940 likes | 1.23k Views
Varian Technologies korea., Ltd. Introduction to Atomic Absorption Spectrometer. 조 창 래. Varian Australia, Melbourne. AA280 Configurations Available. AA280 Zeeman or D2 (graphite furnace). AA280 FS (Flame). Measurement Range. ICP-MS. 200 150 100 80 40. ICP-OES.
E N D
AA280 Configurations Available AA280 Zeeman or D2 (graphite furnace) AA280 FS (Flame)
Measurement Range ICP-MS 200 150 100 80 40 ICP-OES Price $k GF-AAS Flame AA 100% 0.1 % ppm ppb ppt ppq
Sir Isaac Newton 이 1600년말 스펙트럼 발견 광학 스펙트럼의 기본형 태양광선 프리즘
1802 Wollaston 이 태양광선에서 검은 spectrum발견 Fraunhofer 정밀분석 회색선의 요인은 대기중에서 태양의 특정 파장이 흡수됨 Fraunhofer
Kirchhoff & Bunsen 공동실험 (1) 광원 렌즈 렌즈 금속끝에 염첨가 백색종이 버너 흡수선 프리즘
흡수 vs 방출 Fraunhofer 흡수선 Ba Na K Cu 방출선 900 nm 190nm • 원소의 정성분석
H He Li Be B C N O F Ne Na Mg Al Si P S Cl Ar K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe Cs Ba La Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn Fr Ra Ac Flame Only Flame & Furnace Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr 주기율표
Radio waves Gamma rays Microwaves X rays Infrared UV 1nm 100nm 1mm 1m Visible Region nm 430 500 560 650 750 600
바닥상태 원자 Orbitals Neutrons Protons Electrons
원자의 에너지흡수 최 외각 전자 들뜬원자의 상태 h 에너지 흡수 바닥상태의 원자
Energy Level Diagram 전자에너지 이동 E4 E3 E2 E1 Eo • 1 • 2 • 3 • 4 • 5 • 6 공명선은 바닥상태 (Eo)로부터시작
공명선은 바닥상태로부터 유래 원자흡수과정 에너지 전이 E3 E2 태양광선 대기흡수 E1 Eo • 4 • 3 • 2 • 1 • 4 • 2 • 1 • 3
Energy Level Diagram for Pb E4 E3 E2 E1 Eo 261.4 202.2 217.0 283.3 Wavelength in Nanometers
Absorption Energy Diagram(Few Lines/Element) Excitation E 이온화 } E3 들뜬상태 E2 c Energy E1 b a b c d a Eo바닥상태
Emission Energy Diagram(Many Lines/Element) 방 출 E 이온화 } E3 들뜬상태 E2 c Energy E1 b a b c d a Eo바닥상태
원자흡수 과정 Io It Resonance Non-resonance Fill Gas Resonance
A = log () = abc Beer-Lambert 흡수치 계산법 Io It • c A Where: A= 흡광도 a = 흡수계수 Io = 입사광 세기 b = 길이 It = 투과광 세기 c = 농도
투 과흡 수 100 % 0 10 % 1 1 % 2 0.1 % 3 % 투과량 vs 흡광치
A • abc Beer-Lambert 법칙 이론 선 A = abc A b s 실제선 Conc
Unabsorbed radiation, stray light Hollow cathode lamp line width broadening Monochromator slit is too wide Disproportionate decomposition of molecular species Reasons for Non-linearity for Calibration Graphs
Flame atomization Graphite furnace atomization Vapor generation Atomizers
Air - C2H2 flame / 2125 ~ 2400(oC) : Cu, Pb, K, Na, etc. (Air) - N2O - flame / 2600 ~ 2800(oC) : Al, Si, W Both : As, Ca, Cr, Mg, Os, Se, Sr Fuel - C2H2 Oxidant - Air in Air/C2H2 N2O in N2O/C2H2 Fuel rich flame = Reductant flame Fuel thin flame = Oxidant flame Flame Types
1) Nebulization M+ + A- (Solution) 2) Desolvation M+ + A- (Aerosol) 3) Liquefation MA (Solid) 4) Vaporization MA (Liquid - Gas) 5) Atomization M0 + A0 (Gas) 6) Excitation M* (Gas) 7) Ionization M+ + e- (Gas) Flame Atomization
What is SIPS? • SIPS-20 dual pump system provides additional benefits: • On-line addition of chemical modifiers e.g. • Ionization suppressants • Internal standard correction • On-line Standard Additions calibration from one standard • On-line preparation of analytical spikes from 1 Std.
Schematic of SIPS-10 Operation • Sample is pumped to a Tee • Tee is also connected to diluent and outlet flows to nebulizer • Stop pump, only diluent is aspirated through nebulizer • Start pump, sample is pumped and mixed with diluent as it flows to the nebulizer • Pump speed controls dilution ratio applied - balance of nebulizer flow made-up of diluent • Typical dilution error < 2 %
Schematic of SIPS-20 Operation • SIPS-20 with 2 pumps allows sample to be introduced with another solution e.g. standard, modifier, internal standard • Proportion of solution added to sample is controlled by relative pup speed • Can “spike” sample with varying amounts of modifier – providing new capabilities e.g. on-line standards additions, internal standarization • Sample pump speed is reduced, compared with SIPS-10 operation, to prevent flooding of nebulizer
Steps in Running SRM Wizard Examine the results(30 to 40 mins. later) Shape maximum is the optimum setting Pressing OK creates a method with the optimum settings
Enhanced Tube Lifetimes – Precision Comparison Signal graphics for sample at 400th & 4,000th firing Based on 10 replicates per sample for a 30ug/L Cu Ave precision < 0.5% RSD
1) Drying 2) Ashing(Pyrolysis) 3) Cool down(optional) 4) Atomization 5) Clean out 6) Cool down Furnace Atomization
Water Cooling Gas Out Sealed Quartz Window Optical Path Gas Inlet Flexible Seal Workhead
비불꽃 원자화 과정 Clean Out Atomize T E M P Cool Down Ash Dry T I M E
1) Spectral interference 2) Chemical interference 3) Ionization interference 4) Matrix interference 5) Non-specific interference Interferences