Electron Microscopy Image Analysis Research Articles

Performance of glass epoxy composites under combined effect of in‐plane fiber waviness with circular cutout through tensile test, and image processing technique

AbstractPresent study comprehensively explores the phenomenon of in‐plane fiber waviness in glass/epoxy fiber reinforced polymer (GFRP) composites. Utilizing a pioneering technique that employs a semi‐circular bar to induce controlled fiber waviness, coupled with image processing using OpenCV library in Python coding for precise measurement and analysis of in‐plane fiber waviness. This defect is commonly found in components fabricated with fiber‐reinforced composites. During the process of manufacturing fibers may deviate from their intended orientation due to process variables or resin flow dynamics. Understanding in‐plane fiber waviness is crucial due to its impact on mechanical properties of composites. It is essential for optimizing manufacturing processes and ensuring enhanced structural performance in diverse engineering applications through analysis of strength and failure mechanism. A novel study was conducted by introducing a circular cutout within the fiber waviness region to investigate the combined effect of multiple defects. The experimental tensile test reveals that as waviness ratio (WR) increases a significant decrease in its tensile strength and vice versa. The study incorporates scanning electron microscopy (SEM) image analysis to examine composite failure. By advancing the understanding of in‐plane fiber waviness and its implications, this research significantly contributes to ongoing efforts in composite design and optimization.Highlights Adopting a cutting‐edge method to create controlled fiber waviness that makes use of a semi‐circular bar. Image processing with Python code that makes use of the OpenCV package to precisely measure and analyze in‐plane fiber waviness. A new investigation was carried out to examine the combined effect of multiple flaws by creating a circular cutout within the fiber waviness zone.

Molecular model of a bacterial flagellar motor in situ reveals a "parts-list" of protein adaptations to increase torque.

One hurdle to understanding how molecular machines work, and how they evolve, is our inability to see their structures in situ . Here we describe a minicell system that enables in situ cryogenic electron microscopy imaging and single particle analysis to investigate the structure of an iconic molecular machine, the bacterial flagellar motor, which spins a helical propeller for propulsion. We determine the structure of the high-torque Campylobacter jejuni motor in situ, including the subnanometre-resolution structure of the periplasmic scaffold, an adaptation essential to high torque. Our structure enables identification of new proteins, and interpretation with molecular models highlights origins of new components, reveals modifications of the conserved motor core, and explain how these structures both template a wider ring of motor proteins, and buttress the motor during swimming reversals. We also acquire insights into universal principles of flagellar torque generation. This approach is broadly applicable to other membrane-residing bacterial molecular machines complexes.

Demonstration of 1 V Reliable FeRAM Operation: Vc Engineering Using Quasi-Chirality of Hf1-xZrxO2 in a Nanolaminate Structure.

Hafnia thin films are known to demonstrate excellent performance with strong ferroelectricity and high scalability, making them promising candidates for CMOS-compatible materials. However, the reliability of ferroelectric devices must be further improved. This study developed a Hf1-xZrxO2 ferroelectric capacitor with a nanolaminate structure that operated at remarkably low voltages, demonstrating excellent retention (>10 years/85 °C) and endurance (>1010 cycles). The exceptional performance is attributed to the presence of thin tetragonal phase layers within the thick ferroelectric layers, which decreased the switching barrier in the nanolaminate films. Further, we verified phase crystallization via a detailed analysis of high-resolution transmission electron microscopy images. The improved switching propagation in the nanolaminate films was confirmed through switching speed measurements and theoretical models. Furthermore, we addressed pinching issues by precisely controlling the Hf/Zr ratio and O3 treatment. The initial imprint and retention characteristics were improved by interfacial engineering. Moreover, by reducing the thickness, we have achieved reliable operation at 1.0 V with a 5.5 nm-thick device while maintaining high retention and endurance. This study is a significant step toward the realization of the longstanding problem of ferroelectric random access memory operation voltage with respect to endurance and retention characteristics.

Fabrication and characterization of an electrospun silk fibroin/gelatin transparent graft material for corneal epithelial regeneration

The damaged corneal epithelial causing loss of vision can be restored by epithelial tissue regeneration through tissue engineering approach that provides an engineered corneal substitute with appropriate properties and nanofibrous architecture. This works reports a polymeric matrix that was derived from silk fibroin (SF) and gelatin (GE) natural polymer blend with optimized composition resembling the structure and function of the native epithelial tissue. SF/GE blend spinning solutions prepared with different volume ratios of SF/GE: 70/30, 50/50, and 30/70 were used to fabricate electrospun mats. The fabricated two-dimensional mats had nanofibrous porous architecture having interconnected pores with pore size range of 175–267 nm suitable for corneal epithelial regeneration and 891.2–558 nm fiber diameter range as revealed by scanning electron microscopic image analysis. The performed Fourier transform infrared spectra confirmed the presence of individual polymers in the scaffolds and the scaffolds are hydrophilic in nature. Among the scaffolds, SF/GE 70:30 and SF/GE 50:50 composition possess desired porosity range of 87–88%. The tensile strength was slightly decreased with increase in GE content and the strength obtained was in the range 2.74–2.26 Mpa. An enhanced transparency was obtained with increased GE concentration, the transparency range of 73–82% observed with SF/GE:50/50 matches with the transparency of natural corneal epithelium. The biocompatibility of the scaffolds was confirmed by cell attachment, cytotoxicity and ROS evaluation by culturing rabbit corneal fibroblast cells (SIRC) on the scaffolds. Among the scaffolds, SF/GE: 70/30 exhibited the highest cell viability, but with less transparency ranging 55–71%. Therefore, considering all the properties, SF/GE with 50:50 ratio scaffold may be a suitable substrate in the field of corneal tissue engineering.

Ethanolic Extract from Echinacea purpurea (L.) Moench Inhibits Influenza A/B and Respiratory Syncytial Virus Infection in vitro: Preventive Agent for Viral Respiratory Infections.

Among the most frequent causes of respiratory infections in humans are influenza A virus H1N1 (H1N1), influenza B virus (IVB), and respiratory syncytial virus (RSV). Echinacea is a perennial wildflower belonging to the Asteraceae family. Echinacea purpurea (L.) Moench is a species belonging to the Echinacea genus. Its characteristic compound, chicoric acid (CA), is known for its physiological activities, including antiviral effects and immune enhancement. Activities of E. purpurea 60% ethanol extract (EPE) and CA in inhibiting infections caused by H1N1, IVB, and RSV subtype A (RSV-A) were evaluated through plaque inhibition tests, quantification of viral gene expression, and analysis of transmission electron microscopy (TEM) images. Additionally, inhibitory activities of EPE and CA for hemagglutination and neuraminidase (NA) of H1N1 and IVB were determined. In the plaque reduction assays, both EPE and CA reduced infectivity against H1N1, IVB, and RSV-A. Furthermore, quantitative real-time polymerase chain reaction analysis revealed that EPE and CA reduced gene expression levels for H1N1, IVB, and RSV-A, whereas TEM image analysis confirmed their inhibitory effects on host cell infection by these viruses. Hemagglutination assays exhibited the ability of EPE and CA to hinder H1N1 and IVB attachment to host cell receptors. Furthermore, EPE and CA displayed inhibition activity against the NA of H1N1 and IVB. These findings suggest that EPE and CA can suppress the infection and propagation of H1N1, IVB, and RSV-A, demonstrating their potential as preventive and therapeutic agents for viral respiratory infections or as ingredients for health functional foods.

Microfluidics assisted green synthesis of copper oxide nanoparticles from the aqueous leaf extract of Ipomoea quamoclit L. with its antimicrobial and antioxidant activity

IntroductionGreen nanosynthesis of medicinal plants are useful for the development of antibiotic agents. In this work, we have explored the antimicrobial and antioxidant activity of green synthesised copper oxide (CuO) nanoparticles (NPs) from tropical medicinal plant Ipomoea quamoclit L. MethodsWith the aid of microfluidic technology, a low-cost, polydimethylsiloxane (PDMS) lab-on-chip micromixer for green nanosynthesis of CuO nanoparticle using Ipomoea quamoclit is presented. The UV–Vis characteristics, Fourier Transform Infra-red (FTIR) spectrum, antimicrobial and antioxidant response using DPPH and hydrogen peroxide (H2O2) were reported. The antimicrobial efficacy of the synthesised CuO-NPs is tested against two-gram positive bacteria Staphylococcus aureus, Micrococcus luteus, two gram negative bacteria, Enterobacter cloacae, Klebsiella pneumoniae and two fungi species Candida albicans, Aspergillus niger. ResultsUV–Vis spectrum for the synthesised CuO-NPs showed the absorbance at 670 nm, scanning electron microscope (SEM) image analysis and dynamic light scattering (DLS) analysis confirmed the presence of spherical shaped nanoparticle sized between 65 and 94.5 nm. The presence of bioactive functional groups of N-H, C-H and C=0 stretching was identified using Fourier Transform Infrared spectroscopy (FTIR). The maximum mean zone of inhibition obtained was 10.45±0.25 mm for fungi A. niger. The antioxidant activity using DPPH scavenging assay and hydrogen peroxide scavenging assay showed the IC50 value 33.94 μg/ml and 42.54 μg/ml respectively. ConclusionsThe obtained results reveal the potential of CuO-NPs synthesised from I. quamoclit L. as a remarkable medicinal entity for wound healing, respiratory infection, fungal infection and urinary tract infection along with the improved antimicrobial and antioxidant activity.

Atomic-level Quantitative Analysis of Electronic Functional Materials in Aberration-corrected STEM

Abstract The stable sub-angstrom resolution of the aberration-corrected scanning transmission electron microscope (AC-STEM) makes it an advanced and practical characterization technique for all materials. Owing to the prosperous advancement in computational technology, specialized software and programs have emerged as potent facilitators across the entirety of electron microscopy characterization process. Utilizing advanced image processing algorithms promotes the rectification of image distortions, concurrently elevating the overall image quality to superior standards. Extracting high-resolution, pixel-level discrete information and converting it into atomic-scale, followed by performing statistical calculations on the physical matters of interest through quantitative analysis, represents an effective strategy to maximize the value of electron microscope images. The efficacious utilization of quantitative analysis of electron microscope images has become a progressively prominent consideration for materials scientists and electron microscopy researchers. This article offers a concise overview of the pivotal procedures in quantitative analysis and summarizes the computational methodologies involved from three perspectives: contrast, lattice and strain, as well as atomic displacements and polarization. It further elaborates on practical applications of these methods in electronic functional materials, notably in piezoelectrics/ferroelectrics and thermoelectrics. It emphasizes the indispensable role of quantitative analysis in fundamental theoretical research, elucidating the structure-property correlations in high-performance systems, and guiding synthesis strategies.

Impact of spraying commercial Bentonite Nanoclay on fortification of the mortar as Nano Sprying Technique (NST) in heritages and historical buildings

Spraying Bentonite NanoClay as an innovative idea satisfied an urgent need for conservation of historical brick constructions. This research explores the application of Nanotechnology as a Nano-Geotechnics (NaG) and Nano Ground Improvement (NGI) techniques for fortifying the mortar between bricks in historical buildings against some environmental erosive factors. Bentonite Nanoparticles were selected because of their compatibility with mortar. They were applied via Nano Spray to mitigate holes and cracks caused by erosion. Various percentages of bentonite NanoClay (2–10%) Spray and the number of times to spray on the mortar were evaluated. Validation through field emission scanning electron microscopy imaging (FESEM/SEM), X-Ray differaction and Fluorescence analyses (XRD/XRF), Inductively coupled plasma optical emission spectroscopy (ICP-OES), Brunauer–Emmett–Teller (BET), porosity tests, water absorption time measurement, and weathering tests confirmed the efficacy and long-term stability of this method. The result indicated that double spraying of a 2% NanoClay solution proved most effective in reducing porosity, declining water absorption, and enhancing resistance to freezing and rain.

Cobalt-Doped ZnO Nanocomposits for Efficient Dye Degradation: Charge Transfer.

Doping enhances the optical properties of high-band gap zinc oxide nanoparticles (ZnO NPs), essential for their photocatalytic activity. We used the combustion approach to synthesize cobalt-doped ZnO heterostructure (CDZO). By creating a mid-edge level, it was possible to tune the indirect band gap of the ZnO NPs from 3.1 eV to 1.8 eV. The red shift and reduction in the intensity of the photoluminescence (PL) spectra resulted from hindrances in electron-hole recombination and sp-d exchange interactions. These improved optical properties expanded the absorption of solar light and enhanced charge transfer. The field emission scanning electron microscopy (FESEM) image and elemental mapping analysis confirmed the CDZO's porous nature and the dopant's uniform distribution. The porosity, nanoscale size (25-55 nm), and crystallinity of the CDZO were further verified by high-resolution transmission electron microscopy (HRTEM) and selected area electron image analysis. The photocatalytic activity of the CDZO exhibited much greater efficiency (k=0.131 min-1) than that of ZnO NPs (k=0.017 min-1). Therefore, doped heterostructures show great promise for industrial-scale environmental remediation applications.

Aquaporin-3a Dysfunction Impairs Osmoadaptation in Post-Activated Marine Fish Spermatozoa.

Spermatozoon volume regulation is an essential determinant of male fertility competence in mammals and oviparous fishes. In mammals, aquaporin water channels (AQP3, -7 and -8) have been suggested to play a role in spermatozoon cell volume regulatory responses in the hypotonic female oviduct. In contrast, the ejaculated spermatozoa of marine teleosts, such as the gilthead seabream (Sparus aurata), experience a high hypertonic shock in seawater, initially resulting in an Aqp1aa-mediated water efflux, cell shrinkage and the activation of motility. Further regulatory recovery of cell volume in post-activated spermatozoa is mediated by Aqp4a in cooperation with the Trpv4 Ca2+ channel and other ion channels and transporters. Using a paralog-specific antibody, here, we show that seabream spermatozoa also express the aquaglyceroporin AQP3 ortholog Aqp3a, which is highly accumulated in the mid posterior region of the spermatozoon flagella, in a similar pattern to that described in mouse and human sperm. To investigate the role of Aqp3a in seabream sperm motility, we used a recently developed AQP3 antagonist (DFP00173), as well as the seabream Aqp3a-specific antibody (α-SaAqp3a), both of which specifically inhibit Aqp3a-mediated water conductance when the channel was heterologously expressed in Xenopus laevis oocytes. Inhibition with either DFP00173 or α-SaAqp3a did not affect sperm motility activation but did impair the spermatozoon motion kinetics at 30 s post activation in a dose-dependent manner. Interestingly, in close resemblance to the phenotypes of AQP3-deficient murine sperm, electron microscopy image analysis revealed that both Aqp3a inhibitors induce abnormal sperm tail morphologies, including swelling and angulation of the tail, with complete coiling of the flagella in some cases. These findings suggest a conserved role of Aqp3a as an osmosensor that regulates cell volume in fish spermatozoa under a high hypertonic stress, thereby controlling the efflux of water and/or solutes in the post-activated spermatozoon.

Compatibility study of recycled Polypropylene (PP)/Poly(ethylene terephthalate) (PET) blends nanocomposites with PP‐g‐MAH: Modeling of twin screw extrusion

AbstractAlthough the utilization of recycled polymers is essential to sustain the environment, conventional recycled polymers face limitations in application due to the degradation of their properties caused by impurities. To solve the problem the performance deterioration of these recycled polymers, this study aimed to enhance their compatibility by chemically adding polypropylene‐graft‐maleic anhydride (PP‐g‐MAH) and physically manipulate a screw profile by using an extrusion simulation program. As a result of applying the optimized extrusion process set by the simulation program, significant improvements in the compatibility and dispersion of fillers within the polymer were observed through scanning electron microscopy image analysis. In addition, through detailed analysis of rheological data, the positive impact of adding compatibilizer and changing screw profile on rheological properties was demonstrated. As the compatibility of recycled polymer blends improved, tensile strength increased by approximately two‐fold and thermal conductivity was significantly improved, which were decisive factors in dramatically enhancing the performance of recycled polymers. These improved polymer properties provide an opportunity for recycled polymers to be applied more broadly and will expand the potential for new applications in various industrial fields.

Analysis of Defect Structures during the Early-Stages of PVT Growth of 4H-SiC Crystals

To better understand the effects of various growth parameters during the early-stages of PVT growth of 4H-SiC on resulting defect structures, multiple short duration growths have been carried out under varying conditions of seed quality, nucleation rate, thermal gradients, and N incorporation. Besides the replication of TSDs/TMDs and TEDs as well as the deflection of TSDs/TMDs into Frank dislocations, synchrotron monochromatic beam x-ray topography (SMBXT) studies also reveal the formation of stacking faults bounded by Frank dislocations. Using ray tracing simulations to characterize the Frank dislocations, three types of stacking faults are revealed: Type 1 stacking fault resulting from 2D nucleation of 6H polytype on terraces; Type 2 stacking fault resulting from macrostep overgrowth of the surface growth spiral steps of TSDs/TMDs which separate into c/2 or c/4 increments; Type 3 stacking fault resulting from vicinal step overgrowth of surface growth spiral steps of TSDs/TMDs which separate into c/4 and 3c/4 increments. Analysis of atomic resolution scanning transmission electron microscopy (STEM) images reveals the mechanism of the Type 3 fault.

Sustainable management of peanut damping-off and root rot diseases caused by Rhizoctonia solani using environmentally friendly bio-formulations prepared from batch fermentation broth of chitinase-producing Streptomyces cellulosae.

Soil-borne plant diseases represent a severe problem that negatively impacts the production of food crops. Actinobacteria play a vital role in biocontrolling soil-borne fungi. The target of the present study is to test the antagonistic activity of chitinase-producing Streptomyces cellulosae Actino 48 (accession number, MT573878) against Rhizoctonia solani. Subsequently, maximization of Actino 48 production using different fermentation processes in a stirred tank bioreactor. Finally, preparation of bio-friendly formulations prepared from the culture broth of Actino 48 using talc powder (TP) and bentonite in a natural as well as nano forms as carriers. Meanwhile, investigating their activities in reducing the damping-off and root rot diseases of peanut plants, infected by R. solani under greenhouse conditions. Actino 48 was found to be the most significant antagonistic isolate strain at p ≤ 0.05 and showed the highest inhibition percentage of fungal mycelium growth, which reached 97%. The results of scanning electron microscope (SEM) images analysis showed a large reduction in R. solani mycelia mass. Additionally, many aberrations changes and fungal hypha damages were found. Batch fermentation No. 2, which was performed using agitation speed of 200rpm, achieved high chitinase activity of 0.1163 U mL- 1 min- 1 with a yield coefficient of 0.004 U mL- 1 min- 1 chitinase activity/g chitin. Nano-talc formulation of Actino 48 had more a significant effect compared to the other formulations in reducing percentages of damping-off and root rot diseases that equal to 19.05% and 4.76% with reduction percentages of 60% and 80%, respectively. The healthy survival percentage of peanut plants recorded 76.19%. Furthermore, the nano-talc formulation of Actino 48 was sufficient in increasing the dry weight of the peanut plants shoot, root systems, and the total number of peanut pods with increasing percentages of 47.62%, 55.62%, and 38.07%, respectively. The bio-friendly formulations of actinobacteria resulting from this investigation may play an active role in managing soil-borne diseases.

Advancing X‐Band Electromagnetic Interference Shielding: Single‐Layer Thin Films of Fe3O4‐MWCNT (1:2)‐PVDF Meta‐Nanocomposite Fabricated by Low‐Cost Drop‐Casting Process

This study, investigate of ternary thermoplastic fluoropolymer blend nanocomposite (NC) system for improved microwave (MW) shielding, consisting of polyvinyl dimethylamine fluoride (PVDF) and Fe3O4‐multiwalled carbon nanotube (MWCNT) (1:2) NC. Using a hydrothermal process, complex hierarchical nanostructures (NSs) of Fe3O4‐MWCNT (1:2) NC are produced. These NSs are then integrated using a drop‐casting technique into PVDF matrices with different wt% (20, 40, and 60 wt%) and thicknesses (20, 50, and 80 μm). The single‐layer thin films (SLFs) with the Fe3O4‐MWCNT (1:2)‐PVDF matrix are successfully produced as a consequence of this approach. The presence of FeOC bonding from X‐ray photoelectron spectroscopy (XPS) analysis confirms chemical interaction, while scanning electron microscopy (SEM–Energy dispersive spectroscopy EDX) imaging analysis for material homogeneity. Moreover, the SLFs of Fe3O4‐MWCNT (1:2)‐PVDF (20, 40, and 60 wt% for 80 μm thickness) are newly discovered meta‐nanocomposites (MNCs) properties, which are evidenced by negativeMW real complex permittivity (−274.4, −271.2, and −136.4), superior attenuation constant (12862.73, 16265.18, and 12256.34), and higher alternating current (AC)electrical conductivities (1020.8, 1174.6, and 727.7 S m−1). The synergistic impact of higher attenuation and AC conductivity of MNCs results in an increased average MW shielding effectiveness of ≈33.28 dB for Fe3O4‐MWCNT (1:2)‐PVDF 20 wt% MNCs (≈80 μm).

Melt electrowriting of poly(ϵ-caprolactone)—poly(ethylene glycol) backbone polymer blend scaffolds with improved hydrophilicity and functionality

Melt electrowriting (MEW) is an additive manufacturing technique that harnesses electro-hydrodynamic phenomena to produce 3D-printed fibres with diameters on the scale of 10s of microns. The ability to print at this small scale provides opportunities to create structures with incredibly fine resolution and highly defined morphology. The current gold standard material for MEW is poly(ϵ-caprolactone) (PCL), a polymer with excellent biocompatibility but lacking in chemical groups that can allow intrinsic additional functionality. To provide this functionality while maintaining PCL’s positive attributes, blending was performed with a Poly(Ethylene Glycol) (PEG)-based Acrylate endcapped Urethane-based Precursor (AUP). AUPs are a group of polymers, built on a backbone of existing polymers, which introduce additional functionality by the addition of one or more acrylate groups that terminate the polymer chain of a backbone polymer. By blending with a 20kDa AUP-PEG in small amounts, it is shown that MEW attributes are preserved, producing high-quality meshes. Blends were produced in various PCL:AUP weight ratios (100:0, 90:10 and 0:100) and processed into both solvent-cast films and MEW meshes that were used to characterise the properties of the blends. It was found that the addition of AUP-PEG to PCL significantly increases the hydrophilicity of structures produced with these polymers, and adds swelling capability compared to the non-swelling PCL. The developed blend (90:10) is shown to be processable using MEW, and the quality of manufactured scaffolds is evaluated against pure PCL scaffolds by performing scanning electron microscopy image analysis, with the quality of the novel MEW blend scaffolds showing comparable quality to that of pure PCL. The presence of the functionalisable AUP material on the surface of the developed scaffolds is also confirmed using fluorescence labelling of the acrylate groups. Biocompatibility of the MEW-processable blend was confirmed through a cell viability study, which found a high degree of cytocompatibility.

Investigating correlations between microstructural characteristics and mechanical properties of coral sand mortar with different silica fume contents

The use of coral sand in concrete and mortar for ocean engineering has led to significant reductions in construction costs and improved construction efficiency. However, this approach poses challenges such as low strength, high brittleness, and high porosity. To address these challenges, this study incorporated silica fume to enhance the mechanical properties of the mortar and investigated the effects of different silica fume contents on the hydration process, pore structure, and strength of coral sand mortar. Additionally, this study introduced a novel iterative approach combining low-field nuclear magnetic resonance and scanning electron microscopy image analysis to determine transverse relaxivity (ρ2). During the early hydration process, the intensity spectrum of coral mortar exhibited three peaks at 298, 1841, and 299 au, corresponding to transverse relaxation times (T2) of 0.64, 6.83, and 83.10 ms, respectively. Over a 6 h hydration period, the spectrum of the specimen prepared with white cement exhibited an additional peak that gradually merged with the main peak. As the curing period extended from 7 to 28 days, the porosity of coral sand mortar decreased by 3.77–4.55 %, while the strength increased by 7.43–14.35 MPa across silica fume contents ranging from 6 % to 24 %. With increasing silica fume content, the calcium–silicon ratio of the samples gradually decreased, promoting the formation of more floccus C–S–H gels. Consequently, the sample porosity first decreased slightly. After 28 days of curing, the coral sand mortar containing 12 % silica fume exhibited the highest strength owing to the increased amount of floccus C–S–H gels. These gels gradually filled the pores between the fibrous C–S–H gels, forming a compact spatial reticular structure. This structure mitigated the adverse impact of high porosity on mortar strength.

Development of UV protective and antimicrobial CVC fabric using colloidal zinc oxide solution with carrot and orange peel extract

AbstractChronic exposure to ultraviolet (UV) radiation can cause degenerative changes in the cells, fibrous tissues and blood vessels. Moreover, microbiological attacks pose severe risks to human health and are a major cause of sickness worldwide. The aim of this work is to develop UV protective and antimicrobial materials using zinc oxide (ZnO) colloidal solution with carrot and orange peel extract. Treated samples were subjected to color strength (K/S value) measurement, scanning electron microscope (SEM) image analysis, attenuated total reflectance (ATR) Fourier transform infrared (FTIR) spectroscopy analysis, ultraviolet protection factor (UPF) test, bacterial reduction rate analysis and bursting strength measurement. The study revealed that the treated fabric exhibited remarkable UV protection capabilities, as evidenced by low transmission percentages across UV wavelengths and an outstanding UPF rating of 50, signifying excellent defense against harmful ultraviolet radiation. Additionally, antibacterial tests revealed the significant effectiveness of the treatment against common bacterial strains, with impressive reduction rates for Staphylococcus aureus (99.99%) and Escherichia coli (99.17%). Furthermore, the fabric's bursting strength, both in dry and wet conditions, remained nearly unchanged after treatment. ATR‐FTIR analysis and SEM imaging provided insights into the phytochemical compounds that give protection against UV composition (44.63–49.91) and surface morphology of the treated fabric, elucidating the mechanisms behind its enhanced properties. Due to the availability of carrot and orange peel in nature and low cost of raw materials, this process can be considered to apply commercially for further research purposes.Highlights Utilization of carrot and orange peel waste. Successful application of zinc oxide for antibacterial and ultraviolet protective materials. Excellent defense against harmful ultraviolet radiation. Significant effectiveness against common bacterial strains. Low cost and commercially viable functional materials.

In situ fabrication of atomically adjacent dual-vacancy sites for nearly 100% selective CH4 production

The photocatalytic CO2-to-CH4 conversion involves multiple consecutive proton-electron coupling transfer processes. Achieving high CH4 selectivity with satisfactory conversion efficiency remains challenging since the inefficient proton and electron delivery path results in sluggish proton-electron transfer kinetics. Herein, we propose the fabrication of atomically adjacent anion-cation vacancy as paired redox active sites that could maximally promote the proton- and electron-donating efficiency to simultaneously enhance the oxidation and reduction half-reactions, achieving higher photocatalytic CO2 reduction activity and CH4 selectivity. Taking TiO2 as a photocatalyst prototype, the operando electron paramagnetic resonance spectra, quasi in situ X-ray photoelectron spectroscopy measurements, and high-angle annular dark-field-scanning transmission electron microscopy image analysis prove that the VTi on TiO2 as initial sites can induce electron redistribution and facilitate the escape of the adjacent oxygen atom, thereby triggering the dynamic creation of atomically adjacent dual-vacancy sites during photocatalytic reactions. The dual-vacancy sites not only promote the proton- and electron-donating efficiency for CO2 activation and protonation but also modulate the coordination modes of surface-bound intermediate species, thus converting the endoergic protonation step to an exoergic reaction process and steering the CO2 reduction pathway toward CH4 production. As a result, these in situ created dual active sites enable nearly 100% CH4 selectivity and evolution rate of 19.4 μmol g-1 h-1, about 80 times higher than that of pristine TiO2. Thus, these insights into vacancy dynamics and structure-function relationship are valuable to atomic understanding and catalyst design for achieving highly selective catalysis.

Rice husk-derived cobalt silica as effective peroxymonosulfate activator for degradation of organic pollutants

In this study, mesoporous silica was synthesized from rice husks, and subsequently used to prepare a cobalt silica (Co/SiO2) catalyst via a simple sol–gel approach. The synthesized Co/SiO2 catalyst was thoroughly characterized. The analysis of the scanning electron microscopy (SEM) images revealed silica particles with sizes of nearly 20 nm. Energy-dispersive X-ray analysis showed a good Co dispersion on the catalyst surface with a Co content of 7.7 %. The Co/SiO2 catalyst was then utilized as a peroxymonosulfate (PMS) activator to degrade reactive black 5 (RB5). Furthermore, the impact of various parameters on RB5 degradation was analyzed. The Co/SiO2 catalyst demonstrated excellent performance and completely degraded RB5 within 8 min with a rate constant of 5.5 × 10−1 min−1 at an extremely low dosage of 0.05 g/L. Furthermore, the degradation rate increased with temperature, and the activation energy was 51.5 kJ/mol. The analysis of the quenching and electron paramagnetic resonance experiments showed that SO4• −, HO•, 1O2, and O2• − were produced, with 1O2 being the predominant reactive species. Notably, the catalyst remained effective when tested in actual water environments and could degrade various other dyes and tetracycline. To facilitate catalyst recovery through filtration, Co/SiO2 was embedded in crosslinked chitosan beads. The bead catalyst demonstrated comparable performance to pristine Co/SiO2 and could be reused for five cycles.

Thermomechanical and physicochemical evolution of meat‐analogue based fried foods

SummaryThis study aimed to get mechanistic insights on the evolution of major quality attributes of meat‐analogue (MA) based batter‐coated fried products. Wheat and rice flour‐based batter systems were used to coat a MA. The products were deep‐fried at 180°C for 4 min in canola oil and their post‐fry quality changes at room environment (RE, 25°C) and under IR‐heating (65 °C) were investigated. Results showed that in addition to moisture‐fat profile, batter coating substantially (P < 0.05) influenced the development of thermal, textural, colour and microstructural traits of MA. Post‐fry colour changes (ΔE value: 3.1 to 10.4) in MA‐based coated product continued under IR‐heating (65 °C). Evolution of the thermal, textural and colour attributes of MA‐based coated products were significantly (P < 0.05) influenced by the formulation of outer batter coatings. Moisture migration occurred from high moisture (ranged from 1.07 to 1.25 g g−1 dry matter) containing core to dry (moisture ranged from 0.15 to 0.59 g g−1 dry matter) crust region of MA‐based coated fried product, where the moisture migration was interlaced with batter formulations. Holding environment and duration substantially (P < 0.05) impacted the textural properties (hardness, brittleness and crispiness) of MA‐based coated fried product. Glass transition temperature (Tg) of coated fried products were ranged between −20.4 to −23.0 °C, that explains quality changes at RE and under IR‐heating. Scanning electron microscopic image analysis (surface openings: 5.7 to 27.31%; fractal dimension: 2.555 to 2.702) revealed the impact of surface microstructure and mass‐transfer modulated textural development in MA‐based coated products. FTIR spectroscopy revealed surface chemical profile in relation to colour evolution of MA‐based fried products. Principal component analysis outcome (PC1: 52.9.% and PC2: 25.8%) revealed varying extent of correlation between studied thermomechanical and physicochemical attributes.