A novel compact broadband 5–35 GHz balun

Abstract

In this study, we investigated the yield and physicochemical properties of the high molecular weight extracellular polymeric substance (HMW–EPS) produced by Halomonas sp. strain TG39 when grown on different types and ratios of substrates. Glucose (1% w/v) and a peptone/yeast extract ratio of 5.1 (0.6% w/v final concentration) yielded an EPS fraction (HMW‐glucose) exhibiting the highest anionic activity (20.5) and specific emulsifying activity (EI24 = 100%) compared to EPS produced by cells grown on mannitol, sucrose, malt extract or no carbon source. The HMW–EPS fractions were capable of binding ≈255–464 mg of methylene blue (MB) per gram of EPS, which represents the highest reported binding of MB by a bacterial EPS. A comparative evaluation of these properties to those of commercial hydrocolloids indicated that the combined effect of protein and anionic residues of the HMW–EPS contributed to its ability to emulsify n‐hexadecane. Liquid chromatography revealed the HMW‐glucose EPS to be a heterogeneous polymer with a polydispersity index of 1.8. This work presents evidence of a correlation between the anionic nature and protein content of bacterial EPS with its emulsifying qualities, and identifies EPS produced by strain TG39 as a high MB‐binding bacterial sorbant with potential biotechnological application. Biotechnol. Bioeng. 2009;103: 207–216. © 2008 Wiley Periodicals, Inc.

Investigation of a compact and broadband balun

“…One cautions, for example, that polarization-based diversity schemes may be penalized by a 3 dB power loss, whereas eight and nine suggest that cross-polarization discrimination levels and polarization-specific path-losses may neutralize expected diversity gains. Other data sets do not confirm these limitations [1][2][3][4][5][8][9][10], and these pessimistic voices must be understood in their specific contexts. MIMO capacity measurements depends directly on the channel involved: some channels are well-suited to exploiting polarization, whereas others are not.…”

“…Generally, these balun topologies are based on the following types: the first one is the Marchand baluns [1][2][3][4] or coupled line baluns [5][6][7]; the second one is the slotline-based baluns [8 -11]; the third group is the power divider-based ones [12][13][14][15][16]; and the last one is branch-line baluns [17,18]. They are extensively implemented in planar versions [2-5, 7, 9, 12, 13, 15-18], multiplayer structures [6,8,10,11,14,19], or LTCC [20] as well as 3D configurations [21,22]. Among them, baluns with planar versions may be one of the most attractive because of their planar structures and easy integrations with other microwave circuits.…”