Abstract: A compound is provided as having a structure of Formula I: where X1 and X2 are each independently a nitrogen atom or a C—R group, C is a carbon atom, R is a hydrogen atom, a deuterium atom, a halogen atom, or a cyano group, CR, and at least one of X1 and X2 is N; L1, L2, and L3 are each independently a single bond, a substituted or unsubstituted aryl group, or substituted or unsubstituted aryl heteroaryl group; and Ar1, Ar2 are each independently a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group.

Abstract: A method for displaying content includes: displaying a first interface, where first video content is played by a video player on the first interface; and displaying first target content by the video player, in response to a first content stream switching on the first video content, where the first target content is non-video content and is associated with the first video content.

Abstract: Techniques are described for assigning users to swarms based on skill and generating recommendations for increasing skill proficiency. In some implementations, a request specifying a set of requirements for completing a task includes at least one required skill, optionally in combination with a required minimum proficiency value(s). Metrics can be generated based on statistical analysis of instances in which a task is at least one of: (i) assigned to a user who is not associated with a required skill, (ii) assigned to a user whose proficiency value is below a required minimum proficiency value, or (iii) assigned after a delay due to unavailability of a user who is associated with a required skill. The computer system can identify a first skill for improving the metrics, identify a user for becoming associated with the first skill, and send a notification recommending an online learning resource relating to the first skill.

Abstract: A performance testing device for acid fracturing fluid includes: two semiterete rock core holders, the flat face sides of the two semiterete rock core holders being arranged opposite to each other; the two semicircle sides of the two semiterete rock core holders being provided with a rotation member which is opened with a first groove; the two semiterete rock core holders being able to rotate about a first rotation axis formed corporately by the two rotation members; a pressure applying shell having a recessed portion that matches with the curved face side, the recessed portion being able to cooperate with the curved face side, the pressure applying shell being able to apply a pressure to the two rock core holders to bring the two flat face sides thereof together.

Abstract: A performance testing device for acid fracturing fluid includes: two semiterete rock core holders, the flat face sides of the two semiterete rock core holders being arranged opposite to each other; the two semicircle sides of the two semiterete rock core holders being provided with a rotation member which is opened with a first groove; the two semiterete rock core holders being able to rotate about a first rotation axis formed corporately by the two rotation members; a pressure applying shell having a recessed portion that matches with the curved face side, the recessed portion being able to cooperate with the curved face side, the pressure applying shell being able to apply a pressure to the two rock core holders to bring the two flat face sides thereof together.