Elemental Composition Research Articles

In Ukrainian

The CMs were obtained in argon in three stages: 1) heating (4 grad/min) to the specified temperature t in the range of 350–825 °С; 2) isothermal exposure 1 h; 3) cooling, washing from alkali and drying. Samples are denoted as CM(t). The CM yield (Y, %) and CMs elemental composition are determined. Based on low-temperature (77 K) nitrogen adsorption-desorption isotherms, integral and differential dependences of the specific surface area SDFT (m2/g) and pore volume V (cm3/g) on the average pore diameter (D, nm) were calculated by 2D-NLDFT-НS method (SAIEUS program). They were used to define volumes of ultramicropores (Vumi), supermicropores (Vsmi) and micropores (Vmi). The total pore volume V was calculated from the nitrogen amount adsorbed at a relative pressure p/p0 ~ 1.0. The S values of ultramicropores (Sumi), supermicropores (Ssmi) and micropores (Smi) were similarly determined. The CM yield was established to decrease linearly (R2 = 0.979) from 70.2 to 45.3 % with an increase in temperature from 350 to 825 °С. The carbon content decreases to a minimum value at 500 °С (72.6 %), and then increases to a maximum value (87.5 %) at 825 °С; the oxygen content changes antibatically. Two temperature regions were identified: region I (≤ 500 °С) of increasing the oxygen content due to reactions in which KOH acts as a donor of O atoms; region II (≥ 500 °C) of dominating the thermal destruction of functional groups (carboxyl, lactone, ester) with the release of CO and CO2, and condensation increasing the size of polyarenes of the CM secondary framework and formsng single Сar-Саr bonds between them. The CM(350) sample was found to contain only mesopores (D ≥ 10 nm) and macropores. An activation temperature increase to 400 °C initiates the additional formation of small-diameter micropores and mesopores. In samples CM(400) - CM(825), the main portion of newly formed pores falls on pores with D ≤ 5 nm. With increasing temperature, the micropores volume increases almost linearly (R2 = 0.992). The Vumi and Vsmi volumes increase up to 600 °C. At higher temperatures the ultramicropores volume decreases due to transforming ultramicropores (D ≤ 0.7 nm) into supermicropores (D = 0.7–2.0 nm). Portion of the ultramicropores volume changes with a maximum (23.9 %) in the CM(600) sample. The SBET specific surface area linearly (R2 = 0.992) increases with temperature up to 1729 m2/g. The SDFT values are close to SBET, but noticeably lower (1514–1530 m2/g) for CM(785)-CM(825). The micropores specific surface area increases to 1415 m2/g, and ultramicropore surface Sumi changes extremely with a maximum (526 m2/g) for the CM(600) sample, which should be expected based on the temperature dependence of the Vumi parameter. The decrease in Sumi values after the maximum is compensated by an increase in the supermicropore surface. Such an effect - the redistribution of pores by size in the microporous range (D ≤ 2 nm) with an increase in the alkaline activation temperature is not described in the literature. The portion of the micropores surface is dominant (92.6–97.0 %) in samples prepared at t ≥ 450 °C. The portion of the ultramicropore surface is maximum (56.3 %) in CM(500). Pores are revealed that do not form at all at 450–750 °C. These are supermicropores (D = 0.96–2.00 nm) and mesopores of small diameters (D = 2.0–2.82 nm). This effect was assumed to be due to the properties of the CM supramolecular framework, which is formed from polyarene fragments of the initial and activated coals having polyarenes with diameters of the same order (1.68–2.54 nm).

Two-dimensional (2D) MoS2-nanosheet (NS) incorporated within electrospun PVA nanofibers: Fabrication and characterization study

In this study, with the help of grinding and sonication, the bulk state of molybdenum disulfide was transformed into a two-dimensional sheet, and composite nanofiber consisting of molybdenum disulfide MoS2/polyvinyl alcohol (PVA) has been successfully developed via electrospinning process. X-ray diffraction (XRD) pattern showed the preferred orientation along the (002) plan of The MoS2 nanosheet. Rietveld refinement was applied to obtain the microstructure parameters of the MoS2. The formation of S-S and Mo-S bonds in MoS2 was confirmed by the Fourier-transform infrared spectroscopy (FTIR). FE-SEM images reveal the surface morphology of MoS2 nanosheets, which typically exhibit a flat and layered structure resembling stacked atomic layers of MoS2 two-dimensional nature.In contrast, the MoS2/PVA fibers display a uniform, interconnected nanofiber network with a distinct random formation. Also, Atomic Force Microscopy (AFM) images show the formation of the uniform MoS2/PVA nanofibers, and the evaluated root mean square (RMS) roughness values for PVA and MoS2/PVA fibers are 250 nm and 277 nm, respectively. To elucidate the elemental composition of the MoS2 nanofibers, Energy Dispersive X-ray Spectroscopy (EDX) analysis was performed, confirming the presence of molybdenum and sulfur in the compound. Finally, diffuse reflectance spectroscopy (DRS) was applied to study the optical properties of the MoS2/PVA composite. In addition, the measurement of the contact angle shows that the surface of the nanofibers is hydrophilic, and the amount of hydrophilicity decreases by adding MoS2 nanosheets.

Dynamic responses and damage/element composition analysis of thermoplastic polyamide reinforced epoxy composites exposed to HCI environment

AbstractThe present study aimed to examine how the corrosive environment affected the low‐velocity impact (LVI) characteristics and damage mechanisms of thermoplastic polyamide fiber‐reinforced polymer (PFRP) composites. In this regard, composite specimens were subjected to corrosive environment containing 10 wt.% diluted HCl for one week and one month before LVI tests. To investigate the hostile effects of the corrosive environment on the composites, scanning electron microscope (SEM) coupled with energy‐dispersive X‐ray system (EDX) analyses were carried out, and thus variations in the elemental composition and damage mechanisms for the composites were determined. According to the examinations, it was discovered that the degradation in LVI responses, such as contact stiffness, bending stiffness, and peak force, increased with longer aging time, as expected. Furthermore, when the aging effect was assessed based on absorbed energy, the specimens exposed to a corrosive environment for one month exhibited the highest energy absorption compared to the control and 1‐week‐immersed ones. The degrading effect of the HCI environment appeared as higher damage severity on the composites, which was also detected from the SEM images. According to the SEM analyses, matrix cracks, corrosion pits, and local surface imperfections caused by ion exchange are detected in 1‐week‐immersed specimens, while more serious damage mechanisms such as fiber breakage and fiber pull‐out are noted in specimens exposed to corrosive environment for 1 month. Furthermore, approximately 6.33 wt.% CI was identified in the composites after 1 month of aging, which was associated with the hydrolysis triggered by rise in the composite's damage severity.Highlights Aging effects in mechanical properties of PFRP composites were investigated LVI tests were conducted to determine dynamic responses of aged composites Longer aging time led to more severe damages such fiber rupture, delamination etc. PFRP composites absorbed at least 68% of impact energy.

Characterizing the Stoichiometry of Individual Metal Sulfide and Phosphate Colloids in Soils, Sediments, and Industrial Processes by Inductively Coupled Plasma Time-of-Flight Mass Spectrometry.

Size and purity of metal phosphate and metal sulfide colloids can control the solubility, persistence, and bioavailability of metals in environmental systems. Despite their importance, methods for detecting and characterizing the diversity in the elemental composition of these colloids in complex matrices are missing. Here, we develop a single-particle inductively coupled plasma time-of-flight mass spectrometry (sp-icpTOF-MS) approach to characterize the elemental compositions of individual metal phosphate and sulfide colloids extracted from complex matrices. The stoichiometry was accurately determined for particles of known composition with an equivalent spherical diameter of ≥∼200 nm. Assisted by machine learning (ML), the new method could distinguish particles of the copper sulfides covellite (CuS), chalcocite (Cu2S), and chalcopyrite particles (CuFeS2) with 75% (for Cu2S) to 99% (for CuFeS2) accuracy. Application of the sp-icpTOF-MS method to particles recovered from natural samples revealed that iron sulfide (FeS) particles in lake sediment contained ∼4% copper and zinc impurities, whereas pure pyrite (FeS2) was identified in hydraulic fracturing wastewater and confirmed by selected area electron diffraction. Colloidal mercury in an offshore marine sediment was present as pure mercury sulfide (HgS), whereas geogenic HgS recovered from an industrial process contained ∼0.08 wt % silver per Hg, enabling source apportionment of these colloids using ML. X-ray absorption spectroscopy confirmed that Hg was predominantly present as metacinnabar (β-HgS) in the industrial process sample. The determination of impurities in individual colloids, such as zinc and copper in FeS, and silver in HgS may enable improved assessment of their origin, reactivity, and bioavailability potential.

Alternatywne podejście do usuwania/odzyskiwania wybranych metali z wody kopalnianej wypływającej z zalanej kopalni syderytu Nižná Slaná

The objective of this work was the application of innovative method for metals recovery from metalliferous mine water released from the flooded siderite ore deposit Nižná Slaná. Although the metals contained in mine drainage are considered environmental pollutants, they may also be recognised as valuable resources. Several techniques can be used to obtain them by precipitation. Conventional processes using alkaline reagents produce huge amounts of mixed sludge with appropriate storage and management requirement, void of possibility of individual metals subsequent processing. This study examined the feasibility of Fe and Mn selective retrieval from real mine water. After oxidation and partial precipitation of iron using hydrogen peroxide, precipitation by sodium hydroxide was applied to the residue iron removal from mine water. In the next step potassium permanganate was used to eliminate manganese by oxidative precipitation. ORP and pH values of processed mine water was recorded in the course of oxidation/precipitation processes. The morphology and elemental composition of obtained products were studied by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). The recovery efficiencies of Fe and Mn from mine water reached 99.87 % and 99.25%, respectively. Target metals were removed with high selectivity to levels that comply with environmental requirements.

Features of the iron determination in dust emissions of gas purification of electrometallurgical production

Features of the iron determination in dust emissions of gas purification at electrometallurgical facilities are considered. The elemental and phase compositions of dust emissions were determined using energy dispersive x-ray fluorescence analysis (EDXRF) and inductively coupled plasma atomic emission spectrometry (ICP-AES). Sample preparation conditions were optimized with allowance for the analytical methods used. The phase composition of dust emissions represented mainly by zincite, zinc ferrite, halite and sylvite was preliminary determined by X-ray phase analysis. Model mixtures were prepared and used to construct calibration dependences taking into account the results of diffractometric studies. A technique for rapid x-ray fluorescence determination of iron in dust emissions of gas purification has been developed. The methods for iron determination tested on real samples of dust emissions of electrometallurgical production demonstrated a satisfactory convergence of the results obtained by EDXRF (Sr = 1.3%) and ICP-AES (Sr = 2.6%).

A Direct Route to closo‐SB n Cl n Thiaboranes from Simple Electron‐Precise Synthons: The Different Role of Chalcogen Bonding in SB5Cl5 and SB11Cl11 Crystals

Six‐vertex closo‐SB5Cl5 (1) and ten‐vertex closo‐1‐SB9Cl9 (2) thiaboranes have been prepared, besides the already known 12‐vertex closo‐SB11Cl11 (3), from the co‐pyrolysis reaction of B2Cl4 with S2Cl2 at 280 ºC in vacuo. The compounds are sublimable, off‐white solids. Their elemental composition has been determined by high‐resolution mass spectrometry. They were further characterized by one‐ and two‐dimensional 11B‐spectroscopy and X‐ray structure determination for 1 and 3. Ab initio/GIAO/NMR computations support octahedral, bicapped square‐antiprismatic, and icosahedral geometries for 1, 2 and 3, respectively, as expected based on their closo‐electron counts. 1 is the first isolated example of a neutral polyhedral closo‐thiaborane with a cluster size smaller than ten vertices. The solid‐state structure of 3 is one of the rare examples of a single‐crystal X‐ray structure determination of an icosahedral heteroborane reported. The corresponding crystal‐packing forces show the different role of chalcogen bonding in these octahedral and icosahedral crystals. In addition, there is a mass‐spectroscopy evidence for the recurrent formation of further thiaborane homologs of closo‐SBnCln with n = 4, 6, 10, and supra‐icosahedral 12.

Quantification of the provenance contribution and sedimentary mixing effect of sediments in the Yellow River Basin, China

Quantifying the source contributions of sediments in large fluvial systems with active wind erosion problems has crucial implications for understanding morphological evolution and ecological progression in the Earth system. Much effort have been focused on characterizing sediments of the Yellow River, but quantitation of the sediment source proportions at the basin-wide scale is lacking. To this end, the research aims to quantitatively elucidate the potential source contributions of sediments in the Yellow River based on geochemical characteristics and sediment fingerprinting technique, in order to identify sedimentary mixing effect and propose sustainable development strategies. In total, samples of four source groups (n = 107) and target floodplain sediments (n = 61) were collected and tested for elemental composition, grain size, magnetic susceptibility, and quartz grain microtextures. The results indicated that the optimal tracer combination was determined as P, Zn, and Ca. The average contributions of the “Tibetan Plateau”, “Sandy deserts-Loess Plateau”, “Loess Plateau”, and “Loess Plateau-Qinling Mountains” source groups to the target sediments were 23.0 %, 21.5 %, 31.6 %, and 23.9 %, respectively. The accuracy of source apportionments was supported by the goodness of fit (GOF) and virtual mixtures tests. Meanwhile, large amounts of debris from surrounding mountains was transported to the Loess Plateau through fluvial processes and ultimately mixed with aeolian deposits, leading to sedimentary mixing effect. To maintain water balance and minimize erosion risk, the drought-resistant perennial planting and moderate grazing were recommended. The findings are instrumental in promoting soil and water conservation and disclosing fluvial and aeolian interaction on a global scale.

Multiple Ba Phases in Marine Sediments elucidate environmental processes and conditions for the Holocene Mediterranean

Mediterranean sediments are known for their major shifts in sedimentary composition associated with dramatic changes in environmental and climate conditions. A typical expression for this in Holocene sediments is the occurrence of a distinctly organic-rich unit, sapropel S1, thought to be related with humid climate conditions. The S1 is accompanied by major changes in Ba content and in other elemental composition, respectively related to biological upper water column productivity and shifts in detrital sediment provenance. Here, we focus on changes in Ba and in its various phases to unravel shifts in environmental conditions around S1.Using selective extractions for sediments in cores MP37PC, MP39PC and MP50PC, respectively at 1908, 1359 and 775m water depth, we distinguish different Ba-phases: detrital Ba (Ba-det), barite Ba (Ba-bar), Mn-oxide-related Ba (Ba-ox), carbonate- and pyrite-associated Ba (Ba-carb and Ba-pyr). The predominant Ba-phase during S1 is Ba-bar (∼70%), whereas before and after S1 it is Ba-det (>90%). All other phases are mostly relatively small but have diagnostic value for environmental conditions and processes.The detrital (Ba/Al) is distinctly lower during S1 than before and after. The (Ba/Al). det variability, and enhanced values for Ba-carb and Ba-ox may have substantial influence on the traditional way to derive barite-Ba or excess-Ba content.The steep gradients in Ba-bar at onset and ending of S1and its high level during S1, clearly identify this period. In addition, and due to the exclusive nature of extraction results, we unequivocally demonstrate for the first time that there is a small gradual ‘early onset’ Ba-bar preceding the major increase in sapropel S1 formation sensu stricto.The ending of S1 formation is relatively abrupt with a well-defined reventilation event (’6 ka reventilation event’). This reventilation is associated with a rapid change in environmental conditions such as oxygenation and related remineralization of organic matter and recrystallization of carbonate. This rapid change and associated diagenetic processes are authentically recorded in Ba-carb and Ba-ox. For the period during sapropel S1 formation, the Ba-carb and Ba-ox results point to different levels of ventilation in the Eastern Mediterranean, i.e. a relatively mixed water mass down to ∼800m, a moderately mixed water mass from ∼800-to ∼1500 m, and a more stagnant water mass below 1500 m.

Green synthesis of zinc oxide nanoparticles using Rhus coriaria extract and their anticancer activity against triple-negative breast cancer cells

The growing interest in using plant extracts for the biogenic synthesis of zinc oxide nanoparticles (ZnO NPs) stems from their facile, eco-friendly, and biologically safe approach instead of chemical routes. For the first time, ZnO NPs were successfully biosynthesized using Rhus coriaria fruit aqueous extract as a reducing and capping agent. Characterization revealed that the biosynthesized ZnO NPs possessed a maximum absorbance of approximately 359 nm and closely resembled the hexagonal ZnO wurtzite crystalline structure, with an average crystalline size of 16.69 nm. The transmission electron microscope (TEM) showed the presence of spherical and hexagonal morphologies, with an average grain size of 20.51 ± 3.90 nm. Moreover, the elemental composition of the synthesized ZnO NPs was assessed via energy-dispersive X-ray spectrometry (EDX), and the presence of phytocompounds on their surface was subsequently verified through FT-IR analysis. The ζ-potential of ZnO NPs was recorded at − 19.9 ± 0.1663 mV. Regarding anti-cancer properties, ZnO NPs were found to possess potent anti-tumor effects on MCF-7 and MDA-MB-231 breast cancer cells. Their efficacy was dose-dependent, with IC50 values ranging from 35.04–44.86 μg/mL for MCF-7 and 55.54–63.71 µg/mL for MDA-MB-231 cells. Mechanistic studies in MDA-MB-231 cells revealed apoptosis induction, validated by DAPI staining, confocal microscopy, and Annexin V/PI staining, showing apoptosis by 12.59% and 81.57% at ½ IC50 and IC50 values, respectively. Additionally, ZnO NPs were observed to provoke S-phase arrest and inhibit colony-forming and metastatic potential by modulating apoptosis and metastasis-related genes. This study unravels new insights into how ZnO NPs provoke cancer cell death and inhibit metastasis, revealing new prospects in cancer nanotechnology.

Reproductive Response of Platynothrus peltifer (C.L. Koch, 1839) to Continuous Nitrogen Deposition

Continuous nitrogen deposition threatens ecosystems by acidifying soils, causing a stoichiometric imbalance in the vegetation and ultimately, the disappearance of plant and animal species. There is a gap in knowledge of how decomposers such as oribatid mites cope with the effects of nitrogen deposition. Therefore, we conducted feeding experiments with the herbivorous mite Platynothrus peltifer (C.L. Koch, 1839) to assess its fitness as a measure of its reproductive response towards different nitrogen levels in its diet. Mites were collected from the field, starved, and allowed to lay eggs. We recorded the number of eggs during 60 days of experimental trial. The fecundity of mites varied with different elemental compositions, whereby phosphorus seemed to be a limiting factor. With ongoing nitrogen deposition in the future and concomitant phosphorus limitation, we expect a negative impact on the population dynamics of herbivorous decomposers such as Platynothrus peltifer.

Multiwalled carbon nanotubes supported Fe nanostructured interfaces for electrochemical detection of uric acid

Uric acid (UA) levels in biological fluids are an important diagnostic and prognostic biomarker for various metabolic disorders. Therefore, a convenient, facile, one-step electroreduction method to develop Fe nanostructured (FeNS) interfaces for highly sensitive electrochemical detection of UA. The synthesis process was thoroughly investigated at various deposition potentials, pH of the electrochemical bath solutions, and growth durations to attain excellent electrochemical response towards UA detection. The morphology and elemental composition of the FeNS/MWCNT were analyzed using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDXS) techniques. We observed uniform deposition of FeNSs with sizes ranging from 100 − 120 nm on tubular nanostructures. The multiwalled carbon nanotubes supported Fe nanostructured interfaces (FeNS/MWCNT) generated at a potential of –1.1 V demonstrated excellent electrochemical response towards UA with a wide linear detection range of 5 to 500 µM with a sensitivity of 6.5605 µA µM−1 cm−2 and low detection limit of 3.26 µM. The excellent electrochemical response was attributed to the synergistic effect of MWCNTs, which facilitated FeNSs growth, leading to increased active sites for electrocatalysis and sensitive detection of UA. The convenience of the synthesis process, tunable electrochemical response, and reliability of the detection process make FeNS interfaces a potential option for developing electrochemical UA sensors.

Lost-wax casting: A widespread technique to produce copper alloy adornments in Atlantic Europe since the mid-second millennium BC

Lost-wax casting is a metalworking technique that has long been regarded as an innovation imported from the eastern Mediterranean and only widely used in Western Europe since the Late Bronze Age. We now have evidence that this technique was in fact largely in use from the Middle Bronze Age onwards for the production of copper alloy adornments in the Atlantic area. Along with palstaves, these objects are the most abundant in Atlantic hoards from the 15th to the 13th centuries BC. Thanks to detailed morphological and technological study, combined with an experimental approach and analysis of their elemental composition, we can propose new chaînes opératoires for the manufacture of massive annular bracelets with geometric decoration.

Chemical characterization of submicron particulate matter (PM1) and its source apportionment using positive matrix factorization

AbstractThe present study was conducted to address four key questions: (i) What are the levels of submicron particulate matter at the study area?, (ii) which are the major contributing sources of these particles?, and (iii) is there any seasonal changes in the levels of pollutants at the study site? Thus, the study was conducted at an urban residential site of Jaipur City, India, to determine the elemental and ionic composition of toxic elements associated with PM1 using inductively coupled plasma optical emission spectroscopy and ion chromatography to reveal specific sources. Monitoring was done for a period of 8 months between October 2020 and May 2021 considering three seasons: winter (December–February), pre‐monsoon (March–May), and post‐monsoon (October–November). PM1 samples were found to be highly enriched with Ag, Cd, B, Ni, and Zn. PM1 mass concentrations were observed to be greater in winter (104.13 ± 30.16 µg m−3) and lower in the pre‐monsoon season (83.62 ± 19.40 µg m−3). Ion concentrations (Cl−, NO32−, and SO42−) followed a similar pattern to PM1 concentrations. Source apportionment by positive matrix factorization at the study site revealed six major sources of pollutants (soil dust, agro‐based industry, automobile industry, salt aerosols, industrial activities, and biomass burning).

Physicochemical analysis of deterioration affecting the darkening of rock art in Maros-Pangkep, South Sulawesi, Indonesia

This study investigates the darkening processes affecting Maros-Pangkep rock art through a comprehensive multianalytical approach. We integrate in-situ color index measurements using Nix color Pro 2 with various physicochemical characterization techniques, including optical microscopy, XRF, SEM-EDS, Raman spectroscopy, and FTIR. By examining microbial, geochemical, and anthropogenic factors on rock art pigment samples, we establish a clear correlation between the formation of blackish-gray layers and reduced chromaticity values, indicating a significant darkening process. The shift in pigment color from vibrant red or purple to a prevailing blackish-gray hue is attributed to surface accumulation. Surface morphology analysis reveals distinct blackish deposits and delicate white fibrous structures on darkened rock art. Elemental composition analysis demonstrates heightened blackish deposit formation and increased phosphorus content in darkened samples. SEM-EDS characterization exposes gypsum morphology, with filament-like structures prevailing in heavily darkened samples, highlighting the role of both geochemical and microbial factors in deposit layer formation. FTIR spectra results confirm the presence of gypsum minerals, which are attributed to the substrate minerals and/or mineral weathering product, and unveil the existence of organic compounds, indicating microbial activity. Additionally, Raman spectroscopy reveals the anthropogenic contribution, notably soot deposition produced by human activities, to the darkening of rock art. This study underscores the need for a holistic preservation approach addressing natural, human, and microbial impacts on cultural heritage sites. Further research is also needed to conduct cross-sectional stratigraphical analysis to understand the accurate mechanism of the deterioration process on the rock art. Moreover, excavation measures regarding the possible relationship of soot deposition with human activities are also important to be carried out at the sites.

Green synthesis of carbon dots from mangosteen peel for fluorescent cancer cells

Recently, carbon dots (CDs) have received significant attention owing to their outstanding optical properties, good solubility, and low toxicity. In this research, CDs were synthesized by a hydrothermal method based on an environmentally friendly and straightforward strategy, using only mangosteen peel and deionized water. The synthesized CDs had an average size of 3.09 ± 0.38 nm. The absorbance spectrum peak for the CDs was seen at 282 nm, and the central wavelength of fluorescence emission was observed at 433 nm under an excitation wavelength of 355 nm. An aqueous solution of CDs exhibited bright green fluorescence when observed with the naked eye under UV irradiation. Both Fourier transform infrared and X-ray photoelectron spectroscope measurements were taken to determine the elemental compositions of the organic substance functional groups on the surface of the CD, such as hydroxyl, carboxyl, and carbonyl groups. These functional groups originate the different emission centers leading to multicolor fluorescent emissions. Furthermore, the synthesized CDs were found to have good biocompatibility with organic and biological materials. The remarkable properties of CDs, including their nanoscale dimensions, strong multicolor fluorescent emissions, non-toxicity, and excellent cell compatibility, could effectively permeate the cell membrane, cytoplasm, and nucleus and provide fluorescence emission. This suggests a significant potential for CDs in fluorescent cell staining applications. Finally, the CDs were used as a fluorescent dye for human colon cancer cells, as they exhibited excellent fluorescence for cell staining.

Convolutional neural network based methodology for flexible phase prediction of high entropy alloys

ABSTRACT The advent of high entropy alloys has created a design space that is unfeasible to explore solely through experimentation, thus necessitating the use of computational methods, such as artificial neural networks. This study proposes a new architecture utilizing a convolutional layer to extract relevant elemental features from the alloy composition without limiting the model to specific elements by treating the elemental composition of the high entropy alloy in a similar manner to a row of pixels, using relevant elemental properties in lieu of color values. This convolutional model was able to predict the crystal structure of solid solutions in a high entropy alloy composition with an accuracy of 89.3% in a six-way classification and the formation of intermetallics with an accuracy of 91.4% during holdout validation, while being capable of accurately predicting the primary crystal structure of high entropy alloys containing elements the model was not trained on. Significant space still exists for further experimentation and improvement with this methodology, including augmenting the available datasets and implementation of additional convolutional layers. Due to the limited interpretability of the model architecture, care should be taken when inferring trends from the model prior to validation through experimental, or well-established computational methods.

Colchicine-capped ZnO nanoparticles: Elucidation of their cytotoxicity potential against MDA-MB 231 cancer cells

This research descibes a pioneering approach aimed at preparing zinc oxide nanoparticles (ZnO-NPs) with colchicine as the reducing and capping agent. Colchicine-loaded ZnO-NPs (CHZnO-NPs) were prepared by adding colchicine to the zinc sulfate heptahydrate solution. The CHZnO-NPs formulation was then characterized to determine the morphology, size, crystallinity, elemental composition and vibrational properties. Upon characterization, CHZnO-NPs were studied for their cytotoxic effect against the breast cancer cell line (MDA-MB-231). The successful biosynthesis of CHZnO-NPs was initially confirmed visually by the changes in the mixture color, from light-yellow to white cloudy. The best CHZnO-NPs formulation selected was F3, which possessed 10 mg/mL of colchicine. Formulation (F3) had the smallest mean particle diameter of 43.77 nm and the lowest zeta potential of −19.60 mV. It also had 92.21 ± 0.012 % encapsulation efficiency and 20.86 ± 0.005 % drug loading. Formulation (F3) displayed a hexagonal wurtzite structure with irregular morphology. The observation of colchicine peaks on the FTIR spectra of F3 proved the role of colchicine as a reducing and capping agent during the synthesis of ZnO-NPs. Besides, the in-vitro cell cytotoxicity study on the MDA-MB-231 cell line revealed a significant reduction in cell proliferation at the concentration of 25 μg of colchicine and F3. Further, studies on the cellular migration potential also demonstrated concentration-dependent activity. Overall, CHZnO-NPs were shown to be successfully synthesized via an environmental-friendly procedure and colchicine acted as a capping agent to regulate the particle size, and aggregation, in addition to its anticancer properties.

Crystal chemistry and ionic conductivity of garnet-type solid-state electrolyte, Li5-xLa3(NbTa)O12-y

Crystal structures, microtopography, morphologies, elemental compositions, and ionic conductivity have been investigated for Li5-xLa3(Nb,Ta)O12-y using X-ray diffraction (XRD), field-emission analytical scanning and transmission electron microscopies (S/TEM), and electrochemical impedance spectroscopy. Using Rietveld refinements with powder XRD patterns, we determined that the number of Li atoms in the formula is less than 5 and that Li5-xLa3(NbTa)O12-y crystallizes in the cubic garnet structure with a space group Ia-3d. Sintering at varying temperatures (750–1000 °C) for 5 h in an ambient atmosphere produced distinct outcomes. Rietveld refinements disclosed that the sample sintered at 1000 °C (Li3.43(2)La3Nb1.07(2)Ta0.93(2)O12-y, a = 12.8361(7) Å, V = 2114.96(3) Å3) exhibited the highest ionic conductivity, while the 850 °C sample had the lowest conductivity, characterized by lower Li concentration and impurity phases (Li(Nb,Ta)3O88, Li2CO3). Analyses, including XRD and electron microscopy, confirmed the 1000 °C sample as a relatively phase pure with enhanced Li content (Li/La = 1.2), larger grains (15 μm), and uniform crystallinity. The 1000 °C sample introduced additional partially filled Li3 (96h) sites, promoting Li migration, and enhancing ionic conductivity. The resulting XRD pattern at 1000 °C has been submitted to the Powder Diffraction File as a reference.

Mapping the elemental distribution in archaeological findings through advanced Neutron Resonance Transmission Imaging

This work highlights recent application of energy-selective neutron imaging at the ISIS Neutron and Muon Source, specifically focusing on the development of Neutron Resonance Transmission Imaging (NRTI) at the INES instrument. NRTI is a nuclear technique based on resonant neutron absorption reaction, which combines the sensitivity to elemental and isotopic composition with detailed morphological information, using the epithermal portion of the neutron flux available on the INES instrument at the ISIS facility. Unlike standard neutron radiography and tomography methods, NRTI preserves detailed time and energy information for each detector pixel, enabling enhanced visualisation of elemental distribution inside an object’s volume, with the potential for quantitative elemental analysis. These features combined with the non-destructiveness of NRTI make the method promising for applications in the field of Cultural Heritage, especially when it is employed in a multi-technique approach to provide complementary information about the composition and the crystalline structure of archaeological artefacts. A study related to Heritage Science is presented to demonstrate the effectiveness of NRTI in non-destructive investigations of inhomogeneous artefacts, specifically focusing on the excavation finds related to the first evidence of ancient brass production in Milan, Italy, during Roman times.