Corrections for the effects of analyzer modulation on peak intensity in derivative Auger spectra

2021 ◽  
Author(s):  
John T. Grant
Keyword(s):  
Peak Intensity ◽  
Auger Spectra

Phase identification from electronic structures by Auger electron spectroscopy

2008 ◽  
Vol 23 (1) ◽  
pp. 83-86 ◽  
Author(s):  
Fuchun Xu ◽  
Duanjun Cai ◽  
Junyong Kang
Keyword(s):  
Auger Electron Spectroscopy ◽  
Electronic Structures ◽  
Electron Spectroscopy ◽  
Auger Electron ◽  
Practical Investigations ◽  
Phase Identification ◽  
Zinc Blende ◽  
Peak Intensity ◽  
Substantial Correlation ◽  
Auger Spectra

A technique of phase identification from the characteristics of electronic structures is established by Auger electron spectroscopy. GaN epilayers in wurtzite and zinc-blende polytypes are used for practical investigations. Auger spectra show phase-dependent energetic shifts and peak intensity variations. Simulation of theoretical spectra reveals the substantial correlation of the Auger line shape with the bonding electronic states. This approach demonstrates the correspondence between electronic structure and atomic structure and hence provides criteria for phase identification.

Resolution Attainable With the Present Day STEM

1973 ◽  
Vol 31 ◽  
pp. 230-231 ◽  
Author(s):  
J. S. Wall ◽  
J. P. Langmore ◽  
H. Isaacson ◽  
A. V. Crewe
Keyword(s):  
Spherical Aberration ◽  
Focal Length ◽  
Incident Beam ◽  
Scanning Transmission Electron Microscope ◽  
Aperture Size ◽  
Magnetic Lens ◽  
Peak Intensity ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
Half Angle

The scanning transmission electron microscope (STEM) constructed by the authors employs a field emission gun and a 1.15 mm focal length magnetic lens to produce a probe on the specimen. The aperture size is chosen to allow one wavelength of spherical aberration at the edge of the objective aperture. Under these conditions the profile of the focused spot is expected to be similar to an Airy intensity distribution with the first zero at the same point but with a peak intensity 80 per cent of that which would be obtained If the lens had no aberration. This condition is attained when the half angle that the incident beam subtends at the specimen, 𝛂 = (4𝛌/Cs)¼

An Analysis of Dissociation of Molecules in a High Resolution Electron Microscope

1973 ◽  
Vol 31 ◽  
pp. 486-487
Author(s):  
Mihir Parikh
Keyword(s):  
Electron Microscope ◽  
High Resolution ◽  
Cross Sections ◽  
Resolving Power ◽  
Peak Intensity ◽  
Molecular Film ◽  
Resolution Electron ◽  
Dissociation Cross Section ◽  
High Resolution Electron Microscope ◽  
The Stability

It is well known that the resolution of bio-molecules in a high resolution electron microscope depends not just on the physical resolving power of the instrument, but also on the stability of these molecules under the electron beam. Experimentally, the damage to the bio-molecules is commo ly monitored by the decrease in the intensity of the diffraction pattern, or more quantitatively by the decrease in the peaks of an energy loss spectrum. In the latter case the exposure, EC, to decrease the peak intensity from IO to I’O can be related to the molecular dissociation cross-section, σD, by EC = ℓn(IO /I’O) /ℓD. Qu ntitative data on damage cross-sections are just being reported, However, the microscopist needs to know the explicit dependence of damage on: (1) the molecular properties, (2) the density and characteristics of the molecular film and that of the support film, if any, (3) the temperature of the molecular film and (4) certain characteristics of the electron microscope used

Design of a UHV STEM for Through-The-Lens Electron Spectroscopy

1990 ◽  
Vol 48 (2) ◽  
pp. 380-381
Author(s):  
A. J. Bleeker ◽  
P. Kruit
Keyword(s):  
Secondary Electron ◽  
High Vacuum ◽  
Secondary Electron Emission ◽  
Auger Spectroscopy ◽  
Scanning Transmission Electron Microscope ◽  
Point Of View ◽  
Ultra High Vacuum ◽  
Scanning Transmission ◽  
Auger Spectra ◽  
Coincidence Measurements

Combining of the high spatial resolution of a Scanning Transmission Electron Microscope and the wealth of information from the secondary electrons and Auger spectra opens up new possibilities for materials research. In a prototype instrument at the Delft University of Technology we have shown that it is possible from the optical point of view to combine STEM and Auger spectroscopy [1]. With an Electron Energy Loss Spectrometer attached to the microscope it also became possible to perform coincidence measurements between the secondary electron signal and the EELS signal. We measured Auger spectra of carbon aluminium and Argon gas showing energy resolutions better than 1eV [2]. The coincidence measurements on carbon with a time resolution of 5 ns yielded basic insight in secondary electron emission processes [3]. However, for serious Auger spectroscopy, the specimen needs to be in Ultra High Vacuum. ( 10−10 Torr ). At this moment a new setup is in its last phase of construction.

HIGH-RESOLUTION AUGER SPECTRA OF Li, Be, B AND C EXCITED IN SINGLE GAS COLLISIONS

1979 ◽  
Vol 40 (C1) ◽  
pp. C1-14-C1-16
Author(s):  
P. Bisgaard ◽  
R. Bruch ◽  
M. Rødbro
Keyword(s):  
High Resolution ◽  
Auger Spectra

Ultrafast laser micro-nano structured superhydrophobic teflon surfaces for enhanced SERS detection via evaporation concentration

2020 ◽  
Vol 9 (1-2) ◽  
pp. 89-100 ◽  
Author(s):  
Xinyu Hu ◽  
Rui Pan ◽  
Mingyong Cai ◽  
Weijian Liu ◽  
Xiao Luo ◽  
...  
Keyword(s):  
Rhodamine 6G ◽  
Optimal Parameter ◽  
Solute Concentration ◽  
Processing Parameter ◽  
Detection Techniques ◽  
Peak Intensity ◽  
Target Analytes ◽  
Sers Detection ◽  
Scanning Path ◽  
Evaporation Concentration

AbstractEvaporation concentration of target analytes dissolved in a water droplet based on superhydrophobic surfaces could be able to break the limits for sensitive trace substance detection techniques (e.g. SERS) and it is promising in the fields such as food safety, eco-pollution, and bioscience. In the present study, polytetrafluoroethylene (PTFE) surfaces were processed by femtosecond laser and the corresponding processing parameter combinations were optimised to obtain surfaces with excellent superhydrophobicity. The optimal parameter combination is: laser power: 6.4 W; scanning spacing: 40 μm; scanning number: 1; and scanning path: 90 degree. For trapping and localising droplets, a tiny square area in the middle of the surface remained unprocessed for each sample. The evaporation and concentration processes of droplets on the optimised surfaces were performed and analyzed, respectively. It is shown that the droplets with targeted solute can successfully collect all solute into the designed trapping areas during evaporation process on our laser fabricated superhydrophobic surface, resulting in detection domains with high solute concentration for SERS characterisation. It is shown that the detected peak intensity of rhodamine 6G with a concentration of 10−6m in SERS characterisation can be obviously enhanced by one or two orders of magnitude on the laser fabricated surfaces compared with that of the unprocessed blank samples.

The distribution of BrKα/RbKα peak intensity ratio in human whole blood samples

1994 ◽  
Vol 42 (3) ◽  
pp. 231-241 ◽  
Author(s):  
C. Shenberg ◽  
S. Spiegel ◽  
S. Chaitchik ◽  
P. Jordan ◽  
M. Kitzis ◽  
...  
Keyword(s):  
Whole Blood ◽  
Intensity Ratio ◽  
Peak Intensity Ratio ◽  
Blood Samples ◽  
Human Whole Blood ◽  
Peak Intensity ◽  
Whole Blood Samples

scholarly journals Morphological, thermal, and thermomechanical properties of cellulose nanocrystals reinforced polylactide/poly [(butylene succinate)-co-adipate] blend composite foams

2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Mpho Phillip Motloung ◽  
Simphiwe Zungu ◽  
Vincent Ojijo ◽  
Jayita Bandyopadhyay ◽  
Suprakas Sinha Ray
Keyword(s):  
Morphological Analysis ◽  
Cell Structure ◽  
Environmentally Friendly ◽  
Processing Technique ◽  
Thermomechanical Properties ◽  
Environmental Concerns ◽  
Butylene Succinate ◽  
Peak Intensity ◽  
Composite Foams ◽  
Reinforcing Agent

Abstract This study examines the influence of cellulose nanocrystal (CN) particles on the morphological, thermal, and thermo-mechanical properties of polylactide (PLA)/poly [(butylene succinate)-co-adipate] (PBSA) blend foams prepared by casting and particulate leaching method using fructose as porogen particles. The morphological analysis showed an interconnected open-cell structure, with porosity above 80%. The crystallinity of the prepared foams was disrupted by the inclusion of CN particles as observed from XRD analyses, which showed a decrease in PLA crystal peak intensity. With regards to neat blend foam, the onset thermal degradation increased with the addition of CN particles, which also increased the thermal stability at 50% weight loss. Furthermore, CN acted as a reinforcing agent in improving the stiffness of the prepared blend foam. Overall, completely environmentally friendly foams were successfully prepared, as a potential material that can replace the current existing foam materials that pose many environmental concerns. However, there is a need to develop an environmentally friendly processing technique.

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