Structural Features of Ingots Made of Al-Cu-Li System Alloys Depending on its Chemical Composition

A review of the literature data on the structural features of TRIP / TWIP steels, their relationship with mechanical properties and the relationship of strength parameters under static and cyclic loading was carried out. It is shown that the level of mechanical properties of such steels is determined by the chemical composition and processing technology (thermal and thermomechanical processing, hot and cold pressure treatment), aimed at achieving a favorable phase composition. At the atomic level, the most important factor is stacking fault energy, the level of which will be decisive in the formation of austenite twins and / or the formation of strain martensite. By selecting the chemical composition, it is possible to set the stacking fault energy corresponding to the necessary mechanical characteristics. In the case of cyclic loads, an important role is played by the strain rate and the maximum load during testing. So at high loading rates and a load approaching the yield strength under tension, the intensity of the twinning processes and the formation of martensite increases. It is shown that one of the relevant ways to further increase of the structural and functional properties of TRIP and TWIP steels is the creation of composite materials on their basis. At present, surface modification and coating, especially by ion-vacuum methods, can be considered the most promising direction for the creation of such composites.

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Optimization of Magnetic Properties of Magnetic Microwires by Post-Processing

Processes ◽

10.3390/pr8081006 ◽

2020 ◽

Vol 8 (8) ◽

pp. 1006

Author(s):

Valentina Zhukova ◽

Paula Corte-Leon ◽

Lorena González-Legarreta ◽

Ahmed Talaat ◽

Juan Maria Blanco ◽

...

Keyword(s):

Magnetic Properties ◽

Chemical Composition ◽

Hysteresis Loops ◽

Structural Features ◽

Post Processing ◽

Soft Magnetic ◽

Magnetic Microwires ◽

Prepared State ◽

Induced Magnetic Anisotropy ◽

Selection Of

The influence of post-processing conditions on the magnetic properties of amorphous and nanocrystalline microwires has been thoroughly analyzed, paying attention to the influence of magnetoelastic, induced and magnetocrystalline anisotropies on the hysteresis loops of Fe-, Ni-, and Co-rich microwires. We showed that magnetic properties of glass-coated microwires can be tuned by the selection of appropriate chemical composition and geometry in as-prepared state or further considerably modified by appropriate post-processing, which consists of either annealing or glass-coated removal. Furthermore, stress-annealing or Joule heating can further effectively modify the magnetic properties of amorphous magnetic microwires owing to induced magnetic anisotropy. Devitrification of microwires can be useful for either magnetic softening or magnetic hardening of the microwires. Depending on the chemical composition of the metallic nucleus and on structural features (grain size, precipitating phases), nanocrystalline microwires can exhibit either soft magnetic properties or semi-hard magnetic properties. We demonstrated that the microwires with coercivities from 1 A/m to 40 kA/m can be prepared.

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Structural features underlying recognition and translocation of extracellular polysaccharides

Interface Focus ◽

10.1098/rsfs.2018.0060 ◽

2019 ◽

Vol 9 (2) ◽

pp. 20180060 ◽

Cited By ~ 6

Author(s):

Jochen Zimmer

Keyword(s):

Energy Source ◽

Chemical Composition ◽

Cell Surface ◽

Cell Attachment ◽

Structural Features ◽

Living Systems ◽

Extracellular Polysaccharides ◽

Transport Mechanisms ◽

Complex Carbohydrates ◽

Insoluble Polymers

Essentially all living systems produce complex carbohydrates as an energy source, structural component, protective coat or adhesive for cell attachment. Many polysaccharides are displayed on the cell surface or are threaded through proteinaceous tunnels for degradation. Dictated by their chemical composition and mode of polymerization, the physical properties of complex carbohydrates differ substantially, from amphipathic water-insoluble polymers to highly hydrated hydrogel-forming macromolecules. Accordingly, diverse recognition and translocation mechanisms evolved to transport polysaccharides to their final destinations. This review will summarize and compare diverse polysaccharide transport mechanisms implicated in the biosynthesis and degradation of cell surface polymers in pro- and eukaryotes.

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Lake water and talik groundwater interaction in continuous permafrost, Central Yakutia

E3S Web of Conferences ◽

10.1051/e3sconf/20199807024 ◽

2019 ◽

Vol 98 ◽

pp. 07024

Author(s):

Nadezhda Pavlova ◽

Liudmila Lebedeva ◽

Vladimir Efremov

Keyword(s):

Chemical Composition ◽

Air Temperature ◽

Lake Water ◽

Structural Features ◽

Downward Trend ◽

Hydrological Data ◽

Hydrochemical Data ◽

Continuous Permafrost ◽

Solids Content ◽

Winter Air Temperature

Structural features of a lake talik associated with eolian relief are discussed. Analysis of hydrochemical and hydrological data for 2010-2017 showed that talik groundwater feeds lake and maintains perennial outflow from the lake. Variations in the chemical composition of the lake and outflowing creek are characterized on an annual and interannual basis. Seasonal comparison of hydrochemical data indicates a downward trend in dissolved-solids content of the lake water over the last six years, suggesting an increasing contribution of suprapermafrost groundwater to the lake and lake talik. Probable reason of enhanced suprapermafrost flow is increase of its duration due to observed rise of winter air temperature.

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Chemical Composition and Structural Features of the Macromolecular Components of PlantationAcacia mangiumWood

Journal of Agricultural and Food Chemistry ◽

10.1021/jf058081b ◽

2005 ◽

Vol 53 (20) ◽

pp. 7856-7862 ◽

Cited By ~ 31

Author(s):

Paula C. Pinto ◽

Dmitry V. Evtuguin ◽

Carlos Pascoal Neto

Keyword(s):

Chemical Composition ◽

Structural Features

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A Study of the Pore Surface State of Porous TiNi-based Materials Obtained by SHS at Various Ignition Temperatures

KnE Materials Science ◽

10.18502/kms.v2i1.777 ◽

2017 ◽

Vol 2 (1) ◽

pp. 25

Author(s):

S.G. Anikeev ◽

V.N. Khodorenko ◽

M.R. Mukhamedov ◽

V.E. Gunther

Keyword(s):

Surface Layer ◽

Chemical Composition ◽

Porous Material ◽

Variable Thickness ◽

Secondary Phase ◽

Structural Features ◽

Alloy Formation ◽

Pore Surface ◽

P 75 ◽

Phase And Chemical Composition

Structural features of porous TiNi-based materials obtained by SHS at temperatures of synthesis beginning of400 Cand600 Chave been investigated. It is found that finely porous material with a porosity P=75 % was obtained at the temperature of400 C. A surface of pore walls contains a dendritic relief, oxycarbidenitride layer and a multitude of secondary phase particles. Phase and chemical composition of the material is non-uniform. SHS material obtained at the synthesis beginning temperature of600 °Cis characterized as a coarse-porosity one P=65 %. Nano- and micropores are practically absent. The oxycarbidenitride surface layer with a variable thickness is substantially free of secondary inclusions due to the more complete processes of alloy formation. This layer has an own substructure based on carbonitride and oxynitride layers.

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CATIONIC CONDUCTIVITY IN MIXED POLYFERRITES

IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA ◽

10.6060/tcct.20165901.5103 ◽

2018 ◽

Vol 59 (1) ◽

pp. 23 ◽

Cited By ~ 3

Author(s):

L.G. Anikanova ◽

N.V. Dvoretskii ◽

Z.G. Malysheva

Keyword(s):

Chemical Composition ◽

Alkali Metal ◽

Metal Ion ◽

Alkali Metals ◽

Structural Features ◽

Alkali Metal Ion ◽

Mixed Alkali ◽

Unit Space ◽

Cation Radius

The effect of chemical composition on the cationic conductivity of mixed alkali metals β"-polyferrites was established. Cationic conductivity is determined by the mobility of alkali metal ion in inter-unit space which in turn depends on the ratio of cation radius and width of inter-unit space. The conductivity increases with z, and at the same z in the range of 0.28 – 0.4 becomes constant (z in the formula Me2-zAdzFe11O17, where Me - the basic alkali metal, Ad - introduced alkali metal ion, which has the larger radius (Cs, Rb)) for all samples. This is due to the structural features of polyferrites.

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Chemical Composition and Biological Activity of Paris quadrifolia L.

Zeitschrift für Naturforschung C ◽

10.1515/znc-2012-11-1206 ◽

2012 ◽

Vol 67 (11-12) ◽

pp. 565-570 ◽

Cited By ~ 1

Author(s):

Kristina Jenett-Siems ◽

Nadin Krause ◽

Karsten Siems ◽

Sven Jakupovic ◽

Gerd Wallukat ◽

...

Keyword(s):

Biological Activity ◽

Chemical Composition ◽

Structural Features ◽

Model System ◽

Cardiac Cells ◽

Steroidal Saponin ◽

Cellular Model ◽

Potential Influence ◽

Plant Compounds

A study of the components of Paris quadrifolia was undertaken to identify compounds with potential influence on cardiac cells, since previous reports suggested a cardiotoxic risk of this plant. Compounds isolated and identified included one new steroidal saponin, (23S,24S)- spirosta-5,25(27)-diene-1β,3β,21,23,24-pentol-1-O-β-D-apiofuranosyl-(1→3)-α-L-rhamnopyranosyl-( 1→2)-[β-D-xylopyranosyl-(1→3)]-β-D-glucopyranoside 21- O- β- D- apiofuranoside 24-O-β-D-fucopyranoside (1), demonstrating quite unusual structural features, as well as the known compounds 26-O-β-D-glucopyranosyl-(25R)-5-en-furost-3β,17α,22α,26-tetraol- 3- O- α- L- rhamnopyranosyl-(1→4)-α-L-rhamnopyranosyl-(1→4)-[α-L-rhamnopyranosyl - -(1→2)]- β- D- glucopyranoside (2), pennogenin 3-O-α-L-rhamnopyranosyl-(1→4)-α-L-rhamno pyranosyl- (1→4)-[α-L-rhamnopyranosyl-(1→ 2)]-β -D- glucopyranoside (3), 7- O- β- D-glucopyranosyl- kaempferol-3- O- β- D-glucopyranosyl-(1→2)-β- D-galactopyranoside (4), kaem pferol- 3-O-β-D-glucopyranosyl-(1→2)-β-D-galactopyranoside (5), 5-hydroxyecdysterone (6), and 20-hydroxyecdysone (7). The pennogenin derivative 3 showed strong cardiotoxic effects in an in vitro cellular model system, whereas the respective furostanol derivative 2 was inactive.

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Analysis of Structural Features of Humic Acids Fractions after Mechanochemical Modification

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1085.3 ◽

2015 ◽

Vol 1085 ◽

pp. 3-6 ◽

Cited By ~ 4

Author(s):

Malika P. Mirzobekzoda ◽

Elizaveta V. Maltseva ◽

Natalya S. Shekhovtsova

Keyword(s):

Chemical Composition ◽

Ir Spectroscopy ◽

Humic Acids ◽

Fulvic Acids ◽

Structural Features ◽

Acid Base ◽

Structural Composition ◽

Mechanochemical Modification ◽

The Impact ◽

First Time

Humic substances are the major components of soil, peat and brown coal. They can be fractionating into fulvic acids (FA), brown humic acids (BHA) and gray humic acids (GHA). In this work we investigated the influence of mechanochemical modifications on structural composition of HAs main fractions using the methods of IR and 1H MRS spectroscopy. The IR spectroscopy results has shown that HA has different chemical composition in comparison with GHA and BHA. Potentiometric titration showed that mechanoactivation (MA) with thiourea increases the amount of oxygen-containing groups up to 2.5. For the first time we studied the impact of modifying agent of thiourea on the structural composition and acid-base properties of HAs major fractions - GHA and BHA during the mechanoactivation process.

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