Use of an in situ artificial substrate for biological accumulation and monitoring of aqueous trace metals a preliminary field investigation

Thousands of pollutants are threatening our water supply, putting at risk human and environmental health. Between them, trace metals are of significant concern, due to their high toxicity at low concentrations. Abandoned mining areas are globally one of the major sources of toxic metals. Nowadays, no method can guarantee an immediate response for quantifying these pollutants. In this work, a novel technique based on microwave spectroscopy and planar sensors for in situ real-time monitoring of water quality is described. The sensors were developed to directly probe water samples, and in situ trial measurements were performed in freshwater in four polluted mining areas in the UK. Planar microwave sensors were able detect the water pollution level with an immediate response specifically depicted at three resonant peaks in the GHz range. To the authors’ best knowledge, this is the first time that planar microwave sensors were tested in situ, demonstrating the ability to use this method for classifying more and less polluted water using a multiple-peak approach.

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In situ measurement of trace metals in lakewater using the dialysis and DGT techniques

Analytica Chimica Acta ◽

10.1016/s0003-2670(00)00946-6 ◽

2000 ◽

Vol 418 (1) ◽

pp. 53-68 ◽

Cited By ~ 75

Author(s):

Maria Catalina Alfaro-De la Torre ◽

Pierre-Yves Beaulieu ◽

André Tessier

Keyword(s):

Trace Metals ◽

In Situ Measurement

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The control of hydrogen sulfide on benthic iron and cadmium fluxes in the oxygen minimum zone off Peru

10.5194/bg-2019-390 ◽

2019 ◽

Author(s):

Anna Plass ◽

Christian Schlosser ◽

Stefan Sommer ◽

Andrew W. Dale ◽

Eric P. Achterberg ◽

...

Keyword(s):

Hydrogen Sulfide ◽

Trace Metals ◽

Pore Water ◽

Oxygen Minimum Zone ◽

Benthic Fluxes ◽

Benthic Chamber ◽

Bottom Waters ◽

Minimum Zone ◽

Oxygen Minimum

Abstract. Sediments in oxygen-depleted marine environments can be an important sink or source of bio-essential trace metals in the ocean. However, the key mechanisms controlling the release from or burial of trace metals in sediments are not exactly understood. Here, we investigate the benthic biogeochemical cycling of Fe and Cd in the oxygen minimum zone off Peru. We combine bottom water profiles, pore water profiles, as well as benthic fluxes determined from pore water profiles and in-situ from benthic chamber incubations along a depth transect at 12° S. In agreement with previous studies, both concentration-depth profiles and in-situ benthic fluxes indicate a Fe release from sediments into bottom waters. Diffusive Fe fluxes and Fe fluxes from benthic chamber incubations are roughly consistent (0.3–17.1 mmol m−2 y−1), indicating that diffusion is the main transport mechanism of dissolved Fe across the sediment-water interface. The occurrence of mats of sulfur oxidizing bacteria on the seafloor represents an important control on the spatial distribution of Fe fluxes by regulating hydrogen sulfide (H2S) concentrations and, potentially, Fe sulfide precipitation within the surface sediment. Removal of dissolved Fe after its release to anoxic bottom waters is rapid in the first 4 m away from the seafloor (half-life

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Using CPTs to derive thermal properties of soil

E3S Web of Conferences ◽

10.1051/e3sconf/202020504005 ◽

2020 ◽

Vol 205 ◽

pp. 04005

Author(s):

Philip J. Vardon ◽

Joek Peuchen

Keyword(s):

Thermal Conductivity ◽

Heat Capacity ◽

Laboratory Tests ◽

Field Investigation ◽

Volumetric Heat Capacity ◽

Cone Penetration ◽

Cone Penetration Tests ◽

Penetration Tests ◽

Properties Of Soil

A method of utilizing cone penetration tests (CPTs) is presented which gives continuous profiles of both the in situ thermal conductivity and volumetric heat capacity, along with the in situ temperature, for the upper tens of meters of the ground. Correlations from standard CPT results (cone resistance, sleeve friction and pore pressure) are utilized for both thermal conductivity and volumetric heat capacity for saturated soil. These, in conjunction with point-wise thermal conductivity and in situ temperature results using a Thermal CPT (T-CPT), allow accurate continuous profiles to be derived. The CPT-based method is shown via a field investigation supported by laboratory tests to give accurate and robust results.

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The Wiluna Meteorite fall, Western Australia—2 September 1967

Mineralogical Magazine ◽

10.1180/minmag.1970.037.292.02 ◽

1970 ◽

Vol 37 (292) ◽

pp. 880-887 ◽

Cited By ~ 3

Author(s):

G. J. H. McCall ◽

P. M. Jeffery

Keyword(s):

Western Australia ◽

British Museum ◽

Field Investigation ◽

Reasonable Estimate ◽

Total Recovery ◽

Nickel Iron ◽

Australian Museum ◽

Meteorite Fall ◽

Western Australian

SummaryThe fall of a shower of meteorites numbering several hundred fragments at Wiluna, Western Australia, on the night of 2 September 1967, has been investigated. Although the dispersion ellipse had been largely obscured by removal of fragments before a party of scientists were able to make a field investigation, it has, nevertheless, been possible to make a reasonable estimate of the shower distribution pattern. In spite of this removal of fragments, a number of pieces of meteorite were still found in situ. The bulk of the total recovery is in the collections of the Western Australian Museum, and the physical characteristics of these masses and their petrography is described. In all, some 490 individual fusion-crust coated stones and a large number of broken stony fragments are known to have been recovered. The meteorite is an olivine bronzite chondrite remarkably rich in discrete nodules of nickel iron, up to an inch across, commonly aggregated with troilite. A full chemical analysis of this fresh meteoritic material has been supplied by the British Museum (Natural History).

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