矿物材料现代测试技术 讲义 - 图文 下载本文

Crystal system:

cubic, tetragonal, orthorhombic, monoclinic, triclinic, hexagonal, triogonal, Symmetry:

plane (m), Center(c), Axles(1,2,3,4,6,3-,6-), Cell Parameters: a, b, c, α, β,? Atomic coordinates:

halite (NaCl) (石盐):

Cl: 0,0,0; ?,0,? ; 0,?,? ; ?,?,0; Na:0,0,?; 0,?0; ?,0,0; ?,?,?.

1.3 Morphological properties (Surface observation) To observe the surface characteristic of the material. Macro – Micro – Super Micro: Macro - by naked eyes.

Micro - by microscope , electron microscope… Super Micro -Scanning tunneling microscopy Atomic force microscopy (AFM) To observe the shape of the particles, their boundary characteristic , in some cases, to observe atom arrangement directly. Generally, the morphological analysis is combined with chemical analysis. It is called micro-region analysis ( both chemical and morphological analysis) 1.4 Analysis of physical and chemical properties Including Thermal, Light, electricity, mechanics, etc. 2. Analyzing Methods 2.1 Chemical Composition 2.1.1 Wet Chemical Analysis: (solid, liquid, gas)--- liquid -----

chemical reaction---

calculating chemical analyzing result

Silicate analysis (including oxides) used for most of the material: (It is called 13 items analysis) SiO2, Al2O3, MgO, FeO, Fe2O3, CaO, K2O, Na2O, MnO, TiO2, P2O5, (H2O)+, (H2O)- percent (%wt), Bulk sample (>2.0g), long period (2 weeks) Generally 2 validating digits after point.

2.1.2 Adsorption spectroscope (Instrument analysis) (solid, liquid, gas)--- liquid -----

Adsorption spectroscopy measuring (different cation adsorbs different wavelength of light)

General concentration (%wt) to micro (ug/g) and also to hint concentration (ng/g) 1 AADS (Atom Adsorption Spectroscope)

Mainly used to determine micro elements (about all elements in the Element Table) From general concentration to micro- concentration ( %wt to ug/g) 2 ICP( Plasma)

Mainly used to determine micro to hint elements (most of the elements in the Table can be determined) (ug/g ---ng/g) 2.1.3 Radiating Spectroscope

Light source --- solid sample--- second light

(the wavelength of the 2nd light changes according to the kind of the elements in the solid sample) --- measuring the 2nd light wavelength, so the kinds and the contents of the elements in the material

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can be determined.

1 x ray Fluorescence Spectroscope (XRF) X射线荧光光谱仪 General to micro concentration (%wt—ug/g). Light source : x ray with continues wave length. Sample: solid. the elements from Na11-U92. but can not distinguish the different charges of the same element: Fe2+ and Fe3+…

2 X ray Photoelectron Spectroscope (XPS) X射线光电子(能)谱仪 Mainly to identify the elements (qualitative). It can distinguish different environments of the same element. O in CO3 and in SiO4 and in H2O. Sample: solid. 3 Isotope Analysis: To determine the ratio of the different isotopes of the same element. Mainly use to determine the age of the sample. Source light: Proton H<100y

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C <50,000 K/Ar<*,000,000

32

Si < *00,000 Rb/Sr,Sm/Nd,

36

Cl <*,000,000 U/Pb<*00,000,000

129

I<*,000,000 2.1.4 Other methods 1 Electron Probe Microscopic analysis( 电子探针(显微分析仪)) EPMA Similar to XRF. But the light source is electron beam, and the analysis only be in a very small region. So it is called micro-region chemical analyzing method). Two kinds of result: Wave disperse Spectroscopy; Energy Disperse Spectroscopy Element range: Na11 - U92

Concentration range: %wt – ug/g

( It also can not distinguish the different charges of the same element, for example: Fe2+ and Fe3+). 2 AES(Auger electron spectroscopy) 俄歇电子谱仪 Llight source: electron beam Condition: vacuum

Similar to EPMA. Using special detector determine the energy of the Auger electron. It can only determine the chemical composition of the very surface layer. (5-20A) 3 Element Analyzer: ( 元素分析仪) Organic analysis

Five elements Quantitative analysis: C, H, O, N, S: 4 Chromatogram (色谱分析)

Two kinds: gas, liquid: (气相色谱仪、液相色谱仪) C,H,O,N,S Qualitative.

Mainly to determine the structure of the organic. For example, the length of the carbon chain. 5 Mossbuare Spectroscope(穆氏保尔谱仪 (穆谱))

To determine the ratio of the different charges of the same element. For example, Fe2+/Fe3+… 6 Backscattering Spectroscope( 背散射电子谱仪) To determine the depth of the elements in the plate sample. 7 Composition analysis:

Bulk analysis, micro-region analysis, surface analysis, Isotope ratio analysis, organic analysis general – micro –hint analysis. Charge analysis

circumstance of elements analysis 2.2 Structure Analysis

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2.2.1 X ray diffraction (XRD) X射线衍射 1 single crystal method: single crystal: 50um - 0.5 mm. Light source: characteristic X ray instrument: four-circle single crystal x ray diffract-meter. 四园单晶x射线衍射仪 Mainly to determine the structure of the new material. In some cases, to determine the crystal parameters 2 Powder crystal method: Sample: powder(<200 mesh) Light source: characteristic x ray

Instrument: powder x ray diffract-meter

Mainly to determine the mineral phase, qualitative or quantitative. In some cases, to determine the structure of the new material.Only valid to the crystal. 2.2.2 Transmission Electron Microscope (TEM) Light source: electron beam Sample: very very thin (0-10nm)

To determine the structure of the sample in a very small region. (nm region) It can directly observe the distribution of the crystal lattice 2.2.3 Infrared Spectroscope (IR): Light source: Infra-red light Sample: solid(powder), liquid, gas. Check the adsorption of the sample to the light from light source. Different chemical bonds can adsorb different wavelength of the light.

To determine the existence of the chemical bonds in the sample (material), also can be used to determine the mineral phase (different mineral has different chemical bonds: their kinds and strength). Adsorption spectroscope.

2.2.4 Laser Raman Spectroscope (RAMAN): Light source: laser with a certain wavelength. Sample: solid, liquid, gas.

When excited by laser, the chemical bonds in the material can radiate a certain wavelength of light. similar with IR. But IR is a kind of adsorption spectroscope. Radiation spectroscope.

To determine the existence of the chemical bonds in the sample (material). 2.3 Surface Morphological Observation Naked eyes: 1* Microscope: 40-400, (1,000 max) Scanning Electron Microscope (SEM) <10,000 sample should be conductive or be made to be conductive. Environment SEM(ESEM) : similar with SEM. But the sample can be conductive or not. Field Emitted SEM (FSEM): <1,000,000 conductive. Transmission Electron Microscope (TEM): <1,000,000 similar with FSEM, but TEM can also do structural analysis. Scanning tunneling microscopy (STM): to observe the arrangement of the atoms (surface layer) directly. Sample should be conductive. Atomic force microscopy(AFM): similar with ASM, but the sample may conductive or not. (SEM) (ESEM) (FSEM) Light source: electron beam. Sample: solid.

when excited by electron beam, the sample can produce the secondary electron. By detecting the secondary electron, the micro-region morphological characteristic can be obtained. (TEM): similar with SEM, but the electron beam transmit the sample (STM): (AFM):

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Using the principle of the electron current (very very small) (ASM) and the force (AFM) between atoms when the atoms are very near. 2.4 physical and chemical properties Thermal Analysis: to determine the changes of sample weight or thermal properties (adsorb heat or radiate heat) under different temperature. Thermo-gravimetry (TG) Derivative Thermo-gravimetry (DTG) Differential Thermal Analysis (DTA)

Homework

试论述学习分析测试技术的意义及在矿物材料中可能的应用。

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