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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]

We introduce a method utilizing single laser-generated cavitation bubbles to stimulate cellular mechanotransduction in dermal fibroblasts embedded within 3D hydrogels. We demonstrate that fibroblasts embedded in either amorphous or fibrillar hydrogels engage in Ca2+ signaling following exposure to an impulsive mechanical stimulus provided by a single 250 µm diameter laser-generated cavitation bubble. We find that the spatial extent of the cellular signaling is larger for cells embedded within a fibrous collagen hydrogel as compared to those embedded within an amorphous polyvinyl alcohol polymer (SLO-PVA) hydrogel. Additionally, for fibroblasts embedded in collagen, we find an increased range of cellular mechanosensitivity for cells that are polarized relative to the radial axis as compared to the circumferential axis. By contrast, fibroblasts embedded within SLO-PVA did not display orientation-dependent mechanosensitivity. Fibroblasts embedded in hydrogels and cultured in calcium-free media did not show cavitation-induced mechanotransduction; implicating calcium signaling based on transmembrane Ca2+ transport. This study demonstrates the utility of single laser-generated cavitation bubbles to provide local non-invasive impulsive mechanical stimuli within 3D hydrogel tissue models with concurrent imaging using optical microscopy. STATEMENT OF SIGNIFICANCE: Currently, there are limited methods for the non-invasive real-time assessment of cellular sensitivity to mechanical stimuli within 3D tissue scaffolds. We describe an original approach that utilizes a pulsed laser microbeam within a standard laser scanning microscope system to generate single cavitation bubbles to provide impulsive mechanostimulation to cells within 3D fibrillar and amorphous hydrogels. Using this technique, we measure the cellular mechanosensitivity of primary human dermal fibroblasts embedded in amorphous and fibrillar hydrogels, thereby providing a useful method to examine cellular mechanotransduction in 3D biomaterials. Moreover, the implementation of our method within a standard optical microscope makes it suitable for broad adoption by cellular mechanotransduction researchers and opens the possibility of high-throughput evaluation of biomaterials with respect to cellular mechanosignaling.

A series of polyaniline (PANI) nanofibers were prepared as conductive fillers. A polyvinyl alcohol (PVA)/agarose (AG) double network hydrogel was used as a flexible substrate. A PANI/PVA/AG conductive hydrogel was prepared via in situ polymerization of polyaniline nanofibers in a PVA/AG double network hydrogel. The electrochemical performance of the PANI/PVA/AG hydrogel electrode material was linked to the fiber morphology of polyaniline. The doping of polyaniline with 0.020 mol L−1 citric acid demonstrated superior fiber morphology compared to doping with other citric acid concentrations, achieving fiber ratios of 80%. The specific capacitance of the PANI/PVA/AG hydrogel electrode materials doped with 0.020 mol L−1 citric acid was 285 mF cm−2, while the conductivity was 7.1 S m−1. The doping of polyaniline with 0.5 mol L−1 hydrochloric acid demonstrated superior fiber morphology compared to doping with other hydrochloric acid concentrations, achieving fiber ratios of 65%. The specific capacitance of PANI/PVA/AG hydrogel electrode materials doped with 0.5 mol L−1 hydrochloric acid was 249 mF cm−2, while their conductivity was 7.6 S m−1. After 500 cycles of charge–discharge, the specific capacitance retention of the material was 73%. Photosensitivity tests indicated that the hydrogel exhibited high sensitivity to shorter wavelengths of blue light (460 nm) and ultraviolet light (380 nm). The hydrogel sensor possessed high sensitivity to strain in the range of 0–120%. Gauge factors (GF) of the hydrogel strain sensor were 1.280, 2.141, 1.907, and 1.261 for strain ranges of 0–30%, 30–60%, 60–90%, and 90–120%, respectively. Cyclic strain tensile tests indicated that the relative resistance change rate (ΔR/R0) of the hydrogel sensor demonstrated a certain degree of repeatability and stability within the range of 0–100%. Thus, the hydrogel sensor is reliable and stable in the signal transmission process of detecting human movements as a flexible strain sensor. These results suggest that the PANI/PVA/AG conductive hydrogel is a multifunctional composite with good electrochemical storage performance, photosensitivity, and strain sensitivity that can be used in applications such as supercapacitors, flexible sensors and electronic wearable devices. [ABSTRACT FROM AUTHOR]

Binders used in binder jetting often pose health and environmental risks during processing and post processing operations. The print-heads which are used to deposit binder selectively on the feedstock are prone to clogging, despite the trend of print-heads being highly customised to suit different kinds of binders. These factors often hide the advantages of binder jetting as an additive manufacturing process, especially its scalability and its faster printing rates in comparison to powder bed fusion methods. The work presented here takes a step back and focuses on the development of an aqueous, polyvinyl alcohol (PVA)-based liquid binder that is easy to manufacture and store, safe to handle, and can be reliably jetted to print parts. The feedstock considered was Inconel 718, a nickel-based super alloy which can be effectively processed by binder jetting without niobium segregation. PVA was added to the Inconel 718 powder in dry, granular form to manufacture a modified feedstock. The study also investigated the role of molecular weight of the PVA used, sintering environments and post-processing methods like hot isostatic pressing (HIP) on process responses like part densification, tensile strength, and hardness. Three different types of PVA were chosen which had molecular weights 10,000 g/mol (low molecular weight or LMW), 26,000 g/mol (medium molecular weight or MMW), and 84,000 g/mol (high molecular weight or HMW). The compatibility of the liquid, aqueous PVA-based binders with virgin Inconel 718 was examined by measuring the contact angle. The liquid, aqueous binder having MMW PVA reported better wetting with the Inconel 718 powder with a wetting angle of 26.6 which was lower than the wetting angle of 42.4°, seen in case of a commercial resin-based binder. The green strength reported by the MMW PVA liquid binder was 220 kPa which was higher than the other two PVA-based liquid binders. Green parts, upon successful printing, were sintered at 1260 °C. It was observed that a part printed using MMW PVA had a densification of 96.16% when sintered in 99.98% by volume argon gas, which increased to 98.96% after undergoing HIP. The same part reported a densification of 88.69% when sintered in a 95% by volume N2 and 5% by volume H2 gaseous environment, which was later attributed to the uptake of nitrogen by the chromium present in Inconel 718, which prevented necking between particles. Tensile specimens printed using MMW PVA, sintered in a 99.98% argon environment, showed the highest ultimate tensile strength of 220 MPa, which increased to 1010 MPa after the HIP process, which can be compared to commercially available Inconel 718. [ABSTRACT FROM AUTHOR]

Janus particles are a class of materials that exhibit both surface morphology and chemical properties with asymmetry. However, at present, precise control over the structure and composition of Janus particles still faces numerous challenges. Conventional seed emulsion polymerization methods require heating to induce phase separation after seed swelling, leading to extended reaction periods. In light of this, we propose a novel photo-induced seed swelling polymerization approach. This method employs non-crosslinked polyglycerol methacrylate (poly(GMA)) as seed particles, utilizing 4-vinylpyridine (4-VP) as the functional monomer and divinylbenzene (DVB) as the cross-linker. The aqueous phase consists of polyvinyl alcohol (PVA) and sodium dodecyl sulfate (SDS), with 2,2-dimethoxy-2-phenylacetophenone (DMPA) as the photo-initiator. By adjusting parameters such as seed quantity, type of porogen, and porogen volume ratio, diverse morphologies including octopus-like, jellyfish-like, snowman-like, and half raspberry-like Janus particles are successfully synthesized. Subsequently, Janus carbon particles are obtained through calcination and employed as anode materials in lithium-ion batteries. The electrochemical performance of Janus carbon particles is assessed using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), rate capability tests, constant current charge–discharge measurements, and cycling performance evaluation. These tests indicate the excellent electrochemical properties of the material. Our research provides a valuable strategy for creating Janus carbon particles with controlled morphologies. [ABSTRACT FROM AUTHOR]

Mn4+-activated luminescent materials exhibit high color purity red light emission, but their limited water resistance hinders practical applications. In this study, citric and oxalic acids are innovatively employed for surface modification, resulting in luminescent materials with enhanced water resistance while preserving their luminescent intensity. This enhancement provides a prerequisite for their application in anti-counterfeiting films and aqueous fluorescent inks. Furthermore, the potential for optical information storage is successfully demonstrated by utilizing the photochromic fluorescent properties of polyvinyl alcohol films deposited on oxalic acid-modified K 2 SiF 6 :Mn4+. Exploiting the 3 ms day time difference between equivalently and non-equivalently doped Mn4+ fluoride, a millisecond information encryption mode is proposed by combining oxalic acid-modified K 2 SiF 6 :Mn4+ (long decay time, τ = 8.99 ms) and K 3 AlF 6 :Mn4+ (short decay time, τ = 5.31 ms). This mode can be effectively decoded using digital cameras and editing software, achieving high-level anti-counterfeiting capabilities. This work advances the application of highly efficient Mn4+-activated red phosphors in the realm of information security. [ABSTRACT FROM AUTHOR]

Daytime radiative cooling material provides a low‐energy way of cooling because it can reflect sunlight and radiate heat without consuming any energy. However, there are still great difficulties in manufacturing low‐cost, high‐efficiency, sustainable, and biodegradable daytime radiative cooling materials. In this paper, poly (vinyl alcohol)/boron nitride (PVA/BN) composite aerogels were prepared by freeze‐drying technology. By adjusting the PVA concentration and BN content, the aerogel can achieve high sunlight reflectivity (96%), high mid‐infrared emissivity (96%) and good thermal insulation performance. Therefore, the temperature of the aerogel can be reduced to 12.5°C lower than the ambient temperature at night, and 5.5°C lower than the ambient temperature under the direct sunlight of 900 W/m2. This aerogel opens an environmentally sustainable pathway for radiative cooling applications. [ABSTRACT FROM AUTHOR]

A hydrogel that is expected as a biomedical load‐bearing material remains a substantial challenge. In this work, a multi‐solvent‐induced gradient aggregation state strategy is developed to construct lignin‐based supramolecular hydrogels that feature superstrong, tough, stretchable, and fatigue‐resistant properties. The multi‐solvent high‐temperature annealing induces the gradient crystallization of polyvinyl alcohol and the self‐assembly of lignin. The interior strong hydrogen‐binding and the external weak non‐covalent‐binding forms a gradient aggregation state microstructure and compact macrostructure, where lignin acts as an interfacial molecular bridge. By sharing interconnection points to collaboratively dissipate energy, the developed hydrogels demonstrate high modulus (74.4 MPa), toughness (90 MJ m−3), tear (34,000 J m−2), tensile (24.8 MPa), and compressive strength (60 MPa). Moreover, such lignin‐based supramolecular hydrogels also exhibit extraordinary fatigue resistance, biocompatibility, and reactive oxygen species scavenging activity. This gradient non‐covalent conjoined‐network caused by multi‐solvent high‐temperature annealing provides a new design strategy and potential for developing biomaterials that mimic biomedical load‐bearing materials (e.g., natural tendons and ligaments). [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, chitosan (C)‐polyvinyl alcohol (P) edible film containing bio‐fabricated nanosilver particles (nAg) (as antimicrobial agent) and beetroot peel extract (BRPE) (as antioxidant agent and pH indicator) was used as spoilage indicator in cold‐stored rainbow trout fillets. DPPH (2,2‐diphenyl‐1‐picrylhydrazyl) radical scavenging activity (43.02%), reducing power (2.87), and total phenolic content (360.50 mg GAE/g) of ethanolic BRPE were higher than aqueous extract. Silver nanoparticles were biosynthesized using silver nitrate reduction by chitosan, confirmed by UV–Visible spectroscopy, optical and scanning electron microscope images, and X‐ray diffraction analysis. The highest tensile strength (4.20 MPa) and elongation at break (118%) belonged to the CP‐BRPE film, and the lowest water vapor permeability (2.45 10−5 g/s/m/P) was related to the CP‐nAg film. Also, the lowest total viable count (6.17 log CFU/g), psychrotrophic bacteria (6.27 log CFU/g), Enterobacteriaceae (4.9 log CFU/g), pH (5.66), total volatile basic‐nitrogen (TVB‐N) (22.1 mg/100 g of fish), and thiobarbituric acid reactive substances (TBARS) (0.705 mg MDA/kg of fish) values of the packaged trout fillets were significantly (p ≤ 0.05) observed in CP‐BRPE‐gnAg treatment among the other treatments at the end of the storage period, and CP‐gnAg, CP‐BRPE, and CP treatments were in the next ranks, respectively. Colorimetric analysis of the used films showed that the films containing BRPE depicted color spectra of red to yellow at the same time as the spoilage symptoms initiated in the packaged fillets. It is concluded that BRPE not only increased the preservative effects of chitosan‐polyvinyl alcohol film containing green silver nanoparticles but also can be considered as a natural cost‐effective spoilage indicator of the rainbow trout fillets during cold storage time. [ABSTRACT FROM AUTHOR]

Hydroxypropyl methylcellulose (HPMC) incorporated bio-composite films (unplasticized and plasticized) were prepared from pregelatinized maize starch/polyvinyl alcohol (PMS/PVA) blends by solution casting method. 10% boric acid (BA) was used as crosslinker. The physico-mechanical properties (tensile strength (TS), elongation at break (%EB), water solubility and moisture uptake) of the bio-composite films were studied. The thermo-chemical stability of the biofilms was studied by FT-IR, TGA and DSC analysis. TS, %EB, water solubility and moisture absorbency of 10% HPMC containing unplasticized films were found 38.1 MPa, 8.5%, 61% and 32.3%, respectively, however, the films were hard and brittle. On the contrary, TS, %EB, water solubility and moisture absorbency of 10% HPMC plasticized films were found 19.2 MPa, 28.5%, 62.2% and 57.3%. The biofilms exhibited relatively low water solubility and moisture uptake compared to higher HPMC containing composite. The thermo-chemical analysis revealed that the HPMC incorporated plasticized film was more thermally stable compared to pure PMS, PVA, HPMC and other bio composite films due to strong hydrogen bonding interaction with BA. The biodegradability of HPMC incorporated plasticized films was confirmed by soil burial test (anaerobic condition, RH 98%, 3 months). Therefore, the plasticized biofilm would be considered an alternative approach for biocompatible packaging material. [ABSTRACT FROM AUTHOR]

As one of the world's most fragile and sensitive ecological regions, Xizang risks significant environmental damage from using traditional materials, including cement and lime, to improve and reinforce loose accumulated sandy soil slopes. To address this issue, this study utilized a low-concentration biodegradable polyvinyl alcohol (PVA) solution combined with sisal fibers (SFs) to stabilize loose accumulated sand in southeastern Xizang. A series of physical, mechanical, and microscopic analyses was conducted to evaluate the properties of the treated sand. The results indicated the following. 1) The stress-strain curves of the improved samples exhibited an elastic-plastic relationship. Failure was observed in two stages. At a strain of 3% or less, the samples demonstrated elastic deformation with a linear increase in stress, whereas the deviator stress increased rapidly and linearly with an increase in axial strain. Once the strain exceeded 3%, the deformation became plastic with a nonlinear increase in the stress-strain relationship, and the growth rate of the deviator stress gradually decreased and leveled off. 2) Under varying confining pressure conditions, the relationship curve between the maximum (σ1-σ3)max∼σ3 for both untreated loose accumulated sandy soil and soil improved with the PVA solution, and the sisal fiber was approximately linear. 3) The SFs created a skeletal-like network that encased the soil particles, and the hydroxyl functional groups in the PVA molecules bonded with both the soil particles and the fiber surface, thereby enhancing the interfacial properties. This interaction resulted in a tighter connection between the soil particles and SFs, which improved the stability of the structure. 4) The incorporation of a PVA solution and SFs significantly enhanced the mechanical strength and deformation resistance of the loose accumulated sandy soil. The optimal ratio for the improved soil was SP = 3% and SL = 15 mm, which increased the cohesion from 24.54 kPa in untreated loose accumulated sandy soil to 196.03 kPa. These findings could be applied in engineering practices to improve and reinforce loose accumulated sandy soil slopes in southeastern Xizang and provide a theoretical basis for such applications. [ABSTRACT FROM AUTHOR]

Diabetic wounds pose a challenge to healing due to increased bacterial susceptibility and poor vascularization. Effective healing requires simultaneous bacterial and biofilm elimination and angiogenesis stimulation. In this study, we incorporated polyaniline (PANI) and S-Nitrosoglutathione (GSNO) into a polyvinyl alcohol, chitosan, and hydroxypropyltrimethyl ammonium chloride chitosan (PVA/CS/HTCC) matrix, creating a versatile wound dressing membrane through electrospinning. The dressing combines the advantages of photothermal antibacterial therapy and nitric oxide gas therapy, exhibiting enduring and effective bactericidal activity and biofilm disruption against methicillin-sensitive Staphylococcus aureus, methicillin-resistant Staphylococcus aureus, and Escherichia coli. Furthermore, the membrane's PTT effect and NO release exhibit significant synergistic activation, enabling a nanodetonator-like burst release of NO through NIR irradiation to disintegrate biofilms. Importantly, the nanofiber sustained a uniform release of nitric oxide, thereby catalyzing angiogenesis and advancing cellular migration. Ultimately, the employment of this membrane dressing culminated in the efficacious amelioration of diabetic-infected wounds in Sprague–Dawley rats, achieving wound closure within a concise duration of 14 days. Upon applying NIR irradiation to the PVA-CS-HTCC-PANI-GSNO nanofiber membrane, it swiftly eradicates bacteria and biofilm within 5 min, enhancing its inherent antibacterial and anti-biofilm properties through the powerful synergistic action of PTT and NO therapy. It also promotes angiogenesis, exhibits excellent biocompatibility, and is easy to use, highlighting its potential in treating diabetic wounds. [ABSTRACT FROM AUTHOR]

In this study, guest carriers, composed of magnetic‐directed hydrogel particles with near‐infrared (NIR)‐light‐triggered guest‐release properties, are prepared via the one‐pot method. The gel particles contain photostable NIR‐responsive polypyrrole nanoparticles with temperature‐sensitive poly(N‐isopropyl acrylamide), the combination of which can induce the accelerated release of encapsulated drugs by 337% upon 5 minutes of NIR light irradiation based on the release profile of NRMG‐1 at 10–15 min. Additionally, with magnetic iron oxide particles crosslinking the polyvinyl alcohol frames, these gel particles can form a physical barrier that decreases the release rate by 20% under an external magnetic field over 24 h. The magnetic iron oxide particles also enable the gel particles to reach their target destination without extra drug losses. [ABSTRACT FROM AUTHOR]

Objectives: In the present study, blends of polyvinyl alcohol (PVA), starch (SH), nanohydroxyapatite (Nano-HA), and reduced graphene oxide (r-GO) were used to fabricate an electrospun nano scaffold (ENS), via electrospinning for their potential application in oral and maxillofacial bone soft and hard tissue regeneration. Materials and methods: The scaffold was characterized for its physicochemical and mechanical properties. An invitro study was carried out using human osteoblast MG-63 bone cells. Surface characterization, particularly the analysis of calcium content, was performed before and after immersion in the simulated body fluid (SBF). Additionally, the impact of surface treatment on antimicrobial activity was investigated. Results: The results demonstrated that the tensile strength (18.12 ± 0.14 MPa), elongation at break (19.23 ± 0.11%), and flexing index (20.15 ± 0.13%) of the ENS were outstanding, indicating promising performance. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assays demonstrated the biocompatible nature of the ENS. The bioactivity test result of ENS showed excellent deposition of bone apatite crystals. The ENS exhibited antimicrobial properties against E. coli (3.41 ± 0.03 mm) and S. aureus (3.12 ± 0.08 mm). Conclusions: The ENS, possessing the desired properties, has the potential to be tested in large animals for oral and maxillofacial bone and soft tissue regeneration after obtaining the necessary approvals. The developed ENS offers a promising solution for bone tissue regeneration in the oral and maxillofacial region. [ABSTRACT FROM AUTHOR]

Ti-6Al-4V metal is widely used as an implantable material due to its biocompatibility and corrosion resistance; however, it has low bioactive properties. The formation of nanotubes and a hydroxyapatite-polyvinyl alcohol-collagen composite coating on Ti-6Al-4V metal aims to enhance its biocompatibility and bioactivity. The nanotube oxide layer Ti-6Al-4V was formed by the anodization method. The composite’s infrared spectrum showed characteristic absorption bands from Hydroxyapatite (HAp), polyvinyl alcohol, and collagen. The composite-coated Ti-6Al-4V metal, both non-nanotube, and nanotube, showed a typical diffraction pattern of HAp and titanium element. The electron microscope image showed the uniform granular form of HAp. The corrosion test results showed that composite-coated nanotube Ti-6Al-4V metal could not improve corrosion resistance. It is also relevant to the in vitro test in a lactate ringer solution that showed the higher Ca2+ ion of nanotube Ti-6Al-4V metal than that of non-nanotube Ti-6Al-4V metal. [ABSTRACT FROM AUTHOR]

One of the main goals of contemporary biotechnology has been the development of novel immobilized enzyme formulations. In the present study, the industrially important β‐galactosidase was trapped in a polyvinyl alcohol (PVA) gel to immobilize it. The optimization of immobilization method and characterization of the immobilized enzyme were studied. The results were compared with free enzymes. The results indicate that the optimal temperature range for the enzyme to be at following immobilization is between 40°C and 50°C. At pH 7, the optimal pH, the activity increased, the Vmax value increased from 1.936 to 2.495 U mg‒1, and the Km value decreased from 4.861 to 0.982 mM. Depending on how stable the immobilized enzyme when stored, β‐galactosidases immobilized on PVA gels showed 52.87% activity at the end of the seventh week and 58.86% activity at the end of the fifth week. Their initial activity subsided after three reuses. The final result was 66%. Therefore, one may argue that it increases the catalytic effect of the enzyme. As a result, it has been found that immobilized β‐galactosidase has more potent enzymatic properties than free β‐galactosidase, which may make it more advantageous for industrial processes. Further studies could delve deeper into the mechanistic aspects of the immobilization process in an effort to improve optimization and tailor the immobilized enzyme to specific industrial needs. [ABSTRACT FROM AUTHOR]

In this study, a novel biodegradable polymer electrolyte membrane with reduced fuel crossover, high selectivity, and high conductivity compared with Nafion 117 membrane in direct ethanol fuel cells (DEFCs) has been reported. Herein, polyvinyl alcohol/epoxidized natural rubber (PVA/ENR) blend membranes were synthesized via a simple solution casting method and applied in DEFCs. The structural and physicochemical features of the PVA/ENR blend membranes were examined using FESEM, FTIR, XRD, water absorption, ethanol uptake, swelling ratio and oxidative stability. ENR enhances the chemical, structural, and mechanical characteristics of PVA, making it a valuable material in fuel cell applications. The incorporation of ENR into the PVA matrix results in a compact morphology, excessive multifunctional groups, low fuel crossover, and high selectivity. The optimum membrane thickness achieves the highest selectivity, reaching up to 12.32 × 104 S s cm−3 at 30°C. Additionally, the maximum power density achieved is 19.52 mW cm−2, surpassing that of the Nafion membrane, which is only 14.55 mW cm−2 at 90°C. Furthermore, this biodegradable membrane can sustain operation for 1000 h at 90°C, owing to its ability to maintain hydration for an extended period. This study represents the first attempt to combine PVA and ENR in fuel cells. [ABSTRACT FROM AUTHOR]

The present study aims to improve the mechanical strength of hydrogels via a simplified method, involving the creation of a nanocomposite hydrogel using polyvinyl alcohol (PVA) incorporated with un‐modified multiwalled carbon nanotubes (um‐MWCNTs). Departing from conventional freezing–thawing cycles, our research employs a facile approach, in which high‐shear mixing along with solvent exchange with deionized water was utilized. Morphological analysis unveiled a compact and dense microstructure within the nanocomposite hydrogel in correlation with MWCNT concentration. Attenuated total reflection‐Fourier transform infrared spectroscopy (ATR‐FTIR) elucidated the chemical structure of PVA/um‐MWCNTs hydrogel nanocomposite. Rheological studies on the viscoelastic properties indicated the formation of more "solid‐like" structure in the developed hydrogel nanocomposite. Broadband dielectric spectroscopy revealed alterations in dielectric properties of the fabricated PVA/um‐MWCNTs hydrogel nanocomposite corresponding to MWCNTs content in the PVA matrix. This comprehensive investigation highlights the impact of minimal MWCNTs concentration on the rheology, mechanical, and dielectric properties of developed PVA/um‐MWCNTs hydrogel nanocomposite. [ABSTRACT FROM AUTHOR]

Highly sensitive strain sensors have been widely used in human motion monitoring, medical treatment, soft robots, and human–computer interaction, and the recycling of functional materials is in a huge demand for eco‐friendly and sustainable electronics. However, the manufacturing of recyclable strain sensors still remains challenging. Here, a semi‐wrapped structure based on silver nanowires and polyvinyl alcohol is proposed to realize a recyclable and stable strain sensor. It has shown excellent sensitivity, fast response, high stretchability and good environmental stability, and is successfully applied for human motion monitoring. In addition, a simple strategy is developed to effectively recycle silver nanowires in an eco‐friendly manner. The recyclable and stable strain sensor demonstrates potential applications in wearable and stretchable electronics, and the recycling strategy can be extended to other noble metal nanomaterials. [ABSTRACT FROM AUTHOR]

Photochromic inks have shown disadvantages, such as poor durability and high cost. Self-healable hydrogels have shown photostability and durability. Herein, a viologen-based covalent polymer was printed onto a paper surface toward the development of a multi-stimuli responsive chromogenic sheet with thermochromic, photochromic, and vapochromic properties. Viologen polymer was created by polymerizing a dialdehyde-based viologen with a hydroxyl-bearing dihydrazide in an acidic aqueous medium. The viologen polymer was well immobilized as a colorimetric agent into a polyvinyl alcohol (PVA)/tricarboxy cellulose (TCC)-based self-healable hydrogel. The viologen/hydrogel nanocomposite films were applied onto a paper surface. The coloration measurements showed that when exposed to ultraviolet light, the orange layer printed on the paper surface switched to green. The photochromic film was used to develop anti-counterfeiting prints using the organic hydrogel composed of a PVA/TCC composite and a viologen polymer. Reversible photochromism with strong photostability was observed when the printed papers were exposed to UV irradiation. A detection limit was monitored in the range of 0.5–300 ppm for NH3(aq). The exposure to heat (70 °C) was found to reversibly initiate a colorimetric change. [ABSTRACT FROM AUTHOR]

Poly(vinyl alcohol) (PVA)-based films have drawn significant attention owing to their potential applications in various industries. The application of wax to PVA films enhanced their resistance to dissolution and water infiltration. Nevertheless, waxed PVA films often exhibit inadequate mechanical properties owing to crack formation. In this study, we evaluated the impact of glycerol as a plasticizer in varying concentrations of Carnauba wax (CW). The addition of glycerol to the PVA/CW blend led to enhanced mechanical properties compared to the blend without glycerol. The functional group and morphology of the blends confirm glycerol compatibility with PVA/CW films. Glycerol was fully dispersed to form a consistent polymer matrix and equally improved the film's contact angle. Furthermore, the thermal property from differential scanning calorimetry and thermogravimetric analysis highlights the plasticizing effect of glycerol in PVA/CW films, potentially broadening their use in food packaging and wrapping applications. [ABSTRACT FROM AUTHOR]

Aerogels have gained increasing attention due to their unique properties since their introduction in 1932. Silica aerogel, one of the earliest and most advanced types, is known for its high transparency and excellent thermal insulation. However, its internal pearl-like structure makes it extremely brittle, which limits its practical applications. To address this, through multiple refinements in formulation and production techniques, we developed a novel Polyvinyl Alcohol (PVA) aerogel using an innovative one-step standing method. This method significantly reduces the gelling time compared to the freeze–thaw method and eliminates the need for refrigeration, making it a more environmentally friendly and sustainable process. The resulting one-step standing PVA aerogel features a hierarchical porous structure, remarkable transparency, improved strength, and enhanced thermal insulation. Mechanical tests demonstrated that the PVA aerogel produced by the one-step standing method exhibited a significantly higher Young's modulus of 4.2596 MPa, surpassing that of silica, copper nanowire (Cu NM), and graphene aerogels. Additional tests, including transmittance and thermal analysis, further confirmed that the one-step standing PVA aerogel excels in both transparency and thermal insulation. This combination of improved mechanical performance and light transmission opens novel potential applications, such as drug delivery systems, where the aerogel's pore structure can store drugs while maintaining strength and transparency. [ABSTRACT FROM AUTHOR]

This investigation examined the potential antibacterial and antidiabetic effects of wound dressings created using electrospun nanofibers containing Ziziphus jujuba fruit extract (ZJ). These nanofibers were composed of a combination of Polycaprolactone (PCL), Polyvinyl Alcohol (PVA), and Polyhexamethylene Biguanide (PHMB). The process of creating these nanofibers involved electrospinning. The nanofiber products, which included PCL, PCL/PVA, PCL/PVA/ZJ, PCL/PVA/PHMB, and PCL/PVA/PHMB/ZJ, underwent a morphology, physicochemical, and biological assessment. Incorporating PHMB into the nanofibers enhanced the antibacterial properties, effectively preventing bacterial infections in wounds. Furthermore, including ZJ fruit extract in the nanofibers provided antidiabetic properties, making these dressings suitable for diabetic patients. The PCL/PVA/PHMB/ZJ combination exhibited exceptional healing capabilities and superior antibacterial efficiency in MRSA-infected wounds. The histological assay confirmed complete wound healing by day 14, accompanied by reduced inflammation. Based on these findings, using PCL/PVA/PHMB/ZJ as innovative wound dressings is recommended, as they can expedite wound healing while offering significant antidiabetic and antibacterial features. Ultimately, these electrospun nanofibers possess the potential to serve as advanced wound dressings with enhanced antibacterial and anti-diabetes properties. [ABSTRACT FROM AUTHOR]

The earliest silicon-based aerogels attracted attention due to their nanoscale porous structure and high transparency. Still, they need to be more balanced with the poor mechanical properties. Their brittle structure limits the development of this promising new material. Therefore, the goal of this work is to optimize the mechanical properties of aerogels while maintaining transparency. The good mechanical properties of polymers have made them the material of choice for this work. Polyvinyl alcohol (PVA), which can undergo self-crosslinking through side-chain hydroxyl groups forming hydrogen bonds, was chosen as the raw material to simplify and expedite the production process. The production process was experimented with, analyzed, and refined. Considering the time efficiency of the experimental process, a one-step gelling method was invented to facilitate the sol-gel transition. The one-step gelling method maintained the high transparency of PVA aerogels and reduced the time required for the gelation process compared to the freeze-thawing method. This work employs carbon dioxide supercritical drying to ensure minimal structural collapse and maximize the porous structure's retention. The transmittance of PVA aerogels can reach up to 93.67% at a wavelength of 1333 nm. The internal structure of aerogels with different PVA concentrations was observed using a Scanning electron microscope. Applying Beer-Lambert's Law eliminated the effect of sample thickness on transparency. The relationship between the transparency of PVA aerogels, their microstructure, and macroscopic concentration was studied and analyzed for the first time. While ensuring light transmittance, the modulus of the PVA aerogel reached as high as 6.18 ± 0.56 MPa at 13 wt%. [ABSTRACT FROM AUTHOR]

Polyvinyl alcohol (PVA) and chitosan (CS) were mixed with purple tomato anthocyanins (PTA), and then nano zinc oxide (nano-ZnO) or calcium chloride (CaCl2) were added to prepare PVA/CS/PTA/ nano-ZnO (PCP-ZnO) or PVA/CS/PTA/CaCl2 (PCP-CaCl2) films. The effects of nano-ZnO and CaCl2 on the morphology, pH response, color stability, color reversibility, antibacterial activity, antioxidant activity, mechanical properties, water vapor permeability and UV absorption characteristics of films were studied. In addition, its application in intelligent packaging to monitor the freshness of pork was also studied. It was found that both nano-ZnO and CaCl2 can reduce the transmittance of the film in the visible light region, and the film with addition of nano-ZnO was more sensitive to pH. During the 14 day storage period, the film modified with CaCl2 exhibited better color stability. SEM images indicate that the addition of nano-ZnO or CaCl2 alters the microstructure of the film. The mechanical, antibacterial and antioxidant properties and also the application as freshness indicator of PCP-CaCl2 film were superior to those of PCP-ZnO film. Those indicated that the prepared PCP-CaCl2 film is a potential candidate for active and intelligent packaging applications. [ABSTRACT FROM AUTHOR]

This study investigated the ideal performance of non-recirculating Anaerobic Fluidized Bed Reactors (AnFBRs) for treating organic wastewater of varying strengths under low Hydraulic Retention Time (HRT). Four 4.58 L AnFBRs were used to treat synthetic wastewater with an Organic Loading Rate (OLR) ranging from 4.50 to 40.11 gCOD/L-d, and HRT between 1.1 and 4.4 hours. The AnFBRs achieved high removal efficiencies ranging from 83 % to 96 % at steady state, except during the organic shock load, which reduced removal performance to 12 %. Shortened HRT conditions led to a decreasing trend in reactor pH due to an incomplete anaerobic cycle. The modified Stover-Kincannon model estimated the maximum substrate utilization rate of AnFBR's to be 196.08 gCOD/L-d, with a correlation coefficient of 0.98. Under shortended HRT, microbial diversity analysis identified predominant non-filamentous bacterial families, such as Streptococcaceae and Veillonellaceae, which collaborate during biofilm development in anaerobic environments. It was suggested that the porous media provided secure attachment sites for the biomass growth and biofilm formation under shock load and high shear force conditions. While these results offer valuable insights, further studies are needed to confirm these findings and enhance the understanding of the use porous media in non-recirculating AnFBRs. [Display omitted] • Low-density media allow fluidization in a non-recirculating configuration. • The reactor contributes to good performance under severe conditions. • The downward trend in environmental parameters stands for practical limitation. • Microbial diversity result signifies a new assumption in use of porous media. • Maximum utilization rate 196.08 in unit of organic load present ideal conditions [ABSTRACT FROM AUTHOR]

In this work, firstly, the optimal performance ratio of potato starch and polyvinyl alcohol (PVA) was selected, and then the sustainable high-grade food packaging film was developed by adding different amounts (0, 5, 10, 15, 20, and 25 wt% based on the starch mass) of functional additive lignin into the starch - PVA film matrix. Starch - PVA based films with different amounts of lignin were studied from the aspects of morphology, physical and chemical properties, barrier properties, mechanical properties and antioxidant properties. Mechanical tests showed that lignin significantly improved the tensile strength (TS) of the film and effectively blocked the passage of water vapor. Lignin, starch and PVA were linked by hydrogen bond to form polymer network structure, which improved the interfacial compatibility between polymers. The interaction between polymer molecules and the distribution of lignin particles were confirmed by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The high content of phenolic hydroxyl in lignin undergoes proton coupled electron transfer mechanism, which endows the composite film with high antioxidant activity, which is proved by DPPH radical scavenging activity experiment. At the same time, it also gives the film excellent UV barrier and antibacterial properties. The introduction of lignin in this study provides a valuable way for the preparation of multifunctional composite films using biomass as raw materials, and has a potential application prospect in food packaging. [ABSTRACT FROM AUTHOR]

In this paper, a 150-µm-thick flexible γ-Al2O3 nanofiber separator with the tensile strength of 0.22 MPa was prepared from the low-cost aluminum chloride hydroxide/polyvinyl alcohol (PVA)/water precursor materials by electrospinning method. The resultant separator with 3D interconnection nanostructure revealed fiber diameters in the range of 200 to 500 nm. The specific surface area, porosity, and electrolyte uptake of γ-Al2O3 nanofiber separator are 31.5 m2/g, 55%, and 1021%, higher than that of commercial polypropylene (PP) separator and glass fiber (GF) separator. The supercapacitor assembled with the γ-Al2O3 nanofiber separator exhibited a high discharge specific capacitance of 93 F/g at the current density of 1A/g, and there is almost no capacity decay after 10,000 cycles. The energy density of supercapacitor assembled with γ-Al2O3 nanofiber separator is 31.7 Wh/kg at the power density of 562.6 W/kg. Meanwhile, the rate performance of the supercapacitor is improved significantly due to the existence of porous structure and low ion diffusion resistance (0.78 Ω) of γ-Al2O3 nanofiber separator. In addition, the thermal performance of the γ-Al2O3 nanofiber separator is also excellent, which has almost no shrinkage at the temperature of 200 °C and cannot be ignited. Therefore, the obtained γ-Al2O3 nanofibers could serve as a promising alternative separator for a new generation of safe, high-power supercapacitors. [ABSTRACT FROM AUTHOR]

A new integrated electrode-separator-electrolyte hydrogel is designed and prepared, which is composed of organic liquid crystal, polyvinyl alcohol (PVA), polyaniline (PANI), and reduced graphene oxide (rGO). The organic liquid crystal is introduced into PVA hydrogel, effectively improving compatibility between active materials and hydrogel matrix. The PANI active material is in situ polymerized in hydrogel to prepare PANI-double-network hydrogel. It simultaneously acts as electrode, separator, and electrolyte for assembling flexible solid-state supercapacitor. It obtains an area-specific capacitance of 160.2 mF/cm2 and a power density of 101.5 μW/cm2 with an energy density of 21.0 μWh/cm2. This work provides a new method to reduce interfacial resistance of electrode, separator, and electrolyte of flexible solid-state supercapacitor, further improving its electrochemical performance. [ABSTRACT FROM AUTHOR]

Recently, designing and fabricating effectual wound dressings have gained a great deal of interest for the proper management of wound infections and biofilms. The present study is focused on the fabricating and characterizing silver chloride-loaded polyvinyl alcohol nanofibers as antibacterial and conductive wound dressing scaffold by electrospinning technique. Polyvinyl alcohol was subjected to the electrospinning process, and silver chloride was incorporated within PVA nanofibers via in situ reaction between silver nitrate and sodium chloride during the fiber-forming process. The obtained silver-free and silver chloride-containing nanofibers were characterized by different techniques, including scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermal gravimetric analysis (DSC and TGA), etc. The gravimetric method and tensile testing were used to determine the porosity and mechanical properties of the fabricated nanofibers. The nanofiber's in vitro degradation, swelling, and water retention properties were assessed, and their drug loading and release profiles were evaluated by the atomic absorption spectrometry (AAS) method. The wound healing characteristics of the obtained nanofibers, such as antibacterial activity, hemocompatibility, electrical conductivity, and cytotoxicity were evaluated in vitro. The results of this study confirmed that the silver chloride-containing nanofibers exhibit desired physicochemical, morphological, and mechanical properties and could be considered as a potential wound dressing for the management of infectious wounds. On the other hand, the obtained nanofibers showed higher hemocompatibility (less than 5% hemolysis ratio) and cell viability (over 80% after 48 h) as well as appropriate antibacterial activity against two representative strains of Gram-positive and Gram-negative bacteria. [ABSTRACT FROM AUTHOR]

Multiscale fiber hybridization is an essential method for enhancing and toughening cement-based materials. In this study, the influence of the content of calcium carbonate whiskers (CW) and polyvinyl alcohol (PVA) fibers on the flexural properties of cementitious composites containing 1.5% by volume steel fibers was investigated by using the hybridization of CW, PVA fibers, and steel fibers based on the four-point bending notched test. The distribution characteristics of PVA fibers and steel fibers in multiscale hybrid fiber-reinforced cementitious composites (MFRC) were analyzed and evaluated using backscattered electron imaging (BSE). The results demonstrated that the addition of an appropriate amount of CW and PVA fibers effectively improved the flexural performance of steel fiber–reinforced cementitious composites and promoted a more uniform distribution of steel fibers within the matrix. The MFRC with 1% by volume CW, 0.3% by volume PVA fiber, and 1.5% by volume steel fiber (C1P03S15) exhibited the highest flexural toughness coefficient (σb) and fiber dispersion coefficient (γ), which increased by 46.2% and 81.4%, respectively, compared to the control group without CW. Furthermore, a strong correlation between σb and γ was observed through fitting, indicating the potential for guiding practical engineering applications. [ABSTRACT FROM AUTHOR]

Ice slurry is a promising functional fluid with high thermal energy density and high heat transfer rate. However, the agglomeration of the ice particles in flowing ice slurry can cause blocking of tubes. In this study, anti-freeze protein (AFP) and polyvinyl alcohol (PVA) were selected as additives to prevent the agglomeration of ice particles in ice slurry. Ice slurry was generated using the release of the supercooled state of 3 mass% NaCl solution containing the additives. The size of the ice particles in the ice slurry was observed, and the average area of the ice particles was evaluated to reveal the effects of the additives on the ice particle size. Furthermore, the flow behavior of the ice slurry in a tube was observed, and the effects of the additives on the flow behavior and prevention of the agglomeration of the ice particles were evaluated experimentally. It was found that the average area decreased with increasing concentration of the additives, and the effect of AFP on the average area was particularly significant. In the case of without the additives, the ice particles flowed in the tube while the ice particles agglomerated. On the other hand, the ice particles in the ice slurry with the additives flowed without agglomeration in the tube, especially in the case of AFP addition. It was found that AFP prevented the agglomeration of the ice particles in the ice slurry flow. Moreover, the ice slurries with AFP show the significant tendency for pseudo-plastic fluid. [ABSTRACT FROM AUTHOR]

Lepidium perfoliatum seed gum (LPSG) biopolymer was co-electrospun in a hybrid nanofiber (HNF) structure using polyvinyl alcohol and polycaprolactone polymers. The obtained results showed the improvement in the hydrophilicity of HNFs with an increase in the LPSG content. In-vitro assay showed two stages of degradation of HNFs (34% and 4% weight loss within 24 h and 14 days, respectively). The antibacterial assay also showed the antibacterial activity of HNFs against Gram-positive and Gram-negative bacteria species. The biocompatibility of the LPSG-based nanofibers was also justified by the MTT assay against L929 fibroblast cells (97.4% cell viability). [ABSTRACT FROM AUTHOR]

Eggs are one of the low-cost sources of protein and are also perishable, so maintaining their internal quality during storage is particularly important. The current research was carried out with the aim of the effect of nanocomposite coating on the physicochemical changes of eggs during storage for 4 weeks. Uncoated eggs (control) and eggs treated with a two-component coating of polyvinyl alcohol/chitosan (PC), a three-component coating of polyvinyl alcohol/chitosan/montmorillonite (PCM) ), and PCM coatings incorporating concentrations of 2 and 4% garlic extract were evaluated in a total of 5 treatments and 3 replicates in a completely randomized design. The results showed that the concentration-dependent antimicrobial effect of garlic extract was higher against Staphylococcus aureus than Escherichia coli. The prepared films of active three-component PCM nanocomposite had greater thickness, higher tensile strength, and elasticity, lower solubility, less elongation at break, and lower water vapor permeability (p<0.05). At the end of 4 weeks of storage, the eggs coated with active three-component PCM nanocomposites had a thicker shell (0.400 mm) and a stronger shell (0.310 kg), causing less weight loss (About 4 %), Haugh unit (70.00) and yolk index (0.43) were higher and the lowest of total viable count bacteria (4.1 log cfu/ml). Therefore, using the three-component PCM nano-coating containing 4% garlic extract as a biodegradable packaging is possible to maintain the internal quality and eggshell and increase its storage time at ambient temperature. [ABSTRACT FROM AUTHOR]

With the rapid development of industrialization and population surge in modern society, noise pollution has been considered as a serious threat to human beings. In order to effectively reduce noise, the application of sound absorbing textile materials has gradually increased, also the rapid development of acoustic coating consists of conventional fiber layers and polymers. In this work, the surface morphology, micro‐structure and sound absorption properties of polyvinyl alcohol coated fabric and its composites were studied. It was found that the addition of nano‐TiO2 particles can obviously improve the sound absorption properties, and the absorption coefficient is related to fabric thickness. Furthermore, the surface of the coated fabric was compounded with melt‐blown nonwoven fabric, thus to fabricate composite sound absorber. This work indicates the good feasibility and promising application prospect of lightweight polyvinyl alcohol coated fabrics in noise reduction engineering. Highlights: Combination of fiber layers and polymers for acoustic coating materials.Adding inorganic nano‐TiO2 particles with different contents.Different modification methods to improve the dispersion of coating.Composite structure with reduced thickness and increased sound absorption. [ABSTRACT FROM AUTHOR]

Flexible sensors are garnering substantial interests for various promising applications, including medical electronics, environmental monitoring, and wearable devices. Developing a flexible sensor with high compliance, high sensitivity, and high reliability through the construction of a novel composite conductive hydrogel based on the synergistic enhancement effect of conductive polymers and metal ions is a remarkable achievement. Herein, an electronic/ionic‐conductive double network hydrogel (polypyrrole (PPy)/carboxymethyl cellulose (CMC)‐Al3+/polyvinyl alcohol (PVA)) with soft compliance, highly conductivity, and stability is presented. Moreover, owing to the synergistic reinforcement effect of the relatively immobilized "islands" of PPy particles and large amounts of movable "bridges" of aluminum ions (Al3+) within the double network hydrogel, the as‐optimized PPy/CMC‐Al3+/PVA composite gels exhibit excellent conductivity (σ = 3.47 ± 0.25 S m−1) and mechanical properties (E = 18.53 ± 0.67 kPa). Furthermore, it has been developed as strain sensors with relatively high linear sensitivity (gauge factor = 2.58) within a broad linearity range (0–400%). It can also be served as a monitoring devices for subtle physiological signals emanating from various parts of the human body. The robust sensor has great potential to be developed as wearable electronic devices and applied in healthcare monitoring fields. [ABSTRACT FROM AUTHOR]

In this study, polyvinyl alcohol/Nafion nanofibrous composite membranes were produced to investigate their possible application as a polymer electrolyte membrane (PEM) in direct methanol fuel cells. Electrospinning method was used for nanofibrous membrane production, in which the mixture of polyvinyl alcohol (PVA) and Nafion solutions was directly electrospun. Produced nanofibers were subjected to physical stabilization, filler application, and sulfonating to produce composite nanofibrous membranes. PVA and Nafion polymers were used also as filler materials. The properties of resultant composite membranes were compared in terms of water swelling, weight loss in water and methanol solution, thermal stability, morphology, proton conductivity, and methanol permeability. Proton conductivity of the membranes depending on the humidity was also investigated. TGA analysis showed that the membranes had adequate thermal properties regardless of the filler material. The nanofibrous structure was shown to be preserved by scanning electron microscopy (SEM) after treatment with water and methanol solution. It was shown that PVA/Nafion nanofibers displayed proton conductivity after filling process. The use of PVA as a filler material led to higher proton conductivity at 100 RH%. It was reported that proton conductivity could only be obtained at higher relative humidity values (>80% RH). A lower methanol permeability of PVA‐filled membranes was reported. Highlights: PVA/Nafion nanofibrous membranes were produced by electrospinning.PVA and Nafion were also used as pore filling materials.PVA‐filled membranes had higher proton conductivity and lower methanol permeability.Proton conductivity could only be obtained at higher RH% values. [ABSTRACT FROM AUTHOR]

In this study, chromium‐based metal–organic framework (MIL‐101(Cr)) was incorporated into polyvinyl alcohol nanofibers (PVA NFs) via green electrospinning followed by heat treatment to fabricate MIL‐101(Cr)@PVA NFs composite without the need for any organic solvent or other dispersants. The fabricated MIL‐101(Cr)@PVA NFs were comprehensively characterized using a suite of common techniques. Morphological characteristics of MIL‐101(Cr)@PVA NFs showed a fibrous structure with an average diameter of 228 ± 37 nm and decorated with MIL‐101(Cr) particles arranged in a nanoneedle‐like pattern. Subsequently, its adsorption efficiency towards the cationic crystal violet dye (CV) was evaluated through batch adsorption experiments. The influence of various experimental parameters on CV removal efficiency was systematically optimized using a factorial design approach. The Langmuir isotherm and kinetic pseudo‐second‐order (PSO) model provided an excellent fit to the adsorption equilibrium data, indicating a maximum adsorption capacity (qmax) of 344.18 mg/g for MIL‐101(Cr)@PVA NFs compared with 83.94 mg/g for pristine PVA NFs. Furthermore, the MIL‐101(Cr)@PVA NFs composite demonstrated excellent reusability and stability, maintaining a significant portion of its removal capacity even after six adsorption–desorption cycles. These findings highlight the potential of the fabricated composite as a highly efficient and reusable adsorbent for CV removal from wastewater treatment applications. Highlights: The MIL‐101(Cr)@PVA NFs nanocomposite fabricated by electrospinning technique.The MIL‐101(Cr) particle arranged in a nanoneedle‐like pattern in the PVA NFs.Incorporation of MIL‐101(Cr) improved qmax of PVA by 391.5%.The MIL‐101(Cr)@PVA NFs membrane has excellent stability and reusability. [ABSTRACT FROM AUTHOR]

Highlights: Detailed preparation and characterization of new PVA-Alginate beads for Quorum Quenching application. Supercritical CO2 (SC-CO2) drying proved a reliable bead drying technique. Beads' pore structure was modified by changing the composition of the crosslinking solution. Beads with finger-like pores show superior AHL incorporation capacity compared to other bead types. Quorum quenching (QQ) has emerged as an effective biofouling mitigation approach in membrane bioreactors. This study presents new approaches for preparing and characterizing polyvinyl alcohol (PVA) and alginate beads for QQ applications. The effects of change in concentration of PVA, crosslinking solution composition, and the impact of mixture dissolution method on physicochemical, acyl homoserine lactones (AHLs) incorporation and mechanical properties were investigated. Comparisons between evaporative, freeze, and supercritical CO2 drying techniques were followed to characterize textural and structural properties. Beads' structure, mechanical, chemical modification, and textural properties were characterized by scanning electron microscopy, texture profile analysis, Nitrogen physisorption, and attenuated total reflection Fourier transform infrared spectroscopy analysis. Changes in the concentration of PVA and mixture dissolution method impact the bead pore structure, swelling properties, and AHL incorporation. Changes in the composition of the primary crosslinking solution cause modifications in the beads' chain and pore structure. Beads crosslinked using a primary crosslinking solution composed of boric acid and calcium chloride possess internal structures with high chain interconnection and hardness. Meanwhile, beads prepared by blending the boric acid and calcium chloride's primary crosslinking solution with sodium nitrate (named SN-BA) provided new bead types with pores resembling fingers. Nitrogen physisorption analysis revealed the beads have a surface area between 16 m2/g and 23 m2/g with dominating mesopores. The finger-like pores enhanced the AHL permeation compared to beads with interconnected polymer chains. SN-BA beads incorporated around 30% of C6-HSL, 24% of C8-HSL, and 23% of C10-HSL. [ABSTRACT FROM AUTHOR]

Flavored cigarettes are very popular among consumers. However, many essential oils in cigarettes are lost during storage, and the utilization rate of the essential oils during use is low. Therefore, effective packaging and stable sustained release are urgently needed. In this study, a composite electrospun stable nanofiber storage material was prepared for sustained release. Polyethylene glycol, which has good heat storage properties, was selected as the heat storage material to inhibit the release of essential materials during storage. Porous graphene with good thermal conductivity and a porous structure was selected as the heat conductive component to ensure rapid and uniform release. Polyethylene glycol/porous graphene polyvinyl alcohol-mint essential oil sustained-release composite electrospun nanofibers membrane was prepared by electrospinning, and the morphology, composition, thermal properties, and sustained-release properties were tested. The results showed that the composite electrospun nanofiber membrane reduced the loss of mint oil during storage and enabled the rapid release of mint oil at high temperatures. At room temperature, the retention rate of the mint oil was still more than 90% after 120 h, and at a high temperature (75°C) the retention rate was less than 20% after 10 min; that is, 80% of the essential oil material was released within 10 min. [ABSTRACT FROM AUTHOR]

Hydrogel, as one of potential soft materials for articular cartilage, has encountered pressing obstacles, such as insufficient mechanical properties, poor lubrication, and easy to wear. To tackle these, we propose a strong yet slippery polyvinyl alcohol/chitosan (PVA/CS) hydrogel with dual-physically crosslinked networks by harnessing freeze-thawing, salting-out, annealing, and rehydration. High mechanical properties of PVA/CS hydrogel can be readily regulated by adjusting proportion of PVA/CS and annealing temperature. The optimized hydrogel exhibits high mechanical properties with tensile strength of ∼ 19 MPa at strain of 550%, compression strength of ∼ 11 MPa at small strain of 39%, and outstanding toughness and antifatigue owing to the robust physical interactions, including hydrogen bonds, crystallization, and ionic coordination. Moreover, the equilibrium hydrogel shows low friction coefficient of ∼ 0.05 against Al2O3 ball under the condition of 30 N, 1 Hz, with water as the tribological medium, which is close to the lubrication performance of native cartilage. And meanwhile, the proposed cartilage-like slippery hydrogel displays stable long-term lubrication performance for 1 × 105 reciprocating cycles without destructive wear and structure damage. It is therefore believed that the biocompatible cartilage-like slippery hydrogel opens innovative scenarios for developing cartilage-mimicking water-lubricated coating and biomedical implants with satisfactory load-bearing and lubrication performance. [ABSTRACT FROM AUTHOR]

Diabetic wounds, as a complication of diabetes, are slow to heal and seriously affect the quality of life of patients. Functional hydrogel dressing is an effective approach to improve diabetic wound healing. Electrical stimulation (ES) therapy is conducive to promoting cell migration and wound healing. In this work, a multifunctional PPTZ hydrogel wound dressing was developed by freeze-thaw method with polyvinyl alcohol (PVA), phytic acid (PA), tannic acid (TA), and Zinc chloride. The obtained PPTZ hydrogel has good mechanical properties (stress and strain of 700.03 kPa and 575.08%), light transmittance (close to 100%) and antibacterial rate (over 75%). With good biocompatibility, antioxidant abilities and conductivity, the PPTZ hydrogel could effectively promote the healing of diabetic wounds with two weeks under the action of electric field, which provides an auxiliary treatment strategy for diabetic patients. [ABSTRACT FROM AUTHOR]

This study investigates crack growth and propagation in Engineered Cementitious Composite (ECC) beams reinforced with polyvinyl alcohol (PVA) fibers through numerical analysis. The research evaluates numerical findings alongside experimental data from a prior stage. Similar to the experimental phase, the numerical procedure models eight ECC beam specimens, comprising four with 2% and four with 1.5% PVA fibers, utilizing the extended finite element method (XFEM) in Abaqus software. Force-displacement and force-crack mouth opening displacement (CMOD) graphs are generated and compared with experimental results. The study demonstrates XFEM's high accuracy in numerically solving fracture problems and predicting structural behavior, as well as determining parameters assessing ECC behavior during crack growth. Findings reveal that ECC beams with 2% fibers exhibit lower loading capacity and higher displacement values, displaying greater CMOD and ductility compared to those with 1.5% fibers. Additionally, a slight impact on flexural capacity is observed with increasing PVA fiber percentages. [ABSTRACT FROM AUTHOR]

Pythium aphanidermatum is known to cause diseases like damping-off, root rot, stem rot and fruit rot in a wide range of plants. Eventhough many chemical methods have been demonstrated to have the potential to manage these diseases, their benefits are being offset equally by the negative side effects. Therefore, the control of Pythium spp. using natural antifungal agents is of immense significance due to its environmental safety. Here, the plant associated microorganisms with antifungal metabolites have significant promises to be explored both as sustainable biocontrol agents and also as active constituents of antifungal materials. Antimicrobial packaging films prepared using such components can have significant applications to meet the requirements to prevent postharvest loss of agricultural produce by inhibiting the fungal growth. Eventhough there are reports on the development of antimicrobial packaging films for such applications, the use of bacterial extracts with antifungal activity for the same is least investigated. Hence, the present study demonstrates the development of biocomposite films prepared using polyvinyl alcohol (PVA) incorporated with the extracts prepared from bacterial isolates (Serratia sp. NhPB1, Kocuria sp. NhPB49, and Pantoea dispersa NhPB54) previously isolated from the pitcher plant. Here, the individual films were prepared by incorporating 1 mL of bacterial extract in 40 mL of 3% PVA solution and the developed films were then subjected to antifungal activity screening against P. aphanidermatum. The antifungal activity analysis of the films prepared with the incorporation of extracts from Serratia sp. NhPB1, Kocuria sp. NhPB49, and Pantoea dispersa NhPB54 showed remarkable activity against the tested pathogen. The application of biocomposite films on Solanum lycopersicum and Capsicum annuum fruits for its protection from P. aphanidermatum by dip coating method further indicates the promises of developed biocomposite films for active packaging applications. [ABSTRACT FROM AUTHOR]

Encapsulation and nutrient addition in bacterial formulations have disadvantages concerning cell viability during release, storage, and under field conditions. Then, the objective of this work was to encapsulate a bacterial consortium with hydrocarbon-degrading capacities in different matrices composed of cross-linked alginate/ polyvinyl alcohol /halloysite beads (M1, M2, and M3) containing nanoliposomes loaded with or without nutrients and evaluate their viability and release in a liquid medium, and soil (microcosmos). Also, evaluate their capacity to remove total petroleum hydrocarbons (TPH) for 165 days and matrices characterization. The encapsulate consortium showed a quick adaptation to contaminated soil and a percentage of removal (PR) of TPH up to 30% after seven days. All the matrices displayed a PR of up to 90% after 165 days. The matrix M2 displayed significant resistance to degradation and higher cell viability with a PR of 94%. This result supports the encapsulation of bacteria in a sustainable matrix supplemented with nutrients as a well-looked strategy for improving viability and survival and, therefore, enhancing their effectiveness in the remediation of hydrocarbon-contaminated soils. [ABSTRACT FROM AUTHOR]

Fricke gel dosimeters are appropriate candidates for gamma dosimetry. Polyvinyl alcohol Fricke gel dosimeters are the most recent introduced gel dosimeters which have low ion diffusion. In this work, samples of ferrous-xylenol orange-polyvinyl alcohol gel dosimeters were prepared and characterized using optical spectroscopy. Using win XCOM program and the elemental composition of the gel, the mass attenuation coefficients for photons were evaluated. The results exhibited that the prepared gel is the nearly radiological blood-, soft tissue- and water-equivalent. The 60Co gamma cell unit was used to irradiate the gel samples. A dose range response was found linear from 10 to 30 Gy and suitable for blood irradiation dosimetry. Additionally, the gel response good repeatability was confirmed by the coefficient of variation calculations. Furthermore, chemical yield of the gel was estimated to be 34.6. The good characteristics of the prepared gel make it appropriate for dosimetry of blood irradiators. [ABSTRACT FROM AUTHOR]

Polyvinyl Alcohol (PVA) and Chitosan were combined with tellurium (IV) oxide (Te2O4) and copper oxide (CuO) nanoparticles to create a PVA/Chitosan–Te2O4/CuO nanocomposite, aiming to enhance its structural, thermal, and electrical properties. Te2O4 and CuO nanoparticles were synthesized using laser ablation. The study examined how varying CuO nanoparticle concentrations affected the electrical properties of the films. XRD analysis confirmed the presence of Te2O4 and CuO with their respective crystal structures. FTIR results indicated interactions between PVA/Chitosan matrix and Te2O4/CuO nanoparticles, evidenced by a reduced absorption band. SEM images showed well-distributed CuO nanoparticles within the PVA/Chitosan matrix. Optical data revealed an absorption edge at 216 nm, related to electronic transitions, and increased absorption with longer CuO laser ablation times. Thermal analysis showed that the nanocomposite decomposed at higher temperatures (550–600 °C) with greater mass loss compared to the pure blend, suggesting improved thermal stability. Additionally, the nanocomposite exhibited higher real conductivity, indicating enhanced charge transport due to the Te2O4/CuO nanoparticles. [ABSTRACT FROM AUTHOR]

Interfacial solar-driven evaporation technology shows great potential in the field of industrial seawater desalination, and the development of efficient and low-cost evaporation materials is key to achieving large-scale applications. Hydrogels are considered to be promising candidates; however, conventional hydrogel-based interfacial solar evaporators have difficulty in simultaneously meeting multiple requirements, including a high evaporation rate, salt resistance, and good mechanical properties. In this study, a Janus sponge-like hydrogel solar evaporator (CPAS) with excellent comprehensive performance was successfully constructed. The introduction of biomass agar (AG) into the polyvinyl alcohol (PVA) hydrogel backbone reduced the enthalpy of water evaporation, optimized the pore structure, and improved the mechanical properties. Meanwhile, by introducing hydrophobic fumed nano-silica aerogel (SA) and a synergistic foaming-crosslinking process, the hydrogel spontaneously formed a Janus structure with a hydrophobic surface and hydrophilic bottom properties. Based on the reduction of the evaporation enthalpy and the modulation of the pore structure, the CPAS evaporation rate reached 3.56 kg m-2 h-1 under one sun illumination. Most importantly, owing to the hydrophobic top surface and 3D-interconnected porous channels, the evaporator could work stably in high concentrations of salt-water (25 wt% NaCl), showing strong salt resistance. Efficient water evaporation, excellent salt resistance, scalable preparation processes, and low-cost raw materials make CPAS extremely promising for practical applications. [ABSTRACT FROM AUTHOR]

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The blockage of gas transmission pipelines due to gas hydrates poses a significant challenge for the gas industry. Low‐dosage hydrate inhibitors (LDHI) are utilized to influence the kinetics of hydrate formation, including nucleation, growth, and/or agglomeration. In the current study, a series of batch, isochoric, and isothermal tests were carried out to investigate the impacts of two LDHIs, poly N‐vinylpyrrolidone (PVP) and polyvinyl alcohols (PVA). This study examined the influence of these inhibitors on nucleation and growth of ethane+propane mixture in the presence of kaolin nanoparticles. In laboratory studies and using pure constituents, the rate of hydrate formation is low to investigate the inhibitors effect. To enhance the rate of hydrate formation, kaolin nanoparticles were utilized as they serve as a suitable representative for solid minerals commonly found in pipelines. The gas phase's compositional change were measured using a gas chromatograph. The results revealed that the growth stage of mixed‐gas exhibited two distinct steps, attributed to the formation of two different structures known as structure II and structure I. During the first step, structure II was formed, and the cavities were occupied by both gas components. In the second stage, structure I was formed by ethane. The effect of temperature on the induction time (nucleation rate) and the growth rate during the second stage was lower than that at the first stage. The increase in PVA concentration resulted in an increase in the induction time and a decrease in the rate of growth during the first stage. The performance of PVA was found to be affected by temperature. Lower temperatures resulted in the formation of less foam, providing improved performance for PVA at −0.5°C. PVP had a stronger impact on induction time and both growth steps compared to PVA, indicating stronger inhibitory impact of PVP on nucleation of hydrates initiated by propane and the growth of both propane and ethane hydrates. [ABSTRACT FROM AUTHOR]