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13 NEUTRON ACTIVATION ANALYSIS (NAA)

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Presentation on theme: "13 NEUTRON ACTIVATION ANALYSIS (NAA)"— Presentation transcript:

1 13 NEUTRON ACTIVATION ANALYSIS (NAA)

2 SPECTROSCOPY UVi-Vis (Ultra Ungu-Tampak) AAS (Absorpsi) AES (Auger Electron) RAMAN MOESBAUER NMR (Nuclear Magnetic Resonance) FTNMR ESR (Electron Spin Resonance) PHOTOACUSTIC MS (Mass) EIS (Electron Impact) ISS (Ion Scattering) XPS (Xray Photoelectron) UPS (Ultraviolet Photoelectron) SPECTROPHOTOMETRY UV-Vis IR FLUORESCENCE PHOSPHORESCENCE RADIOCHEMICAL/ NUCLEAR METHOD : Radioactive Tracer Spectrometry Spectrometry/LSC (Liquid Scintillation Counter) NAA (Neutron Activation Analysis) Mosbauer THERMOMETRIC METHOD -DTA -DTG OTHER METHODS SPECTROMETRY FLAME EMISSION ATOMIC ABSORPTION XRF NUCLEAR METHOD ( , ,  ) MS (MS/MS,ICP-MS,GC-MS, LC-MS,LC-MS-MS, IMS) CHROMATOGRAPHY GC LC HPLC Tandem: GC-MS, LC-MS, LC-MS-MS ELECTROMETRIC METHOD pH/ISE Potentiometric Titration Voltammetry Polarography (PDV,DME,DPP) Electrogravimetry and Coulometry Conductometry CHEMICAL ANALYSIS OF SURFACES ISS (Ion Scattering Spectrometry) SIMS (Secondary Ion Mass Spectr.) AES (Auger Emission Mass Spectr.) ESCA (Electron Spectroscopy for Chemical Analysis) PENGGOLONGAN METODE ANALISIS INSTRUMENTAL KIMIA 13

3 TEKNIK ANALITIK NUKLIR PENGUKURAN LANGSUNG RADIOAKTIVITAS ( ,  dan  ) PENGUKURAN TIDAK LANGSUNG  METODE AKTIVASI -LANGSUNG (prompt): PGNAA, PIXE NAA -KASEP (delayed): NAA, CPAA, PAA -IBA: NRA, PIGE, RBS, PIXE  PENAMBAHAN PERUNUT RADIOAKTIF  P ENGGUNAAN SUMBER RADIASI -ABSORPSI: Radiasi: ,  dan neutron -ANALISIS HAMBURAN (scattering) -PENDAR : PENDAR SINAR (XRF) Gambar 1: Skema teknik analisis nuklir (TAN) 13 DATA RADIOAKTIVITAS DATA KADAR UNSUR/LOGAM

4 -Jenis sampel padat, cair, gas -Tidak memerlukan perlakuan kimia -Tidak terkontaminasi -Analisis unsur serentak (Multiunsur) -Memiliki sensifitas & selektivitas tinggi -Mampu menganalisis unsur orde μg, ng -Dll Keunggulan Analisis Aktivasi Neutron 13

5 ANALISIS AKTIVASI NEUTRON (AAN) 13 KONSEP NAA PGNAA

6 NEUTRON ACTIVATION ANALYSIS A+1 X A+1 Y Z+1 NEUTRON INTERACTION OFTEN PRODUCES RADIOISOTOPES : ENTIRE PERIODIC TABLE CHARACTERISTIC RADIATIONS, e.g., GAMMA RAYS ARE MEASURED : CONCN. OF ISOTOPES (ELEMENTS) NAA PGAA For neutron induced reactions V C =0 It enters all nuclei and binds to it. CN is in excited state. 13

7 Figure 2: A typical reactor neutron energy spectrum showing the various components used to describe the neutron energy regions. Although there are several types of neutron sources (reactors, accelerators, and radioisotopic neutron emitters) one can use for NAA, nuclear reactors with their high fluxes of neutrons from uranium fission offer the highest available sensitivities for most elements. Different types of reactors and different positions within a reactor can vary considerably with regard to their neutron energy distributions and fluxes due to the materials used to moderate (or reduce the energies of) the primary fission neutrons. However, as shown in Figure 2, most neutron energy distributions are quite broad and consist of three principal components (thermal, epithermal, and fast). Neutrons 13

8 Slide#8 The Kartini Facilities TRIGA Mark II Reactor (100 kW) Neutron Radiography (in experient) Thermal Neutron Activation Analysis Fast Neutron Activation Analysis (14 MeV in experient) Prompt Gamma Activation Analysis (in experient) Spectroscopy ( , , and  ) Radiation Handling Areas Computational Capabilities : AccuSpec, Shampo, Maestro and Genie software Gamma Detector: NaI(Tl), HPGe, Ge(Li) 13

9 Sistem iradiasi dg rabit system/pneumatic REAKTOR KARTINI TRIGA MARK II, 100 kW Spektrometer  13 Activation method delayed (AAN)

10 13 TERAS REAKTOR KARTINI TIDAK BEROPERASI

11 13 TERAS REAKTOR KARTINI SAAT BEROPERASI

12 FNAA S 13 Maret015 Limit Deteksi dalam ppb (10 -9 )

13 ELEMENTDETECTION LIMIT [g] In, Eu, Dy to Mn, Lu to Co, Br, I, Sm, Ho, Hf, Re, Ir, Au, Th, U to Na, Cl, Cu, Ga, Ge, Se, As, Pd Sb, Te, Yb, Ta, W, Pt to K, Sc, Ni, Rb, Sr, Y, Nb, Ru, Cd Sn, Gd, Tb, Tm, Os, Hg to * CALCULATED USING A NEUTRON FLUX OF n/SEC/Cm 2 & A 20% RELATIVE EFFICIENCY DETECTOR DETECTION LIMITS DEPENDS ON FLUX, DETECTION EFFICIENCY AND IRRADIATION TIME 13

14 Perbandingan Limit Deteksi berbagai Metode METODE LIMIT DETESI AAS – g AES – g FLAME EMISSION – g ANODIC STRIPP. VOLTAMETRY – g MASS SPECTROMETRY g ICP-MS g GAS CHROMATOGRAPHY – g XRF – g NAA – g IBA – g 13

15 14 MeV-NAA : FNAA (Fast Neutron) 13

16 13 14 MeV-NAA : FNAA  NEUTRON GENERATOR : Cockroft-Walton accelerator principle  NEUTRONS OF ~14 MeV FROM t(d,n)  RXN  AVAILABLE FLUX: 10 9 n.cm -2.s -1 from a neutron yield of 2.5x10 11 n.s -1  Threshold reactions:(n,p), (n,2n), (n,  ) etc.  Inelastic scattering rxns (n,n’  ): C, O and N (200, 100 and ~20 mb respectively)  Determination of many elements including C, N and O possible  Important tool for detection of explosives (TNT, RDX etc.): high C, N, O high N/O and/or C/O ratio

17 13 Element Nuclear ReactionProduct Half-lifeGamma-ray (keV) O 16 O (n, p) 16 N7.13 s6130, 7120 N 14 N (n, 2n) 13 N9.97 min511 F 29 F (n, p) 19 O30 s197.4 Mg 24 Mg (n, p) 24 Na15 h Si 28 Si (n, p) 28 Al2.24 min1779 P 31 P (n,  ) 28 Al 2.24 min1779 Fe 56 Fe (n, p) 56 Mn 2.58 h847 Cu 63 Cu (n, 2n) 62 Cu10 min511 Zn 64 Zn (n, p) 64 Cu12.8 h511 Zr 90 Zr (n, 2n) 89m Zr4.18 min588 ThFission-Delayed neutron UFission-Delayed neutron 14 MeV-NAA : FNAA

18 PROMPT GAMMA-RAY NAA: PGNAA 13

19 PGAA WORK INVOLVED  SETTING UP OF A SYSTEM: DETECTION & SHIELDING  CHARACTERISATION OF THE NEUTRON BEAM  EFFICIENCY DETERMINATION (~ MeV)  DETERMINATION OF PROMPT k 0 -FACTORS  ANALYTICAL APPLICATION  PGNAA is an online technique : Measurement of capture gamma rays after neutron absorption 1.It is complementary to conventional NAA 2.Analysis of low Z elements (H, B, C, N, Si, P,S): Best for H and B analysis 3.Determination of many elements including Hg, Cd, Sm & Gd  The k 0 -based PGNAA: Advantageous 13

20 Some important features of PGNAA Ability to determine light elements (H,B,N,C,P,S,Si) Analysis of biological sample Ability to determine toxic elements (Cd, Hg) with high sensitivity Environmental samples Nondestructive multielemental bulk analysis Flexibility of sample size and shape Archeological, geo- and cosmo- chemical samples Isotopic analysis is possible (S,Si,Ni) 13

21 Neutron beam line Lead shield Boron Carbide HPGe detector Beam Dump Sample Holder Schematic representation of the PGNAA set up BGO shield 13

22 WORK SETTING UP PGNAA SYSTEM CALIBRATION & CHARACTERISATION k 0 FACTORS BACKGROUND PROBLEMS CAPTURE GAMMA RAYS IN 60 Co APPLICATIONS A) ANALYSIS OF SAMPLES CONTAINING B,Cd,Gd,Hg B) ANALYSIS OF A FEW CRMS C) ANALYSIS OF METEORITES D) ANALYSIS OF SS ALLOYS JRNC 250 (2001) 303, NIMA 457 (2001) 180 NIM A 516(2004)143, ANAL CHIM ACTA ( COMM), ANAL CHEM ( PREP) 13

23 Substance HCNOClC/OC/NCl/O PlasticsM-HHH-LMM-NMVH- NarcoticsHHLLMH, >3HVH Explosives L-MMHVHM-NL, <1 L-M L – Low, M – Medium, H – High, VH- Very high Elemental densities and ratios of three classes of substances 13

24 METODEAANMETODEAAN 13 Maret

25 NAA-Kay zero (in experient) 13

26 NAA k 0 -BASED NAA SINGLE COMPARATOR: Au DETMN: f,  & k 0 VALIDATION: CRMs k 0 -BASED INTERNAL MONO STANDARD NAA IN-SITU REL-EFFICIENCY LSNAA STANDARD-LESS NAA k 0 -BASED PGNAA EFFICIENCY k 0 -FACTORS APPLICATIONS APPLICATIONS Reference materials, Ruby, Emerald, Sediment, Leaf, Cereal, Mn-Nodules Serpentines, Zircaloy, SS, Aluminium, Meteorites Chemical NAA, Radiochemical NAA Radiochemical NAA Speciation NAA R & D WORK ON NAA Collaborations Development of Methodologies: 13

27 RADIOACTIVITY MEASUREMENT RADIOACTIVITY IN ENVIRONMENT 1. ESSENTIALLY NATURAL PROCESSES, e.g., RADON & DP 2. ANTHROPOGENIC : MINING, PROCESSING, REPROCESSING DIAGNOSTIC, TESTING, ACCIDENTS AS ON NOW FIRST IS MUCH MORE RADIOACTIVITY MEASUREMENTS : , ,  LARGE SAMPLES OF SOIL, WATER; AIR PARTICULATES COLLECTED ON FILTERS; FOOD STUFFS CHEMICAL PRECONCENTRATION 13

28 * Toxicity depends on species * The five major species: As(III), As(V), MMA, DMA and AsB * In natural water two major species: As(III) & As(V) * Drinking water limit (As): 10 ng.mL -1 (WHO) SPECIES OF ARSENIC ARSENIC SPECIES: WATER SYSTEM Standardized two chemical separation methods: (i)Ion exchange separation (ii) Solvent extraction 13

29 INORGANIC ARSENIC SPECIATION : Dowex 1X8 in acetate form As(V) As(III)+As(V) IN 8M AcOH 0.12M HCl As(III) TOTAL ARSENIC IN DRINKING WATER BY INAA: ng.mL -1 in samples from Kolkata city PERCENT RECOVERIES OF ARSENIC SPECIES QUANTITATIVE (96-100%) IN BOTH ION EXCHANGE AND SOLVENT EXTRACTION METHODS SOLV.EXT.: APDC- MIBK IN pH

30 TERIMA KASIH 13


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