Transmission Electron Microscopy Images Research Articles

Combining Machine Learning Algorithms with Traditional Methods for Resolving the Atomic-Scale Dynamic Structure Reconstruction of Monolayer MoS2 in High-Resolution Transmission Electron Microscopy

Abstract High-resolution transmission electron microscopy promises rapid atomic-scale dynamic structure imaging. Yet, the precision limitations of aberration parameters and the challenge of eliminating aberrations in Cs-corrected transmission electron microscopy constrain resolution. A machine learning algorithm is developed to determine the aberration parameters with higher precision from small, lattice-periodic crystal images. The proposed algorithm is then validated with simulated HRTEM images of graphene and applied to the experimental images of a molybdenum disulfide (MoS2) monolayer with 25 variables (14 aberrations) resolved in wide ranges. Using these measured parameters, the phases of the exit-wave functions are reconstructed for each image in a focal series of MoS2 monolayers. The images were acquired due to the unexpected movement of the specimen holder. Four-dimensional data extraction reveals time-varying atomic structures and ripple. In particular, the atomic evolution of the sulfur-vacancy point and line defects, as well as the edge structure near the amorphous, are visualized as the resolution has been improved from about 1.75 Å to 0.90 Å. This method can help salvage important transmission electron microscope images and is beneficial for the images obtained from electron microscopes with average stability.

Ultrasmall Bismuth Nanoparticles Supported Over Nitrogen-Rich Porous Triazine-Piperazine Polymer for Efficient Catalytic Reduction.

The development of inexpensive and reusable nanocatalysts to convert the hazardous pollutant 4-nitrophenol (4-NP) into a valuable platform chemical 4-aminophenol (4-AP) is quite demanding due to environmental and public health concerns. Herein, we report a facile strategy for the preparation of supported Bi nanoparticles (NPs) over the surfaces of nitrogen-rich porous covalent triazine-piperazine-3D nanoflowers (BiNPs@3D-NCTP). SEM and TEM image analysis suggested 3D-flower-like morphology of the materials. The powder X-ray diffraction (PXRD) analysis also confirmed the loading of Bi NPs. N2 sorption analysis suggested BET surface areas of 663 and 364 m2g-1 for the 3D-NCTP and BiNPs@3D-NCTP materials, respectively. The large surface area, bimodal pores and 3D nanoflower architecture enable uniform loading of Bi nanoparticles, while its nitrogen-rich functionality stabilizes and acts as a capping agent restricting further nanoparticle expansion. BiNPs@3D-NCTP showed a 99.85% conversion for the 4-NP to 4-AP within four minutes. The normalized rate constant of 38.3 min-1 mg-1 of BiNPs@3D-NCTP catalyst for reducing of 4-NP suggested its superior catalytic efficiency. Nitrogen-rich functionality activates the catalytic site to accelerate the reaction, while bimodal pores can promote diffusion of reactant molecules. After five catalytic cycles, the nanocatalyst showed high chemical stability and negligible activity loss.

Effect of ball milling on bulk MoS2 and the development of Al–MoS2 nanocomposites by powder metallurgy route

Abstract The present study provides an in-depth investigation of the exfoliation of molybdenum disulfide (MoS2) using high-energy ball milling and the subsequent development of aluminum‒molybdenum disulfide (Al–MoS2) nanocomposites via a powder metallurgy (PM) route. X-ray diffraction confirmed that the commercially available bulk MoS2 did not develop new phases after intense ball milling for up to 30 h. The effects of ball milling on the thermal stability and morphological changes in MoS2 powder have also been reported. The milling action caused a shift in the band gap of MoS2, from 1.2 to 1.44 eV due to quantum confinement phenomena confirmed by UV–visible absorption spectroscopy. The impacts of ball milling on the specific surface area and mean pore diameter of MoS2 were determined by the Brunauer–Emmett–Teller surface area analysis technique. Additionally, the investigation through Fourier transform infrared spectroscopy verifies the presence of functional groups, such as hydroxyl (O–H), alkane (C–H), and ether (C–O), on the MoS2 surface. The milling resulted in a significant reduction in particle size from an initial mean size of 1.2 µm–480 nm. Field emission scanning electron microscopy micrographs of the exfoliated MoS2 revealed a thin, cracked, and flake-like morphology. High-resolution transmission electron microscopy images revealed that the high-energy ball milling resulted in few-layered MoS2 nanoplatelets after 30 h of ball milling. Subsequently, the investigation extended its focus to the development of Al–MoS2 nanocomposites using the PM route, incorporating MoS2 into the Al matrix at different weight percentages (1, 2, 3, and 5 wt.%). Al-5 wt.% MoS2 nanocomposite showed the highest relative density of 93.09 %, the maximum hardness of 743.6 MPa, and the best wear performance among all the Al–MoS2 nanocomposites. The hardness of Al-5 wt.% MoS2 nanocomposite was 109.11 % higher than that of the pure Al sample developed similarly. A maximum compressive strength (σ max) of 494.67 MPa was observed in Al-5 wt.% MoS2 nanocomposite, which was 1.84 times the value of σ max obtained from sintered pure Al sample.

Fabrication of ZnIn2S4/CeO2 S-scheme heterojuntion for the enhanced removal of tetracycline under visible light irradiation

A series of S-scheme ZnIn2S4/x-CeO2 heterojunction were designed and fabricated through in-situ precipitation and hydrothermal method. XRD, SEM, TEM, EDX, XPS, UV-vis DRS and adsorption-photocatalytic techniques were employed to investigate its crystal phase structure, morphology, size, elemental composition, photo-response property and elimination ability for tetracycline. XRD analysis revealed CeO2 and ZnIn2S4 in ZnIn2S4/x-CeO2 sample presented cubic and hexagonal phase structure, respectively. SEM and TEM images indicated that CeO2 particles with irregular-shaped of around 20nm were attached on the smooth surface of ZnIn2S4 microparticles with ca. 4 μm. All the as-synthesized ZnIn2S4/x-CeO2 samples could harvest more visible-light and the absorption edges were red-shifted in comparison with pure CeO2. ZnIn2S4/0.3-CeO2 sample exhibited remarkably enhanced photocatalytic performance and its removal efficiency for tetracycline reached 87.29% within 100min. The detailed experimental and DFT calculation indicated that the enhanced photocatalytic property was mainly ascribed to the synergistic effect of wide light-response range, suitable band position and successful fabrication of S-scheme heterostructure, which was in favor of rapid transfer and available separation of photo-generated e-/h+ pairs. The scavenger experiments and the ESR data revealed that the •O2– and h+ active species played the dominant role in tetracycline removal over ZnIn2S4/0.3-CeO2 system. In addition, the as-synthesized ZnIn2S4/0.3-CeO2 samples had excellent stability and the removal efficiency still reached 70.73% after being repeatedly used for 4 times. Furthermore, the possible enhanced photocatalytic mechanism over ZnIn2S4/x-CeO2 was proposed to get a better understanding of photocatalytic process. This work provided the guidance to fabricate CeO2-based heterojunction with promising prospect for the efficient elimination of antibiotic residues from wastewater.

Unveiling the role of sintering temperatures in the physical properties of Cu-Mg ferrite nanoparticles for photocatalytic application

This research presents an explicit analysis of the effects of sintering temperature (Ts) on the structural, morphological, magnetic, and optical properties of Cu0.5Mg0.5Fe2O4 nanoferrites synthesized via the sol-gel method. To accomplish it, Cu-Mg ferrite NPs were sintered at temperatures ranging from 300 to 800 °C in increments of 100 with a constant holding duration of 5 h. Thermogravimetric analysis was used to observe the degradation of organic components and the thermally stable zone of the material. XRD analysis and SAED patterns revealed the formation of a single face-centred cubic (fcc) spinel structure with an Fd–3m space group. The particle's crystallite sizes have grown from 4.54 to 102.54 nm as Ts have increased, consistent with TEM results. Further evidence for the creation of spinel structure was provided by two prominent absorption bands in FTIR spectroscopy below 1000 cm−1. The particles were found to have a densely packed, nearly spherical morphology, as confirmed by TEM images. The EDS was utilized to identify the chemical species that were present in the sample. A significant correlation was observed between particle size and magnetic properties. The field-dependent magnetization investigations revealed that particles with crystallite sizes of 4.54 and 5.10 nm were superparamagnetic, while those measuring 11.68, 23.81, 42.95, and 102.54 nm exhibited ferrimagnetic characteristics. Furthermore, it was revealed that an increase in sintering temperature results in a concurrent amplification of crystallites, which subsequently heightens the saturation magnetization of the prepared NPs from 9.49 to 33.04 emu/g. The coercivity value clarifies the sintering effect of transforming the particle from a single-domain to a multi-domain magnetic state. The finite-size scaling formula precisely characterizes the changes in Curie temperature. In addition, the semiconducting characteristics of Cu-Mg ferrite NPs were confirmed through DRS, which unfolded an optical band gap within the range of 1.84–2.26 eV. The Mulliken electronegativity approach unveiled the prospective efficacy of these NPs in photocatalytically generating O2 from water. Cu-Mg nanoferrites exhibit a favourable bandgap and potential as a photocatalyst, rendering them a potentially fruitful addition to the family of ferrite materials utilized in photocatalytic and associated solar energy applications.

Staged evolutionary features of the aromatic structure in high volatile A bituminous coal (hvAb) during gold tube pyrolysis experiments

Low-temperature pyrolysis of coal is a crucial step in the coal thermal conversion process and involves very complex physical and chemical reactions that can have different effects on the coal's structure. The thermal evolution behavior and transformation mechanism of the coal microstructure are not yet fully understood, which also limits the efficient utilization of coal to a certain extent. The aromatic structural features (including size, molecular ordering, nematic symmetry, stacking, and curvature) of the char produced from low-temperature pyrolysis of high volatile A bituminous coal (hvAb) from the Xutuan coal mine, China, were quantitatively assessed via high-resolution transmission electron microscopy (HRTEM) image processing and analytical techniques. The thermal transformation process and the mechanisms controlling it were explored. The results show that, except for the unexpected slight growth of aromatic sheets at 440 °C, the lower pyrolysis temperature (< 521 °C) contributed weakly to their size growth, whereas at higher temperatures (561–600 °C), it significantly increased their size. The aromatic molecular ordering tended to gradually change in three stages: increasing between 340 and 440 °C, decreasing between 440 and 521 °C and increasing again between 521 and 600 °C. The nematic symmetry strength of aromatic fringes also followed a similar pattern with temperature at different scales. Additionally, in addition to a very minor development trend at 440 °C, the stacking did not significantly change at temperatures below 521 °C but developed appreciably further with increasing temperatures at 561–600 °C; however, the average spacing of the stacks did not appear to be significantly reduced at all temperatures. The curvature of the aromatic sheets also varied in different temperature stages, i.e., initially slightly increasing (340–380 °C), then gradually decreasing (380–480 °C), later increasing again (480–521 °C), and eventually decreasing (521–600 °C). The properties of the chemical composition and structure of the initial coal play important roles in the thermal reaction behavior, and the physical and chemical reactions that dominate at the different temperature stages may be responsible for such wiggly trends in the evolution of the aromatic structure. Notably, the properties of the mesophase (approximately 440 °C) strongly influence the subsequent structural transformation. These findings could provide useful information for the microstructure–property relationships and preparation of coal-based carbon materials.

SnO2-TiO2/reduced graphene oxide nanocomposites: Green synthesis and enhanced photocatalytic efficiency for dye removal

Titanium oxide nanoparticles (TiO2 NPs) have been interested in potential applications, including gas-sensing, energy storage, environmental remediation, and medical fields. In the present work, fabricated SnO2-TiO2/RGO nanocomposites (NCs) have been produced through a green precipitation approach. XRD, TEM, SEM, EDX, XPS, FTIR, UV, and PL analyses have been carefully applied to invistage the physicochemical properties of prepared NPs and NCs. The XRD data showed that the crystal structure of the TiO2 NPs was affected by the introduction of SnO2 NPs and RGO sheets. The spherical shape of the prepared samples and their morphologies were confirmed using TEM and SEM images. EDX and XPS analyses confirmed that tin (Sn), titanium (Ti), oxygen (O), and carbon (C) were further present in the SnO2-TiO2/RGO NCs. FT-IR spectra determines the functional groups with bands between the compositions of obtained NPs and NCs. Besides, the band gap energies of prepares samples were estimated from UV–vis spectra. It displayed that the absorption peak of the synthesized TiO2 NPs was improved after the addition of SnO2 NPs and an RGO sheet. PL analysis indicate that the PL intensity of the prepared TiO2 NPs was decreased with the addition of SnO2 NPs and RGO sheets due to a decrease in the recombination rate of electrons (e−)-holes (h+). As shown in photocatalytic results, the photodegradation of methylene blue (MB) dye of SnO2-TiO2/RGO NCs was reached 92.20% after 140 min of UV irradiation. These results suggest that the addition of RGO sheets occupied a role in enhanced the photocatalytic performance of the prepared NCs. This study highlighted that these samples could be applied in various applications such as photocatalytic and therapeutic areas.

Rapid photocatalytic degradation of selective organic dyes using metal oxide-metal sulphide and its inverted nanocomposites

The chemical precipitation approach was employed to synthesize novel heterostructures, namely CeO2-ZnS and SnO2-ZnS, along with inverted nanocomposites ZnS-CeO2 and ZnS-SnO2. The nanocomposites were subjected to characterization using various techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV–Vis absorption spectra, and photoluminescence spectra. The TEM images demonstrated particles that were homogeneous, well-dispersed, and comparatively tiny with a sphere-like structure. This indicates successful synthesis and desirable morphological properties of the nanocomposites. The integration of varied nanoparticles within a heterostructure commonly gives rise to synergistic effects, imparting superior properties to the composite compared to the individual components. These nanocomposites tested for their photocatalytic degradation efficiency using Rose Bengal (RB) and Crystal Violet (CV) dyes under natural sunlight and they exhibited approximately 95 % degradation rate. The degradation results demonstrated a significant enhancement in the photocatalytic efficiency of ZnS-CeO2 and CeO2-ZnS nanocomposites. This improvement was attributed to the effective recombination suppression of photogenerated electron-hole pairs, leading to the generation of highly reactive free radicals. The first-order kinetic rate constant for CeO2-ZnS was determined to be 0.52 min−1 for CV and 0.53 min−1 for RB. The present research work has the potential to offer a novel approach to the construction of new heterojunction photocatalysts and to provide a more profound understanding of the treatment of textile organic dyes.

Preparation, characterization, and structural studies of methylcellulose/CuO hybrid materials

Flexible hybrid materials composites of methylcellulose (MC) and CuO are fabricated successfully with solution-casting preparation method as confirmed by the energy-dispersive X-ray spectroscopy (EDX), transmission electron microscope (TEM), and Fourier transform infrared methods. The EDX of MC/CuO recorded the peaks of C, O, and Cu with percentage ratios of 49.61%, 47.35%, and 3.04%, which verify the appropriate formation of the MC/CuO. The TEM image shows that the size of CuO is from 11 to 51 nm. The images from the SEM also show that the CuO nanoparticles are evenly distributed throughout the MC/CuO composite. The impact of CuO on MC transparency is also investigated via UV/vis spectroscopy. The optical parameters of the polymer and composites films were recorded. The bandgap energy of MC is reduced from 4.83 to 4.69, 4.33, and 4.2 eV when mixed with 1.5%, 3%, and 4.5% CuO, respectively, while the band tail is increased from 1.6 to 2.93, 3.66, and 4.15 eV. Carbon cluster numbers also rise from 50 for MC to 54, 63, and 67 for the addition of CuO concentrations of 1.5%, 3%, and 4.5%, respectively. The purpose of this work is fabrication of new nanocomposite materials with innovative flexible properties that may find application in high-performance optoelectronics.

Azelaic acid-based lyotropic liquid crystals gel for acne vulgaris: Formulation optimization, antimicrobial activity and dermatopharmacokinetic study

The proposed study aimed to develop a topical gel containing azelaic acid (AZA)-based lyotropic liquid crystals (LLCs) for the treatment of acne vulgaris. AZA-based LLCs were optimized by varying Poloxamer-407 and polyvinyl alcohol concentration using a central composite design, which showed that both independent variables had a significant effect on the formulation. The highest desirable trial of AZA-based LLCs (Batch-7) containing 300 mg poloxamer-407 and 100 mg polyvinyl alcohol depicted the particle size, zeta potential, and entrapment efficiency of 184.2 nm, −16.1 mV, and 79.96 %, respectively. TEM images confirmed the globular vesicles of LLCs, and ATR-FTIR and DSC results confirmed the compatibility of formulation excipients. In vitro, the release of AZA, AZA-based LLCs, AZA-based LLC gel, and marketed gel showed a release of 23.29, 95.24, 91.07 and 59.88 %, respectively, after 24 h in phosphate buffer pH 6.8. Ex vivo release of AZA-based LLC gel displayed an 86.56 % release after 24 h. The antimicrobial activity of AZA-based LLC gel exhibited a comparable efficacy with marketed gel against Cutibacterium acnes, Staphylococcus epidermis and Staphylococcus aureus. The acute dermal irritation study indicated excellent safety and skin compatibility of AZA-based LLC gel without any erythema and edema. The dermatopharmacokinetic study displayed an enhanced drug retention for AZA-based LLC gel (146.121 ± 21.13 µg/cm2) than marketed gel (58.58 ± 15.95 µg/cm2) in the dermal layer, which would improve its therapeutic effect. These outcomes proved that AZA-based LLC gel has the potential to enhance skin penetration and retention for effective management of acne vulgaris.

Formulation and evaluation of anti-rheumatoid arthritis effects of Ag nanoparticles containing Allium sativum L. Leaf extract

Rheumatoid arthritis is a persistent inflammatory disorder that typically impacts individuals aged 20 to 40. It is characterized by inflammation of the synovial membrane, degradation of cartilage, and joint pain among its various symptoms. Researchers have recently developed, analyzed, and altered biomarkers and nanomaterials that are frequently employed to improve the diagnostic and therapeutic approaches for rheumatoid arthritis. Here, we have created and formulated a novel therapeutic agent that incorporates silver nanoparticles@Allium sativum L. leaves to treat arthritis. The characterization of silver nanoparticles (AgNPs) was performed utilizing various techniques. The FE-SEM and TEM images demonstrated that the majority of these nanoparticles exhibited a spherical shape (10 to 50 nm). Additionally, a notable peak at a wavelength of 403 nm in the UV–Vis spectrum confirmed the successful formulation of the Ag NPs. The antioxidant assay revealed that the IC50 values for the silver nanoparticles@Allium sativum L. and BHT in relation to DPPH were 21 and 44 µg/mL, respectively. In vivo assessments were performed utilizing models involving formaldehyde, CFA, and turpentine oil at various dosage levels. Silver nanoparticles@Allium sativum L. exhibited anti-arthritic properties with the most significant potential observed at 1 mg/kg. Data from the CFA model revealed a more substantial protective effect on arthritic lesions and alterations in body weight. The recent results indicates the recovery of rheumatoid arthritis criteria including synovial cavity swelling and edema inhibition percentage in turpentine test, paw diameter in CFA test and paw edema in formaldehyde test. In conclusion, these data support the administration of silver nanoparticles as potent therapeutic agents for rheumatoid arthritis treatment in humans.

Salvia sclarea L. (Clary Sage) Flower Extract-Mediated Green Synthesis of Silver Nanoparticles and Their Characterization, Antibacterial, Antifungal, and Scolicidal Activities against Echinococcus granulosus

Over the past few decades, nanoscience has gained a prominent position in plant-mediated synthesis of nanoparticles due to its advantages, such as environment-friendly and practical nature and biological safety and compatibility. This study was conducted to develop silver nanoparticles (NPs) based on Salvia sclarea flower extract and characterize them using UV-visible spectroscopy, Dynamic Light Scattering, Zeta potential analysis, Fourier Transform Infrared Spectroscopy, X-ray diffraction, Field Emission Scanning Electron Microscopy, and Transmission electron microscopy. We also evaluated the antibacterial (4 standard bacterial strains), anti-Candida (40 clinical isolates), and scolicidal activities of the green-synthesized Ag NPs. The characteristic absorption peak at 440nm indicated the successful synthesis of AgNPs with spherical morphology and a size range of 30-40nm according to TEM imaging. The FT-IR spectrum revealed the presence of functional constituents such as phenols, terpenoids, and saponins in the flower extract that could reduce metal ions and form AgNPs. EDX analysis confirmed the presence of silver (91.3%) in the synthesized NPs. In addition, AgNPs exhibited remarkable antimicrobial activity. The highest antibacterial and antifungal activities of AgNPs were observed against Bacillus cereus and Candida krusei, respectively, while the lowest activities were observed against Pseudomonas aeruginosa and Candida albicans. At the concentration of 320μg/mL, AgNPs delivered the highest percentage of mortality (100%) against liver hydatid cyst protoscoleces within 15minutes. Our findings highlight the potential of S. sclarea extract as an inexpensive and readily available material for producing biogenic AgNPs with versatile applications.

Predicting column heights and elemental composition in experimental transmission electron microscopy images of high-entropy oxides using deep learning

A novel approach is presented by integrating images-driven deep learning (DL) with high entropy oxides (HEOs) analysis. A fully convolutional neural network (FCN) is used to interpret experimental scanning transmission electron microscopy (STEM) images of HEO of various sizes. The FCN model is designed to predict column heights (CHs) and elemental distributions from single, experimentally acquired STEM images of complex (Mn, Fe, Ni, Cu, Zn)3O4 HEO nanoparticles (NPs) at atomic resolution. The model’s ability to predict elemental distributions was tested across various crystallographic zones. It was found that the model could effectively adapt to different atomic configurations and operational conditions. One of the significant outcomes was the identification of substantial elemental inhomogeneities in all experimental NPs, which highlighted the random and complex nature of element distribution within HEOs. The developed FCN DL method can be applied to assist experimental HEO and beyond NP analysis in various operating conditions.

Green Synthesis, Characterization and Antimicrobial Activities of Silver Nanoparticles against some Phypathogenic Bacteria

Green chemistry methods are now an intriguing field of study in agriculture, particularly in pest management. For this reason, novel approaches for the more efficient manufacturing of nanoparticles with improved biological characteristics have been developed. Because nanoparticle production is faster, this method is more eco-friendly and less toxic than old methods. The biosynthesis of silver nanoparticles (AgNPs) using Leucaena leucocephala, Mentha aquatica, and Zingiber officinale extracts and their antibacterial activity against Pectobacterium cartovorum, Agrobacterium tumefaciens, and Xanthomonas axonopodis. The results showed that spectroscopic and microscopic methods, such as UV-Vis spectroscopy, revealed absorption peaks for Ll-AgNPs at 415 nm, 420 nm for Ma-AgNPs, and 430 nm for Zo-AgNPs, indicating the silver nature of the prepared colloidal samples. The TEM images revealed the quasi-spherical morphology of NPs with an average size of 12.51, 10.63, and 10.26 nm for Ll-AgNPs, Ma-AgNPs, and Zo-AgNPs. The X-ray diffraction (XRD) pattern revealed a face-centered cubic (FCC) structure with crystallite. While distinctive peaks in an investigation using Fourier transform infrared (FT-IR) spectroscopy showed that several biomolecules were attached to AgNPs, antibacterial activity was evaluated by an inhibitory zone test, which showed high efficiency against P. cartovorum, A. tumefaciens, and X. axonopodis, with an antibacterial function comparable to L. leucocephala, M. aquatica, and Z. officinale extract. The green production of silver nanoparticles has the potential to be a useful tool in pest management strategies against phytopathogenic bacteria.

Assessment of the Biocontrol Efficacy of Silver Nanoparticles Synthesized by Trichoderma asperellum Against Infected Hordeum vulgare L. Germination

This study investigated the biosynthesis, statistical optimization, characterization, and biocontrol activity of silver nanoparticles (AgNPs) produced by newly isolated Trichoderma sp. The Trichoderma asperellum strain TA-3N was identified based on the ITS gene sequence, together with its phenotypic characteristics (GenBank accession number: OM321439). The color change from light yellow to brown after the incubation period indicates AgNPs biosynthesis. The UV spectrum revealed a single peak with the maximum absorption at 453 nm, indicating that T. asperellum produces AgNPs effectively. A Rotatable Central Composite Design (RCCD) was used to optimize the biosynthesis of AgNPs using the aqueous mycelial-free filtrate of T. asperellum. The optimal conditions for maximum AgNPs biosynthesis (156.02 µg/mL) were predicted theoretically using the desirability function tool and verified experimentally. The highest biosynthetic produced AgNPs by T. asperellum reached 160.3 µg/mL using AgNO3 concentration of 2 mM/mL, initial pH level of 6, incubation time of 60 h, and biomass weight of 6 g/100 mL water. SEM and TEM imaging revealed uniform spherical shape particles that varied in size between 8.17 and 17.74 nm. The synthesized AgNPs have a Zeta potential value of −9.51 mV. FTIR analysis provided insights into the surface composition of AgNPs, identifying various functional groups such as N–H, -OH, C-H, C=O, and the amide I bond in proteins. Cytotoxicity and genotoxicity assays demonstrated that AgNPs in combination with T. asperellum can mitigate the toxic effects of Fusarium oxysporum on barley. This intervention markedly enhanced cell division rates and decreased chromosomal irregularities. The results indicate that AgNPs synthesized by T. asperellum show the potential as an eco-friendly and efficient method for controlling plant diseases. Further studies are necessary to investigate their possible use in the agricultural sector.

Inquisition on enhanced photocatalytic performance of ternary cerium manganese nickel metal oxide nanocomposites

The hydrothermal approach was used to successfully incorporate ternary Cerium Manganese Nickel mixed metal oxides (CMN-MMOs) with various Ce/Mn/Ni ratios. The improved crystallanity of incorporated CMN-MMOs was discovered using powder X-ray diffraction. From Ultra Violet (UV)–visible diffuse reflection spectroscopy (DRS), CMN-MMOs displays a broad absorption in the visible range. Scanning Electron Microscope (SEM) reveals that CMN-MMOs exhibit in nanoslab. Image of Transmission Electron Microscope (TEM) expose that synthesized samples are in hexagonal structure with average size of 20–30 nm. The photocatalytic activity was appraised for calcined samples of CMN-MMOs (1: 1: 2). It indicates the greatest photocatalysic activity with 89 % degradation of methylene blue (MB) dye. CMN- MMOs (1: 1: 2) also had a strong degradation effect on the non-dye contaminant phenol. Methylene Blue degradation followed a pseudo-first-order kinetic trend. The mechanism of photo degradation of CMN- MMOs was also explored.

Facile synthesis of CoFe2O4 and CoxNi1−xFe2O4 nanoparticles substituted in MoS2 nanosheets for photothermal/chemo therapy application

Cancer and its treatment have been one of the challenges of humans since the beginning, and much research has been conducted over many years on its treatment methods. In recent years, the use of new and low-complication methods, as well as combined methods, has become increasingly widespread. This study investigated the combined process of photothermal and chemotherapy for nanocomposite CoxNi1−xFe2O4∕MoS2. For this purpose, nanocomposite has been synthesized using a facile sol-gel and hydrothermal method. The structure and shape of nanostructures have been investigated using X-ray diffraction patterns, scanning electron microscopes, and transmission electron microscope images. The results confirmed the formation of CoxNi1−xFe2O4 nanoparticles with an approximate size of 55.44 nm, substituted in nanosheets MoS2. The results of UV–visible adsorption show that the synthesized nanocomposites have band gaps of 1.65 eV and 1.48 eV for nanostructures CoFe2O4∕MoS2 and Co0.5Ni0.5Fe2O4∕MoS2, respectively. Also, the photothermal efficiency of nanocomposites CoFe2O4∕MoS2 and Co0.5Ni0.5Fe2O4∕MoS2 irradiated with 808 nm diode laser and 1-watt power density are 31 % and 26 %, respectively. The loading rate of doxorubicin drug in nanocomposite is ∼ 60 %.

Scanning transmission electron tomography to study virus assembly: Review for the retirement of Paul Walther.

In this short and popular review, we summarise some of our findings analysing the replication cycles of large DNA viruses using scanning transmission electron tomography (STEM tomography) that we applied in the laboratory of Paul Walther. It is also a tribute to a very kind and expert scientist, who recently retired. Transmission electron microscopy (TEM), in particular cryo-EM, has benefited tremendously from recent developments in instrumentation. However, TEM imaging remains limited by the thickness of the specimen and classical thin-section TEM typically generates 2D representations of 3D volumes. Although TEM tomography can partly overcome this limitation, the thickness of the sample, the volume that can be analysed in 3D, remains limiting. STEM tomography can partly overcome this problem, as it allows for the analysis of thicker samples, up to 1 µm in thickness. As such, it is an interesting imaging technique to analyse large DNA viruses, some of which measure 1 µm or more, and which is the focus of our research interest.

Template-free synthesis of hollow titanium dioxide microspheres and amorphous titanium dioxide microspheres with superior lithium and sodium storage performance

Hierarchical hollow TiO2 microspheres (H-TiO2) and amorphous solid TiO2 microspheres (A-TiO2) were synthesized using a template-free method. Initially, quasi-monodisperse solid TiO2 microspheres (A-TiO2) were obtained by controlled thermal hydrolysis of titanium sulfate, forming aggregates of amorphous particles, followed by solvothermal treatment to convert the solid structure into a hollow and crystalline H-TiO2 structure. SEM and TEM images revealed that the morphological evolution from A-TiO2 to H-TiO2 conforms precisely to the inside-out Ostwald ripening mechanism. The unique hollow layered structure endows H-TiO2 with a large specific surface area of 93.3 m2/g and a rich porous structure. When used as an anode material for LIBs and SIBs, H-TiO2 exhibits superior cycling stability and rate performance compared to A-TiO2. For LIBs, H-TiO2 achieves a reversible capacity of 342.2 mA h g−1 at a 0.2C charge/discharge rate and retains unprecedented long-term stability at high current densities (258.5 mA h g−1 after 1000 cycles at 5C and 220.4 mA h g−1 after 1000 cycles at 10C). For SIBs, H-TiO2 exhibits a reversible capacity of 271.7 mA h g−1 at 0.2C, with specific capacities of 173.4 mA h g−1 after 1000 cycles at 1C and 101.4 mA h g−1 after 2000 cycles at 5C. Furthermore, kinetic calculations demonstrate that H-TiO2 possesses higher Li+ and Na+ diffusion rates, adsorption capacities, and conductivity, further explaining its excellent electrochemical performance.

Panax ginseng nanoemulsion for counteracting male infertility via modulating sex hormones and oxidative stress in a rat model

This study end to develop nanoemulsions of Panax ginseng dry extract and to evaluate the potential impact of these nanoemulsions versus free Panax ginseng dry extract and Vit.E in recovering male infertility induced in rats. Nanoemulsions of Panax ginseng dry extract were prepared by oil in water method. The designed samples were characterized by TEM, zeta sizer, FTIR, and TGA. The in vitro study included DPPH assay to estimate the free radical scavenging activity of the suggested treatments. The in vivo study included 100 adult male Wistar rats which were assigned into 10 equal groups; five groups of young rats weighting (150–200 g) and five groups of aged rats weighting (350–400 g). Group I, negative control. Group II, bisphenol-A (BPA). Group III, BPA+ Panax ginseng dry extract nanoemulsion. Group IV, BPA+ free Panax ginseng dry extract. Group V, BPA +Vit.E. After 40 days, serum total testosterone, free testosterone, MDA, 8-OHdG and AGEs were estimated. Besides, the histological investigation of testicular tissue sections was performed. TEM imaging of Panax ginseng dry extract nanoemulsions indicated spherical shape with diameter range from 2 to 50 nm, and the size distribution was in the range from 62 to 123 d.nm. The zeta potential of the designed nanoemulsions was -32.8 to -38.9 mV. FTIR spectra revealed the common active groups in the prepared nanoemulsions. The thermal stability of the nanoemulsions was up to 207 ºC. The in vitro results of DPPH assay showed % inhibition of DPPH free radical for Panax ginseng nanoemulsions samples was 49.38% (for young-treated group Sample A) and 72.28% (for aged-treated group Sample B), while for free Panax ginseng dry extract samples was 30.27% (for young-treated group Sample C) and 56.76% (for aged-treated group Sample D), for Vit.E samples was 32.36% (for young-treated group Sample E) and 36.39% (for aged-treated group Sample F).Thus the nanoemulsions exhibit free radicals scavenging activity more than free Panax ginseng dry extract and Vit.E. The in vivo findings elucidated that Panax ginseng dry extract nanoemulsions and Vit.E successfully revers the progressive insult of BPA on male fertility by significantly enhance total testosterone (2.87±0.318) and free testosterone (1.63±0.033) serum levels, and significantly decrease MDA (2.77±0.018), 8-OHdG (6.76±0.174) and AGEs (92.60±1.701) serum levels. Interestingly, the most promising outcomes were recorded upon the treatment with Panax ginseng dry extract nanoemulsions. In conclusion the developed Panax ginseng dry extract nanoemulsion could be used as a promising strategy in improving potential male infertility defects by rescuing male sex hormones, neutralizing oxidative stress and retrieving the structural organization of the testes.