A polarimetric radar covariance matrix model is described to study the behavior of the co-to-cross covariances in precipitation. The 2 3 2 propagation matrix with attenuation, differential attenuation, and differential phase is coupled to the backscatter matrix leading to a propagation-modified covariance matrix model. System polarization errors are included in this model as well. This model is...

Nonuniform beam filling may also cause significant perturbations of the radial profile of differential phase ΦDP (Ryzhkov and Zrnic 1998; Gosset 2004). Such perturbations of ΦDP result in spurious values of its radial derivative, specific differential phase KDP, and strong biases in the KDP-based estimates of rain rate. These adverse effects are commonly manifested as the appearance of negative...

The precursors of SnO2 or In2O3/SnO2 nanocrystlline powders have been prepared by the sol-precipitation method. The precursors were calcined at different temperatures to prepare SnO2 or In2O3/SnO2 nanocrystalline powders with different particle sizes. The nanocrystallites were examined by differential thermal analysis (DTA), X-ray diffraction (XRD) and transmission electron microscopy (TEM). An...

Abstract: materials can be fabricated by sintering of W-Cu composite powders. In this research W-20%wt Cu composite powderswas synthesized via a co-precipitation method. Precipitate obtained from a mixture of copper nitrate and ammoniumparatungstate (APT) in distilled water contained W-Cu compounds. This precipitate was washed, dried and calcinedat 550 of dried precipitate powder was determined...

This work is related to the characterization of nanometrics materials ?MnMoO4-?CoMoO4 system, prepared by co-precipitation and sol-gel routes from corresponding metal salts. The structural, morphological colorimetric characteristics obtained powders were studied using thermogravimetric differential thermal analysis (TGA-DTA), X-ray diffraction (XRD), infrared Raman spectroscopy, scanning electr...

In this study, Flake-like magnesium hydroxide (Mg(OH)2) and cubic-like aluminum hydroxide (Al(OH)3) nanostructures were synthesized via a simple co-precipitation method at relatively low temperature. Chemical properties and surface morphology of the magnesium hydroxide and aluminum hydroxide were characterized by X-ray diffraction analysis (XRD), scanning electron microscopy image (SEM), transm...

When an aluminum alloy is solution annealed and afterwards cooled too slowly, an exothermal precipitation reaction occurs. With increasing cooling rate, the precipitation heat decreases. Since the precipitation reaction is relatively fast, a fast cooling rate on the differential scanning calorimeter (DSC) is essential to obtain the critical cooling rate which is the minimum cooling rate at whic...

A series of Ce1 ́xCoxO2 ́y precursors were prepared by homogeneous precipitation using urea as a precipitant. The Co/CeO2 catalysts obtained from the Ce1 ́xCoxO2 ́y precursors were used for the steam reforming of ethanol to produce hydrogen. Co ions could enter the CeO2 lattices to form Ce1 ́xCoxO2 ́y mixed oxides at x ď 0.2 using the homogeneous precipitation (hp) method. CeO2 was an excellent suppo...

Hamsters are increasingly used for comparative study of cholesterol metabolism (1). To assess the validity of differential precipitation with Mg2 4-phosphotungstate for quantification of plasma high-density-lipoprotein cholesterol (HDLC), we did a method-comparison with ultracentrifugal flotation. The precipitating reagent, 0.55 mmolJL phosphotungstic acid and 25 mmol/L magnesium chloride, was ...

The removal mechanisms of silicate using an aluminum hydroxide co-precipitation process was investigated and compared with an adsorption process, in order to establish an effective and validated method for silicate removal from wastewater. Adsorption isotherms, XRD and FT-IR analyses showed that silicate uptake occurred by adsorption to boehmite for initial Si/Al molar ratios smaller than two, ...