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Université de Neuchâtel

Assessing the role of trichloroacetyl-containing compounds in the natural formation of chloroform using stable carbon isotopes analysis

Breider, F ; Albers, C.N ; Hunkeler, Daniel

In: Chemosphere, 2013, vol. 90, p. 441-448

Chloroform (CHCl3) is an environmental contaminant widely distributed around world, as well as a natural compound formed in various aquatic and terrestrial environments. However, the chemical mechanisms leading to the natural formation of chloroform in soils are not completely understood. To assess the role of trichloroacetyl-containing compound (TCAc) in the natural formation of...

Université de Neuchâtel

Direct-push multilevel sampling system for unconsolidated aquifers

Ducommun, P ; Boutsiadou, X ; Hunkeler, Daniel

In: Hydrogeology Journal, 2013, vol. 21, p. 1901-1908

An economical multilevel groundwater monitoring system has been developed that can be rapidly installed with a direct-push machine, yet is suitable for sampling across large permeability contrasts. This sealed multiport sampling (SMPS) system consists of up to five lengths of PVC tubing (12mm OD), each with a screen at a specific depth created by drilling 2.5-mm holes. Above and below each...

Université de Neuchâtel

Regulation of body volume by salivation in a tick challenged with fluid loads

Kaufman, W. R. ; Aeschlimann, André ; Diehl, Peter A.

In: American Journal of Physiology, 1980, vol. 238, no. 1, p. R102-R112

Injection into the hemolymph of 1.2% NaCl, 11.2% sucrose, 2.3% urea (all approximately isosmotic to hemolymph), or distilled water induced salivary fluid secretion in the ixodid tick Amblyomma hebraeum Koch. Saline gave the largest response at high doses. Injection of hyperosmotic NaCL into the hemolymph did not induce salivation but led to the drinking of distilled water in amounts sufficient to...

Université de Neuchâtel

Influence of a Mesogenic Dendrimer on the Morphology of Polymer–Fullerene Composites for Photovoltaics

Kasdorf, Olga ; Kitzerow, Heinz-Siegfried ; Lenoble-Zwahlen, Julie ; Deschenaux, Robert

In: Japanese Journal of Applied Physics, 2010, vol. 49, no. 1S, p. 01AF01 1-4

The efficiency of "bulk hetero junction"-type plastic solar cells depends crucially on the morphology of an entangled network of two immiscible compounds that serve as electron donor and electron acceptor, respectively. The present work describes preliminary results about the question how the luminescence and the morphology of a composite containing a fullerene C60 derivative and a...

Université de Neuchâtel

A Long-Lasting Relaxation of Seismicity at Aswan Reservoir, Egypt, 1982-2001

Mekkawi, Mahmoud ; Grasso, J.-R. ; Schnegg, Pierre-André

In: Bulletin of the Seismological Society of America, 2004, vol. 94, no. 2, p. 479-492

The Aswan reservoir seismicity is accepted as an example of reservoir-induced seismicity with the M 5.4 event of 1981, which occurred 15 years after the reservoir impoundment started. During the 1982-2001 period, the Aswan seismicity separates into shallow and deep seismic zones, between 0 and 15 and 15 and 30 km, respectively. These two seismic zones behave differently over time, as...

Université de Neuchâtel

Phosphorus and the roles of productivity and nutrient recycling during oceanic anoxic event 2

Mort, Haydon P. ; Adatte, Thierry ; Föllmi, Karl B. ; Keller, Gerta ; Steinmann, Philipp ; Matera, Virginie ; Berner, Zsolt ; Stüben, Doris

In: Geology, 2007, vol. 35, no. 6, p. 483-486

Four sections documenting the impact of the late Cenomanian oceanic anoxic event (OAE 2) were studied in basins with different paleoenvironmental regimes. Accumulation rates of phosphorus (P) bound to iron, organic matter, and authigenic phosphate are shown to rise and arrive at a distinct maximum at the onset of OAE 2, with an associated increase in δ13C values. Accumulation rates of...

Université de Neuchâtel

Phosphogenesis and organic-carbon preservation in the Miocene Monterey Formation at Naples Beach, California—The Monterey hypothesis revisited

Föllmi, Karl B. ; Badertscher, Christophe ; de Kaenel, Eric ; Stille, Peter ; John, Cédric M. ; Adatte, Thierry ; Steinmann, Philipp

In: GSA Bulletin, 2005, vol. 117, no. 5-6, p. 589-619

The middle part of the Miocene Monterey Formation at Naples Beach, west of Santa Barbara, California, is predominantly composed of organic-rich mudstone interstratified with phosphatic laminae. Minor lithologies include volcanic ash, dolomite, porcelanite and chert, and condensed phosphatic beds. Sediments dated as 14.3–13.5 Ma have average total organic carbon (TOC) values around 8.5 wt%, and...

Université de Neuchâtel

Glarus overthrust: A major pathway for the escape of fluids out of the Alpine orogen

Badertscher, Nicolas P. ; Beaudoin, Georges ; Therrien, René ; Burkhard, Martin

In: Geology, 2001, vol. 30, no. 10, p. 875-878

Thrust-related fluid flow coupled with isotopic exchange between fluid and rock is simulated in a three-dimensional finite-element model of the Glarus nappe, eastern Swiss Alps. Numerical simulations are matched against well-established oxygen isotope gradients on the kilometer scale along the thrust. At internal southern locations, strongly channelized thrust-parallel fluid flow requires a high...

Université de Neuchâtel

Near vertical iso-illite-crystallinity surfaces cross-cut the recumbent fold structure of the Morcles nappe, Swiss Alps

Burkhard, Martin ; Goy-Eggenberger, D.

In: Clay Minerals, 2001, vol. 36, p. 159-170

Metamorphic isograd surfaces are mapped within the Morcles nappe using illite crystallinity (IC) and (clay-) mineral parageneses in 268 samples. The diagenesis-anchizone and the anchizone-epizone boundaries are nearly vertical surfaces which crosscut the present-day recumbent fold nappe structure. Frontal parts of the nappe are diagenetic (Tmax <200°C) whereas rear parts both...