Identification of origins of lesser snow geese by X-ray spectrometry

1977 ◽  
Vol 55 (4) ◽  
pp. 718-732 ◽  
Author(s):  
John P. Kelsall ◽  
Roland Burton
Keyword(s):  
Chemical Elements ◽  
Pulse Height ◽  
Silicon Detector ◽  
Discriminant Functions ◽  
Emission Energy ◽  
X Ray ◽  
Snow Geese ◽  
Lesser Snow Geese ◽  
Computer Controlled ◽  
The Times

An attempt to apply computer-controlled. X-ray spectrometric methods for the identification of origins of waterfowl, through the analysis of chemical elements in their primary flight feathers, is described. Materials were gathered from three geographically distinct populations of wild lesser snow geese (Chen caerulescens). They were laundered, dried, and irradiated by 25 mCi (1 Ci = 37 GBq) Americium 241. Chemical spectra were developed using a lithium-drifted silicon detector, and a computer-controlled pulse-height analyzer that provided results in 512 channels of emission energy between about 2.3 and 40 keV. Computer programs were written or adapted to process our data. Multivariate discriminant functions were used (among other techniques) to examine potential significant differences between populations, and between different year classes within one population. Attempts were made to classify unknown feathers through use of discriminant functions. Best results were obtained by measuring the areas under K alpha peaks of emission energy for recognizable chemical elements in the spectra and using those, and the times for analysis, as significant variables. Two other methods of using the data are compared with that method. Efforts to discriminate geographically different populations, and to classify unknowns are encouraging. However, there are residual problems to be dealt with.

Computer Code for Analysing X-Ray Fluorescence Spectra of Airborne Particulate Matter

1979 ◽  
Vol 23 ◽  
pp. 149-156 ◽  
Author(s):  
E.A. Drane ◽  
D.G. Rickel ◽  
W.J. Courtney ◽  
T.G. Dzubay
Keyword(s):  
Atmospheric Aerosols ◽  
Fluorescence Spectra ◽  
Pulse Height ◽  
Silicon Detector ◽  
Airborne Particulate Matter ◽  
Computer Code ◽  
Elemental Content ◽  
X Ray ◽  
Edxrf Analysis ◽  
Fluorescence Spectrometer

During recent years energy dispersive x-ray fluorescence (EDXRF) has been used to measure the elemental content of atmospheric aerosols. The code described here is used to reduce EDXRF data and determine the elemental composition of samples collected on membrane filters. The program has been specifically written for EDXRF analysis of size-fractionated aerosols collected by a dichotomous sampler.The x-ray fluorescence spectrometer used in our laboratory employs a pulsed-mode x-ray tube and a lithium-drifted silicon detector. Pulse-height spectra are produced for elements ranging in atomic number from Z = 13 to Z = 82 (corresponding to an energy range from 1.4 to 32.1 keV). Approximately uniform x-ray production is attained by producing independent spectra from three secondary targets (Ti, Mo, Sm).

Use Of A Solid-State Detector for the Analysis of X-Rays Excited in Silicate Rocks by Alpha-Particle Bombardment

1971 ◽  
Vol 15 ◽  
pp. 388-406 ◽  
Author(s):  
Ernest J. Franzgrote
Keyword(s):  
Alpha Particle ◽  
Particle Bombardment ◽  
Pulse Height ◽  
Silicon Detector ◽  
Alpha Particles ◽  
X Rays ◽  
Solid State Detector ◽  
X Ray ◽  
Alpha Scattering ◽  
Silicate Rocks

The analysis of alpha-excited X-rays has been studied as a possible addition to the alpha-scattering technique used on the Surveyor spacecraft for the first in situ chemical analyses of the lunar surface.Targets of pure elements, simple compounds, and silicate rocks have been exposed to alpha particles and other radiation from a curium-214 source and the resulting X-ray spectra measured by means of a cooled lithium-drifted silicon detector and pulse-height analysis.Alpha-particle bombardment is a simple and efficient means of X-ray excitation for light elements. Useful spectra of silicate rocks may be obtained in a few minutes with a source activity of 50 millicuries, a detector area of 0.1 cm2 and a sample distance of 3 cm. An advantage over electron excitation is the higher characteristic response relative to the bremsstrahlung continuum. Peak-to- background ratios of greater than 100 to 1 have been obtained for elemental targets. Relative efficiencies of X-ray excitation by alpha particles and by X-rays from the curium source have been determined.Resolution of the detector system used is approximately 150 eV for the lighter elements. This is sufficient to resolve the Kα X-rays of the geochemically important elements, Na, Mg, Al, and Si in silicate rocks. Although these and lighter elements are analyzed as well or better by the alpha-scattering and alpha-proton technique, the X-ray mode enables results to be obtained more quickly.The study shows that the addition of an X-ray mode to the alpha-scattering analysis technique would result in a significant improvement in analytical capability for the heavier elements. In particular, important indicators of geochemical differentiation such as K and Ca (which are only marginally separated in an alpha-scattering and alpha-proton analysis) may be determined quantitatively by measuring the alpha-excited X-rays. An X-ray detector is under consideration as an addition to an alpha-scattering instrument now under development for possible use on a Mars-lander mission.

Energy Dispersive Analysis for Adjacent Elements Using Two Single Channel Analyzers

1971 ◽  
Vol 15 ◽  
pp. 197-208
Author(s):  
Hubert K. Chow
Keyword(s):  
Single Channel ◽  
Matrix Effects ◽  
Pulse Height ◽  
Silicon Detector ◽  
Emission Spectra ◽  
Empirical Method ◽  
Energy Dispersive ◽  
Standard Samples ◽  
X Ray ◽  
Adjacent Element

Energy dispersive x-ray analysis has become an extremely useful analytical tool. The technique provides for the direct observation of x-ray emission spectra, eliminating the need for a dispersive crystal. The purpose of this reported investigation was to study the use of the technique with a simple pulse height analyzing system and to develop a routine method for correcting Interferences due to adjacent element spectral overlap and matrix effects.The analyzing system consists of a radioisotope source, a lithium drifted silicon detector, a preamplifier, an amplifier, two single channel analyzers and two digital ratemeters. In order to obtain results suitable for quantative measurement, a two-step empirical method was employed for the correction of peak overlapping and matrix effects. If two peaks in a spectrum overlap at their tails, one can set up a channel width of the analyzer to a region where there are no overlapping pulses. It is then possible to calibrate the ratio of the intensity obtained from this channel to that obtained from the whole peak in its pure state, i.e. without the appearance of a neighbor peak. The actual intensity of the peak in the overlapping spectrum is, therefore, the observed counts multiplied by the ratio. The next step is the correction of matrix effect by means of conventional empirical methods using standard samples. Two types of the samples, Zn-Cu powder mixtures and Ee-Cu in aqueous solutions, were studied to illustrate this method. The usefulness of applying the analyzing system and technique to industrial measurements, either on-line or batch, will also be discussed.

Chemical variability in plumage of wild lesser snow geese

1975 ◽  
Vol 53 (9) ◽  
pp. 1369-1375 ◽  
Author(s):  
John P. Kelsall ◽  
W. J. Pannekoek ◽  
Roland Burton
Keyword(s):  
Chemical Elements ◽  
Analytical Error ◽  
Snow Geese ◽  
Lesser Snow Geese ◽  
Significant Difference ◽  
Chemical Variability ◽  
Left And Right ◽  
Males And Females ◽  
Young Of The Year

This experiment was designed to show whether there were chemical differences within a population of wild lesser snow geese between the plumage of young of the year and older birds, males and females, left and right wings, and among primary flight feathers 2 to 7, inclusive. The chemical elements Na, Ca, K, Cu, Fe, Mg, Mn, Zn, and Si were used as variables. Many points of statistically significant difference were found, some reflecting physiological and metabolic differences associated with sex and growth.Tests for analytical error, due to technique or equipment, showed it to be large. That result emphasizes the need to randomize the order in which samples are run in this sort of work, and the need for adequate numbers of samples.

Some problems in identification of origins of lesser snow geese by chemical profiles

1979 ◽  
Vol 57 (12) ◽  
pp. 2292-2302 ◽  
Author(s):  
John P. Kelsall ◽  
Roland Burton
Keyword(s):  
Great Accuracy ◽  
Small Sample ◽  
Sample Sizes ◽  
X Ray ◽  
Chen Caerulescens ◽  
Snow Geese ◽  
Lesser Snow Geese ◽  
Chemical Profiles ◽  
Small Sample Sizes ◽  
Work Done

Results are reported of experimental work done to clarify problems and unknowns involved in identifying origins of lesser snow geese through computer-controlled, X-ray spectrometric analyses of primary flight feathers. Materials from wild and captive populations of lesser snow geese (Chen caerulescens caerulescens) were used. The use of an X-ray tube source of irradiation was successfully introduced to previously described techniques. Practical investigation of sample size for the generation of discriminant functions suggests that 30 samples per population are a barely adequate minimum and that 40 or more should be used.Given adequate sample sizes, and suitably different populations, the classification process overrides differences attributable to sex, age, and "Feather year" with great accuracy. With small sample sizes, however, those differences will dampen the accuracy of discrimination and classification, as will increasing numbers of populations. Examination of feathers from a captive flock, maintained for 4 years, shows statistically insignificant sexual differences, significant "within-year" changes in feather chemistry between October and May, and moderately consistent discrimination between year classes. Some of the chemical variables involved in the observed differences are examined.

X-ray Detectors: Pulse Height Shifts, Escape Peaks and Counting Losses

1990 ◽  
Vol 34 ◽  
pp. 319-324
Author(s):  
Michael A. Short
Keyword(s):  
Data Processing ◽  
Pulse Height ◽  
Fluorescence Analysis ◽  
Operating Characteristics ◽  
X Ray ◽  
Computer Based ◽  
Computer Controlled ◽  
Computerized Data Processing

With the ever increasing emphasis on computer-controlled hardware, computerized data processing and computer-based display of results, there is a tendency to forget the operating characteristics of some of the older, more mundane, components of X-ray diffractometers and X-ray fluorescence analysis units. We place our trust in the specifications of the components supplied by the equipment manufacturers and, while usually complete, it nevertheless behooves us to be well aware of the operation of the various hardware components of diffractometers and spectrometers.

Going Nondispersive

1998 ◽  
Vol 4 (S2) ◽  
pp. 162-163
Author(s):  
Kurt F. J. Heinrich
Keyword(s):  
Electron Probe ◽  
Single Channel ◽  
Pulse Height ◽  
Silicon Detector ◽  
X Rays ◽  
X Ray ◽  
Energy Dispersion Spectrometer ◽  
Elementary Analysis ◽  
Geiger Muller Counter ◽  
Pulse Height Analysis

In February 1968 Ray Fitzgerald, Klaus Keil and myself published in Science a communication titled “Solid-State Energy-Dispersion Spectrometer for Electron Microprobe X-ray Analysis”. The authors describe the use of a lithium-drifted silicon detector for the direct identification of x-rays, without a diffracting crystal, in an electron probe. The subject of this paper was to modify profoundly the development of x-ray microanalysis in the years to follow.Pulse-height analysis of gamma rays detected in scintillation counters was widely used at the time. For radiation of energies below 30 keV, gas proportional counters were also employed. In elementary analysis by x-rays the poor energy resolution of these detectors limited the application of such a procedure, although single-channel pulse height analysis was employed as an adjunct to crystal spectrometers.In 1951, Raymond Castaing in his thesis described his invention of the electron probe microanalyzer, created by adding to a transmission electron microscope a curved-crystal spectrometer which focused the x-rays emitted by the specimen into a Geiger-Muller counter.

X-ray mapping without STEM

1994 ◽  
Vol 52 ◽  
pp. 508-509
Author(s):  
Judith M. Brock ◽  
Max T. Otten
Keyword(s):  
Life Science ◽  
Materials Science ◽  
Chemical Elements ◽  
Full Description ◽  
Scanning System ◽  
Elemental Distribution ◽  
X Ray ◽  
Transmission Electron ◽  
Distribution Of Elements ◽  
Made In

A knowledge of the distribution of chemical elements in a specimen is often highly useful. In materials science specimens features such as grain boundaries and precipitates generally force a certain order on mental distribution, so that a single profile away from the boundary or precipitate gives a full description of all relevant data. No such simplicity can be assumed in life science specimens, where elements can occur various combinations and in different concentrations in tissue. In the latter case a two-dimensional elemental-distribution image is required to describe the material adequately. X-ray mapping provides such of the distribution of elements.The big disadvantage of x-ray mapping hitherto has been one requirement: the transmission electron microscope must have the scanning function. In cases where the STEM functionality – to record scanning images using a variety of STEM detectors – is not used, but only x-ray mapping is intended, a significant investment must still be made in the scanning system: electronics that drive the beam, detectors for generating the scanning images, and monitors for displaying and recording the images.

A Calculation real abundance of gaseous elements of the comet PanSTARRS C/2011 S4

2020 ◽  
Vol 18 (45) ◽  
pp. 21-31
Author(s):  
Salman Zaidan Khalaf ◽  
Khaleel Abrahim ◽  
Imad Kassar Akeab
Keyword(s):  
Solar Wind ◽  
Physical Properties ◽  
Atomic Number ◽  
Mathematic Model ◽  
Emission Energy ◽  
X Ray ◽  
The Real

    X-ray emission contains some of the gaseous properties is produced when the particles of the solar wind strike the atmosphere of comet ISON and PanSTARRS Comets. The data collected with NASA Chandra X-ray Observatory of the two comets, C/2012 S1 (also known as Comet ISON) and C/2011 S4 (Comet PanSTARRS) are used in this study.    The real abundance of the observed X-ray spectrum elements has been extracted by a new simple mathematic model. The study found some physical properties of these elements in the comet’s gas such as a relationship between the abundance with emitted energy. The elements that have emission energy (2500-6800) eV, have abundance (0.1-0.15) %, while the elements that have emission energy (850-2500) eV and (6800-9250) eV have abundance (0.2-0.3) %.    The relation between interacted energy and atomic number is form two sets.  The interacted energy of each element is increased as the atomic number increased. This case has been seen in both comets

Processing of granite quarry solid waste into industrial high silica materials using leaching process with HCl concentration variation

2020 ◽  
Vol 11 (2) ◽  
pp. 43-50
Author(s):  
Yusup Hendronursito ◽  
Muhammad Amin ◽  
Slamet Sumardi ◽  
Roniyus Marjunus ◽  
Frista Clarasati ◽  
...  
Keyword(s):  
Particle Size ◽  
Rotational Speed ◽  
Inductively Coupled Plasma ◽  
Chemical Elements ◽  
Silica Content ◽  
X Ray ◽  
Concentration Variation ◽  
Leaching Process ◽  
Hcl Concentration ◽  
Granite Powder

This study was aimed to increase granite's silica content using the leaching process with HCl concentration variation. The granite used in this study came from Lematang, South Lampung. This study aims to determine the effect of variations in HCl concentration, particle size, and rotational speed on the crystalline phase and chemical elements formed in the silica product produced from granite. The HCl concentration variations were 6.0 M, 7.2 M, 8.4 M, and 9.6 M, the variation in particle size used was 270 and 400 mesh. Variations in rotational speed during leaching were 500 and 750 rpm. Granite powder was calcined at 1000 ºC for 2 hours. Characterization was performed using X-Ray Fluorescence (XRF), X-Ray Diffraction (XRD), and Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP- OES). The results showed that the silica content increased with increasing HCl concentration, the finer the particle size, and the higher the rotational speed. XRF analysis showed that the silica with the highest purity was leached with 9.6 HCl with a particle size of 400 mesh and a rotational speed of of 750 rpm, which was 73.49%. Based on the results above, by leaching using HCl, the Si content can increase from before. The XRD diffractogram showed that the granite powder formed the Quartz phase.

Sign in / Sign up

Export Citation Format

Share Document