Abstract: Embodiments of the present disclosure relate to a permission setting method and apparatus, a device, and a medium. The method includes: displaying a permission customization control, in response to a trigger operation on a permission setting object of task information, the permission setting object including a first information object and/or a second information object, the second information object being subordinate to the first information object; displaying a permission editing interface, in response to a trigger operation on the permission customization control, and receiving customization permission information via the permission editing interface; and displaying the customization permission information corresponding to the permission setting object. Therefore, a hierarchy structure based on the task information satisfies a setting need for content-based permission customization, and improves a permission management efficiency.

Abstract: The present invention provides a process for producing lower olefins by catalytic cracking a feedstock comprising an olefins-enriched mixture containing C4 or higher olefins and optionally an organic oxygenate compound. The technical problem mainly addressed in the present invention is to overcome the defects presented in the prior art including low yield and selectivity of lower olefins as the target products, and short regeneration period of catalyst.

Abstract: The present invention provides a process for producing lower olefins by catalytic cracking a feedstock comprising an olefins-enriched mixture containing C4 or higher olefins and optionally an organic oxygenate compound. The technical problem mainly addressed in the present invention is to overcome the defects presented in the prior art including low yield and selectivity of lower olefins as the target products, and short regeneration period of catalyst.