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The gravimetric isotope mixture method is the primary method to determine absolute isotope ratios. This method, however, depends on the existence of suitable spike materials and knowledge of their purities. Determining the purity of the spikes can be tedious and labour-intensive. In this publication, an advancement of the gravimetric isotope mixture method, rendering the determination of the purity of the spike materials unnecessary, is presented. The advancement combines mass spectrometry and ion chromatography leading to an approach being independent of the purity of the spike materials. In the manuscript the mathematical background and the basic idea of the novel approach are described using a two-isotope system like copper or lithium. [ABSTRACT FROM AUTHOR]

A new accelerated oxidation-ion chromatography method has been proposed to determine the phosphorus content in biodiesel. The feasibility of the method was verified based on its linear correlation, detection limit, accuracy, and comparison with other methods. Further, the effects of interfering ions and accelerated oxidation time on the phosphorus content determination have been discussed. The results revealed a good linear correlation coefficient (r = 0.99996) over a PO43− concentration range of 0.1–4.0 mg·L−1. The limit of detection (LOD) and limit of quantification (LOQ) were found to be 0.005 and 0.016, mg·L−1, respectively. The intra-day accuracy (relative standard deviation (RSD), n = 5) ranged between 1.08–3.96%, while the inter-day accuracy (RSD, n = 15) was 1.66–6.67%, and the recovery rate was between 80.88% and 89.71%. The matrix elements in the biodiesel samples had no significant effect on the determination of phosphorus content. Under an oxidation temperature of 110 ℃ and ventilation rate of 10 L·h−1, the optimum accelerated oxidation time of biodiesel was found to be 18 h. Compared with other methods, the proposed method exhibited a better linear range and the lowest LOD. Furthermore, the efficacy of the method for quantifying the content of phosphorus in biodiesel has been validated through actual sample analysis. [ABSTRACT FROM AUTHOR]

Relative to suppressed conductometric anion exchange chromatography, conductometric ion exclusion chromatography (IEC) is much less popular. Poor limit of detection and manual preparation of eluent are primarily responsible for this. We describe an electrodialytic phosphoric eluent generator for the online production of phosphoric acid eluent at a concentration exceeding 35 mM. It is a sandwiched configuration consisting of three channels isolated by stacked anion exchange membranes and a bipolar membrane plus stacked anion exchange membrane. Such a unique configuration ensures the production of gas‐free eluent, obviating the need for a gas removal device. The resulting eluent concentration is controlled by varying the current. Coupled with an ultraviolet absorbance detector, a 0.04–16.67 mg/L limit of detection for model organic acids was achieved by IEC equipped with an electrodialytic phosphoric eluent generator. [ABSTRACT FROM AUTHOR]

Iodine and bromine play central roles in polar atmospheric chemistry: iodine influences the atmospheric oxidative capacity and can generate cloud condensation nuclei, while bromine participates in ozone depletion reactions, known as bromine explosions. Here we present a very sensitive analytical method for Br and I speciation by coupling the ion chromatography system (IC) with an inductively coupled plasma sector field mass spectrometer (ICP-SFMS). We achieved sub-picogram-per gram (pg g−1) as limits of detection (LODs) ranging from 0.4 pg g−1 for I−, 0.8 pg g−1 for IO3−, 4 pg g−1 for Br−, and 1 pg g−1 for BrO3−, respectively. These values represent a decrease of up to 30 times compared to the LODs reported in other studies. The method was validated using deep snow samples from the Svalbard Islands, collected at the end of the polar night to quantify various oxidized compounds during their seasonal minimum. In the future, this method could prove useful in the paleoclimatic study of ice cores and snow, as well as in ice chemistry research. [ABSTRACT FROM AUTHOR]

Heated tobacco products (HTPs) are newly developed nicotine delivery systems via the inhalation of mainstream aerosols generated during the heating of tobacco leaf materials. Previous studies have shown that the amount of chemicals generated is much lower than that generated by conventional combustible cigarettes. However, little attention has been paid to formate, a conjugated base of formic acid with potentially toxic effects on human health. This study aims to understand the actual emission levels and behaviour of formate in mainstream aerosols produced by commercially available HTP devices in Japan. Aerosols were generated from four types of devices with regular and menthol-type flavours using a vaping machine following the CRM 81 puffing protocol. Formate was tapped in 5 mM sodium carbonate solution and subsequently analysed using ion chromatography. The results showed that the total emission amount of formate ranged from 0.0027 ± 0.0031 to 0.27 ± 0.055 mg L−1, varying with heating temperature and flavour type. Moreover, the majority of formate existed in a particulate form due to the weak-basic property of the aerosol, and the formate emission level was much greater than the workplace exposure limit for the direct inhalation of mainstream aerosols. The formate in the mainstream aerosol can be considered a health concern, when using "high-temperature type" HTPs over a long period. [ABSTRACT FROM AUTHOR]

Epoxy resins, as important thermosetting polymers, exhibit excellent adhesion to various substrates. In view of this, reticulate coating of triglycidyl isocyanate with triethylenetetramine was introduced onto the surface of poly(styrene‐divinylbenzene) utilizing amine curing reaction to obtain poly(styrene‐divinylbenzene)@triglycidyl isocyanate‐triethylenetetramine composite microspheres. The amino groups and epoxy groups of triglycidyl isocyanate‐triethylenetetramine endowed poly(styrene‐divinylbenzene) with good reactivity, which could be quaternized under mild conditions to obtain an anion exchange chromatographic stationary phase. The quaternized poly(styrene‐divinylbenzene)@triglycidyl isocyanate‐triethylenetetramine was characterized by scanning electron microscope, Fourier‐transform infrared spectroscopy, N2 adsorption‐desorption experiment, et al. The chromatographic performance of the customized column was evaluated by separating seven conventional anions, organic weak acids, and carbohydrates. Poly(styrene‐divinylbenzene)@triglycidyl isocyanate‐triethylenetetramine possesses the uniform size of poly(styrene‐divinylbenzene) microspheres and good reactivity of triglycidyl isocyanate‐triethylenetetramine, which offers a flexible strategy for the preparation of anion exchange stationary phase. The column exhibits excellent chemical and mechanical stability and chromatographic performance. Finally, the column was successfully applied for the determination of nitrite in pickles. [ABSTRACT FROM AUTHOR]

The aim of this work was to the obtaining novel mixed-mode stationary phases with increased hydrophilicity and applying them in ion and hydrophilic interaction liquid chromatography. The resins were obtained by the sequential covalent attachment of branched polyethylenimine and polyelectrolytes synthesized from diepoxide and a secondary amine on the surface of epoxidized polystyrene–divinylbenzene. To increase the shielding degree of the polymer substrate, an additional polymerization of glycidol was carried out in the functional layer of the sorbent at an increased pH of the reaction medium. The synthesized phases possessed increased hydrophilicity compared to most resins based on a styrene–divinylbenzene copolymer with covalently attached layers. This was evidenced in the ion chromatography mode by a decrease in the relative retention of polarizable anions, weakly hydrated oxyhalides (up to a change in the elution order of the bromate), and haloacetic acids. In the hydrophilic interaction liquid chromatography mode, an increased hydrophilicity of the phases was confirmed by an increase in the retention factors of polar analytes, as well as by the reversal of the elution order of ascorbic and nicotinic acids as compared to the phases based on polystyrene–divinylbenzene presented in the literature. The low efficiency of the obtained stationary phases in the ion chromatography mode was noted, which is associated with slow mass transfer in the bulk polymer functional layer. The negative impact of the polymer layer on efficiency in hydrophilic interaction liquid chromatography is less pronounced due to the presumably smaller thickness of the part of the functional layer involved in this mode. The proposed method for the synthesis of resins ensures an increase in the efficiency, selectivity, and separation ability of sorbents in the hydrophilic interaction liquid chromatography mode as compared to phases based on a styrene–divinylbenzene copolymer described previously in the literature. The resulting highly hydrophilic resins makes it possible to separate a mixture of 9 nitrogenous bases and nucleosides in 18 min, 6 vitamins in 24 min, and 8 sugars in 11 min. Thus, the method of substrate hydrophilization proposed in this work is promising for improving the chromatographic characteristics of phases in the hydrophilic interaction liquid chromatography mode and can be used to create sorbents with increased selectivity and efficiency. [ABSTRACT FROM AUTHOR]

This study investigates the potential health risks associated with ion concentrations in fountains used for drinking water in the Antalya/Konyaaltı tourism center region. A total of 32 fountain samples commonly used during the summer were analyzed to determine the anion and cation concentrations using ion chromatography equipped with a conductivity detector. The results showed high accuracy and reliability, with R2 values ranging between 0.998 and 0.999 and recovery values between 97% and 110% at low and high concentrations. The method detection limit and method quantification limit were determined as 0.004 and 0.276, respectively, whereas the pH values ranged from 6.71 to 7.69. When examining the average fluoride and nitrate levels in different age groups, the nitrate daily acceptable intake (total hardness index) values were found to be 0.175, 0.091, and 0.076 µg kg−1 body weight per day for children, adolescents, and adults, respectively. Overall, the study suggests that children have the highest exposure levels due to their lower body weight, and exposure levels decrease with increasing age. [ABSTRACT FROM AUTHOR]

The potential of utilizing inorganic constituents in processed animal proteins (PAPs) for species identification in animal feeds was investigated, with the aim of using these constituents to ensure the quality and authenticity of the products. This study aimed to quantify the inorganic content across various PAP species and assess whether inorganic analysis could effectively differentiate between PAP species, ultimately aiding in the identification of PAP fractions in animal feeds. Four types of PAPs, namely bovine, swine, poultry, and fish-based, were analyzed and compared to others made up of feathers of vegetal-based feed. Also, three insect-based PAPs (Cricket, Silkworm, Flour Moth) were considered in this study to evaluate the differences in terms of the nutrients present in this type of feed. Ionic chromatography (IC) was used to reveal the concentrations of NO3−, NO2, Cl−, and SO42−, and inductively coupled plasma optical emission spectroscopy (ICP-OES) to detect Al, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, P, Si, Sr, Ti, and Zn. The application of multivariate chemometric techniques to the experimental results allowed us to determine the identification capability of the inorganic composition to identify correlations among the variables and to reveal similarities and differences among the different species. The results show the possibility of using this component for discriminating between different PAPS; in particular, fish PAPs are high in Cd, Sr, Na, and Mg content; swine PAPs have lower metal content due to high fat; feathers and vegetal feed have similar Al, Si, and Ni, but feathers are higher in Fe and Zn; and insect PATs have nutrient levels comparable to PAPs of other origins but are very high in Zn, Cu, and K. [ABSTRACT FROM AUTHOR]

Residues of various highly polar pesticides and their metabolites are commonly found in numerous food products. Some of these compounds, such as glyphosate, are not only used in large amounts in agriculture, but are also controversially discussed in public. Here, we present a method, employing ion chromatography (IC) coupled to tandem mass spectrometry (IC-MS/MS), for the analyses of glyphosate, aminomethyl phosphonic acid (AMPA), N-acetyl-glyphosate (NAGly), fosetyl, and 10 further highly polar pesticides and metabolites in various plant and animal matrices following a minimal sample preparation by means of the QuPPe method. Thorough investigations showed that an AS19 column enabled the analysis of all 14 compounds within 30 min. The best sensitivity could be obtained with the make-up solvent acetonitrile being admixed to the mobile phase at a 1:2 flow rate ratio. Matrix effects were thoroughly studied in terms of ion suppression and retention time shifts. Conductivity detection was used to monitor elution profiles of matrix co-extractives in comparison with matrix effect profiles obtained by continuous post-column infusion of a mix with 13 highly polar pesticides and metabolites. These tests indicated that a fivefold dilution of QuPPe extracts was suitable for the routine analysis of samples for MRL-conformity, as it considerably reduced matrix effects maintaining sufficient sensitivity and high recovery rates in eight different commodities. The suitability of the final method for its application in routine analysis was verified by the analysis of >130 samples containing incurred residues where the results were compared with two existing LC-MS/MS methods. [ABSTRACT FROM AUTHOR]

Objective To establish a method for the quantitative analysis of iodine and its compounds in workplace air by ion chromatography pulsed amperometric detector. Methods Air samples were collected using alkaline -activated carbon solid -phase extraction tubes and eluted with 10 mL of the 20 mmol/L sodium bicarbonate solution for 30 minutes. The eluate was separated using the Dionex ICS -5000 ion chromatography system with the Dionex IonPac AS11 -HC high - performance anion separation column and detected by the pulsed amperometric detector, with the retention time for qualitative analysis and the peak area for quantitative analysis. Results The method had a correlation coefficient of 0.999 7 for the standard curve, a detection limit of 0.519 μg/L (25 μL injection volume), and a minimum quantifiable mass concentration of 2.3 μg/m³ calculated using a sampling volume of 7.5 L. The method had good reproducibility, with relative standard deviations ranging from 2.72% to 4.10% and an internal recovery rate of 95.8% to 98.0% for simulated samples. The average elution efficiency of alkaline-activated carbon solid-phase extraction tubes was more than (94.1% ± 2.65% ). Iodine and its compounds could be stably stored for 5 days at 4 ℃ . Conclusions The quantitative analysis method of the ion chromatography pulsed amperometric detector was fast, convenient, efficient, and accurate. It is satisfied with the requirement for the determination of iodine and its compounds in workplaces [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department 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.)

Abstract Iodine and bromine play central roles in polar atmospheric chemistry: iodine influences the atmospheric oxidative capacity and can generate cloud condensation nuclei, while bromine participates in ozone depletion reactions, known as bromine explosions. Here we present a very sensitive analytical method for Br and I speciation by coupling the ion chromatography system (IC) with an inductively coupled plasma sector field mass spectrometer (ICP-SFMS). We achieved sub-picogram-per gram (pg g−1) as limits of detection (LODs) ranging from 0.4 pg g−1 for I−, 0.8 pg g−1 for IO3 −, 4 pg g−1 for Br−, and 1 pg g−1 for BrO3 −, respectively. These values represent a decrease of up to 30 times compared to the LODs reported in other studies. The method was validated using deep snow samples from the Svalbard Islands, collected at the end of the polar night to quantify various oxidized compounds during their seasonal minimum. In the future, this method could prove useful in the paleoclimatic study of ice cores and snow, as well as in ice chemistry research.

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group 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.)

Ion chromatography and related techniques have been the most popular separation methods used in the determination of organic and inorganic anions and cations, predominantly in water and wastewater samples. Making progress in their development and introducing new stationary phases, methods of detection and preparation of samples for analyses have given rise to the broadening of their analytical range. Nowadays, they are also used for substances that are not ionic by nature but can convert to such forms under certain conditions. These encompass, among others, carbohydrates, whose role and significance in humans' lives and environment is invaluable. Their presence in the air is mostly due to the industrial burning of biomass for energy production purposes. In addition, the content of sugars in plants, fruits and vegetables, constituting the base of human diets, affects our health condition. Given that, there is not only a need for their determination by means of routine methods but also for searching for novel analytical solutions. Based on literature data from the past decade, this paper presents the possibilities and examples of applications regarding ion chromatography and related techniques for the determination of carbohydrates in environmental samples, biomass and plants constituting food or raw materials for food production. Attention has been paid to the virtues and limitations of the discussed separation methods in this respect. Moreover, perspectives on their development have been defined. [ABSTRACT FROM AUTHOR]

This research aims to validate the use of ion chromatography to determine fluoride anions. Determining the fluoride anion content in water is crucial to ensure its quality. Ion chromatography has proven to be efficient in this analysis, adhering to the APHA 4110B-2017 standard. Before being routinely used, the method must be verified to ensure adequate linearity, precision, accuracy, and detection limits. Testing shows a high correlation value (0.9986), with a detection limit (LoD) of 0.0034 mg/L and a quantification limit (LoQ) of 0.1132 mg/L. Precision (%RSD) is 1.02%, while accuracy (recovery) reaches 105%. Linearity analysis indicates F-calculated < F-table (1.42 < 3.18), validating the method for determining fluoride levels in water through ion chromatography. [ABSTRACT FROM AUTHOR]

This study aimed to develop and optimize an ion chromatography methodology for the determination of inulin in aqueous extracts of roasted açaí (Euterpe oleracea Mart.) seeds belonging to the Arecaceae family. Additionally, the optimization of inulin extraction conditions was sought using an experimental design with temperature and solid-to-solvent ratio as independent variables. Ion chromatography analysis was adjusted by varying flow conditions, eluent composition, and column oven temperature. The optimized chromatographic conditions were as follows: a flow rate of 1 mL min−1, eluent containing 2 mmol L−1 NaOH and 5 mmol L−1 sodium acetate in an isocratic mode, column oven temperature of 20 °C, injection volume of 20 µL, and a runtime of 40 min. The optimal extraction condition was determined using a temperature of 94.1 °C and a solid-to-solvent ratio of 10/135.25 (g mL−1), resulting in an inulin content of 16% (w w−1). The developed methodology met the criteria and guidelines of the Association of Official Analytical Chemists (AOAC) validation guide, including linearity, precision, accuracy, repeatability, reproducibility, matrix effect, and recovery. The results demonstrate the efficiency and applicability of the methodology, which is essential for identifying the best ways to utilize açaí seeds in an environmentally responsible and economically viable manner. This study promotes innovation and sustainable development in the Amazon region, aligning with the principles of the green concept. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group 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.)

Hydrothermal carbonization (HTC) is a promising technology for wet manure treatment by converting animal manure into valuable fuels, materials, and chemicals. Among other HTC process parameters, the temperature influences HTC products the most. As various animal manures have different compositions, it is not certain how the HTC temperature influences the hydrochar and HTC process liquid. To evaluate the temperature's effect on HTC, three different manures (poultry, swine, and dairy) were hydrothermally carbonized at three different temperatures (180, 220, and 260 °C), and solid and liquid products were characterized for their morphology, elemental compositions, and ions. The carbon contents of the hydrochar reached as high as 38.98 ± 0.36% and 40.05 ± 0.57% for poultry and swine manure, respectively, when these manures were treated at 260 °C. Ammonium showed an around 30% increase in poultry manure hydrochar with the increase in the HTC temperature. In contrast, in swine manure, it decreased by around 80%, and in dairy manure, the HTC temperature did not have any remarkable effect on the ammonium content. The process liquids from HTC of dairy manure at 220 °C showed the most balanced distribution of different ions, with 4970 ± 673 ppm of sodium, 4354 ± 437 ppm of ammonium, 2766 ± 417 ppm of potassium, 978 ± 82 ppm of magnesium, 953 ± 143 ppm of calcium, 3607 ± 16 ppm of chloride, and 39 ± 7 ppm of phosphate. These results emphasize the manure-specific effects of the HTC temperature on both solid and liquid products, indicating the need for optimized strategies to enhance HTC processes for various types of animal manures. [ABSTRACT FROM AUTHOR]

Continuous Li monitoring is vital in ensuring the safety and treatment efficacy of probationers with psychotic disorders, such as bipolar disorder, depression, and mania. This study introduced a validated quantitative analysis method using ion chromatography (IC) to monitor Li+ concentration in urine. The methodology involved centrifuging the urine sample, diluting the supernatant with deionized water, and subsequent IC analysis using guard and analytical columns for precise Li+ concentration measurement. The method quantified Li+ within the range of 2–400 ng/mL, demonstrating its excellent linearity (r2 = 0.9983) with a weighting factor of 1/x. Precision levels below 12.8% were observed for both intraday and interday measurements with an accuracy of −5.9% to 15.2%. The detection limit was identified as 0.12 ng/mL. The method conformed to analytical standards in terms of selectivity, matrix effect, process efficiency, dilution integrity, and stability. Moreover, the method distinctly quantified Li+ while effectively eliminating interference from Na+, which had a similar retention time as Li+ with higher concentrations. Further, the developed method was successfully applied to analyze forensic urine samples of Li users, demonstrating its applicability for medication compliance monitoring using urine samples of mentally disordered probationers. [ABSTRACT FROM AUTHOR]

Copyright of Urban Geology is the property of Urban Geology 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.)

Determinations of three nutrients (nitrate, nitrite and phosphate ions) in seawater were investigated by continuous flow analysis (CFA) based on colorimetry and ion chromatography (IC). The accuracies of those methods were examined by discussing their uncertainties. Although some of the nitrite and phosphate validations were not sufficient due to low concentrations, the results of nitrate agreed well with each other. While CFA is popular in this field, its comparison with IC was reported for the first time and contributed to an increase in the reliability of the analytical results. Finally, the investigation led to the development of three kinds of seawater certified reference materials (CRMs) of the National Metrology Institute of Japan (NMIJ) (NMIJ CRM 7601-a, 7602-a and 7603-a) for which the property values of nutrients including dissolved silica were given. The details of the development are described in the present paper. [ABSTRACT FROM AUTHOR]

Antarctic seaweeds are vital components of polar marine ecosystems, playing a crucial role in nutrient cycling and supporting diverse life forms. The sulfur content in these organisms is particularly interesting due to its implication in biogeochemical processes and potential impacts on local and global environmental systems. In this study, we present a comprehensive characterization of seaweed collected in the Antarctic in terms of their total sulfur content and its distribution among different classes of species, including thiols, using various methods and high-sensitivity techniques. The data presented in this paper are unprecedented in the scientific literature. These methods allowed for the determination of total sulfur content and the distribution of sulfur compounds in different fractions, such as water-soluble and proteins, as well as the speciation of sulfur compounds in these fractions, providing valuable insights into the chemical composition of these unique marine organisms. Our results revealed that the total sulfur concentration in Antarctic seaweeds varied widely across different species, ranging from 5.5 to 56 g kg−1 dry weight. Furthermore, our investigation into the sulfur speciation revealed the presence of various sulfur compounds, including sulfate, and some thiols, which were quantified in all ten seaweed species evaluated. The concentration of these individual sulfur species also displayed considerable variability among the studied seaweeds. This study provides the first in-depth examination of total sulfur content and sulfur speciation in brown and red Antarctic seaweeds. [ABSTRACT FROM AUTHOR]

Potassium salt is one of the scarcest mineral resources in China, and it is the main raw material for potassium fertilizer in the three major fertilizers of agriculture. Currently, soluble potassium salt resources are the main ones with development and utilization value. At present, there is no national standard material or standard analysis method for soluble potassium salts. In the experiments, soluble potassium salt samples were dissolved by electric heating plate and ultrasonic oscillation. According to the main components of soluble potassium salts, a method for the determination of K+, Na+, Ca2+ and Mg2+ by ICP-OES and a method for the determination of Cl− and SO42− by ion chromatography (IC) in soluble potassium salts were established. Through experimental conditions, the dissolution temperature of the electric heating plate was determined to be 160℃ and slightly boiled for 20min; the ultrasonic oscillation dissolution power was 60Hz and the time was 20min. The precision of the two methods was between 0.55%−3.19% (RSD, n=11), and the detection limit was between 0.01μg/g to 0.05μg/g. Both dissolution methods of soluble potassium salts can be widely used in daily detection. The electric heating plate dissolution method is more suitable for batch sample analysis in the laboratory. The ultrasonic oscillator dissolution method is simple and fast, and can be widely used in the field exploration of potassium salts, which can greatly improve the work efficiency and guide the smooth development of prospecting operations in real time. [ABSTRACT FROM AUTHOR]

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher 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.)

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group 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.)

Two methods for increasing the degree of hydrophilization and shielding of a resin substrate based on a styrene–divinylbenzene copolymer with attached polyethylenimine quaterinized with glycidol are proposed. The first method is the polymerization of glycidol in a functional layer by varying the pH of the reaction medium, and the second one is the modification of the substrate by oxidizing double bonds on its surface to form anchor epoxy groups. It is demonstrated that, in the first case, the optimal approach is to add glycidol twice before and after adding an alkali, because, in this case, the first addition of glycidol is consumed for the quaternization of the polyamine, and the second addition—for the polymerization in ion-exchange centers. The novel method of substrate modification in combination with the developed method for creating hydrophilic layers made it possible to significantly reduce the retention of oxohalides, haloacetic acids, and polarizable anions in the suppressed ion chromatography mode and amino acids in hydrophilic interaction liquid chromatography mode up to a change in the elution order. The obtained stationary phases are suitable for the simultaneous determination of standard inorganic anions, oxohalides, and haloacetic or alkylphosphonic acids in an ion chromatography mode, and also for the separation of amino acids, sugars, and vitamins in a hydrophilic interaction liquid chromatography mode. [ABSTRACT FROM AUTHOR]

In the restoration or rehabilitation of traditional buildings, compatible materials with known characteristics must be used. However, the existing literature lacks comprehensive studies on the characterisation of Persian mud–straw plaster, focusing primarily on Persian adobe. Moreover, previous research on Persian adobe has primarily employed XRF and XRD tests, neglecting ion chromatography, moisture sorption isotherm determination, and thermogravimetric analysis with differential scanning calorimetry. Consequently, there is a shortage of information regarding the elemental composition, mineralogical characteristics, moisture sorption behaviour, and thermal properties of Persian mud–straw plaster, as well as Persian adobe bricks. This paper aims to address this research gap by examining historical and new adobe bricks and mud–straw plaster used in Iran, utilising a comprehensive array of analytical techniques. The results from XRF analysis reveal relatively similar chemical compositions across all samples, while XRD analysis indicates predominantly similar mineral phases. Ion chromatography results demonstrate higher conductivity and chloride concentrations in the mud–straw samples than the adobe samples, with higher values for new samples than historical ones. Freshly used straw, clay, or soil may have higher chloride concentrations caused by the arid climate and soil salinisation in the area. Additionally, moisture sorption isotherm determination results show that adobe and mud–straw plaster with a higher salt load of chlorides have significantly higher moisture absorption. The increased straw quantity in the samples increases the moisture content. Furthermore, thermogravimetric analysis and differential scanning calorimetry indicate that, at low heating, adobe and mud–straw plaster lose water due to dehydration, and at high heating, they lose carbon dioxide due to decarboxylation. The comprehensive characterisation of Persian adobe and mud–straw plaster in this study fills a significant gap in the literature and offers invaluable insights for informing restoration and rehabilitation processes, ensuring the compatibility of the materials used. [ABSTRACT FROM AUTHOR]

In August 2021, the Mar Menor, a saltwater lagoon located in the Region of Murcia (Spain), suffered a tragic environmental episode of dystrophic crisis and anoxia. The appearance of numerous dead fish in different areas of the lagoon over the course of days put all the authorities and the population of the area on alert. This paper shows a case study of what happened in the lagoon in terms of the presence of the most common inorganic pollutants. Measurements of the concentration of nitrogen species, phosphates and main heavy metals were carried out at different sampling sites in the Mar Menor from May 2021 to November 2022. Chemical analyses were carried out for each of the species under study. These analyses provide valuable information about the dystrophic crisis caused by a classic eutrophication process that began with the excessive nutrient input into the Mar Menor. Ion chromatography and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) were used as instrumentation for the quantification of these samples. The species whose values were greatly increased after the tragic episode described above were nitrates. The concentration varied significantly at the different sampling sites throughout the study. On the last sampling date, decreased concentrations of all the species were measured at each of the sampling sites, coinciding with the apparent good state of the lagoon. [ABSTRACT FROM AUTHOR]

Selenite (SeO3 2−, Se (VI)) are the main forms of selenium existing in the aqueous media and acknowledged to upshot critical mutilation to well-being on surplus intake. Water is considered as one of the supreme itineraries for selenium inlet because of its adulteration with selenium via geogenic and anthropogenic practices. On the whole, Se (IV) is more noxious as compared to Se (VI); therefore, it is essential to develop remedial solution for their removal. The current work employs adsorption method and validates metal–organic framework based on iron, MIL-53 (MIL is fully known as Material of Institute Lavoisier), for selenium (IV) eradication from water. The Fe-MOFs are studied about influence of pH, preliminary selenite levels, time of contact, adsorbent dosage, etc., on the selenium removal efficacy. The selenium quantification is done with ion chromatography coupled with a conductivity detector. The study reveals that metal–organic framework based on iron could significantly remove selenite in aqueous conditions at an optimized pH 7 and a removal time of 4 h. Based on the higher correlation coefficient (R4 2−, Se (VI)) are the main forms of selenium existing in the aqueous media and acknowledged to upshot critical mutilation to well-being on surplus intake. Water is considered as one of the supreme itineraries for selenium inlet because of its adulteration with selenium via geogenic and anthropogenic practices. On the whole, Se (IV) is more noxious as compared to Se (VI); therefore, it is essential to develop remedial solution for their removal. The current work employs adsorption method and validates metal–organic framework based on iron, MIL-53 (MIL is fully known as Material of Institute Lavoisier), for selenium (IV) eradication from water. The Fe-MOFs are studied about influence of pH, preliminary selenite levels, time of contact, adsorbent dosage, etc., on the selenium removal efficacy. The selenium quantification is done with ion chromatography coupled with a conductivity detector. The study reveals that metal–organic framework based on iron could significantly remove selenite in aqueous conditions at an optimized pH 7 and a removal time of 4 h. Based on the higher correlation coefficient (R2 ) criterion, the selenite adsorption onto MIL-53 (Fe) is proposed to follow pseudo-second-order kinetics (R2=0.9655) and Langmuir adsorption (R2=0.9948) mechanism. Multiple regeneration and reuse experiments show that the MIL-53 (Fe) remained reusable with only 4% reduction in the adsorption efficiency after three cycles. The present finding thus presents a new media for selenite remediation from water. [ABSTRACT FROM AUTHOR]

Nitrogen oxides (NOX) in the atmosphere cause oxidation reactions with photochemical radicals and volatile organic compounds, leading to the accumulation of ozone (O3). NOX constitutes a significant portion of the NOy composition, with nitrous acid (HONO) and nitric acid (HNO3) following. HONO plays a crucial role in the reaction cycle of NOX and hydrogen oxides. The majority of HNO3 reduction mechanisms result from aerosolization through heterogeneous reactions, having adverse effects on humans and plants by increasing secondary aerosol concentrations in the atmosphere. The investigation of the formation and conversion mechanisms of HONO and HNO3 is important; however, research in this area is currently lacking. In this study, we observed HONO, HNO3, and their precursor gases were observed in the atmosphere using parallel-plate diffusion scrubber-ion chromatography. A 0-D box model simulated the compositional distribution of NOy in the atmosphere. The formation reactions and conversion mechanisms of HONO and HNO3 were quantified using reaction equations and reaction coefficients. Among the various mechanisms, dominant mechanisms were identified, suggesting their importance. According to the calculation results, the produce of HONO was predominantly attributed to heterogeneous reactions, excluding an unknown source. The sink processes were mainly governed by photolysis during daytime and reactions with OH radicals during nighttime. HNO3 showed dominance in its production from N2O5, and in its conversion mechanisms primarily involving aerosolization and deposition. [ABSTRACT FROM AUTHOR]

Simultaneous determination of 2'-fucosylactose and lacto-N-neotetraose in infant formula milk powder by ion chromatography is studied. These 2 human milk oligosaccharides (HMOs) are separated by ion chromatography, and determined by pulse amperometric detector, and quantified using an external standard method. The method is optimized through analyzing different purification methods, enzymatic hydrolysis treatment, different elution conditions, and the linear range. The effects of determining chromatographic conditions and pre-treatment conditions on separation are compared. The results show that the optimized method has a good linear relationship, with R2 ＞0. 999. It also has good precision and accuracy, which the relative standard deviation (n=7) is ＜2. 7%, and the recoveries of 2'-fucose lactose and lacto-N-neotetraose are 95. 97%~103. 38% and 100. 09%~104. 01%, respectively. This method can simultaneously determine 2' -fucose and lacto-N-neotetraose in infant formula milk powder. It is simple to operate, has good accuracy and precision, and can provide reference for the quality control method of infant formula milk powder. [ABSTRACT FROM AUTHOR]

The sulfur (S) mass fraction of carbonate minerals can be used to reconstruct the environmental conditions and S sources at the time of precipitation. As S is present in a wide range of host materials, there is an urgent need to develop a method to extract S from a single mineral phase. We have developed a method to extract structurally substituted sulfate, termed carbonate‐associated sulfate (CAS), from geological and biogenic carbonate minerals using weakly acidic cation exchange resins. Two types of weakly acidic cation exchange resin (methacrylic acid and acrylic acid types) were tested to minimise the blank S contents and decompose carbonate. After repeated cleaning of the resins with high‐purity water or HCl, the blank S contents were reduced to < 0.1 μg, which is < 0.1% of the CAS in the samples. The cleaned resin was used to dissolve 10 and 25 mg of the JCp‐1 carbonate certified reference material (CRM; Japanese National Institute of Advanced Industrial Science and Technology, AIST). Samples and resin were added to 8 ml of high‐purity water at resin/sample ratios of 2, 5, 10 and 20, set on a shaking table, and reacted. The supernatant solutions were sampled sequentially from 0.5 h to 87 h after the start of experiments. The results show that the optimal conditions for decomposing 10 mg of carbonate is a resin/sample ratio of ≥ 10 with a reaction time of ≥ 40 h. Carbonate‐associated S mass fractions were measured for six geological and biogenic carbonate CRMs. The coefficient of variation in carbonate‐associated S mass fractions was ≤ 7%, regardless of the type of resins used. The mass fractions determined with this method recover 74–94% of the total S mass fractions reported in previous studies, suggesting that this method dissolved carbonate, and did not leach other S‐bearing fractions that are not resistant to weak acids. Another benefit of this method is that the decomposed solution can be introduced directly into the ion chromatograph, allowing for more sensitive analyses. We emphasise that this method can also be used for S isotopic measurements, as S contamination from other S‐bearing mineral phases is low. [ABSTRACT FROM AUTHOR]

The contents of 9 anions and 6 cations in the crystalloid salt on ancient pottery, such as CH3COO, HCOO, F, C1, SO：, N03, Na+, K+, NH4+, Ca2+, Mg2+, were studied and determined by dual channel ion chromatography. Using Metrosep A Supp7 anion chromatographic column as the analytical column, 3 mmol/L NaCO3 as the eluent, the flow rate was 0・ 7 mL/min, using Metrosep C4 cations chromatographic column as the analytical column, 0・ 8 mmol/L C7H5NO4-1・ 6 mmol/L HNO3 as the eluent, the flow rate was 0・ 7 mL/min. Under this method, the purified filtrate is measured by conductivity detector. Each ion formes a good, moderate separation. The detection lini让 was between 0.005 〜 0. 05 mg/L・ The correlation coefficient(5) of the various ions in samples was greater than 0. 999, it has a good linear relationship, the recovery was 96% 〜106%, and the relative standard deviation was 0. 1% 〜 4% (n 二 5). The result showed that the crystal salt on the tile surface mainly contains: Ca2+, Na+, CH3COO, Cl, SO：, NO3 ・ The method is fast and accurate, sensitive and reliable and can be used for the separation and determanation of common organic acid ions and inorganic ions in crystal salts on the surface of cultural relics. [ABSTRACT FROM AUTHOR]

Copyright of China Fiber Inspection is the property of China Fiber Inspection 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.)

It is well known that pollutants affect the deterioration of iron artifacts. To store iron artifacts in a suitable environment, it is imperative to understand the mechanisms of long-term corrosion in museum environments. Although many studies have been carried out to determine the corrosion behavior of iron artifacts, little research has been undertaken to quantify soluble ions in iron corrosion. In this study, the determination of anions in the extraction solution of archaeological iron and iron coupons produced in one-year monitoring experiments was conducted using ion chromatography. Monitoring was carried out in storage and galleries at four museums in different regions of China. The results show that the ion content of the experimental samples, including iron coupons and archaeological iron samples, reflects the atmospheric corrosion environment in the museum, where acetate, formate, and sulfate ions were found present in significant concentrations in the samples. The results produced will provide guides to the accelerated aging experiment of iron with pollutants in the next step of the project. [ABSTRACT FROM AUTHOR]

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher 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.)

This study aims to determine the concentrations of fluoride, nitrite, nitrate, chloride, sulfate, phosphate, calcium, sodium, magnesium, ammonium, and potassium ions in different natural spring water brands available in the markets using ion chromatography. The ion chromatography technique is an accurate, sensitive, and reliable method for determining sample anion and cation concentrations. Measurement range, calibration, method detection level, repeatability, precision, recovery, and standard deviation were evaluated to assess the suitability of the method. The R2 values of anion and cation calibration plots were good (greater than 0.994) in this method. The recovery values for low and high concentrations changed from 101 to 111% and from 97 to 104%, respectively. The concentration results were used for human health risk assessment, using Chronic Daily Intake of nitrate and fluoride. The potential adverse health effects of fluoride intake were less than 1 for adults, so there is no potential risk. Moreover, our results suggest that there is a risk for dental decay according to the fluoride limits in spring water recommended by the World Health Organization. [ABSTRACT FROM AUTHOR]

This standard operating procedure (SOP) describes an ion chromatography (IC) procedure for the major cations and anions in hydrothermal fluids. Hydrothermal fluids are aqueous solutions with a wide range of temperature, salinity, pH and ion species that can be used by microbial metabolism as electron donors and electron acceptors. Due to the high variability of the environmental physical-chemical parameters in these samples, we have developed this protocol taking into account the special features of the matrices analyzed. An Eco IC Metrohm system equipped with a conductivity detector was used. Calibration curves are linear in the 0.1 to 10 mg/L concentration range for cations Ca2+, Na+, K+, Mg2+, NH4 + and anions Cl-, Br-, NO3 -, NO2 -, SO4 2- , PO4 3-.

The analysis of food and drugs as well as the monitoring of chemical processes and bioreactors by high-performance liquid chromatography and ion chromatography requires universal, cost-effective, and sensitive detectors. Therefore, this work presents a split-ring resonator that detects changes in the electrical and dielectric properties of the eluate from liquid chromatography or ion chromatography by monitoring the amplitude of the transmitted signal using an envelope detector. The used split-ring resonator consists of a simple printed circuit board featuring two microstrip lines. One is formed to a ring with interdigital split electrodes. The interdigital split electrodes forming the sensitive area significantly enhance the sensitivity to changes in relative permittivity, dielectric losses and electrical conductivity of the eluate In addition, the split-ring resonator is a small, inexpensive and easy-to-use detector that uses several dielectric parameters simultaneously for the measurement. Furthermore, the split-ring resonator measures these parameters at a significantly lower frequency than optical detectors and therefore measures different changes in frequency-dependent permittivity. For demonstrating feasibility of a split-ring resonator as a detector for high-performance liquid chromatography and ion chromatography, various anion and cation standards, basic and acidic amino acids, sugars, as well as sugar alcohols were separated and detected. A conductivity detector for ion chromatography and a refractive index detector for high-performance liquid chromatography were used as reference detectors.

We developed the LabVIEW-based virtual instruments (VIs) to bridge a gap in commercial software and to enable systematic peak-overlapping studies to recognise the concentration levels enabling reliable simultaneous determination of major and minor constituents in samples with wide concentration proportions. The VIs were applied to a case study of the ion chromatographic determination of potassium as minor and sodium as a major ion with an IonPac CS12A column and 50 μL injection loop. Two successive studies based on multilevel two-factorial response surface experimental designs, (1) a model peak-overlapping study based on single-ion injections, and (2) an accuracy and precision study, provided guidelines for real sample analyses. By adjusting sample dilutions so that the sodium mass concentration was set to 340 mg/L, the simultaneous determination of potassium in the presence of sodium was possible in samples with sodium over potassium concentration ratios between 14 and 341. The relative expanded uncertainty associated with potassium ion determination was between 0.52 and 4.4%, and the relative bias was between −3.8 and 1.9%. We analysed Ringer’s physiologic solutions, standard sea, trisodium citrate anticoagulant, and buffered citrate anticoagulant solutions. We confirmed that the VI-supported peak-overlapping studies contributed to the quality of results by enabling the evidence-based choices of concentration levels adjusted by a dilution.

Heated tobacco products (HTPs) are newly developed nicotine delivery systems via the inhalation of mainstream aerosols generated during the heating of tobacco leaf materials. Previous studies have shown that the amount of chemicals generated is much lower than that generated by conventional combustible cigarettes. However, little attention has been paid to formate, a conjugated base of formic acid with potentially toxic effects on human health. This study aims to understand the actual emission levels and behaviour of formate in mainstream aerosols produced by commercially available HTP devices in Japan. Aerosols were generated from four types of devices with regular and menthol-type flavours using a vaping machine following the CRM 81 puffing protocol. Formate was tapped in 5 mM sodium carbonate solution and subsequently analysed using ion chromatography. The results showed that the total emission amount of formate ranged from 0.0027 ± 0.0031 to 0.27 ± 0.055 mg L−1, varying with heating temperature and flavour type. Moreover, the majority of formate existed in a particulate form due to the weak-basic property of the aerosol, and the formate emission level was much greater than the workplace exposure limit for the direct inhalation of mainstream aerosols. The formate in the mainstream aerosol can be considered a health concern, when using “high-temperature type” HTPs over a long period.

The potential of utilizing inorganic constituents in processed animal proteins (PAPs) for species identification in animal feeds was investigated, with the aim of using these constituents to ensure the quality and authenticity of the products. This study aimed to quantify the inorganic content across various PAP species and assess whether inorganic analysis could effectively differentiate between PAP species, ultimately aiding in the identification of PAP fractions in animal feeds. Four types of PAPs, namely bovine, swine, poultry, and fish-based, were analyzed and compared to others made up of feathers of vegetal-based feed. Also, three insect-based PAPs (Cricket, Silkworm, Flour Moth) were considered in this study to evaluate the differences in terms of the nutrients present in this type of feed. Ionic chromatography (IC) was used to reveal the concentrations of NO3−, NO2, Cl−, and SO42−, and inductively coupled plasma optical emission spectroscopy (ICP-OES) to detect Al, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, P, Si, Sr, Ti, and Zn. The application of multivariate chemometric techniques to the experimental results allowed us to determine the identification capability of the inorganic composition to identify correlations among the variables and to reveal similarities and differences among the different species. The results show the possibility of using this component for discriminating between different PAPS; in particular, fish PAPs are high in Cd, Sr, Na, and Mg content; swine PAPs have lower metal content due to high fat; feathers and vegetal feed have similar Al, Si, and Ni, but feathers are higher in Fe and Zn; and insect PATs have nutrient levels comparable to PAPs of other origins but are very high in Zn, Cu, and K.

To eliminate the interference of calcium phosphate on the determination of calcium carbonate in reconstituted tobacco and to develop an accurate method for determining the mass percentage of calcium carbonate, CO2 was applied to react with calcium carbonate in reconstituted tobacco samples to form water-soluble calcium bicarbonate. Following the treatment, the variation of calcium ion concentration after CO2 treatment was determined by ion chromatography to analyze the mass percentage of calcium carbonate. The feasibility of the method was verified based on the repeatability, recovery, limit of detection (LOD), and limit of quantification (LOQ) . The results showed that: 1) Calcium carbonate could be separated from calcium phosphate by CO2 treatment, and the mass percentage of calcium carbonate in the reconstituted tobacco samples could be accurately determined using three different pretreatment methods. 2) This method showed better repeatability and recovery with a relative standard deviation(RSD, n=5) of 2.69% and recoveries in the range of 95%-102%. The LOD and LOQ were 0.12% and 0.39%, respectively. 3) The variation of the mass percentage of calcium carbonate in different reconstituted tobacco samples was large and varied from 2% to 4% in five reconstituted tobacco samples. In conclusion, this method was convenient, rapid, and suitable for accurate determination of the mass percentage of calcium carbonate in reconstituted tobacco and other complex calcium salt reconstituted tobacco systems. [ABSTRACT FROM AUTHOR]