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1

A Novel Design of Electromagnetic Bandgap Structure and its Effects on PI and SI

Yan Z., Wang Y., Che M., Han Y., Wang T., Rahman T.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 3b

72-77

EN

Power/Ground plane structure is the best configuration of the modern plane power distribution system. But in the high speed circuit, the resonant modes of the P/G planes can be excited when the high speed signal changes the reference plane. Thus it brings the ground bounce noise (GBN) and simultaneous switching noises (SSN) problems. This paper presents a novel electromagnetic bandgap structure which can suppress the high frequency and ultra-high frequency GBN and SSN by using a special S shape slender to connect the EBG unit. But the structure has a certain effect on the signal transmission features, while the simulation results show that loading the EBG structure in partial is not only able to restrain the GBN and SSN effectively, but also able to achieve good propagation characteristics.

PL

W artykule analizowane są szumy typu GBN I SSN. Zaprezxentoewano nową elektrlomagnetyczną strukturę pasmową umożliwiająca tłumienie tych szumów przy wysokich częstotliwościach.

2

Electron paramagnetic resonance investigations of CO adsorption on RuY zeolite

Blasco T., Bonneviot L., Li X. W., Che M., Chaquin P., Clerjaud B., Sojka Z.

Bulletin of the Polish Academy of Sciences. Chemistry

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2002

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Vol. 50, No. 2

267-279

EN

The adsorption of carbon monoxide onto ruthenium exchanged into NaY zeolite has been investigated by CW-EPR techniques using (13) C-enriched CO. A low spin eta (1){Ru(3cCO}(5) adduct with g = 2.065, g\\ = 1.987 and |A((99)Ru) = 1.3 mT, |A||(99)Ru) = 1.7 mT, |A_|(101 Ru) = 1.5 mT, A||(101)Ru) = 1.9 mT and |A|(13)C) = 6.0, |A|| |(13)C) = 6.8 mT has been identified. The magnetic parameters have been analyzed in terms of the molecular structure and spin density distribution. The results are consistent with an apical coordination of CO and the bonding established by the overlap between d(z)z2 and 5 sigma orbitals. The eta{RuIII (3c)CO}(5) adduct can be classified as a a metal-centred radical located in SIl'/SII sites. The spin density on Ru is equal to 0.6 and is confined mainly to the dz(2) orbital and 0.1 on carbon atom of the CO ligand.

3

Spectroscopic study of hydroxymethyl radicals produced on MoOx/SiO2 catalysts by interaction of methanol with UV-induced [Mo5+--O-] triplet state

Sojka Z., Che M.

Bulletin of the Polish Academy of Sciences. Chemistry

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2000

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Vol. 48, No. 4

313-324

EN

EPR along with MAS-NMR and QM spectroscopy have been used to investigate the structure and reactivity of hydroxymethyl radicals formed upon UV -irradiation of methanol adsorbed on MoOx /Si0(2) catalysts. The use of natural and 13C-enriched methanol allowed the authors to ascertain the 1 H superhyperfine and 13C hyperfine tensors. Based on the analysis of the magnetic parameters the structure of .CH2OH radical interacting with the catalysts has been determined: it is non-planar and the c- H bonds are stretched. The hydroxymethyl intermediates were found to reduce surface Mo(6+) centers and adsorbed O2 via an electroprotic mechanism involving electron transfer and release of the hydroxyl proton.