Introduction and Principles of Analysis of 18 Commonly Used Laboratory Instruments

Ultraviolet absorption spectroscopy, fluorescence spectroscopy, infrared absorption spectroscopy... These are the methods of instrument analysis that we often use in the laboratory. From the abbreviation, analysis principle, spectral representing method, information provided from the perspective of a brief combing.
1. Ultraviolet Absorption Spectrum
Abbreviation: UV;
Analysis Principles: Absorption of ultraviolet light energy, causing the leap of electron energy levels in molecules;
spectrograph: relative absorption of light energy with changes in the wavelength of absorbed light; information provided by
: the position, intensity and shape of absorption peaks, providing information on different electron structures in molecules
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2. Fluorescence spectroscopy
Abbreviation: FS;
Analysis Principle: After being stimulated by electromagnetic radiation, from the lowest single-line excitation state to a single-line baseline state,

emission fluorescence;
3. Infrared Absorption Spectroscopy
Abbreviation: IR;
Analysis Principles: Absorption of infrared light energy, causing vibration of molecules with even-polar moment changes, rotational energy stage leap;
spectrograph: relative transmission light energy changes with transmission light frequency;
provides information: peak position, intensity and shape, provide functional groups or chemical key characteristic vibration frequency.
4. Raman Spectroscopy
Abbreviation: Ram;
Analysis Principles: After absorbing light energy, it causes molecular vibrations with changes in polarization rate, resulting in Raman scattering;
spectrograms are represented by scattering light energy with Raman displacement; and
provides information: the position, intensity, and shape of peaks, providing characteristic vibration frequencies for functional clusters or chemical bonds.
5. MRI spectrometography:
: NMR;
Analysis principle: In the external magnetic field, the nucleus with the nuclear magnetic moment absorbs radio frequency energy to produce the

leap of the nuclear spin energy level;
6. Electron flux resonance spectrometography
abbreviation: ESR;
analysis principle: in the external magnetic field, the molecule does not have a pair of electrons to absorb radio frequency energy, resulting in electron spin energy stage leap,
spectral representing method: absorption of light energy or micro-energy with the strength of the magnetic field changes,
provides information: spectral line position, strength, number of splits and ultra-fine split constant, providing unconstructed electron density, molecular bond properties and geometric configuration information.
7. Mass spectrometography
Abbreviation: MS;
Analysis Principles: Molecules are bombarded by electrons in a vacuum to form ions, separated by different m/e by electromagnetic field;
spectral representation: the relative peak of ions in the form of rod charts varies with m/e;
provides information on the mass and relative peaks of molecular and fragmented ions, providing information on molecular weight, element composition and structure.
8. Gas chromatography
Abbreviation: GC;
Analysis principle: the various parts in the sample are

separated by different distribution coefficients between the flow phase and the fixed phase;
9. Anti-gas chromatography
Abbreviation: IGC;
Analysis Principles: Changes in probe molecular retention depend on the interaction between it and the polymer sample as a fixed phase;
spectral notation: the curve of the value of the probe molecule over the reserved volume with the bar temperature inverse;
provides information: the relationship between the probe molecular retention value and temperature provides the thermodynamic parameters of the polymer.
10. Lysing gas chromatography
Abbreviation: PGC;
analysis principle: polymer materials in a certain conditions of instant lysing, can obtain fragments with certain characteristics;
spectral representing method: the concentration of post-column outflow with the reserved value changes,
provides information: the fingerprint or characteristic fragment peak of the spectral map, the chemical structure and geometry of the character of the polymer.
11. Gel Chromatography
Abbreviation: GPC;
Analysis Principle: When a sample passes through a gel column, it is separated according to the fluid mechanics volume of the molecule, and the large molecules flow out first; the
spectral represents the change of the concentration of the post-column outflow with the reserved value; and the information provided by
: the average molecular weight of the polymer and its distribution.
12. Thermal weight method
Abbreviation: TG;
analysis principle: in temperature control environment, sample weight varies with temperature or time;
spectral representing method: sample weight fraction with temperature or time change curve;
provides information: the steep drop of the curve is the sample weight loss zone, the platform area is the thermal stability zone of the sample.
13. Thermal Difference Analysis
Abbreviation: DTA;
Analysis Principles: Samples and comparators are in the same temperature control environment, due to the difference in thermal conductivity between the two, recording temperature changes with ambient temperature or time;
spectral means: temperature difference with ambient temperature or time change curve;
provides information on polymer thermal transition temperature and various thermal effects.
14. Thermal analysis of the spread scanning volume
Abbreviation: DSC;
analysis principle: samples and comparants in the same temperature control environment, recording the temperature difference of zero, the required energy with the ambient temperature or time changes;
spectral means: heat or its rate of change with the ambient temperature or time of the curve; information provided by
: provides information on polymer thermal transition temperature and various thermal effects
15. static thermal-force analysis
Abbreviation: TMA;
Analysis Principles: the deformation of a sample under constant force changes with temperature or time;
spectral represents: sample deformation with temperature or time curve;
provides information: thermal transition temperature and dynamic state.
16. Dynamic Thermal-Force Analysis
Abbreviation: DMA;
Analysis Principles: The deformation of a sample under the action of periodic changes in external forces varies with temperature; the
spectral represents a modal or tannx curve with temperature;
provides information: thermal transition temperature modulation and tan.
17. Transmission electron microscopy
: TEM;
Analysis principle: scattering, absorption, interference and
diffraction occur when high-energy electron beam penetrates the sample, which causes the formation of lining in the phase plane, showing the image
;
18. Scanning electron microscopy
abbreviation: SEM;
Analysis principle: using electronic technology to detect the action of high-energy electron beams and samples to
produce secondary electrons, backscale electrons, absorption of electrons,
X-rays and other magnified spectra;
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