The new tellurite glasses with chemical composition 64TeO2-15CdO-(20-x) ZnO-xLi2O-1V2O5 (x= 0, 5, 10, 15 and 20 mol %) were synthesized by traditional melt quench hardening method. glass samples showed broad humps of typical amorphous phase in the X- ray diffraction patterns. physical properties such as density (ρ), molar volume (Vm), oxygen packing (OPD), refractive index (n), refractivity (Rm...

Radio wave propagation on low-altitude paths over the ocean above 2 GHz is significantly affected by negative refractivity gradients in the atmospheric surface layer (ASL) which form what is often referred to as an evaporation duct (ED). Refractivity from clutter (RFC) is an inversion approach for estimation of the refractivity profile from radar clutter, and RFC-ED refers to its implementation...

COVID-19, which has spread all over the world and was declared as a pandemic, is new disease caused by coronavirus family. There no medicine yet to prevent or end this pandemic. Even if existing drugs are used alleviate not enough. Therefore, combinations of their analogs being studied. Vaccines produced for COVID-19 may be effective variants virus. it necessary find soon possible. Topological ...

InSAR signal delays due to the varying atmospheric refractivity are a potential data source to improve weather models [1]. Especially with the launch of the new Sentinel-1 satellites, which increases data coverage, latency and accessibility, it may become possible to operationalize the assimilation of differential integrated refractivity (DIR) values in numerical weather models. Although studie...

The primary scientific objective of this research is to develop GPS sounding techniques for ground based atmospheric refractivity sensing. Atmospheric profiling with GPS from space has been demonstrated (e.g. Rocken et al., 1997). Ground based receivers have been used to determine integrated atmospheric water vapor above a site, but profiling techniques with ground-based GPS observations are st...

TeO2-ZnO-La2O3 (TZL) ternary glasses were investigated in order to manufacture step-index optical fibers with low losses the near- and mid-infrared ranges superior mechanical properties. To identify appropriate TZL glass compositions for manufacturing, whole vitreous domain of diagram was explored by characterizing bulk samples from thermal point view. Investigations focused on understanding ho...

Taraba state broadcasting station (TSBS) is situated in Jalingo with coordinates (8º 56N 11º 55E) transmission frequency of 90.6 MHz covering a distance 250 km and operates for up to fifteen hours day. The signal strength TSBS was taken as function some variables which are temperature, refractivity, humidity, solar radiance other ionospheric factors cognizance. measured values shows negative co...

Many previous studies have demonstrated that GPS radio occultation (RO) data have positive impacts on global operational numerical weather prediction as well as the forecasting of severe weather events such as atmospheric rivers and hurricanes. The assimilation of GPS RO data can be performed with different observation operators, including: local refractivity, local bending angle, nonlocal exce...