RESUMO
The growth, composition and structure of sandwich structures (Fe-rich layer/Si-rich layer/Fe-rich silicide layer) grown on a Si(111) surface were studied by a few complementary microscopic and spectroscopic techniques with high spatial resolution. Intermixing at the Fe/Si and Si/Fe interfaces is demonstrated. Fe-rich layers grown directly on the Si(111) surface are crystalline and have abrupt but rough interfaces at both sides. The succeeding layers are disordered and their interfaces are fuzzy. The distributions of Fe and Si within the layers are laterally non-uniform. The reproducible fabrication of thin non-magnetic silicide spacers of predetermined thickness is demonstrated. Sandwich structures with such spacers exhibit exchange coupling between ferromagnetic Fe-rich layers.
Assuntos
Peixes/fisiologia , Intestinos/inervação , Neurônios/metabolismo , Óxido Nítrico/fisiologia , Sistema Nervoso Simpático/metabolismo , Animais , Mucosa Intestinal/metabolismo , Intestinos/anatomia & histologia , Músculo Liso/anatomia & histologia , Músculo Liso/lesões , Músculo Liso/metabolismo , NADP/metabolismo , Óxido Nítrico/metabolismoRESUMO
This investigation was aimed at the study of distribution, localization and morphological peculiarities of NO-ergic cells and fibers in the digestive tract of Japanese anchovy Engraulis japonicus. Using the histochemical method developed by B.T. Hope and S.R. Vincent (1989), NO-ergic cells and fibers were demonstrated in the intermuscular plexus and in the circular layer of the muscular tunic in all the digestive tract organs studied. Single No-ergic cells were located in the longitudinal layer of the muscular tunic in the esophagus and stomach. In the submucosal plexus NO-ergic neurons were detected only in the stomach. The greatest density of NO-ergic cell distribution was characteristic to the posterior portion of the intestine and stomach.
