Application of the Modified Snyder's Program for the Data Processing of an Automated X-Ray Powder Diffractometer

1981 ◽  
Vol 25 ◽  
pp. 261-265
Author(s):  
G. Platbrood ◽  
J. M. Quitin ◽  
H. Barten

X-ray diffraction analysis is an excellent analytical tool. But if a certain quality of the results is needed or if solutions of analytical problems are to be obtained in a short time period, the X-ray diffractometer must be automated and the spectra reduced with dedicated algorithms.In LABORELEC, three programs are principally used to solve the problems encountered in the X-ray diffraction analysis: a modified program given by R. L. Snyder; the search/match G. G. Johnson program (last version); and the POWD5 program.

2021 ◽  
pp. 174751982098472
Author(s):  
Lalmi Khier ◽  
Lakel Abdelghani ◽  
Belahssen Okba ◽  
Djamel Maouche ◽  
Lakel Said

Kaolin M1 and M2 studied by X-ray diffraction focus on the mullite phase, which is the main phase present in both products. The Williamson–Hall and Warren–Averbach methods for determining the crystallite size and microstrains of integral breadth β are calculated by the FullProf program. The integral breadth ( β) is a mixture resulting from the microstrains and size effect, so this should be taken into account during the calculation. The Williamson–Hall chart determines whether the sample is affected by grain size or microstrain. It appears very clearly that the principal phase of the various sintered kaolins, mullite, is free from internal microstrains. It is the case of the mixtures fritted at low temperature (1200 °C) during 1 h and also the case of the mixtures of the type chamotte cooks with 1350 °C during very long times (several weeks). This result is very significant as it gives an element of explanation to a very significant quality of mullite: its mechanical resistance during uses at high temperature remains.


2007 ◽  
Vol 567-568 ◽  
pp. 237-240
Author(s):  
Galina Gosmanová ◽  
Ivo Kraus ◽  
Michal Kolega ◽  
Věra Vrtílková

The results of X-ray diffraction analysis of macroscopic stresses σ and crystallite size D in oxide layers are presented in this contribution. The oxide layers were formed on tubular specimens of Zircaloy 4 and Zr1Nb alloys which were simultaneously oxidized for various times under temperature transient conditions (oxidation in water at 360 °C with a short-time shock in steam at 500 °C). A qualitative relation was outlined between the residual stresses in oxide layers and corrosion kinetics of the alloys under investigation.


Bone ◽  
2006 ◽  
Vol 38 (3) ◽  
pp. 12-13
Author(s):  
M. Kashii ◽  
J. Hashimoto ◽  
T. Nakano ◽  
Y. Umakoshi ◽  
H. Yoshikawa

2021 ◽  
Vol 50 (4) ◽  
pp. 77-84
Author(s):  
Miroslav Mišić ◽  
Sava Stajić ◽  
Marko Petrović ◽  
Vladimir Petrović

X-ray diagnostics has an irreplaceable place in radiology despite other modern diagnostic methods. That is why the production of modern X-ray machines is strategically important for every health system. Serbia has a tradition of over 70 years in the production of X-ray machines. From the first device manufactured in Serbia in 1953, it kept pace with the world in technical and technological terms. X-ray machines were produced by the state company Jugorendgen from Nis. Unfortunately, the company Jugorendgen stopped production before it managed to make a digital X-ray machine. For the past 17 years, these devices have been manufactured by Visaris. Visaris is a private company from Belgrade, which has been developing and manufacturing digital X-ray machines and software systems since 2003. Its importance came to the forefront during the pandemic SARS-CoV-2 infection when the health system of Serbia needed more stationary and mobile X-ray machines in a short time period.


Author(s):  
F. B. Musaev ◽  
S. L. Beletskiy

Introduction. X-ray analysis has been applied for visualizing the internal structure of various objects for over 100 years. However, this method began to be used for assessing the quality of plant seeds only in the early 1980s. The main impediment was a lack of specialized instruments, particularly X-ray sources, that could provide informative images. Advancements in the field of microfocus radiography allowed significant results to be achieved, including the preparation of the National Standard GOST R 596032021 "Agricultural Seeds. Methods of digital radiography".Aim. An analytical review of Russian research studies in the field of X-ray diffraction analysis of plant seeds.Materials and methods. Key stages in the development of microfocus X-ray diffraction analysis of seeds and individual parts of plants for agricultural and other purposes are considered. The design of instruments, including digital ones, created for the implementation of the method are described.Results. In order to obtain informative X-ray diffraction images of plant seeds, which objects are generally characterized by small sizes and small density, the focal spot of the X-ray tube should not exceed several tens of microns under the voltage of not higher than several tens of kilovolts. As a system for visualizing a latent X-ray image, it is preferable to use image receivers based on a screen with a photostimulated phosphor or flat-panel solid-state X-ray detectors. These instruments have been successfully used to identify and describe the radiographic signs of a normal seed and nine main types of defects for 600 plant species.Conclusion. In comparison with the conventional contact radiography, microfocus radiography produces X-ray images of seeds with a projection magnification of the image up to several tens of times. Such images permit highly detailed visualization of the structure of seeds that differ slightly in density.


2012 ◽  
pp. 61-83 ◽  
Author(s):  
M. Ershov

According to the latest forecasts, it will take 10 years for the world economy to get back to “decent shape”. Some more critical estimates suggest that the whole western world will have a “colossal mess” within the next 5–10 years. Regulators of some major countries significantly and over a short time‑period changed their forecasts for the worse which means that uncertainty in the outlook for the future persists. Indeed, the intensive anti‑crisis measures have reduced the severity of the past problems, however the problems themselves have not disappeared. Moreover, some of them have become more intense — the eurocrisis, excessive debts, global liquidity glut against the backdrop of its deficit in some of market segments. As was the case prior to the crisis, derivatives and high‑risk operations with “junk” bonds grow; budget problems — “fiscal cliff” in the US — and other problems worsen. All of the above forces the regulators to take unprecedented (in their scope and nature) steps. Will they be able to tackle the problems which emerge?


1993 ◽  
Vol 58 (12) ◽  
pp. 2924-2935 ◽  
Author(s):  
Jane H. Jones ◽  
Bohumil Štíbr ◽  
John D. Kennedy ◽  
Mark Thornton-Pett

Thermolysis of [8,8-(PMe2Ph)2-nido-8,7-PtCB9H11] in boiling toluene solution results in an elimination of the platinum centre and cluster closure to give the ten-vertex closo species [6-(PMe2Ph)-closo-1-CB9H9] in 85% yield as a colourles air stable solid. The product is characterized by NMR spectroscopy and single-crystal X-ray diffraction analysis. Crystals (from hexane-dichloromethane) are monoclinic, space group P21/c, with a = 903.20(9), b = 1 481.86(11), c = 2 320.0(2) pm, β = 97.860(7)° and Z = 8, and the structure has been refined to R(Rw) = 0.045(0.051) for 3 281 observed reflections with Fo > 2.0σ(Fo). The clean high-yield elimination of a metal centre from a polyhedral metallaborane or metallaheteroborane species is very rare.


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