Embodiments of the invention provide systems and methods for water treatment and/or desalination.

A method and an apparatus for removing dust in a sound outlet hole of a loudspeaker and a terminal device are disclosed. The method includes reading a prestored audio frequency for removing dust; and playing the audio file for removing dust. When the loudspeaker plays the audio file for removing dust, a wind speed in the sound outlet hole is at a maximum.

A device with external diaphragm for acoustic cleaning and air purification is provided. The device comprises a housing with a first opening at a top for receiving one or more acoustic wave generating devices each with a diaphragm attached to a coil; and one or more external diaphragm each covering and sealing the diaphragm attached to the coil to facilitated in protecting the acoustic wave generating device as impurities or materials deposit and accumulate on the external diaphragm instead of the diaphragm of the acoustic wave generating device, and easy cleaning as only the external diaphragm needs to be cleaned, which also avoids damage to the diaphragm of the acoustic wave generating device during cleaning.

The invention discloses a pipeline descaling and rock stratum fracturing device based on electro-hydraulic pulse shock waves, comprising a ground low-voltage control device, a transmission cable and an electro-hydraulic pulse shock wave transmitter. The invention generates available high-strength shock waves with repetition frequency to bombard a specific position of the pipeline or rock stratum so as to achieve the effect of pipeline descaling and rock stratum fracturing; the breakdown field strength of the liquid gap can be effectively reduced to improve the conversion efficiency of the electrical energy to the mechanical energy of the electro-hydraulic pulse shock wave so as to obtain a high-strength electro-hydraulic pulse shock wave; the transmitting cavity adopts a parabolic focusing cavity, and through refraction and reflection of the rotating parabolic cavity, the shock wave is focused in a preset direction and radiates outwards to act on the pipeline dirt or rock stratum while ensuring that the shock wave has no longitudinal component and does not will not damage the liquid within the pipeline and the pipeline sheath, so that the effect of pipeline descaling or rock stratum fracturing is improved after focusing. The invention has the advantages of effectively removing the pipeline dirt, fracturing the rock stratum and improving the permeability as well as high reliability, environmental friendliness and low cost.

A method and system for cleaning a field emission cathode device, the field emission cathode device including a substrate having a field emission layer engaged therewith, includes engaging the field emission cathode device with a vibration device such that the substrate is disposed above the field emission layer. The field emission cathode device is then vibrated with the vibration device in an X, Y, or Z direction at a predetermined frequency and at a predetermined amplitude for a predetermined time duration so as to clean the field emission cathode device by dislodging non-embedded particles from the field emission layer.

Removing unfused powder from internal passages of an additive-manufacture part includes attaching piezoelectric transducers to a plurality of locations on an exterior of the part. The part is vibrated by driving the piezoelectric transducers at varying amplitudes and frequencies. An amount of the unfused powder that exits the part is monitored.

Various embodiments may include a method for removing filling material from a cavity in a manufactured component with a connection from the cavity opening to surroundings of the component, the method comprising: holding the component in a movable mounting; moving the component and at the same time removing the filling material through the connection opening; and executing a computer program with a processor, wherein the computer program instructs the processor to: analyze geometry data of the component including the connection opening; and calculate a necessary positioning of the component, based on the geometry data and gravitational force; and direct the movable mounting through a sequence of movements for moving the component in space to spill the filling material from the cavity through the connection opening out of the component.

Disclosed is an acoustic drainage structure and an electronic device. The acoustic drainage structure includes a housing and an acoustic assembly. The housing is provided with an accommodating cavity and a first sound-pickup hole communicated with the accommodating cavity. The acoustic assembly includes a sound-pickup module provided in the accommodating cavity and a sound-generating unit provided in the accommodating cavity. The sound-pickup module includes a sound-pickup unit, a connector and a breathable waterproof membrane, the breathable waterproof membrane is provided at a cavity wall of the accommodating cavity, the connector is connected to the breathable waterproof membrane and the sound-pickup unit, and the connector is provided with a second sound-pickup hole. The breathable waterproof membrane covers the first sound-pickup hole and the second sound-pickup hole, and the breathable waterproof membrane, and a hole wall of the second sound-pickup hole and the sound-pickup unit are enclosed to form a sound-pickup cavity.

Methods and systems for cleaning devices holding fluid which use a system such as a transducer assembly including at least one pair of protrusions acting as point-like pressure sources or at least one substantially circular protrusion acting as a substantially circular point-like pressure source, coupled to an outer surface of the device to be cleaned.

A self-cleaning sensor guard is provided. The guard may comprise an acoustic duster housing, a dust guard, a proximity sensor, a phase-enabled controller, and an ultrasonic cleaning source. The dust guard may be positioned to impede passage of ambient particulates into the acoustic duster housing. The proximity sensor may be positioned to generate a dust detection signal that is indicative of the presence of particulates on the dust guard. The ultrasonic cleaning source may be oriented to direct multi-phase and multi-frequency ultrasonic cleaning waves towards the dust guard. The phase-enabled controller may be programmed to drive the ultrasonic cleaning source, at least partially in response to the dust detection signal, by superimposing a first acoustic signal and a second acoustic signal.