http://nopr.niscair.res.in/handle/123456789/4507 Special Issue on Luminescence and its Applications Search the Channel search http://nopr.niscair.res.in/simple-search http://nopr.niscair.res.in/handle/123456789/4526 Title: Luminescence studies in KMgF₃:Eu,Ag <br/> <br/>Authors: Madhusoodanan, U; Jose, M T; Indira, R; Rao, T K Gundu <br/> <br/>Abstract: A new sensitive material KMgF₃:Eu,Aghas been developed with double dopants europium (Eu) and silver (Ag) by melting equal molecular proportions of KF and MgF₂along with dopants (0.2 mol % each) in argon atmosphere. Luminescence studies have been carried out in this material to check its possible use in radiation dosimetry applications. Thermoluminescence (TL) studies in this material show that its TL sensitivity is three times that of the existing tissue equivalent material LiF:Mg,Ti (TLD-100), while KMgF₃ doped with Eu alone and Ag alone shows sensitivities equal to that of TLD-100. KMgF₃:Eu,Ag shows a major TL peak around 240^oCunlike TLD-100 which has a complicated glow curve shape. The TL emission spectra of gamma irradiated material show characteristic emission of Eu²⁺. Compared to KMgF₃:Eu, the emission intensity of Eu has been found more in KMgF₃:Eu,Ag. Photoluminescence studies show that there is no conversion of Eu²⁺to Eu³⁺ on gamma irradiation. Electron spin resonance (ESR) studies have been carried out in this material to check if there is any valance conversion of Eu and Ag. Both the irradiated as well as unirradiated materials show signal for Eu²⁺ ion and did not show any signal for Ag²⁺ion. Hence, in the presence of Ag⁺ more Eu²⁺is entering into the crystal lattice which enhances the luminescence efficiency. <br/> <br/>Page(s): 459-460 http://nopr.niscair.res.in/handle/123456789/4525 Title: Thermoluminescence characteristics of MgB₄O₇, MgB₄O₇:Mn and MgB₄O₇:Cu phosphors <br/> <br/>Authors: Rao, M Ramalingeswara; Rao, B Subba; Rao, N Poornachandra; Somaiah, K; Murthy, K V R <br/> <br/>Abstract: The thermoluminescence (TL) characteristics of gamma irradiated MgB₄O₇, MgB₄O₇:Mn and MgB₄O₇:Cu phosphors have been studied in the present paper. These phosphors are tried as candidates for PDP panel phosphors. The method of preparation is a standard solid state reaction method. Thermoluminescence studies of gamma irradiated MgB₄O₇ show a TL peak at 225°C with TL intensity around 65 units. The introduction of 1% dopants like Mn and Cu changes the TL pattern i.e TL peak temperature shifts towards higher side at 233°C. The introduction of Cu creates a hump around 290°C. <br/> <br/>Page(s): 456-458 http://nopr.niscair.res.in/handle/123456789/4524 Title: Thermoluminescence studies of BaMgAl₁₀O₁₇doped with Eu phosphors <br/> <br/>Authors: Zambare, A P; Prasad, A S Sai; Natrajan, V; Rao, B Nageswara; Murthy, K V R <br/> <br/>Abstract: BaMgAl₁₀O₁₇:Eu, phosphors have been synthesized in air atmosphere by high temperature solid state reaction. Two well defined thermoluminescence (TL) glow peaks are shown at 180 and 330°C under gamma irradiation. The TL emission spectra of samples reveal two emission peaks at 617 and 895 nm. These changes are probably due to electronic charges and sizes of Eu³⁺dopant ions. <br/> <br/>Page(s): 453-455 http://nopr.niscair.res.in/handle/123456789/4523 Title: <smarttagtype namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="country-region" downloadurl="http://www.5iantlavalamp.com/"><smarttagtype namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="place" downloadurl="http://www.5iantlavalamp.com/"><smarttagtype namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="City" downloadurl="http://www.5iamas-microsoft-com:office:smarttags"> Optically stimulated luminescence dating of artifacts excavated from Kangla, Manipur, India </smarttagtype></smarttagtype></smarttagtype> <br/> <br/>Authors: Singh, S Nabadwip <br/> <br/>Abstract: <smarttagtype namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="metricconverter"><smarttagtype namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="country-region" downloadurl="http://www.5iantlavalamp.com/"><smarttagtype namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="place" downloadurl="http://www.5iantlavalamp.com/"> Kangla, located at the heart of Imphal city, is almost intersected by 24°N latitude, 94°E longitude, 2619 feet above the mean sea level. An excavation in 2006 at the site by the State Archaeology Department has yielded potteries and bricks at different levels-1.09, 0.72 and 1.64 meter. Using coarse grain of quartz excavated from these artifacts, three samples have been dated using Single Aliquot Regenerative dose (SAR) protocol. A standard commercial Riso (Denmark) TL/OSL reader (model TL DA-15A) has been used for data acquisition. The optically stimulated luminescence (OSL) ages of the samples are in the range 1450-1500 A.D. </smarttagtype></smarttagtype></smarttagtype> <br/> <br/>Page(s): 450-452