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(Click for frequent words.) 80 atomic emission spectroscopy 75 mass spectrometry ICP MS 73 aqua regia digestion 71 ICP AES 71 ICP MS 71 atomic emission spectrometry 71 ME ICP# 71 Inductively Coupled Plasma 71 ICP AES analysis 70 Inductively Coupled Plasma ICP 70 emission spectrometry 70 element ICP 69 ICP ES 69 Atomic Emission Spectroscopy 69 acid digestion 68 ICP OES finish 68 ME MS# 67 multi element ICP 67 tri acid digestion 67 ICP MS analysis 66 optical emission spectroscopy 66 aqua regia digest 66 atomic absorption 66 multi acid digestion 66 aqua regia 66 ICPMS 65 ICPAES 65 Aqua Regia digestion 65 lithium metaborate fusion 65 ICP AES finish 65 Mass Spectrometry ICP MS 65 assay fusion 64 aqua regia acid digestion 64 Au ICP# 64 ICP OES 64 sodium peroxide fusion 64 atomic absorption spectroscopy 63 ICP ES finish 63 Atomic Absorption Spectroscopy AAS 63 plasma mass spectrometry 62 Au AA# 62 Sodium Peroxide Fusion 61 Aqua Regia 61 ICP mass spectrometry 61 #g aliquot 61 aqua regia leach 61 Inductively Coupled Plasma Emission 61 atomic absorption spectroscopy AAS 61 ICP inductively coupled 61 element ICP MS 61 Atomic Absorption finish 61 Fire Assay 61 total digestion ICP 61 absorption spectroscopy 60 atomic absorption spectrometry 60 Atomic Absorption 60 atomic absorption finish 60 atomic absorption AA 60 aqua regia digestion ICP 60 Atomic Absorption Spectrometry 60 ICP Inductively Coupled Plasma 60 element ICP analysis 59 mass spectroscopy 59 ICP AES technique 59 ICP AES Method 59 mass spectrometry MS 59 isotope dilution 59 ICP spectrometry 59 lithium borate fusion 59 Optical Emission Spectroscopy 59 acid digestion ICP 59 multielement 59 emission spectrometer 58 atomic absorption methods 58 X ray fluorescence 58 ICP MS AAS 58 Atomic Absorption AA 58 element inductively coupled 58 EDAX 58 XRF analysis 58 ME ICP 58 Energy Dispersive X ray 58 Spectrometry 58 assay atomic absorption 58 AAS finish 58 ALS Chemex labs 58 Mass Spectrometry MS 58 Inspectorate Labs 58 Atomic Emission Spectrometry 58 Neutron Activation 57 lanthanide 57 Pb Cu 57 X ray fluorescence XRF 57 Au Pt 57 X Ray Fluorescence 57 UV VIS 57 EDXRF 57 Accurassay 57 palladium Pd 57 Fourier transform infrared spectroscopy 57 ALS Chemex laboratories 57 DEV DA TOMAR NEXT 57 atomic absorption ore 57 PGM ICP# 57 platinum Pt 56 Gravimetric finish 56 ALS Chemex Laboratory 56 element ICP AES 56 Aqua Regia Digestion 56 graphite furnace 56 energy dispersive x 56 rhodium Rh 56 Atomic Absorption Spectrometry AAS 56 capillary electrophoresis 55 Actlabs 55 gravimetric 55 CdSe 55 Swastika Laboratories 55 electron diffraction 55 acid digestion ICP AES 55 tetraborate fusion 55 Activation Laboratories Ltd 55 SGS Minerals 55 scanning tunneling microscopy 55 optical spectroscopy 55 hydrochloric acids 55 neutron activation 55 ALS CHEMEX Laboratories 55 liquid chromatography tandem 55 ALS Chemex Lab 55 ICP analyzes 55 Pt Pd 55 ALS Laboratories 55 Genalysis Laboratory Services 54 Induction Coupled Plasma ICP 54 spectroscopic technique 54 gas chromatography 54 UV Visible 54 #g aliquots 54 portable XRF 54 triple quadrupole mass spectrometry 54 X ray diffraction 54 assisted laser desorption 54 tunable diode laser 54 flame AAS 54 argon plasma ICP 54 lithium beryllium 54 performance liquid chromatography 54 x ray fluorescence 54 Induced Coupled Plasma ICP 54 emission spectroscopy 54 Ion Trap 54 colorimetric 54 Yttrium 54 Mobile Metal Ions 54 monochromator 54 cited krypton strontium 54 spectroscopic analysis 54 SELDI TOF MS 54 metallic sieve 54 lithium metaborate tetraborate fusion 54 Acid Digestion 54 Au GRA# 54 assay atomic adsorption 53 SGS Laboratories 53 XRD 53 cadmium selenium 53 FA AAS 53 ray fluorescence 53 hydrofluoric nitric perchloric 53 MALDI MS 53 leach CIL 53 nanopowder 53 circular dichroism 53 spectroscopic techniques 53 thiosulfate 53 mass spectrometry GC 53 confocal laser scanning 53 gram aliquot 53 conductive epoxy 53 fluorescence spectroscopy 53 PCR RFLP 53 Assayers Canada 53 zirconium Zr 53 X ray Fluorescence XRF 53 petrography 53 spectrometry 53 electron microprobe 53 gram pulps 53 conventional atomic absorption 53 ionization mass spectrometry 53 samarium 52 Activation Laboratories 52 Genalysis Laboratories 52 LC-MS/MS 52 Spectrometers 52 dilute nitric acid 52 electrowinning 52 Ultratrace 52 photoelectron spectroscopy 52 Ytterbium 52 rubidium 52 x ray fluorescence XRF 52 ICP# 52 ZrO 2 52 gravimetry 52 SPECTRO 52 nanocrystalline 52 spectroscopy 52 Techni lab 52 X ray diffraction XRD 52 interferometric 52 Gas Chromatography Mass Spectrometry 52 ALS Chemex laboratory 52 Chemex Labs 52 triple quadrupole 52 Coarse reject 52 gas chromatograph 52 scanning electron microscopy SEM 52 gram aliquots 52 X ray absorption spectroscopy 52 electrodeposition 52 yttrium barium copper 52 element geochemistry 52 spectrophotometry 52 Thermo Scientific LTQ Orbitrap 52 Scanning Electron Microscope SEM 52 osmium 52 dimensional gel electrophoresis 51 ALS Chemex assay 51 peroxide fusion preparation 51 neutron activation analysis 51 ALS Chemex Laboratories 51 Acme Analytical Labs 51 neutron diffraction 51 QEMSCAN 51 scanning electron microscopy 51 Cavity Ring Down 51 microprobe 51 x ray absorption spectroscopy 51 Absorption Spectroscopy 51 liquid chromatography mass spectrometry 51 retested utilizing 51 Genalysis 51 Nd YAG 51 using sodium peroxide 51 synchrotron X ray 51 ACME laboratories 51 optically pumped 51 porphyrin 51 handheld XRF 51 acid soluble 51 microcapillary 51 magnetic resonance NMR spectroscopy 51 AMMTEC 51 comminution 51 Spectroscopy 51 TSL Laboratories 51 Geochemical analyzes 51 assay AAS 51 energy dispersive X 51 fusion XRF 51 Terbium 51 induced fluorescence 51 ZnS 51 Accurassay Laboratories 51 Activation Labs Actlabs 51 mass spectrometric 51 Activation Laboratories Ltd. 51 magnesium fluoride 51 transmission electron microscopy 51 Copper Cu 51 Pt Pd Au 51 ion mobility 51 gram subsample 51 microfabricated 51 triple quadrupole mass spectrometer 51 cadmium sulfide 51 Cu Pb 51 XRF analyzer 51 cadmium zinc telluride 50 atomic adsorption finish 50 magnetic resonance spectroscopy 50 hydrometallurgical processing 50 ALS Chemex analytical 50 gravimetric finish 50 angle resolved photoemission 50 Abilab 50 spectroscopic 50 Colorimetric 50 geochemical analyzes 50 fluorescence quenching 50 chemometric 50 MALDI-TOF/TOF 50 dispersive 50 photodiode array 50 iTRAQ 50 allotrope 50 NanoSIMS 50 atomic absorption techniques 50 method ME MS# 50 Conductivity Analyzer 50 spectrometer 50 Phoenix Microscopy Electrochemistry 50 ALS Chemex Labs 50 Cyanidation 50 fluorescence resonance energy 50 Raman microscopy 50 diffractive 50 ionisation 50 desorption electrospray ionization 50 ISO IEC #:# accredited 50 Mass Spectrometer 50 quantitative PCR 50 Flow cytometry 50 Cu Pb Zn Ag 50 electrospray ionization 50 assay 50 liquid chromatograph 50 laser ablation 50 electrospray ionisation 50 Acme Analytical 50 ICP AAS 50 ALS Minerals 50 differential scanning calorimetry 50 gram pulp 50 particle sizing 50 potassium feldspar 50 XRF 50 emission spectrometers 50 Enzyme Leach 50 Accurassay Labs 50 laser scanning confocal 50 froth flotation 50 ion microprobe 50 spectroscopic methods 50 yttrium 50 microcavities 50 electroless nickel immersion 50 stable isotope 50 transmission electron microscopes 50 mass spectrometry 50 uses nitric 50 chemiluminescence 50 assay ELISA 50 MALDI TOF 49 dielectric permittivity 49 laser diffraction 49 nanoflow 49 QTOF 49 paramagnetic 49 pseudomorphic 49 Indium Phosphide 49 X Ray Diffraction 49 ion chromatography 49 Fire Assay AAS 49 transcriptomics proteomics 49 microstructured 49 carbonyl sulfide 49 Orbitrap 49 boron nitride 49 Leachwell 49 Acme Analytical Laboratories 49 NITON 49 leachability 49 NIST traceable 49 Swastika Ontario 49 equivalent CuEQ 49 Microscopy Electrochemistry 49 photothermal 49 chromatin immunoprecipitation 49 Mineral Resource estimation 49 fused silica 49 rock geochemistry 49 acid leach 49 Scanning Electron Microscopy 49 vibrational spectroscopy 49 photon counting 49 nucleic acid extraction 49 Scanning Probe Microscopes 49 indium gallium arsenide InGaAs 49 LTQ 49 SGS Geosol 49 QRT PCR 49 SAXS 49 SGS Mineral Services 49 GTAW 49 element ICP OES 49 organometallic 49 LiNbO3 49 laser spectroscopy 49 MALDI TOF TOF 49 Raman spectrometer 49 ALS Laboratory 49 Dynamic Light Scattering 49 physico chemical 49 VeraCode 49 calorimetric 49 Zn Cu 49 CIMM Peru 49 VUV 49 nanocatalysts 49 carbene 49 ALS Chemex 49 cyanide leaching 49 MXA signal 49 Gas Chromatography 49 Au Eq 49 Tansy O'Connor Parsons 49 Polymet Labs 49 spectro 49 spectrometric 49 Nanoindentation 49 neutron scattering 49 Laboratoire Expert 49 X ray spectroscopy 49 SGS Minerals Services 49 powder diffraction 49 fluorescence detection 49 7AR 49 Nova NanoSEM 49 FT4 49 FT IR spectroscopy 49 Tarkwa Ghana 49 NMR spectra 49 mass spectrometer 49 Adsorption 49 Activation Labs 49 fire assay gravimetric 49 force microscopy AFM 49 covalently bound 49 nanoclusters 49 Raman Spectroscopy 49 electron optics 49 nuclide 49 FT NIR 49 Chemex Laboratories 49 Loring Laboratories 49 laser desorption 48 AGAT Laboratories 48 sulphide mineral 48 polaritons 48 spectrophotometers 48 Au AA# method 48 UV absorbance 48 flow cytometric 48 gravimetric methods 48 Microwave Imaging Radiometer 48 differentially expressed proteins 48 P 4E 48 ellipsometry 48 transfer FRET 48 caustic fusion diamond 48 computed tomography SPECT 48 interpolate grades 48 Taqman 48 X ray spectrometer 48 amorphous silica 48 mineralogical analysis 48 Raman spectra 48 Assay Labs 48 geochemical 48 SGS Lakefield 48 using #g aliquots 48 perovskite 48 automated nucleic acid 48 WS CRDS 48 chromatin immunoprecipitation ChIP 48 molecular spectroscopy 48 X ray diffractometer 48 ACME Laboratories Vancouver 48 scintillator 48 Geoanalitica 48 Finite element 48 plasmon 48 scanning electron microscopes 48 reanalyzed using 48 immunoblotting 48 multislice 48 #.#gpt [004] 48 blackbody 48 barium titanate 48 FT IR 48 bosonic 48 absorption spectra 48 ACME Labs 48 MALDI 48 photonic bandgap 48 American Assay Laboratories 48 scanning tunneling 48 acousto optic 48 oxide nanoparticles 48 spectrophotometric 48 2D gel electrophoresis 48 magnetometry 48 interferometry 48 +# micron 48 mass spectrometry LC MS 48 cell lysate 48 Rheological 48 pathfinder elements 48 x ray diffraction 48 Femtosecond 48 APiX 48 Sample pulps 48 bottle roll cyanidation 48 Assay Laboratory 48 HPLC MS 48 gas chromatographs 48 Fourier transform 48 re assayed 48 petrographic 48 flotation concentrate 48 polymerized 48 NIR spectroscopy 48 Swastika Laboratories Ltd. 48 microfocus X ray 48 Lakefield Ontario 48 gel electrophoresis 48 Conductivity Analyzer MECA 48 Microprobe 48 photomultiplier tube 48 Spectroscopic 48 assayed 48 pyrometallurgical 48 situ hybridization 48 Situ Hybridization FISH 48 process flowsheet 48 zinc sulfide 48 Alpha Particle 48 strict QA QC 47 caustic dissolution 47 flotation testwork 47 perchloric acid 47 neutral mass spectrometer 47 SGS Laboratory 47 maXis ™ 47 vapor deposition 47 MALDI TOF mass spectrometry 47 hydrometallurgy 47 Arsenic trioxide 47 photoelectron 47 #.#/lb Pb 47 laser capture microdissection 47 ALS CHEMEX 47 neodymium praseodymium 47 Thermo Scientific ARL 47 microfocus 47 enzyme immunoassay 47 FTIR 47 Yttrium Y 47 optical waveguides 47 element geochemical 47 reverse transcriptase polymerase chain 47 spectrophotometer 47 elemental composition 47 aluminum nitride 47 Annexin V 47 isotopic 47 x ray crystallography 47 acanthite 47 FTIR spectroscopy 47 exfoliated graphene 47 helium atom 47 lithium tantalum 47 Elements PGE 47 UV Vis 47 assay detects 47 drillhole database 47 SRC Geoanalytical Laboratories 47 elastic moduli 47 favorable lithologies 47 reassayed 47 SYBR Green 47 X ray microscopy 47 Au #g 47 Raman spectroscopy 47 Si substrate 47 Colossus COOMIGASP joint venture 47 magnetic bead 47 Gas Chromatograph Mass Spectrometer 47 ultracentrifugation 47 Western blotting 47 Dip Pen Nanolithography ® 47 enhanced laser desorption 47 oligonucleotide ligation 47 Senior Geochemist 47 Activation Laboratory 47 manganite 47 SGS Labs 47 grindability 47 photoluminescence 47 electron scattering 47 bDNA 47 brightfield 47 Transworld Laboratories 47 geochemical surveys 47 InSb 47 Confocal 47 geochemical assay 47 reagent blanks reference 47 nanoparticle coated 47 self assembled monolayers 47 PCR amplification 47 ERSA laboratory 47 Interferometer 47 sulfide bearing 47 magnetite pyrite 47 photoelectrochemical 47 Laboratoire Expert Inc. 47 copper Cu 47 caustic fusion 47 NQ diamond drill 47 pulp duplicates 47 microcavity 47 x ray crystallographic 47 Bondar Clegg 47 reaction PCR 47 Laser Ablation 47 Abilab Burkina SARL 47 atomic absorption spectrometer 47 NIRCam 47 nanopowders 47 molybdenum sulphide 47 Maldi 47 Q TOF 47 Beamline 47 acid chloride 47 photocatalysis 47 gas chromatography GC 47 ion implantation 47 TSQ Quantum 47 Surface Plasmon Resonance SPR 47 ISO IEC #:# CAN 47 finite element modeling 47 mineralogical studies 47 copper molybdenum silver 47 massively parallel sequencing 47 magnetic resonance NMR 47 nucleic acid assays 47 HQ diameter 47 ActLabs 47 biophysical techniques 47 flotation tailings 47 Olympus Innov X 47 extraction SPE 47 CaO 47 BSI Inspectorate 47 x ray spectroscopy 47 Nanopore 47 Anisotropy 47 ISO #:# accredited [002] 47 molybdenum Mo 47 mineralogical characterization 47 photoionization 47 quantum mechanically 47 Ray Spectrometer 47 zinc selenide 47 accelerator mass spectrometry 47 ToF SIMS 47 phototransistors 47 sestamibi 47 Synthetic Aperture 47 Electron Microscope 47 pathfinder element 47 ion beam 46 infrared spectroscopy 46 semiconducting 46 Near Infrared 46 #.#gpt [001] 46 Radiometrics 46 Lamothe Showing 46 NQ drill 46 synchrotron x ray 46 scanning tunneling microscopy STM 46 magnetic separator 46 blanks duplicates 46 hypabyssal 46 Fourier transform infrared 46 scanning electron 46 electron beam lithography 46 LTQ Orbitrap Velos 46 chromatographs 46 situ hybridization FISH 46 finely dispersed 46 centrifugation 46 Exoscan 46 protein quantitation 46 polarimetry 46 InAs 46 densitometer 46 analyte 46 γ 46 multivariate statistical 46 proton magnetic resonance 46 dielectric materials 46 chromatograph 46 HTRF R 46 stylus profilers 46 Microscopy AFM 46 weakly anomalous 46 Y Zr 46 heavy fermion 46 ACME Laboratories 46 ChIP chip 46 variably altered 46 scanning electron microscope SEM 46 CIM definitions 46 colorimeters 46 nonlinear optical 46 multiphoton 46 Gemcom GEMS 46 situ measurements 46 Nanoporous 46 mass spectrometric analysis 46 #.#gpt gold [001] 46 gDNA 46 photoacoustic 46 Finite Element Method 46 EBSD 46 anisotropic 46 Chromera 46 Kau# 46 enargite 46 optical coherence tomography OCT 46 Ag Cu Pb 46 DualBeam 46 PANalytical 46 excavator trenches 46 ESI TOF 46 Activation Laboratories Actlabs 46 Liquid Chromatography Mass Spectrometry 46 variography 46 gamma rays emitted 46 photometers 46 ACME Analytical Laboratories 46 linear ion 46 Kulu copper 46 nano patterning 46 Energy Dispersive X 46 probe amplification MLPA 46 dopant 46 infrared spectroscopic 46 nested PCR 46 Predilecta 46 interferometer 46 Electrochemical 46 chromatographic techniques 46 Acme Laboratories 46 reflectometer 46 microspectrophotometer 46 Thermo Scientific Accela 46 INAA 46 leach recoveries 46 accredited laboratory 46 sunt - Gold 46 petrological 46 Transmission Electron Microscopy 46 X ray photoelectron spectroscopy 46 electrospinning 46 Desorption 46 chromated 46 pyrites 46 light scattering DLS 46 dimensional electrophoresis 46 HPLC-Chip/MS 46 elements HREE 46 Fluorine 46 beamline #.#.# 46 frequency combs 46 absorbance 46 RNA extraction 46 monochromators 46 microdiamonds 46 nonequilibrium 46 BLEG 46 grade interpolation 46 liquid chromatographs 46 calorimetry 46 Assaying 46 pyroelectric 46 securely packaged batched 46 confocal microscopy 46 Mastersizer 46 immunohistochemistry IHC 46 semiconductor nanostructures 46 Ab Blaster exerciser 46 rhenium 46 Fluorescence 46 Platinum Pt 46 vibrational modes 46 -# mesh 46 Analytical accuracy 46 Anomalous values 46 photochemical reactions 46 spectrometers 46 SGS laboratories 46 lithogeochemical 46 Ti sapphire laser 46 petrographic analysis 46 TaqMan ® 46 Force Microscopy 46 ALS CHEMEX laboratory 46 moisture analyzer 46 pyrite concentrates 46 electrochemical detection 46 gravimetric method 46 ARPES 46 micromachined 46 multiplex ligation dependent 46 Focused Ion Beam 46 pulsed laser deposition 46 Single Photon Emission Computed 46 photon fluorescence 46 #.#g t Ag [005] 46 gravimetric assay 46 mass spectrometry instrumentation 46 Duplicate samples 46 solariX 46 Western Blotting 46 surface plasmon 46 x ray optics 46 Martison Phosphate Deposit 46 Waters SYNAPT 46 excitation energies 46 Tomography SPECT 46 FeO 46 frequency comb 46 optical lattices 46 ELISA enzyme 46 spectrographs 46 electron multiplying 46 sulphide ores 46 comparative genomic hybridization 45 Metallurgical testwork 45 autosampler 45 crystallographic 45 electroforming 45 Isotopic 45 electrochemical sensor 45 carbides 45 copper alloys 45 Spectrometer 45 fluorescence microscopes 45 sample pulps 45 NDIR 45 pentacene molecule 45 Au Pt Pd 45 Capillary Electrophoresis 45 electrochemical 45 specularite 45 Cu Pb Zn 45 IP geophysical surveying 45 Photometer 45 geostatistical block 45 Suite VIIRS 45 photon microscopy 45 Hydrothermal alteration 45 LANCE Ultra 45 non dispersive infrared 45 Fabry Perot 45 micromechanical 45 Silicon Germanium 45 magnetic susceptibility 45 ALS Chemex preparation 45 alloy castings 45 LightCycler ® 45 trap mass spectrometer 45 magnetic anisotropy 45 QPCR 45 quadrupole 45 Immunohistochemical staining 45 surface plasmon resonance SPR 45 McClelland Laboratories 45 LC MS MS 45 Fourier Transform Infrared 45 radiometric 45 spectrographic 45 Microstructure 45 fluorescent probes 45 High Flux Isotope 45 hematite magnetite 45 Mn Fe 45 nanoliter scale 45 TaqMan R 45 Rhenium Re 45 carbonaceous material 45 Indicated Resource categories 45 Atmospheric Infrared Sounder 45 geophysics prospecting 45 Au eq 45 CCD detector 45 Photolithography 45 Palladium Pd 45 rheometer 45 synchrotron radiation 45 quantitative mass spectrometry 45 geophysical logs 45 iPL 45 parahydrogen 45 crystallites 45 cuvette 45 gene expression microarrays 45 LC MALDI 45 magnesium oxide MgO 45 nanoindentation 45 intramolecular 45 cubic boron nitride 45 gamma ray spectrometry 45 chemiluminescent 45 TOF TOF 45 CSAMT 45 gm tonne 45 antibody antigen 45 Cyanide leach 45 multiplex PCR 45 sulphide flotation 45 antineutrino 45 femtogram 45 transcriptome profiling 45 ELISAs 45 Au t 45 ChIP seq 45 TappingMode 45 electrons positrons 45 Neutral Mass Spectrometer 45 calorimeters 45 immunohistochemical 45 Photonic Crystals 45 corona discharge 45 remelted 45 tandem mass spectrometry 45 electron beams 45 Fermi LAT 45 Accelerator Mass Spectrometry 45 super alloys 45 affinity purification 45 QWIP 45 nanoprobe 45 Plasmonic 45 Dektak 45 MSn 45 Silver Eq 45 XDS VLF EM 45 UPLC MS 45 Sample Preparation 45 transparent conductive oxides 45 Affymetrix GeneChip ® 45 squared ID2 45 TaqMan assay 45 portable XRF analyzer 45 Isotope Ratio 45 fluorination 45 GC MS 45 mass spectrometers 45 bioleaching 45 liquid chromatography LC 45 radiolabeling 45 RT qPCR 45 nano electromechanical systems 45 nanometal 45 JEOL 45 Nambu theories permeate 45 nanoelectromechanical 45 vein stockworks 45 fluorescein 45 X ray spectrometers 45 mesoscopic 45 platinum palladium rhodium 45 ppb Pt 45 Warsash Scientific 45 Gold Equivalent AuEq 45 situ hybridisation 45 Fourier Transform Infrared Spectroscopy 45 quantitative PCR qPCR 45 Dynabeads 45 quantitative RT PCR 45 inelastic scattering 45 Real Viejo 45 ACME Laboratories Lima Peru 45 cryo electron microscopy 45 UHR TOF 45 nanoparticle characterization 45 nanomechanical 45 proteomic analysis 45 Inspectorate Laboratories 45 cyanide extraction 45 immunofluorescence 45 multiwavelength 45 uranophane 45 Polymerase Chain Reaction 45 x ray scattering 45 Stable isotopes 45 photoemission spectroscopy 45 millimeter wavelengths 45 electrical resistivity 45 emission wavelength 45 solvent extraction electrowinning 45 GC FID