Electron-microscopic investigation of the formation of colloidal beta FeOOH during slow hydrolysis of an aqueous ferric chloride solution at room temperature

1967 ◽  
Vol 215 (1) ◽  
pp. 57-60 ◽  
Author(s):  
R. H. H. Wolf ◽  
M. Wrischer ◽  
J. Šipalo-Žuljević
Keyword(s):  
Ferric Chloride ◽  
Chloride Solution ◽  
Room Temperature ◽  
Ferric Chloride Solution ◽  
Microscopic Investigation ◽  
Electron Microscopic Investigation ◽  
Electron Microscopic ◽  
Hydrolysis Of

scholarly journals Структура и магнитные свойства слоевых нанопроволок из 3d-металлов, полученных методом матричного синтеза

2020 ◽  
Vol 62 (9) ◽  
pp. 1531
Author(s):  
Д.А. Черкасов ◽  
Д.Л. Загорский ◽  
Р.И. Хайбуллин ◽  
А.Э. Муслимов ◽  
И.М. Долуденко
Keyword(s):  
Room Temperature ◽  
Microscopic Investigation ◽  
Electron Microscopic Investigation ◽  
Matrix Synthesis ◽  
Electron Microscopic ◽  
Demagnetizing Field ◽  
Magnetic Layers ◽  
Magnetic Metal ◽  
Galvanic Deposition ◽  
Vibration Magnetometer

Arrays of layered nanowires (NWs) with a diameter of 100 nm consisting of alternating layers of Ni/Cu and Co/Cu were obtained by matrix synthesis based on polyethylene terephthalate track etched membranes. The process of galvanic deposition was studied and the regimes of obtaining of layered nanowires with different thicknesses of magnetic (Ni or Co) and non-magnetic (Cu) components of layers were determined. Electron microscopic investigation was performed to verify regimes of obtaining of layered nanowires and to refine the geometric properties of alternating layers. Using vibration magnetometer, the magnetization curves of the obtained arrays of layered NWs was measured at room temperature for two limiting orientations of the scanning magnetic field: parallel and perpendicular to the growth axis of the NW. It is shown that the magnetic anisotropy of the NW array is determined not only by the chemical composition, but also by the thickness and period of alternating magnetic layers in the NW. Numerical calculations of the dependence of the magnetostatic energy and the magnitude of the demagnetizing field in the synthesized layered NWs on the factor of their filling with a magnetic metal are carried out, which are qualitatively consistent with experimental observations.

Aggregation of clay by the products of iron (III) hydrolysis

Soil Research ◽  
1973 ◽  
Vol 11 (1) ◽  
pp. 75 ◽  
Author(s):  
AV Blackmore
Keyword(s):  
Structure Formation ◽  
Ferric Chloride ◽  
Chloride Solution ◽  
Ferric Chloride Solution ◽  
Normal Dispersion ◽  
Two Phases ◽  
Hydrolysis Of

An attempt has been made to discover the mechanism of iron cementation in clays by comparing the aggregation effected in dispersed pure mineral clay by its exposure to different stages in the active hydrolysis of a ferric chloride solution. Contact of the clay with the early products of the hydrolysis is apparently necessary for the achievement of stable bonding; clay mixed with the gelatinous precipitate formed at the end of the hydrolysis is not stably aggregated, but a combination of these two phases produces aggregates which are particularly resistant to normal dispersion treatment. The results are discussed in terms of the kinetic steps in the hydrolysis of iron(III) solutions, and their implications for structure formation in soils are outlined.

A Scanning Electron Microscopic Investigation of Bonding of Methacryloyloxyalkyl Hydrogen Maleate to Etched Dentin

1990 ◽  
Vol 69 (1) ◽  
pp. 46-50 ◽  
Author(s):  
T. Fukushima ◽  
T. Horibe
Keyword(s):  
Phosphoric Acid ◽  
Acid Solution ◽  
Ferric Chloride Solution ◽  
Microscopic Investigation ◽  
Phosphoric Acid Solution ◽  
Electron Microscopic Investigation ◽  
Electron Microscopic ◽  
Bonding Agents ◽  
Bond Strengths ◽  
Scanning Electron

Three types of methacryloyloxyalkyl hydrogen maleates-2-(methacryloyloxy)ethyl hydrogen maleate (2MEM), 1-(methacryloyloxymethyl)ethyl hydrogen maleate (MMEM), and 1-(methacryloyloxymethyl)propyl hydrogen maleate (MMPM)-were prepared for use as bonding agents. The relationships between the thickness of an acid-proof dentin layer and the bond strength and chemical structure of the synthesized monomers were investigated. The bond strengths of 2MEM/composite system to dentin treated with either 37% phosphoric acid solution or 10% citric acid-3% ferric chloride solution (10-3 solution) were superior to those of the others. The acid-proof dentin layer for all bonding agents containing the synthesized monomers at the resin-dentin interface was clearly visible in a scanning electron microscope, regardless of the types of dentin etching agents used. After treatment of the dentin with the phosphoric acid solution, the layers of 2MEM, MMEM, and MMPM were 5-6 μm, 3-4 μm, and 2-3 μm thick, respectively. When the dentin was treated with the 10-3 solution, the layer for each bonding agent was approximately 1 μm thick.

Light and electron microscopic investigation of adenohypophyses of germfree, food-restricted, and germfree-food restricted aging, male lobund-wistar rats

1988 ◽  
Vol 46 ◽  
pp. 352-353
Author(s):  
G. Ilse ◽  
K. Kovacs ◽  
N. Ryan ◽  
T. Sano ◽  
L. Stefaneanu ◽  
...  
Keyword(s):  
Wistar Rats ◽  
Microscopic Investigation ◽  
Electron Microscopic Investigation ◽  
Aging Male ◽  
Sprague Dawley ◽  
Electron Microscopic ◽  
Sprague Dawley Rats ◽  
Old Rats ◽  
Ad Libitum ◽  
Microscopic Findings

Germfree state and food restriction have been shown to increase life span and delay tumor occurrence in rats. We report here the histologic, immunocytochemical and electron microscopic findings of adenohypophyses of aging, male Lobund-Wistar rats raised at Lobund Laboratories. In our previous study, the morphologic changes in the adenohypophyses of old rats have been extensively investigated by histology, immunocytochemistry and electron microscopy. Lactotroph adenomas were frequent in Long-Evans and Sprague-Dawley rats, whereas gonadotroph adenomas were frequent in Sprague-Dawley and Wistar rats.Male Lobund-Wistar rats were divided into four groups: 1) conventional, which were raised under normal non-germfree environment and received food ad libitum; 2) germfree-food ad libitum; 3) conventional environment-food restricted and 4) germfree-food restricted. The adenohypophyses were removed from 6-month-, 18-month- and 30-month-old rats. For light microscopy, adenohypophyses were fixed in formalin and embedded in paraffin.

An Electron Microscopic Study of the Acute Effects of Hypothalamic Releasing Factors on the Anterior Pituitary Gland

1968 ◽  
Vol 26 ◽  
pp. 232-233
Author(s):  
P.W. Coates ◽  
E.A. Ashby ◽  
L. Krulich ◽  
A. Dhariwal ◽  
S. McCann
Keyword(s):  
Anterior Pituitary ◽  
Microscopic Investigation ◽  
Uranyl Acetate ◽  
Electron Microscopic Investigation ◽  
Electron Microscopic ◽  
Tissue Samples ◽  
Thin Sections ◽  
Dense Membrane ◽  
Membrane Bound ◽  
Releasing Factors

The morphologic effects on somatotrophs of crude sheep hypothalamic extract prepared from stalk-median eminence were studied by electron microscopy in conjunction with concurrently run bioassays performed on the same tissue samples taken from young adult male Sherman rats.Groups were divided into uninjected controls and injected experimentals sacrificed at 5', 15', and 30' after injection. Half of each anterior pituitary was prepared for electron microscopic investigation, the other half for bioassay. Fixation using collidine buffered osmium tetroxide was followed by dehydration and embedment in Maraglas. Uranyl acetate and lead citrate were used as stains. Thin sections were examined in a Philips EM 200.Somatotrophs from uninjected controls appeared as described in the literature (Fig. 1). In addition to other components, these cells contained moderate numbers of spherical, electron-dense, membrane-bound granules approximately 350 millicrons in diameter.

Fine Structural Classification of Chromophobe Adenomas of the Human Pituitary Gland

1975 ◽  
Vol 33 ◽  
pp. 378-379
Author(s):  
K. Kovacs ◽  
E. Horvath
Keyword(s):  
Pituitary Adenomas ◽  
Secretory Activity ◽  
Microscopic Investigation ◽  
Uranyl Acetate ◽  
Electron Microscopic Investigation ◽  
Electron Microscopic ◽  
Human Pituitary ◽  
Cytoplasmic Staining ◽  
Human Pituitary Gland ◽  
Microscopic Features

Chromophobe pituitary adenomas arise from adenohypophysial cells and fail to exhibit cytoplasmic staining with conventional acid or basic dyes by light microscopy. The aim of the present work was to study the electron microscopic features of these tumors, to separate them into distinct entities and to correlate their fine structural appearances with secretory activity.Among 48 surgically removed various pituitary adenomas 30 tumors were found which, based on the tinctorial characteristics of the cytoplasm, corresponded to chromophobe adenomas. For electron microscopic investigation pieces of these tumors were fixed in 2.5 per cent glutaraldehyde in Sorensen's buffer, post fixed in 1 per cent osmium tetroxide in Millonig's buffer, dehydrated in graded ethanol and embedded in Epon 812. Ultrathin sections were stained with uranyl acetate and lead citrate.By electron microscopy it was possible to separate chromophobe adenomas into 3 distinct entities: 1) adenomas consisting of sparsely granulated growth hormone cells (7 cases).

Temporal and spatial interrelationships of confronting cisternae to nuclear envelope

1992 ◽  
Vol 50 (1) ◽  
pp. 930-931
Author(s):  
John R. Palisano
Keyword(s):  
Endoplasmic Reticulum ◽  
Nuclear Envelope ◽  
Tumor Cells ◽  
Hela Cells ◽  
Microscopic Investigation ◽  
Electron Microscopic Investigation ◽  
Serial Sections ◽  
Electron Microscopic ◽  
Fetal Rat ◽  
Temporal And Spatial

Although confronting cistemae (CC) have been observed in a variety of tumor cells and normal fetal rat, mouse, and human epithelial tissues, little is known about their origin or role in mitotic cells. While several investigators have suggested that CC arise from nuclear envelope (NE) folding back on itself during prophase, others have suggested that CC arise when fragments of NE pair with endoplasmic reticulum. An electron microscopic investigation of 0.25 um thick serial sections was undertaken to examine the origin of CC in HeLa cells.

Electron Microscopic investigation of crooke’s change in the pituitaries of patients with hypercorticism

1989 ◽  
Vol 47 ◽  
pp. 848-849
Author(s):  
E. Horvath ◽  
K. Kovacs ◽  
L. Stefaneanu ◽  
N. Losinski
Keyword(s):  
Nucleolar Organizer ◽  
Microscopic Investigation ◽  
Electron Microscopic Investigation ◽  
Ectopic Acth Syndrome ◽  
Nucleolar Organizer Regions ◽  
Electron Microscopic ◽  
Human Pituitary ◽  
Ectopic Acth ◽  
Crooke’S Hyalinization

Human pituitary corticotropins have unique morphologic markers: bundles of type-1 filaments, measuring approximately 70 A in width and representing cytokeratin. The extreme ring-like accumulation of type-1 filaments, known as Crooke's hyalinization, signals functional suppression of the corticotropins and occurs in endogenous and exogenous glucocorticoid excess, caused by ACTH-secreting pituitary adenoma, glucocorticoid secreting adrenocortical tumor, ectopic ACTH-syndrome and administration of pharmacologic doses of glucocorticoids. Cells of autonomous corticotroph adenomas usually do not show Crooke's hyalin change. A minority of these tumors, however, retains sensitivity to the negative feed-back effect of elevated blood glucocorticoid levels and display typical Crooke’s change.In the present study pituitary corticotropins in various phases of Crooke's hyalinization were investigated in patients with glucocorticoid excess of various origin, applying histology, immunocytochemistry, count of argyrophilic nucleolar organizer regions (AgNOR), and transmission electron microscopy.

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