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Per-and polyfluoroalkyl substances (PFAS) represent a large group of synthetic organic compounds which exhibit unique properties and have been extensively used for consumer and industrial products, resulting in a widespread presence in the environment. Regulation requiring PFAS monitoring has been implemented worldwide due to their potential health and eco-toxicological effects. Targeted methods are commonly used to monitor between twenty to forty PFAS compounds, representing only a small fraction of the number of compounds that may be present. Consequently, there is an increasing interest in complementary non-targeted methods to screen and identify unknown PFAS compounds with the aim to improve knowledge and to generate more accurate models regarding their environmental mobility and persistence.This work details the development of a method that simultaneously provided targeted and nontargeted PFAS analysis. Ultra-high performance liquid chromatography (UHPLC) was coupled to ion mobility-quadrupole time of flight-mass spectrometry (IMS-QTOF-MS) and used to quantify known and screen unknown PFAS in environmental samples collected within the greater Sydney basin (Australia). The method was validated for the quantification of 14 sulfonate-based PFAS, and a non-targeted data analysis workflow was developed using a combination of mass defect analysis with common fragment and neutral loss filtering to identify fluorine-containing species. The optimised method was applied to the environmental samples and enabled the determination of 3-7 compounds from the targeted list and the detection of a further 56-107 untargeted PFAS. This simultaneous analysis reduces the complexity of multiple analyses, and allows for greater interrogation of the full PFAS load in environmental samples.

In a previous publication (1) a method was described which made it possible to study the sorption of bromine and iodine by porous adsorbents over a rather wide pressure range a t several temperatures. At that time the sorption of bromine and iodine by silica gel at several temperatures was reported. Equilibria for adsorption and desorption were established rapidly in the case of silica gel. In the present study on charcoal equilibrium was reached slowly, so that rates of sorption were measured in addition to the determination of the amounts taken up a t equilibrium.The charcoal used in this investigation was prepared from coconut shells. Broken coconut shells were cleaned and then placed in a large Soxhlet extractor where they were successively extracted for prolonged periods with ether, alcohol, and finally water. The extracted shells were coked in a covered iron crucible in a sand bath. The temperature was raised slowly to 550-575'C. and held there for half an hour after the last flammable vapors came off. After cooling the charcoal was crushed and sieved. A portion of 25 g. that passed a 10-mesh and was retained by a 20-mesh sieve was taken for activation. This was packed in a clean silica combustion tube and heated to 850'C. in an electric furnace. Superheated steam from a small boiler was passed over the charcoal for thirty minutes. After cooling, the average loss in weight on activation by steam was found to be 25 per cent of the initial weight. The steam-activated charcoal was then placed in a silica tube and heated to 700'C. while it was evacuated with a pair of Langmuir condensation pumps. The charcoal was protected from mercury vapor by a liquid air trap. After a 24-hour evacuation the charcoal was cooled to room temperature and oxygen admitted. After standing some time in an atmosphere of oxygen the charcoal was again heated and evacuated for a period of 48 hours. The charcoal was then cooled in an atmosphere of nitrogen. On ashing in a platinum crucible the following results were obtained: ash, 0.185 per cent; ash as sulfate, 0.233 per cent; silica, 0.026 per cent.The charcoal was crushed in an agate mortar and that portion used which passed a 60-mesh and was retained by a 100-mesh screen. About 0.2 g.

Translation of the Bible or any other text unavoidably involves a determination about its meaning. There have been different views of meaning from ancient times up to the present, and a particularly Enlightenment and Modernist view is that the meaning of a text amounts to whatever the original author of the text intended it to be. This article analyzes the authorial-intent view of meaning in comparison with other models of literary and legal interpretation. Texts are anchors to interpretation but are subject to individualized interpretations. It is texts that are translated, not intentions. The challenge to the translator is to negotiate the meaning of a text and try to choose the most salient and appropriate interpretation as a basis for bringing the text to a new audience through translation.

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