Determination Of Elemental Composition Research Articles

Green synthesis of NiFe2O4 nanoparticles and evaluation of their photocatalytic activities

Studies on the potential applications of nanoparticles (NPs) synthesized by biological methods attract the attention of researchers. First time in this study, photocatalytic activities of NiFe2O4 NPs synthesized with pomegranate fruit peel extract were determined against brilliant blue. Surface charge and dynamic size of NPs were detected at −11 mV, and 405 nm, respectively. According to scanning electron microscopy images, NiFe2O4 NPs have spherical morphology with a diameter of 75 nm. Energy dispersive X-ray spectroscopy, X-ray diffraction, and Fourier transform infrared spectroscopy were used for the determination of elemental composition, crystallinity, and functional groups of NPs, respectively. As a result, it was determined that NiFe2O4 NPs were effective for remediation (65%, for 3 h) of dye. The catalytic activity of NiFe2O4 NPs refers to the Fenton mechanism.

Quality index for Martian in-situ laser-induced breakdown spectroscopy data

Laser-induced breakdown spectroscopy (LIBS) has been widely implemented in Mars explorations as a versatile technique for in-situ chemical analysis. Determination of elemental composition from Martian LIBS typically relies on uni/multi-variate models trained on specific laboratory datasets, which in turn requires similarities between this training dataset and Martian data. However, plasma excitation can affect this similarity. The inability to identify insufficiently excited data may ignore poor focusing for some observations or lead to unawareness of compositional uncertainty. This study establishes the LIBS Quality Index (LQI) for Martian LIBS data quality by evaluating the carbon ionic doublet emission around 658 nm for the Martian atmosphere, assessing its signal-to-noise ratio as well as its deviation from the line profile standard of the instrument-specific laboratory dataset. This method allows the LQI to be used as a confidence level for assessing LIBS excitation quality and measurement for similarity with instrument-specific laboratory datasets. The LQI evaluation routines were established for ChemCam, MarSCoDe, and SuperCam. Validation of LQI was carried out on the laboratory datasets and Mars data with known quality assessments of the three instruments. The index was verified to be sensitive to input irradiance, applicable with three current Mars LIBS instruments, robust against various material types (except carbonate), and moderate interference from H, Fe, and Ti. Applying the LQI, the study was able to identify the remote micro-imager (RMI) autofocus as an optimal mechanism, to discover the influence of environmental conditions on data quality, to discuss the impact of target material consolidation and morphology on data quality, and to investigate the contribution of data quality to quantification uncertainty. These application examples demonstrated the feasibility of LQI as a useful and sensitive tool to assess data quality and its potential to aid current and future Martian LIBS explorations.

Physical decomposition stage and ergosterol content predict the chemical composition of downed dead wood in Mediterranean dehesas

AbstractDead wood is a key substrate of forests that plays an important role in fertility and productivity. However, dead wood is scarce in traditionally managed forests like Mediterranean dehesas. The chemical composition of downed dead wood in Quercus pyrenaica dehesas was analysed in different physical decomposition stages as a proxy of dead wood decay length. We also assessed the contribution of fungal activity, by quantifying ergosterol, to the chemical composition of deadwood. Chemical analyses included elemental composition determination, thermogravimetry and infrared spectroscopy. Our results showed that both the physical decomposition stage and ergosterol content extensively predicted the chemical composition of Q. pyrenaica dead wood decay processes under field conditions. The physical stage was a better predictor of the C/P ratio and polysaccharides proportion, while ergosterol better predicted P content and the N/P ratio. In other cases like lignin, the relation between ergosterol content and chemical composition varied depending on the physical stage. In addition, environmental local factors differentially affected chemical composition across physical decomposition stages. We conclude that the physical decomposition stage and ergosterol content complementarily contribute to estimate the temporal behaviour of the chemical composition of dead wood in Mediterranean areas. Moreover, we recommend using the FT-IR analysis to assess the nature of temporal chemical changes in downed dead wood. Finally, our study claims to consider the potential impact of local environmental factors, such as air temperature and relative humidity, on dead wood decay processes in traditionally managed forests in the current global change scenario.

Critical evaluation of energy dispersive X-ray fluorescence spectrometry for multielemental analysis of coffee samples: Sample preparation, quantification and chemometric approaches

In the present contribution, a critical evaluation of the use of EDXRF (Energy dispersive X-ray fluorescence spectrometry) for elemental composition determination (K, Ca, Mn, Fe, Cu, Zn, Sr and Rb) of coffee samples is presented. Firstly, several sample treatment procedures (pressed pellets and loose powder) and quantification strategies (fundamental parameters and empirical calibration) were evaluated.In addition to quality and nutritional purposes, information of elemental content in coffee samples can be also useful for coffee traceability and provenance studies. In view of that, a comparison of different tools such as explorative principal component analysis (PCA) and classification by partial least square regression (PLS-DA) were also tested as discriminating tools of different types of coffee samples (i.e., pure, instant and coffee with additives). Chemometric analysis was performed using coffee elemental concentrations determined by the developed EDXRF method and, for the first time, using raw EDXRF spectra obtained, without the need of a fitting and quantification procedure.

Determination of Elemental Composition of Soils Collected near Waste Incineration Plants in Moscow Using Neutron Activation Analysis

Determination of Elemental Composition of Soils Collected near Waste Incineration Plants in Moscow Using Neutron Activation Analysis

ANÁLISE DE FRAGMENTOS BALÍSTICOS POR MEIO DE EXAMES MICRO BALÍSTICOS, DETERMINAÇÃO DA COMPOSIÇÃO QUÍMICA E ANÁLISE ISOTÓPICA DO CHUMBO: UMA REVISÃO

BALLISTIC FRAGMENTS ANALYSIS BY MICRO BALLISTIC EXAMINATIONS, CHEMICAL COMPOSITION AND LEAD ISOTOPE RATIOS: A REVIEW. Firearms and ammunition identification produces important information for the elucidation of the crime and also in cases of confirmation of the offender. In a crime scene, when a suspect weapon and its ammunition are found, it is possible to clarify and conclude an investigation using qualitative analysis and standards. However, in some cases only the fragments of ammunition are found, which makes difficult to identify the weapon using traditional techniques. Therefore, alternative methods are needed such as the determination of elemental composition of the lead alloy and the verification of the lead isotopic ratios. The present work includes a review of the basic concepts of ballistics and conventional techniques of ballistic confrontation, the existing studies related to the chemical analysis of ballistic fragments and its application in criminalistics and, finally, the articles involving the lead isotopic analysis as a tool for ballistic identification.

OPEs-ID: A software for non-targeted screening of organophosphate esters based on liquid chromatography-high-resolution mass spectrometry

Organophosphate esters (OPEs) are widely used as flame retardants and plasticizers, presenting a potential threat to the environment and human health. To date, no automatic software exists for the nontargeted screening of OPEs. In this study, OPEs-ID, a user-friendly software, was developed for the identification of OPEs using liquid chromatography-high-resolution mass spectrometry. The main workflow of OPEs-ID included fragments-dependent precursor ion screening, elemental composition determination, extracted ion chromatograms (EIC) comparison, and molecular structure identification via MetFrag strategy. A mixture of 17 OPE standards was identified with an identification rate of 100% by OPEs-ID. OPEs-ID demonstrated a rate of 94.1% for correctly ranking within the top 1 candidate in a local database (41.2% in PubChem) for the 17 OPE standards, which remarkably improved the identification when compared to conventional in silico fragmentation algorithms. Using a pooled airborne fine particle sample (PM2.5), OPEs-ID could automatically retrieve 22 valid molecules with structure candidates. The detection frequencies of 9 newly identified OPEs were between 13% and 100% in the 32 PM2.5 samples. Their semi-quantification concentrations were comparable to those of some traditional OPEs. Overall, OPEs-ID offers a powerful tool to significantly enrich our understanding of the OPEs present in the environment.

Evaluation of the recycling potential of obsolete mobile phones through secondary material resources identification: A comprehensive characterization study

The growing concern over the management of e-wastes has generated an interest in the recovery of resources from these wastes under the concept of urban mining and circular economy. However, in the absence of accurate knowledge of the physico-chemical compositional structure of these wastes makes the recycling process difficult. Thus, the present study conducted a recycling-oriented characterization of waste mobile phones (WMPs) for the identification of secondary materials and estimated their recycling potential. The characterization was performed using ICP-OES and FTIR techniques after dismantling WMPs for the determination of elemental composition and the polymeric fractions respectively. Dismantling of the WMPs revealed that enclosures, batteries, display modules, and PCBs consist of 35.33 wt%, 28.9 wt%, 19.44 wt%, and 16.31 wt% respectively. Of these components, PCBs constitute the highest economic recovery potential with an estimated potential revenue generation of more than 50,000 US $ per ton of waste PCBs. Copper showed the highest recovery potential (234.39 tons/year) with an economic value of approximately 3317 US $/ton of WPCBs followed by Sn (27.37 tons/year) and Ni (24.64 tons/year). Among different precious metals, Au was found to have the highest percentage of economic value (76.22%) followed by Pd (8.16%) and Ag (3.13%). The display modules and enclosures were found to have relatively lower contributions than WPCBs in the overall recycling potential due to lower metal contents and mixed polymeric fractions. The findings in the study indicate that WMPs could serve as a promising new source for sustainable secondary mining of rare and valuable metals. Further, the study will help the policymakers in designing effective e-waste management strategies through the promotion of sustainable recovery of materials.

Determination of Elemental Composition and Content in Stream Sediments by Laser-Induced Breakdown Spectroscopy

Determination of Elemental Composition and Content in Stream Sediments by Laser-Induced Breakdown Spectroscopy

Mechanical and Biocompatibility Properties of 3D-Printed Dental Resin Reinforced with Glass Silica and Zirconia Nanoparticles: In Vitro Study.

This study aimed to assess the mechanical and biocompatibility properties of dental resin reinforced with different nanoparticle additives. Temporary crown specimens were 3D-printed and grouped based on nanoparticle type and amount, including zirconia and glass silica. Flexural strength testing evaluated the material's ability to withstand mechanical stress using a three-point bending test. Biocompatibility was tested using MTT and dead/live cell assays to assess effects on cell viability and tissue integration. Fractured specimens were analysed using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) for fracture surface examination and elemental composition determination. Results show that adding 5% glass fillers and 10-20% zirconia nanoparticles significantly improves the flexural strength and biocompatibility of the resin material. Specifically, the addition of 10%, 20% zirconia, and 5% glass silica by weight significantly increases the flexural strength of the 3D-printed resins. Biocompatibility testing reveals cell viabilities greater than 80% in all tested groups. Reinforced 3D-printed resin holds clinical potential for restorative dentistry, as zirconia and glass fillers have been shown to enhance mechanical and biocompatibility properties of dental resin, making it a promising option for dental restorations. The findings of this study may contribute to the development of more effective and durable dental materials.

Potential Usage of Selected Agro-Residue as a Biofuel Production Sources: Physiochemical Evaluation Approach

This article present physiochemical characterization of commonly available agricultural waste residues on dry basis for: (Corn cob, Coconut shell, Cashew nut, Palm kernel shell and Cassava stem) with the view to evaluate their respective suitability for biofuel production using thermochemical conversion process. The investigated respective biomass feedstock milled samples was analyzed in the laboratory for fuel physiochemical characterization. The physiochemical characterization carried out on each biomass waste sample are Proximate Analysis, Ultimate Analysis, Elemental composition analysis and determination of their respective Higher heating Value(HHV). The obtained results revealed that of all the biomass samples characterized, the Coconut shell (CNS), Corn cob(CC) and Cassava stem(CS) samples proved to possess the most suitable characteristics for better bio-oil production. Palm kernel shell(PKS), Coconut shell(CNS) and Cashew nut(CN) due to their obtained low ash content, adequate hardness and fairly high fixed carbon content are generally regarded to be a potential source for making quality grade charcoal (bio-char) using Pyrolysis process. Gasification process is found desirable to producing high yield of bio-gas for Corncob(CC) and Cassava stem(CS) biomass samples due to their respectively obtainable high value of moisture content: (13.4%wt and 15.10%wt.) and fixed carbon contents of (67.94%wt and 74.13%wt) in this study. Moreover, among all other biomass sample investigated in this study, Coconut Shell(CNS) in comparison to all other samples characterized attained highest HHV of 31.2 MJ/kg. Negligible amount of Sulphur and Nitrogen which could resulted to lower emission of SO2 and NO2 if use directly for heating purposes aftermath application of any of the thermochemical conversion processes is also observed for the biomass waste samples analyzed independent of their types. These results show that the characterized biomass samples could be a suitable candidate for alternative energy fuels production in terms of quality and environment concern.

Optimization of the energy dispersive x‐ray fluorescence spectrometer for determination of elemental composition of air particulate matter samples

AbstractElemental composition of air particulate matter samples was determined by energy dispersive x‐ray fluorescence technique utilizing in‐house constructed secondary target excitation system. The system, based on 3 kW Mo‐anode x‐ray tube with Ni and Mo secondary targets, was operated in air at atmospheric pressure. The sensitivities of the measurement system were determined for a number of elements in the atomic number range from Z = 13 to Z = 39 (K‐series characteristic radiation) and from Z = 44 to Z = 82 (L‐series characteristic radiation). The results of measurement of reference material samples confirmed that the in‐house constructed system is well suited for analysis of air particulate matter deposits on filter substrate with application of the thin‐layer sample model, with sufficiently good detection limits also for low‐Z elements such as Al, Si, P, S, and Cl.

Precise determination of major and trace elements in micrometer-scale ilmenite lamellae in titanomagnetite using LA-ICP-MS technique: application of regression analysis to time-resolved signals.

Laser ablation ICP-MS (LA-ICP-MS) is a powerful microbeam technique capable of rapid and precise determination for a large spectrum of trace elements at ppm or sub-ppm levels. Micrometer-scale minerals and inclusions are very common in geological materials, for which direct measurement is restricted by the spot size using LA-ICP-MS (generally 20-50 μm). In this study, ilmenite lamellae intergrown with magnetite were selected as an example to describe a practical algorithm that applies regression analysis to extract the chemical compositions of binary phases from mixed LA-ICP-MS signals. The method accuracy is confirmed by the agreement between the regressed value for various trace elements in ilmenite exsolutions and their reference values (direct analyses using EPMA and LA-ICP-MS). Results were obtained for most detectable components (Mg, Mn, V, Nb, Ta, Sc, Zr, Hf, Sn, et c.) and their relative deviations are within ±10%, even for those <10 ppm (such as Hf and W). Relative standard errors on the regressed value were calculated to evaluate the precision of the method, which is mostly within 10%, and the worst up to 25%. Therefore, the algorithm described in this contribution provides a solution for precise determination of trace element compositions for micrometer-scale ilmenite lamellae in titanomagnetite using LA-ICP-MS, and is potentially practical for other geological materials.

Fast and green microwave-assisted digestion with diluted nitric acid and hydrogen peroxide and subsequent determination of elemental composition in brown and white rice by ICP-MS and ICP-OES

For the elemental determination of rice, a microwave-assisted sample preparation method employing diluted HNO3 and H2O2 under high temperature and pressure was developed in a rapid and eco-friendly manner. The analysis was performed using inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectrometry (ICP-OES). At 280 °C and 160 bar, the optimal condition for microwave-assisted wet digestion in a single reaction chamber was achieved with a mixture consisting of 3 mL of 0.1 mol L−1 HNO3 and 5 mL of 30% H2O2 (0.25 g rice sample). The optimized procedure yielded a low residual acidity (RA) of 0.017 mol L−1 and low residual carbon content (RCC) of 355 mg L−1. The limits of detection (LODs) were from 0.159 (Sb) to 9.863 (Fe) μg kg−1. Additionally, the developed method received a total score of 85 on the analytical Eco-Scale, indicating an excellent green analysis method. Furthermore, the method was validated by determining 19 elements (Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Ni, P, Pb, S, Sb, Se, and Zn) in brown and white rice cultivated in South Korea.

Deciphering the birth region, formation, and evolution of ambient and transient solar wind using heavy ion observations

This paper outlines key scientific topics that are important for the development of solar system physics and how observations of heavy ion composition can address them. The key objectives include, 1) understanding the Sun’s chemical composition by identifying specific mechanisms driving elemental variation in the corona. 2) Disentangling the solar wind birthplace and drivers of release by determining the relative contributions of active regions (ARs), quiet Sun, and coronal hole plasma to the solar wind. 3) Determining the principal mechanisms driving solar wind evolution from the Sun by identifying the importance and interplay of reconnection, waves, and/or turbulence in driving the extended acceleration and heating of solar wind and transient plasma. The paper recommends complementary heavy ion measurements that can be traced from the Sun to the heliosphere to properly connect and study these regions to address these topics. The careful determination of heavy ion and elemental composition of several particle populations, matched at the Sun and in the heliosphere, will permit for a comprehensive examination of fractionation processes, wave-particle interactions, coronal heating, and solar wind release and energization that are key to understanding how the Sun forms and influences the heliosphere.

Elemental composition and thickness determination of thin films by electron probe microanalysis

Electron probe microanalysis (EPMA) applies to solid samples of homogenous (bulk) chemical composition and can usually not be applied to structures which are inhomogeneous in the micrometer range such as thin film systems down to a few nm. However, in combination with the established thin film software Stratagem, the thickness as well as the elemental composition of thin films on a substrate can be determined. This has been recently successfully demonstrated for Fe‐Ni on Si and Si‐Ge on Al2O3 thin film systems. For both systems five samples of different elemental composition and a reference were produced and characterised by inductively coupled plasma mass spectrometry (ICP‐MS), Rutherford backscattering (RBS), and transmission electron microscopy (TEM) as reference values. Last year, a new and open‐source thin film evaluation programme called BadgerFilm has been released. It can also be used to determine thin film composition and thickness from intensity ratios of the unknown sample and standards (k‐ratios). In this contribution, we re‐evaluated the data acquired for the Fe‐Ni and Si‐Ge systems using the BadgerFilm software package and compared the obtained elemental compositions and thickness values with the results of the Stratagem software and the reference methods. The conclusion is that the BadgerFilm software shows good agreement with the elemental composition and thickness calculated by Stratagem (mostly &lt;2% for both composition and thickness) and with the reference values for two representative thin film systems (&lt;1%–2% for composition and &lt;10%–20% for thickness).

Zinc oxide Nanoparticles, Biosynthesis, characterization and their potent photocatalytic degradation, and antioxidant activities

ObjectivesThis study aimed to biosynthesize zinc oxide nanoparticles (ZnO-NPs) using the seed extract of Moringa oleifera. The catalytic activity of the biosynthesized ZnO-NPs was examined as photocatalyst for the degradation methylene blue (MB) and their antioxidant activity by H2O2 assay were studied. MethodsThe biosynthesized ZnO-NPs and their physicochemical properties investigated via UV–visible spectroscopy (UV–vis), Fourier transform infrared (FTIR) spectroscopy, Transmission electron microscopy (TEM), energy dispersive X-ray (EDX), X-ray diffraction analysis (XRD) analysis, and zeta potential was calculated using the Zetasizer nano. ResultsUV–Visible analysis of the biosynthesized nanoparticles revealed the characteristic a specific peak at 375 nm indicating the formation of ZnO-NPs. XRD study showed a distinctive diffraction peak indicating the formation of crystalline nanoparticles which matches to the spherical and hexagonal structure of ZnO-NPs. TEM results confirmed the formation of spherical and hexagonal ZnO-NPs and the size ranging between 25 and 30 nm. EDX analysis was used for the determination of elemental composition of biosynthesized ZnO-NPs which included zinc, oxygen and carbon. FTIR spectroscopy is useful to determine the available functional group from the phytochemical components implicated in the stabilization and reduction of ZnO-NPs. ZnO-NPs exhibited effective photocatalytic activity in degrading methylene blue (MB) and maximum photocatalytic activity (71 %) after 24 hrs. In addition, ZnO NPs exhibited high antioxidant activity against H2O2 free radicals scavenger. ConclusionThe biosynthesized ZnO-NPs have excellent MB dye degradation power and complete dye degradation was achieved within 24 hrs and synthesized ZnO-NPs showed improved antioxidant power. ZnO-NPs are good tools for industrial applications.

Determination of Saffron Quality through a Multi-Analytical Approach

Currently, the specifications for the assessment of saffron quality are contained in the ISO 3632 technical standard. This norm evaluates saffron quality through a UV-Vis spectrophotometric method and grades the spice into three commercial categories. However, numerous studies have highlighted several weaknesses and limitations of the ISO method. For this reason, a new multi-analytical approach for the determination of saffron quality is proposed in this work. Different techniques were employed to assess saffron quality: UV-visible spectroscopy (UV-Vis), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM-EDX) and inductively coupled plasma—optical emission spectroscopy (ICP-OES). The results show that the commercial grading based on the ISO 3632 methodology is not always in line with the observations made with the other techniques. Moreover, the use of two new techniques in the field of saffron quality determination, i.e., SEM-EDX and ICP-OES, proved to be effective for the determination of elemental composition and metal content, which are two important parameters to take into consideration when assessing the quality of the spice.

Quantitative Leaching of Awo Mica Ore in Acetic Acid Solutions

Mica is mined and processed throughout the world and used as functional filler in many applications, such as in joint compound, electrical insulation, and plastics. The single most important feature of mica is high aspect ratio, the ratio of width to thickness. High aspect ratio mica filler is desirable in specialty applications, such as in automotive plastics, electrical industry. Considering these applications, Awo mica was quantitatively leached using acetic acid with focus on the determination of elemental composition of the ore using XRF technique, the determination of mineralogical purity of the ore using XRD, SEM and EDS techniques, the determination of the dissolution rate using acetic acid so as to predict the optimum conditions for the beneficiation of the ore for industrial applications and lastly, to investigate the potential for developing flake muscovite deposits in Southwestern Nigeria. Various parameters like effect of leachant concentration, temperature and the particle size have been investigated. Increase in leachant concentration and temperature brings about increase in dissolution rate and decrease in particle size increases the dissolution rate. The calculated reaction order and Activation energy (Ea) was 0.9437 and 21 kJ/mol respectively. The shrinking core model employed showed diffusion-controlled mechanism as the rate determining step for the dissolution process. Detailed ore characterization, for example the XRF for the elemental analysis shows that SiO2 is the most abundant compound (58.30%). It also contains other major compound like Al203 (18.70%) with the other detected compounds found to occur in minor to trace levels (&lt; 1%). The residual product was quantitatively characterized by XRD and SEM instrumentations.

Derivatization to increase the detectability of small peptides in blood serum in the analysis by ESI and MALDI high resolution mass spectrometric methods

This work highlights the efficient approach to highly sensitive determination of dipeptides that can present in biological liquids at very low and trace quantities. The approach involves preliminary derivatization of peptides with tris(2,4,6-trimethoxyphenyl)-methyl carbenium hexafluoroborate followed by ESI and MALDI high-resolution mass spectrometry. Using model dipeptides with various amino acid compositions and sequences, it was shown that the derivatization reaction proceeded smoothly in mild conditions and gave rise to pink-red colored salt derivatives. Ready cations of interest for the analysis are easily desorbed from the salt-derivatives providing strong signals in ESI and MALDI mass spectra and this ensures high sensitivity of the analysis. Another positive aspect is the removal of the target signal from the region of a matrix noise, since the introduced fragment possesses a large mass increment (359 Da). High resolution mass spectrometry, which provides the determination of accurate weights and elemental compositions of ions, was used to reliably detect model dipeptides added to artificial urine and blood serum. A number of these dipeptides was shown to be present in real blood serum collected from volunteers. Collision induced dissociation of precursor cations composed of derivatizing reagent and dipeptide moieties gives rise to characteristic and simple fragmentation mass spectra. A comparison of limits of detection (LOD) measured for non-modified and derivatized dipeptides showed that the latter derivatives provide the highest sensitivity when LOD is determined by using multiple reaction monitoring (MRM) transitions. The suggested derivatization approach was shown to be useful for unambiguous identification of special dipeptides in artificial media and dietary supplements.