การหาปริมาณเรเดียม-226 ในน้ำโดยใช้แมงกานีสไดออกไซด์ ที่เคลือบบนเส้นใยอะครีลิกเป็นตัวดูดซับ / ภาวิณี วิสัยแสวง = Determination of radium-226 content in water using manganese dioxide-coated acrylic fiber as an adsorbent / Pawinee Wisaisawang
This research was aimed to develop a technique for determination of radium-226 content in water using manganese dioxide-coated acrylic fiber as adsorber. The suitable conditions for coating acrylic fiber with KMnO[subscript 4] including color, temperature, KMnO[subscript 4] concentration and coating time were studied. In addition, the various parameters that might effect the adsorption of [superscript 226]Ra on Mn-coated fiber during collecting water sample were also investigated. Gamma spectrum of 609.3 keV of [superscript 214]Bi was used to analyze the [superscript 226]Ra concentration. The study of KMnO[subscript 4] coated on acrylic fiber found that the best used conditions are as follows: 0.5 M/L, 70-80 degree celcius, 20-30 min coating time and the color of Mn-coated fiber should be black.The amount 60 gram of Mn-coated fiber was capable for absorbing [superscript 226]Ra in 20-100 L of natural water sample.The appropriate range of pH and flow rate of collected water should be 6-7 and 1-2 L/min respectively. The efficiency of [superscript 226]Ra adsorpted on different sizes of Mn-coated local fibers gave the same results. This technique has minimum detectable activity, (MDA) 0.001 Bq/L.