Different ratios and sizes of Ba2F3Cl (BaFxCl2-x, x=1.5) nanorods and nanowires and orthorhombic BaF2 (BaFxCl2-x, x=2) nanorods were prepared by using a liquid-solid-solution approach at 160 approximately 180 degrees C. The processes and results of the experiments conducted to prepare monodisperse Ba2F3Cl nanorods and nanowires showed that the specific surface area increased as the initial concentrations were multiplied. Based on this fact, a mechanism for the nucleation and growth processes of these nanocrystals that have a variety of enlarged sizes was substantiated in view of the surface chemical thermodynamics (SCT). In this SCT mechanism, the specific surface energy takes into account both the surfactant oleic acid and the nanocrystal surface, and is dominated by the chemical potential of the adsorbate.

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Using 3-Dimensional (3D) sound sources as secondary sources to 2-Dimensional (2D) sound field reproduction, it is termed 2.5-Dimensional (2.5D) sound field reproduction which is currently drawing broad interest in acoustic signal processing. In this paper we propose a method to reproduce a 2D sound field, using a circular array of 3D High Order (HO) loudspeakers, which provides a mode matching solution based on 3D wave field translation. Using the spherical addition theorem, we first obtain a spherical harmonics representation of a 2D sound field reproduced by an array of HO loudspeakers. Then, the corresponding relationship between the reproduced sound field and the desired sound field is established by spherical/cylindrical harmonic expansions. Finally, the modal weights of HO loudspeakers are designed by using a least squares method. Simulation results show that the proposed method extends the reproduction region and significantly reduces the required minimum number of loudspeakers over the other referenced methods.

Object-based audio techniques have become common since they provide the flexibility for personalized rendering. In this paper a multi-stage encoding scheme for multiple audio objects is proposed. The scheme is based on intra-object sparsity. In the encoding phase the dominant Time Frequency (TF) instants of all active object signals are extracted and divided into several stages to form the multistage observation signals for transmission. In the decoding phase the preserved TF instants are recovered via Compressed Sensing (CS) technique, and further used for reconstructing the audio objects. The evaluations validated that the proposed encoding scheme can achieve scalable transmission while maintaining perceptual quality of each audio object.