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[en] The abundance of major trace elements in water in the surface well, tube well, lake and river were measured. The technique outlined here is very useful in the study of the pollution of environmental radioactivity. For the above measurements the Si(Li) X-ray detection system was used in conjunction with a personal computer
[en] Ferroelectric lead zirconate titanate powder was composed of mainly the oxides of titanium, zirconium and lead. PZT powder was firstly prepared by thermal synthesis at different Zr/Ti ratios with various sintering temperatures. PZT thin film was fabricated on SiO2/Si substrate by using thermal evaporation method. Physical and elemental analysis were carried out by using SEM, EDX and XRD The ferroelectric properties and the switching behaviour of the PZT thin films were investigated. The ferroelectric properties and switching properties of the PZT thin film (near morphotropic phase boundary sintered at 800 C) could function as a nonvolatile memory.
[en] Cobalt (Co) 0.4 mol doped zinc oxide (ZnO) fine powder was prepared by solid state mixed oxide route. Phase formation and crystal structure of Co-doped ZnO (CZO) powder were examined by X-ray diffraction (XRD). Scanning Electron Microscopy (SEM) was used to observe the micro structure of Co doped ZnO powder. Energy Dispersive X-ray Fluorescent (EDXRF) technique gave the elemental content of cobalt and zinc. Co-doped ZnO film was formed on glass substrate by spin coating technique. Photovoltaic properties of CZO/glass cell were measured.
[en] Zeolite A was synthesized from hydrogel solution which prepared from silica and alumina precursors under hydrothermal condition at atmospheric pressure. Before preparing of hydrogel solution, the amount of raw materials which used in resulting hydrogel with appropriate mole ratio was calculated by material balance. In this study,totally ten experiments were carried out for zeolite A formation. The important parameters for these experiments were the kinds of precursors,their concentration (starting material composition), synthesis time and temperature. All product samples from these experiments were characterized by X-ray Diffraction (XRD), Scanning Electron Microscope (SEM) and analyzed by gravimetric method. The results show that the favourable sample for this research work which can be prepared with a molar composition of SiO2: Al2O3: 2Na2O: 70H2O by agitation at room temperature for 30 minutes, ageing at room temperature and crystallization at 95Ccentre dot centre dot for 24hrs. The percent yield of favourable result is 70%.
[en] In this research, two types of raw material source, rice husk and rice husk ash, were used. Among the rice husk samples, taungpyan sample was chosen because it contains the maximum silica content and treated with (1,3,5) wt% sulphuric acid (96% concentration) and citric acid (99% concentration). These acid treated taungpyan samples and nonacid treated taungpyan sample were burned at 900C for 30 min. For rice husk ash samples, ash samples from fluidized combustor, fluidized gasifier and brick factory were collected. All of the rice husk ash samples were purified by alkaline extraction method with (2-3) N NaOH solution and followed by acid precipitation method with 5 N H2SO4 solution. According to the analysis and characterization, acid treated taungpyan sample (5 wt% citric acid) with the highest silica content (99.906 wt% and crystallization form) was obtained.
[en] Over 250 cases of carcinoma of Breast in different stages, treated by Joint Cancer Clinic (JCC) of No (2) Military Hospital over 5 years (1987 to 1991) were analysed. Different combination of drugs CMF, CMF(P),CMFVP and COFA regimes were given either alone on in combination with local radiation therapy after surgery- lumpectomy or extended simple mastectomy. Hormonal therapy was also added to the standard method of treatment in most of the cases. Results were evaluated in different arms of treatment. The value of immunotherapy and neochemotherapy were also studied
[en] Moel calculations can be used to provide nuclear data for applications in science and technology. The energy averaged neutron induced nuclear reaction cross-sections particular for Al-27, Mg-24, Cr-52, Mn-55, Zn-64 and U-238 with neutrons of energy (0.005 to 10 MeV) are calculated using IAEA nuclear codes ''ABAREX'' and ''SCAT2''. The results are compared with those given in ENDF- 3 nuclear data
[en] Radioactive fallout in rainwater and air collected from Yangon Division (Ahlone, Yangon), Pago Division (Pago and Thanut Pin), Mandalay Division (Pyinoolwin, Mandalay and Meikhtilar), Mon State (Mawlamyine, Kyaikame, Beelin, Taungzun, Kyaikhto, Kinpunsakan and Thayetkone village), and Shan State (Larsoh) were measured by using low level Beta Counting System. It was found that the radioactivities were less than the maximum permissible level recommended by the International Commission on Radiological Production. (author)
[en] Sr doped BaTiO3 ceramics/crystals were prepared by conventional solid solution method and heat treated 925C for 2 hrs. X-ray diffraction analyses of the samples were carried out. Determine the variation of lattice parameter (a and c) and lattice distortion with dopant concentration Sr to BaTiO3 crystals
[en] Three biological expeditions was made from June 2003 to June 2004. Altitude is a major factor among the differences of flora and fauna distribution. Hkakaborazi (19296') is a reservoir of glaciers with permanent ice and snow from which rivers. Melikha and Maekha emanate. Ayeyarwaddy river formed from those two rivers and flow beside Myirkyina. Therefore, water quality of each river and their tributaries are cool and fresh. This quality can preserve endemic species. Unknown species of jellyfishes of Ayeyarwaddy river was collected from Myitkyina environ. Also, three different terrestrial habitats namely icy-mountain range, cool temperature and subtropical forest can conserve their characteristic flora and fauna. Flora and fauna distribution is always related to their habitat or environs. Diagnostic features of each species were recorded by photographs. The findings were discussed from conservation point of view.