Sensitization of thermoluminescent dosimeter CaSO4:Dy by co-doping with Mn in particular proportion for measurement of low radiation doses and the method of preparation of CaSO4:Dy, Mn
This invention relates to a thermoluminescent phosphor for the measurement of low radiation doses, including calcium sulphate (CaSO 4 ), Dysprosium (Dy) and manganese (Mn), wherein Dy and Mn are present as dopants. A process for the preparation of a thermoluminescent phosphor is also provided. The process includes the steps of: separately dissolving calcium sulphate (CaSO4), Dysprosium chloride (DyCh) and Manganese chloride (MnC) in hot concentrated sulphuric acid, to obtain sulphuric acid solutions of CaSO4, DyCb and MnCb; mixing the solutions; and followed by slow evaporation of the solvent to obtain a powder of microcrystalline phosphor of CaSO4:Dy, Mn.
1. A process for preparation of a thermoluminescent phosphor, comprising:
dissolving calcium sulphate (CaSO 4 ), Dysprosium chloride (DyCl 3 ) and Manganese chloride (MnCl 2 ) separately in hot concentrated sulphuric acid to obtain sulphuric acid solutions of CaSO 4 , DyCl 3 , and MnCl 2 ,
mixing the sulphuric acid solutions of CaSO 4 , DyCl 3 , and MnCl 2 , and
slowly evaporating a solvent of a mixture of the sulphuric acid solutions to obtain a powder of a microcrystalline phosphor comprising CaSO 4 :Dy, Mn.
2. The process as claimed in claim 1 , wherein slowly evaporating the solvent comprises heating the mixture of the sulphuric acid solutions of CaSO 4 , DyCl 3 , and MnCl 2 at 350° C. in a closed system.
3. The process as claimed in claim 1 , wherein the CaSO 4 :Dy, Mn comprises CaSO 4 :Dy(x), Mn(1−x), where x is from 0 to 1 mol %.
4. The process as claimed in claim 1 , wherein the CaSO 4 :Dy, Mn has a concentration of Dy of from 0 to 1 mol %, and wherein the Dy is dissolved in the sulphuric acid in steps of 0.025 mol %.
5. The process as claimed in claim 1 , wherein the CaSO 4 :Dy, Mn has a concentration of Mn of from 0 to 1 mol %, and wherein the Mn is dissolved in the sulphuric acid in steps of 0.025 mol %.
6. The process as claimed in claim 1 , wherein the CaSO 4 :Dy, Mn has a concentration of Dy of 0.025 mol % and a concentration of Mn of 0.075 mol %.
7. The process as claimed in claim 1 , wherein the microcrystalline phosphor is capable of being used in measuring low radiation doses involved in one or more of radiological medical imaging, nuclear medicine, and interventional fluoroscopy x-rays, for medical uses.
8. The process as claimed in claim 1 , wherein the microcrystalline phosphor is capable of being used in medical imaging.
9. The process as claimed in claim 8 , wherein the medical imaging comprises one or more of Radiography, Computed Tomography (CT), Fluoroscopy during angioplasty and angiography, and Mammography.
10. The process as claimed in claim 7 , wherein the medical use is one or more of urology, orthopaedics, cardiology, anaesthesiology, and/or dental and medical radiation research use.
11. The process as claimed in claim 1 , wherein a thermoluminescent intensity of the microcrystalline phosphor is at least 3.62×10 7 counts (a.u.) compared to standard CaSO 4 :Dy having a thermoluminescent intensity of 2.06×10 7 counts (a.u.).
12. The process as claimed in claim 1 , wherein a thermoluminescent intensity of the microcrystalline phosphor is at least 4.61×10 7 counts (a.u.) compared to standard CaSO 4 :Dy having a thermoluminescent intensity of 2.06×10 7 counts (a.u.).
13. The process as claimed in claim 1 , wherein a thermoluminescent intensity of the microcrystalline phosphor is from 3.62×10 7 to 4.61×10 7 counts (a.u.) compared to standard CaSO 4 :Dy having a thermoluminescent intensity of 2.06×10 7 counts (a.u.).