in this paper a new low profile substrate integrated waveguide (siw) probe-fed h-plane horn antenna structure with improved gain is proposed. the proposed antenna consists of two waveguides including a rectangular and a taper one, in which both, first and third modes of the structure are simultaneously excited leading to a uniform field distribution along the radiating aperture of the antenna a...

in this study, nickel-phosphorus coating was prepared by electrodeposition technique on the 304 stainless steel substrate. the effects of current density, phosphorous acid concentration, time and ph on the phosphorous content was investigated using taguchi method. a uniform amorphous-nanocrystalline structure (ni-12%p) was obtained. sem, eds, tem and xrd were used in order to study the surface ...

Calix[4]arenes substituted at their wide rim by four aryl urea residues (1) form hydrogen-bonded dimers in apolar solvents. Replacement of one urea residue by an acetamido moiety leads to calix[4]arene derivatives (5) which form hydrogen-bonded tetramers under the same conditions. Both self-assembly processes occur independently. Therefore, molecules have been prepared in which a tetra-urea cal...

In this work, we prove that metric spaces with uniform normal structure have a kind of intersection property, which is equivalent to reflexivity in Banach spaces.