The production and application of PET tracers has been a unique step in the progress of nuclear medicine in last two decades. The most important PET tracers include F-18, C-11 and N-13 radioisotopes and many nuclear medicine centers throughout the globe are using them. However some new tracers are under their way to the mass administration, currently being in th...

A novel strategy is proposed for the efficient simulation of geochemical tracers in ocean models. The method captures the tracer advection and diffusion in a general circulation model (GCM) without any alteration (or even knowledge) of the GCM code. In comparison with offline tracer models, the proposed method is considerably more efficient and automatically includes all parameterizations of un...

An analytical method that employs ion chromatography has been developed to exploit the use of fluorobenzoic acids (FBAs) and halides more fully as hydrologic tracers. In a single run, this reliable, sensitive, and robust method can simultaneously separate and quantify halides (fluoride, chloride, bromide, and iodide) and up to seven FBAs from other common groundwater constituents (e.g. nitrate ...

Major and trace element concentrations were measured in bedrock, regolith and stream sediments from a first-order catchment developed entirely on grey shale in central Pennsylvania, USA. These elements can be classified into five major groups based on statistical data analysis. The presence of different elemental groups is due to the mineralogical origin, cycling processes, and geochemical prop...

Water stored as ice and snow at high elevations is a resource that plays an important role in the hydrologic cycle, particularly in the timing and volume of downstream discharge. Here we use geochemical and isotopic values of water samples to evaluate relative contributions of melting glacier ice and groundwater to discharge in Bhutan. River water samples were collected between 3100 and 4500m i...

Diamictites are poorly sorted sediments characteristically carrying coarse-grained clasts in a fine-grained matrix. They have generally been considered of glaciogenic or glaciomarine origin. Recently, however, it has been suggested that some massive tillite/diamictite layers could represent impact breccias. An earlier petrographic study of rock and mineral clasts from Dwyka Group diamictites re...

Advances in drilling technologies and production strategies such as horizontal drilling and hydraulic fracturing have significantly improved the production of natural gas by stimulating fluid flow from wells. Since 2008, these technological developments have spurred exponential growth of gas well drilling across the U.S. While the new drilling for shale gas and hydraulic fracturing technologies...

Three independent tracer experiments were conducted to quantify the through-flow of water from Herman Pit, an abandoned mercury (Hg) mine pit adjacent to Clear Lake, California, USA. The tracers used were Rhodamine-WT, sulfur hexafluoride, and a mixture of sulfur hexafluoride and neon-22. The tracers were injected into Herman Pit, a generally well-mixed water body of approximately 81,000 m2, an...