Influence of Fe doping on the Yb valence state and the magnetic structures in HoFe6Sn6-type YbMn6−yFeySn6 alloys (y ≤ 1.00)

Contrast of Filament Bright Rims

International Astronomical Union Colloquium ◽

10.1017/s0252921100025628 ◽

1994 ◽

Vol 144 ◽

pp. 365-367

Author(s):

E. V. Kononovich ◽

O. B. Smirnova ◽

P. Heinzel ◽

P. Kotrč

Keyword(s):

High Altitude ◽

Line Profile ◽

Line Center ◽

Magnetic Structures ◽

The Mean

AbstractThe Hα filtergrams obtained at Tjan-Shan High Altitude Observatory near Alma-Ata (Moscow University Station) were measured in order to specify the bright rims contrast at different points along the line profile (0.0; ± 0.25; ± 0.5; ± 0.75 and ± 1.0 Å). The mean contrast value in the line center is about 25 percent. The bright rims interpretation as the bases of magnetic structures supporting the filaments is suggested.

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Dislocations, Ordering and Antiferromagnetic Domains in MnO

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069600 ◽

1970 ◽

Vol 28 ◽

pp. 522-523

Author(s):

D. J. Barber ◽

R. G. Evans

Keyword(s):

Electron Diffraction ◽

Single Crystal ◽

Optical Microscopy ◽

Defect Chemistry ◽

Magnetic Structures ◽

Optically Transparent ◽

Magnetic Features ◽

Antiferromagnetic Domains

Manganese (II) oxide, MnO, in common with CoO, NiO and FeO, possesses the NaCl structure and shows antiferromagnetism below its Neel point, Tn∼ 122 K. However, the defect chemistry of the four oxides is different and the magnetic structures are not identical. The non-stoichiometry in MnO2 small (∼2%) and below the Tn the spins lie in (111) planes. Previous work reported observations of magnetic features in CoO and NiO. The aim of our work was to find explanations for certain resonance results on antiferromagnetic MnO.Foils of single crystal MnO were prepared from shaped discs by dissolution in a mixture of HCl and HNO3. Optical microscopy revealed that the etch-pitted foils contained cruciform-shaped precipitates, often thick and proud of the surface but red-colored when optically transparent (MnO is green). Electron diffraction and probe microanalysis indicated that the precipitates were Mn2O3, in contrast with recent findings of Co3O4 in CoO.

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Valence state analysis of elements by EPMA and its application

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100134752 ◽

1990 ◽

Vol 48 (2) ◽

pp. 230-231

Author(s):

Chen Liqing ◽

Liu Zuqin ◽

Zhang Wei

Keyword(s):

Valence State ◽

Line Intensities ◽

Valence States ◽

Valence Electrons ◽

Fe And Mn ◽

Intensity Ratios ◽

State Analysis

Valence state analyses of Fe and Mn in oxides by EPMA have been reported in literature. In this paper, the effects of valence state on intensity ratios ILα/IKα and ILα/ILβ of Cu, Ni, Co, Fe, Mn, Cr and their oxides, and on intensity ratios ILβ2/ILα1 and ILγ1/ILα1 of Mo, Nb, Zr and their oxides were studied. It was observed that intensity ratios change with valence states in accordance with some regularities, and these effects could be utilized for analyzing the valence states of catalysts.Valence state analysis of elements by EPMA is based on the fact that changes in the states of valence electrons in the outer shells of an atom cause corresponding changes in line intensities. The M electrons of Cu, Ni, Co, Fe, Mn, Cr and the N electrons of Mo, Nb, Zr are valence electrons. Line Kα1,2 and six lines of L are produced from the transitions of K-L2,3 and L-M or L-N respectively.

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Theory for the mixed-valence state

Le Journal de Physique Colloques ◽

10.1051/jphyscol:19795133 ◽

1979 ◽

Vol 40 (C5) ◽

pp. C5-374-C5-374 ◽

Cited By ~ 1

Author(s):

C. M. Varma

Keyword(s):

Valence State ◽

Mixed Valence ◽

Mixed Valence State

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MIXED VALENCE STATE OF Sm ON THE SURFACE OF AMORPHOUS La80-xSmxAu20 ALLOYS

Le Journal de Physique Colloques ◽

10.1051/jphyscol:19808198 ◽

1980 ◽

Vol 41 (C8) ◽

pp. C8-799-C8-802 ◽

Cited By ~ 4

Author(s):

G. Krill ◽

A. Amamou ◽

A. Berrada ◽

J. Durand ◽

N. Hassanain

Keyword(s):

Valence State ◽

Mixed Valence ◽

Mixed Valence State

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Tc-99m Labeled Complexes of Aldehydes and Glutamate as Cholescintigraphic Agents

Nuklearmedizin ◽

10.1055/s-0038-1624914 ◽

1975 ◽

Vol 14 (04) ◽

pp. 330-338

Author(s):

L. G. Colombetti ◽

J. S. Arnold ◽

W. E. Barnes

Keyword(s):

Nuclear Medicine ◽

Gall Bladder ◽

Rose Bengal ◽

Valence State ◽

Monosodium Glutamate ◽

Kinetic Studies ◽

Scintillation Camera ◽

Blood Clearance ◽

Lower Valence ◽

Wire Basket

SummaryTc-99m pyridoxylidene glutamate has proven to be an excellent biliary scanning agent, far superior in many respect to the commonly used 1-131 rose bengal. The preparation of the compound as previously reported by Baker et al is too time consuming and requires the use of an autoclave which is not available in most nuclear medicine departments. In our facility, we have been preparing similar compounds using several aldehydes and monosodium glutamate to make labeled complexes having the same pharmacological characteristics. The mixture of monosodium glutamate, aldehyde, and Tc-99m pertechnetate is made slightly alkaline, purged with helium, and placed in a sealed vial. The vial, which is protected by a wire basket, is then heated in a laboratory oven at 130° C for a period of 15 to 20 minutes. During this time, the technetium is reduced to a lower valence state and bound to the complex formed. Chromatographic data show that these compounds are chemically similar to that previously reported. The compounds prepared concentrate in the gall bladder of the rabbit in less than 10 minutes. Kinetic studies have been performed on dogs with a scintillation camera and small digital computer to measure rates of blood clearance, liver and gall bladder uptake, and excretion into the intestine. The aldehyde — glutamate complex promises to be a useful scanning agent for the diagnosis of biliary and hepatocellular diseases.

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