Abstract: Provided is a preparation method for a lithium oxide material, including the following steps: mixing lithium carbonate, a carbon source and a dispersant according to a certain proportion, stirring and dispersing and carrying out wet grinding to obtain an intermediate solution; carrying out spray drying on the intermediate solution to obtain an intermediate, and sintering and pulverizing the intermediate under a protection atmosphere to obtain a lithium oxide material. The prepared lithium oxide is uniform in particle and high in purity. The technical process is simple, and suitable for large-scale industrial production. A prepared lithium oxide material is also provided.

Abstract: A multi-path audio amplification system that provides an output drive signal to electromechanical output transducers provides improved undistorted headroom, reduced path switching noise, and/or improved frequency response performance. Multiple signal amplification paths receive an audio input signal and have corresponding multiple output stages that have differing output impedances. A mode selector selects an active one of the multiple signal amplification paths is selected to supply the output drive signal. Outputs of the multiple output stages are coupled to the electromechanical transducer to provide the output drive signal and at least one of the multiple signal amplification paths includes an equalization filter for filtering the audio input signal to compensate for phase or gain differences referenced from the input to the outputs of the multiple output stages due to interaction between the differing output impedances and an impedance of the electromechanical transducer.

Abstract: A multi-path audio amplification system that provides an output drive signal to electromechanical output transducers provides improved undistorted headroom, reduced path switching noise, and/or improved frequency response performance. Multiple signal amplification paths receive an audio input signal and have corresponding multiple output stages that have differing output impedances. A mode selector selects an active one of the multiple signal amplification paths is selected to supply the output drive signal. Outputs of the multiple output stages are coupled to the electromechanical transducer to provide the output drive signal and at least one of the multiple signal amplification paths includes an equalization filter for filtering the audio input signal to compensate for phase or gain differences referenced from the input to the outputs of the multiple output stages due to interaction between the differing output impedances and an impedance of the electromechanical transducer.

Abstract: This invention relates to a method of preparing a compound type where at least one of R′ or R″ is a carbosyl group (I) by treating a compound of formula (II) with a Group I(a) or Group II(a) metal halide, with an aprotic dipolar amide-based solvent and water.

Abstract: This invention relates to a method of preparing a compound type where at least one of R′ or R″ is a carboxyl group (I) by treating a compound of formula (II) with a Group I(a) or Group II(a) metal halide, with an aprotic dipolar amide-based solvent and water.

Abstract: This invention relates to a method of preparing a compound type where at least one of R′ or R″ is a carboxyl group (I) by treating a compound of formula (II) with a Group I(a) or Group II(a) metal halide, with an aprotic dipolar amide-based solvent and water.