Technology Division

Technology Division (TD) has been focusing on the activities which were stated in TAEA’s Establishment Law; Nr.2690. Studies carried in Technology Division are mainly based on, ionizing radiation and materials interactions ranging from polymers to metals. Thus investigation and some fundamental researches on detectors and dosimeters in terms of laboratory scale studies have been activated. Technology Division’s activities are also carried on personal and accident dosimeters, identification of irradiated food stuffs and dating of geological, archaeological and anthropological samples with Electron Paramagnetic Resonance (EPR), Optically Stimulated Luminescence (OSL) and Thermoluminescence (TL) techniques. Moreover TD’s laboratories give routine analysis service apart from SNRTC itself, to the other official and private sectors of Turkey, including universities, research centers and private companies.

Materials Unit

The Materials Unit is consisted of two main laboratories which are Materials and Characterization Laboratory and Microscopy Laboratory respectively. The studies carried in these laboratories are mainly based on the effects of ionizing radiation on materials. In conjunction with this, new materials which may widely be used in nuclear technology, industry, environment, medicine, agriculture, and food are studied in laboratory scale.

In Materials and Characterization Laboratory studies are mainly focused on the materials characterization methods using Electron Spin Resonance (ESR), thermal, crystallographic, some mechanical/chemical testing techniques, and etc. Therefore some of these available techniques are mentioned below.

A continuous microwave, X-Band, temperature controlled (100-5000K) ESR Spectrometer having an goniometer as an optional attachment, is used for the examination of paramagnetic samples ranging from irradiated/nonirradiated foodstuff, various conducting or nonconducting materials to archeological and/or geological ones which are searched for dating purposes also. For the characterization of thermal properties of materials, Differential Scanning Calorimeter (DSC) and Simultaneous Differential Thermogravimeter (SDT) are used.

In these techniques, change in mass, activation energy, transition temperature, melting point, reaction kinetics, specific heat, and etc of the samples under investigation can be detected. In addition to these, electrical resistivities of conducting, semiconducting and superconducting samples, are also measured with the help of a cryostat system in the range, from liquid nitrogen to room temperature. The crystallographic properties of samples in powder form, are studied by using an X-Ray Powder Diffractometer (XRD) running within a wide temperature range (between -180°C and +1600°C), both qualitatively and quantitatively.

In Microscopy Laboratory there are mainly two microscopes which are contact mode type Atomic Force Microscope (AFM) and Scanning Electron Microscope (SEM). As it is well known, no special sample preparation technique is required for a conducting or nonconducting sample to be investigated via AFM which gives three dimensional surface image even in atomic scale. In contrary, one should have a conducting sample (or a sample covered with a thin conducting layer) in order to get an image by a SEM. In this laboratory a novel, field emission gun type SEM system with X500.000 magnification capability, has already been installed recently. The above mentioned SEM is also equipped with an EDS system which is capable of identifying the elements from B to U in terms of both qualitative and quantitative meanings.

Dosimetry Unit

The main activities of the dosimetry unit are on personal and accident dosimeter, identification of irradiated food stuffs and dating of geological, archaeological and anthropological samples with Electron Paramagnetic Resonance (EPR), Optically Stimulated Luminescence (OSL) and Thermoluminescence (TL) techniques. Dosimetry unit has Co-60 and Cs-137 experimental gamma irradiation sources having the dose rates 0.79 kGy/h and 0.54 kGy/h (In July 2010), respectively. The dose rates of the gamma sources are traced by NPL (National Physical Laboratory) with fricke and alanine dosimeters certificated by NPL every year.

EPR DOSIMETRY  

  • Detection of irradiated foodstuffs
  • Dating of geological, archaeological and anthropological samples
  • Research on various organic and inorganic materials in means of accident dosimetry
  • Preparation of EPR/alanine dosimeters
  • Calibration of routine dosimeters (PMMA dosimeters)
  • The measurement of absorbed dose between 25Gy and 100 kGy in medical products and foodstuffs
  • Dose mapping

TL/OSL DOSIMETRY

  • The productions of synthetic minerals as personal dosimeter.
  • The investigations of materials as accident dosimeter.
  • Dating of geological and archaeological samples.
  • The detection of irradiated foodstuffs.

STANDARDS FOR HIGH-DOSE DOSIMETRY

  • ISO/ASTM 51607-04 -Standard Practice For Use of The Alanine /EPR Dosimetry System
  • ISO/ASTM 51261:2002-Guide For Selection And Calibration of Dosimetry Systems For Radiation Processing,
  • ISO/ASTM 51707:2005-Guide For Estimating Uncertainties In Dosimetry For Radiation Processing,
  • E1026-04E1-Standard Practice for Using the Fricke Reference-Standard Dosimetry System.

STANDARDS FOR IRRADIATED FOODSTUFFS

  • EN 1787:2005 –Detection of Irradiated Food Containing Cellulose by EPR Spectroscopy (The EPR dosimetry laboratory was accredited on EN 1787:2005 method by TURKAK).
  • EN 13708:2001-Foodstuffs-Detection of Irradiated Food Containing Crystalline Sugar By EPR Spectroscopy.
  • EN 1786:1998 –Detection of Irradiated Food Containing Bone –Method by EPR Spectroscopy.
  • EN 1788:2007 – Detection of Irradiated Food from Which Silicate Minerals Can Be Isolated- Method by Thermoluminescence.