ENCYCLOPEDIA O FMATERIALS CHARACTERIZATIONC phần 7 pot

... Piream.' HEELS is abso- lutely nondestructive and can be used to obtain information on the chemical com- position, morphology, structure, and phonon modes of the solid surfice. Many polymer ... res- olution fbr light elements, but poor mass resolution for heavy elements. For exam- ple, it is possible to resolve C from 0 or P from Si but it is not possible to resolve W...

Ngày tải lên: 12/08/2014, 14:21

... phonon-assisted photon emission or, more likely, the emission of phonons only. Process 2 produces intrinsic lumi- nescence due to direct recombination between an electron in the conduction ... dispersive mode, for a constant monochromator setting and a scanning elec- tron-beam condition, monochromatic micrographs can be obtained; and when the monochromator is stepped through the .....

Ngày tải lên: 12/08/2014, 14:21

... Atomic Absorption Spectroscopy Atomic Absorption Vapor Phase Decomposition-Atomic Absorption Spectroscopy Graphite Furnace Atomic Absorption Flame Atomic Absorption Auger Electron Spectroscopy ... Loss Spectroscopy High-Resolution Electron Energy-Loss Spectroscopy Reflected Electron Energy-Loss Spectroscopy Reflection Electron Energy-Loss Microscopy Low-Energy Electron-Loss Spectr...

Ngày tải lên: 12/08/2014, 14:21

... is colored, the stage is rotated. Colored, anisotropic materi- als may show pleochroism-a change in color or hue when the orientation with respect to the vibration direction of the polarizer ... microscope. The optical microscope offered the scientist a first look at most samples and could be used to routinely doc- ument the progress of an investigation. As the sophistication of ....

Ngày tải lên: 12/08/2014, 14:21

... it is becoming widely used to monitor homogeneous surface impurities at concentrations down to 10&apos ;o- lO1' atoms/cm2 for heavy metals and 10'2-10'3 atoms/cm2 for elements ... resolution also should be noted. The spectral resolution of the gratings used to monochromatize synchrotron radiation gets worse as the photon energy gets higher, so the resolution advant...

Ngày tải lên: 12/08/2014, 14:21

... biochemistry, and medicine, where it is known under the general name of fluorometry. In PL of semiconductors, one mon- itors emission from the bottom of the conduction band to the top of ... 7 7 VISIBLE / UV EMISSION, REFLECTION, AND ABSORPTION 7. 1 Photoluminescence, PL 373 7. 2 Modulation Spectroscopy 385 7. 3 Variable Angle Spectroscopic Ellipsometry, VASE 401 7....

Ngày tải lên: 12/08/2014, 14:21

... (in the case of negative ions). Boron, which has an ionization potential of 8.3 eV, looses an electron much more easily than does oxy- gen, which has an ionization potential of 13.6 eV, ... The posrioiization methods are: electron impact ionization, ionization by multiple photon interactions, and ionization by collision with metastable atoms in a plasma. The SNMS methods incorporat...

Ngày tải lên: 12/08/2014, 14:21

... show tungsten isotope patterns for WO+, WO,', and WO3+. Another type of interference in ICPMS is suppression of the formation of ions from trace constituents when a large amount of ... This is avoided by adding oxygen to the plasma, converting it from a reducing environment to an oxidizing one. Carbon dioxide is formed from the carbon. Other modifications include operating ....

Ngày tải lên: 12/08/2014, 14:21

... information on additional applications is directed to the proceedings of the Ion Beam Analysis Conferences' and those from the International Conferences on the Application of Accelerators ... does not provide information on chemical bonding or microscopic structure. Hence, it is often used in conjunction with other techniques that do provide such information, such as ESCA, optic...

Ngày tải lên: 12/08/2014, 14:21

... Emission, PIXE 3 57 VISIBLE/W EMISSION, REFLECTION, AND ABSORPTION 7. 0 Introduction 371 7. 1 Photoluminescence, PL 373 7. 2 Modulation Spectroscopy 385 7. 3 Variable Angle Spectroscopic ... &-Ray) Spectroscopy Wavelength Dispersive X-Ray Spectroscopy X-Ray Absorption Spectroscopy X-Ray Photoelectron Spectroscopy X-Ray Photoemission Spectroscopy Electron Spectros...

Ngày tải lên: 05/03/2014, 16:20