Electron microscopic evaluation of radioactive particles collected near the Chernobyl nuclear reactor

1988 ◽  
Vol 46 ◽  
pp. 964-965
Author(s):  
G.L. Finch ◽  
R.G. Cuddihy ◽  
S.J. Rothenberg ◽  
F.F. Hahn
Keyword(s):  
Health Risks ◽  
Carbon Coating ◽  
Nuclear Reactor ◽  
Sample Surface ◽  
Bulk Sample ◽  
Electron Microscopic ◽  
X Ray ◽  
Small Areas ◽  
Microscopic Evaluation

In April, 1986, an accident at a nuclear reactor near Chernobyl, USSR, resulted in a substantial release of radioactivity into the environment. Characterization of the release is essential to permit estimates of health risks to exposed individuals. This study was conducted to characterize the nature of particles released during the accident and deposited on nearby surfaces.We obtained a sample of wood that was near the reactor at the time of the accident. Autoradiography of the bulk sample (surface area ≈ 125 cm2) showed the presence of about 30 radioactive particles. After microdissection of small areas of the wood matrix, mounting on carbon stubs, and evaporative carbon coating, samples were examined in a scanning electron microscope (SEM; JEOL JSM-35; operated at 20-30 kV in both backscattered [BSE] and secondary electron [SE] modes) equipped with an energy-dispersive x-ray microanalysis system (EDXA; Kevex 5100C). After EDXA, samples were recoated with gold for improved SE imaging.

scholarly journals Analytical electron microscopic evaluation of the effects of paraformaldehyde pretreatment on the reaction of glutaraldehyde with biogenic amines.

1982 ◽  
Vol 30 (5) ◽  
pp. 481-486 ◽  
Author(s):  
R E McClung ◽  
J Wood
Keyword(s):  
Electron Microscopy ◽  
Analytical Electron Microscopy ◽  
Microscopic Level ◽  
Electron Microscopic Level ◽  
Spectrographic Analysis ◽  
Electron Microscopic ◽  
X Ray ◽  
Microscopic Evaluation ◽  
Analytical Electron ◽  
Dense Product

Analytical electron microscopy was used to determine the quantitative effects of paraformaldehyde pretreatment on the formation of the biogenic amine-glutaraldehyde-chrome complex. Pretreatment with paraformaldehyde prevented the glutaraldehyde-chrome reaction with norepinephrine in the rat adrenal medulla. In contrast to the effect of paraformaldehyde on norepinephrine, pretreatment did not prevent the chrome reaction in serotonin-containing argentaffin cells of the gut. X-Ray energy spectrographic analysis revealed a significant decrease in chrome content in the paraformaldehyde treated tissue, but sufficient chrome did react to produce an electron-dense product. Thus by treating tissue with paraformaldehyde prior to the glutaraldehyde chrome procedure, serotonergic sites may be differentiated from catecholaminergic areas at the electron microscopic level.

Characterization of Changes in Properties and Microstructure of Glassy Polymeric Carbon Following Au Ion Irradiation

2009 ◽  
Vol 1215 ◽  
Author(s):  
Malek Amir Abunaemeh ◽  
Mohamed Seif ◽  
Young Yang ◽  
Lumin Wang ◽  
Yanbin Chen ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Nuclear Reactor ◽  
Ion Irradiation ◽  
Pyrolytic Carbon ◽  
X Ray ◽  
Triso Fuel ◽  
Transmission Electron ◽  
Displacement Per Atom ◽  
Polymeric Carbon

AbstractThe TRISO fuel has been used in some of the Generation IV nuclear reactor designs [1,2]. It consists of a fuel kernel of UOx coated with several layers of materials with different functions. Pyrolytic carbon (PyC) is one of the materials in the layers. In this study we investigate the possibility of using Glassy Polymeric Carbon (GPC) as an alternative to PyC. In this work, we are comparing the changes in physical and microstructure properties of GPC after exposure to irradiation fluence of 5 MeV Au equivalent to a 1 displacement per atom (dpa) at samples prepared at 1000, 1500 and 2000°C. The GPC material is manufactured and tested at the Center for Irradiation Materials (CIM) at Alabama A&M University. Transmission electron microscopy (TEM), Rutherford backscattering spectroscopy (RBS), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy were used for the analysis.

The Preparation and Characterization of LiFe0.98Ni0.01Nb0.01PO4/C by Carbon Reduction Route

2012 ◽  
Vol 581-582 ◽  
pp. 570-573
Author(s):  
Jia Feng Zhang ◽  
Bao Zhang ◽  
Xue Yi Guo ◽  
Jian Long Wang ◽  
He Zhang Chen ◽  
...  
Keyword(s):  
Carbon Coating ◽  
Xrd Analysis ◽  
Initial Discharge Capacity ◽  
X Ray Diffraction ◽  
Capacity Retention ◽  
X Ray ◽  
Carbon Reduction ◽  
Initial Discharge ◽  
Structure Morphology

The LiFe0.98Ni0.01Nb0.01PO4/C was synthesized by carbon reduction route using FePO4•2H2O as precursor. The LiFe0.98Ni0.01Nb0.01PO4/C sample was characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and electrochemical measurements. The XRD analysis, SEM and TEM images show that sample has the good crystal structure, morphology and carbon coating. The charge-discharge tests demonstrate that the powder has the better electrochemical properties, with an initial discharge capacity of 164.6 mAh•g−1 at current density of 0.1 C. The capacity retention reaches 99.8% after 100 cycles at 0.1C.

scholarly journals Electrochemical and electron microscopic characterization of Super-P based cathodes for Li–O2 batteries

2013 ◽  
Vol 4 ◽  
pp. 665-670 ◽  
Author(s):  
Mario Marinaro ◽  
Santhana K Eswara Moorthy ◽  
Jörg Bernhard ◽  
Ludwig Jörissen ◽  
Margret Wohlfahrt-Mehrens ◽  
...  
Keyword(s):  
Lithium Salt ◽  
Electrochemical Impedance ◽  
Ex Situ ◽  
Cathode Side ◽  
Li Ion Batteries ◽  
X Ray Diffraction ◽  
Electron Microscopic ◽  
X Ray ◽  
Li Ion

Aprotic rechargeable Li–O2 batteries are currently receiving considerable interest because they can possibly offer significantly higher energy densities than conventional Li-ion batteries. The electrochemical behavior of Li–O2 batteries containing bis(trifluoromethane)sulfonimide lithium salt (LiTFSI)/tetraglyme electrolyte were investigated by galvanostatic cycling and electrochemical impedance spectroscopy measurements. Ex-situ X-ray diffraction and scanning electron microscopy were used to evaluate the formation/dissolution of Li2O2 particles at the cathode side during the operation of Li–O2 cells.

scholarly journals Characterization of Small Areas of Thin-Films by Grazing-Exit Electron Probe X-ray Microanalysis

2002 ◽  
Vol 43 (3) ◽  
pp. 414-416 ◽  
Author(s):  
Kouichi Tsuji ◽  
Zoya Spolnik ◽  
Kazuaki Wagatsuma ◽  
Kesami Saito ◽  
Katsuhiko Asami
Keyword(s):  
Thin Films ◽  
Electron Probe ◽  
X Ray ◽  
Small Areas

scholarly journals Irreversible Structural Transformation of five fold i-AlPdMn Quasicrystals after Ion Bombardment and Annealing

2000 ◽  
Vol 643 ◽  
Author(s):  
F. Schmithüsen ◽  
G. Cappello ◽  
S. Decossas ◽  
G. Torricelli ◽  
T.-L. Lee ◽  
...  
Keyword(s):  
High Resolution ◽  
Structural Transformation ◽  
Bragg Peak ◽  
Normal Incidence ◽  
Ion Bombardment ◽  
Sample Surface ◽  
Bulk Sample ◽  
X Ray Diffraction ◽  
Energy Position ◽  
X Ray

AbstractFive fold i-AlPdMn surface prepared under UHV by ion bombardment and annealing was so far considered to be bulk terminated. This result was substantially based on a quantitative LEED analyses [1]. Analysis of the specular rod in a X ray diffraction experiment at grazing incidence supported this result [2]. We present a new study of this surface by high resolution X ray diffraction at normal incidence. In this Bragg configuration the diffraction peak 18 – 29 for instance is at a photon energy of 2.873keV, the 72 – 116 reflection at 5.725keV. This results in an analyzed thickness of the sample surface of a few micrometers.The surface was cleaned by ion bombardment. During annealing (T≅880K), we clearly observed the progressive disappearance of the initial Bragg peak characteristic of the as cast bulk sample. Conversely a new Bragg peak grows at an energy position shifted by 1eV compared to the position of the original Bragg peak. This is a clear signature for an irreversible structural transformation which takes place on at least the micron thickness. On the transformed surface, both, a LEED pattern and a RHEED pattern, characteristic for a five fold surface were easily obtained.This high resolution experiment (the relative Bragg peak shift is 3ׁ10−4) was reproduced on samples from different initial compositions. This shows that five fold i-AlPdMn surface changes after preparation by ion bombardment and annealing at 900K on a micrometer thickness. This is not consistent with the conclusion that the surface is simply terminated by a cut of the original bulk. We conclude that a reorganization process of the quasicrystalline structure during annealing proceeds in the surface vicinity (probed depth is close to a few microns).

Application Ofthinfilm Method to Electronic Probe Microanalysis (EPMA)

2001 ◽  
Vol 7 (S2) ◽  
pp. 686-687
Author(s):  
Hideyuki Takahashi ◽  
Toshiaki Suzuki ◽  
Charles Nielsen
Keyword(s):  
Thin Film ◽  
Ion Beam ◽  
Sampling Technique ◽  
Soft Materials ◽  
Sample Surface ◽  
Bulk Sample ◽  
Inorganic Materials ◽  
X Ray ◽  
Ray Diffusion ◽  
Area X

Usually, in electron probe microanalysis, the X-ray diffusion range is around lμm on the sample surface. For this reason, the maximum useful magnification of X-ray image seems to be limited to a few thousand times. The X-ray diffusion on the \im order takes place in the bulk sample. However, when a sample is cut to a thin film, it is likely that the X-ray diffusion range will be made smaller, and it is also possible to observe very a narrow area X-ray image at higher magnification. The thin film method is a sampling technique used often in transmission electron microscopy. The microtome method has been applied to organic materials, and the method using focus ion beam (FIB) has been applied to inorganic materials. Takahashi et al. have reported the effectiveness of the microtome application to EPMA of soft materials. in this report, the FIB method was applied to a sampling of inorganic materials in order to obtain high resolution X-ray images of real samples.

X-Ray Microanalysis of Al/Zr Multilayers in the Transmission Electron Microscope

1997 ◽  
Vol 472 ◽  
Author(s):  
M. A. Wall ◽  
T. W. Barbee ◽  
J. Bentley
Keyword(s):  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Electron Probe ◽  
Nanometer Scale ◽  
Line Profiles ◽  
Electron Microscopic ◽  
X Ray ◽  
Transmission Electron ◽  
Interface Layers

ABSTRACTA one-nanometer scale transmission electron microscope electron probe X-ray microanalysis characterization of as-deposited and annealed aluminum - 11.5 at.% zirconium multilayer samples in cross-section synthesized by magnetron sputtering is reported on here. Composition line profiles were acquired across Zr layers in as-deposited material and samples isochronnally annealed in a differential scanning calorimeter to temperatures of 290°C and 485°C. A spatial resolution of approximaty 1.5 to 2.0 nm was achieved in these experiments and will be improved by deconvoluti on of the instrumental electron probe function from the data. The as-deposited structure consisted of crystalline Al and Zr layers with thin amorphous layers at the Al/Zr interfaces. The amorphous interface layers increased in thickness upon annealing to 290°C. Additionally, at 290”C a metastable cubic alloy forms at the Zr deposited on Al interface. Upon heating to 485°C a multilayer of Al and metastable cubic AlxZr1-x phase is formed. The electron microscopic experimental technique, observations and data analysis will be discussed as applied to these multilayered materials.

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