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A novel miniature Wilkinson power divider (WPD) design is presented. This is achieved by substituting the quarter-wavelength transmission-lines constituting the WPD with an equivalent pair of parallel transmission-lines (PPTLs) that effectively reduce the circuit size of the WPD by 43% compared with a conventional design whose ground-plane is defected. Particle swarm optimization (PSO) technique is used to achieve size reduction. Meandering the transmission-lines further reduce the WPD size by 22%. The proposed WPD has overall dimensions of 9.38 × 11.51 mm2 or 0.11 λg × 0.14 λg, which is compatible with the requirements imposed by portable personal wireless systems. Coupling between the parallel transmission-lines is shown to extend the operational bandwidth of the power divider to 3.2 GHz (0.8–4 GHz) for a return-loss better than 10 dB. [ABSTRACT FROM AUTHOR]

This paper presents a new ultra‐wideband (UWB) antenna system with circular polarization (CP). The antenna is a coplanar waveguide (CPW) feed structure with a modified inverted L‐shaped radiating patch. A single‐layer non‐uniform frequency selective surface (FSS) composed of rectangular conductive patches is designed and used with the CP antenna to improve the CP characteristics and the gain of the antenna. According to the measured results, the 10 dB return‐loss bandwidth of the antenna with the FSS extends from 3.7 to 11.1 GHz. The 3‐dB measured axial ratio (AR) bandwidth is 58.15%, covering 5 to 9.1 GHz, and the measured peak gain is 4–9.4 dBi, showing an increase of about 3 dBi compared to the antenna without the FSS. Key Points: A new UWB CPW‐fed slot antenna capable of circular polarization operation is presented for WLAN applicationA single‐layer reflecting FSS is designed to improve the antenna gain by 3 dBi and extending axial ratio bandwidth [ABSTRACT FROM AUTHOR]

Extraction of ferulic acid from sugar beet pulp was carried out using alkaline hydrolysis (NaOH) method and the effects of parameters on extraction were assessed. HPLC method and FT-IR spectrum of precipitate in purification method performed to proved that the isolated compound was ferulic acid. Finally the antioxidant activity of isolated ferulic acid was evaluated by ABTS.+ method. Time, temperature and NaOH concentration were the most significant factors influencing ferulic acid extracton and severe alkali concentration has a negative dissociation effect on the ferulic acid content for all temperature/time conditions. The optimal conditions for extraction time, temperature and NaOH concentration were (12 hours, 41°C, and 2 M) respectively. Antioxidant capacity for isolated and pure ferulic acid was 0.39±0.01 and 0.55±0.01 respectively. It's showed that sugar beet pulp is potent source of ferulic acid that can be extracted and use as an antioxidant. [ABSTRACT FROM AUTHOR]

A total of 72124 fertility records was used to estimate the genetic and phenotypic trend of fertility traits in Iranian Holstein cow from 1981 to 2007. Fertility traits in this study were: days from calving to first service (DFS), number of insemination per conception (INS), days open (DO), interval between first and last insemination (IFL), calving interval (CI) and success to first insemination (SF). The overall genetic trend in fertility traits was as desired and statistically significant. Mean breeding value of SF increase by 0.00067 percent per year. The annual genetic trends for INS, DFS, IFL, CI and DO were -0.0029 number/year, - 0.062 days/year, -0.041 days/year, -0.23 days/year and -0.24 days/year, respectively. Phenotypes trends for fertility traits were unfavorable except for DFS and DO. Phenotypic trends in IFL, INS and SF were as undesirable positive. Phenotypically DO and CI did not change over the time period. Phenotypically IFL has increased 1.6 days/year and DFS has decreased 1.6 days/year. The annual phenotypic trends for INS and SF were 0.04 and -0.018, respectively. [ABSTRACT FROM AUTHOR]