北大高等分析1chemicalinstrumentation.ppt

高等分析化学 Chemical Instrumentation The Analysis Concept Some Experiments An Instrument Data Domains Domain Conversion Transducers Example: The Thermocouple Thermocouple1 Thermocouple2 Transfer Functions Example: The pH Meter Reference Standards Example: Double Pan Balance Balance1 Balance2 Signal Noise Signal-to-Noise Performance Characteristics Figure of Merit Precision Accuracy Sensitivity Calibration Sensitivity Analytical Sensitivity Detection Limit Quantitation Limit Linearity Limit Dynamic Range Signal Relationships Selectivity * * Sample For Analysis PROBE Electrons, photons, atoms, molecules, ions, heat RESPONSE Heat, ions, molecules, atoms, photons, electrons Emission of Radiation Emission spectroscopy (X-ray, UV-visible, IR), Fluorescence, Phosphorescence Absorption of Radiation Spectrophotometry (X-ray, UV-visible, IR), Photoacoustic spectroscopy, NMR, ESR, EXAFS, NEXAFS Scattering of Radiation Raman spectroscopy, turbidimetry Diffraction of Radiation Interferometry (FTIR), X-ray diffraction (XRD),Electron diffraction Polarization of Radiation Polarimetry, Optical Rotatory Dispersion (ORD), Circular Dichroism (CD) Mass Gravimetry, Quartz Crystal Nanobalance Mass-to-Charge Ratio Mass Spectrometry Thermal Properties Thermal Gravimetric Analysis (TGA), Differential Scanning Calorimtery (DSC), Differential Thermal Analysis (DTA) Electrical Properties Potentiometry, Coulometry, Voltammetry, Differential Capacitance, Polarography Radioactivity Neutron Activation, Isotope Enrichment ? Controls the applied probe. ? Measures the system’s response. The Physical and Chemical Domain The Analyst’s Domain Instrument Encodes Data Transformation Electrical Domains Non-electrical Domains Physical and Chemical Domain Scale Position Number Charge Current Voltage Power ? An analyst seeks to measure the physical or chemical properties of a system. An instrument creates an electrical signal which represents this datum. ? Data proceeds through the instrument whe