A double Faraday cup attachment for relative intensity measurements on an electron microscope

1982 ◽  
Vol 15 (10) ◽  
pp. 988-990 ◽  
Author(s):  
T A McMath ◽  
A E Curzon ◽  
R F Frindt
Keyword(s):  
Electron Microscope ◽  
Relative Intensity ◽  
Faraday Cup ◽  
Intensity Measurements

Thickness and composition determinations from T.E.M. specimens using both x-ray and backscattered electron data

1984 ◽  
Vol 42 ◽  
pp. 576-577
Author(s):  
M.D. Ball ◽  
H. Lagace ◽  
M.C. Thornton
Keyword(s):  
Electron Microscope ◽  
Atomic Number ◽  
Transmission Electron Microscope ◽  
Convenient Method ◽  
Flow Chart ◽  
X Ray ◽  
Intensity Measurements ◽  
Transmission Electron ◽  
Electron Intensity ◽  
Backscattered Electron

The backscattered electron coefficient η for transmission electron microscope specimens depends on both the atomic number Z and the thickness t. Hence for specimens of known atomic number, the thickness can be determined from backscattered electron coefficient measurements. This work describes a simple and convenient method of estimating the thickness and the corrected composition of areas of uncertain atomic number by combining x-ray microanalysis and backscattered electron intensity measurements.The method is best described in terms of the flow chart shown In Figure 1. Having selected a feature of interest, x-ray microanalysis data is recorded and used to estimate the composition. At this stage thickness corrections for absorption and fluorescence are not performed.

Raman Addition Spectroscopy with a Rotating Cell

1975 ◽  
Vol 29 (5) ◽  
pp. 386-389 ◽  
Author(s):  
Arthur K. Covington ◽  
Jennifer M. Thain
Keyword(s):  
Raman Spectroscopy ◽  
Raman Spectra ◽  
Relative Intensity ◽  
Internal Standard ◽  
Laser Raman Spectroscopy ◽  
New Technique ◽  
Reference Substance ◽  
Laser Raman ◽  
Intensity Measurements ◽  
A New Technique

A new technique is described for obtaining quantitative relative intensity measurements, in the study of solution equilibria by laser-Raman spectroscopy, without the necessity for adding an internal standard to the sample. A rotating cylindrical double cell with separate compartments for sample and reference is used to superimpose the Raman spectra of sample and reference and hence avoid any uncertainties arising from the displacement of the equilibrium by reference substance addition.

Nanocrystallite model for amorphous calcium carbonate

2014 ◽  
Vol 47 (5) ◽  
pp. 1651-1657 ◽  
Author(s):  
P. Rez ◽  
S. Sinha ◽  
A. Gal
Keyword(s):  
Electron Microscope ◽  
Calcium Carbonate ◽  
Electron Diffraction ◽  
Relative Intensity ◽  
Ir Spectrum ◽  
X Rays ◽  
High Angle ◽  
Amorphous Calcium Carbonate ◽  
Optical Birefringence ◽  
X Ray

Amorphous calcium carbonate phases, either synthesized artificially or generated biogenically, can be identified from broadened peaks in X-ray or electron diffraction profiles. It is conceivable that randomly oriented nanocrystals, approximately 1 nm in size, could give rise to coherent diffraction profiles that are characterized as amorphous. The coherent diffraction profiles for 200 keV electrons, as might be used in an electron microscope, and Cu Kα X-rays were calculated for needle-shaped calcite crystals bounded by \{ {11\overline 21}\} facets and rhomb-shaped crystals bounded by \{ {10\overline 14} \} facets. Crystals of about 1.0 nm in size gave a profile that is consistent with the X-ray measurements of amorphous calcium carbonate. The relative intensity of high-angle broadened peaks and changes in the IR spectrum are best explained by disorder in the nanocrystallites. The presence of randomly oriented nanocrystallites also explains the lack of optical birefringence.

Relative Intensity Measurements in Microwave Spectroscopy

1963 ◽  
Vol 34 (8) ◽  
pp. 901-907 ◽  
Author(s):  
Alan S. Esbitt ◽  
E. Bright Wilson
Keyword(s):  
Relative Intensity ◽  
Microwave Spectroscopy ◽  
Intensity Measurements

LFluorescent X-Ray Relative-Intensity Measurements

1972 ◽  
Vol 5 (4) ◽  
pp. 1587-1591 ◽  
Author(s):  
J. H. McCrary ◽  
L. V. Singman ◽  
L. H. Ziegler ◽  
L. D. Looney ◽  
C. M. Edmonds ◽  
...  
Keyword(s):  
Relative Intensity ◽  
X Ray ◽  
Intensity Measurements

Microwave Spectrum of Cyclohexene Sulfide

1973 ◽  
Vol 51 (4) ◽  
pp. 529-532 ◽  
Author(s):  
R. Kewley
Keyword(s):  
Excited States ◽  
Relative Intensity ◽  
Vibrational State ◽  
Heavy Atom ◽  
Microwave Spectrum ◽  
Cyclohexene Oxide ◽  
Rotational Constants ◽  
Ground Vibrational State ◽  
Intensity Measurements

The microwave spectrum of cyclohexene sulfide (7-thiabicycIo[4,1,0]heptane) has been investigated in the 26.5–40 GHz region. R-branch lines due to both a- and c-type transitions have been assigned for the ground vibrational state and for the first excited states of the ring bending and ring twisting modes. From relative intensity measurements the frequencies of these two modes are estimated as: vbend = 115 ± 20 cm−1 and vtwist = 200 ± 60 cm−1. The rotational constants for the ground vibrational state are (in MHz): A = 3512.086 ± 0.010, B = 2057.969 ± 0.003, and C = 1623.023 ± 0.003. These values are consistent with a twisted half chair structure for the heavy atom skeleton of cyclohexene sulfide, similar to that of cyclohexene oxide.

Correlation of Intracellular Calcium Measurements Using X-Ray Microanalysis and Fluorescence Microscopy Techniques

1989 ◽  
Vol 47 ◽  
pp. 898-899
Author(s):  
H.K. Hagler
Keyword(s):  
Electron Microscope ◽  
Dry Weight ◽  
Elemental Content ◽  
X Ray ◽  
Intensity Measurements ◽  
Inactive Form ◽  
Freeze Dried ◽  
Total Elemental Content ◽  
Microscopy Techniques ◽  
Irreversible Injury

It is my thought that calcium plays a major role in the development of irreversible cellular injury in the myocardium.There are two basic forms of calcium within the cell, the active, ionized calcium and the inactive form which may be bound to cell proteins or held in storage sites within the cells.The use of energy dispersive x-ray microanalysis in an analytical electron microscope permits the localization and measurement of the total elemental content of subcellular regions of cells. These measurements generally require that the cells be cryofixed , cryosectioned, cryotransfered and freeze dried in the electron microscope. The Hall method of continuum normalization is then used to convert the x-ray intensity measurements into dry weight concentrations.Because the cells have to be cryofixed, it is not possible to follow the development of elemental changes within a single cell over time, thus many cells have to be frozen at different time intervals to measure time dependent changes of irreversible injury and cell death. Thus, selected time points are identified and sampled for x-ray microanalysis.

scholarly journals Retrieval of tropospheric NO<sub>2</sub> using the MAX-DOAS method combined with relative intensity measurements for aerosol correction

2010 ◽  
Vol 3 (5) ◽  
pp. 1287-1305 ◽  
Author(s):  
T. Vlemmix ◽  
A. J. M. Piters ◽  
P. Stammes ◽  
P. Wang ◽  
P. F. Levelt
Keyword(s):  
Boundary Layer ◽  
Relative Intensity ◽  
Trace Gas ◽  
Optical Absorption Spectroscopy ◽  
Data Set ◽  
Intensity Measurements ◽  
Significant Difference ◽  
Tropospheric No2 ◽  
Retrieval Scheme ◽  
Sky Radiance

Abstract. Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) is a technique to measure trace gas amounts in the lower troposphere from ground-based scattered sunlight observations. MAX-DOAS observations are especially suitable for validation of tropospheric trace gas observations from satellite, since they have a representative range of several kilometers, both in the horizontal and in the vertical dimension. A two-step retrieval scheme is presented here, to derive aerosol corrected tropospheric NO2 columns from MAX-DOAS observations. In a first step, boundary layer aerosols, characterized in terms of aerosol optical thickness (AOT), are estimated from relative intensity observations, which are defined as the ratio of the sky radiance at elevation α and the sky radiance in the zenith. Relative intensity measurements have the advantage of a strong dependence on boundary layer AOT and almost no dependence on boundary layer height. In a second step, tropospheric NO2 columns are derived from differential slant columns, based on AOT-dependent air mass factors. This two-step retrieval scheme was applied to cloud free periods in a twelve month data set of observations in De Bilt, The Netherlands. In a comparison with AERONET (Cabauw site) a mean difference in AOT (AERONET minus MAX-DOAS) of −0.01±0.08 was found, and a correlation of 0.85. Tropospheric-NO2 columns were compared with OMI-satellite tropospheric NO2. For ground-based observations restricted to uncertainties below 10%, no significant difference was found, and a correlation of 0.88.

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