We visit the standard procedure for analyzing the optical spectrum of Ho doped tellurite glass has been studied. The glass was formed using a composition 79% Te O2 + 20% Li2 CO2 + 1% Ho O2. I density and refractive index were measured and used to calculate various physical properties such as, rare earth concentration, mean atomic volume, electric polarization, ionic radius, molar refractivity, ...

Studies have been aimed at the establishment of structure-activity relationships that define choline kinase inhibitory and antiproliferative activities of 40 bisquinolinium compounds. These derivatives have electron-releasing groups at position 4 of the quinolinium ring. It is found that the enzymatic inhibition is closely related to the size of the linker, the 3,3'-biphenyl moiety being the mo...

[1] This paper describes the estimation of propagation loss and its statistical properties on the basis of observations of radar sea clutter data. This problem is solved by first finding an ensemble of relevant refractivity model parameters, and each refractivity model is weighted according to its data likelihood function. A parabolic equation propagation model is used both in mapping from envi...

Radio occultation measurements using the Global Positioning System (GPS) and a receiver in low-Earth orbit (LEO) have recently been shown to provide accurate profiles of atmospheric refractivity, pressure, water vapor and temperature with high vertical resolution [e.g. Kursinski et al., 1996]. When a GPS transmitter and receiver pair are on opposite sides of the atmosphere, the radio signal pro...

The atmospheric propagation of GPS signals under multipath conditions and their detection are simulated. Using the multiple phase screen method C/A-code modulated L1 signals are propagated through a spherically symmetric refractivity field derived from a high-resolution radio sonde observation. The propagated signals are tracked by GPS receivers implemented in software and converted to refracti...

Assimilation into numerical weather models of the refractivity, Abel-retrieved from radio occultations, as the local refractivity at ray tangent point may result in large errors in the presence of strong horizontal gradients (atmospheric fronts, strong convection). To reduce these errors, other authors suggested modeling the Abel-retrieved refractivity as a nonlocal linear function of the 3D re...

The Quantitative Structure Activity Relationship (QSAR) study is performed over a set of 15, 4-alkyl/aryl-substituted 1- [benzofuran-2-yl-phenylmethyl]-1 H-triazoles derivatives. This study is based on the application of physicochemical parameters in QSAR. The parameters include (MR (molar refractivity), MW (molecular weight), Pc (parachor), St (surface tension), D (density), Ir (index of refra...

Using fumigation toxicity data of 11 natural and synthetic cyanohydrins to house fly (Musca domestica) and a stored-product pest, the lesser grain borer (Rhyzopertha dominica), the quantitative structure-activity relationships (QSAR) of cyanohydrins were examined by Oxford Molecular CAChe 3.2 and Microsoft Excel. This analysis used eight physicochemical parameters. Correlation between the LC(50...

In this work we have proposed a method based on neural networks to directly retrieve dry and wet refractivity and dry pressure profiles in troposphere (which in turn can be used to obtain temperature and humidity profiles) by using COSMIC GPS radio occultation (RO) data. To overcome the constraint of an independent knowledge of one atmospheric parameter at each GPS occultation, we trained diffe...

The terms bioaccumulation and bioconcentration refer to the uptake and build-up of chemicals that can occur in living organisms. Experimental measurement of bioconcentration is time-consuming and expensive, and is not feasible for a large number of chemicals of potential regulatory concern. A highly effective tool depending on a quantitative structure-property relationship (QSPR) can be utilize...