A Radioisotope On-Stream Analyzer for the Mining Industry

1977 ◽  
Vol 21 ◽  
pp. 193-205
Author(s):  
M. Hifetala ◽  
J. Viitanen
Keyword(s):  
Mining Industry ◽  
Sample Cell ◽  
Process Stream ◽  
X Ray ◽  
Radioisotope Source ◽  
Control Chemical ◽  
On Line ◽  
Fluorescence Radiation ◽  
Computer Controlled ◽  
Reference Samples

A distributed on-line analyzing system has been developed for automatic multielemental analysis of mineral slurries and solutions. The elements to be measured should be heavier than potassium. The system consists of measuring probes, a communication loop and a minicomputer with its peripherals. The measuring probe may either be directly immersed into the process stream or it is used with a sample cell in a by-line stream. Measuring probes are located at separate positions in the process. The measurement is based on X-ray fluorescence radiation which is excited with a sealed radioisotope source. The radiation is detected with a sealed high resolution proportional counter without filters. Spectrum stripping is based on reference samples which are measured in a computer controlled sequence in the same geometry as the sample. Thus possible instabilities in gain and resolution are under control. Chemical assays and slurry density are calculated from fluorescence and backscatter intensities. The minicomputer also controls the probes in the system and gives reports.

Computer-Controlled X-Ray and Neutron Diffraction Experiments

1971 ◽  
Vol 15 ◽  
pp. 70-89
Author(s):  
Melvin H. Mueller
Keyword(s):  
High Speed ◽  
Storage Capacity ◽  
Time Sharing ◽  
Large Computer ◽  
X Ray ◽  
Magnetic Structures ◽  
On Line ◽  
Electronic Computers ◽  
Computer Controlled ◽  
Time Sharing System

The use of on-line computers for control and acquisition of data from x-ray and neutron diffractometers has continuously improved and expanded. Systems vary from a small 4K core computer to a time-sharing system with a medium or large computer. The choice of a single time-shared computer or an individual standalone system must be based on one's own particular environment. As large high-speed electronic computers became available, increasingly complex chemical and magnetic structures have been analysed and solved; this has created a demand for rapid, reliable, and versatile means of obtaining diffraction data. Since small computers have been developed at reduced cost and with increased storage capacity, they must be considered for use in diffraction experimentation. Therefore, in x-ray and neutron scattering, small computers are needed for data acquisition and large computers are needed for data analysis.

Computer Controlled X-Ray Diffraction Measurement of Residual Stress

1972 ◽  
Vol 16 ◽  
pp. 344-353 ◽  
Author(s):  
Carol J. Kelly ◽  
E. Eichen
Keyword(s):  
Residual Stress ◽  
Computer Control ◽  
Sample Surface ◽  
Diffraction Measurement ◽  
X Ray Diffraction ◽  
X Ray ◽  
Intensity Measurements ◽  
On Line ◽  
Computer Controlled ◽  
The Difference

AbstractThe system to be described includes hardware and software for the on-line computer control of the X-ray diffraction measurement of residual stress. This determination involves accurately measuring the angles at which a back-reflection line is diffracted, first by diffracting planes parallel to the sample surface, and then by planes at an angle (ψ) to the sample surface. The residual stress is calculated from the difference in the two measured diffraetion angles. The procedure executed by the computer consists of locating the peaks, selecting three angles for collection of X-ray counts, correcting the measured counts, fitting the equi-angular intensity measurements to a three-point parabola, calculating the peak angles, calculating the residual stress from the measured angles and typing a report. This automation has eliminated the tedium of the manual X-ray data accumulation and of the residual stress calculation. The online control has also permitted improvements in the technique not practicable with the manually performed measurement of residual stress.

A Second Derivative Algorithm for Identification of Peaks in Powder Diffraction Patterns

1979 ◽  
Vol 23 ◽  
pp. 287-293 ◽  
Author(s):  
W. N. Schreiner ◽  
Ron Jenkins
Keyword(s):  
Data Analysis ◽  
Large Firm ◽  
X Ray Diffraction ◽  
Widespread Application ◽  
X Ray ◽  
Analysis Techniques ◽  
On Line ◽  
Computer Controlled ◽  
Diffraction Patterns ◽  
Scientific Fields

Modern (>1950) data analysis techniques are commonly applied in many scientific fields but their careful application in other fields, including X-Ray diffraction, has been notably lacking or generally confined to the environment of university research. Perhaps this lack of widespread application in XRD can be blamed on the absence of sophisticated computer controlled instrumentation, and, if this is so, the situation should change rapidly, since today's automated diffractometers are driven by very powerful minicomputers with large firm disks and sophisticated operating systems. In such an environment it is entirely practical to implement, on-line, state-of- the-art data analysis techniques, and in this paper we present one such example.

Resolution Enhancement of X-ray Fluorescence Spectra with a Computerized Multichannel Analyzer

1975 ◽  
Vol 29 (2) ◽  
pp. 171-174 ◽  
Author(s):  
James E. Stewart
Keyword(s):  
Fluorescence Spectra ◽  
Resolution Enhancement ◽  
Real Spectrum ◽  
X Ray ◽  
Multichannel Analyzer ◽  
On Line ◽  
Practical Limit ◽  
Computer Controlled ◽  
Spectral Smoothing ◽  
The Relationship

The relationship between the shape of a real spectrum and the representation of the spectrum that is generated by a linear spectrometer may be described by a Fredholm integral equation. The Burger-van Cittert iterative method for solving the equation is applied to x-ray fluorescence spectra. The extent of enhancement that may be reached is limited by overcorrection in the wings of the recorded lines and the appearance of negative lobes. Reduction in line width of about 20% is a practical limit. There is an inherent increase in noise caused by the enhancement procedure, but this can be minimized by a subsequent spectral smoothing operation. The Burger-van Cittert method is especially suited to on-line treatment of data with a minicomputer or a computer-controlled multichannel analyzer.

A Retrieval System for a Library of Pathology Reports, Slides and Kodachromes

1972 ◽  
Vol 11 (03) ◽  
pp. 152-162 ◽  
Author(s):  
P. GAYNON ◽  
R. L. WONG
Keyword(s):  
Medical Records ◽  
Operative Procedure ◽  
Clinical Findings ◽  
Free Text ◽  
X Ray ◽  
Inverted File ◽  
Natural Language Parsing ◽  
On Line ◽  
Pathology Reports ◽  
Frequency Counts

With the objective of providing easier access to pathology specimens, slides and kodachromes with linkage to x-ray and the remainder of the patient’s medical records, an automated natural language parsing routine, based on dictionary look-up, was written for Surgical Pathology document-pairs, each consisting of a Request for Examination (authored by clinicians) and its corresponding report (authored by pathologists). These documents were input to the system in free-text English without manual editing or coding.Two types of indices were prepared. The first was an »inverted« file, available for on-line retrieval, for display of the content of the document-pairs, frequency counts of cases or listing of cases in table format. Retrievable items are patient’s and specimen’s identification data, date of operation, name of clinician and pathologist, etc. The English content of the operative procedure, clinical findings and pathologic diagnoses can be retrieved through logical combination of key words. The second type of index was a catalog. Three catalog files — »operation«, »clinical«, and »pathology« — were prepared by alphabetization of lines formed by the rotation of phrases, headed by keywords. These keywords were automatically selected and standardized by the parsing routine and the phrases were extracted from each sentence of each input document. Over 2,500 document-pairs have been entered and are currently being utilized for purpose of medical education.

scholarly journals More than XRF Mapping: STEAM (Statistically Tailored Elemental Angle Mapper) a Pioneering Analysis Protocol for Pigment Studies

2021 ◽  
Vol 11 (4) ◽  
pp. 1446
Author(s):  
Jacopo Orsilli ◽  
Anna Galli ◽  
Letizia Bonizzoni ◽  
Michele Caccia
Keyword(s):  
Cultural Heritage ◽  
Element Distribution ◽  
Elemental Distribution ◽  
X Rays ◽  
Spectral Angle Mapper ◽  
X Ray ◽  
Fluorescence Radiation ◽  
Set Up ◽  
Non Destructive ◽  
Analysis Protocol

Among the possible variants of X-Ray Fluorescence (XRF), applications exploiting scanning Macro-XRF (MA-XRF) are lately widespread as they allow the visualization of the element distribution maintaining a non-destructive approach. The surface is scanned with a focused or collimated X-ray beam of millimeters or less: analyzing the emitted fluorescence radiation, also elements present below the surface contribute to the elemental distribution image obtained, due to the penetrative nature of X-rays. The importance of this method in the investigation of historical paintings is so obvious—as the elemental distribution obtained can reveal hidden sub-surface layers, including changes made by the artist, or restorations, without any damage to the object—that recently specific international conferences have been held. The present paper summarizes the advantages and limitations of using MA-XRF considering it as an imaging technique, in synergy with other hyperspectral methods, or combining it with spot investigations. The most recent applications in the cultural Heritage field are taken into account, demonstrating how obtained 2D-XRF maps can be of great help in the diagnostic applied on Cultural Heritage materials. Moreover, a pioneering analysis protocol based on the Spectral Angle Mapper (SAM) algorithm is presented, unifying the MA-XRF standard approach with punctual XRF, exploiting information from the mapped area as a database to extend the comprehension to data outside the scanned region, and working independently from the acquisition set-up. Experimental application on some reference pigment layers and a painting by Giotto are presented as validation of the proposed method.

Synchrotron-based spectroscopy of X-ray channeling through hollow capillary microchannels inside glass plates

2011 ◽  
Vol 19 (1) ◽  
pp. 129-131 ◽  
Author(s):  
M. I. Mazuritskiy
Keyword(s):  
Synchrotron Radiation ◽  
Electronic States ◽  
Capillary Surface ◽  
Glass Capillary ◽  
Hollow Glass ◽  
X Ray ◽  
Microchannel Plates ◽  
Fluorescence Radiation ◽  
Fine Structures ◽  
Channeling Radiation

Here, soft X-ray synchrotron radiation transmitted through microchannel plates is studied experimentally. Fine structures of reflection and XANES SiL-edge spectra detected on the exit of silicon glass microcapillary structures under conditions of total X-ray reflection are presented and analyzed. The phenomenon of the interaction of channeling radiation with unoccupied electronic states and propagation of X-ray fluorescence excited in the microchannels is revealed. Investigations of the interaction of monochromatic radiation with the inner-shell capillary surface and propagation of fluorescence radiation through hollow glass capillary waveguides contribute to the development of novel X-ray focusing devices in the future.

Determination of the GH3.12 protein conformation through HPLC-integrated SAXS measurements combined with X-ray crystallography

2013 ◽  
Vol 69 (10) ◽  
pp. 2072-2080 ◽  
Author(s):  
Adam Round ◽  
Elizabeth Brown ◽  
Romain Marcellin ◽  
Ulrike Kapp ◽  
Corey S. Westfall ◽  
...  
Keyword(s):  
Protein Conformation ◽  
Active Sites ◽  
Solution Structure ◽  
Critical Role ◽  
X Ray ◽  
Hplc Purification ◽  
Closed Conformation ◽  
Terminal Domain ◽  
Redundant Data ◽  
On Line

The combination of protein crystallography and small-angle X-ray scattering (SAXS) provides a powerful method to investigate changes in protein conformation. These complementary structural techniques were used to probe the solution structure of the apo and the ligand-bound forms of theArabidopsis thalianaacyl acid–amido synthetase GH3.12. This enzyme is part of the extensive GH3 family and plays a critical role in the regulation of plant hormones through the formation of amino-acid-conjugated hormone productsviaan ATP-dependent reaction mechanism. The enzyme adopts two distinct C-terminal domain orientations with `open' and `closed' active sites. Previous studies suggested that ATP only binds in the open orientation. Here, the X-ray crystal structure of GH3.12 is presented in the closed conformation in complex with the nonhydrolysable ATP analogue AMPCPP and the substrate salicylate. Using on-line HPLC purification combined with SAXS measurements, the most likely apo and ATP-bound protein conformations in solution were determined. These studies demonstrate that the C-terminal domain is flexible in the apo form and favours the closed conformation upon ATP binding. In addition, these data illustrate the efficacy of on-line HPLC purification integrated into the SAXS sample-handling environment to reliably monitor small changes in protein conformation through the collection of aggregate-free and highly redundant data.

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