A waveguide whose sidewalls are replaced with densely arranged metallic posts has been proposed. This guide enables the easy realization of circuit patterns by the arrangement of metallic posts periodically in a parallel-plate waveguide or a grounded dielectric substrate. This type of waveguide is called the post-wall waveguide (PWW) (Hirokawa & Ando, 1998;Ando et al., 1998) or the substrate in...

By the reaction of TBA(4)H(4)[γ-SiW(10)O(36)] (TBA = tetra-n-butylammonium) with AgOAc (OAc = acetate) using dimethylphenylsilane as a reductant in acetone, a unique polyoxometalate containing a discrete octahedrally shaped [Ag(6)](4+) cluster, TBA(8)[Ag(6)(γ-H(2)SiW(10)O(36))(2)]·5H(2)O, could be synthesized, and the molecular structure was determined.

The title compound, (C(10)H(10)N(2))(2)[SiW(12)O(40)]·C(10)H(8)N(2)·6H(2)O or (4,4'-bipyH(2))(2)[SiW(12)O(40)].(4,4'-bipy)·6H(2)O (4,4'-bipy is 4,4'-bipyridine), was prepared under hydro-thermal conditions. The asymmetric unit contains a discrete Keggin-type [SiW(12)O(40)](4-) anion (located on a twofold axis), one 4,4'-bipy (located on a twofold axis), two (4,4'-bipyH(2))(2+) cations and six u...

A tin(II) tungstosilicate derivative K(11)H[Sn(4)(SiW(9)O(34))(2)]·25H(2)O with four sandwiched Sn(2+) cations was prepared by reaction of SnCl(2), KCl and Na(10)[α-SiW(9)O(34)]·xH(2)O. Visible-light photocatalytic H(2) evolution activity was observed with Pt nanoparticles as co-catalyst and methanol as sacrificial agent.

this paper describes the design of a 2x2 micro strip patch antenna array in the frequency of 9.5ghz for radar applications, using substrate integrated waveguide, siw, for feeding network. the micro strip patches are aperture-coupled with the feeding network of siw. the feeding network consisting of a perpendicular coax-to-siw transition and two y-junction power dividers. the antenna is simulate...

Evaluation and non-destructive identification of stress-induced cracks or failures in metals is a vital problem in many sensitive environments, including transportation (steel railway tracks, bridges, car wheels, etc.), power plants (steam generator tubing, etc.) and aerospace transportation (landing gear, aircraft fuselages, etc.). There are many traditional non-destructive detection and evalu...