Scanning Electron Microscopy-energy Dispersive X-ray Research Articles

The Complex of Cr(III) with Ligand of 2,6-Bis(pyrazol-3-yl)pyridine and Anionic Trifluoromethanesulfonate: Synthesis, Characterization and Antibacterial Activity

The complex containing chromium(III), 2,6-bis(pyrazol-3-yl)pyridine (3-bpp), and CF3SO3– (trifluoromethanesulfonate (triflate)) has been prepared and characterized. The conductance, metal content, and thermogravimetric and differential thermal analysis (TGA-DTA) analysis suggest the complex to be [Cr(3-bpp)2](CF3SO3)3.2H2O. The paramagnetic moment corresponds to the three unpaired electrons being consistent with the electronic configuration of chromium(III). The electronic spectral bands are not well resolved attributed to the spin-allowed transitions of quartet ground state to quartet excited states. The IR spectral data signify the mode of vibrations typical for 3-bpp as well as the triflate. While the images of scanning electron microscope-energy dispersive X-ray (SEM) photographs confirm the crystalline particle size and the energy dispersive X-ray (EDX) signifies the existence of all elemental content. The analysis of powder-X-ray diffraction (powder-XRD) following the Rietica program of Le Bail suggests being a structurally orthorhombic crystal system, and Pbca space group, with Z = 16, Rp = 4.30, Rwp = 5.14, Rexp = 12.17, R-FBragg = 0.04, and goodness of fitting (GOF) = 0.1783. The complex shows a weak inhibition of bacterial activity against S. aureus and E. coli.

Comparison of remineralization ability of tricalcium silicate and of glass ionomer cement on residual dentin: an in vitro study

ObjectiveThis study aimed to compare the remineralization effects of a calcium silicate-based cement (Biodentine) and of a glass ionomer cement (GIC: Fuji IX) on artificially demineralized dentin.MethodsFour standard cavities were prepared in dentin discs prepared from 34 extracted sound human third molars. In each disc, one cavity was covered with an acid-resistant varnish before demineralization (Group 1). The specimens were soaked in a chemical demineralization solution for 96 h to induce artificial carious lesions. Thereafter, one cavity each was filled with Biodentine (Group 2) and GIC (Group 3), respectively, and one carious lesion was left unrestored as a negative control (Group 4). Next, specimens were immersed in simulated body fluid (SBF) for 21 days. After cross-sectioning the specimens, the Ca/P ratio was calculated in each specimen by using scanning electron microscopy–energy-dispersive X-ray spectroscopy (SEM-EDX). Finally, data were analyzed using repeated-measures ANOVA with post-hoc Bonferroni correction.ResultsBoth cement types induced dentin remineralization as compared to Group 4. The Ca/P ratio was significantly higher in Group 2 than in Group 3 (p < 0.05).ConclusionThe dentin lesion remineralization capability of Biodentine is higher than that of GIC, suggesting the usefulness of the former as a bioactive dentin replacement material.Clinical relevanceBiodentine has a higher remineralization ability than that of GIC for carious dentin, and its interfacial properties make it a promising bioactive dentin restorative material.

Synthesis of Hydroxyapatite from Precipitated Calcium Carbonate of Thorny Shells (Murex trapa) with Variable Ca/P Mole Ratio and pH

Hydroxyapatite, with the chemical formula Ca10(PO4)6(OH)2, is a mineral found in human bones and teeth, providing density and strength to bones as it is a major component of the bone matrix. It is widely used in biomedicine for bone implants, dental fillings, and hard tissue replacement. Hydroxyapatite can be produced from materials high in CaCO3, such as cattle bones, seashells, and fish bones. In this research, thorny clam shells (Murex trapa), with a CaCO3 content of 91.08%, were used. Precipitated Calcium Carbonate (PCC) was formed using the carbonation method, while hydroxyapatite synthesis was performed using the precipitation method. Variables during synthesis included Ca/P molar ratios of 1.47, 1.67, and 1.87, and pH levels of 7, 9, and 11. The best result was achieved at a Ca/P molar ratio of 1.67 and pH 9, with a yield of 96%. The hydroxyapatite was analyzed using Fourier Transform Infra-Red, revealing the core groups PO43-, CO32-, and OH-.Scanning Electron Microscopy-Energy Dispersive X-Ray analysis showed the hydroxyapatite had a crystalline structure, tending to be spherical and agglomerated.

Efficient photocatalytic activity and selective adsorption of UiO-67 (Zr)/g-C3N4 composite toward a mixture of parabens

In this study, UiO-67 (Zr)/g-C3N4 composites (U67N) were synthesized at wt.% ratios of 05:95, 15:85, and 30:70 using the solvothermal method at 80 °C for 24 h followed by calcination at 350 °C. The composites were characterized using UV–Vis diffuse reflectance spectroscopy, Fourier-transform infrared spectroscopy, photoluminescence spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, scanning electron microscopy–energy-dispersive X-ray spectroscopy, transmission electron microscopy, and nitrogen physisorption analysis. In addition, thermal stability analysis of UiO-67 was conducted using thermogravimetric analysis.The photocatalytic performance of the composites was assessed during the degradation and mineralization of a mixture of methylparaben (MeP) and propylparaben (PrP) under simulated sunlight. The adsorption process of U67N 15:85 was characterized through kinetic studies and adsorption capacity experiments, which were modeled using pseudo-first-order and pseudo-second-order kinetics and Langmuir and Freundlich isotherms, respectively.The influence of pH levels 3, 5, and 7 on the photocatalytic degradation of the mixture was investigated, revealing enhanced degradation and mineralization at pH 3. The U67N composite exhibited dual capability in removing contaminants through adsorption and photocatalytic processes. Among the prepared composites, U67N 15:85 demonstrated the highest photocatalytic activity, achieving removal efficiencies of 96.8% for MeP, 92.5% for PrP, and 45.7% for total organic carbon in 300 kJ/m2 accumulated energy (3 h of reaction time). The detoxification of the effluent was confirmed through acute toxicity evaluation using the Vibrio fischeri method.The oxidation mechanism of the heterojunction formed between UiO-67 (Zr) and g-C3N4 was proposed based on PL analysis, photoelectrochemistry studies (including photocurrent response, Nyquist, and Mott–Schottky analyses), and scavenger assays.

Iron deposition in gastric black spots: Clinicopathological insights and NanoSuit-correlative light and electron microscopy analysis.

Black spots (BSs) are lentiginous findings observed in the gastric body and fundus during upper gastrointestinal endoscopy and are predominantly seen in patients undergoing Helicobacter pylori eradication treatment. However, the detailed patient background and exact composition are poorly understood. This study aims to clarify the clinicopathological features of BSs, examine patient demographics, and use the NanoSuit-correlative light and electron microscopy (CLEM) method combined with scanning electron microscopy-energy dispersive X-ray spectroscopy for elemental analysis. Patients who underwent upper gastrointestinal endoscopy between 2017 and 2022 were included. Data on age, medications, blood tests, and H. pylori infection status were retrospectively gathered from medical records. Univariate analysis was conducted to examine BS presence, with results then used in a multivariate model to identify associated risk factors. Additionally, pathological specimens from patients with BSs were analyzed for elemental composition using the NanoSuit-CLEM method combined with scanning electronmicroscopy-energy dispersive X-ray spectroscopy. An analysis of 6778 cases identified risk factors for BSs, including older age and using proton pump inhibitors, statins, corticosteroids, and antithrombotic drugs. Endoscopically, BSs correlated with higher gastric atrophy and lower active H. pylori infection. Iron deposition at BS sites was specifically identified using NanoSuit-CLEM. BSs on gastrointestinal endoscopy may indicate an absence of active H. pylori inflammation. The discovery of iron deposition within BSs using the NanoSuit-CLEM method has offered new insights into the possible causative factors and advances our understanding of the etiology of BSs, bringing us closer to unraveling the underlying mechanisms of their formation.

Synergistic Effect of 3D/2D Vanadium Diselenide/Tungsten Diselenide Hybrid Materials: Electrochemical Detection of 5-Nitroquinoline a Hazard to the Aquatic Environment.

The development of multidimensional structured electrode materials with simple synthetic methods and their electrochemical sensing ability against environmental pollution is still a challenge. In this article, we propose a hybrid formed using multidimensional (3D/2D) vanadium diselenide microspheres and tungsten diselenide nanosheets (VSe2/WSe2) for the electrochemical detection of 5-nitroquinoline (5-NQ), a highly toxic and hazardous substance that is polluting aquatic life due to increasing industrial activities. The 3D/2D VSe2/WSe2 hybrids were prepared by a simple solvothermal method and their morphological and structural analysis was confirmed by various spectroscopy and analytical techniques such as powder X-ray diffraction, X-ray photoelectron spectroscopy, field emission scanning electron microscopy-energy dispersive X-ray spectroscopy, transmission electron microscopy, cyclic voltammetry, and differential pulse voltammetry. The proposed 3D/2D architecture showed a strong synergistic effect between the two components as well as high electrical conductivity. As a result, an increased peak current for the reduction and detection of 5-NQ was achieved compared to other modified and unmodified disposable screen-printed electrodes (SPE), such as bare SPE, VSe2/SPE, and WSe2/SPE. Under the optimized electrochemical conditions, VSe2/WSe2/SPE showed large linear response ranges (0.012-1053, 1183-3474 μM), a low detection limit (0.002 μM), good sensitivity along with good selectivity, and repeatability for the detection of 5-NQ. With this prominent electrochemical behavior, the VSe2/WSe2 electrode has clear potential to produce high-performance sensor devices.

Corrosion inhibitive performance of Kopsia teoi extracts towards mild steel in 0.5 M HCl solution

This study investigates the capacity of Kopsia teoi (K. teoi) to inhibit corrosion, employing its stem extracts to prevent mild steel (MS) corrosion in 0.5 M HCl. In this study, three distinct extracts: dichloromethane alkaloid (KTDAE), dichloromethane non-alkaloid (KTDNAE), and methanol (KTME) were employed to investigate their corrosion mitigation performance, involving electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PD) techniques. EIS results demonstrated a significant increase in inhibition efficiency with concentration for each extract, reaching 87.04, 90.62, and 93.51 % for KTDAE, KTDNAE, and KTME, respectively. According to PD analysis, Kopsia teoi extracts (KTEs) functioned as mixed-type inhibitors. Surface analysis through scanning electron microscopy-energy dispersive X-ray spectroscopy exhibited notable improvements in the morphology of treated MS plates, revealing the establishment of a protective surface film. Langmuir isotherm confirmed that KTEs formed a monolayer on MS surface, and the calculated free energies of adsorption were −25.924, −26.809, and −27.687 kJ mol−1 for KTDAE, KTDNAE, and KTME, respectively. This suggests effective adsorption through both physisorption and chemisorption mechanisms. Consequently, the results of this study highlight the encouraging effectiveness of KTEs as corrosion inhibitors for MS in acidic environments.

The development of titanium dioxide nanotube-supported CdTe catalysts for photocatalytic enzymatic glucose fuel cell and response surface methodology optimization

Energy is one of the critical needs for human life and well-being. Alternative energy sources are essential due to the increase in energy demand with the rise in population the development of industrialization, and the damage caused by fossil fuels to the environment. Fuel cells, an alternative energy source, are a clean and environmentally friendly technology that converts chemical energy into electrical energy. In this study, titanium dioxide (TiO2) nanotube (TNT)-support CdTe catalysts were synthesized by the wet impregnation (WI) method. Glucose oxidase (GOD) and laccase (LAC) enzymes were modified by incubation on CdTe/TNT catalysts. These enzymatic and non-enzymatic catalysts were characterized by scanning electron microscope-energy dispersive X-ray (SEM-EDX) and mapping, X-ray diffraction (XRD), Raman spectroscopy, and transmission electron microscope (TEM) analyses. Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and chronoamperometry (CA) analyses were used to examine the activity, resistance, and stability of catalysts for enzymatic photocatalytic glucose electrooxidation. The 3 % CdTe(50-50)-TNT-GOD/GCE electrode exhibited the highest activity, resistance, and stability under UV illumination compared to other electrodes. The modification parameters of the electrodes, incubation time, amount of catalyst ink, and drying time were found to be 136.96 min, 8.94 µL, and 21.30 min with response surface method (RSM) analysis, respectively. The estimated specific activity value was obtained as 0.754 mA/cm2 under optimized conditions.

“Hearts of gold” (Cuori d'oro): The case study of the leather corami of Palazzo Chigi in Ariccia

In this work we present the results obtained by different technical analysis in order to perform the characterization of the chromatic richness, the employed materials and the iconographic elements of different fragments of decorated and gilded leather corami coming from the archive of Palazzo Chigi of Ariccia (Rome) and employed, during the 17th century, as wallcoverings. Different microscopic and spectroscopic analyses have been performed by means of Ion Beam Analysis (IBA) and Macro Area X-Ray Fluorescence (MA-XRF) techniques available at the INFN LABEC ion beam laboratory in Florence and the Scanning Electron Microscopy-Energy Dispersive X-ray Analysis (SEM-EDX) of the Superconductivity Laboratory of the ENEA Frascati Research Center. The results aim to provide the scholar information about the manufacturing process and the materials employed for the production of these peculiar artefacts, also in order to plan the best and most appropriate conservation protocol. In particular, thanks to the SEM-EDX analysis it has been possible to characterize the layered structure of the samples and, specifically, the interface between the leather of the substrate, the metal foil of the so called meccatura and between these and the overlying pictorial layer. The IBA and MA-XRF techniques has helped in characterizing the painting palette employed while IBA has allowed to determine the conservation condition of the silver layer with the hypothesis of the incorporation of the silver leaf into the organic compound of the mecca as its main deterioration phenomena. These complementary techniques provide, therefore, a comprehensive understanding of the materials and iconographic elements of these leather-based artefacts, which is essential for their preservation and restoration as well as they contribute to a better understanding of the deterioration processes they incur.

The utilization of ionic liquids as sustainable and eco-friendly inhibitors for corrosion protection of carbon steel in petroleum fields

Various ionic liquid compounds are synthesized from the combination of iminodiethanol and fatty acid of butyric (IL-4) caprylic (IL-8) and capric (IL-10). The composition of such compounds was confirmed by various spectroscopic techniques and was tested as mitigators for the destruction of carbon steel in 10 % diluted oil field-produced water. The measurements of electrochemical potentiodynamic polarization, impedance spectroscopy, and gravimetry were complemented by surface investigation of some corroded carbon steel samples utilizing scanning electron microscopy-energy dispersive X-ray analysis (SEM-EDX). The data indicated that the addition of IL-4, IL-8, and IL-10 inhibits the destruction of carbon steel in the 10 % diluted oil field-produced water by lowering the corrosion current density (Iorr) and the double-layer capacitance (Cdl). Tafel polarization data confirmed that the studied compounds acted as mixed inhibitors. The values of the cathodic Tafel slope, bc, are found to be close to each other confirming that the adsorbed compounds did not alter the mechanism of hydrogen evolution. The charge transfer resistance, Rct, for the blank solution is 1501 and increased with the addition of such compounds to reach 5332 at a concentration of 500 mg/l of IL-10 with a protection efficiency of 85.83 %, at 25 ◦C. The computed -ΔG°ads values varied between −18.11 and –23.98kJ mol/1 depending on the type of inhibitor and the temperature, which confirms the suggestion of the physisorption mechanism. The negative values of ΔG°ads explain the spontaneity of the adsorption process. The lowering in Kads values with T is attributed to the escaping of some of the adsorbed inhibitor molecules leaving the carbon steel surface. Theoretical quantum computation was used to confirm the adsorption ability of various ionic liquids on the examined metal.

Investigation of the Adsorption Characteristics of &lt;i&gt;Theobroma cacao&lt;/i&gt; Peels Biomass Inhibitors on Mild Steel Surfaces by EIS, SEM-EDX, XPS, and Chemical Studies in Acidic Media

Investigators used Potentiodynamic Polarization, Spectroscopy of Electrochemical Impedance (EIS), Scanning Electron Microscope-Energy Dispersive X-Ray (SEM-EDX), Spectroscopy of X-Ray Photoelectron (XPS), and chemical studies to examine the inhibitory effect of Theobroma cacao peel extract (TCPE) on mild steel (MS) corrosion in 1.5M HCl. Studies of electrochemical data indicate that, TCPE reduces MS corrosion through adsorption using a mixed inhibition mechanism. As the inhibitor concentration grows and temperatures lowers, TCPE becomes more protective. The adsorption of TCPE molecules on the MS surface is controlled by the Langmuir adsorption isotherm. To determine the correlation between the hampers effect and the structure of TCPE molecular, a number of chemical characteristics were computed.

Surface Modification of Graphene Oxide for Fast Removal of Per- and Polyfluoroalkyl Substances (PFAS) Mixtures from River Water.

Per- and polyfluoroalkyl substances (PFAS) make up a diverse group of industrially derived organic chemicals that are of significant concern due to their detrimental effects on human health and ecosystems. Although other technologies are available for removing PFAS, adsorption remains a viable and effective method. Accordingly, the current study reported a novel type of graphene oxide (GO)-based adsorbent and tested their removal performance toward removing PFAS from water. Among the eight adsorbents tested, GO modified by a cationic surfactant, cetyltrimethylammonium chloride (CTAC), GO-CTAC was found to be the best, showing an almost 100% removal for all 11 PFAS tested. The adsorption kinetics were best described by the pseudo-second-order model, indicating rapid adsorption. The isotherm data were well supported by the Toth model, suggesting that PFAS adsorption onto GO-CTAC involved complex interactions. Detailed characterization using scanning electron microscopy-energy dispersive X-ray spectroscopy, Fourier transform infrared, thermogravimetric analysis, X-ray diffraction, and X-ray photoelectron spectroscopy confirmed the proposed adsorption mechanisms, including electrostatic and hydrophobic interactions. Interestingly, the performance of GO-CTAC was not influenced by the solution pH, ionic strength, or natural organic matter. Furthermore, the removal efficiency of PFAS at almost 100% in river water demonstrated that GO-CTAC could be a suitable adsorbent for capturing PFAS in real surface water.

Immobilization of HRP enzyme on polymeric microspheres and its use in decolourisation of organic dyes

In this study, horseradish peroxidase (HRP) enzyme was immobilized on Pd(II) containing polymeric microspheres by adsorption method and used for the decolourisation of Methyl Orange (MO) and Rhodamine B (RB) dyes. The synthesized microspheres were characterized by Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy-Energy Dispersive X-ray (SEM/EDX), Thermal Gravimetric Analysis (TGA). The effects of pH, dye concentration, temperature, and H2O2 concentration on the decolourisation of MO and RB were determined. According to the results of various parameters studied, when 2-AEPS-napht-HRP support was used, MO and RB were biodegraded to 69.72% and 80.65%, respectively, within 60 min. When 2-AEPS-napht-Pd-HRP support was used, MO and RB were biodegraded to 58.35% and 90.81%, respectively, under optimum conditions. When the reproducibility results of the immobilized supports were examined, it was observed that they remained efficient during the first five reusability cycles and even reached 65% decolourisation efficiency after the 9th reuse. The immobilized enzyme (2AEPS-npht-HRP and 2AEPS-npht-Pd-HRP) showed remarkable resistance to higher temperatures compared to the free enzyme.

Sustainable and Novel Development of Metal Matrix Composite Using Scrap Aluminium Alloy Reinforced with Scrap Borosilicate Glass Particles by Stir Casting Technique

This study aims to achieve a sustainable and environmentally friendly approach to the development of metal matrix composites (MMCs) by utilizing locally available Scrap Aluminium Engine Heads (SAEH) as the matrix material and powdered Scrap Borosilicate Glassware (SBG) as reinforcement. The stir casting technique was employed for composite fabrication, combining the benefits of cost-effectiveness and ease of processing. The research evaluates the mechanical properties of the developed MMC, including tensile strength, compressive strength, hardness, and impact resistance. Physical properties such as density and porosity were also investigated, alongside microstructural analysis using optical microscopy, scanning electron microscopy (SEM), SEM energy-dispersive X-ray analysis (EDAX), and X-ray diffraction (XRD). The results demonstrate a significant improvement in the mechanical properties of the composite compared to the as-cast SAEH material. The ultimate tensile strength increased from 70.3 MPa for as-cast SAEH to 117.3 MPa for SAEH reinforced with SBG. Similarly, ultimate compressive strength improved from 513.7 MPa to 700.67 MPa, and hardness increased from 32.56 HRB to 43.33 HRB. Furthermore, the impact strength showed a notable enhancement, increasing from 1.4 Joules to 1.8 Joules. Importantly, the porosity percentage decreased from 14.28% in as-cast SAEH to 9.97% in SAEH+BS composites, indicating improved material density. This research contributes to the development of sustainable MMCs using recycled materials, offering enhanced mechanical properties and reduced environmental impact, making it valuable for various engineering applications. By aligning with Sustainable Development Goals (SDGs), this study addresses key sustainability targets and underscores the importance of environmentally responsible materials development in advancing global sustainability efforts.

A Study of Protective Coatings for Archaeological Silver

ABSTRACT This study investigates the sustainability and efficacy of coatings for archaeological silver. Building on a survey of current practices in silver conservation and a literature review, a group of Chimú (Peruvian north coast, 1100–1400 CE) silver alloy items in the National Museum of the American Indian collection serves as a case study. Assessing treatment options for 80 Chimú items led to the investigation into the implications of introducing a new coating campaign. Experimentation was carried out with coupons approximating the composition and manufacture of Chimú silver. Four conservation grade materials, Agateen® 27, Acrysol® WS24, Paraloid® B-72, and Regalrez® 1126, were tested for protection efficacy in a humid, sulfur-containing environment. Analysis with X-ray fluorescence spectroscopy (XRF), scanning electron microscopy energy-dispersive X-ray spectroscopy (SEM-EDX), and imaging at several phases throughout the experiment provided data on the interaction of the metal and the coating and the effects of coating and re-coating. Oddy testing and Fourier transform infrared spectroscopy (FTIR) conducted on these prepared coatings helped determine their suitability for long-term use. Results indicate that not coating is more appropriate for preservation than coating with any of the four materials tested.

Synthesis, crystal structure of Ca6Sb2O11 from experiments and DFT-electron structure calculation

This article reports a new perovskite compound Ca6Sb2O11. The X-ray powder diffraction technique was used to analyze its crystal structure. The results show that Ca6Sb2O11 has a tetragonal structure with the I4/m space group, and the lattice parameters are a = b = 5.658 (1) Å, c = 7.984 (1) Å, α = β = γ = 90°. It exhibits a typical A4B'2B″2X12-x anoxic multi-perovskite structure with rock-salt ordering of the B-site cations. The compound's chemical composition and valence states were characterized through scanning electron microscopy-energy dispersion spectrum (SEM-EDS) and X-ray photoelectron spectroscopy (XPS). The presence of oxygen vacancies was confirmed by electron paramagnetic resonance (EPR) spectroscopy. A chemical and structure transition temperature and the full melting temperature of Ca6Sb2O11 were measured, with values of 1515 ± 3 K and 1720 ± 3 K, respectively. The density functional theory (DFT)-electron structure calculation results show that Ca6Sb2O11 is an indirect wide-band gap (∼4.47 eV) semiconductor material, which agrees well with the experimental value (∼4.38 eV) obtained through diffuse reflection spectroscopy (DRS). Moreover, the top of the valence band and bottom of the conduction band are mainly contributed to by O-2p and Ca-3d states, respectively.

A New Electrochemical Sensor for the Detection of Azithromycin using Screen‐Printed Carbon Electrode Modified with Boron‐Doped Diamond Nanoparticles and Reduced‐Graphene Oxide

AbstractExcessive use of azithromycin (AZM) is associated with resistance and negative impacts on the environment. Therefore, this study aimed to develop an electrochemical sensor for AZM. The screen‐printed carbon electrode (SPCE) modified with boron‐doped diamond nanoparticle (BDDNP) and reduced‐graphene oxide (rGO) was successfully applied to measure the AZM concentration. The morphology of the modified electrode was characterized by scanning electron microscopy‐energy dispersive X‐ray (SEM‐EDX). Furthermore, the effect of electrochemical parameters, such as signal per background, scan rate, and selectivity was determined. The results showed that under optimum conditions, the plot of AZM demonstrated linearity in the range of 30–100 μM with a limit of detection (LOD) at 1.6 μM. The repeatability and recovery were also investigated, and the sensor was applied to real samples obtained from hospital wastewater. A remarkable 93.27 % recovery rate and excellent precision were recorded with an %RSD of 2.41 %. This study underscores the potential of SPCE modified with rGO/BDDNP for accurate and reliable measurement of AZM levels, showcasing great applicability in addressing the challenges associated with monitoring AZM in various environmental settings.

Advancement in embedding Pb quantum dots into a Porous-Si matrix for superior X-ray radiation detection: An extended gate approach

This study reports on the synthesis of porous silicon (PS) and porous silicon doped with lead (PS–Pb) using an electrochemical method with a primary focus on optimizing key synthesis parameters to enhance material properties. During the synthesis, hydrofluoric acid (HF) and ethanol ratios were maintained at 4:1, which was crucial in achieving the desired structural properties. A structural analysis of the synthesized nanocomposites was conducted using Field Emission Scanning Electron Microscopy-Energy Dispersive X-ray Spectroscopy (FESEM-EDX). This structural analysis validated the successful incorporation of lead (Pb) into the samples. Among the key aspects of this study were the evaluation of the I–V characteristics of the PS-Pb nanocomposites. Based on the findings of I–V measurements, an increase in the bias voltage was observed, which was directly correlated with an increase in measured current, indicating significant changes in electrical properties as a result of Pb doping. Furthermore, the responses of these materials to X-ray pulse irradiation under various conditions were successfully measured and compared, enhancing the understanding of their potential as radiation detectors. The optimal electrochemical conditions for synthesizing PS and Pd-PS were identified as 90 V, 100 mA, 1 s, and 100 V, 100 mA, 0.5 s, respectively. As a result of optimizing electrochemical synthesis parameters, lead-doped porous silicon (Pb-PS) exhibited a marked reduction in pore size, decreasing from an average of 420.88 nm in undoped PS to 244.54 nm in Pb-PS. This structural refinement correlated with improved electrical properties; I–V measurements demonstrated that the current response at a bias voltage of 0.3 V improved from 1.6×10−5 A to 6.23×10−4 An under identical conditions. Furthermore, these materials responded to X-ray radiation and showed enhanced sensitivity, with Pb-PS detectors achieving a lower response time and higher current under X-ray exposure compared to undoped PS. These findings open up new avenues for employing these nanocomposites in advanced applications, particularly in fields that require precise and efficient radiation detection, such as medical imaging and environmental monitoring. This work represents a significant contribution to the field, illustrating the potential of these custom-engineered materials for the advancement of modern healthcare and detection technologies.

Palm Oil Mill Effluent Biochar as An Alternative Potassium Source: Effect of Pyrolysis Time and Its Kinetic Release

Palm Oil Mill Effluent (POME) is one of the waste products of palm oil processing that can be processed into a biochar. POME biochar contains high levels of nutrient, such as NPK which can be used an alternative potassium source material. This study aims to produced biochar from POME and the influence of pyrolysis time on the characteristics and its kinetic release. Biochar production from POME was conducted at 300oC with pyrolysis time variation of 1 hour, 3 hours and 5 hours. Biochar characterization was conducted using Fourier Transform Infrared (FTIR) Spectroscopy, Scanning Electron Microscope-Energy Dispersive X-ray (SEM-EDX), Surface Area Analysis (SAA). Study of potassium release was conducted by mixing one gram amount of biochar with 0.01 M CaCl2 as a function of time. The used kinetics modelling in this study are first-order, second-order, pseudo-first order, pseudo-second orde. The results showed that the biochar yield decreased, while the biochar pH value, exchangeable potassium, non-exchangeable potassium and surface area increased with the increasing of pyrolysis time. The pseudo- second order model is the most fitted model to describe the potassium release. The pseudo-second order kinetics model gave K release rates of 0.018; 0.024; 0.020; 0.014 (mg g-1min-1), the qe values are 0.814; 0.839; 0.927; 1.111 (mg g-1), respectively.

INFLUENCE OF PRECURSOR MOLARITY AND LEAF EXTRACT CONCENTRATION ON PHYSICAL PROPERTIES OF ZINC OXIDE (ZnO) NANOPARTICLES SYNTHESIZED USING MORINGA OLEIFERA LEAF EXTRACT

Zinc oxide nanoparticles (ZnONPs) exhibit optical, electrical, and magnetic properties depending on their size and morphology. These properties are essential for using ZnONPs in various fields such as cosmetics, electronics and medicine. The properties and applications of ZnONPs depend on how they are synthesized, whether physical, chemical, or biological. This study aimed to produce ZnONPs by utilizing the leaf extract of Moringa oleifera and to study the effect of precursor molarity and leaf extract concentration on physical properties. The precipitated compound was characterized using X-ray diffraction (XRD), ultraviolet-visible spectroscopy (UV-Vis), and Scanning Electron Microscopy-Energy Dispersive X-ray spectroscopy (SEM-EDAX). Here, we prepared ZnONPs under four different molarity (0.2[Formula: see text]M, 0.3[Formula: see text]M 0.4[Formula: see text]M, and 0.5[Formula: see text]M) and two different leaf extract concentrations (10[Formula: see text]ml, 15[Formula: see text]ml). We analyzed the difference obtained in the average particle size in each case. From the XRD the major diffraction peaks are observed at 36.3, 47.53, 36.33, and 36 for 0.2[Formula: see text]M, 0.3[Formula: see text]M, 0.4[Formula: see text]M, and 0.5[Formula: see text]M, respectively. The average particle size was found to be in the range of 12–30[Formula: see text]nm. UV study was used to inspect the optical nature of the prepared ZnONPs and SEM confirmed the sample’s morphology. Investigations on the role of precursor molarity and leaf extract concentration in synthesizing ZnONPs indicated that average particle size increases with increasing precursor molarity and leaf extract concentration. The study also suggested that synthesizing metal oxide nanoparticles using botanical extract is an eco-friendly alternative to physical and chemical methods.