Groundwater contamination by fluoride (F) can result from the natural dissolution of minerals from subterranean strata. These inorganic contaminant in drinking water is known to cause serious health problems when the maximum contaminant levels (MCL) exceed 1.5 mg/L. The aim of this study was to correlate the high fluoride content in the groundwater of the region to the geochemistry of the water...

We present a simple exact analytical solution, using the Weyl-Titchmarsh-Kodaira spectral theorem, for the spectral function of the one-dimensional diatomic molecule model consisting of two attractive delta function wells in the presence of a static external electric field. For sufficiently deep and far apart wells, this molecule supports both an even and an odd state, and the introduction of a...

Groundwater constitutes a critical component of our water resources. Widespread groundwater level declines have occurred in the USA over recent decades, including in regions not typically considered water stressed, such as areas of the Northwest and mid-Atlantic Coast. This loss of water storage reflects extraction rates that exceed natural recharge and capture. Here, we explore recent changes ...

In chis letter we integrate numerically the time dependent Schrodinger equation to investigate the use of a semi-infinite laser pulse to localize an electron in one of the wells of a double well quantum structure. Under certain conditions the system can be driven to emit stroxigly low frequency radiation.

We show that, under some very weak assumption of effective variation for the magnetic field, a periodic Schrödinger operator with magnetic wells on a noncompact Riemannian manifold M such that H(M, R) = 0 equipped with a properly disconnected, cocompact action of a finitely generated, discrete group of isometries has an arbitrarily large number of spectral gaps in the semi-classical limit.

We used a semi-classical model to describe carrier capture into and thermionic escape from GaInNAs/GaAs multiple quantum wells (MQWs) situated within the intrinsic region of a GaAs p-i-n junction. The results are used to explain photocurrent oscillations with applied bias observed in these structures, in terms of charge accumulation and resonance tunnelling.

The deeper a reservoir is, the smaller diameter the drilled full diameter cores have. It is difficult to conduct insitu stress experiments with conventional methods if the diameter of the full diameter cores is less than 6.0 cm, especially for cores abundant in natural fractures. In this paper, based on conventional Differential Strain Analysis (DSA) methods and wave velocity anisotropy methods...

This review covers a spectrum of optoelectronic properties of and uses for semi-insulating semiconductor heterostructures and thin films, including epilayers and quantum wells. Compensation by doping, implantation, and nonstoichiometric growth are described in terms of the properties of point defects and Fermi level stabilization and pinning. The principal optical and optoelectronic properties ...

in this paper to predict the critical conditions for onset of elastic-plastic wrinkling of flange of a two-layered circular blank during the deep-drawing process a closed-form semi-analytical elastic-plastic solution using tresca yield criterion alongwith deformation theory in plasticity with considernig the perfectly plastic behaviour of materials is presented. simplifying the presented soluti...

abstract aims: fluoride is one of the anions present in soil and water, and determining its level in drinking water is vital for preventing dental and bone diseases in societies. this research aimed to determine fluoride concentrations in drinking water sources of rural and urban areas of babol city, iran. instrument & methods: this descriptive cross-sectional study was conducted in babol city,...