‘Tracers’ are bullets that emit light at the backside so that the shooter can see the trajectory of their flight. These light-emitting bullets allow snipers to hit targets faster and more accurately. Conventional tracers are all combustion type which use the heat generated upon ignition. However, the conventional tracer has a fire risk at the impact site due to the residual flame and has a by-product that can contaminate the inside of the gun and lead to firearm failure. To resolve these problems, it is necessary to develop non-combustion-type tracers that can convert heat to luminance, so-called ‘thermoluminescence (TL)’. Here, we highly improve the thermoluminescence properties of MgB4O7 through co-doping of Dy3++Ce3+ and Dy3++Na+. The presence of doping materials (Dy3+, Ce3+, Na+) was confirmed by XPS (X-ray photoelectron spectroscopy). The as-synthesized co-doped MgB4O7 was irradiated with a specific radiation dose and heated to 500 °C under dark conditions. Different thermoluminescence characteristics were exhibited depending on the type or amounts of doping elements, and the highest luminance of 370 cd/m2 was obtained when Dy 10 % and Na 5 % were co-doped.

T. S. Eliot, in one of his later poetic dramas, The Conjìdential Clerk, shows the search for the mistaken identity dealing with lhe discovery of hero' s self for the eternal life in 버e common lives. From the titlc onwards the play also suggests a detective thriller interest concerned with Lhe investigation of a mystery or, at least, some business of a secret, confidential nature. In this respect, lhe elemenls of mystery and lheir function deserve to be analyzed. It appears via the elements of investigal.ion. coincidence. mystjfication, confession etc., which make the play fairly diverting and at the same time suggest symbolically its deeper meaning and lheme. AClually the process of invesligalion receives more extended treatment in this play than in I.he earlier ones. and the suspense is so well maintained that the play definitely achieves a technical smoothness 1101 to be seen in earlier plays. Therefore, this study aims to analyze the myslery lhriller elements of tbe play, The COlljìdential Clerk and investigate how they are used with special reference to its subject matter, the mistaken identity revealed in the process of self-identification through the discovery of self. As seen in the analysis, Eliot makes all the characters take part in the search for the mistaken identity of Colby Simpkins and in particular, lets a detective named Eggerson help M rs Guzzard as witness give evidence. 10 addition, he designs the story so that Eggerson can bring the whole affair to light by getting lhe c1ue to lhe identity problem which plays part in investigation. It matters that the discovery of hero’s true self is made Ihanks 10 the cooperalive efforts of all Ihe characlers in Ihis process, and here Ihe elemenls required 10 invesligation are of great help to structuring the basic frame of Ihe play.