Scanning Electron Research Articles

Development and Evaluation of Voriconazole Loaded Transfersomal Gel for Enhanced Antifungal Activity.

The BCS class II antifungal drug voriconazole (VRC) has a broad spectrum of action. Its solubility is still a major problem for formulation scientists despite numerous attempts to improve it. The thin-film hydration technique produced the voriconazoleloaded Transfersomes, optimized using the Central Composite Design (CCD) and then included as a gel into Poloxamer 407P. Several parameters were assessed for the prepared VRCT, including particle size, zeta potential, surface shape, potential chemical interaction, and polydispersity index (PI). The SEM study also revealed the appearance and surface of optimized transferosomes are symmetrical. The optimized formulation’s average size was found to be 238.8 nm by the particle size analysis. Similarly, a value of 0.449 was found by the polydispersity index (PI). To evaluate voriconazole Transfersomal gel’s (TG4) antibacterial efficacy, an antimicrobial investigation was conducted. The creation of Transfersomal gel formulation offers a topical drug administration method that is more effective and improves patient compliance.

Impact of the Jenkyns Event on shallow-marine carbonates and coeval emerged paleoenvironments: the Plitvice Lakes region, Croatia

Early Jurassic (late Pliensbachian–early Toarcian) Large Igneous Province (LIP) magmatism affected the entire ocean-atmosphere system culminating in a cascade of paleoenvironmental perturbations known as the Jenkyns Event which globally impacted marine, transitional and terrestrial paleoenvironments. Carbonate platforms at low latitudes in the Western Tethys realm drowned or shifted to non-skeletal production during the early Toarcian due to sea level rise, global warming, and ocean acidification. Unlike deep-marine deposits, shallow-marine carbonates present a challenge in defining global geochemical signals due to common diagenetic modifications. An integrated dataset including δ13Ccarb and δ18Ocarb, TOC, biomicrofacies, SEM, XRD, and palynological study of two stratigraphic successions in the Plitvice Lakes region, Bjelopolje (BJ) and Plitvice Spring (PS), in Croatia, provides an overview of the paleoenvironmental evolution and lateral facies changes in a peritidal setting during the Early Jurassic on the Adriatic Carbonate Platform (AdCP). The investigated stratigraphic succession starts with upper Pliensbachian, peloid-ooid-bioclastic grainstones alternating with fenestral and massive mudstones overlain by lower Toarcian, lagoonal, bioturbated, “spotted” limestones with horizons indicative of short-lived subaerial emergence during the early Toarcian. A negative excursion in δ13Ccarb, foraminifer assemblages, and the predominance of Classopollis pollen within the “spotted” limestones marks the stratigraphic position of the Jenkyns Event. Global-scale events (sea level variation, climate change, C-cycle perturbation, anoxia) operated simultaneously with local to regional synsedimentary tectonics and eustatic movements that preserved the AdCP carbonate factory from collapse or drowning but resulted in pronounced facies differentiation on the shallow-marine carbonate platforms.

QBD approach for green synthesis of Rutin silver nanoparticles- screening for antioxidant, anticancer and anticlastogenic potential

Rutin is a flavonoid glycoside abundant in many plants exhibiting pharmacological activities like antioxidant, anticancer, anti-inflammatory and antimicrobial activities. Plant biomarkers suffer low bioavailability and solubility that lack clinical effectiveness. The smart nanoparticles conversion addresses this limitation with optimal particle size and targeted drug delivery. The present study involves QbD approach for formulation of Rutin silver nanoparticles and evaluation of antioxidant, anticancer and anticlastogenic potential. QbD experimentation involved particle size and drug release as dependent variables over the silver nitrate concentration, methanol and sonication time as independent variables devising 15 formulations (F1 –F15). F12 formulation was found to be optimized with 126.3 nm average size, stable and dispersible characterized by UV, FTIR, SEM and DLS studies. The calibration curve of Rutin was plotted at 352 nm with linearity (LOD = 0.061 μg/ml and LOQ = 0.187 μg/ml). The invitro drug release studies by USP dissolution apparatus I (Basket type) proved the sustained release characteristics with 97.3 % drug release when compared to the Rutin. The pharmacological screening for potential antioxidant and anticancer activity on G361 and MCF 7 cell line of F12 formulation have shown promising results and also enhanced solubility in water compared to Rutin. Anticalstogenic potential as a function of induced micronuclei frequency was evaluated as a characteristic feature in bone marrow cells obtained from mice. Results indicate pre-treatment with the F12 reduced frequency of micronuclei in mouse bone marrow cells caused by Cyclophosphamide (CP) significantly. The protective effect of F12 in suppression was demonstrated at both dosages of 100 and 200 mg/kg. Thus the findings suggest the novel Rutin silver nanoparticles as lead drug serving as antioxidant, anticancer and anticlastogenic agent.

Two stucco sculptures from the “Salone d’Ercole” in the Racconigi Castle (Cuneo, Italy): a case study

Non-invasive and micro-destructive diagnostic investigations were employed for the study of two stucco statues depicting Putti, from the “Salone d’Ercole” in the Racconigi Castle (Cuneo, Italy). The research made it possible to understand the construction technique, constituent materials, and the state of conservation of the statues. This information was useful for placing the artworks in the correct historical-artistic context and for conservation choices and restoration interventions. Different analytical investigations were applied, specifically: a) the internal metal structure was analyzed by cover meter relief combined with digital radiographic technique; b) the stucco composition and its stratigraphy were characterized by Polarized Optical Microscopy (POM), X-ray diffraction (XRD) and Electron Scanning Microscopy coupled with Energy-Dispersive X-ray spectroscopy (SEM-EDX); c) finally, the presence of organic compounds was observed by UV-Induced Visible Fluorescence (UVL) and then characterized by Fourier Transform Infrared Spectroscopy (FT-IR) analyses. The results show that the stucco Putti were made with the techniques and raw materials widely used by Ticino artists and plasterers' workshops active between the 16th and 17th centuries, in the current Canton Ticino region. As regards the state of conservation, decay phenomena such as exfoliation and loss of material were mainly attributable to the presence of epsomite.

Monitoring of suspended matter in the Dnipro River within Zaporizhzhia city, the main trends of 2022

The article presents the results of monitoring observations on the temporal distribution of the qualitative and quantitative components of the Dnipro River suspended matter within Zaporizhzhia city. The research on the territory of this powerful industrial center of Ukraine with a developed metallurgical complex was carried out from 2015 up to 2019 and from the end of 2021 to the present time. The main task of the research was determining the distribution of iron and a group of heavy metals of anthropogenic origin in the composition of the river suspension, and identifying the connections of their concentrations and forms with the natural conditions of the region. Sedimentary matter from the water flows of Dnipro River within research area was sampled once per month using sedimentary traps developed by authors. The methods of electron microscopy (with microprobe analysis) and laser diffraction analysis were used to study the suspension granulometric and chemical composition in the Center for Shared Use of Scientific Equipment of the IGS NASU. SEM studies were carried using scanning electron microscope SEM JEOL-6490 LV (Jeol Ltd., Japan) with an energy dispersive spectrometer of the X-ray microanalysis system INCA Energy+ (Oxford Instruments plc., Great Britain). Particle size analysis was determined using the laser particle size analyzer Mastersizer 2000 with a Hydro 2000S wet dispersion module (Malvern Ins. Ltd, UK).The study results of the samples taken in the first year of hostilities in Ukraine revealed a number of features which were not observed in the previous series of studies. Those peculiarities are the following ones: reduction in the intensity of sedimentary matter accumulation; decrease of technogenic components in the suspension content (in particular, the amount of ferrous metals, changes in the ratio of condensed and dispersed iron particles of silt size, as well as the component composition of fragments of alloys of non-ferrous and ferrous metals). The obtained results may indicate the sensitivity of the component composition of the suspension to changes in the external environment in general, as well as the significant impact of the anthropogenic component on the distribution of iron in suspended matter.

Phyto-toxicological effect of fipronil to plant seedlings: Assessing germination attributes, root-tip morphology, oxidative stress, and cellular respiration indices

Pesticides including insecticides are applied in agricultural practices to control insect pests. However, their excessive usage often poses a severe threat to the growth, physiology, and biochemistry of plants. Here, responses of chickpea and greengram seedlings exposed to three fipronil (FIP) concentrations i. e. 100 (1×), 200 (2×) and 300 (3×) μg mL−1 was evaluated under in vitro. Among doses, 3× had a greater negative impact on germination attributes, root-shoot elongation, vigor indices, length ratios, and survival of seedlings. Besides, the morphological distortion in root tips, oxidative stress generation, and cellular death in fipronil-supplemented root seedlings were observed under scanning electron (SEM) and confocal laser scanning (CLSM), respectively. A significant (p ≤ 0.05) and pronounced upsurge in plant stressor metabolites such as proline, malondialdehyde (MDA), electrolyte leakage (EL), hydrogen peroxide (H2O2) content, and antioxidants enzymes in plant seedlings further confirmed the fipronil toxicity. In addition, a concentration-dependent decrease in respiration efficiency (RE) and ATP content in FIP-treated seedlings was observed. Reduced mitotic index (MI) and numerous chromosomal anomalies (CAs) in root meristematic cells of seedlings are a clear indication of insecticide-induced cytotoxicity. Furthermore, a dose-dependent increase in DNA damage in root meristematic cells of greengram revealed the genotoxic potential of fipronil. Conclusively, fipronil suggested phyto and cyto-genotoxic effects that emphasize their careful monitoring in soils before application and their optimum addition in soil-plant systems. It is high time to prepare both target-specific and slow-released agrochemical formulations for crop protection with concurrent safeguarding of the soil.

Two new species of Torunotum Hosseini & Cassis 2019 (Hemiptera: Miridae: Deraeocorinae: Hyaliodini) from New Caledonia

Two new species of the Torunotum Hosseini & Cassis, 2019—T. hirsutum sp. nov. and T. flavomaculatum sp. nov.—are diagnosed and described. Photographic images of habitus and male genital structures, as well as scanning electron micrographs of the selected structures of these species, are provided. Additionally, the paper also presents a new locality of Torunotum badius Hosseini & Cassis, 2019, along with photographs of the habitus and the male genitalia.

Preparation and Evaluation of Itraconazole Nanoparticle Lipid Carrier Gel for Dermatophytosis

Fungal infection is one of the common dermatological diseases. Drug delivery systems for topical use have shown significant advantages in targeting the drug to the action site in the body and also reduces the systemic side effects. Itraconazole was chosen as a model drug with low aqueous solubility. In the present study an attempt was made to prepare itraconazole loaded nanostructured lipid carrier (NLC). Different formulations were prepared by hot homogenization technique using solid lipid and liquid lipid (Compritol 888 & Caprol PGE 860) and surfactants (Poloxamer 188, tween 80). All the Formulations were characterized for drug content, entrapment efficiency, particle size, poly dispersity index, zeta potential &in vitro drug release and FTIR was done to study any interaction between excipients. The best formulation shows better drug release and entrapment efficiency 83.2%. the best formulation F3 showed better in-vitro drug release 55.46% at the end of 8th hour. The F3 was made into gel using Carbopol as a gelling agent. SEM study revealed that the NLC gel shows the particle size was found to be 500 nm in size smooth surfaces. NLC gel shows Drug release of NLC gel followed non- Fickian diffusion. NLC gel were stable at 40 ± 2ֹ°C and 75 ± 5% RH. Thus, the prepared NLC gel proved to be a potential candidate as a topical nanoparticulate sustained drug delivery system for itraconazole (BCS class II drug). keywords: Itraconazole, Nanoparticle Lipid Carrier, Lipids.

Late Holocene geochemical signature of inter reef mixed sediments on the northeastern Brazilian outer shelf

The northeastern outer shelf in Brazil is a complex ecotone that holds significant information on Holocene sedimentary processes and evolution. X-ray diffraction (XRD), X-ray fluorescence (XRF), and scanning electron microscopy/energy dispersive spectrometry (SEM/EDS) were employed to investigate bioclastic sedimentary facies and patches of relict siliciclastic sands. Radiocarbon dating (AMS) indicates that the carbonate sediments and corals formed in the past millennium. The sediment samples were divided into two groups using a multivariate analysis of XRD and XRF. The first group consists of siliciclastic materials, characterized by Si, Al, Fe, K, Zr, and Ti, and has low levels of carbonate and organic matter. The second, bioclastic and mixed facies, has a high carbonate content and exhibits elevated concentrations of Ca, Sr, and Mg, indicating authigenic processes. The EDS data revealed that the shells predominantly consisted of Cl, Cu, Al, Fe, and Ca. The terrigenous sites are detached from the coastal sources and are mainly located within the reef areas of the outer shelf. The erosion processes in these areas were inefficient to eliminate the siliciclastic sediments. This deposit trapped in inter reef sediments holds the key to understanding the timing and interactions between past coastal processes, shelf valley incision, and reef evolution during the Late Holocene transgression.

Shale anisotropic rock-physics model incorporating the effect of compaction and nonplate mixtures on clay preferred orientation

Compared with other sedimentary rocks, the strong elastic anisotropy of shale is extremely prominent, which is mainly caused by the preferred orientation and platy nature of its clay minerals. Especially in seismic reservoir characterization, a suitable and correct estimation of the shale elastic anisotropy can improve the accuracy of the shale seismic inversion and prediction. Due to the long-term compaction of shale and the rearrangement of minerals, its microstructure and macrostructure are more complex, resulting in obvious anisotropic characteristics of shale. Existing methods do not incorporate the impact of nonplate particles on clay platelets, or indirectly incorporate it through empirical formulas, resulting in poor applicability and errors in the rock-physics models. To reveal the main causes of the anisotropy of clay minerals, a theoretical model incorporating the effect of compaction and nonplate particles on the preferred orientation of clay platelets is developed using experimental data and electronic scanning results. Based on theoretical analysis, an orientation distribution function (ODF) based on the effect of compaction and nonplate particles is derived, which not only incorporates the influence of compaction but also further incorporates the effect of other nonplate particles, such as quartz, which makes the established shale anisotropic rock-physics model more reasonable and accurate. Then, an improved anisotropic shale rock-physics model is developed using the compaction and nonplate particles-based ODF. The prediction results indicate that the presence of nonplate particles has an inhibitory effect on the preferred orientation of clay platelets, which is verified by the measured experimental data and indicates that our method is reliable and effective.

FRACTURE MECHANISM ANALYSIS OF HIGH-DENSITY FIBREBOARD BASED ON DIGITAL IMAGE CORRELATION TECHNOLOGY

This paper analyses the scattering images of the bending deformation of high-density fibreboards based on the digital image correlation (DIC) technique, so as to study its mechanical deformation law. Three-point bending tests were carried out on fibreboards using a mechanical testing machine with a non-contact measuring system. The measured values of the displacements of the grid nodes in the region of interest (ROI) were combined with the Moving least squares (MLS) method to construct the strains of the high-density fibreboards at different loading forces, thus deriving the strain values of the fibreboards during the bending deformation process. To further analyze its force deformation mechanism, this paper used a portable electron microscope and scanning electron microscope to analyze the damage situation at the fracture damage, and at the same time, it verified that the constructed strain field model was accurate.

Systematic investigation of the influence of magnetic and non-magnetic ion substitutions in BiFeO3 under similar internal chemical pressure

Polycrystalline Bi1-xRxFeO3 (RHo and Y, x = 0.00, 0.05 and 0.10) compounds were prepared to perform a systematic investigation of the role of chemical nature and effect of internal chemical pressure on the structural, microstructural, magnetic, electric, ferroelectric and optical properties of the compounds. Structural analysis revealed that lattice distortions observed in Ho and Y-substituted compounds were not the same. The lattice parameters were larger in the case of the Y-substitution compared to the Ho-substituted counterpart. Scanning electron micrographs confirmed the formation of dense, well-connected grains exhibiting a reduction in size with increasing substitution. The magnetic properties of BiFeO3 were enhanced through the suppression of the spin structure with the substitution. The substitution of magnetic (Ho3+) ions led to an improvement in remanent magnetization and coercive field, whereas the substitution of non-magnetic (Y3+) ions resulted in enhanced maximum magnetization with negligible coercive field at room temperature. The ferroelectric measurements evidenced that both remanent polarization and coercive fields improved in substituted compounds, attributed to a decrease in charge carriers. Furthermore, the Y3+ ion substitution positively influenced ferroelectric properties by reducing leakage currents compared to the Ho3+ ion substitution. The optical absorption measurements indicated a decrease in the energy band gap of BiFeO3 with substitution, implying alterations in the material's optical characteristics. The ac conductivity studies demonstrated a discernible reduction in the conductivity of the substituted compounds. Specifically, Ho-substitution exhibited a more pronounced magnitude in the decline in conductivity relative to Y-substitution. This outcome signifies the potential efficacy of Ho-substitution in exerting control over the insulating characteristics of the compounds.

Safety research of textile materials with flame retardant properties

This article discusses the findings of a study that explored the use of new compositions containing tetraethoxysilane, sodium dihydrogen phosphate, and hexamethylenediamine to improve the flame retardancy of cellulose fiber materials. The impact of different components and temperatures on the fire-resistant properties of the fabric was examined. In an untreated sample measuring 17*22 cm, ignition occurred in 15 seconds and the fabric burned completely within 60 seconds, whereas a treated sample showed signs of retardation. Increasing the concentration of flame retardant impregnation at a temperature of 150 degrees had minimal effects on the material's strength, air permeability, and appearance. With the help of electron scanning device it was found that on the surface of the fibers of the treated sample morphological changes were observed in the form of film, which in turn contain particles of Si (25.48%), P (17.61%), Na (1.70%). The optimum conditions of fabric processing are determined, the influence of concentration of working solution, impregnation and thermofixation temperature on flame retardant properties of fabrics investigated, also processing can be carried out on standard equipment of finishing enterprises and laboratories. Cotton materials treated with a compound based on tetraethoxysilane, sodium dihydrophosphate and hexamethylenediamine provides adequate fire resistance.

Synthesis and release studies on amylose-based ester prodrugs of fenamic acid NSAIDs.

Aim: To achieve colon-targeted release of mefenamic acid from its ester-linked amylose prodrugs.Materials & methods: The prodrug was characterized by 1H NMR and IR spectroscopy. Drug activation and release profile was studied in enzyme enriched simulated physiological media via UV-vis spectroscopy and was validated with HPLC analysis. ELISA assay was employed for evaluating the % inhibition of COX-1 and COX-2 inhibition at different concentrations of the prodrug preincubated with ester and/ or amylose hydrolyzing enzymes. SEM studies further validated the performance of the prodrug under simulated physiological conditions.Results: Pancreatin was essential for the prodrug activation in SIM to make the ester bonds in prodrug vulnerable to hydrolysis by esterase. This evidence was confirmed by drug release studies, HPLC analysis, ELISA assay and SEM investigation where the ester conjugated prodrug showed marked stability in physiological media only to get activated in the presence of amylose degrading enzyme.Conclusion: Ester linked amylose-mefenamic acid conjugate showed both enzyme responsive activation and release in SIM.

Mechanistic role of vanadium microalloying in improving corrosion resistance of low carbon bainitic steel

We here investigated the effect of vanadium microalloying on the microstructure, mechanical properties, especially corrosion performances of low carbon bainitic steels. The corrosion behaviors of the steels with different vanadium contents in 3.5 wt% NaCl solution were evaluated by electrochemical tests (including polarization curves and electrochemical impedance spectroscopic measurements) and alternating immersion test (including weight loss and rust layer observation). Results show that the mechanical properties and corrosion resistance of low carbon bainitic steels can be synergistically improved with vanadium microalloying. With help of the electron backscatter diffraction characterization and scanning Kelvin probe force microscopy, we first discovered that although the number of micro-galvanic couples increases because of grain refinement, the Volta potential gradient between the matrix and grain boundaries are decreased with vanadium microalloying, which can promote the formation of compact protective rust layers and improve the corrosion resistance of vanadium micro-alloyed low carbon bainitic steels.

Microencapsulation by Complex Coacervation of Lavender Oil Obtained by Steam Distillation at Semi-Industrial Scale.

Lavender oil (LEO) is one of the most well-known essential oils worldwide which, besides its extensive application in aromatherapy, serves as raw material for various fields, including the food, cosmetic, and pharmaceutical industries. Accordingly, several global requirements were established to warrant its quality. Microencapsulation represents an emerging technology widely applied for the preservation of essential oils, simultaneously providing new ways of application. In the current study, lavender oil was obtained from the flowering tops of Lavandula angustifolia Mill. on a semi-industrial-scale steam distillation system. According to the GC-MS investigation, lavender oil obtained in the third year of cultivation met the European Pharmacopoeia standards for linalyl acetate and linalool contents ≈38% and ≈26%, respectively. Microcapsules (MCs) containing the so-obtained essential oil were successfully produced by complex coacervation technology between gum arabic (GA) and three different grades of type-A gelatin (GE). Optical microscopic investigations revealed a significant difference in particle size depending on the gelatin grade used. The variation observed for coacervates was well reflected on the scanning electron micrographs of the freeze-dried form. The highest encapsulation efficiency values were obtained by UV-VIS spectrophotometry for microcapsules produced using gelatin with the medium gel strength. FT-IR spectra confirmed the structural modifications attributed to microencapsulation. According to the GC-MS analysis of the freeze-dried form, the characteristic components of lavender oil were present in the composition of the encapsulated essential oil.

Biosynthesis and biological activities of magnesium hydroxide nanoparticles using Tinospora cordifolia leaf extract.

The synthesis of magnesium hydroxide nanoparticles (Mg(OH)2 NPs) using plant extracts are known to be a practical, economical, and an environmentally friendly approach. In this work, Mg(OH)2 NPs were synthesized using aqueous leaf extract of Tinospora cordifolia, a medicinal plant commonly found in India. The synthesized Mg(OH)2 NPs were characterized using various spectroscopic techniques. The ultraviolet-visible (UV-Vis) absorption peak of the Mg(OH)2 NPs was detected at 289nm, Fourier transform infrared (FTIR) analysis confirmed the presence of various functional groups, and X-ray diffraction (XRD) patterns revealed the well-crystallized structure of the Mg(OH)2 NPs. High-resolution transmission electron microscopy (HR-TEM) and scanning electron microscopy (SEM) analyses depicted spherical morphology and an average particle size (PS) of 27.71nm. The energy-dispersive X-ray (EDX) analysis confirmed the presence of C, O, and Mg elements, and the X-ray photoelectron spectroscopy (XPS) survey spectrum confirmed the elements for the Su 1s peak at 280.2eV. The dynamic light scattering (DLS) analysis displayed an average PS of 54.3nm, and the Zeta potential (ZP) was of 9.89mV. The fabricated Mg(OH)2 NPs displayed notable antibacterial activity against S. epidermidis, E. coli, and S. aureus. In addition, these NPs exhibited strong antioxidant properties (> 75%) based on DPPH, ABTS, and hydrogen peroxide (H2O2) assays. Further, the same NPs exerted a potent anti-inflammatory activity (> 65%) based on COX-1 and COX-2 evaluations. The anti-Alzheimer' disease (AD) potential of Mg(OH)2 NPs was assessed through effective inhibition (> 70%) of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities. Molecular docking (MD) studies confirmed that caryophyllene has higher binding affinity with AChE (-5.3kcal/mol) and BuChE (-6.4kcal/mol) enzymes. This study emphasizes the green synthesis of Mg(OH)2 NPs using T. cordifolia as a plant source and highlights their potential for biomedical applications.

Analysis of the Wear Parameters and Microstructure of High-Carbon Steel in Order to Identify Its Tribological Properties

Alloyed high-carbon steels are materials primarily intended for components operating under conditions of intense tribological wear. The carbides present in the microstructure of these materials significantly contribute to improving the wear resistance of such alloys. However, changes in the morphology of these precipitates can considerably alter the wear rate, leading to a deterioration in the properties of the materials. Therefore, this study aims to analyze the influence of several factors on the tribological wear of alloyed high-carbon steel. The research included friction tests under various load conditions and different sliding paths. Additionally, the samples were subjected to heat treatment to change the morphology of the observed precipitates. The tribological tests were conducted in a block-on-ring configuration under dry friction conditions. The tribological tests were analyzed statistically using analysis of variance (ANOVA). The results of the statistical analysis indicated that the primary factor influencing the observed differences between the samples was the heat treatment time of the material. Additionally, there were no significant statistical differences when pressure and friction path were varied. These findings, in conjunction with the SEM studies, allowed for the evaluation of the wear mechanism. The results demonstrated that, within the adopted tribological system, no alterations in the wear mechanism were observed with changes in test parameters. The observed differences in wear properties between the samples were found to be related to their heat treatment. The heat treatment resulted in alterations to the particle size distribution, with the annealing of the material at an elevated temperature leading to the dissolution of finer particles within the material. An increase in the average diameter of the carbide present in the material was observed to improve the wear resistance of the alloy tested.

Nitrogen and Oxygen Dual‐Doped Carbon as High‐Rate Long‐Cycle‐Life Anode Materials for Lithium‐Ion Batteries

Defect‐type carbon, doped with nitrogen and oxygen, is synthesized using the high‐temperature solid‐phase method. X‐ray photoelectron spectroscopy analysis reveals the presence of nitrogen, including pyridine nitrogen, pyrrole nitrogen, and graphitized nitrogen, incorporated into the carbon structure. Additionally, oxygen is introduced into carbon, with both CO and CO functionalities are observed. Transmission electron microscopy and scanning electron microscopy indicate that all samples exhibit a morphology of carbon microblocks with localized turbocharged lattice regions. Electrochemical tests demonstrate that the nitrogen‐ and oxygen‐doped carbon microblocks exhibit excellent cycling performance and high rate capacity. Specifically, at current densities of 1 and 2 A g−1, the rate capacity remains at 385.6 and 214.4 mA h g−1, respectively. Furthermore, the discharge capacity at 5 A g−1 remains at 58.3 mA h g−1 on the 3500th cycle. The defects introduced by nitrogen and oxygen doping not only enhance reactivity and electronic conductivity but also improve lithium‐ion diffusion dynamics.

Sphere-like Nb2O5 nanoparticles by waste Brassica oleracea leaf extract for lead removal and photocatalytic degradation of methylene blue dye

Currently, water-soluble pollutants such as hazardous chemicals and pigments create severe environmental hazards. Heavy metals such as lead, chromium, mercury, and arsenic were dangerous to living beings even at very low levels. To overcome this limitation, Nb2O5 nanoparticles were created utilizing a novel green approach. Based on plant components, green technique is a low-cost, safe, and environmentally good solution. In the present inquiry, we employ phytonutrients from waste Brassica oleracea leaf juice as a capping and reducing component. The product was evaluated using XRD, FT-IR, UV, SEM, and TEM techniques. The findings showed that the produced Nb2O5 NPs had a sphere-like geometry having a median particle dimension of 9 nm confirmed by XRD analysis. SEM study reveals ultrafine, homogeneous morphological agglomerations and uniform granules in TEM analysis, 10–15 nm particles predicted by crystallography, orthorhombic Nb2O5 (001) planes matching 0.39 nm lattice edge measurement error, and a clearly defined SAED diffract signal implying polycrystalline calcined powder. Excitation absorbance bands at 350 nm may be caused by charged balancing in the Nb–O–Nb architecture increasing oxygen concentration confirmed by UV–Vis analysis. The Nb2O5 nanosphere has a surface area of 120 m2/g, 0.592 cm2/g of pores, and a mean pore dimension of 15.2 nm, determined using Barrett-Joyner-Halenda (BJH). A sequential Adsorption capacities assay shown that it is an effective absorber used to eliminate Pb (II) ions from aqueous solutions. Adsorbents was able to be readily removed from the resultant fluid and recycled repeatedly. The produced Nb2O5 Nanoparticles are capable of removing toxic heavy metals and synthetic colors from polluted waterways.