Articles de revues : « Couplage ICP-MS »

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Le Bouil, Anne. « Spéciation de l'arsenic par couplage LC-ICP-MS : avantages et inconvénients en biologie médicale ». Annales de Toxicologie Analytique 19, n^o 1 (2007) : 81–86. http://dx.doi.org/10.1051/ata:2007012.

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Séby, Fabienne, Jean Dumont, Christine Gleyzes, Mathieu Menta, Véronique Vacchina et Maïté Bueno. « Analyse de formes chimiques et de nanoparticules dans les échantillons d’eau : méthodes analytiques, préconcentration et validation ». Revue des sciences de l’eau 28, n^o 1 (21 avril 2015) : 27–32. http://dx.doi.org/10.7202/1030004ar.

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Il est maintenant reconnu que la mesure de la concentration totale d’un élément ne permet pas d’obtenir d’information fiable sur son impact environnemental et sa toxicité, ces éléments pouvant être présents sous différentes formes chimiques ou à l’état de nanoparticules (NPs). Il est alors nécessaire de faire appel à des techniques de fractionnement en taille pour les NPs ou à des analyses de spéciation permettant d'identifier et doser les différentes formes chimiques des éléments. Cette approche nécessite de disposer de protocoles d’échantillonnage, de conservation et de préparation d’échantillon stricts qui ne modifient pas la répartition des formes chimiques, notamment. Étant donné les nouvelles exigences des normes, cette approche nécessite également des outils analytiques de plus en plus précis, sensibles et robustes. Le couplage de techniques séparatives basées sur la chromatographie (liquide ou gazeuse) ou le fractionnement de flux, d’une part, et la spectrométrie de masse à plasma induit (ICP MS), d’autre part, présente un réel potentiel pour ces analyses. Ces approches sont détaillées d’une manière générale en termes de potentiels et de performances analytiques et des applications sont présentées pour différents éléments (As, Hg, Sn, Cr ou Sb). Au travers de ces différents exemples, sont particulièrement abordés :

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Ye, Lambiénou, Désiré Jean Pascal Lompo, Aboubakar Sako et Hassan Bismarck Nacro. « Evaluation of trace metal content in soils subjected to inputs of solid urban wastes ». International Journal of Biological and Chemical Sciences 14, n^o 9 (25 mars 2021) : 3361–71. http://dx.doi.org/10.4314/ijbcs.v14i9.31.

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Large amounts of solid urban waste (SUW), sometimes containing trace metal (TM), are used to fertilize agricultural soils. The aim of this study was to assess concentrations of TM in peri-urban agricultural soils exposed to SUW inputs around Bobo-Dioulasso. Composite samples of fourteen soil profiles (0-20 cm, 20-40 cm and 40-60 cm) were collected in the classified Dindéréso forest in the outskirts of Bobo-Dioulasso. Inductively coupled plasma mass spectrometry (ICP/MS) was used to analyze TM concentrations in the samples. Concentrations of Cd, Cr, Cu, Ni, Pb and Zn varied broadly according to the sampling sites and soil horizons. The maximum concentrations of the analyzed elements in all sites were lower than the limit concentrations. Regardless soil horizons, the pollution index were less than 1, suggesting that the sampled soils were not subject to multiple contaminations of TM. D’importantes quantités de déchets urbains solides (DUS), renfermant parfois des éléments traces métalliques (ETM), sont utilisées pour fertiliser les sols agricoles. Le but de cette étude est d’évaluer les concentrations en ETM des sols péri-urbains de la ville de Bobo-Dioulasso soumis à l’épandage des DUS. Des échantillons composites de sols ont été prélevés, suivant les horizons 0-20 cm, 20-40 cm et 40-60 cm, sur quatorze sites dans la forêt classée de Dindérésso située à la périphérie de la ville de Bobo-Dioulasso. L’analyse des échantillons de sol a été effectuée par spectrométrie de masse avec plasma à couplage inductif (ICP/MS). Les résultats montrent que les concentrations en Cd, Cr, Cu, Ni, Pb et Zn des sols sont très variées. Elles varient en fonction de l’ETM, du site et de l’horizon du sol. Les concentrations des différents ETM dans les sols sont inférieures aux valeurs limites sur tous les sites. L’index de pollution de chaque site est inférieur à 1, quel que soit l’horizon de sol, suggérant ainsi que les sites de la zone ne font pas l’objet d’une contamination multiple de leurs sols par les ETM.

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Kagadju, Napoléon Amani, Pascal Nguo Balingene, Isaac Balume Kayani et Juste Yamonekawasso. « Impacts des décharges incontrôlées sur la qualité du sol dans les quartiers péri-urbains de la ville de Goma (Est RD Congo) : cas du quartier MUGUNGA ». International Journal of Biological and Chemical Sciences 17, n^o 4 (19 septembre 2023) : 1738–49. http://dx.doi.org/10.4314/ijbcs.v17i4.35.

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Le dépôt de déchets dans les décharges sauvages est une pratique qui ne laisse pas sain l’environnement. L’objectif de ce travail était d’évaluer les risques de contamination de l’environnement restreint en Eléments Traces Métalliques (ETM) par les décharges. Pour ce faire, deux décharges incontrôlées dont MUGUNGA I et MUGUNGA II et un site non colonisé par les déchets municipaux (témoin) ont fait l’objet des investigations. Des échantillons composites de sols ont été prélevés à la profondeur de 0-30 cm sur les trois sites. De plus, les cultures d’amarantes ont été installées et suivies sur les différents sites. Les analyses des échantillons de sol et de biomasse aérienne d’amarante ont été effectuées par spectrométrie de masse avec plasma à couplage inductif (ICP/MS). Les résultats ont montré que les concentrations en ETM (Cu, Pb, Zn, Cd et As) dans les sols étaient inférieures aux valeurs limites sur tous les sites. L’index de pollution de chaque site est inférieur à 1. Dans la biomasse aérienne d’amarante, les concentrations en Cu, Cd et As étaient inférieures à la Concentration Maximale Réglementaire (CMR) ; l’on note néanmoins des concentrations en Zn et Pb supérieures aux CMR. English title: Impacts of uncontrolled landfills to the soil quality in the peri urban areas for Goma city Mugunga district case The dumping of waste in wild dumps is a practice that does not leave the environment healthy. The objective of this work was to assess the risk of contamination of the restricted environment in metallic Trace Elements (TME) by landfills. To do this, two uncontrolled landfills including MUGUNGA I and MUGUNGA II and a site not colonized by municipal waste (control) were investigated. Composite soils samples were taken at the depth of 0-30 cm at the three sites. In addition, amaranth cultures have been installed and monitored on the various sites. In addition, amaranth cultures have been installed and monitored on the various sites. Analyzes of soils and aboveground amaranth biomass samples were performed by inductively coupled plasma mass spectrometry (ICP/MS). The result showed that the concentrations of TME (Cu, Pb, Zn and As) in the soils were below the limit values on all the sites. The pollution index for each site was less than 1. In the aerial amaranth biomass, the concentrations of Cu, Cd and As were below the Maximum Regulator Concentration (MRC); however, there were Zn and Pb concentrations above the MRC.

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Darrouzes, Jérôme. « Spectromètre de masse à plasma à couplage inductif (ICP-MS) à cellule de collision/réaction (CC/R) pour l'analyse clinique. Performances et applications à l'analyse élémentaire et à la spéciation ». Annales de Toxicologie Analytique 19, n^o 1 (2007) : 103–11. http://dx.doi.org/10.1051/ata:2007015.

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Deng, Dongyan, Shu Zhang, He Chen, Lu Yang, Hui Yin, Xiandeng Hou et Chengbin Zheng. « Online solid sampling platform using multi-wall carbon nanotube assisted matrix solid phase dispersion for mercury speciation in fish by HPLC-ICP-MS ». Journal of Analytical Atomic Spectrometry 30, n^o 4 (2015) : 882–87. http://dx.doi.org/10.1039/c4ja00436a.

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Faltusová, Veronika, Tomáš Vaculovič, Markéta Holá et Viktor Kanický. « Ilaps – python software for data reduction and imaging with LA-ICP-MS ». Journal of Analytical Atomic Spectrometry 37, n^o 4 (2022) : 733–40. http://dx.doi.org/10.1039/d1ja00383f.

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In the past couple of years, laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) has been widely used for trace element analysis in solid samples and the study of their distribution.

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Manard, Benjamin T., C. Derrick Quarles, E. Miller Wylie et Ning Xu. « Laser ablation – inductively couple plasma – mass spectrometry/laser induced break down spectroscopy : a tandem technique for uranium particle characterization ». Journal of Analytical Atomic Spectrometry 32, n^o 9 (2017) : 1680–87. http://dx.doi.org/10.1039/c7ja00102a.

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Laser ablation – inductively coupled plasma – mass spectrometry (LA-ICP-MS) in tandem with laser induced breakdown spectroscopy (LIBS) was employed to chemically map and characterize uranium particles.

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Gratuze, Bernard, Alain Giovagnoli, J. N. Barrandon, Philippe Telouk et Jean-Louis Imbert. « Apport de la méthode ICP-MS couplée à l'ablation laser pour la caractérisation des archéomatériaux ». Revue d'Archéométrie 17, n^o 1 (1993) : 89–104. http://dx.doi.org/10.3406/arsci.1993.908.

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Kataba, Andrew, Shouta M. M. Nakayama, Hokuto Nakata, Haruya Toyomaki, Yared B. Yohannes, John Yabe, Kaampwe Muzandu et al. « An Investigation of the Wild Rat Crown Incisor as an Indicator of Lead (Pb) Exposure Using Inductively Couple Plasma Mass Spectrometry (ICP-MS) and Laser Ablation ICP-MS ». International Journal of Environmental Research and Public Health 18, n^o 2 (18 janvier 2021) : 767. http://dx.doi.org/10.3390/ijerph18020767.

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Lead (Pb) is a metal toxicant of great public health concern. The present study investigated the applicability of the rat incisor in Pb exposure screening. The levels of lead in teeth (Pb-T) in the crown and root of incisors in laboratory Pb-exposed Sprague Dawley rats were quantified using inductively coupled plasma mass spectrometry (ICP-MS). The crown accumulated much Pb-T than the root of the Sprague Dawley rat incisor. The levels of lead in blood (Pb-B) were positively correlated with the Pb-T in the crown and root incisors of the Sprague Dawley rats. As an application of the Pb-T crown results in experimental rats, we subsequently analyzed the Pb-T in the crown incisors of Pb-exposed wild rats (Rattus rattus) sampled from residential sites within varying distances from an abandoned lead–zinc mine. The Pb-T accumulation in the crown of incisors of R. rattus rats decreased with increased distance away from the Pb–Zn mine. Furthermore, the Pb-T was strongly correlated (r = 0.85) with the Pb levels in the blood. Laser ablation ICP-MS Pb-T mappings revealed a homogenous distribution of Pb in the incisor with an increased intensity of Pb-T localized in the tip of the incisor crown bearing an enamel surface in both Sprague Dawley and R. rattus rats. These findings suggest that Pb-T in the crown incisor may be reflective of the rat’s environmental habitat, thus a possible indicator of Pb exposure.

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Li, Geng, et You Nan Zhu. « Spectroscopy Characterization of Multi-Treated Yellow Sapphire from Changle, China ». Materials Science Forum 833 (novembre 2015) : 90–93. http://dx.doi.org/10.4028/www.scientific.net/msf.833.90.

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Be-diffused yellow sapphires from Changle, Shandong Province, are studied by using magnification observation, ultraviolet-visible (UV-Vis) Spectroscopy, infrared (IR) Spectroscopy and Laser Ablation Inductively Couple Plasma Mass Spectrometer (LA-ICP-MS). The high content of Fe, Ti and Ga, is the typical for sapphire from basalt origin from Changle, while the Be concentrations indicate those sapphire are heated with Be Be diffused,. The IR absorption band at 3310 cm-1 of OH vibration disappears, which suggests those sapphires are heated at high temperature in a highly oxidizing atmosphere. The Fe3+ absorption bands in UV-Vis at 377, 380 and 450 nm, confirm the sapphires are heated in oxidizing atmosphere, while Fe2+-related absorption bands at 735 and 847 nm prove those yellow sapphires are from reducing atmosphere after Be-diffusion. The results of IR, UV-Vis and LA-ICP-MS indicate those yellow sapphire are originally from basalt in Changle and treated through multiple procedures, involved of Be-diffusion in highly oxidizing atmosphere and heat in reducing atmosphere. The Be-diffusion treatment diffuses beryllium into the crystal lattice in oxidizing atmosphere to lighten dark blue tones and make yellow color appear. Moreover, the sapphires undergo second heat treatment in reducing atmosphere after Be-diffusion to reduce the brown tunes of diffused sapphires.

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Moustakas, Michael, Anetta Hanć, Anelia Dobrikova, Ilektra Sperdouli, Ioannis-Dimosthenis S. Adamakis et Emilia Apostolova. « Spatial Heterogeneity of Cadmium Effects on Salvia sclarea Leaves Revealed by Chlorophyll Fluorescence Imaging Analysis and Laser Ablation Inductively Coupled Plasma Mass Spectrometry ». Materials 12, n^o 18 (12 septembre 2019) : 2953. http://dx.doi.org/10.3390/ma12182953.

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In this study, for a first time (according to our knowledge), we couple the methodologies of chlorophyll fluorescence imaging analysis (CF-IA) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), in order to investigate the effects of cadmium (Cd) accumulation on photosystem II (PSII) photochemistry. We used as plant material Salvia sclarea that grew hydroponically with or without (control) 100 μM Cd for five days. The spatial heterogeneity of a decreased effective quantum yield of electron transport (ΦPSΙΙ) that was observed after exposure to Cd was linked to the spatial pattern of high Cd accumulation. However, the high increase of non-photochemical quenching (NPQ), at the leaf part with the high Cd accumulation, resulted in the decrease of the quantum yield of non-regulated energy loss (ΦNO) even more than that of control leaves. Thus, S. sclarea leaves exposed to 100 μM Cd exhibited lower reactive oxygen species (ROS) production as singlet oxygen (1O2). In addition, the increased photoprotective heat dissipation (NPQ) in the whole leaf under Cd exposure was sufficient enough to retain the same fraction of open reaction centers (qp) with control leaves. Our results demonstrated that CF-IA and LA-ICP-MS could be successfully combined to monitor heavy metal effects and plant tolerance mechanisms.

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Hagarová, Ingrid, Lucia Nemček, Martin Šebesta, Ondřej Zvěřina, Peter Kasak et Martin Urík. « Preconcentration and Separation of Gold Nanoparticles from Environmental Waters Using Extraction Techniques Followed by Spectrometric Quantification ». International Journal of Molecular Sciences 23, n^o 19 (28 septembre 2022) : 11465. http://dx.doi.org/10.3390/ijms231911465.

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The quantification of gold nanoparticles (AuNP) in environmental samples at ultratrace concentrations can be accurately performed by sophisticated and pricey analytical methods. This paper aims to challenge the analytical potential and advantages of cheaper and equally reliable alternatives that couple the well-established extraction procedures with common spectrometric methods. We discuss several combinations of techniques that are suitable for separation/preconcentration and quantification of AuNP in complex and challenging aqueous matrices, such as tap, river, lake, brook, mineral, and sea waters, as well as wastewaters. Cloud point extraction (CPE) has been successfully combined with electrothermal atomic absorption spectrometry (ETAAS), inductively coupled plasma mass spectrometry (ICP-MS), chemiluminescence (CL), and total reflection X-ray fluorescence spectrometry (TXRF). The major advantage of this approach is the ability to quantify AuNP of different sizes and coatings in a sample with a volume in the order of milliliters. Small volumes of sample (5 mL), dispersive solvent (50 µL), and extraction agent (70 µL) were reported also for surfactant-assisted dispersive liquid–liquid microextraction (SA-DLLME) coupled with electrothermal vaporization inductively coupled plasma mass spectrometry (ETV-ICP-MS). The limits of detection (LOD) achieved using different combinations of methods as well as enrichment factors (EF) varied greatly, being 0.004–200 ng L−1 and 8–250, respectively.

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Waters, A. S., et J. G. Webster-Brown. « Assessing aluminium toxicity in streams affected by acid mine drainage ». Water Science and Technology 67, n^o 8 (1 avril 2013) : 1764–72. http://dx.doi.org/10.2166/wst.2013.051.

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Acid mine drainage (AMD) has degraded water quality and ecology in streams on the Stockton Plateau, the site of New Zealand's largest open-cast coal mining operation. This has previously been attributed largely to the effects of acidity and elevated aluminium (Al) concentrations. However, the toxicity of dissolved Al is dependent on speciation, which is influenced by pH which affects Al hydrolysis, as well as the concentrations of organic carbon and sulphate which complex Al. Methods for the assessment of the toxic fraction of Al, by chemical analysis and geochemical modelling, have been investigated in selected streams on the Stockton Plateau, where dissolved Al concentrations ranged from 0.034 to 27 mg L−1. Modelling using PHREEQC indicated that between 0.2 and 85% of the dissolved Al was present as the free ion Al3+, the most toxic Al species, which dominated in waters of pH = 3.8–4.8. Al-sulphate complexation reduced the Al3+ concentration at lower pH, while Al-organic and –hydroxide complexes dominated at higher pH. Macroinvertebrate richness in the streams identified an Al3+ ‘threshold’ of approximately 0.42 mg/L, above which taxa declined rapidly. Colorimetric ‘Aluminon’ analysis on unpreserved, unfiltered waters provided a better estimation of Al3+ concentrations than inductively couple plasma–mass spectrometry (ICP-MS) on filtered, acidified waters. The Aluminon method does not react with particulate Al or strong Al complexes, often registering as little as 53% of the dissolved Al concentration determined by ICP-MS.

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Yuningsih, Euis Tintin. « HOST ROCK AND MINERALIZED ORES GEOCHEMISTRY OF BANTARHUNI VEIN, ARINEM DEPOSIT, WEST JAVA – INDONESIA ». Bulletin of Scientific Contribution 14, n^o 3 (26 janvier 2017) : 223. http://dx.doi.org/10.24198/bsc.vol14.yr2016.art10964.

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There are closed spatial relationship between the different phases, the different metallic minerals, the precious-metals bearing minerals, the volcanic host rock and the plutonic intrusions of the Arinem vein system. Nine samples from Bantarhuni vein including four samples from quartz-sulfide vein from different stages and level, and five samples from altered host rock were analyzed geochemically by Induced Couple Plasma (ICP) and Induced Couple Plasma Mass Spectrometer (ICP-MS) to identified the geochemical characteristics of Bantarhuni vein system. The geochemical data obtained from the quartz-sulfide vein and altered host rock of the Bantarhuni vein is mostly similar to those obtained from Arinem vein samples. Some samples from the alteration zone have contents similar to the less altered Jampang Formation and andesitic Miocene and Pliocene intrusions rocks, with a little depletion and enrichment for some oxides. The abundance of ore and gangue minerals vary among each stage of mineralization of Bantarhuni vein. The REE in the Arinem and Bantarhuni veins considered to have been extracted by water/rock interaction between hydrothermal solution and country rocks. Some REE pattern of the mineralized Bantarhuni vein show irregularly pattern and this is could be due to high content of sulfide minerals in the samples, or due to analytical error during sample dissolution. The gold and silver contents in the Arinem and Bantarhuni veins vary very much and there is relatively low Au and Ag concentrations occur in samples from any alteration zone. There is no correlation found between gold and other major ore elements except for Ag. The highest content of Au is having low ΣREE. Keywords : Bantarhuni vein, Geochemical, quartz-sulfide vein, water-rock interaction. Terdapat hubungan spasial antara fase yang berbeda, mineral logam yang berbeda, mineral yang mengandung logam mulia, batuan induk (host rock) vulkanik dan intrusi plutonik dalam sistem urat Arinem. Sembilan sampel dari urat Bantarhuni yang terdiri dari empat sampel dari urat kuarsa-sulfida dari stages dan kedalaman yang berbeda, dan lima sampel dari host rock yang terubah dianalisis secara geokimia degan Induced Couple Plasma (ICP) dan Induced Couple Plasma Mass Spectrometer (ICP-MS) untuk mengidentifikasi karakteristik geokimia dari sistem urat Bantarhuni. Data analisis geokimia yang diperoleh dari urat kuarsa-sulfida dan batuan induk terubah dari urat Bantarhuni sebagian besar sama dengan yang diperoleh dari sampel urat Arinem. Beberapa sampel dari zona alterasi memiliki kandungan mirip dengan Formasi Jampang yang terubah lemah dan batuan intrusi andesit berumur Miosen dan Pliosen, dicirikan dengan sedikit pengurangan dan pengayaan untuk beberapa oksida. Kelimpahan bijih dan mineral gang bervariasi di dalam setiap tahap mineralisasi di urat Bantarhuni. REE di urat Arinem dan Bantarhuni kemungkinan diekstraksi dengan adanya interaksi air/batuan antara fluida hidrothermal dan batuan sampingnya. Beberapa pola REE dari urat Bantarhuni yang termineralisasi menunjukkan pola yang tidak teratur dan hal ini kemungkinan disebabkan oleh tingginya kandungan mineral sulfida dalam sampel, atau karena kesalahan pada saat analisis dalam pelarutan sampel. Kandungan emas dan perak dalam urat Arinem dan Bantarhuni sangat bervariasi dan konsentrasi Au dan Ag pada sampel dari setiap zona alterasi relatif rendah. Tidak ada korelasi ditemukan antara emas dan unsur bijih utama lainnya kecuali dengan Ag. Sampel dengan kandungan Au tertinggi adalah sampel yang memiliki ΣREE rendah. Kata kunci: Urat Bantarhuni, geokimia, urat kuarsa-sulfida, interaksi air-batuan.

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El Afia, Zobair, Mohamed Youssef Messous, Mohamed Cherkaoui et Mounia Tahri. « Synthesis, Structural and Optical Characterization of Titanium Dioxide Doped by (Ce, Yb) Dedicated to Photonic Conversion ». Indonesian Journal of Chemistry 20, n^o 1 (31 décembre 2019) : 175. http://dx.doi.org/10.22146/ijc.43947.

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The synthesis of TiO2 co-doped by (Ce, Yb) rare earth couple has been realized. This couple of rare earth can convert a high-energy photon to two low energy photons to enhance the energy efficiency of silicon solar cells. The undoped, 2% Ce doped- and (2% Ce, 4% Yb) Codoped- Titanium oxide were prepared by the co-precipitation method. The Infrared spectroscopy FTIR-ATR analysis indicates a continuous visible absorption in the 750–400 cm–1 region, confirming the formation of a titanium-oxygen bond. The X-Ray Diffraction characterization showed the dominance of the rutile crystalline phase with the presence of anatase one and the calculated crystallite size is between 7 to 13 nm. The X-Ray Fluorescence confirms the insertion of the dopants while the Inductively Coupled Plasma Mass Spectrometry ICP-MS showed the ratio 2 between Ce and Yb concentration. The thermogravimetric analysis indicated that Ce/Yb doped titanium was thermally stable. The absorption in the UV-visible (200 and 1000 nm) has been improved proportionally with the dopants.

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Pring, Allan, Benjamin Wade, Aoife McFadden, Claire E. Lenehan et Nigel J. Cook. « Coupled Substitutions of Minor and Trace Elements in Co-Existing Sphalerite and Wurtzite ». Minerals 10, n^o 2 (9 février 2020) : 147. http://dx.doi.org/10.3390/min10020147.

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The nature of couple substitutions of minor and trace element chemistry of expitaxial intergrowths of wurtzite and sphalerite are reported. EPMA and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analyses display significant differences in the bulk chemistries of the two epitaxial intergrowth samples studied. The sample from the Animas-Chocaya Mine complex of Bolivia is Fe-rich with mean Fe levels of 4.8 wt% for wurztite-2H and 2.3 wt% for the sphalerite component, while the sample from Merelani Hills, Tanzania, is Mn-rich with mean Mn levels in wurztite-4H of 9.1 wt% and for the sphalerite component 7.9 wt% In both samples studied the wurtzite polytype is dominant over sphalerite. LA-ICP-MS line scans across the boundaries between the wurtzite and sphalerite domains within the two samples show significant variation in the trace element chemistries both between and within the two coexisting polytypes. In the Merelani Hills sample the Cu+ + Ga3+ = 2Zn2+ substitution holds across both the wurztite and sphalerite zones, but its levels range from around 1200 ppm of each of Cu and Ga to above 2000 ppm in the sphalerite region. The 2Ag+ + Sn4+ = 3Zn2+ coupled substitution does not occur in the material. In the Animas sample, the Cu+ + Ga3+ = 2Zn2+ substitution does not occur, but the 2(Ag,Cu)+ + Sn4+ = 3Zn2+ substitution holds across the sample despite the obvious growth zoning, although there is considerable variation in the Ag/Cu ratio, with Ag dominant over Cu at the base of the sample and Cu dominant at the top. The levels of 2(Ag,Cu)+ + Sn4+ = 3Zn2+ vary greatly across the sample from around 200 ppm to 8000 ppm Sn, but the higher values occur in the sphalerite bands.

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., Manisha, Anima Sunil Dadhich et Anik Sen. « Preparation of barium ferrate from mill scale and degradation study of aqueous Eriochrome black – T ». Research Journal of Chemistry and Environment 27, n^o 2 (15 janvier 2023) : 10–19. http://dx.doi.org/10.25303/2702rjce10019.

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This present study involves the utilization of mill scale, an iron rich steel industry waste, to synthesize barium ferrate. Ferrate with iron in +(VI) oxidation state is a green chemical with promising oxidation, disinfection and coagulation properties. The X-Ray diffraction(XRD) analysis of mill scale indicates the presence of iron in three forms hematite, magnetite and wustite. Mill scale was dissolved in concentrated HCl. The metallic composition of dissolved mill scale was determined by Inductively Couple Plasma Mass Spectroscopy(ICP-MS). Barium ferrate was synthesized using the dissolved mill scale by the wet oxidation method. The resulting crude ferrate was washed with different organic solvents to remove the impurities. The product thus obtained was analyzed by chromite method and characterized by Fourier Transform Infrared Spectroscopy(FTIR). Degradation of aqueous Eriochrome Black – T(EBT) with barium ferrate was studied at different pH, time and concentration. The degradation of the dye was monitored by UV-Visible spectroscopy and chemical oxygen demand. The degradation products of the aqueous EBT were characterized by Gas Chromatography-Mass Spectroscopy(GC-MS) and Proton Nuclear Magnetic Resonance (1H-NMR). Computational studies were performed to compare the stability of barium ferrate with that of potassium ferrate. The 1H-NMR calculations were performed to compare the degradation products obtained experimentally.

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Bidin, Noriah B. « Detection of Pb in Whitening Creams via Laser Induced Breakdown Spectroscopy ». JOURNAL OF ADVANCES IN PHYSICS 3, n^o 1 (30 avril 2007) : 170–75. http://dx.doi.org/10.24297/jap.v3i1.2086.

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Recently whitening creams have been widely used to protect UV light exposure due to the depletion of ozone layer. The demand attracts the rapid growth of various whitening creams in the market. The detection is required in order to determine the constituent of the whitening cream, whether it contains dangerous element like heavy metal (Pb, Hg or Cr). In this attempt, laser induced breakdown spectroscopy (LIBS) technique was deployed to analyse the existence of heavy metal. Several whitening creams available in retail shop and open market were investigated. Cryogenically frozen technique was utilized to convert the emulsion into solid form. Lead Pb was detected in all the tested samples in the range of 2 - 5 ppm. The LIBS results were validated by Inductive Couple Plasma Mass Spectroscopy (ICP-MS) technique. The high sensitivity, portable and in-situ LIBS system allow simple, faster and easy heavy metal detection. This enhances the procedure of inspection in cosmetic industries

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Bühn, Bernhard, Márcio M. Pimentel, Massimo Matteini et Elton L. Dantas. « High spatial resolution analysis of Pb and U isotopes for geochronology by laser ablation multi-collector inductively coupled plasma mass spectrometry (LA-MC-ICP-MS) ». Anais da Academia Brasileira de Ciências 81, n^o 1 (mars 2009) : 99–114. http://dx.doi.org/10.1590/s0001-37652009000100011.

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Age determinations using the 235U and 238U radioactive decay series to the daughter isotopes 207Pb and 206Pb, respectively, using the mineral zircon (ZrSiO4), are widely used to decipher geological processes. A new method developed in the last couple of years, the laser ablation multi-collector inductively coupled plasma mass spectrometry (LA-MC-ICP-MS), overcomes previous laborious sample preparation, and yields isotopic ratios and age data with a high spatial resolution of ten of microns. The present study describes the analytical set-up and data reduction process as presently applied at the Laboratory for Geochronology of the University of Brasília. It explores the precision and accuracy of the method by cross-analysing three international zircon standards. We arrive at a precision of 1.9 to 3.7% (2σ SD) and an accuracy of 0.6 to 3.8% (2σ SD) for and U isotopic ratios of the standards. We also apply the method to two natural zircon samples, which have previously been dated by other analytical methods. A comparison of the results show a good conformity of the age data,being whitin the error limits. The data demonstrate the great analytical potential of the method for rapid, precise and accurate U-Pb isotopic analyses on the micron scale.

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Putiš, Marián, Yue-Heng Yang, Tomáš Vaculovič, Matúš Koppa, Xian-Hua Li et Pavel Uher. « Perovskite, reaction product of a harzburgite with Jurassic– Cretaceous accretionary wedge fluids (Western Carpathians, Slovakia) : evidence from the whole-rock and mineral trace element data ». Geologica Carpathica 67, n^o 2 (1 avril 2016) : 135–48. http://dx.doi.org/10.1515/geoca-2016-0009.

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Abstract Perovskite (Prv) was discovered in an abyssal harzburgite from a “mélange” type blueschist-bearing accretionary wedge of the Western Carpathians (Meliata Unit, Slovakia). Perovskite-1 formation in serpentinized orthopyroxene may be simplified by the mass-balance reaction: Ca2Si2O6 (Ca-pyroxene-member)+2Fe2TiO4 (ulvöspinel molecule in spinel)+2H2O+O2=2CaTiO3 (Prv)+2SiO2+4FeOOH (goethite). Perovskite-2 occurs in a chlorite-rich blackwall zone separating serpentinite and rodingite veins, and in rodingite veins alone. The bulk-rock trace-element patterns suggest negligible differences from visually and microscopically less (“core”) to strongly serpentinized harzburgite due to serpentinization and rodingitization: an enrichment in LREE(La,Ce), Cs, ±Ba, U, Nb, Pb, As, Sb, ±Nd and Li in comparison with HREE, Rb and Sr. The U/Pb perovskite ages at ~135 Ma are interpreted to record the interaction of metamorphic fluids with harzburgite blocks in the Neotethyan Meliatic accretionary wedge. Our LA-ICP-MS mineral study provides a complex view on trace element behaviour during the two stages of rodingitization connected with Prv genesis. The positive anomalies of Cs, U, Ta, Pb, As, Sb, Pr and Nd in Cpx, Opx and Ol are combined with the negative anomalies of Rb, Ba, Th, Nb and Sr in these minerals. The similar positive anomalies of Cs, U, Ta, ±Be, As, Sb found in typical serpentinization and rodingitization minerals, with variable contents of La, Ce and Nd, and negative anomalies of Rb, Ba, Th, Nb and Sr suggest involvement of crustal fluids during MP-LP/LT accretionary wedge metamorphism. LA-ICP-MS study revealed strong depletion in LREE from Prv-1 to Prv-2, and a typically negative Eu (and Ti) anomaly for Prv-1, while a positive Eu (and Ti) anomaly for Prv-2. Our multi-element diagram depicts enrichment in U, Nb, La, Ce, As, Sb, Pr, Nd and decreased Rb, Ba, Th, Ta, Pb, Sr, Zr in both Prv generations. In general, both Prv generations are very close to the end-member composition. In spite of low concentrations of isomorphic constituents, Prv-1 and Prv-2 display the A(La,Ce)3++B(Fe,Cr)3+=ACa2++BTi4+ heterovalent couple substitution. A decrease of ferric iron in Prv-2 indicates increasing reduction conditions during rodingitization.

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Folarin, Oluwabusuyi Rachael, Funmilayo E. Olopade et James Olukayode Olopade. « Essential Metals in the Brain and the Application of Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry for their Detection ». Nigerian Journal of Physiological Sciences 36, n^o 2 (31 décembre 2021) : 123–47. http://dx.doi.org/10.54548/nigerjphysiolsci.v36i2.1.

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Metals are natural component of the ecosystem present throughout the layers of atmosphere; their abundant expression in the brain indicates their importance in the central nervous system (CNS). Within the brain tissue, their distribution is highly compartmentalized, the pattern of which is determined by their primary roles. Bio-imaging of the brain to reveal spatial distribution of metals within specific regions has provided a unique understanding of brain biochemistry and architecture, linking both the structures and the functions through several metal mediated activities. Bioavailability of essential trace metal is needed for normal brain function. However, disrupted metal homeostasis can influence several biochemical pathways in different fields of metabolism and cause characteristic neurological disorders with a typical disease process usually linked with aberrant metal accumulations. In this review we give a brief overview of roles of key essential metals (Iron, Copper and Zinc) including their molecular mechanisms and bio-distribution in the brain as well as their possible involvement in the pathogenesis of related neurodegenerative diseases. In addition, we also reviewed recent applications of Laser Ablation Inductively Couple Plasma Mass Spectrophotometry (LA-ICP-MS) in the detection of both toxic and essential metal dyshomeostasis in neuroscience research and other related brain diseases

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Folarin, Oluwabusuyi Rachael, Funmilayo E. Olopade et James Olukayode Olopade. « Essential Metals in the Brain and the Application of Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry for their Detection ». Nigerian Journal of Physiological Sciences 36, n^o 2 (31 décembre 2021) : 123–47. http://dx.doi.org/10.54548/njps.v36i2.1.

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Metals are natural component of the ecosystem present throughout the layers of atmosphere; their abundant expression in the brain indicates their importance in the central nervous system (CNS). Within the brain tissue, their distribution is highly compartmentalized, the pattern of which is determined by their primary roles. Bio-imaging of the brain to reveal spatial distribution of metals within specific regions has provided a unique understanding of brain biochemistry and architecture, linking both the structures and the functions through several metal mediated activities. Bioavailability of essential trace metal is needed for normal brain function. However, disrupted metal homeostasis can influence several biochemical pathways in different fields of metabolism and cause characteristic neurological disorders with a typical disease process usually linked with aberrant metal accumulations. In this review we give a brief overview of roles of key essential metals (Iron, Copper and Zinc) including their molecular mechanisms and bio-distribution in the brain as well as their possible involvement in the pathogenesis of related neurodegenerative diseases. In addition, we also reviewed recent applications of Laser Ablation Inductively Couple Plasma Mass Spectrophotometry (LA-ICP-MS) in the detection of both toxic and essential metal dyshomeostasis in neuroscience research and other related brain diseases

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Silalahi, Evi Mardiastuty, et Endang Purwanti. « ANALISIS KANDUNGAN LOGAM BERAT TIMBAL (Pb) PADA PRODUK OLAHAN SUSU ». Food Scientia : Journal of Food Science and Technology 1, n^o 1 (9 juin 2021) : 1–10. http://dx.doi.org/10.33830/fsj.v1i1.1455.2021.

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Timbal (Pb) adalah bahan toksik yang mudah terakumulasi dalam organ manusia dan dapat mengakibatkan gangguan kesehatan berupa anemia, gangguan fungsi ginjal, gangguan sistem syaraf, otak, dan kulit. Analisis kandungan logam berat Pb pada produk olahan susu diperlukan untuk mengetahui kelayakan konsumsi produk tersebut. Penelitian ini dilakukan pada bulan Juni-Agustus 2020 di Laboratorium. Tujuan penelitian ini untuk mengetahui kadar kontaminan logam berat Pb pada produk olahan susu yang berupa susu pasteurisasi, keju, mentega, dan yoghurt dengan metode Inductively Couple Plasma-Mass Spectrometry (ICP-MS). Preparasi sampel menggunakan metode destruksi basah dengan pelarut HNO3 65% ultrapur, H2O2 30% ultrapur dan HCl ultrapur. Kadar logam berat Pb yang diperoleh dari hasil penelitian yaitu produksi pertama pada sampel susu pasteurisasi < 0,001 mg/kg, keju < 0,001 mg/kg, mentega 0,004 mg/kg, yoghurt < 0,001 mg/kg, produksi kedua pada sampel susu pasteurisasi sebesar 0,020 mg/kg, keju 0,011 mg/kg, mentega 0,006 mg/kg, yoghurt 0,025 mg/kg, dan produksi ketiga pada sampel susu pasteurisasi < 0,001 mg/kg, keju 0,008 mg/kg, mentega < 0,001 mg/kg, yoghurt < 0,001 mg/kg. Hasil penelitian tersebut dibandingkan dengan Batas Maksimum Cemaran Logam Berat dalam Pangan menurut SNI 7387:2009 dan Peraturan BPOM No 23 Tahun 2017.

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Sheppard, Paul R., et Mark L. Witten. « Dendrochemistry in Public Health : A Case Study in North Carolina, USA ». Forests 13, n^o 11 (27 octobre 2022) : 1767. http://dx.doi.org/10.3390/f13111767.

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Dendrochemistry, the measurement of element concentrations in tree rings for the purpose of assessing temporal changes in chemical environments, was used to study an area in south-central North Carolina, USA, that has experienced higher than expected incidences of a couple human illnesses. A principal objective of applying dendrochemistry around an area with public health problems is to assess the environmental chemistry through time to see if the environmental abundance of any elements has changed recently, which then might inform further research into the possible linkage between those elements and the reported illnesses. Loblolly pine is common in the study area and, therefore, was chosen for sampling. Using acid digestion ICP-MS, decadal chunks of rings were measured for the concentration of multiple elements. Most of the elements measured do not show any particular changes in concentration throughout the time period covered by the trees, but four elements (molybdenum, chromium, iron, and, possibly, vanadium) show concentrations in the most recent decade (the 2010s) that were higher than for previous decades. Because this study was ecologic in design, it is not possible to associate these elements with the illnesses that are being reported for the area based on this study alone, but further environmental monitoring might be merited to confirm the temporal pattern found here.

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Nagar, B. K., M. K. Saxena et B. S. Tomar. « Quantification of Trace and Ultra-trace Impurities in U-Zr Alloy by Inductively Couple Plasma Time of Flight Mass Spectrometry (ICP-TOF-MS) After Simultaneous Separation of U and Zr ». Atomic Spectroscopy 39, n^o 5 (25 octobre 2018) : 185–92. http://dx.doi.org/10.46770/as.2018.05.002.

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Rosita, Widya, Dea Anisa Ayu Besari, I. Made Bendiyasa, Indra Perdana, Ferian Anggara et Himawan Tri Bayu Murti Petrus. « Potency of Rare Earth Elements and Yttrium in Indonesia Coal Ash ». Key Engineering Materials 849 (juin 2020) : 102–7. http://dx.doi.org/10.4028/www.scientific.net/kem.849.102.

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Indonesia coal ash is predicted to reach 10.8 million tons in the year 2020 but its utilization is still limited. In the last decade, coal ash has become a promising REY source candidate. To determine the potency of REY in Indonesia coal ash, information about element concentration and mineralogy of the ash is essential. In this study, coal ash samples were taken from Paiton-2, Pacitan, Rembang, and Tanjung Jati coal-fired power plants. Element content and mineralogy were analyzed using Inductive Couple Plasma Mass Spectroscopy/Atomic Emission Spectroscopy (ICP-MS/AES), X-Ray Diffractometer (XRD) and petrographic. The results showed that coal fly ash and bottom ash contains critical REY in the range of 38% to 41% with Coutlook larger than one. XRD analysis showed that both fly ash and bottom ash have similar mineral phases with slightly different concentrations. The mineral phase is dominated by amorphous glass, quartz, Fe-bearing minerals, and unburned carbon. The amorphous glass phase in fly ash is in the range of 23 to 34% while in bottom ash between 14 and 34%. Unburned carbon content in fly ash and bottom ashes are 7-13% and 7-19%, respectively. Fe-bearing mineral content in fly ash is 15-20% and bottom ash is 13-20%. In addition, Indonesia coal ash has a higher Heavy-REY enrichment factor than Light-REY. The Enrichment Factor of HREY in fly ash is as much as 1.3 times (in average) of the bottom ash.

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Astuti, Widi, Agus Haerudin, Istihanah Nurul Eskani, Fajar Nurjaman, Aulia Pertiwi Tri Yuda, Joni Setiawan, Isnaeni, Farida et Dwi Wiji Lestari. « Zinc Oxide Recovery from Solid Waste of Electric Arc Furnace Dust (EAFD) Using Hydrometallurgical Method ». Key Engineering Materials 849 (juin 2020) : 108–12. http://dx.doi.org/10.4028/www.scientific.net/kem.849.108.

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Indonesia coal ash is predicted to reach 10.8 million tons in the year 2020 but its utilization is still limited. In the last decade, coal ash has become a promising REY source candidate. To determine the potency of REY in Indonesia coal ash, information about element concentration and mineralogy of the ash is essential. In this study, coal ash samples were taken from Paiton-2, Pacitan, Rembang, and Tanjung Jati coal-fired power plants. Element content and mineralogy were analyzed using Inductive Couple Plasma Mass Spectroscopy/Atomic Emission Spectroscopy (ICP-MS/AES), X-Ray Diffractometer (XRD) and petrographic. The results showed that coal fly ash and bottom ash contains critical REY in the range of 38% to 41% with Coutlook larger than one. XRD analysis showed that both fly ash and bottom ash have similar mineral phases with slightly different concentrations. The mineral phase is dominated by amorphous glass, quartz, Fe-bearing minerals, and unburned carbon. The amorphous glass phase in fly ash is in the range of 23 to 34% while in bottom ash between 14 and 34%. Unburned carbon content in fly ash and bottom ashes are 7-13% and 7-19%, respectively. Fe-bearing mineral content in fly ash is 15-20% and bottom ash is 13-20%. In addition, Indonesia coal ash has a higher Heavy-REY enrichment factor than Light-REY. The Enrichment Factor of HREY in fly ash is as much as 1.3 times (in average) of the bottom ash.

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González-Fernández, Macarena, Tamara García-Barrera, Juan Jurado, María J. Prieto-Álamo, Carmen Pueyo, Juan López-Barea et José Luis Gómez-Ariza. « Integrated application of transcriptomics, proteomics, and metallomics in environmental studies ». Pure and Applied Chemistry 80, n^o 12 (1 janvier 2008) : 2609–26. http://dx.doi.org/10.1351/pac200880122609.

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Here we report a preliminary working scheme for the integrative application of transcriptomic, proteomic, and metallomic methodologies in environmental monitoring, by using as sentinel the wildlife species Mus spretus and as reference the gene/protein sequence databases from the key model species Mus musculus. We have demonstrated that the absolute transcript expression signatures quantified by reverse transcription (RT) and real-time polymerase chain reaction (PCR) of selected key genes (e.g., those coding for biotransformation enzymes) in M. spretus is a useful and reliable novel biomonitoring end-point. The suitability of commercial M. musculus oligonucleotide arrays for genome-wide transcriptional profiling in M. spretus has been also shown. Transcriptomic studies indicate considerable gene sequence similarities between both mouse species. Based on these similarities, we have demonstrated the applicability in free-living M. spretus of high-throughput proteomic methods, based on matrix-assisted laser desorption/ionization with time-of-flight mass spectrometry (MALDI-TOFMS) analysis of tryptic 2D electrophoresis (2-DE) spot digest and peptide matching with M. musculus database. A metallomic approach based on size exclusion chromatography inductively coupled plasma-mass spectrometry (SEC-ICP-MS) was applied to trace metal-biomolecule profiles. A preliminary integration of these three -omics has been addressed to M. musculus/M. spretus couple, two rodent species that separated 3 million years ago. The integrated application of transcriptomic and proteomic data and the bidirectional use of metallomics and proteomics for selective isolation of metal-biomolecules are covered in the working scheme MEPROTRANS-triple-OMIC reported in this study.

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Mohammed, Bushra Abdullah. « The effect of grain size on the distribution and fractionation of the major chemical trace and rare earth elements in shale, silt and sand rocks of the Muqdadia formation in north of Iraq ». IOP Conference Series : Earth and Environmental Science 1300, n^o 1 (1 février 2024) : 012017. http://dx.doi.org/10.1088/1755-1315/1300/1/012017.

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Abstract (17) samples were collected from Muqdadia formation from various areas in Erbil governorate and Aqra district north of Iraq, which were represented by the sections (A, B, D, R, W). (10) samples were used in analyzing the element using Plasma–Mass Spectrometry (ICP–MS) Analysis and the Inductive Couple Plasma–Mass Spectrometry (ICP–MS) Analysis for four granule sizes after these granules were separated from each sample. The elements included were Al, Fe, Mg, Ca, Na, K, Ti, P, Rb, Cs, Sr, Ba, Au, Mo, Pb, Cu, Zn, As, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Cr, Ni, Co, Mn, Sc, V, Zr, Hf, Ta, Nb, Th, U, Ga, La, Dy, Ho, Er, Tm, Yb, Lu, Y. The geochemical study revealed that there is no significant variation in the content of the main, trace and rare earth elements in the four sizes of shale, silt, fine sand and coarse sand. Also, it was found that the sizes of silt and fine sand contain the highest portion of the trace elements and the rare earth element. It was also, noticed that the patterns of the rare earth elements in the granule sizes are similar in general with some differences, as these differences were reflected in some changes in the portions of these elements. In general, it was observed that the total content of the rare earth elements in the various sizes is relatively small and this might be due to two main factors; the high decrease by calcite (calcium carbonate) and the free silica (quartz) and the other reason is that the mineral that contain REEs are mostly derived from rock sources (mafic or ultra-mafic), which contain these elements with low concentrations. Patterns of REE in the study samples and the four sizes are similar to the pattern of (PAAS) with slight differences like the presence of LREE and on a lower level in HREE and also the presence of negative anomaly Ce*/Ce in the size of shale, silt, fine sand and coarse sand. Although there are variations in the values of anomaly Eu* /Eu, the values are not far from the acceptable PAAS values and they are, generally, higher than PAAS due to the presence of the mafic and ultra-mafic component in the sediments of the current study. In all the sizes, except the shale size, it was found that ∑ REE varies and increases with the increase of the contents of Al2O3 and Fe2O3. As for the shale size, it was found that the relationship between REE∑, Mn and P2O5 is negative and this is because the shale were sedimented in river environments that don’t permit them to absorb sufficient amounts of REE as is the case with the shale that are sedimented in sea environments where there is a direct contact with the seawater that although contains slight concentrations of REE but they are effective when they are adsorbed on shale particularly when the average sedimentation of the shale is low. But in the current study, the shale is river sediments and the river contains insignificant concentrations of REE and the sediment in the river is faster compared to the sea environment and this case doesn’t permit the shale to adsorb large portions of REE.

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Amiewalan, Florence O., Frankie O. Balogun et Kingsley Ejairu. « Sedimentological and geochemical characterization of DF-2 well, Onshore Western Niger Delta : Implications for provenance, tectonic history and paleo depositional conditions ». Global Journal of Pure and Applied Sciences 26, n^o 2 (2 novembre 2020) : 141–55. http://dx.doi.org/10.4314/gjpas.v26i2.6.

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The sedimentology and geochemistry of the major oxides and trace elements of DF-2 well, Onshore, Niger Delta, are presented in this study. The study is aimed at describing the sedimentological characteristics as well as using the major oxides and trace elements to investigate the provenance, tectonic history and palaeo-depositional conditions of the well. Selected samples were investigated with fused bead X-Ray Fluorescence (XRF) spectrometry to determine their major oxides and fused bead laser ablation inductively couple plasma mass spectroscopy (LA-ICP-MS) for their trace elements. Sedimentological analysis from the well shows that the lithology ranged from shaly sand, sandy shale, sandstone and shale. The results show the dominance of silicon oxide (SiO2) contents which ranges from 81.1 to 91.4 wt. % (average of 87.1 wt. %). The low average concentration of Cr<150 ppm and Ni <100 ppm, the ratios of Th/Sc, Th/Co, Th/Cr, Cr/Th, La/Sc, as well as the plots of Th/Co versus La/Sc and TiO2 versus Zr, all infer a felsic source rock. The discrimination plots of ratioK2O/Na2O against SiO2 and Log K2O/Na2O against Log SiO2/Al2O3 indicated passive continental margin. Various chemical classifications of the sediments show that the sandstone facies plotted mainly in quartzarenite, sublitharenite and Fe-rich sand domains. The samples were deposited under oxic environment based on the average values of U/Th (0.26 ppm), Ni/Co (2.79 ppm) and Cu/Zn (1.81ppm) and bivariate plot of Ni/Co versus V/Cr. However, the bivariate plot of Ni/Co versus V/ (V+Ni) specifies oxic to anoxic conditions and V/Vi + Ni ratios indicate oxic, suboxic to euxinicpalaeode positional environments for the sediments. Geochemical characterization illustrates mixed marine and terrigenous source input, deposited mainly in semi humid/humid climate. The positive values attained from ratios of Al2O3/(CaO+MgO+Na2O+K2O) infers mineralogical maturity based on stable mobile oxides content in the studied samples. Keywords: Felsic Rock, Quartzarenite, Litharenite, Passive Margin, Mobile Oxide, Mature Sediments.

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AJIBADE, OLUMUYIWA MICHAEL, SEUN DAMOLA OLADIPUPO, TEMITOPE MONSURAT OSOBAMIRO et BANKOLE JULIUS KAYODE. « GEOPHAGIC CLAY PREDOMINANCE AND ITS POSSIBLE HEALTH IMPLICATIONS IN THE SOUTH-EAST REGION OF NIGERIA ». JOURNAL OF SUSTAINABILITY SCIENCE AND MANAGEMENT 17, n^o 8 (31 août 2022) : 97–117. http://dx.doi.org/10.46754/jssm.2022.08.006.

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Geophagy has been a common practice especially in the Southern part of Nigeria and some parts of the world at large. They are earthy/clay materials eaten as food supplements and also adopted for medical purposes. Hence, they are bound to contain trace metal contents that may be harmful to human health which is a great cause for concern among health workers in this modern age. Therefore, geophagic clays from Amawom- Ikwanoin Abia province, South-eastern Nigeria were examined and evaluated for their heavy metal concentration to deduce their quality and possible health implication that is associated with their consumption. Edible clay from south eastern Nigeria was analysed with X-ray Diffraction (XRD), Scanning Electron Microscope (SEM) and Inductively Couple Plasma Mass-Spectrometry (ICP-MS) revealing quartz (SiO2), kaolinite (Al2Si2O5(OH)4, goethite (FeOH) and pyrite (FeS2) as the predominant minerals while SEM revealed clay flaky structure specifying an alumino-silicate with sulfur and carbon as impurities. The clay’s pH ranges between 3.36 and 4.57, E.C from 52-399 μs/cm revealed its high acidity and signified high ionic contents in the edible clays. The soil Organic Carbon 0.1-5.83% may possibly indicate absorption and retention of contaminants. High concentrations ppm for Cu(19.91), Pb(13.15), Zn(18.4), Ni(5.8), As(9.15) and Hg(126.0) in the clay exceeded the WHO and USEPA recommended dietary intake by humans signifying its likely toxicity. Other associated carcinogenic and non-carcinogenic diseases that could be connected to the high concentrations of mercury, chromium, arsenic, lead and nickel in the edible clay structure which may likely camouflage the taunt and healing properties of kaolinite include renal, respiratory, cardiovascular, gastrointestinal, hepatic, immune, reproductive and dermal systems. For this reason, continuous ingestion of edible clay may lead to bio-accumulation of mercury, chromium, arsenic, lead and nickel in the inhabitants of Amawom, hence, posing serious health challenges that may lead to death.

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Montiel, A., et B. Welté. « Les progrès dans la mise en évidence d'éléments traces dans les eaux - avenir des techniques ». Revue des sciences de l'eau 11 (12 avril 2005) : 119–28. http://dx.doi.org/10.7202/705334ar.

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L'évolution des techniques analytiques est, la plupart du temps, liée à l'apparition de nouvelles normes concernant l'environnement ou l'eau potable. En ce qui concerne les micropolluants minéraux, si dans le passé une attention toute particulière avait été apportée à la connaissance des formes sous lesquelles ils étaient dans les eaux, toutes les normes proposées depuis n'ont pas repris cette approche, et toutes concernent l'élément total non différencié. Les méthodes de spéciation ne seraient donc plus à l'ordre du jour. Il n'en est rien, car les limites fixées étant de plus en plus basses, la connaissance des formes, des valences sous lesquelles se trouvent ces éléments est de plus en plus importante pour l'optimisation des traitements curatifs. C'est le cas par exemple, du fer, de l'arsenic, du sélénium et du chrome. L'arsenic, par exemple, ne peut être éliminé de façon convenable, que s'il se trouve à la valence V. Une oxydation préalable peut donc être nécessaire. Pour le chrome, c'est le contraire, à la valence VI, cet élément n'est pas éliminable, il faut donc le réduire pour le faire passer à la valence III. Une autre évolution de l'analyse concerne les possibilités offertes par les couplages ICP-MS. En effet, la connaissance pour un élément des rapports isotopiques peut être primordial pour retrouver l'origine d'une pollution. Deux cas sont présentés : 1. Un élément lourd, qui ne connaît pas ou très peu de ségrégations isotopiques, c'est le cas du plomb. - Lors d'enquête sur la plombémie des enfants, il peut être mis en évidence des plombémies importantes (> 150 µg/l de sang). L'origine de ce plomb pouvant être multiple : pollution atmosphérique (naturelle, pollution automobile), les peintures anciennes (poussières), l'eau de boisson ayant transité dans des canalisations en plomb, seule l'analyse isotopique permettra de prendre position et de mettre en évidence une origine prépondérante. Des exemples sont présentés dans le texte. 2. Un élément léger, qui normalement devrait conduire à des ségrégations isotopiques, mais qui ne précipite pas et ne s'adsorbe pas ou très peu, c'est le cas du bore. - Le bore peut aussi avoir plusieurs origines. Les produits lessiviels dont le bore ne provient que de Californie pour la plus grande partie et de Turquie pour le reste. Ce bore a une signature isotopique différente de celle du bore trouvé en France. Cette méthode nous permet donc de distinguer le bore utilisé pour l'agriculture ou le bore naturel, du bore utilisé dans les formulations de produits de nettoyage.

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Sgarbi, Ricardo, Huong Doan et Marian Chatenet. « Carbon-Capped Monometallic and Bimetallic Catalysts for Hydrogen Oxidation Reaction (HOR) and Their Positive Features on Durability in Alkaline Conditions ». ECS Meeting Abstracts MA2022-01, n^o 45 (7 juillet 2022) : 1902. http://dx.doi.org/10.1149/ma2022-01451902mtgabs.

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Alkaline fuel cells (AFC) and anion exchange membrane fuel cells (AEMFC) have exhibited attractive advantages versus their acid counterparts, including the strategical possibility of using PGM-free catalysts in the electrode composition.[1,2] PGM-free catalysts remain a challenge regarding the hydrogen oxidation reaction (HOR) catalysis, due to the reduced initial and long-term performance so far.[3,4] PGM-based materials have the highest HOR performances,[5] but Pt- and Pd-based catalysts undergo detrimental metallic nanoparticles detachment from the carbon support and agglomeration (in minor extent) upon extended potential cycling in the alkaline environments.[6,7] In this work, we explore the effect of long-term durability on the nanoparticles wrapped by a carbon layer, labeled here as capped catalysts; two different types of carbon-capped catalysts are evaluated, such as monometallic (PdG2/C) and bimetallic (PdNiG2/C) against their commercial ones (Pd/C and PdNi/C from Premetek). All the catalysts were evaluated in RDE set-up, in couple with IL-TEM, XPS and ICP-MS techniques for before and after accelerated stress test (0.1 – 1.23 V vs. RHE – 3s each potential), up to 6000 cycles. The durability enhancement is achieved when: i) there is a carbon-cap and ii) there is a second metal (i.e. Ni) on the surface of Pd. Thus, in the case of carbon-capped bimetallic (PdNiG2/C), there is a double protection of the Pd nanoparticles (from the carbon-cap and the presence of nickel). In the same time, the HOR activity is high. In the end, the best compromise of durability follows the trend: PdNiG2/C > PdNi/C > PdG2/C > Pd/C. These positive features of the carbon-capped bimetallic material open the way to the design of robust catalysts for highly-durable anodes for alkaline fuel cell systems. [1] D. R. Dekel, J. Power Sources 2018, 375, 158–169. [2] E. Wagner, H. ‐J. Kohnke, Fuel Cells 2020, 1–12. [3] A. G. Oshchepkov, G. Braesch, A. Bonnefont, E. R. Savinova, M. Chatenet, ACS Catal. 2020, 10, 7043–7068. [4] W. E. Mustain, M. Chatenet, M. Page, Y. S. Kim, Energy Environ. Sci. 2020, 13, 2805–2838. [5] W. Sheng, M. Myint, J. G. Chen, Y. Yan, Energy Environ. Sci. 2013, 6, 1509–1512. [6] C. Lafforgue, F. Maillard, V. Martin, L. Dubau, M. Chatenet, ACS Catal. 2019, 9, 5613–5622. [7] A. Zadick, L. Dubau, N. Sergent, G. Berthomé, M. Chatenet, ACS Catal. 2015, 5, 4819–4824.

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Bazan, Antony, Gonzalo García, Angélica María Baena-Moncada et Elena Pastor. « Ni Foam-Supported NiMo Catalysts for the HER ». ECS Meeting Abstracts MA2022-01, n^o 34 (7 juillet 2022) : 1390. http://dx.doi.org/10.1149/ma2022-01341390mtgabs.

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In the last years, “green hydrogen” fuel had gained a strong relevance due to its potential as friendly-environment energy source to replace fossil fuels. “Green hydrogen” fuel is obtained from water splitting by electrolysis, which can be powered by renewable energy sources, avoiding the emission of CO2 gas as by-product [1]. Particularly, alkaline water splitting has been, extensively, reported as the most sustainable and low-cost route for “green hydrogen” production. However, either oxygen (OER) or hydrogen evolution (HER) half-reaction can be limited by low-relative abundance of noble metals used as commercial electrocatalysts, such as, the benchmarking IrO2||Pt two-electrode couple of 1.57 V at 10 mA cm-2 [2]. Hence the design of non-noble electrocatalysts has gained relevance due to their remarkable electroactivity and high abundance. Mainly, Ni, Fe, Co and/or Mo - based electrocatalysts showed outstanding performance toward the HER. Indeed, theoretical studies indicated that their metallic surfaces promote the hydrogen electro-adsorption as like-metal hydride [M-H], hydroxide [M-OH] and or oxyhydroxide [MOOH] species [3–5]. Consequently, a controlled charge transfer in a two-step mechanism allows a fast electroreduction of water to the desired “green hydrogen” gas. Herein, we report the synthesis of bimetallic nanostructures, which are produced by thermal-controlled chemical reduction of their precursor salts (NiCl2, Na2MoO4) on the activated nickel foam (NiFA) surface at different highest temperatures (60, 70 and 80 ºC) [4,6]. Therefore, electrocatalysts were labeled as NiMo60/NiFA (60ºC), NiMo70/NiFA (70 ºC) and NiMo80/NiFA (80 ºC). Materials were physicochemical characterized by XRD, SEM, ICP-MS, infrared and Raman spectroscopy, and the HER on the synthesized catalysts in alkaline media was monitored by Differential Electrochemical Mass Spectrometry (DEMS) and in-situ Raman spectroscopy (Fig. a-d). Main results reveal outstanding electrochemical performance toward the HER on the novel nanomaterials, which is mainly influenced by the highest temperature reached at the synthesis procedure. Furthermore, DEMS indicate similar reaction mechanism for the HER at all catalysts and an increment of the catalytic activity rising the temperature at the synthesis stage. References Germscheidt RL, Moreira DEB, Yoshimura RG, Gasbarro NP, Datti E, dos Santos PL, et al. Hydrogen Environmental Benefits Depend on the Way of Production: An Overview of the Main Processes Production and Challenges by 2050. Adv Energy Sustain Res. 2021;2(10):2100093(1-20). Li X, Zhao L, Yu J, Liu X, Zhang X, Liu H, et al. Water Splitting: From Electrode to Green Energy System. Nano-Micro Lett. 2020;12(1):1-29 Abbas MA, Bang JH. Rising Again: Opportunities and Challenges for Platinum-Free Electrocatalysts. Chem Mater. 2015;27(21):7218–7235. Nairan A, Zou P, Liang C, Liu J, Wu D, Liu P, et al. NiMo Solid Solution Nanowire Array Electrodes for Highly Efficient Hydrogen Evolution Reaction. Adv Funct Mater. 2019;29(44):1903747(1–8). Chen G, Wang T, Zhang J, Liu P, Sun H, Zhuang X, et al. Accelerated Hydrogen Evolution Kinetics on NiFe-Layered Double Hydroxide Electrocatalysts by Tailoring Water Dissociation Active Sites. Adv Mater. 2018;30(10):1706279(1-7). Cao J, Li H, Pu J, Zeng S, Liu L, Zhang L, et al. Hierarchical NiMo alloy microtubes on nickel foam as an efficient electrocatalyst for hydrogen evolution reaction. Int J Hydrogen Energy. 2019;44(45):24712–247128. Acknowledgments The Peruvian Fund for Science and Technology (PROCIENCIA) and the Peruvian Minister of Education (MINEDU) by supporting the present work under project 298-2019 FONDECYT and the Doctoral Program with contract 237-2015. The Spanish Ministry of Economy and Competitiveness (MINECO) under project ENE2017-83976 -C2-2-R (FEDER) (co-funded by FEDER). G.G. acknowledges the “Viera y Clavijo” program (ACIISI & ULL), NANOtec, INTech, and Cabildo de Tenerife for laboratory facilities. Authors would like to acknowledge the use of SEGAI—ULL facilities. Figure 1

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Volk, Emily K., Rebecca R. Beswick, Stephanie Kwon et Shaun M. Alia. « Electrochemical Activation of NiFe₂O₄ for the Oxygen Evolution Reaction in Alkaline Media ». ECS Meeting Abstracts MA2023-01, n^o 36 (28 août 2023) : 2067. http://dx.doi.org/10.1149/ma2023-01362067mtgabs.

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Electrochemical H2 production via low temperature H2O electrolysis is a promising strategy to facilitate decarbonization across sectors;1 however, current high-performing proton exchange membrane (PEM) electrolyzers require the use of expensive and rare platinum-group metals (PGMs) for catalysts and hardware, limiting scale up feasibility.2 More recently, anion exchange membrane (AEM) electrolyzers have emerged as an alternative strategy, combining the zero-gap approach employed by PEM with operation in an alkaline environment where many non-PGMs are thermodynamically stable.3 In fact, oxides of first row transition metals including Ni, Fe, and Co have been proposed as promising anode catalyst alternatives to IrO2 in AEM electrolyzers.4–7 However, these materials suffer from high overpotentials (> 300 mV @ 10 mA/cm2)8 and kinetic improvements are needed to facilitate the deployment of this technology. Ni-Fe oxides have gained particular attention due to their high ex-situ activities and typically low material criticality compared to IrO2 or other non-PGMs such as Co.9 Ni and Fe are known to have a synergistic effect, with trace amounts of Fe in Ni catalysts leading to increased OER activity.10 However, the mechanism behind the improved performance and the optimal Fe content is heavily debated in the literature;11 for example, this activity enhancement has been attributed to increased electrical conductivity with increasing Fe content,10 stabilization of the Ni4+ state,12 and a shift of the Ni (II/III) redox couple.13 Furthermore, these studies have evaluated Ni-Fe catalysts in their metallic or oxy(hydroxide) forms, although device-level conditioning may passivate near-surfaces and minimize performance differences between catalysts with difference ex-situ oxide content.14 Uncovering how Fe content changes over time-on-stream for nanoparticle oxides and correlating this to changes in activity is needed to facilitate optimization of these materials at the device level. To this end, this work evaluated the stability of NiFe2O4 nanoparticles (30 nm) in alkaline environments, correlating changes in Fe composition to changes in activity. All tests were performed in a rotating disc electrode cell with Au working electrode (0.193 cm2), Au counter electrode, and reversible hydrogen reference electrode. Tests were performed in 0.1 M NaOH electrolyte at room temperature with a catalyst loading of 17.8 μgM/cm2. We found that the activity of NiFe2O4 improved over time-on-stream (+ 80 % in current at 1.65 V after 13.5 h) concurrent with a dissolution of Fe (2 – 8 wt% Fe loss). We hypothesize that the Fe content in NiFe2O4 (48 wt% Fe) was prohibitively high, and that dissolution of Fe shifted this value closer to optimum, resulting in higher activity. For NiFe (oxy)hydroxide materials, optimal Fe content has been reported at 15 - 25 wt% Fe.10 However, this value likely changes depending on the structure of the material and, relatedly, the relative abundances of Ni and Fe on the surface. We further looked at the effect of longer time on stream at 1.8 V (13.5 h – 27 h) and potentiodynamic cycling (1.4 - 1.8 V, 1.4 – 2.0 V, 0.0 – 2.0 V; 13.5 h) on NiFe2O4 stability. The results, in turn, showed that catalyst reactivity for OER improved over time-on-stream by 50 – 80% for potentiostatic holds and by upwards 500% for cycling tests (Fig. 1). This activity improvement was found to be concurrent with Fe dissolution (determined from ICP-MS), which ranged from 2 – 8 wt% Fe loss for the potentiostatic stress test to upwards of 40 wt% Fe loss for the cycling tests. Increased time on stream (13.5 – 27 h) was found to not significantly impact the activity enhancement. These results show a correlation between Fe dissolution and activity improvement and suggest that the activity of nanoparticle NiFe2O4 oxides may be electrochemical activated via this method, providing new insights into the viability of NiFe oxides as alternatives to IrO2 for OER. [1] Borup et al., Electrochem. Soc. Interface 2021, [2] IRENA Green Hydrogen Cost Reduction - Scaling up Electrolyzers to Meet the 1.5C Climate Goal 2020, [3] Pourbaix, Atlas of Electrochemical Equilibria in Aqueous Solutions, 1974, [4] Suen et al., Chem. Soc. Rev. 2017, [5] Plevová et al., J. Power Sources 2021, [6] Burke et al., Chem. Mater. 2015, [7] Anderson et al., J. Electrochem. Soc. 2020, [8] McCrory et al., J. Am. Chem. Soc 2015, [9] European Commission, Report on Critical Raw Materials for the EU 2018, [10] Trotochaud et al., J. Am. Chem. Soc. 2014, [11] Anantharaj et al., Nano Energy 2021, [12] Li et al., Proc. Natl. Acad. Sci. 2017, [13] Görlin et al., J. Am. Chem. Soc. 2016, [14] Alia et al., J. Electrochem. Soc. 2019 Figure 1

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VACCHINA, Véronique, Martine POTIN-GAUTIER et Fabienne SEBY. « Couplage HPLC-ICP-MS et application à la spéciation ». Techniques d'analyse, avril 2019. http://dx.doi.org/10.51257/a-v2-p3872.

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POTIN-GAUTIER, Martine, et Corinne CASIOT. « Couplage HPLC-ICP-MS et application à la spéciation ». Techniques d'analyse, décembre 2001. http://dx.doi.org/10.51257/a-v1-p3872.

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PAUCOT, Hugues, et Martine POTIN-GAUTIER. « ICP-MS : couplage plasma induit par haute fréquence – spectrométrie de masse ». Techniques d'analyse, juin 2010. http://dx.doi.org/10.51257/a-v3-p2720.

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Gimenez-Ingalaturre, Ana C., Isabel Abad-Álvaro, Pilar Goñi, Kharmen Billimoria, Heidi Goenaga-Infante et Francisco Laborda. « Performance of single-cell ICP-MS for quantitative biodistribution studies of silver interactions with bacteria ». Journal of Analytical Atomic Spectrometry, 2024. http://dx.doi.org/10.1039/d3ja00378g.

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Single-cell inductively couple plasma mass spectrometry (SC-ICP-MS) method development for the study of silver interactions with bacteria to provide information about silver biodistribution in bacteria and spheroplasts.

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Dowben, Sydney Ariane, Suhee Choi, Jim Steppan, Sang Eun Bae, Olivia Dale, Tom Meaders, Mario Gonzalez, J. Paulo Perez et Michael Simpson. « Electrochemical Analysis of Metal Stability in Candidate Reference Electrode Fluoride Salts (FLiNaK + 1 wt% AgF, MnF₂, or NiF₂) ». Journal of The Electrochemical Society, 22 janvier 2024. http://dx.doi.org/10.1149/1945-7111/ad2151.

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Abstract We investigated the long-term stability of Ag/AgF, Mn/MnF₂, and Ni/NiF₂ redox couples for use in reference electrodes (REs) for molten fluoride salt systems. A quasi-RE system was used with FLiNaK + 1 wt% AgF, MnF₂, or NiF₂, to evaluate the stability of various metals that may be used for molten fluoride salt RE design. Cyclic voltammetry was used to measure changes in the electrochemical response of different metal wires in the melts tested. Salt samples were analyzed for dissolved metal and oxide concentrations via ICP-MS and combustion analysis, respectively. To observe the surface morphology of the electrodes used in the Ag/AgF test, cross-sectional imaging of the electrodes was provided via SEM. Resulting electrochemical measurements show that a RE constructed using a Mn/MnF₂ or Ni/NiF₂ redox couple should perform with greater potential stability compared to a Ag/AgF redox couple. The instability of the Ag/AgF redox couple is due to the strong oxidizing property of the AgF salt compared to the MnF₂ and NiF₂ salts. SEM results from the Ag/AgF test indicate that Ag metal is corrosion resistant, but having AgF in the salt causes it to be corrosive towards other metals (Ni and W) that are considered relatively corrosion resistant.

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Diayi, Anslem, et Michael Gbadebo. « Geochemical Pollution Assessment of Sediment Metal from Lower Region of the Ogun River, Nigeria ». Applied Environmental Research, 17 octobre 2014, 13–18. http://dx.doi.org/10.35762/aer.2014.36.4.2.

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From depths of 0-5 cm, 5-10 cm and 10-15 cm, sediment samples were collected from three locations in the lower region of the Ogun River Basin, namely Mokoloki, Oke-Oko and Kara. The samples were obtained using Van Veen sediment grab after which they were stored in well labeled polythene bags for onward transportation to the laboratory. For pH and conductivity, samples were determined in-situ using standard methods by the American Public Health Association of 1992 while Organic Carbon was determined by the Wakley Method. The sediments were then air dried before analysis for particle size and metal concentration. Induced Couple Plasma Mass Spectrometry (ICP/MS) was used to determine metal concentrations. Data obtained were used to determine the geochemical pollution intensities for the various sediment samples. The results of physicochemical analyses revealed all sediment samples to be alkaline, while particle size analysis showed that the sediments were sandy. All metal concentrations for Cu, Pb, As, Zn, Hg, Cd, and Cr were lower than the Environment Canada Sediment Quality Guideline standards of 35.70 ppm, 35.00 ppm, 0.60 ppm, 123.00 ppm, 5.90 ppm, 0.17 ppm and 37.50 ppm, respectively. The low metal concen-trationsobtained from the trace metal analyses were confirmed with an ‘unpolluted status’ obtained for all sediment samples analyzed using the geochemical accumulation index formula. Results showed that metal concentrations in these areas are low and do not pose a threat to the survival of living organisms living in sediments or the surrounding environment.

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Andriyono, Sapto, Nuning Vita Hidayati, Mirna Fitrani, Latifah A. Manaf, Ahasan Habib, Umi U. Dewi et Saadah Mukadar. « Ecological risks assessment of fishery commodities from heavy metal in The East Java Province, Indonesia ». Journal of Water and Land Development, 9 janvier 2024, 183–93. http://dx.doi.org/10.24425/jwld.2024.149120.

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Heavy metals are a crucial group of chemicals extensively used in materials to meet human needs, eventually leading to contamination of aquatic ecosystems and accumulation in organism’s tissues. Heavy metals enter the aquatic ecosystem from various sources. Those metals that pollute aquatic waters are deposited in sediments, remain dissolved in water or accumulate in the food web of aquatic organisms. Benthic biota is believed to accumulate the highest levels of these metals, while other aquatic animals, such as fish, shrimp, and macroalgae, serve as significant sources of heavy metals intake through food and the environmental exposure. Ina study conducted in and around the east Java, Indonesia, the concentration of heavy metals in commercially important fish species, shellfish, and macroalgae were evaluated using an inductive couple plasma-mass spectrometer (ICP-MS). This study is very important because fishery resources are not only vital for exports but also serve as a primary source of essential food for local communities. The results showed that heavy metal concentration (Pb, Cd, and Hg) in samples were 12.3 mg∙dm –3, 0.171 mg∙dm –3, and undetectable, respectively. This study showed that different metals were present in the samples at different levels, all of which fell within the maximum residual levels set by the EU and USFDA. The results of an analysis of food safety based on the Hazard Index showed values below 1 point, indicating that fishery products (fish, shrimp, and macroalgae) from the East Java Province are generally safe for human consumption.

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Hoerler, J., A. Von Quadt, R. Burkhard, I. Peytcheva, V. Cvetkovic et T. Baker. « The Karavansalija Mineralized Center at the Rogozna Mountains in SW Serbia : Magma Evolution and Time Relationship of Intrusive Events and Skarn Au ± Cu–Pb–Zn Mineralization ». Frontiers in Earth Science 9 (18 janvier 2022). http://dx.doi.org/10.3389/feart.2021.798701.

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The Karavansalija Mineralized Center (KMC) with its Au–Cu skarn mineralization associated with the Rogozna Mountains magmatic suite in southwestern Serbia belongs to the Oligocene Serbo-Macedonian magmatic and metallogenic belt (SMM-MB). Samples from intrusive and volcanic rocks at the KMC show typical arc signatures of subduction-derived magmas through enrichment in large-ion lithophile elements (LILE) and depletion of high–field strength elements (HFSE). The magmas developed a high-K (calc-alkaline) fractionation trend and evolved toward shoshonitic compositions. Whole-rock trace element data suggest plagioclase-absent, high-pressure amphibole ± garnet fractionation that generates adakite-like hydrous magmas during evolution in lower crustal magma chambers. Zircon LA–ICP–MS and high-precision CA–ID–TIMS dating together with zircon trace elements and Hf isotope measurements were carried out in order to couple the geochronologic and geochemical evolution of the KMC. The results suggest that magmatism starts around 29.34 Ma with granitic to rhyodacitic subvolcanic intrusions followed by a more evolved magmatic intrusion that was emplaced into Cretaceous limestone, generating a widespread skarn alteration at ca. 28.96 Ma. After a period of quiescence of about 1.2 My, either another magma body evolved or the same upper crustal magma chamber was recharged and also likely partly reactivated older plutonic rocks as indicated by xenocrysts. The REE ratios shift from apatite, titanite ± amphibole-dominated fractionation of the older magmatic event to crystallization of allanite, efficiently depleting the LREE and Th/U in the younger upper crustal magma. After a lamproite-like melt was injected, the increased heat and fluid pressure led to the expulsion of a quartz-monzonite porphyritic stock at ca. 27.72 Ma, strongly interacting with the skarns and established a fertile hydrothermal system. Soon after a non-mineralized second pulse of some porphyry dykes cut the previous phenocryst-rich “crowded” porphyries and skarns at ca. 27.60 Ma, thus bracketing the maximum timespan of ore mineralization to about 112 ± 45 Ka. Increased contribution of a lamproite-like melt is inferred from the presence of phlogopite micro-phenocrysts, phlogopitization of biotite, and diopside clusters in the latest porphyry dykes. There is a trend of increased crustal assimilation from the oldest volcanic phase to the emplacement of the youngest porphyry dykes recorded by ɛ-Hf of the zircons. Oligocene occurrences of significant base metal mineralization within Serbia, northern Macedonia, and Greece, e.g., Crnac, Rudnik, Veliki Majdan, Stratoniu, or the Cu–Au porphyry at Buchim (northern Macedonia), are all associated with trachy-andesitic (quartz latitic) porphyry dykes, which originated through post-collisional tectonic settings or upper plate extension involving reworking of crustal arc-derived rocks and partial melting of the mantle wedge. This study demonstrates that on the basis of field relationships and the application of high-precision CA-ID-TIMS zircon age data, pulses of porphyry dykes of a 10ka age range can be distinguished, and the timing of mineralization can be parenthized.

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