Abstract: The invention discloses an eddy current testing system for nondestructive testing of a pipeline, which belongs to the field of nondestructive testing technology. The eddy current testing system includes a data processing unit, a first signal conditioning unit, a second signal conditioning unit, and a testing probe, wherein the testing probe comprises an excitation coil, a receiving coil, and a passive resonance coil; and the passive resonance coil is arranged between the excitation coil and the receiving coil.

Abstract: Provided are an organic compound and use thereof. Specifically, an organic compound, an OLED display panel, and an electronic device are provided. The organic compound has a structure shown in Formula (I); the OLED display panel comprises a first electrode, a second electrode, and an organic thin film layer provided between the first electrode and the second electrode; the organic thin film layer comprises a light-emitting layer; and a host material of the light-emitting layer comprises any one or a combination of at least two of the organic compounds; and the electronic device comprises the OLED display panel. The compound, when used as a host material of the light-emitting layer for the preparation of an OLED device, can reduce the driving voltage of the device, and improve the luminous efficacy and lifetime of the device.

Abstract: The invention discloses an NDT device for pipeline, belonging to the field of NDT, including a mobile carrier, which moves with fluid in pipeline or is moved by an actuator; a probe testing assembly, which includes a testing component installed on the mobile carrier and having a testing element in which testing probe is encapsulated; a data processing unit, a first signal conditioning unit and a second signal conditioning unit, wherein the testing probe includes an excitation coil, a receiving coil and a passive resonance coil between the excitation coil and the receiving coil. For the invention, no more magnetizing treatment device is needed for testing, so that the system volume is greatly reduced, thereby reducing the requirement of the testing system of the invention on the internal cleanliness of a pipeline, improving flexibility of equipment in the pipeline of the testing system, and greatly reducing the system cost.