scholarly journals Multi-Element Imaging of a 1.4 Ga Authigenic Siderite Crystal

Minerals ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1395
Author(s):  
Huajian Wang ◽  
Yuntao Ye ◽  
Yan Deng ◽  
Yuke Liu ◽  
Yitong Lyu ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Iron Reduction ◽  
Formation Mechanisms ◽  
Time Interval ◽  
Growth Environment ◽  
Inductively Coupled ◽  
Key Factor ◽  
Dissimilatory Iron Reduction ◽  
Plasma Mass Spectrometry ◽  
Isotope Evidence

Iron formations (IFs) are traditionally considered to be limited during 1.8−0.8 Ga. However, there are recent reports of siderite-dominated IFs within this time interval, such as the 1.40 Ga Xiamaling IF in North China and the 1.33 Ga Jingtieshan IF in Qilian. To further explore the crystallization and formation mechanisms of siderite, an authigenic siderite crystal from the Xiamaling IF was fully scanned using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Multi-element imaging with a spatial resolution of 5 μm revealed an obvious rim structure of the siderite crystal, which might record the crystallization and growth processes. The Al- and Fe-enriched zone in the core of siderite crystal might be an iron-bearing nucleus, and the formation of rim structure was related to the transition from a closed crystallization environment to a semi-closed growth environment. These results, combined with carbon isotope evidence from the siderites and surrounding shales, suggest that vigorous dissimilatory iron reduction that can provide Fe2+ and HCO3− to the pore water is a key factor to form the siderite-dominated Xiamaling IF.

scholarly journals Antioxidants and Health-Beneficial Nutrients in Fruits of Eighteen Cucurbita Cultivars: Analysis of Diversity and Dietary Implications

Molecules ◽  
2020 ◽  
Vol 25 (8) ◽  
pp. 1792 ◽  
Author(s):  
Anna Kostecka-Gugała ◽  
Michał Kruczek ◽  
Iwona Ledwożyw-Smoleń ◽  
Paweł Kaszycki
Keyword(s):  
Phenolic Compounds ◽  
Inductively Coupled Plasma ◽  
High Performance ◽  
The Elderly ◽  
Antioxidant Power ◽  
Inductively Coupled ◽  
Key Factor ◽  
Ferric Reducing Antioxidant Power ◽  
Plasma Mass Spectrometry ◽  
Molecular Damage

Aging is accompanied by gradual accumulation of molecular damage within cells in response to oxidative stress resulting from adverse environmental factors, inappropriate lifestyle, and numerous diseases. Adequate antioxidant intake is a key factor of proper diet. The study aimed to assess the antioxidant/antiradical capacities of Cucurbita fruits (18 cultivars of the species: C. maxima Duch., C. moschata Duch., C. pepo L., and C. ficifolia Bouché) grown in central Europe. The analyses were based on the FRAP (ferric reducing antioxidant power), CUPRAC (cupric ion reducing antioxidant capacity), and DPPH (2,2-diphenyl-1-picrylhydrazyl radical) assays. The content of phenolic compounds and β-carotene was evaluated with HPLC (high performance liquid chromatography), while the main macro- and micronutrients by ICP-OES (inductively coupled plasma mass spectrometry). The results revealed high intraspecies variability within the Cucurbita genus. The Japanese ‘Kogigu’ fruits were distinguished as extraordinary sources of phenolic compounds, including syringic and protocatechuic acids, catechin, and kaempferol. Another popular cultivar ‘Hokkaido’ exhibited the highest antioxidant and antiradical capacities. Most of the fruits proved to be rich sources of zinc and copper. The obtained data are discussed in the context of optimized nutrition of the elderly and suggest that Cucurbita fruits should become daily components of their diet.

Metal-Organic Frameworks vs. Buffers: Case Study of UiO-66 Stability

2020 ◽  
Author(s):  
Daniel Bůžek ◽  
Slavomír Adamec ◽  
Kamil Lang ◽  
Jan Demel
Keyword(s):  
Inductively Coupled Plasma ◽  
Buffer Capacity ◽  
Metal Organic Framework ◽  
Metal Organic Frameworks ◽  
Analytical Techniques ◽  
Aqueous Dispersions ◽  
Inductively Coupled ◽  
Plasma Mass Spectrometry ◽  
Metal Organic

<div><p>UiO-66 is a zirconium-based metal-organic framework (MOF) that has numerous applications. Our group recently determined that UiO-66 is not as inert in aqueous dispersions as previously reported in the literature. The present work therefore assessed the behaviour of UiO-66 in buffers: 2-amino-2-(hydroxymethyl)-1,3-propanediol (TRIS), 4-(2-hydroxyethyl)piperazine-1-ethane sulfonic acid (HEPES), N-ethylmorpholine (NEM) and phosphate buffer (PB), all of which are commonly used in many UiO-66 applications. High pressure liquid chromatography and inductively coupled plasma mass spectrometry were used to monitor degradation of the MOF. In each buffer, the terephthalate linker was released to some extent, with a more pronounced leaching effect in the saline forms of these buffers. The HEPES buffer was found to be the most benign, whereas NEM and PB should be avoided at any concentration as they were shown to rapidly degrade the UiO-66 framework. Low concentration TRIS buffers are also recommended, although these offer minimal buffer capacity to adjust pH. Regardless of the buffer used, rapid terephthalate release was observed, indicating that the UiO-66 was attacked immediately after mixing with the buffer. In addition, the dissolution of zirconium, observed in some cases, intensified the UiO-66 decomposition process. These results demonstrate that sensitive analytical techniques have to be used to monitor the release of MOF components so as to quantify the stabilities of these materials in liquid environments.</p></div>

Single Particle Inductively Coupled Plasma Mass Spectrometry: Investigating Nonlinear Response Observed in Pulse Counting Mode and Extending the Linear Dynamic Range by Compensating for Dead Time Related Count Losses on a Microsecond Timescale

2019 ◽  
Author(s):  
Ingo Strenge ◽  
Carsten Engelhard
Keyword(s):  
Mass Spectrometry ◽  
Inductively Coupled Plasma ◽  
Nonlinear Response ◽  
Dynamic Range ◽  
Dead Time ◽  
Inorganic Nanoparticles ◽  
Linear Dynamic Range ◽  
Inductively Coupled ◽  
Icp Ms ◽  
Plasma Mass Spectrometry

<p>The article demonstrates the importance of using a suitable approach to compensate for dead time relate count losses (a certain measurement artefact) whenever short, but potentially strong transient signals are to be analysed using inductively coupled plasma mass spectrometry (ICP-MS). Findings strongly support the theory that inadequate time resolution, and therefore insufficient compensation for these count losses, is one of the main reasons for size underestimation observed when analysing inorganic nanoparticles using ICP-MS, a topic still controversially discussed.</p>

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