Practice for Preparation of Calibration Solutions for Spectrophotometric and for Spectroscopic Atomic Analysis

10.1520/e1452 ◽  
2004 ◽  
Author(s):  
Keyword(s):  
Atomic Analysis

Atomic Analysis of Guinier-Preston Zones in Al-1.7 at% Cu

1996 ◽  
Vol 217-222 ◽  
pp. 701-706
Author(s):  
B. Jouffrey ◽  
Miroslav Karlík ◽  
Dominique François
Keyword(s):  
Atomic Analysis

Opacity and atomic analysis of double pulse laser ablated Li plasma

2014 ◽  
Vol 89 (9) ◽  
pp. 095604
Author(s):  
V Sivakumaran ◽  
H C Joshi ◽  
Ajai Kumar
Keyword(s):  
Pulse Laser ◽  
Double Pulse ◽  
Atomic Analysis ◽  
Double Pulse Laser

scholarly journals The sensitivity of atomic analysis by X-rays

1932 ◽  
Vol 135 (828) ◽  
pp. 637-656 ◽  
Keyword(s):  
Atomic Number ◽  
Target Material ◽  
High Sensitivity ◽  
Major Constituent ◽  
X Rays ◽  
Depth Of Penetration ◽  
X Ray ◽  
Constituent Element ◽  
The Difference ◽  
Atomic Analysis

In a previous paper it was shown that 0·0007 per cent, of 29 Cu and 0·0003 per cent, of 26 Fe could be detected in 30 Zn by atomic analysis by X-ray spectroscopy. This sensitivity is greater than that which was claimed by Noddack, Tacke, and Berg, who set the limit at about 0·1 per cent, for non-metals, and by Hevesy, who stated it to be about 0·01 per cent, for an element present in an alloy. It was later suggested by Hevesy that the high value of the sensitivity which we found might result from the fact that some of the alloys we had used were composed of elements of almost equal atomic number, and that the sensitivity would be smaller for a constituent of low atomic number mixed with a major constituent of high atomic number. To elucidate these disagreements we have made further observations of the sensitivity with elements of different atomic number and have investigated the conditions which can influence the sensitivity. The Factors Determining Sensitivity . The detection of one element in a mixture of elements depends upon the identification of its K or L lines in the general spectrum emitted by the mixture under examination. The intensity with which these lines are excited in the target (“excited intensity”) is proportional to the number of atoms of the constituent element excited, i. e ., to its concentration and to the volume of the target in which the cathode ray energy is absorbed. The depth of penetration of the cathode rays is determined by the density of the target material and by their velocity ( i. e ., by the voltage applied to the X-ray tube). Schonland has shown that the range of homogeneous cathode rays in different elements, expressed as a mass per unit area, is approximately constant and is independent of the atomic number of the absorbing element. When their velocity is increased, the cathode rays will penetrate to a greater depth, and therefore a greater number of atoms of all constituents will be ionised. This will increase the “excited intensity” of the lines due to the particular constituent sought equally with those lines of the other elements present. The intensity of a line further depends upon the difference between the voltage applied to the X-ray tube and that necessary to excite the series. For these reasons, a high applied voltage is required for a high sensitivity.

Atomic analysis and knoop hardness measurement of the cavity floor prepared by Er,Cr:YSGG laser irradiation in vitro

2003 ◽  
Vol 30 (5) ◽  
pp. 515-521 ◽  
Author(s):  
M. Hossain ◽  
Y. Nakamura ◽  
Y. Tamaki ◽  
Y. Yamada ◽  
Y. Murakami ◽  
...  
Keyword(s):  
Laser Irradiation ◽  
Hardness Measurement ◽  
Knoop Hardness ◽  
Atomic Analysis ◽  
Cavity Floor

Molecular and atomic analysis of uranium complexes formed by three eco-types of Acidithiobacillus ferrooxidans

2002 ◽  
Vol 30 (4) ◽  
pp. 669-672 ◽  
Author(s):  
M. Merroun ◽  
C. Hennig ◽  
A. Rossberg ◽  
G. Geipel ◽  
T. Reich ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Acidithiobacillus Ferrooxidans ◽  
Energy Dispersive ◽  
Bacterial Cells ◽  
X Ray ◽  
Uranium Complexes ◽  
Transmission Electron ◽  
Polyphosphate Bodies ◽  
Atomic Analysis

A combination of EXAFS, transmission electron microscopy and energy-dispersive X-ray was used to conduct a molecular and atomic analysis of the uranium complexes formed by Acidithiobacillus ferrooxidans. The results demonstrate that this bacterium accumulates uranium as phosphate compounds. We suggest that at toxic levels when the uranium enters the bacterial cells, A. ferrooxidans can detoxify and efflux this metal by a process in which its polyphosphate bodies are involved.

scholarly journals Structure of catalase determined by MicroED

eLife ◽  
2014 ◽  
Vol 3 ◽  
Author(s):  
Brent L Nannenga ◽  
Dan Shi ◽  
Johan Hattne ◽  
Francis E Reyes ◽  
Tamir Gonen
Keyword(s):  
Structure Determination ◽  
Three Dimensional ◽  
Bovine Liver ◽  
Electron Crystallography ◽  
X Ray ◽  
X Ray Crystallography ◽  
Continuous Rotation ◽  
Bovine Liver Catalase ◽  
Diffraction Patterns ◽  
Atomic Analysis

MicroED is a recently developed method that uses electron diffraction for structure determination from very small three-dimensional crystals of biological material. Previously we used a series of still diffraction patterns to determine the structure of lysozyme at 2.9 Å resolution with MicroED (<xref ref-type="bibr" rid="bib26">Shi et al., 2013</xref>). Here we present the structure of bovine liver catalase determined from a single crystal at 3.2 Å resolution by MicroED. The data were collected by continuous rotation of the sample under constant exposure and were processed and refined using standard programs for X-ray crystallography. The ability of MicroED to determine the structure of bovine liver catalase, a protein that has long resisted atomic analysis by traditional electron crystallography, demonstrates the potential of this method for structure determination.

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