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Grape molasses (GM), produced from grapes, is a traditional Iranian food and is widely consumed in Iran. However, GM adulteration is among the most widespread illegitimate procedures involving contamination of food with foreign materials, such as adding sugar–water solution, date syrup, sugar beet syrup, and grape sauce. This study used stable carbon 13C/12C isotope ratio analysis method to detect adulteration of GM samples with glucose syrups (GS), fructose syrups (FS), and beet sugar syrups (BS) at the ratio of 0%, 10%, 30%, and 50% (by weight). Physicochemical properties of GM including °Brix, conductivity, specific gravity, pH, moisture content, ash content, hydroxymethyl furfural, sugar content, and rheological properties of samples were investigated. The δ13C isotope ratio of the GM was determined as −26.61%, that of the GS as −13.23%, that of the FS as −13.42%, and that of the BS as −16.58%. The δ13C isotope ratio increased by the addition of adulterant syrups to GM. The addition of each adulterant syrup had a different effect on the physicochemical parameters; however, the °Brix and specific gravity had a positive correlation with the δ13C isotope ratio results. The magnitudes of G' and G" increase with an increase in frequency representing the viscoelastic behavior of samples. The obtained results of this study suggest the use of δ13C isotope ratio method as a fast and accurate method to investigate the adulteration of grape molasses. [ABSTRACT FROM AUTHOR]

Particulate matter (PM) in the air has significant implications for human health and the environment, particularly in urban areas with high concentrations. This study focuses on the isotopic (δ13C and δ15N), elemental (CNS) as well as the total carbon to total nitrogen ratio (TC/TN) characterization of PM in Trombay, Mumbai. Monthly atmospheric dust samples were collected from 2016 to 2020 during the premonsoon and postmonsoon seasons. The average elemental concentrations for premonsoon samples were N (1.73% ± 0.25%), C (7.38% ± 0.72%), S (0.84% ± 0.13%), and TC/TN ratio (4.38 ± 0.86). For postmonsoon samples, the average elemental concentrations were N (1.47% ± 0.185%), C (6.95% ± 1.04%), S (0.84% ± 0.13%), and TC/TN ratio (4.80 ± 0.94). The average δ13C values for premonsoon and postmonsoon seasons were −24.31 ± 1.15‰ and −24.56 ± 1.20‰, respectively. The average δ15N values for premonsoon and postmonsoon seasons were 5.22 ± 1.92‰ and 4.57 ± 1.32‰, respectively. The results showed variations in elemental concentrations between the seasons, with higher values observed in premonsoon samples which can be attributed to increased dust generation from land and sea. Overall, this study provides insights into the local sources and characteristics of PM in the Trombay area and highlights the importance of long-term monitoring to understand the seasonal variations in PM composition.

The Sor and Gebba watershed plays a crucial role in the water resources of the Baro-Akobo River Basin. However, various factors have had a detrimental effect on the watershed. Unplanned groundwater extraction, wetland drainage, surface water pollution, and land use changes have all intensified due to population growth, urbanization, commercial farms, industrial development, poor water resources management, and improvements in living standards. This research utilized major hydrochemical ions and environmentally stable isotopes to elucidate the interaction between groundwater and surface water in the watershed, which are reliable tracers in various hydrologic processes. During the 2020 wet season and 2022 dry season, over 25 meteoric water samples were collected from different locations for hydrochemical and isotopic analysis. The hydrochemical analysis revealed that the dominant water type is Ca–Mg–HCO3−. Among the anions, HCO3− was the most dominant, followed by NO3−, Cl−, and SO42−, and those of cations Ca2+, followed by Na+, Mg2+, and K+. The spatial analysis of environmentally stable isotopes confirmed the interaction between groundwater and surface water in the watershed. The quality of groundwater is primarily influenced by rock-water interaction (Gibb's diagram) and, to some extent, by evaporation (Isotope study). A graph of the water samples closely aligned with the Addis Ababa-local meteoric water line indicates their meteoric origin. However, there was a slight deviation to the left due to the effects of distance and altitude. The isotopic correlation further supported the interaction between different water sources. [ABSTRACT FROM AUTHOR]

Mobile proximal gamma-ray spectrometry (GS) is an emerging approach to estimate soil texture directly in the field. It relies on gamma radiation emitted during the natural decay of potassium-40 (K-40) and other isotopes. The K-40 counts are correlated with total K content, mineralogical soil composition and therefore with soil texture. Yet, it is not clear if K fertilisation impacts the ratio of K-40 to total K which would necessitate to take the fertilisation history into account for soil sensing applications. To elucidate this question, a well-documented long-term experiment was selected. The soils of the Rengen grassland experiment (55 plots) were investigated for total K (XRF-K) and for K-40 via mobile proximal GS. No significant differences in XRF-K and K-40 were found between the treatments with and without K fertilisation, although formely published results point to negative and positive K balances, respectively. Fertiliser analysis revealed a ratio of K-40 to total K that was almost identical to the natural abundance of 0.0117%. It was concluded that it is not necessary to take K fertilisation history into account when predicting soil texture from mobile proximal GS on agricultural land for, e.g., precision farming purposes. [ABSTRACT FROM AUTHOR]

Geographical origin assessment of extra virgin olive oil (EVOO) is recognised worldwide as raising consumers' awareness of product authenticity and the need to protect top-quality products. The need for geographical origin assessment is also related to mandatory legislation and/or the obligations of true labelling in some countries. Nevertheless, official methods for such specific authentication of EVOOs are still missing. Among the analytical techniques useful for certification of geographical origin, nuclear magnetic resonance (NMR) and mass spectroscopy (MS), combined with chemometrics, have been widely used. This review considers published works describing the use of these analytical methods, supported by statistical protocols such as multivariate analysis (MVA), for EVOO origin assessment. The research has shown that some specific countries, generally corresponding to the main worldwide producers, are more interested than others in origin assessment and certification. Some specific producers such as Italian EVOO producers may have been focused on this area because of consumers' interest and/or intrinsic economical value, as testified also by the national concern on the topic. Both NMR- and MS-based approaches represent a mature field where a general validation method for EVOOs geographic origin assessment could be established as a reference recognised procedure.

Particulate matter (PM) in the air has significant implications for human health and the environment, particularly in urban areas with high concentrations. This study focuses on the isotopic (δ13C and δ15N), elemental (CNS) as well as the total carbon to total nitrogen ratio (TC/TN) characterization of PM in Trombay, Mumbai. Monthly atmospheric dust samples were collected from 2016 to 2020 during the premonsoon and postmonsoon seasons. The average elemental concentrations for premonsoon samples were N (1.73% ± 0.25%), C (7.38% ± 0.72%), S (0.84% ± 0.13%), and TC/TN ratio (4.38 ± 0.86). For postmonsoon samples, the average elemental concentrations were N (1.47% ± 0.185%), C (6.95% ± 1.04%), S (0.84% ± 0.13%), and TC/TN ratio (4.80 ± 0.94). The average δ13C values for premonsoon and postmonsoon seasons were −24.31 ± 1.15‰ and −24.56 ± 1.20‰, respectively. The average δ15N values for premonsoon and postmonsoon seasons were 5.22 ± 1.92‰ and 4.57 ± 1.32‰, respectively. The resultsshowed variationsin elemental concentrations between the seasons, with higher values observed in premonsoon samples which can be attributed to increased dust generation from land and sea. Overall, this study provides insights into the local sources and characteristics of PM in the Trombay area and highlights the importance of long-term monitoring to understand the seasonal variations in PM composition. [ABSTRACT FROM AUTHOR]

The intensity ratio (αI) and area ratio (αA) obtained using Raman spectroscopy are used widely to characterize the physical properties of gases, fluids, and solids, but the underlying parameters which affect their precision (σαI and σαA) have not been elucidated. We use simulations, experiments, and theoretical analyses to investigate the effects of instrumental performance, analytical conditions, and sample size on σαI and σαA. We identified the parameters which strongly influence σαI: (1) the weaker peak intensity Iw; (2) the ratio of the bandwidth to pixel resolution of the weaker peak Γw/Δxw; (3) the degree of detector saturation; (4) σD2+σR2/σS2 with readout noise σR, dark noise σD, and shot noise σS; (5) drift; and (6) sample size. Theoretical and simulation results show that, when Γw/Δxw ≪ (Γs/Δxs)/αI, increasing Iw or Γw/Δxw by n times can improve σαI by a factor of n. Results showed that σD2+σR2/σS2 is a measure of how much the achievable σαI in the experiment differs from that under ideal analytical conditions (i.e., σD2+σR2≪σS2). When σD2+σR2≪σS2 is not the case (i.e., when Iw is low), reducing σD or σR by decreasing the readout speed, setting a lower charge coupled device (CCD) sensitivity, reducing number of readouts, or narrowing vertical binning width can improve σαI. We demonstrated that evaluations of σαI or σαA based on small sample sizes can engender physically unattainable precision. When the sample size is n = 5, 10, or 20, the average uncertainties of σαI and σαA correspond, respectively, to approximately 30%, 20%, and 15%. Giving an accurate and comparable assessment for σαI and σαA necessitates the reporting of intensity (in units of electrons), bandwidth, Δx, and the sample size. [ABSTRACT FROM AUTHOR]

Abstract Water temperature is key to the study of aquatic ectotherm ecology, but precise measurements of individual‐based thermal experience remain difficult to validate. The stable isotope composition of oxygen in biominerals acts as a natural thermometer due to the temperature dependence of isotopic fractionation between water and mineral phases. Coefficients of published temperature‐dependent fractionation equations, however, vary among taxa (the so‐called ‘vital effect’) without apparent consistent predictors, implying that species‐specific experimental validation may be needed before inferring temperature from biomineral oxygen isotope thermometry. Here, we describe a meta‐analysis conducted to assess the influence of biological and experimental sources of variation on the coefficients of published isotope thermometry equations. We observed that the thermal sensitivity (equation slope) was resistant to any biological or experimental factors, while the isotopic spacing between water and biomineral (equation intercept) showed consistent variation. Experimental conditions and phylogeny were the two main sources of variation in equation coefficients, where experiment approaches influenced both equation intercepts and the fit of the linear regression. Our results suggest that the use of common equation slopes and generalized taxa‐specific equation intercepts may be appropriate under some circumstances. We additionally suggest that processes related to oxygen balance and osmoregulation may influence equation intercepts, and suggest further experimental work in this area. Finally, our observations provide ground for improvement for future design and reporting of biomineral thermometry experiments.

Carbon and nitrogen composition and isotopic ratios (δ15N, δ13C, and δ13C-DIC) as well as physicochemical parameters were measured in hazardous waste leachate connected to an environmental pollution crime. A forensic metrology approach was employed by estimating the measurement uncertainty, including that from the sampling process, using range statistics. The physicochemical parameters demonstrated differences in the leachate from some of the different ponds and this was supported by carbon and nitrogen elemental and isotopic analyses. The isotopic signature of δ15N and δ13C-DIC was highly enriched in the heavy isotope demonstrating that those analyses are a substantial tool for leachate pollution tracking. The uncertainty of the measurements was below or slightly above 20% for most parameters which can be considered fit-for-purpose for a great deal of environmental surveys and was remarkably lower in the isotopic analyses. The uncertainty of measurement including the primary sampling is a relevant information in environmental investigations, especially forensic ones. This knowledge is crucial for a consistent interpretation of environmental samples analyses results, specially from polluted sites and pollution source characterization and tracking, where there is often substantial heterogeneity in environmental samples. [ABSTRACT FROM AUTHOR]

Copyright of Methods in Ecology & Evolution is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

backgroundThe lead isotope ratios (LIR) differ among different sourced samples. Previous domestic and oversea studies on source tracing by LIR in human blood or urine mainly focused on the comparison of blood or urine samples from the same or different individuals, while few comparisons between biological and environmental samples, and the reported relative standard deviations (RSDs) of the main LIR (207/206Pb and 208/206Pb) fluctuate widely from 0.3% to 1%. ObjectiveTo optimize inductively coupled plasma mass spectrometry (ICP-MS), obtain a better RSD, and determine LIRs of human blood, urine, and related environmental samples. MethodsThe ICP-MS was optimized for operating conditions and parameters according to the sensitivity and RSD of LIR. The study subjects were 40 lead-exposed workers in a lead-acid battery factory and 2 lead poisoned children in a hospital. The samples included 40 blood and 40 urine samples from the workers before shift, 4 dust samples and 2 water samples in the workplace on the same day before shift, 2 blood and 3 urine samples from the children before hospital admission due to lead-poisoning, and 4 urine samples after medical treatment. After heating and acid digestion, the LIR (207/206Pb and 208/206Pb) of biological and environmental samples were determined by the optimized ICP-MS method. t-test and two-dimensional traceability graphics were adopted to analyze the detection results. ResultsThe calibrated RSDs of the LIR (207/206Pb and 208/206Pb) of lead isotope standard solution were 0.11% and 0.08% respectively, and the NIST-SRM-981 actual values were 0.91531±0.00097 and 2.1670±0.0017, respectively. When the total concentration of lead was greater than 5 μg·L−1, the RSD of each isotope ratio was stable gradually; when the total concentration of lead was between 10-80 μg·L−1, the RSD was below 0.20%. There were statistically significant differences in the blood and urine LIR (207/206Pb and 208/206Pb) of the lead-exposed workers (t=5.831, P

Copyright of Geology & Exploration is the property of Geology & Exploration Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aims: Forests with various mixed patterns often show large differences in water use strategies. However, mixed planting may enhance the drought resistance of the whole forest community. We evaluated whether mixed planting could enhance the drought resistance of Robinia pseudoacacia and Quercus acutissima under different seasons in the warm temperate zone of North China. Methods: Shallow-rooted R. pseudoacacia and deep-rooted Q. acutissima were studied to determine plant water use strategies under different seasons and planting methods. We measured hydrogen and oxygen isotope ratios of two species grown under pure and mixed planting methods, as well as those of the environment, including rainwater, soil water, and groundwater in spring, summer, and autumn. Results: Hydrogen and oxygen isotopic contents of soil water were significantly less than groundwater and significantly more than rainwater irrespective of the season. However, season was the key factor influencing the plant water use strategies. In spring and autumn, Q. acutissima used more groundwater while R. pseudoacacia used more soil water; in summer, both of the two species took more use of rainwater and soil water. Mixed planting significantly increased the proportion of groundwater use and the diversity of plant water use strategies of two species. Conclusion: Diversity of plant water use strategies facilitate the coexistence of two species with the same ecosystem irrespective of the changes in water availability in their respective root zones. Besides, mixed planting can enhance the drought resistance of the whole forest community via reducing competition for the seasonal changes in water resources. [ABSTRACT FROM AUTHOR]

The determination of isotope ratios in individual uranium particles is very important for nuclear safeguards. In this work, accelerator mass spectrometry (AMS), thermal ionization mass spectrometry (TIMS), and secondary ion mass spectrometry (SIMS) were applied to isotope ratio analysis of individual uranium particles and compared in terms of background, measurement accuracy, and efficiency. Several individual uranium particles (1–7 μm) from certified reference materials were used as samples. The results show that the average values of blank counting rate of 235U for AMS, FT‐TIMS (FT: fission track), SEM‐TIMS (SEM: scanning electron microscope), and SIMS were 7.3, 7.8, 2.7 and 2.2 cps, respectively. The relative error of 234U/235U and 234U/236U isotope ratios of the particles from U200 for AMS were within 10% and 20%, whereas the results of FT‐TIMS and SIMS were within 5% and 10%, respectively. The relative error and external precision of 234U/238U and 235U/238U of the particles from U850 for the method of AMS, SEM‐TIMS, and SIMS were within 10% and 5%, respectively. For 236U/238U, the average values of the relative error and external precision measured by AMS were within 5%, which measured by SEM‐TIMS and SIMS were all within 10%. AMS has advantages in measuring 236U/238U. The measurement time of AMS and SEM‐TIMS was shorter than that of FT‐TIMS and longer than that of SIMS. It is considered that AMS and SEM‐TIMS have a certain development prospect, and it is necessary to research deeply. [ABSTRACT FROM AUTHOR]

While much about Alfvén eigenmode (AE) stability has been explored in previous and current tokamaks, open questions remain for future burning plasma experiments, especially regarding exact stability threshold conditions and related isotope effects; the latter, of course, requiring good knowledge of the plasma ion composition. In the JET tokamak, eight in-vessel antennas actively excite stable AEs, from which their frequencies, toroidal mode numbers, and net damping rates are assessed. The effective ion mass can also be inferred using measurements of the plasma density and magnetic geometry. Thousands of AE stability measurements have been collected by the Alfvén Eigenmode Active Diagnostic in hundreds of JET plasmas during the recent Hydrogen, Deuterium, Tritium, DT, and Helium-4 campaigns. In this novel AE stability database, spanning all four main ion species, damping is observed to decrease with increasing Hydrogenic mass, but increase for Helium, a trend consistent with radiative damping as the dominant damping mechanism. These data are important for confident predictions of AE stability in both non-nuclear (H/He) and nuclear (D/T) operations in future devices. In particular, if radiative damping plays a significant role in overall stability, some AEs could be more easily destabilized in D/T plasmas than their H/He reference pulses, even before considering fast ion and alpha particle drive. Active MHD spectroscopy is also employed on select HD, HT, and DT plasmas to infer the effective ion mass, thereby closing the loop on isotope analysis and demonstrating a complementary method to typical diagnosis of the isotope ratio.

Forests in Latvia are crucial, covering over half of the country’s territory and expanding continuously through afforestation and natural growth [...]

Stable hydrogen, carbon, nitrogen, oxygen and sulfur (HCNOS) isotope compositions expressed as isotope-delta values are typically reported relative to international standards such as Vienna Standard Mean Ocean Water (VSMOW), Vienna Peedee belemnite (VPDB) or Vienna Cañon Diablo Troilite (VCDT). These international standards are chosen by convention and the calibration methods used to realise them in practice undergo occasional changes. To ensure longevity and reusability of published data, a comprehensive description of (1) analytical procedure, (2) traceability, (3) data processing, and (4) uncertainty evaluation is required. Following earlier International Union of Pure and Applied Chemistry documents on terminology and notations, this paper proposes minimum requirements for publishing HCNOS stable-isotope delta results. Each of the requirements are presented with illustrative examples. [ABSTRACT FROM AUTHOR]

We measured Raman spectra of N2 fluids obtained at 0.1–25 MPa at room temperature. The 14N15N peak in the Raman spectrum of a low‐pressure N2 fluid is difficult to detect because of the prevalence of a group of peaks attributed to rotational vibration of 14N2. The Raman peaks of 14N15N and 14N2 of N2 fluid at 25 MPa were acquired at various exposure times. The mean values and standard deviations of the peak height ratios and peak area ones of 14N15N and 14N2 were examined for each time. The standard deviations of the peak height ratios and peak area ones were 2.2% and 1.9%, respectively, for 20 spectra acquired with peak height of 1 million counts of 14N2. The uncertainties are about two times higher than those predicted from the noise of a CCD. Improvement of the pixel resolution can enhance the precision of the nitrogen isotope ratios by Raman spectroscopy. [ABSTRACT FROM AUTHOR]

Serving as a medium between source water and cellulose, leaf water contributes to the isotope ratios (δ18O, δ2H) of plant organic matter, which can be used for paleoclimate reconstruction. This study is the first to examine the diurnal variations in the δ18O and δ2H of leaf water on the southern Tibetan Plateau. The δ18O and δ2H of leaf water were relatively low when precipitation events occurred. In particular, 18O and 2H of leaf water became extremely depleted 5 h after the precipitation event. Our findings demonstrate that precipitation can modify the isotope ratios of leaf water from external and internal causes. First, precipitation events affect meteorological elements, lead to decreases in leaf transpiration, and immediately weaken the isotope enrichment of leaf water ('rapid effect' of precipitation). Second, precipitation events affect the internal plant–soil water cycle process, causing the plant to preferentially use deeper soil water, and the corresponding isotope ratios of leaf water exhibit extremely low values 5 h after precipitation events ('delay effect' of precipitation). This study suggests that researchers need to be cautious in separating the signals of precipitation and hydrological processes when interpreting isotope records preserved in tree-ring cellulose archives from the Tibetan Plateau. [ABSTRACT FROM AUTHOR]

Hair samples, as a non-invasive biological material, it is gradually gaining attention in the fields of nuclear forensics, environmental monitoring, occupational exposure detection, and medicine due to its certain accumulation effect on human trace elements. At present, in the field of hair analysis, most of the existing researches use the bulk analysis technology to measure the average content of elements in hair, while there are few researches on hair micro-area analysis. In order to expand the application of hair analysis methods, the rat hair samples with high uranium content were obtained by feeding rats with uranyl nitrate solution. The pretreatment method of hair samples and the measurement method of uranium in hair by secondary ion mass spectrometer (SIMS) were studied. The results show that when measuring hair samples using SIMS, the grooves on the surface of the sample target can effectively improve the signal strength stability; coating copper on the sample surface can effectively reduce the surface charge accumulation and reduce the interference of polyatomic ion signal to uranium ion signal. The distribution, average content and isotope ratio of uranium in rat hair were measured by multi collected inductively coupled plasma mass spectrometry (MC-ICP-MS) and SIMS. The results show that this method can effectively judge whether rats drink uranium solution or not, and distinguish the type of uranium taken by rats. This study provides technical support for traceability analysis of hair samples, which is of great significance for the analysis of trace elements in hair.

Long-range transported atmospheric pollutants (or transboundary pollutants) include trace metals with isotope ratios and compositions that vary from those of domestic pollutants, which threaten mountain ecosystems. These differences can be applied as indices to evaluate the influence of transboundary pollutants on mountain ecosystems. Mosses play important ecological functions in mountains and are sensitive to atmospheric deposition. Therefore, using these indices for moss biomonitoring can provide a more accurate indication of ecosystem health. However, studies on indices that are appropriate for moss biomonitoring are limited. Here, the effectiveness of moss biomonitoring using trace metal indices was examined to evaluate transboundary pollutants in mountainous areas in Japan. Transboundary pollutants in these areas originate from mainland Asia and are characterized by high lead isotope ratios, lead-to-zinc (Pb/Zn) ratios, and arsenic-to-vanadium (As/V) ratios. Given that the abundance of transboundary pollutants decreases with distance from mainland Asia, these three indices are also expected to vary with distance. The Pb isotope ratios were found to decrease with distance from mainland Asia; in contrast, the Pb/Zn and As/V ratios did not display any notable relationship with distance. These results are likely attributed to biological and environmental factors that affect trace metal content in moss. Thus, moss Pb isotope ratios are useful indicators of transboundary pollutants in Japan's mountains, offering an important tool for comparable moss biomonitoring studies in East Asia. [ABSTRACT FROM AUTHOR]

This paper details the different steps for the isotopic determination of UAmO2 discs from analytical irradiation. MARIOS and DIAMINO irradiations were performed in materials testing reactors to study the behaviour of americium bearing blanket samples in regard of heterogeneous recycling in sodium-cooled fast reactor. Six irradiated discs were dissolved in hot cells and were analyzed to determine isotope ratios of uranium, plutonium, americium and neodymium. The ratios were measured combining chemical separations and TIMS analyses. Using the double isotope dilution methodology helps measuring 238Pu/238U, 241Am/238U and 148Nd/238U ratios with uncertainty about a few per mil (k = 2). [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ecology & Rural Environment is the property of Journal of Ecology & Rural Environment Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

For ensuring nuclear safeguards, we report the analytical signal-detection performance of thermal ionization mass spectrometry (TIMS) with continuous heating for the measurement of isotopic ratios in samples containing ultra-trace amounts of uranium. As methods for detecting uranium signals, peak-jumping mode using a single detector and static mode using multiple detectors were examined with U100 (10% 235U-enriched) uranium standard samples in the femtogram-to-picogram range. Uranium isotope ratios, n(235U)/n(238U), were measured down to levels of 1 fg and 3 fg in static and peak-jumping modes, respectively, while n(234U)/n(238U) and n(236U)/n(238U) values were measured down to levels of 100 fg in both modes. In addition, the dependency of the 238U signal intensity on sample quantity exhibited similar tendencies in both modes. The precisions of the isotope ratios obtained in the static mode over all sample ranges used in this study were overall slightly higher than those obtained in peak-jumping mode. These results indicate that isotope ratio measurements by TIMS with continuous heating are almost independent of the detection method, i.e., peak-jumping mode or static mode, which is characteristic of isotope-ratio measurements using the TIMS method with continuous heating. TIMS with continuous heating is advantageous as it exhibits the properties of multiple detectors within a single detector, and is expected to be used in various fields in addition to ensuring nuclear safeguards.

The most challenging problems in the field of chemico- and bioanalytical measurements are described. These problems are being solved, in particular, by participating in new international comparisons organized by the Consultative Committee for Amount of Substance: Metrology in Chemistry and Biology of the International Committee of Weights and Measures (CCQM CIPM). Solutions of these challenging problems are presented. The objectives and tasks of developing key comparisons in the following areas are described: isotopic measurements; determination of the purity of substances; organic analysis; bioanalytical measurements; measurements of aerosol particle parameters; measurements in the field of gas analysis and electrochemistry. It is shown that participation in international key comparisons allows obtaining valid and reliable results of measurements of the composition and properties of gas and liquid media, as well as solid substances and materials. [ABSTRACT FROM AUTHOR]

BACKGROUND: The use of PDO (protected designation of origin) and PGI (protected geographical indication) labels allows to protect and promote agricultural products characterized by unique features related to the place of origin and traditional know‐how. However, the presence of non‐authentic products in the market represents a fraud that can be tackled applying analytical techniques combined with chemometric analysis. In this study, we applied multi‐element and multi‐isotope analysis to characterize PDO and PGI apples cultivated in northern Italy, comparing them with Italian apples without labels of geographical indications. RESULTS: The multi‐element and multi‐isotope approach allowed to characterize the apples cultivated in northern Italy. Despite a significant effect of the sampling sites on the apple composition, the comparison of the multi‐chemical fingerprint of the apples significantly varied among cultivation areas. Results of this characterization were used to classify samples according to their cultivation area applying a linear discriminant analysis (LDA). Outputs of the LDA showed that correct sample classification can be successfully achieved (balanced accuracy > 96%). Moreover, using a selection of variables, it was possible to correctly classify samples also at regional level. CONCLUSION: The presented evidences indicate that the multi‐element and multi‐isotope fingerprint can be successfully applied to traceability studies. The combination of this characterization with chemometric tools allows the classification of Italian apples based on their origin both on a national and regional scale. This approach represents an interesting tool to enhance and protect PDO and PGI Italian products. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Field studies in post-mining sites on epigeic invertebrate groups are scarce despite their importance in pedogenesis and ecosystem multifunctionality. This research investigated the diversity, abundance and succession of aboveground invertebrates in a rehabilitated Pb/Zn tailings chronosequence of 5, 20 and 35 years. The study also explored the trophic relationship of selected arthropods and characterized the nitrogen (N) cycle using stable isotope measurements. The abundance and species richness in most investigated groups and the dominance index Berger–Parker (BP) of aboveground invertebrates increased with rehabilitation age from 0.17 BP in early to 0.31 BP in late stage. Elemental and stable isotope ratio analysis showed that N and C soil content increased and the C/N ratio decreased with age, yet despite this increased N availability in the system, the maturing N-cycle used N efficiently. The lack of large N losses from the system despite substantial atmospheric deposition inputs was indicated by the fact that N isotope ratios (δ15N) in plants and animals became significantly more negative with rehabilitation age, −6.0 δ15N for plants, −5.0 δ15N for herbivores and 3.0 δ15N for carnivores. The length of the invertebrate food chain expanded by more than half a trophic level (2.7‰ δ15N) for top predator Coleoptera from early to late stage, probably reflecting more complex food webs including intra-guild predation in older communities. In conclusion, δ15N measurements in plants and animals provided novel insights into the N-cycle, accumulative N flows and the trophic position in post-mining sites. It is proposed that isotope ratio measurements could be used as easy-to-measure, integrating indicators of nutrient cycling and the soil food web complexity of rehabilitated mine tailings and similar soil ecosystems. [ABSTRACT FROM AUTHOR]

This study presents a method for calibrating the isotope ratios of the total carbon, nitrogen, and sulfur in particulate matter (PM) collected from the Seoul metro using an elemental analyzer-isotope ratio mass spectrometer (EA-IRMS). Mixtures of isotope reference materials (MRMs) from the U.S. Geological Survey (USGS) and International Atomic Energy Agency (IAEA) reference materials formed an input dataset for generalized least squares (GLS) regression to yield calibration lines. The analytical method proposed in this study enabled the measurement of stable isotope ratios of total carbon, nitrogen, and sulfur simultaneously. Results showed good linearity and repeatability for carbon and nitrogen isotopes, but poor results for sulfur isotopes due to peak broadening. Reference values with uncertainties for the isotope ratios of total carbon, nitrogen, and sulfur were determined for the collected PM, demonstrating twice as much uncertainty as that of the USGS and IAEA reference materials. Homogeneity was the biggest uncertainty source for the calibrated values. Isotope ratios in PM's C/N/S were simultaneously calibrated with mixtures of IAEA and USGS reference materials using EA-IRMS. Calibration uncertainty was assessed using the generalized least squares. Homogeneity was also assessed. Parametric uncertainty evaluation was cross-validated by Monte Carlo simulation. [Display omitted] • Analytical method for isotope ratios of total C/N/S in the particulate matter were optimized for simultaneous measurement using EA-IRMS. • Isotope ratio values of the total C/N/S of the PM sampled in the Seoul metro were calibrated by mixtures of USGS and IAEA reference materials. • Calibration uncertainty were evaluted with those of measurement, regression, reference materials, and homegeneity. [ABSTRACT FROM AUTHOR]

The objective of this study is to determine the Pb concentration and 206Pb/204Pb, 206Pb/207Pb, 206Pb/208Pb from several Romanian winemaking regions, in order to highlight credible geographical markers of wine origin. The Pb level concentration and the ratios of 206Pb/204Pb, 206Pb/207Pb, 206Pb/208Pb were determined in 25 white and 9 red wines using ICP-MS techniques. Based on 206Pb/207Pb isotope ratios it can be concluded that the vines grown in the Tîrnave vineyard [Blaj (1.1790 average value)], Huși vineyard [Huși (1.1958 average value wine center), Averești (1.1908 average value)] and Iași vineyard [Copou (1.1875 average value) wine center], show traces of atmospheric pollution with lead [if 206Pb/207Pb=~1.1700-1.2200 (atmospheric pollution)]. Combining the 206Pb/204Pb with 206Pb/208Pb isotopic ratio may carry out a separation on the vineyards and wine-growing centers. Based on 206Pb/204Pb, 206Pb/207Pb and 208Pb/206Pb a separation of the wine samples was possible.

Endotoxemia induced in vivo in mice by intraperitoneal injection of lipopolysaccharide (LPS) leads to (neuro)inflammation and sepsis. Also the homeostasis of mineral elements can be altered through mechanisms that still are poorly understood. The isotopic composition of Mg and the concentrations of the minor elements Ca, K, Mg, Na, P, and S were determined in biological fluids and tissues of young (14–28 weeks) and aged (40–65 weeks) LPS-injected mice and age-matched controls to reveal potential effects of the LPS-induced infection. Blood plasma of young and aged LPS-injected mice showed a heavy Mg isotopic composition, as well as elevated Mg and P concentrations, compared to matched controls. The plasma Mg isotopic composition was correlated with the P concentration in aged mice. Also the liver Mg isotopic composition was strongly affected in the young and aged LPS-injected mice, while for aged mice, an additional effect on the urine Mg isotopic composition was established. These observations were hypothetically associated with liver inflammation and/or hepatotoxicity, and reduced urinary Mg excretion, respectively. Also a regional endotoxin-induced difference was observed in the brain Mg isotopic composition for the aged mice only, and was attributed to potential disruption of the blood-brain barrier.

As one of the largest volume flavor ingredients, vanillin remains an attractive target for development of a cost-effective and sustainable process to manufacture. Presented here is newly available data on the production of vanillin via fermentation in an engineered strain of Saccharomyces cerevisiae grown on sucrose ex-sugarcane. The use of the C4 plant source of carbohydrate resulted in a δ13C mean stable isotope ratio of -14.43 ‰ (SD = 0.24) relative to the V-PDB standard and a δ2H mean stable isotope ratio of -122.8 ‰ (SD = 2.9) relative to the SMOW standard by IRMS. The abundance of 14C in the fermentation derived vanillin averaged 14.01 dpm/gC (SD = 0.09) by AMS measurement. These data are compared to historical data collected on vanillin derived from a number of sources to provide a more holistic view on vanillin bulk isotope data based on its method of manufacture.

When measuring the isotope ratio of plutonium by thermal ionization mass spectrometry with conventional method, the plutonium isotope standard material is usually needed to calibrate the bias caused by the isotope fractionation which is the main factor that influences the accuracy of results. Recent years, the total evaporation technique has become a good choice because of its inherent characteristics that can obtain results with no significant bias without calibrate by external standard. In this work, the main factors were investigated that influence the total evaporation measurement of thermalionization mass spectrometry, including the amplifier current gain calibration, sample amount, and the isobaric interference 238 U and 241 Am. 241 Am was separated from the aged plutonium by UTEVA resin, it was shown that isotopic analysis of plutonium should be completed within a reasonable time period after separation from Americium to minimize interference of 241 Am in-growth from decaying 241 Pu, and the interval limiting between sample purification and isotopic analysis was about 20 days to make sure the accuracy and precision, the re would be about 2% bias after 30 days of separation. The sample lost between integration due to the necessary to adjust the filament current and the residual sample after measuring was eliminated as less than 0. 3%. Measured with total evaporation technique utilizing Faraday cups only, IRMM-086 with different sample loadings were studied respectively, the results showed that sample loading between 50 and 100 ng were likely enough for good accuracy and precision, but there were also slightly biases in the 238 Pu/ 239 Pu and 242 Pu/239 Pu due to the low signal of 238 P u and 242 Pu influenced by the noise of Faraday cups. The results of IRMM-086 using total evaporation and conventional techniques were compared, and showed that the total evaporation technique could obtain better accuracies than t he conventional method while sample loading for total evaporation and conventional were 50 ng and ZOO ng respectively. There was no significant bias between measured and certified value when isotope ratio was more than 10-4 For IRMM-086, the relative standard deviations of 240 Pu/ 239 Pu, 241 P u/ 239 Pu, 242 Pu/239Pu measured by total evaporation were 0. 006 8%, 0. 50% and 0. 83%, respectively. Giving high precision and accuracy results without calibration, the total evaporation technique will be more widely used when we have a lower noise amplifier for Faraday collectors. In the field of spent fuel reprocessing analysis, plutonium isotope composition varies greatly due to different b urn-up. Total evaporation measurement technology has a very good application prospect in the field of plutonium isotope composition measurement. [ABSTRACT FROM AUTHOR]

This article explores the impact of an arginine phosphate-containing fertilizer on nitrogen uptake, carbon content, and elemental concentrations in pine needles in different forest types in Latvia. The study used isotope ratio mass spectrometry and inductively coupled plasma mass spectrometry to analyze pine needle samples. The findings reveal diverse patterns in nitrogen uptake and isotope ratio changes among the forest types, indicating the importance of considering forest type and environmental conditions when assessing fertilizer efficacy. This research contributes to our understanding of nutrient dynamics in forest ecosystems and guides sustainable forest management practices. [Extracted from the article]

Abstract All elements with two or more isotopes show natural variation in their isotopic composition as a result of the isotope fractionation that accompanies (bio)chemical reactions and (bio)physical processes. Multicollector inductively coupled plasma‐mass spectrometry (MC‐ICP‐MS) offers the precision required to reveal and quantify the differences in isotope ratios thus caused, although they are often of sub‐permil magnitude only. Using MC‐ICP‐MS, it has been shown that (a) in different body compartments, essential mineral elements may display different isotopic compositions, and (b) disease conditions may alter the isotopic composition of an essential mineral element in a biofluid and/or tissue. As a result, high‐precision isotopic analysis of these elements is a powerful way to unravel the actual role these essential mineral elements play in specific biochemical processes. Moreover, isotope ratio shifts also show promise as a diagnostic or prognostic tool. Despite the intensive sample pretreatment preceding MC‐ICP‐MS isotopic analysis and the high purchase and running costs of the instrumentation, this approach may be valuable, especially for diseases that can otherwise only be established at a later stage and/or via a more invasive approach. This review paper describes the basics of “biomedical isotopic analysis” and uses selected cases from the literature to sketch the state‐of‐art and illustrate in which context isotope ratio markers could be exploited in a clinical context.