Solidification Reaction Sequence of Co-Rich Nb-Al-Co Alloys

Fe-Cr-Co alloys have great technological potential to replace Alnico alloys as hard magnets. The relationship between the microstructures and the magnetic properties has been recently established for some of these alloys. The magnetic hardening has been attributed to the decomposition of the high temperature stable phase (α) into an elongated Fe-rich ferromagnetic phase (α1) and a weakly magnetic or non-magnetic Cr-rich phase (α2). The relationships between magnetic domains and domain walls and these different phases are yet to be understood. The TEM has been used to ascertain the mechanism of magnetic hardening for the first time in these alloys. The present paper describes the magnetic domain structure and the magnetization reversal processes in some of these multiphase materials. Microstructures to change properties resulting from, (i) isothermal aging, (ii) thermomagnetic treatment (TMT) and (iii) TMT + stepaging have been chosen for this investigation. The Jem-7A and Philips EM-301 transmission electron microscopes operating at 100 kV have been used for the Lorentz microscopy study of the magnetic domains and their interactions with the finely dispersed precipitate phases.

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TEM INVESTIGATIONS OF WC-Co ALLOYS AFTER CREEP EXPERIMENTS

Le Journal de Physique Colloques ◽

10.1051/jphyscol:19861105 ◽

1986 ◽

Vol 47 (C1) ◽

pp. C1-685-C1-689 ◽

Cited By ~ 1

Author(s):

S. LAY ◽

F. OSTERSTOCK ◽

J. VICENS

Keyword(s):

Co Alloys

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Leaching Studies of Cement-Glass Package Containing Sodium Borate

MRS Proceedings ◽

10.1557/proc-84-393 ◽

1986 ◽

Vol 84 ◽

Cited By ~ 3

Author(s):

Masahiro Okamoto ◽

Koichi Chino ◽

Tsutomu Baba ◽

Tatsuo Izumida ◽

Fumio Kawamura ◽

...

Keyword(s):

Sodium Silicate ◽

Liquid Waste ◽

Sodium Borate ◽

Pressurized Water Reactor ◽

X Ray Diffraction ◽

Adsorption Ability ◽

Pressurized Water ◽

X Ray ◽

Solidification Reaction ◽

Main Components

AbstractA new solidification technique using cement-glass, which is a mixture of sodium silicate, cement, additives, and initiator of the solidification reaction, was developed for sodium borate liquid waste generated from pressurized water reactor (PWR) plants. The cement-glass could solidify eight times as much sodium borate as cement could, because the solidifying reaction of the cement-glass is not hindered by borate ions.The reaction mechanism of sodium silicate and phosphoric silicate (initiator), the main components of cement-glass, was studied through X-ray diffraction and compressive strength measurements. It was found that three- dimensionally bonded silicon dioxide was produced by polymerization of the two silicates. The leaching ratio of cesium from the cement-glass package was one-tenth that of the cement one. This low value was attributed to a high cesium adsorption ability of the cement-glass and it could be theoretically predicted accordingly.

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An Efficient Imine Photocyclization as an Alternative to the Pictet-Spengler Reaction for the Synthesis of AzaBenzannulated Perylenediimide Dyes

10.26434/chemrxiv.11878086.v1 ◽

2020 ◽

Cited By ~ 2

Author(s):

Antoine Goujon ◽

Lou Rocard ◽

Thomas Cauchy ◽

Piétrick Hudhomme

Keyword(s):

Solar Cells ◽

Visible Light ◽

Organic Solar Cells ◽

Reaction Sequence ◽

Large Scope ◽

High Yields

AzaBenzannulated PDI (AzaBPDI) dyes were synthesized in high yields via a new reaction sequence involving an imine condensation followed by visible light-induced photocyclization. The large scope and efficiency of this alternative to the Pictet-Spengler reaction is demonstrated, and allows the easy preparation of dimeric AzaBPDI as potential non-fullerene acceptors for organic solar cells.

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Preparation of (20E)-21-Ethoxycarbonyl-14β,17α-pregna-5,20-dien-3β-yl Hydrogen Butanedioate

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19950715 ◽

1995 ◽

Vol 60 (4) ◽

pp. 715-718 ◽

Cited By ~ 1

Author(s):

Vladimír Pouzar ◽

Ivan Černý

Keyword(s):

Title Compound ◽

Nmr Spectra ◽

Total Yield ◽

Reaction Sequence ◽

Pregnane Series ◽

H Nmr

The title compound X was prepared according to the recently published procedure for preparation of analogous derivatives in the 5β-pregnane series, using the reaction sequence I -> II -> III -> IV -> V -> VI -> VII -> VII -> IX -> X (total yield 18%). The configuration at ring D centers (14β,17α) follows from the structure of the starting ketone I and was also checked by comparing diol IV with the sample prepared by an independent route. The epimeric purity at C-17 was carefully monitored during the whole synthesis by 1H NMR spectra (singlet of 18-H3).

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Pentose Phosphate Pathway Reactions in Photosynthesizing Cells

Cells ◽

10.3390/cells10061547 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1547

Author(s):

Thomas D. Sharkey

Keyword(s):

Pentose Phosphate Pathway ◽

Strong Association ◽

Pentose Phosphate ◽

Critical Component ◽

Reaction Sequence ◽

Response To Stress ◽

Labeling Pattern

The pentose phosphate pathway (PPP) is divided into an oxidative branch that makes pentose phosphates and a non-oxidative branch that consumes pentose phosphates, though the non-oxidative branch is considered reversible. A modified version of the non-oxidative branch is a critical component of the Calvin–Benson cycle that converts CO2 into sugar. The reaction sequence in the Calvin–Benson cycle is from triose phosphates to pentose phosphates, the opposite of the typical direction of the non-oxidative PPP. The photosynthetic direction is favored by replacing the transaldolase step of the normal non-oxidative PPP with a second aldolase reaction plus sedoheptulose-1,7-bisphosphatase. This can be considered an anabolic version of the non-oxidative PPP and is found in a few situations other than photosynthesis. In addition to the strong association of the non-oxidative PPP with photosynthesis metabolism, there is recent evidence that the oxidative PPP reactions are also important in photosynthesizing cells. These reactions can form a shunt around the non-oxidative PPP section of the Calvin–Benson cycle, consuming three ATP per glucose 6-phosphate consumed. A constitutive operation of this shunt occurs in the cytosol and gives rise to an unusual labeling pattern of photosynthetic metabolites while an inducible shunt in the stroma may occur in response to stress.

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PRODUCTION OF ULTRASTRUCTURAL MEMBRANE LESIONS BY THE FIFTH COMPONENT OF COMPLEMENT

Journal of Experimental Medicine ◽

10.1084/jem.133.1.53 ◽

1971 ◽

Vol 133 (1) ◽

pp. 53-62 ◽

Cited By ~ 26

Author(s):

Margaret J. Polley ◽

Hans J. Müller-Eberhard ◽

Joseph D. Feldman

Keyword(s):

Structural Change ◽

Cell Membrane ◽

Quantitative Relationship ◽

Intermediate Complex ◽

Reaction Sequence ◽

Immune Hemolysis ◽

Physical Presence ◽

Reverse Situation

A direct quantitative relationship has been demonstrated between the number of cell bound C4,2 complexes or C5 molecules and the number of ultrastructural lesions visualized on the cell membrane subsequent to immune hemolysis. When bound C4,2 complexes exceeded bound C5 molecules, the number of ultrastructural lesions seen corresponded to the number of C5 molecules. However, in the reverse situation, with bound C5 molecules in excess of bound C4,2 complexes, the latter determined the number of lesions. During the complement-reaction sequence, the lesions first became visible in the nonlytic intermediate complex EAC1,4,2,3,5 and their number was unaffected when lysis was induced by C6–C9. Since the lesions were also demonstrable on the intermediate complex EC5,6,7, it is concluded that the protein C5 is responsible for their production. Once formed, the physical presence of the C5 molecule is no longer required for the manifestation of the lesions as indicated by persistence of lesions after removal of C5 protein by trypsin. The C5-dependent ultra-structural phenomenon has therefore been interpreted to represent a true structural change of the membrane which, however, is not accompanied by a permeability defect.

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