Abstract: Provided are a control circuit (100), a circuit board assembly, and a battery (200) parallel system. The control circuit (100) is disposed between a battery (200) and a busbar (300), and the control circuit (100) comprises an acquisition unit (1), a control unit (2), and a current-limiting circuit (3). The control unit (2) is used to start timing when the current of a positive electrode of the battery (200) is greater than a preset threshold, and after the duration of the voltage of the positive electrode of the battery (200) greater than a first preset threshold is greater than a preset time, reduces the current of the positive electrode of the battery (200) by means of controlling the current-limiting circuit (3), until the current of the positive electrode of the battery (200) is less than or equal to the preset threshold.

Abstract: Disclosed is a method for measuring surface tension based on an axisymmetric droplet contour curve. The method comprises: photographing a suspended droplet image, and extracting a droplet contour curve; selecting a measurement point on the droplet contour curve; and calculating the surface tension of a liquid using the following formula ? = ?? ? ? gV + P ? ? ? ? ? R 2 2 ? ? ? ? R ? ? sin ? ( ? ) , wherein ? is the surface tension of the liquid, ?? is the density difference between the liquid and the atmosphere, g is the local gravitational acceleration, P is the pressure at the cross section of the droplet cut from a horizontal plane of the measurement point, R is the radius of a circular surface formed by cutting the droplet, ? is the inclination angle between the tangent line of the measurement point on the droplet and the horizontal plane, and V is the droplet volume at the lower part of the cross section of the droplet.

Abstract: Embodiments of this application disclose a camera assembly and a terminal device. The camera assembly includes a transmission mechanism, a base, a rear housing, and a guide ring. A first end of the base is connected to the transmission mechanism, and a second end of the base is hinged to the rear housing. The rear housing has space for accommodating a camera, and at least two guide slots are disposed on the rear housing. A fixing part and a guide post are disposed on the guide ring, the fixing part is configured to fasten the guide ring to the terminal device, and the guide post adapts to the at least two guide slots. In a process in which the rear housing protrudes out of the terminal device, the guide post of the guide ring moves on the at least two guide slots of the rear housing, so that a movement direction of the rear housing is offset by a preset included angle. Therefore, a shooting angle of the camera disposed in the rear housing also changes, and the shooting angle of the camera is adjusted.

Abstract: A device for vacuum dehydration of a low-volatile liquid, the device including: a vacuum tank, a condenser, a water discharging device, and a pump for extraction of the gas-liquid mixture. The vacuum tank includes: a liquid inlet, an outlet, a mixed space of a gas-liquid mixture, and a gas-phase space. The condenser is disposed in the gas-phase space of the vacuum tank. The outlet of the vacuum tank is connected to the pump. The gas-phase space is formed above the mixed space and communicates with the mixed space. The gas-liquid mixture is discharged out of the vacuum tank via the outlet thereof by the pump. Water vapor in the gas-phase space is condensed and discharged out of the vacuum tank via the water discharging device.

Abstract: This invention provides a light-emitting diode (LED). The LED is electrically connected with a circuit board. The LED includes a light-emitting chip, an encapsulating element, a lead, and a heat insulating element. The encapsulating element encapsulates the light-emitting chip. The lead is coupled with the light-emitting chip and the circuit board. The lead and the encapsulating element form a first connecting place. The lead and the circuit board form a second connecting place. The heat insulating element is disposed between the first connecting place and the second connecting place.

Abstract: This invention provides a light-emitting diode (LED). The LED is electrically connected with a circuit board. The LED includes a light-emitting chip, an encapsulating element, a lead, and a heat insulating element. The encapsulating element encapsulates the light-emitting chip. The lead is coupled with the light-emitting chip and the circuit board. The lead and the encapsulating element form a first connecting place. The lead and the circuit board form a second connecting place. The heat insulating element is disposed between the first connecting place and the second connecting place.