Transition metal (e.g. Ni) ions dissolved from layered‐structured Ni‐rich cathodes can migrate to the anode side and accelerate the failure of lithium‐ion batteries. The investigations of the impact ...and distribution of Ni species on the solid electrolyte interphase (SEI) on the anode are crucial to understand the failure mechanism. Herein, we used time‐of‐flight secondary ion mass spectroscopy (TOF‐SIMS) coupled with multivariate curve resolution (MCR) analysis to intuitively characterize the distribution of Ni species in the SEI. We find that the SEI on the graphite electrode using an EC‐based electrolyte exhibits a multi‐stratum structure. During accelerated aging of the LiNi0.88Co0.08Mn0.04O2/graphite full cell, the dissolution of Ni aggravates significantly upon cycling. A strong correlation between the dissolved‐Ni and organic species in the SEI on graphite is illustrated. The ion‐exchange reaction between Ni2+ and Li+ ions in the SEI is demonstrated to be the main reason for the increase of SEI resistivity.
Time‐of‐flight secondary ion mass spectroscopy coupled with multivariate curve resolution analysis is used to investigate the impact and distribution of Ni species on the solid electrolyte interphase (SEI). During accelerated aging of the LiNi0.88Co0.08Mn0.04O2/graphite full cell, the dissolution of Ni aggravates significantly upon cycling and a strong correlation between the dissolved‐Ni and organic species in the SEI on graphite is found.
This Feature aims at giving an overview of different possibilities for quantitatively comparing the results obtained from LC−HRMS-based nontargeted analysis. More specifically, quantification via ...structurally similar internal standards, different isotope labeling strategies, radiolabeling, and predicted ionization efficiencies are reviewed.
The isotopic compositions of the natural potassium chloride sample NIST SRM 999b, and the isotopically enriched material GSC K-40 that is used in an ongoing study of the half-life of 40K by decay ...counting, were determined using total evaporation thermal ionisation mass spectrometry (TE-TIMS) and incipient emission thermal ionisation mass spectrometry (IE-TIMS). Both methods were comprehensively calibrated for precision and accuracy by multiple analyses against gravimetrically prepared synthetic mixtures of enriched 39K and 41K. These mixtures of enriched isotopic materials characterised for purity and stoichiometry, have 41K/39K with uncertainty of ca. 0.02%, and can be used for calibration of either TIMS or MC-ICPMS (multi-collector inductively coupled plasma mass spectrometry) measurements of K isotopic composition independently of the currently accepted IUPAC value. The TE-TIMS and IE-TIMS analyses of potassium using some, but not all, combinations of loading medium, filament configuration, and data processing methods can yield accurate “absolute” isotopic compositions without standardisation. The 41K/39K ratio in NIST SRM 999b determined in this study with TE-TIMS and IE-TIMS has the value of 41K/39K = 0.072247 ± 0.000086, 95% confidence level), which is consistent within 95% confidence limits with the isotopic composition of this material derived from the calibration of Garner et al. (1975), which serves as the basis of the current IUPAC recommendation and is used as a reference in the rapidly growing field of potassium stable isotope geochemistry. The isotopic abundance of 40K in the enriched GSC K-40 is determined with the total uncertainty of 0.075% (95% confidence level), and is suitable for precise calculation of the half-life of 40K in our ongoing decay counting study.
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Biologic scaffolds are derived from mammalian tissues, which must be decellularized to remove cellular antigens that would otherwise incite an adverse immune response. Although widely ...used clinically, the optimum balance between cell removal and the disruption of matrix architecture and surface ligand landscape remains a considerable challenge. Here we describe the use of time of flight secondary ion mass spectroscopy (ToF-SIMS) to provide sensitive, molecular specific, localized analysis of detergent decellularized biologic scaffolds. We detected residual detergent fragments, specifically from Triton X-100, sodium deoxycholate and sodium dodecyl sulphate (SDS) in decellularized scaffolds; increased SDS concentrations from 0.1% to 1.0% increased both the intensity of SDS fragments and adverse cell outcomes. We also identified cellular remnants, by detecting phosphate and phosphocholine ions in PAA and CHAPS decellularized scaffolds. The present study demonstrates ToF-SIMS is not only a powerful tool for characterization of biologic scaffold surface molecular functionality, but also enables sensitive assessment of decellularization efficacy.
We report here on the use of a highly sensitive analytical technique, time of flight secondary ion mass spectroscopy (ToF-SIMS) to characterize detergent decellularized scaffolds. ToF-SIMS detected cellular remnants and residual detergent fragments; increased intensity of the detergent fragments correlated with adverse cell matrix interactions. This study demonstrates the importance of maintaining a balance between cell removal and detergent disruption of matrix architecture and matrix surface ligand landscape. This study also demonstrates the power of ToF-SIMS for the characterization of decellularized scaffolds and capability for assessment of decellularization efficacy. Future use of biologic scaffolds in clinical tissue reconstruction will benefit from the fundamental results described in this work.
Aim
Biodegradation is a cost‐effective and eco‐friendly treatment for oil‐contaminated materials using microorganisms. Bacteria and fungi can degrade petroleum by using it as an energy source and ...this may provide an enormous scope to remediate soils contaminated with petroleum and oil. This study aimed to assess the biodegradation of petroleum hydrocarbons by certain Cladosporium species.
Methods and results
By using traditional and spectroscopic assessment analysis, qualitative screening was carried out using Cladosporium spores isolated from air and cultured on mineral salt medium supplemented with petroleum hydrocarbon as the sole carbon source, followed by quantitative assessment using gas chromatography–mass spectroscopy. Nineteen Cladosporium strains from a total of 212 isolates exhibited remarkable capability to degrade petroleum hydrocarbon, representing four species (C. herbarum, C. macrocarpum, C. sphaerospermum, and C. cladosporioides). The results were expressed in terms of biodegradation percentage and optical density of hydrocarbon using a standard calibration curve. The highest reduction of petroleum hydrocarbon was observed with five Cladosporium strains belonging to two species (C. sphaerospermum and C. cladosporioides).
Conclusion
This study succeeded in isolating several Cladosporium strains (from the air) with a high ability to degrade crude oil that can be used as biological agents to control petroleum pollution in soils and seas. The addition of a surfactant (Tween 80) enhanced the degradation of crude oil reaching a final concentration of 0.4%. Based on these results, the present study could indicate some unique prospects in the field of bioremediation and biodegradation of petroleum‐contaminated soil.
Significance and impact of study
This study gives unique prospects in the field of bioremediation and biodegradation of petroleum‐contaminated soil.
A systematic study on the Λ ground state binding energy of hyperhydrogen HΛ4 measured at the Mainz Microtron MAMI is presented. The energy was deduced from the spectroscopy of mono-energetic pions ...from the two-body decays of hyperfragments, which were produced and stopped in a 9Be target. First data, taken in the year 2012 with a high resolution magnetic spectrometer, demonstrated an almost one order of magnitude higher precision than emulsion data, while being limited by systematic uncertainties. In 2014 an extended measurement campaign was performed with improved control over systematic effects, increasing the yield of hypernuclei and confirming the observation with two independent spectrometers and two targets of different thicknesses. The analysis of these data is in agreement with the previously published value for the HΛ4 binding energy as well as with a consistent re-analysis of the 2012 data. When compared to the HeΛ4 binding energy from emulsion data, a large charge symmetry breaking effect in the A=4 hypernuclear system is confirmed.
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