Abstract: A facility providing securely for a multi-tiered server-implemented application is described. The facility receives in a back-end application service a request from a front-end application service. The request includes both (1) a first security token obtained by a client that called the front-end application service, which identifies as its audience the front-end application service, and (2) a second security token obtained by the front-end service identifying the back-end service as its audience. The facility validates the first and second security tokens. Where the first and second security tokens are both successfully validated, the facility performs the received request in the back-end application service. Where the first and second security tokens are not both successfully validated, the facility returns an error.

Abstract: A bowl mill for a coal pulverizer with an air mill for primary entry of air, comprising a substantially closed separator body (2) having a central axis; and a bowl-like grinding table (3) mounted on a shaft (4) rotatable about said central axis, cooperating with a plurality of grinding rolls (6). The airmill is provided with multiple entry openings (17?,17?; 18?, 18?; 21, 25) on the outer wall of the air mill for multiple entry of hot primary air from the inlets, resulting in better uniformity in air flow around the air mil section and for minimizing formation of eddies and vortices. As a variation of the multiple entry double entry openings can be arranged for entry of hot primary air.

Abstract: A bowl mill for a coal pulverizer with an air mill for primary entry of air, comprising a substantially closed separator body (2) having a central axis; and a bowl-like grinding table (3) mounted on a shaft (4) rotatable about said central axis, cooperating with a plurality of grinding rolls (6). The airmill is provided with multiple entry openings (17′, 17″; 18′, 18″; 21, 25) on the outer wall of the air mill for multiple entry of hot primary air from the inlets, resulting in better uniformity in air flow around the air mill section and for minimizing formation of eddies and vortices As a variation of the multiple entry double entry openings can be arranged for entry of hot primary air.