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Eine Überwachung von Roh- und Trinkwasser ist für eine sichere Trinkwasserversorgung essentiell. Neben gezielter Target-Analytik werden vermehrt Non-Target-Screening-Ansätze genutzt, um auch unbekannte oder unerwartete Spurenstoffe zu erfassen. Beide Analysenmethoden wurden etabliert, um die Donau sowie deren Zuflüsse im Großraum Ulm zu untersuchen. Die höchsten Mediankonzentrationen wurden für hochpolare Stoffe festgestellt. Diese sind besonders in den Fokus zu rücken, da sie aufgrund ihrer Persistenz und Mobilität oft natürliche und technische Barrieren durchschreiten und bis ins Trinkwasser gelangen können. Mehr als die Hälfte der Positivbefunde in der Donau stellten Arznei- und Röntgenkontrastmittel dar. Hier legen unerwartet hohe Konzentrationsspitzen mit großer zeitlicher Varianz einen industriellen Quellenschwerpunkt nahe. Weitere intelligente Probenahme-, Analytik- und Auswertestrategien zur endgültigen Aufklärung werden angestrebt. Dies wird die Grundlage schaffen, um gezielte Maßnahmen im Sinne des vorsorgenden Umwelt- und Gesundheitsschutzes zu ergreifen.

For the analysis of low concentrations of micropollutants in environmental water samples, efficient sample enrichment and cleanup are necessary to reduce matrix effects and to reach low detection limits. For analytes of low and medium polarity, solid-phase extraction is used, but robust methods for the preconcentration of highly polar or ionizable analytes are scarce. In this work, field-step electrophoresis (FSE) was developed as an environmental sample cleanup technique for ionizable micropollutants and ionic transformation products. The FSE electrolyte system preconcentrated 15 acidic model analytes (pKa from −2.2 to 9.1) present in aqueous samples in two fractions by factors of 5–10. Simultaneously, highly mobile matrix compounds were removed including inorganic ions such as sulfate and chloride. The fractions were either directly injected for downstream analysis by reversed-phase liquid chromatography (RPLC) or further processed by evaporative preconcentration with subsequent reconstitution in an organic solvent suitable for separation methods like hydrophilic interaction chromatography. The FSE/RPLC-MS method exhibited high quantitative precision with RSDs of 3–6%. The method was successfully applied to a spiked river water sample and its performance compared with common solid-phase extraction and evaporative concentration, demonstrating a high analyte coverage. FSE combined with non-target screening by RPLC-MS revealed a strong reduction in matrix load especially at low retention times. Seventeen compounds were identified in the FSE fractions sampled at the field step boundary by retention time, accurate mass, and mass fragments. Suspect screening by FSE/RPLC-MS was facilitated by FSE’s selectivity for anionic compounds.

Reversed-phase liquid chromatography (RPLC) used for water analysis is not ideal for the analysis of highly polar and ionic contaminants because of low retention. Capillary electrophoresis (CE), on the other hand, is perfectly suited for the separation of ionic compounds but rarely applied in environmental analysis due to the weak concentration sensitivity when coupled to mass spectrometry (MS). However, novel interface designs and MS technology strongly improve the sensitivity. Here, a method is presented enabling the screening of anionic micropollutants in drinking water without sample pretreatment by coupling of CE to an Orbitrap mass spectrometer by a nanoflow sheath liquid interface. Targeted analysis of halogenated acetic acids, trifluoromethanesulfonic acid, and perfluorooctanoic and perfluorooctanesulfonic acid was conducted in drinking water samples which were chlorinated for disinfection. A bare fused silica capillary with an optimized background electrolyte (BGE) for separation consisting of 10% acetic acid with 10% isopropanol with large volume sample injection and optimized interface parameters offer limits of quantification in the range of 0.993) and repeatability (14% standard deviation in area). Concentrations of the target analytes ranged from 0.1 to 6.2 μg/L in the water samples. Masses corresponding to halogenated methanesulfonic acids have been found as suspects and were subsequently verified by standards. Mono-, dichloro-, and bromochloro methanesulfonic acid were quantified in a range of 0.2 to 3.6 μg/L. Furthermore, five sulfonic acids, four organosulfates, and the artificial sweeteners acesulfame and cyclamate as well as inorganics such as halides, halogenates, phosphate, and sulfate could be determined as suspects among more than 300 features in a non-targeted screening. Overall, this approach demonstrates the great potential of CE-nanoESI-MS for the screening of ionic contaminants in environmental samples, complementary to chromatographic approaches. Electronic supplementary material The online version of this article (10.1007/s00216-020-02525-8) contains supplementary material, which is available to authorized users.

A common way to conserve the aesthetic appearance of High-Performance Concrete (HPC) surfaces against e.g. undesired changes in colour is to apply water-repellent treatment. For this purpose, two types of treatment i.e. film former and penetrants are commonly employed, with film formers developing a continuous film on the surface, whereas penetrants line the near-surface pores of the substrate. In this paper, the performance of these two types of treatment – when subjected to artificial weathering (UV irradiation and humidity) – is assessed by colourimetry, static contact angle (CA) measurements, scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD). The obtained results revealed that both types of treatment led to hydrophobic properties by reducing the surface free energy (SFE) with the extent depending on the chemical functionalities of the used water-repellent agents. The film former successfully hindered water from extracting the soluble calcium-bearing constituents from the hardened cement paste and, thus, prevented the deposition of efflorescence onto the HPC surfaces. The smaller penetration depths of the penetrants due to the low permeability of the investigated HPC, on the other hand, most likely allowed for the formation of transport pathways into the bulk material allowing water to extract the soluble calcium-bearing constituents. Based on the provided experimental basis, the underlying mechanisms of water-repellent treatment when applied to HPC are highlighted and guidelines for the proper selection of surface treatment according to the protection desired are given.

For a long time, historical mortars were primarily associated with mortars based on calcium carbonate as the main binder phase. Recent publications show that considerable amounts of magnesium are often present in the binder of historical mortars, which is referred to the use of dolomite rock as raw material (Diekamp, ​​2009; Diekamp, ​​2014). A special feature are Roman and medieval dolomitic lime mortars with the addition of brick fragments as a pozzolanic component (Schidlowski, 2019).In order to characterize the phase formation in modern pozzolanic dolomitic lime mortars, mortar prisms based on dolomitic lime were produced with three different pozzolans (antique and modern brick dust and metakaolin). To draw comparisons with other binders, identical prisms based on calcite and magnesite were produced. These specimens were stored under different environmental conditions (60 % and 95 % relative humidity) and examined by X-ray diffraction and simultaneous thermal analysis after periods of 28, 90 and 180 days.The results obtained so far show that the binder phases that have evolved in the mortars based on dolomitic lime are calcite, aragonite, portlandite, brucite and AFm phases. Aragonite is only found in traces in the samples with metakaolin. In contrast to the samples stored at 65 % relative humidity, the samples stored at 95 % relative humidity have lower calcite and higher contents of portlandite and AFm phases.No significant differences in the amount of calcite and water-containing mineral phases (portlandite, brucite, hydrotalcite) can be found after 28, 90 and 180 days. It can be concluded that a large part of the reactions has already taken place after 28 days.The present study is believed to be beneficial for a thorough understanding of the phase formations in dolomitic lime based mortars at different curing conditions.

In Tyrol, Austria, dolomite rock was commonly used as raw material for historic mortars and plasters. During calcination of dolomite rock, almost equal amounts of calcium oxide and magnesium oxide are produced. While the reactivity of calcium oxide is well known, the reactivity of magnesium oxide is still not completely understood. Within this study, the reactivity of magnesium oxide obtained from calcination at different temperatures (600 - 1000 °C) will be examined. For this purpose, natural magnesite (Hochfilzen, Tyrol) will be used instead of natural dolomite rock in order to minimise the influence of calcium oxide on the wet slaking curves. Both, calcination and slaking of magnesite will be studied with the help of X-ray diffraction analysis and thermogravimetric analysis. The gained knowledge is believed to be beneficial for improving the understanding of degradation processes. The study was performed within the Interreg V-A Italy-Austria project named DOLOMIA (ITAT 2036) with the funding by INTERact and the European Regional Development Fund (ERDF) being grateful acknowledged.

© 2020 The Authors Chlorothalonil, a fungicide applied for decades worldwide, has recently been banned in the European Union (EU) and Switzerland due to its carcinogenicity and the presence of potentially toxic transformation products (TPs) in groundwater. The spread and concentration range of chlorothalonil TPs in different drinking water resources was examined (73 groundwater and four surface water samples mainly from Switzerland). The chlorothalonil sulfonic acid TPs (R471811, R419492, R417888) occurred more frequently and at higher concentrations (detected in 65–100% of the samples, ≤2200 ngL−1) than the phenolic TPs (SYN507900, SYN548580, R611968; detected in 10–30% of the samples, ≤130 ngL−1). The TP R471811 was found in all samples and even in 52% of the samples above 100 ngL−1, the drinking water standard in Switzerland and other European countries. Therefore, the abatement of chlorothalonil TPs was investigated in laboratory and pilot-scale experiments and along the treatment train of various water works, comprising aquifer recharge, UV disinfection, ozonation, advanced oxidation processes (AOPs), activated carbon treatment, and reverse osmosis. The phenolic TPs can be abated during ozonation (second order rate constant kO3 ∼104 M−1s−1) and by reaction with hydroxyl radicals ([rad]OH) in AOPs (kOH ∼109 M−1s−1). In contrast, the sulfonic acid TPs, which occurred in higher concentrations in drinking water resources, react only very slowly with ozone (kO3, Water Research, 183, ISSN:0043-1354, ISSN:1879-2448

Die Geschichte der Psychiatrie ist eng mit den Begriffen Gewalt und Zwang assoziiert. In unterschiedlichen Studien zeigt sich, dass bis zu 15 % der stationar aufgenommenen Patienten in psychiatrischen Einrichtungen eine Zwangsmasnahme erleben. Besonders psychotische Patienten mit einer schizophrenen Erkrankung haben ein erhohtes Risiko, zwangsbehandelt zu werden, aber auch solche mit organischen psychischen Storungen und Manie. Die Frage, ob Zwangsmasnahmen in der Behandlung psychisch Kranker notwendig sind, wird kontrovers diskutiert. Es gibt zahlreiche Belege fur korperliche und psychische Folgeschaden, sowohl bei den Betroffenen, als auch dem Personal. Derzeit scheint im klinischen Alltag kein volliger Verzicht moglich. Allerdings gibt es verbesserungswurdige Aspekte und nachahmungswerte Alternativen, welche in diesem Ubersichtartikel Erwahnung finden.

Surface treatments are applied to protect concrete from the penetration of water with the purpose of retarding degradation and/or aesthetic deterioration. Several studies have shown that the penetration behaviour of surface treatments for ordinary concrete depends on the substrate moisture content which in turn influences its service life. The role of moisture content in case of surface treatments applied to High-Performance Concrete (HPC) seems to be questionable due to the reduced near-surface permeability and diminished capillary water uptake of HPC. In this paper, the effect of different moisture contents (4, 6, 8 wt.-%) representing dry, medium and wet conditions on the penetration behaviour and the subsequent weatherability of acrylic resin coating are evaluated by means of artificial weathering over a period of 2160 h. Based on the obtained results, the penetration of the used acrylic resin is considered to be hindered by a filter effect due to the reduced pore size in the near-surface area of HPC. Thus, the aqueous dispersion of acrylic resin is separated into solvent (penetrating into the HPC) and active agent (remaining on its surface). With ongoing artificial weathering incremental colour change (brightening) and delamination of the surface treatment are observed, with the extent being more pronounced for specimens with moisture contents of 6 and 8 wt.-%. The observed differences in weathering are considered to be the result of differences in the moisture absorption of the acrylic film. This in turn is mostly related to the saponification of the acrylic resin resulting in the formation of hygroscopic carboxylic acid salts due to the alkaline environment of HPC. Thus, moisture contents of 6 and 8 wt.-% are suspected to facilitate the degradation of the coating by the alkaline pore solution, which increases the extent of saponification making the film more prone to the absorption of moisture. For 4 wt.-% moisture content, on the other hand, the extent of saponification is marginal resulting in only slight changes in colour and a minor degree of delamination.

To close the “analytical gap” in the liquid chromatographic (LC) analysis of highly polar substances, two techniques which have been suggested earlier were tested in terms of retention factors and detection limits: hydrophilic interaction liquid chromatography (HILIC) and mixed-mode chromatography (MMC). A substance mix of 55 analytes ranging from logD − 8.2 to 3.4 and 17 different LC columns, also comprising additional reversed-phase columns were used. Contrary to most reversed-phase columns, column bleed has been identified as an important factor, which may cause serious restrictions during high-resolution mass spectrometric detection (HRMS). We found that highly abundant background masses continuously eluting from the columns heavily influence ion transmission to the detector. As a result, the linear dynamic range as well as the sensitivity decreases and thus limits the HRMS applicability of some columns. We therefore recommend a thorough investigation of ion transmission during HRMS method development. This will help to maintain the high potential of HRMS in terms of qualitative and quantitative screening analysis.

Renders, plasters and masonry mortars based on natural hydraulic lime (NHL) are very common materials in the alpine area of Tyrol as shown by numerous application fields in cultural heritage preservation building sites. A sufficient resistance to frost damage and the crystallization of building salts are the most important requirements in regard to a long-term durability in critical environments. Up to now, the literature provides different types of frost-thaw and salt resistance testing methods, but not perspicuously tailored for NHL- or lime-based mortars. Hence, the present study aimed to assess cyclic frost-thaw and salt exposing test methods concerning the long-term durability of NHL-based mortar materials. Furthermore, we intended to relate the testing procedures to application fields occurring on building sites under consideration of the exposure conditions occurring in the alpine region. In order to cover a broad spectrum of possible applications, we operated with several testing methods mentioned in the literature, working with varying test setups. Moreover, we applied interstitial test procedures, which have been partly adapted and aligned in some details, to close the gap between the different methods. Regarding the investigated materials, we focused on different mortars actually applied on historic objects in Tyrol. Thus, the comparison with the effective properties occurring in the specific application field of a building becomes facilitated. Within the frame of the current study, it was figured out that it is reasonable to distinguish between dynamic and static testing setups. In addition, it was observed that it is required to confine the use of the materials under question in consideration of a static or dynamic application area at the building object. If a general assessment is required, we recommend a combined test consisting of both methodical approaches, operating with the equal frost-thaw cycle. Moreover, the results reveal that parts of the operated testing series (e.g. a combination of methods) allow useful estimations about the durability of the materials in relation to their application range. Key parameters ascertainable from porosity and water transport measurements additionally help to understand the experimental data and to evaluate the reliability of the results.

Natural hydraulic lime (NHL) is a common binder material in historic mortars and becomes increasingly used in recent restoration works for the preservation of cultural heritage. These plasters, renders and masonry mortars are suitable for applications, where elevated water permeable characteristics are required. At the building site different workmanship methods may be used, which can be simulated by e.g. different mixing times. Hence, within the present study two NHL-based recipes using hydrated lime of different origin (dry powder and lime putty suspension) were evaluated with regard to the effect of different mixing methods and water content on fresh and hardened mortar characteristics based on a comprehensive experimental program. Additionally, the porosity was evaluated by direct and indirect methods for assessing the water transport behaviour. Although durability and the underlying water transport properties are strongly related to porosity, this study focused primarily on this essential interrelation described by key parameters found in literature and evolved within this study. The results revealed that the mixing method and its associated water content as well as the type of hydrated lime affect strongly the fresh and hardened mortar properties. The pore structure characteristics that resulted from different fresh mortar treatment are crucial for the developing of durability. The observed interrelation between the aforementioned characteristics is essential for a deeper understanding of NHL-based systems. Generally, a longer treatment time leads to a higher durability against e.g. like frost-thaw and salt exposure. Considering the evaluated characteristics, it is possible to apply a prediction model based on the introduced key parameters to obtain information about the estimated resistance of NHL-based renders against damaging processes. Thus, the gained insights are beneficial for a comprehensive scheduling of restoration approach with specified framework requirements and arranged general material selection.

This article focuses on the data evaluation of non-target high-resolution LC-MS profiles of water samples. Taking into account multiple technical replicates, the difficulties in peak recognition and the related problems of false positive and false negative findings are systematically demonstrated. On the basis of a combinatorial approach, different models involving sophisticated workflows are evaluated, particularly with regard to the repeatability. In addition, the improvement resulting from data processing was systematically taken into consideration where the recovery of spiked standards emphasized that real peaks of interest were barely or not removed by the derived filter criteria. The comprehensive evaluation included different matrix types spiked with up to 263 analytical standards which were analyzed repeatedly leading to a total number of more than 250 injections that were incorporated in the assessment of different models of data processing. It was found that the analysis of multiple replicates is the key factor as, on the one hand, it provides the option of integrating valuable filters in order to minimize the false positive rate and, on the other hand, allows correcting partially false negative findings occurring during the peak recognition. The developed processing strategies including replicates clearly point to an enhanced data quality since both the repeatability as well as the peak recognition could be considerably improved. As proof of concept, four different matrix types, including a wastewater treatment plant (WWTP) effluent, were spiked with 130 isotopically labeled standards at different concentration levels. Despite the stringent filter criteria, at 100 ng L(-1) recovery rates of up to 93% were reached in the positive ionization mode. The proposed model, comprising three technical replicates, filters less than 5% and 2% of the standards recognized at 100 and 500 ng L(-1), respectively and thus indicates the general applicability of the presented strategies.

The durability of concrete and concrete structures is significantly influenced by environmental conditions, resulting in e.g. the ingress of water and incorporated aggressive agents, with the latter being responsible for initiating and progress of deterioration processes within the material system. In order to reduce the ingress of water, water repellent agents are applied onto the concrete surface (surface treatment), with its performance strongly depending on the agent itself, the mode of application, environmental conditions etc. For the assessment of the performance of surface-treated concrete, standard test methods, such as Karsten-Tube penetration test, contact angle measurement, hydrophobic quality test, as well as more refined test methods, such as Infrared Spectroscopy (IR), moisture sorption analysis, and scanning electron microscopy coupled with elemental X-ray analysis (SEM/EDS) are used. These methods are commonly employed for the assessment of surface-treated ordinary concrete, leaving the question on their applicability to material systems exhibiting a denser microstructure, such as High Performance Concrete (HPC), unanswered. Within this experimental study, the aforementioned test methods are critically reviewed regarding their potential application to HPC, finally providing recommendations for evaluating the performance and durability of water-repellent surface treatment when applied to HPC.

Surface treatment is recommended for the protection of High-Performance Concrete (HPC) against weathering. This laboratory study highlighted the underlying weathering mechanisms of treated HPC surfaces when cyclically exposed to UV irradiation and condensation. The extent of the weathering-induced changes in colour of the acrylic films (perceived as opacity of former transparent films) were revealed to depend on the application amount (associated with film toughness) and the application method (associated with film quality). To ensure long-lasting protection through surface treatment, the films have to be free of pinholes and sufficiently thick in order to withstand stresses resulting from weathering.

Psychiatric treatment has always been associated with violence and coercion. Involuntary admission and coercive measures are still frequently occurring components in everyday clinical practice.Up to 15% of psychiatric inpatients experience coercive treatment at least once during hospital stay. Particularly patients suffering from schizophrenia, organic mental disorders and mania have a high risk for such incidents.There is an ongoing intense debate on the need and justification of coercive measures, although most clinicians and scientists currently agree that there is no alternative. Several investigations have shown that seclusion and mechanical restraint go along with physical and psychological problems affecting both, patients and staff. However, it was possible to identify aspects that could be improved: Maintaining an objective and professional communication during coercive treatment seems just as important as making comprehensible decisions. Alternative treatment options should be focus of further investigations.

The behavior of micropollutants in water treatment is an important aspect in terms of water quality. Nontarget screening by liquid chromatography coupled to high-resolution mass spectrometry (LC-HRMS) offers the opportunity to comprehensively assess water treatment processes by comparing the signal heights of all detectable compounds before and after treatment. Without preselection of known target compounds, all accessible information is used to describe changes across processes and thus serves as a measure for the treatment efficiency. In this study, we introduce a novel LC-HRMS data processing strategy for the reliable classification of signals based on the observed fold changes. An approach for filtering detected features was developed and, after parameter adjustment, validated for its recall and precision. As proof of concept, the fate of 411 target compounds in a 0.1 μg/L standard mix was tracked throughout the data processing stages, where 406 targets were successfully recognized and retained during filtering. Potential pitfalls in signal classification were addressed. We found the recursive peak integration to be a key point for the reliable classification of signal changes across a process. For evaluating the repeatability, a combinatorial approach was conducted to verify the consistency of the final outcome using technical replicates of influent and effluent samples taken from an ozonation process during drinking water treatment. The results showed sufficient repeatability and thus emphasized the applicability of nontarget screening for the assessment of water treatment processes. The developed data processing strategies may be transferred to other research fields where sample comparisons are conducted.

This contribution focuses on the application of non-targetscreening by liquid chromatography-high resolution massspectrometry (LC-HRMS) as a tool in routine water analysis. From the perspective of water suppliers, comprehensivemonitoring strategies are required to ensure good water quality.We will illustrate the strengths of the non-target approachesbased on three chosen case studies. In principal, the non-targetanalysis enables monitoring approaches which also coverunknown or unexpected contaminants. The archive function ofHRMS data comprises various benefits such as retrospectivescreening and also allows determining concentrations in asemi-quantitative way. Temporal prioritization in combinationwith multivariate statistics emerged as helpful strategy forthe detection of new contaminants. This is exemplified for the identification of a spill event in river water. The spatialsampling information, on the other hand, allows the localization of possible sources of contamination. Prioritization basedon the analytical request reduces thousands of signals to fewinteresting candidates which increases the success rate duringthe identification. By such measures, it was possible to provethat a groundwater contamination is caused by an industrialwaste water treatment plant. For the evaluation of processes for water treatment, identification and quantification of individualcontaminants is not always of major interest. However,sophisticated strategies are needed to compare the purificationefficiency of new technologies to already established ones.Here we evaluated the effectiveness of the fourth treatment stepbased on activated carbon filtration in waste water treatmentplants.

Hartmetalle auf der Basis WC-Co weisen die gunstigste Kombination mechanischer Eigenschaften, verglichen mit WC-Ni-Sorten auf, jedoch ist ihre Korrosionsbestandigkeit in vielen Fallen nur ungenugend. Sowohl durch die Variation der Bindephase (Ni, Ni-Cr), als auch durch Variation der Karbidphase (Korngrose) gelingt es, die Korrosionsbestandigkeit von Hartmetallen dem jeweiligen Einsatzfall, unter Erhaltung der gunstigen mechanischen Eigenschaften, besser anzupassen. Es werden die mechanischen, chemischen und thermischen Eigenschaften verschiedener Hartmetall-Zusammensetzungen vorgestellt. Hartmetall modifizierter Zusammensetzung kann fur Ventilteile, Gleitringe, Dusen und fur diverse Verschleisteile in der chemischen Industrie eingesetzt werden. Durch ihre metallische Natur sind Hartmetalle in ihren mechanischen Eigenschaften in vielen Fallen der sehr korrosionsresistenten Keramik uberlegen. Durch Auswahl geeigneter Binde-und Karbidphasen gelingt es, bei erwunschter guter Korrosionsbestandigkeit, ein Maximum von Festigkeit, Zahigkeit und Harte zu erreichen. Corrosion and highly wear resistant hard metals Hard metals based on WC-Co have a better combination of mechanical properties compared to WC-Ni grades, but their corrosion resistance is generally poor. Either by variation of the binder phase (Ni, Ni-Cr) or by variation of the carbide phase (grain size) the corrosion resistance of hard metals can be tailored to the specific application maintaining the good mechanical properties of WC-Co-grades. The mechanical, chemical and thermal properties of various hard metal compositions are given. Hard metals of modified composition are used for valve parts, seal rings, nozzles and as wear parts for other applications in chemical industry. By their metallic nature, hard metals are still superior to ceramics in their mechanical strength, although ceramics show in general the excellent corrosion resistance. By optimising the carbide and binder phase in hard metals, improved corrosion resistance together with the good mechanical properties of WC-Co can be achieved.