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To further develop the advantages of loading artificial material units, layout rules of unit cells were investigated and presented for the first time in this study. Based on the analysis of transmission characters of metamaterial unit cells, some tapered slot antennas loaded with different unit layouts were designed. The result comparison showed that after the layout optimisation, the operation frequency band with a gain above 10 dB increased by about 13% and the gain increased by 0.4–2.6 dB in the high frequency band. In addition, the sidelobe level of H‐plane also decreased by 0.7–4 dB at different frequency points.

A novel agarase-producing, non-endospore-forming marine bacterium, WH0801 T , was isolated from a fresh seaweed sample collected from the coast of Weihai, China. Preliminary characterization based on 16S rRNA gene sequence analysis showed that WH0801 T shared 96.1 % similarity with Agarivorans albus MKT 106 T , the type species of the genus Agarivorans. A polyphasic taxonomic study was conducted and confirmed the phylogenetic affiliation of strain WH0801 T to the genus Agarivorans. Isolate WH0801 T produces light-yellow-pigmented colonies; cells are Gram-stain-negative, straight or curved rods, which are motile with a single polar flagellum. Strain WH0801 T grew in 0.5-5 % NaCl, with optimum growth at 3 % NaCl, and its optimal pH and cultivation temperature were 8.4-8.6 and 28-32 6C, respectively. Data from biochemical tests, whole-cell fatty acid profiling, 16S rRNA gene sequence studies and DNA-DNA hybridization clearly indicated that isolate WH0801 T represented a novel species within the genus Agarivorans, for which the name Agarivorans gilvus sp. nov. is proposed. The type strain of Agarivorans gilvus sp. nov. is WH0801 T (5NRRL B-59247 T 5CGMCC 1.10131 T ).The genus Agarivorans was created by Kurahashi & Yokota (2004) to accommodate Gram-negative, strictly aerobic and agar-hydrolysing species. The genus is affiliated with the class Gammaproteobacteria and presently contains only the type species, Agarivorans albus. The Agarivorans albus strains studied by Kurahashi & Yokota were agarolytic and isolated from healthy marine organisms collected from the coast of the Kanto area in Japan. Many novel agardegrading bacterial species have been isolated from marine environments, where they occur as part of the indigenous flora. For example, Simiduia agarivorans, Aliagarivorans marinus, Aliagarivorans taiwanensis and Tamlana agarivorans were isolated from seawater samples (Shieh et al., 2008;Jean et al., 2009;Yoon et al., 2008); Psychromonas agarivorans, Microbulbifer agarilyticus and Marinimicrobium agarilyticum were found in marine sediment samples (Hosoya et al., 2009;Miyazaki et al., 2008;Lim et al., 2006); and Salegentibacter agarivorans was recovered from a species of sponge (Nedashkovskaya et al., 2006). The widespread occurrence of agar-degrading bacteria is probably best explained by their likely role in the carbon cycle involving the breakdown of agar and other sulfated galactans (Armisen & Galactas, 1987;Pomin, 2010), which form a significant component of the cell walls of red and green algae, the egg jelly coating of certain sea urchin species, and the outer tunics of ascidians (Pomin, 2010). We examined the diversity of agarolytic marine bacteria isolated from various marine samples such as seawater, sediment, seaweed and some marine animal samples that were taken from waters off various locations across coastal China. As a result of these efforts, we have already described one new genus, Gilvimarinus (Du et al., 2009). Here, we report the taxonomic characteristics of a novel species of the genus Agariv...

A multi-stable and electrically switchable cholesteric liquid crystal based on chiral ionic liquid is demonstrated. The cholesteric liquid crystal can be switched among the planar texture, focal conic texture, wide-band reflected state, and fingerprint texture by applying specific electric fields. Each of these four states exists stably for several hours without any obvious change observed at room temperature. The electro-optical properties and driving scheme of the cholesteric liquid crystal are also reported.

Gain of the conventional Vivaldi antenna (CVA) decreases at higher frequencies. A phase correcting lens (PCL) made up of nonresonant rectangular patch unit cells (UCs) is proposed to correct this problem. The layout of the UCs is specially designed taking into account the actual phase error at antenna aperture. The detailed analysis, design and discussion for the CVA with the proposed PCL are performed. The CVA, CVA with one‐layer PCL (CVA‐OPCL), and three‐layer PCL (CVA‐TPCL) are fabricated and measured. The measured results agree well with the simulated ones. The measured results show that the proposed CVA‐TPCL provides a gain variation of 5.75‐14.9 dBi in the wide operating range from 3.5 to 16 GHz, which leads to 1.1‐6.1 dBi gain enhancement than that of the CVA. In addition, the E‐plane half power beamwidths become narrowed significantly at higher frequencies. An average improvement of 4.54 dB is achieved in terms of the front‐to‐back ratio. The sidelobe levels, on average, are reduced by 4.1 dB and 2.8 dB for E‐plane and H‐plane, respectively.