The basic quantum theory is presented for the temperature dependence of the elastic constants of solids. The phonon-lattice interaction is invoked to explain the anomalous temperature dependence of CI2 in NaC1-like structure alkali halides. The calculated values of dCl,/dT for lithium and sodium halides are negative and dC12/dT for potassium and rubidium halides (except KF) are positive (showing an anomalous temperature dependence of C12). These results are in excellent agreement with available experimental data.On presente un calcul quantique fondamental sur la variation des constantes Blastiques des solides en fonction de la temperature. On attribue la dependence anomale des parametres C12 pour les haloides alcalins du type NaCl it I'interaction phonon-reseau. Les valeurs de dCl,/dT ainsi obtenues sont negatives pour le lithium et le sodium, mais positives (et par consequent anomales) pour les haloi'des ( s a d KF) du potassium et du rubidium. Les resultats obtenus sont en tres bon accord avec les valeurs experimentales que I'on a pu trouver.
The Kataoka-Yamada model for highly concentrated solid solutions has been used to calculate the microhardness of NaCl-NaBr, KCl-KBr, and KBr-KI systems. The extra hardness in mixed crystals is computed from the amount of hindrance in the transport of ion pairs in the fluctuating stress field produced by the random distribution of anions of different sizes. The theoretical results are in very good agreement with available experimental data.
In recent past fly ash is only being treated as waste and a source of air and water pollution but is in fact an eco - friendly and economically beneficial resource material for various applications and has also proven its worth over a period of time. The utilization of fly ash in several novel researches will also paves the path for systematic disposal of this waste material. The present paper involves the study of Thermoluminescence (TL) of different compositions of fly ash collected from National Thermal Power Corporation, Korba, Chhattisgarh, INDIA with (CaSO4:Dy) Phosphor. Thermo luminescence Dosimeters are regarded as the badge which absorbs the radiation when persons having TLD badges are exposed to radiation. We have to investigate and compare the glow curve behavior of pure phosphor and 10 %, 20 % and 30 % fly ash doped phosphor when it is exposed to gamma irradiation Cs137.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.