight increase in strength, by an amount of 10.66%. These findings have significant scientific implications for understanding the mechanisms of grouting reinforcement in micro-cracked rock masses. [ABSTRACT FROM AUTHOR]

A novel nickel-molybdenum carbide-graphite nanofiber composite is introduced as an electrocatalyst for ethanol electrooxidation. The proposed nanofibers have been prepared by calcinating electrospun nanofibers composed of nickel acetate tetrahydrate, molybdenum chloride, and polyvinyl alcohol. The calcination process was conducted at different temperatures (700, 850, and 1000°C) under a nitrogen gas atmosphere with a heating rate of 2.5 deg/min and a holding time of 5 h. Physicochemical characterizations have indicated that nickel acetate is entirely reduced to nickel metal during the sintering process, and molybdenum has bonded with carbon to produce molybdenum carbide. At the same time, the used polymer has been pyrolyzed to produce a carbon nanofiber matrix embedding formed inorganic nanoparticles. Electrochemical measurements concluded that molybdenum content and calcination temperature should be controlled to maximize the electrocatalytic activity of the proposed catalyst. Typically, the oxidation peak current density was 28.5, 28.8, 51.5, 128.3, 25.6, and 3 mA/cm2 for nanofibers prepared from an electrospun solution containing 0, 5, 10, 15, 25, and 35 wt% molybdenum carbide, respectively. Moreover, it was observed that increasing the calcination temperature distinctly improves the electrocatalytic activity. Kinetic studies have indicated that the reaction order is close to zero with a reaction temperature-dependent value. Moreover, it was detected that the electrooxidation reaction of ethanol over the proposed nanofiber composite follows the Arrhenius equation. The determined activation energy is 33 kJ/mol, which indicates good catalytic activity for the introduced nanofibers. Through the application of a set of visualization-based tools and the general linear model (GLM), the optimal conditions that generate the highest current density were identified. The computations unveiled that the optimal parameter settings are as follows: Mo content at 15 wt.%, methanol concentration of 1.55 M, and reaction temperature of 59°C. [ABSTRACT FROM AUTHOR]

Microneedles (MNs) are minimally invasive transdermal drug delivery systems capable of penetrating the stratum corneum to overcome the barrier properties. The primary objective of this research was to prepare dissolving microneedle patches (DMNP) loaded with quetiapine (QTP). DMNP were fabricated employing the solvent casting technique, utilizing various polymer feed ratios including polyvinyl alcohol (PVA), polyvinylpyrrolidone K30 (PVP-K30), and polylactide-co-glycolide (PLGA) polymers. The loaded DMNP with QTP underwent a comprehensive characterization process encompassing assessments for compatibility, thickness, insertion potential, morphology, thermal behavior, X-ray diffraction, ex-vivo permeation, skin irritation, and histopathological changes. FTIR studies confirmed the compatibility of QTP with the microneedle patch composites. The thickness of the drug-loaded DMNP ranged from 0.67 mm to 0.97 mm. These microneedles exhibited an impressive penetration depth of 480 μm, with over 80% of the needles maintaining their original shape after piercing Parafilm-M. SEM analysis of the optimized DMNP-2 revealed the formation of sharp-tipped and uniformly surfaced needles, measuring 570 μm in length. Remarkably, the microneedles did not elicit any signs of irritation upon application of the prepared DMNP. The DMNP-2 showcased an impressive cumulative ex-vivo permeation of QTP, reaching 17.82 µg/cm2/hr. Additionally, histopathological assessment of vital organs in rabbits attested to the safety profile of the formulated microneedle patches. In conclusion, the developed microneedle patch represents a promising strategy for enhancing the transdermal delivery of QTP. This innovative approach has the potential to increase patient compliance, offering a more efficient and patient-friendly method of administering QTP. [ABSTRACT FROM AUTHOR]

Air pollution containing microorganisms presents a significant risk to human health. It is crucial to create air filters that are highly efficient for air purification and conducive to human health. Hence, this work aims to develop a filter based on melt-blown polypropylene (PP) spray-coated with green-synthesized silver nanoparticles (AgNPs). A bio-reducing agent from extracted spent green tea (SGT) was used in the AgNPs synthesis. Polyvinyl alcohol cross-linked with citric acid was used as a binder in spray coating. Effects of silver nitrate (AgNO3) concentrations, viz. 50, 100, and 150 mM, were investigated on AgNP formation and properties of spray-coated PP filter. Based on the results, the spray-coated PP filter with synthesized AgNP at 100 mM AgNO3 (AgNPs-100) showed the highest inhibition zones of both Gram-positive and Gram-negative bacteria. The tensile strength of the spray-coated PP filter with AgNPs ranged from 1309–1478 kPa, which was higher than that of the neat PP filter. The particle filtration efficiency of the spray-coated PP filter with AgNPs-100 for various particle sizes was enhanced by 27.95–447.04% compared to the neat PP filter. Moreover, the particle filtration efficiency of the spray-coated filter with AgNPs-100 was higher than 97% for particles of 0.3 μm, including PM1.0 and PM2.5. Therefore, the proposed spray-coated PP filter had a high potential to be a promising disinfecting filter for biomedical and hygienic applications. [ABSTRACT FROM AUTHOR]

Drug contamination is one of the most dangerous categories of impurities, which can be mitigated by photocatalysis reaction. Despite the unignorable advantage of nanophotocatalyst, their separation from batch reaction is challenging. Herein, a developed equipment is presented based on immobilizing a nanocatalyst onto the surface of a non-soluble polymeric substrate to degrade high amounts of chloramphenicol and amitriptyline under UV radiation. At first, polyvinyl alcohol plates were prepared through cross-linking by C6H9NaO7 in the presence of C5H8O2 and then characterized according to the water uptake amount and measuring water contact angle. The nanocatalyst was prepared by mixing two separate core–shell suspensions of Fe3O4@SiO2 and WO3@TiO2; afterward, Fe3O4@SiO2–WO3@TiO2 was sprayed onto the surface of the plates. The materials were characterized by X-ray diffraction spectroscopy, FTIR analysis, scanning electron microscopy, energy dispersive X-ray spectrometry, elemental mapping analysis, thermogravimetric analysis, Brunauer−Emmett−Teller and diffuse reflectance spectroscopy. The degradation recovery was optimized with respect to pH, UV radiation time and nanocatalyst amount. The adsorption efficiency, degradation efficiency, reusability, reproducibility, durability, effect of interference ions, adsorption isotherm, adsorption kinetic, photocatalytic kinetic and degradation mechanism were studied and explained. Analytical greenness metric approach is reported. Four different water samples were successfully employed as real samples. [ABSTRACT FROM AUTHOR]

Medicinal plant of Senna alata (S. alata) extract incorporated into Polyvinyl alcohol (PVA) film was successfully synthesized through a solution casting technique. The surface morphology of PVA/S. alata film was characterized by FE-SEM, which revealed the smooth and homogenous surface of the film and indicated the dispersion of S. alata in the PVA matrix. PVA functional group of hydroxyl and principal component of S. alata leaves flavonoids and anthraquinones presented in PVA/S. alata film was confirmed by FTIR spectra. XRD pattern results showed the crystallinity nature of PVA/S. alata film. Thermal analysis (TGA/DTG) demonstrated that incorporating S. alata extract in the PVA matrix enhanced the film thermal stability. In-vitro scratch wound assay was studied for PVA/S. alata film. The maximum wound healing activity of 93% was attained at 24 h with interaction on the mouse fibroblast L929 cell line, and wound gap width was measured through Image J software. Therefore, the developed PVA/S. alata film shows significant potential as an effective wound dressing material. [ABSTRACT FROM AUTHOR]

This study illustrates the impact of different polymer types on the characteristics of Fe2O3. The manufacture of nanocomposites involved the use of polyethylene oxide (PEO), polyvinyl alcohol (PVA), and Poly (methyl methacrylate) (PMMA) polymers. Nanocomposites were synthesised by combining an aqueous solution of Ferric chloride with various polymers. The Fe2O3 nanocomposite, which was polymer-based, was synthesised using an in situ chemical approach to investigate the impact of different polymer types on its primary physical characteristics. The configuration of polymer-based Fe2O3 nanocomposites was investigated using diagnostic instruments such as SEM, EDX, and XRD. The modification of the polymer had a clearly noticeable and apparent effect on the optical and structural properties of the nanocomposites. The utilisation of SEM, XRD, and EDX techniques provided confirmation of the successful synthesis of nanocomposites based on Fe2O3. The UV–visible spectra were examined to investigate the optical characteristics of the fabricated samples. The bandgaps of the nanocomposites ranged from 1.9 to 2.25 eV. The Urbach energy was also determined for all of the processed samples. [ABSTRACT FROM AUTHOR]

To realize high-quality vascularized bone regeneration, we developed a multifunctional hydrogel (SHPP-ZB) by incorporating BMP-2@ZIF-8/PEG-NH 2 nanoparticles (NPs) into a sodium alginate/hydroxyapatite/polyvinyl alcohol hydrogel loaded with PDGF-BB, allowing for the sequential release of angiogenic and osteogenic growth factors (GFs) during bone repair. ZIF-8 served as a protective host for BMP-2 from degradation, ensuring high encapsulation efficiency and long-term bioactivity. The SHPP-ZB hydrogel exhibited enhanced mechanical strength and injectability, making it suitable for complex bone defects. It provided a swelling interface for tissue interlocking and the early release of Zn2+ and tannin acid (TA) to exert antioxidant and antibacterial effects, followed by the sequential release of angiogenic and osteogenic GFs to promote high-quality vascularized bone regeneration. In vitro experiments demonstrated the superior angiogenic and osteogenic properties of SHPP-ZB compared to other groups. In vivo experiments indicated that the sequential delivery of GFs via SHPP-ZB hydrogel could improve vascularized bone regeneration. Further, RNA sequencing analysis of regenerative bone tissue revealed that SHPP-ZB hydrogel promoted vascularized bone regeneration by regulating JUN, MAPK, Wnt, and calcium signaling pathways in vivo. This study presented a promising approach for efficient vascularized bone regeneration in large-scale bone defects. [Display omitted] • The BMP-2/ZIF-8/PEG-NH 2 NPs achieved long-term bioactivity and sustained release. • The in-situ forming hydrogel with uniform drug was suitable for complex bone defect. • The hydrogel with enhanced mechanics exhibited antioxidant and antibacterial effect. • The sequential PDGF-BB and BMP-2 release accelerated vascularized bone regeneration. • RNA sequencing analysis revealed the potential bone regeneration mechanism in vivo. [ABSTRACT FROM AUTHOR]

Biofilms in food processing environments pose a potential risk of contamination by pathogenic and spoilage microorganisms, and Yersinia enterocolitica, known for its wide temperature adaptation, is the third most common zoonotic pathogen in the European Union. This study investigates the inhibitory effects of protocatechuic acid (PCA) at sub-inhibitory concentrations on various stages of Y. enterocolitica biofilm formation. Core genes are identified through transcriptome data and weighted gene co-expression network analysis (WGCNA), and the potential binding sites are predicted using molecular docking. Additionally, polyvinyl alcohol (PVA) films containing PCA are prepared to assess their antibacterial and mechanical properties. PCA is found to inhibit biofilm formation by up to 50.5% without affecting bacterial growth, reducing flagella-mediated motility, hydrophobicity, cohesion, and extracellular polysaccharides (EPS) content, and inhibiting the production of acyl-homoserine lactones (AHLs). Transcriptome data reveal that PCA inhibits biofilm formation by suppressing the quorum sensing system and reducing the expression of genes such as CsrD, yenR, FlhD, and FlhC. The PVA-PCA antimicrobial film exhibits robust mechanical properties, effectively reducing total colonies in pork and slowing down the deterioration rate. This study enhances our understanding of PCA's inhibitory effects on Y. enterocolitica and suggests its potential application as a quorum-sensing inhibitor in antimicrobial films for the food industry. [ABSTRACT FROM AUTHOR]

The anammox reaction simultaneously utilizes ammonia and nitrite as substrates; however, high nitrite concentrations act as strong inhibitors of the reaction. In this study, inhibition by NO 2 − and free nitrous acid (FNA) was separately evaluated in continuous feeding tests using different biomass carriers. The influent NO 2 − concentration was increased under pH 7.6, where FNA is less likely to affect anammox activity. A continuous test using polyethylene glycol (PEG) gel carriers containing immobilized anammox bacteria showed that the inhibition ratio was 13% when the NO 2 −-N concentration in the reactor was 350 mg L−1 (FNA ≤0.06 mg L−1). The relationship between NO 2 − concentration in the reactor and inhibition ratio increased linearly. Evaluation of the inhibitory effect of FNA by increasing the influent NO 2 − concentration at pH 6.4, where FNA is easily formed, demonstrated that the relationship between FNA and inhibition ratio could be fitted to a sigmoid curve, and the 50% inhibitory concentration (IC 50) of FNA was 0.88 mg L−1. A similar test performed using polyvinyl alcohol carriers containing anammox bacteria on their surface showed the same trend as the PEG gel carriers, with the IC 50 for FNA at 0.70 mg L−1. These results indicate that the inhibitory effect of FNA on anammox activity was greater than that of NO 2 −. The evaluation of these two factors helped identify important operational indicators of the stable application of anammox processes. • Inhibition by NO 2 − and free nitrous acid (FNA) was separately evaluated. • The inhibition ratio of 13% was observed under the NO 2 −-N of 350 mg L−1 at pH 7.6. • The relationship between NO 2 − concentration and inhibition ratio increased linearly. • The relationship between FNA and inhibition ratio could be fitted to a sigmoid curve. • The 50% inhibitory concentration of FNA was 0.88 mg L−1. [ABSTRACT FROM AUTHOR]

The release of antibiotics or anions by traditional bacteriostatic agents led to the development of bacterial drug resistance and environmental pollution. Ionic liquids (ILs) have become important choices for antibacterial agents because of their excellent physical, chemical and biological properties. In this paper, the bioactivities of 1-vinyl-3-butylimidazolium chloride ([VBIM]Cl, IL) and poly (1-vinyl-3-butylimidazolium chloride) (P[VBIM]Cl, PIL) were evaluated, and the potential antibacterial material was used to synthesize hydrogels. Using the colony formation assay and the Oxford cup method, antibacterial effect of IL and PIL were tested. Cell-Counting-Kit-8 (CCK-8) experiments were used to study the IC50 (half maximal inhibitory concentration) values of IL and showed 1.47 mg/mL, 0.35 mg/mL and 0.33 mg/mL at 24 h, 48 h and 72 h, respectively. The IC50 value of PIL were 12.15 μg/mL, 12.06 μg/mL and 11.76 μg/mL at 24 h, 48 h and 72 h, respectively. The PIL is further crosslinked with polyvinyl alcohol (PVA) to form a novel hydrogel through freeze-thaw cycles. The newly fabricated hydrogel exhibited a high water content, excellent water absorption properties and outstanding mechanical performance. Using the colony formation assay and the inhibition zone assay, the hydrogels exhibited favorable antibacterial effects (against E.coli and S.aureus) such that nearly 100% of the bacteria were killed in liquid medium while cultivating with H4 (synthesized by 0.5 g PIL and 1g PVA). In addition, the cytotoxicity of PIL was significantly reduced through hydrogen bond crosslinking. H4 showed the highest antibacterial activity and a good biocompatibility. The results indicated that the PVA&PIL hydrogels had great potential for wound dressing. [ABSTRACT FROM AUTHOR]