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AbstractAbstract
[en] Quantitative analysis of electron microscope autoradiographs aims at extracting the maximum amount of information from ones material. It helps to identify labelled structures from micrographs with low grain densities and can provide numerical estimates for their relative activities. These values will only be estimates because of the low resolution of the technique compared with the resolving power of the electron microscope. The silver grains and the cellular structures they lie over may be well resolved, but it should be remembered that the position of the developed silver grain does not necessarily represent the source of radioactivity in the cell or tissue. This is because the β particles emitted after nuclear disintegration may travel for some distance in the tissue or in the emulsion before a grain is formed. The more energetic the emission the greater this scatter becomes. It is possible, therefore, that a grain lying over one structure may have originated from a nuclear disintegration in a neighbouring one. To analyse the grain distribution it is essential that such possibilities are taken into account by a statistical procedure. Analytical methods are described
Primary Subject
Source
Meeting on techniques in radioautography; Paris, France; 26 Sep - 7 Oct 1975
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Journal Article
Literature Type
Conference
Journal
Journal de Microscopie et de Biologie Cellulaire; v. 27(2-3); p. 185-190
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AbstractAbstract
[en] The measuring methods of optical density essential for X-ray images are briefly described. The value of the medium optical density should lie in that interval (ca. 0.9 ≤ D ≤ 1.25) which is a prerequisite for good detail rendition. The present contribution discusses conditions and methods for determining and adjusting this medium optical density. (orig.)
[de]
Die fuer die Roentgenbilder wesentlichen Messverfahren der optischen Dichte werden kurzgefasst dargestellt. Der Wert der mittleren optischen Dichte von Roentgenaufnahmen sollte in dem Bereich (etwa 0,8 ≤ D ≤ 1,25) liegen, der eine Voraussetzung fuer gute Detailerkennbarkeit des Bildes darstellt. Der Beitrag diskutiert Bedingungen und Verfahren fuer die Bestimmung und Einstellung dieser mittleren Dichte. (orig.)Original Title
Bestimmung der mittleren optischen Dichte von Roentgenaufnahmen
Primary Subject
Source
Stender, H.S.; Stieve, F.E. (eds.); 465 p; ISBN 3-437-11069-1;
; 1986; p. 183-198; Fischer; Stuttgart (Germany, F.R.); Symposium on practice of quality control in X-ray diagnostics; Symposium ueber Praxis der Qualitaetskontrolle in der Roentgendiagnostik; Hannover (Germany, F.R.); 15-16 Oct 1983

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Book
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AbstractAbstract
[en] The testing program described in this report was carried out to study the liquefaction behavior of a clean, uniform, medium sand. Horizontal beds of this sand, 42 inches by 90 inches by 4 inches were prepared by pluviation with a special sand spreader, saturated, and tested in a shaking table system designed for this program, which applied a horizontal cyclic shear stress to the specimens. Specimen size was selected to reduce boundary effects as much as possible. Values of pore pressures and shear strains developed during the tests are presented for sand specimens at relative densities of 54, 68, 82, and 90 percent, and the results interpreted to determine the values of the stress ratio causing liquefaction at the various relative densities
Original Title
Sand
Primary Subject
Source
May 1975; 167 p; NUREG--0027; Available from NTIS., PC A08/MF A01
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Report
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El-Fekey, S.A.; Rofail, N.H.; Farah, M.Y.
Atomic Energy Establishment, Inshas (Egypt). Reactor and Neutron Physics Dept1980
Atomic Energy Establishment, Inshas (Egypt). Reactor and Neutron Physics Dept1980
AbstractAbstract
[en] The objective of this study was to throw some light on ammonium uranates precipitated from uranyl nitrate solution using ammonia or urea. The effect of washing the uranates, thickness of their layers on the trays during subsequent calcination, temperature and duration, on the densities of powders formed during thermal decomposition was studied. (author)
Source
1980; 17 p
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Report
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Thovert, J.-F.; Yousefian, F.; Spanne, P.; Jacquin, C. G.; Adler, P. M.
Funding organisation: (United States)2001
Funding organisation: (United States)2001
AbstractAbstract
[en] The fundamental issue of reconstructing a porous medium is examined anew in this paper, thanks to a sample of low-porosity Fontainebleau sandstone that has been analyzed by computed microtomography. Various geometric properties are determined on the experimental sample. A statistical property, namely, the probability density of the covering radius, is determined. This is used in order to reconstruct a porous medium by means of a Poissonian generation of polydisperse spheres. In a second part, the properties of the real experimental sample and of the reconstructed one are compared. The most important success of the present reconstruction technique is the fact that the numerical sample percolates despite its low porosity. Moreover, other geometrical features and conductivity are found to be in good agreement
Source
Othernumber: PLEEE8000063000006061307000001; 029106PRE; The American Physical Society
Record Type
Journal Article
Journal
Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics; ISSN 1063-651X;
; CODEN PLEEE8; v. 63(6); p. 061307-061307.17

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AbstractAbstract
No abstract available
Primary Subject
Record Type
Journal Article
Journal
Isotopenpraxis; v. 9(8); p. 280-281
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Stolle, W.; Henke, M.
Zentralinstitut fuer Kernforschung, Rossendorf bei Dresden (German Democratic Republic)1983
Zentralinstitut fuer Kernforschung, Rossendorf bei Dresden (German Democratic Republic)1983
AbstractAbstract
[en] The results of sieve analyses may be interpreted in the best manner by approximate functions which permit the exact description of the grain size distributions by two parameters. This fact facilitates the comparison of results of size analyses essentially and enables their graphical representation in form of linear size-distributions curves. The deviations of the linearity refer to irregularities in the powder preparation or in the powder processing. Investigations of UO2-powders by dry sieve analysis have shown that it is possible to classify such powders in the range of grain sizes of more than 63 micrometers, in which specific sieving conditions must be find out for each special material. (author)
Original Title
Theoretische und experimentelle Grundlagen zur Pruefsiebung sowie Untersuchungen zum Siebverhalten von UO2-Pulver
Primary Subject
Source
Feb 1983; 24 p
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Report
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AbstractAbstract
[en] A cloud consisting of a finite number of dust grains in a plasma is considered. It is shown that the absorption of the plasma by the dust grains gives rise to the formation of a plasma flow toward to the cloud. The drag force produced by this flow acts upon the dust grains and counterbalances the electrostatic repulsing force. The distribution of the grain density inside the cloud is determined. The characteristic size of the cloud is estimated as rD3/2/a1/2, where rD is the plasma Debye radius, and a is the size of the dust grains
Primary Subject
Source
Translated from Fizika Plazmy, ISSN 0367-2921, 24, 731-737 (August 1998); (c) 1997 MAIK/Interperiodika; Country of input: International Atomic Energy Agency (IAEA)
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Journal Article
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Translation
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External URLExternal URL
Gouvea, D.; Santilli, C.V.; Varela, J.A.
Proceedings of the 34. Brazilian Congress on Ceramics. v. 11990
Proceedings of the 34. Brazilian Congress on Ceramics. v. 11990
AbstractAbstract
[en] Grain and pore growth are observed during sintering of SnO2 without any densification for temperature up to 15000C. This behaviour is due to mass transport through vapor phase. In order to favor densifying mechanism several concentrations of Nb2O5 were added to SnO2 (1.0, 3.0, 5.0 and 10.0 mol%). Sintering of Nb2O5 doped SnO2 pellets in the range of 1000 to 14500C indicate that Nb2O5 inhibits SnO2 evaporation allowing some densification at 14500C. (author)
[pt]
Grao e crescimento de poro sao observados durante a sinterizacao do SnO2 sem nenhuma densificacao para temperatura acima de 15000C. Este comportamento e devido ao transporte de massa atraves da fase de vapor. Varias concentracoes de Nb2O5 foram adicionadas ao SnO2 (1.0, 3.0, 5.0 e 10.0 mol%). A sinterizacao do Nb2O5 dopado com pastilhas SnO2 na faixa de 1000 ate 14500C indica que Nb2O5 inibe a evaporacao SnO2 permitindo algumas densificacoes a 14500C. (C.G.C.)Original Title
Mecanismos de sinterizacao de compactos de SnO2 dopado com Nb2O5
Primary Subject
Source
Associacao Brasileira de Ceramica, Sao Paulo, SP (Brazil); 341 p; 1990; p. 176-180; 34. Brazilian Congress on Ceramics; Blumenau, SC (Brazil); 20-23 May 1990
Record Type
Miscellaneous
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Lorber, H.W.
EG and G, Inc., Las Vegas, Nev. (USA)1970
EG and G, Inc., Las Vegas, Nev. (USA)1970
AbstractAbstract
No abstract available
Source
14 Oct 1970; 32 p
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Report
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