Histochemical, ultrastructural and X-ray microprobe analytical studies of localization of calcium in the mucous lining of the rat duodenum

1988 ◽  
Vol 89 (5) ◽  
pp. 429-436 ◽  
Author(s):  
Y. Takano ◽  
M. Akai
1984 ◽  
Vol 222 (1229) ◽  
pp. 427-438 ◽  

Silicified macrohairs from mature and immature lemmas of the grass Phalaris canariensis L. have been studied by scanning (s.e.m.) and transmission electron microscopy (t.e.m.) and energy dispersive X-ray analysis (e.d.X.a.) at various times after emergence of the inflorescence. Within the macrohairs a variety of morphologies of silica particles was observed. E.d.X.a. revealed the time-dependent concentrations in the macrohairs of the elements K, Cl, P, and S, in addition to Si. Much lower levels of these elements were found in highly silicified mature macrohairs than in the immature macrohairs. It is proposed that the hairs are silicified under strict cellular control.


1997 ◽  
Vol 07 (03n04) ◽  
pp. 117-133 ◽  
Author(s):  
T. Tadic ◽  
Y. Mokuno ◽  
Y. Horino ◽  
M. Jaksic

Numerical calculations of the effect of the finite dimensions and orientations of source and crystal are presented for plane and von Hamos Bragg crystal spectrometers for PIXE analysis, combined with a position sensitive (X-ray) detector. Analytical studies of all effects are provided. It is shown that some parameters can produce line shifts and asymmetries. A numerical model for an X-ray diffraction ray-tracing procedure for a crystal Bragg spectrometer is described.


Author(s):  
Takashi Makita

Alkaline phosphatase activity (ALP-ase) can be localized both over the brush border and on the lateral wall of the duodenal columnar epithelium. (Figs.1,2). Dense precipitate can also be observed on or in the mucus ‘bodies’present on the luminal surface. (Figs.3,4). In order to find out whether it is real phosphatase reaction product(lead phosphate) or not, unstained semi-thin sections (3-500 nm) of glutaraldehyde- fixed tissue, were subjected to X-ray microanalysis, after being incubated in an appropriate substrate medium (Mayahara's lead citrate method), post-fixed in buffered OsO4, and embedded in Spurr resin. A scanning transmission electron micrograph(STEM) was first taken at 25-50 kv(JEOL 50A SEM or 100 C TEM),after which the section was analysed by either a wavelength dispersive detector attached to the SEM or an energy dispersive type enfaced to the TEM at 40-60 kv.


2011 ◽  
Vol 66 (11) ◽  
pp. 1101-1106 ◽  
Author(s):  
Ihor Muts ◽  
Ute Ch. Rodewald ◽  
Vasyl’ I. Zaremba ◽  
Rainer Pöttgen

The orthorhombic indide Sr5Au13.5In8.5 was obtained during phase-analytical studies of the Sr-Au-In system. This new indide is formed upon melting of the elements in a sealed tantalum tube. Sr5Au13.5In8.5 was characterized on the basis of powder and single-crystal X-ray diffraction: Pmmn, a = 476.37(9), b = 2927.5(9), c = 894.9(2) pm, wR2 = 0.056, 2355 F2 values, 87 variables. The structure is of a new type. The gold and indium atoms build up a complex three-dimensional [Au13.5In8.5] polyanionic network in which the strontium atoms fill channels which extend in the a direction. One site within the polyanion shows Au/In mixing. The Sr5Au13.5In8.5 structure is composed of SrAu3In3 -and SrAu-related slabs


1976 ◽  
Vol 21 (1) ◽  
pp. 45-55
Author(s):  
F. N. Ghadially ◽  
N. K. Yong
Keyword(s):  
X Ray ◽  

1996 ◽  
Author(s):  
Shyam P. Keshavmurthy ◽  
Edward T. Dugan ◽  
Joseph C. Wehlburg ◽  
Alan M. Jacobs

1994 ◽  
Vol 144 ◽  
pp. 275-277
Author(s):  
M. Karlický ◽  
J. C. Hénoux

AbstractUsing a new ID hybrid model of the electron bombardment in flare loops, we study not only the evolution of densities, plasma velocities and temperatures in the loop, but also the temporal and spatial evolution of hard X-ray emission. In the present paper a continuous bombardment by electrons isotropically accelerated at the top of flare loop with a power-law injection distribution function is considered. The computations include the effects of the return-current that reduces significantly the depth of the chromospheric layer which is evaporated. The present modelling is made with superthermal electron parameters corresponding to the classical resistivity regime for an input energy flux of superthermal electrons of 109erg cm−2s−1. It was found that due to the electron bombardment the two chromospheric evaporation waves are generated at both feet of the loop and they propagate up to the top, where they collide and cause temporary density and hard X-ray enhancements.


1994 ◽  
Vol 144 ◽  
pp. 1-9
Author(s):  
A. H. Gabriel

The development of the physics of the solar atmosphere during the last 50 years has been greatly influenced by the increasing capability of observations made from space. Access to images and spectra of the hotter plasma in the UV, XUV and X-ray regions provided a major advance over the few coronal forbidden lines seen in the visible and enabled the cooler chromospheric and photospheric plasma to be seen in its proper perspective, as part of a total system. In this way space observations have stimulated new and important advances, not only in space but also in ground-based observations and theoretical modelling, so that today we find a well-balanced harmony between the three techniques.


Sign in / Sign up

Export Citation Format

Share Document