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Parametric studies on split S-shaped composite meta atom for X-band communication

Hasan M. M., Faruque M. R. I., Islam M. T.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2017

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Vol. 65, nr 4

533--539

EN

The aim of this paper is to describe a split S-shaped composite meta atom which shows double negative characteristics at resonance frequency. The proposed meta-atom structure exhibits an almost 3.70 GHz bandwidth when the operating frequency from 8 to 14 GHz (X-band). In this study, the ring width, split width, size of substrate material, and the substrate material itself are varying to investigate their effect on the resonance frequencies. Metal strips of the outer resonator are the splits and the inner ring resonator is designed in a way that it forms a split S-shaped structure on the epoxy resin fibre (FR-4) substrate material. The CST Microwave Studio electromagnetic simulator software was used for the design and simulation purposes, and an Agilent N5227A vector network analyser was used for practical measurements.

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Comparing guided modal properties of surface waves along single- and double-negative indexed slab waveguides

Kim K. Y., Cho Y. K.

Opto-Electronics Review

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2010

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Vol. 18, No. 4

388-393

EN

The guided dispersion characteristics of the fundamental symmetric and asymmetric modes of surface waves along single- and double-negative indexed slab waveguides are investigated, and a comparative analysis made when varying the single- and double-negative permittivity and permeability. While the values of the permittivity and permeability of the slab region are varied to obtain a salient picture of the guided dispersion characteristics, identical absolute product values are used for both slab cases to facilitate a reasonable comparison. In particular, in common ranges where guided mode solutions coexist for both the single- and double-negative indexed slabs, the guided mode characteristics are similar with a lower normalized frequency regime, indicating that the sign of the material parameters has a negligible effect, whereas the characteristics become quite different as the normalized frequency increases. Some other anomalous guided dispersion properties are also discussed and compared with previously reported results.

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Synthesis and Characterization of 1,2-Dinitroguanidine (DNG) and its Derivatives*)

Latypov N. V., Johansson M., Wahlström L. N., Ek S., Eldsäter C., Goede P.

Central European Journal of Energetic Materials

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2007

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Vol. 4, nr 1-2

3-16

EN

1,2-Dinitroguanidine (DNG), (1), is a novel explosive with reported high performance and moderate sensitivity [1, 2]. Synthesis of DNG and its salts has recently been reported [3]. X-ray studies on the crystal structure of DNG and its thermal stability can also be found in the literature [4, 5]. In this paper, complementary studies on the synthesis, reactivity and thermal characteristics of this compound and some of its derivatives are presented.