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This chapter (The Inductively Coupled Plasma) is a contribution to the Geostandards and Geoanalytical Research Handbook of Rock and Mineral Analysis – an online textbook that is a fully revised and updated edition of A Handbook of Silicate Rock Analysis (P. J. Potts, 1987, Blackie, Glasgow).Chapter 5 (from Section 1 of the handbook dealing with fundamentals of measurement and instrument design) is a comprehensive treatment of the inductively coupled plasma – a significant cornerstone of modern geoanalytical spectrometry. The Chapter includes discussion of plasma formation and key components of the ICP source. This is followed by an examination of the challenges of sample introduction into the plasma, particularly focussed on the introduction of liquid samples. The physical structure of the plasma, its robustness and interference effects are fully examined prior to a section dealing with how the operation of plasma is optimised in practise. [ABSTRACT FROM AUTHOR]

This chapter (Geoanalytical Metrology) is a contribution to the Geostandards and Geoanalytical Research Handbook of Rock and Mineral Analysis – an online textbook that is a fully revised and updated edition of Handbook of Silicate Rock Analysis, which was written by Philip J. Potts and published in 1987 by Blackie and Son (Glasgow). This second edition comprises chapters, written by prominent research scientists, designed to provide comprehensive overviews of the relevant techniques for the elemental characterisation of rocks and minerals. Chapters are designed to allow new practitioners to the field (including research students) to attain a comprehensive understanding of the theory, practice and capabilities of each technique, as well as being of benefit to established research geoanalysts. In addition to the content, chapter titles have been revised where appropriate to reflect progress in this field. Chapter 1, Part 1 (from Section 1 of the handbook dealing with fundamentals of measurement and instrument design) first sets out the overarching conventions that operate in analytical chemistry, including a description of the international organisations and systems that regulate the standards governing the discipline. This is followed by coverage of the statistical basis on which geoanalytical data sets are treated, analysed and interpreted, which summarises most of the relevant tests and terminology employed in this field. The methods by which the calibration of measured signals from instrumental techniques is tackled, followed by method validation, which covers aspects including measurement uncertainty, bias, precision and trueness. Sections detailing metrological traceability and quality management conclude this chapter. [ABSTRACT FROM AUTHOR]

This chapter (Quadrupole Inductively Coupled Plasma‐Mass Spectrometry) is a contribution to the Geostandards and Geoanalytical Research Handbook of Rock and Mineral Analysis – an online textbook that is a fully revised and updated edition of Handbook of the Silicate Rock Analysis (P. J. Potts, 1987, Blackie, Glasgow). Chapter 7 (from Section 2 of the handbook dealing with techniques for the determination of major and trace elements) describes both the history of ICP‐MS, including development of the plasma sampling interface and the operation of modern ICP‐MS instrumentation. Given their central importance to ICP‐MS operation, ion extraction through the sampling interface, ion transmission, ion separation (with a particular focus on the quadrupole mass filter) and counting are given particular attention. Discussion of the analytical characteristics of ICP‐MS particularly focusses on spectroscopic interferences (and their mitigation). Finally, an overview of geochemical analysis by ICP‐MS considers drift correction, calibration strategies, and laser ablation microsampling. [ABSTRACT FROM AUTHOR]

Pharmaceuticals are often found in municipal wastewater due to human excretion and disposal of drugs into sewerage systems. Conventional wastewater treatment plants were not designed for pharmaceutical removal and, hence, pharmaceutical concentrations ranging from ng L−1 to μg L−1 are often detected in treated wastewater, with additional treatment required for full removal. This study has investigated the potential of Trametes versicolour laccase enzyme and 2,2'-azino-bis-(3-ethyl-benzthiazoline-6-sulphonic acid) diammonium salt (ABTS) mediator system to degrade sulfamethoxazole, trimethoprim, metronidazole and phenytoin. The best degradation was observed at pH 5 for both sulfamethoxazole (97% in 12 hours) and trimethoprim (44% in 168 hours), using an initial micropollutant concentration of 100 µM, an enzymatic activity between 110–115 U L−1, and an ABTS concentration of 200 µM. Phenytoin and metronidazole were not degraded. Deamination followed by hydroxylation led to the formation of the two major sulfamethoxazole transformation products (TPs), whilst hydroxylation and hydroxylation/demethylation mechanisms formed the majority of the trimethoprim TPs. The sulfamethoxazole and trimethoprim TPs observed from the laccase-ABTS system were similar to the TPs obtained from degradation processes such as advanced oxidation or photodegradation. The laccase-ABTS system shows promise for control of emerging contaminants containing electron donating groups (such as amines and methoxy groups) on aromatic rings in wastewater systems. [ABSTRACT FROM AUTHOR]

Chlorination of amino acids can result in the formation of organic monochloramines or organic dichloramines, depending on the chlorine to amino acid ratio (Cl:AA). After formation, organic chloramines degrade into aldehydes, nitriles and N-chloraldimines. In this paper, the formation of organic chloramines from chlorination of lysine, tyrosine and valine were investigated. Chlorination of tyrosine and lysine demonstrated that the presence of a reactive secondary group can increase the Cl:AA ratio required for the formation of N,N-dichloramines, and potentially alter the reaction pathways between chlorine and amino acids, resulting in the formation of unexpected byproducts. In a detailed investigation, we report rate constants for all reactions in the chlorination of valine, for the first time, using experimental results and modeling. At Cl:AA = 2.8, the chlorine was found to first react quickly with valine (5.4 × 10 4 M-1 s-1) to form N-monochlorovaline, with a slower subsequent reaction with N-monochlorovaline to form N,N-dichlorovaline (4.9 × 102 M-1 s-1), although some N-monochlorovaline degraded into isobutyraldehyde (1.0 × 10-4 s-1). The N,N-dichlorovaline then competitively degraded into isobutyronitrile (1.3 × 10-4 s-1) and N-chloroisobutyraldimine (1.2 × 10-4 s-1). In conventional drinking water disinfection, N-chloroisobutyraldimine can potentially be formed in concentrations higher than its odor threshold concentration, resulting in aesthetic challenges and an unknown health risk. [ABSTRACT FROM AUTHOR]