Organic matter (OM) causes many problems in drinking water treatment. It is difficult to monitor OM concentrations and character during treatment processes due to its complexity. Fluorescence ...spectroscopy is a promising tool for online monitoring. In this study, a unique dataset of fluorescence excitation emission matrixes (EEMs) (n = 867) was collected from all treatment stages of five drinking water treatment plants (WTPs) situated in diverse locations from subtropical to temperate climate. The WTPs incorporated various water sources, treatment processes and OM removal efficiencies (DOC removal 0%-68%). Despite these differences, four common fluorescence PARAFAC components were identified for characterisation of OM concentration and treatability. Moreover, fluorescence component ratios showed site-specific statistically significant correlations with OM removal, which contrasted with correlations between specific UV absorbance at 254 nm (SUVA) and OM removal that were not statistically significant. This indicates that use of fluorescence spectroscopy may be a more robust alternative for predicting DOC removal than UV spectroscopy. Based on the identified fluorescence components, four optical locations were selected in order to move towards single wavelength online OM monitoring.
Membrane fouling in reverse osmosis (RO) systems caused by organic matter (OM) remains a significant operational issue during desalination. Dissolved air flotation (DAF) has recently received ...attention as a pre-treatment option for seawater OM removal; however, only a limited number of studies have been undertaken. This may be because it is difficult to characterise OM in seawater due to the high salt content and low carbon concentration. In this study, DAF pre-treatment experiments were conducted using a model seawater solution, and real seawater and brackish water samples. DAF performance was determined via conventional water quality parameters as well as fluorescence excitation–emission matrix (FEEM) spectroscopy and liquid chromatography with organic carbon detection (LC-OCD). Biopolymers and humic substances were the major organic fractions removed between 38 and 84% and 20–61% depending on the sample, respectively. The optimal normalised coagulant dose (Fe3+ to DOC ratio) was observed to be 0.5–4 at pH5.5 increasing to 4–12 at pH7.5. At pH5.5, the optimum coagulant dose increased with increasing humic character of the feed water. Overall, the OM removal efficiency by DAF observed in this study was higher than reported for other membrane-based processes; a combination of DAF and biofiltration is likely to be complementary.
•Use of DAF for organic matter removal is a good option in desalination systems•High removal of biopolymers and humic substances were observed using coagulation- DAF•Optimal coagulant dose was dependent on humic substance concentration
The determination of delta 13C values in speleothems is of considerable importance in palaeoenvironmental research, but has focussed solely on analysis of the carbonate. Here we demonstrate a new ...method for analysing the delta 13C values of organic matter (OM) trapped in speleothems, utilising flow injection liquid chromatographyaisotope ratio mass spectrometry (LCaIRMS). Developmental analysis using a homogenised speleothem powder showed that the method is robust, with repeated digests and analyses having an average standard deviation of 0.1aDG. Dilution tests with samples of 4a23 mu g total organic carbon (TOC) show relatively small linearity effects, with the overall standard deviation across a peak response range of 1700a9000 mV being 0.2aDG.
The determination of δ13C values in speleothems is of considerable importance in palaeoenvironmental research, but has focussed solely on analysis of the carbonate. Here we demonstrate a new method ...for analysing the δ13C values of organic matter (OM) trapped in speleothems, utilising flow injection liquid chromatography–isotope ratio mass spectrometry (LC–IRMS). Developmental analysis using a homogenised speleothem powder showed that the method is robust, with repeated digests and analyses having an average standard deviation of 0.1‰. Dilution tests with samples of 4–23μg total organic carbon (TOC) show relatively small linearity effects, with the overall standard deviation across a peak response range of 1700–9000mV being 0.2‰.
This article reports the first application of coupled total organic carbon cavity ring-down spectroscopy (TOC-CRDS) for the analysis of the δ13C signature of dissolved organic carbon (DOC) in ...freshwater samples. DOC represents a major, dynamic component of the global carbon cycle. The export of DOC from soils into rivers and groundwaters may be highly climate sensitive, and much of this export may occur in ephemeral fluxes. Thus, a robust, simple and inexpensive method for the continuous determination of DOC concentration and quality is urgently needed. We detail recent advances made in the analysis of the δ13C signature of DOC using a TOC-CRDS system optimised for the analysis of DOC with natural abundances greater than 2.5 mg L−1 with no sample pre-concentration required and sample volumes of 40 mL. Precision between replicated samples was comparable to conventional analysis by gas-source isotope ratio mass spectrometry, yielding δ13C values with standard deviations of ± 0.5 ‰ for DOC concentrations higher than 1.5 mg L−1. The utility of this technique for the analysis of DOC in samples with a broad range of compositions and concentrations (2.5–25 mg L−1 DOC) is demonstrated. Since DOC δ13C can be measured continuously, ca. 45 min per measurement, this method enables the online monitoring of DOC in river water, water intakes and treated waters, allowing changes in DOC fluxes to be monitored in real time.
This article reports the first application of coupled total organic carbon cavity ring-down spectroscopy (TOC-CRDS) for the analysis of the delta super(13)C signature of dissolved organic carbon ...(DOC) in freshwater samples. DOC represents a major, dynamic component of the global carbon cycle. The export of DOC from soils into rivers and groundwaters may be highly climate sensitive, and much of this export may occur in ephemeral fluxes. Thus, a robust, simple and inexpensive method for the continuous determination of DOC concentration and quality is urgently needed. We detail recent advances made in the analysis of the delta super(13)C signature of DOC using a TOC-CRDS system optimised for the analysis of DOC with natural abundances greater than 2.5 mg L super(-1) with no sample pre-concentration required and sample volumes of 40 mL. Precision between replicated samples was comparable to conventional analysis by gas-source isotope ratio mass spectrometry, yielding delta super(13)C values with standard deviations of plus or minus 0.5 ppt for DOC concentrations higher than 1.5 mg L super(-1). The utility of this technique for the analysis of DOC in samples with a broad range of compositions and concentrations (2.5-25 mg L super(-1) DOC) is demonstrated. Since DOC delta super(13)C can be measured continuously, ca. 45 min per measurement, this method enables the online monitoring of DOC in river water, water intakes and treated waters, allowing changes in DOC fluxes to be monitored in real time.
This article reports the first application of coupled total organic carbon cavity ring-down spectroscopy (TOC-CRDS) for the analysis of the δ^sup 13^C signature of dissolved organic carbon (DOC) in ...freshwater samples. DOC represents a major, dynamic component of the global carbon cycle. The export of DOC from soils into rivers and groundwaters may be highly climate sensitive, and much of this export may occur in ephemeral fluxes. Thus, a robust, simple and inexpensive method for the continuous determination of DOC concentration and quality is urgently needed. We detail recent advances made in the analysis of the δ^sup 13^C signature of DOC using a TOC-CRDS system optimised for the analysis of DOC with natural abundances greater than 2.5 mg L^sup -1^ with no sample pre-concentration required and sample volumes of 40 mL. Precision between replicated samples was comparable to conventional analysis by gas-source isotope ratio mass spectrometry, yielding δ^sup 13^C values with standard deviations of ± 0.5 per thousand for DOC concentrations higher than 1.5 mg L^sup -1^. The utility of this technique for the analysis of DOC in samples with a broad range of compositions and concentrations (2.5-25 mg L^sup -1^ DOC) is demonstrated. Since DOC δ^sup 13^C can be measured continuously, ca. 45 min per measurement, this method enables the online monitoring of DOC in river water, water intakes and treated waters, allowing changes in DOC fluxes to be monitored in real time.PUBLICATION ABSTRACT
The purpose of the study is a comprehensive analytical review of various sources that reveal the role of music in Krasnoyarsk by the outbreak of the war.
A hypothesis: interdependence of cultural and ...social events and their mutual influence during a period of increased social tension could be observed.
Methods. During the study the following research methods were applied: cultural-historical, axiological, continuous sampling, descriptive methods and elements of statistical research. Materials published on the pages of the Krasnoyarsk periodicals for 1937–1941, as well as scientific works about music education and music culture by various outstanding scientists were used.
Results. It was proved that music education by the outbreak of the war is considered a foundation for the realization of ideological and educational purposes. And it is also outlined that The Great Patriotic War set new challenges in the cultural life of the Krasnoyarsk Territory in general and Krasnoyarsk in particular.
It is concluded that music education is considered a resource for the national solidarity building. Due to such a strong foundation, music education at the beginning of the war was able to fulfil an ideological function while concert musical activities were used as a tool for creating of civic identity.
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