A Wideband Printed Directional Antenna Array with Impedance Regulating Load

We proposed a broadband directional antenna array working at mobile communication frequency band, which achieves a relative bandwidth of 50.7%. This binary antenna array is fed by two branches of the balanced microstrip. To enhance the antenna bandwidth, we introduced a section of loading metal strip. The antenna prototype has a S11 lower than −10 dB within the 1.5 GHz to 2.52 GHz frequency band, particularly from 2.01 GHz to 2.50 GHz, the S11 is lower than −15 dB. The gain varies with relatively small variation within the working band, which is 5.4 dBi to 8.7 dBi

High Curie temperature and high hole mobility in diluted magnetic semiconductors (B, Mn)X (X = N, P, As, Sb)

Doping nonmagnetic semiconductors with magnetic impurities is a feasible way to obtain diluted magnetic semiconductors (DMSs). It is generally accepted that for the most extensively studied DMS, (Ga, Mn)As, its highest Curie temperature T$_{\text{C}}$ was achieved at 200 K with a Mn concentration of approximately 16% in experiments. A recent experiment reported record-breaking high electron and hole mobilities in the semiconductor BAs [Science 377, 437 (2022)]. Since BAs shares the same zinc-blende structure with GaAs, here we predict four DMSs (B, Mn)X (X = N, P, As, Sb) by density functional theory calculations. Our results indicate that a significantly higher T$_{\text{C}}$ in the range of 254 K to 300 K for (B, Mn)As with a Mn concentration of around 15.6%, and even higher T$_{\text{C}}$ values above the room temperature for (B, Mn)N and (B, Mn)P with a Mn concentration exceeding 12.5%. Furthermore, we have predicted a large hole mobility of 1561 cm$^{\text{2}}$V$^{\text{-1}}$s$^{\text{-1}}$ at 300 K for (B, Mn)As with a Mn concentration of about 3.7%, which is three orders of magnitude larger than the hole mobility of 4 cm$^{\text{2}}$V$^{\text{-1}}$s$^{\text{-1}}$ at 300 K observed in the experiment for (Ga, Mn)As. Our findings predict the emergence of a new family of DMS, (B, Mn)X, and are expected to stimulate both experimental and theoretical studies of the DMS with high T$_{\text{C}}$ and high mobilities

2-(2H-Tetra­zol-5-yl)pyridinium nitrate

In the cation of the title compound, C6H6N5 +·NO3 −, the dihedral angle between the pyridinium and tetra­zole rings is 8.2 (2)°. The constituent ions of the compound are linked via N—H⋯O hydrogen bonds, forming helical chains running along the b axis. C—H⋯N and C—H⋯O hydrogen bonds are also observed