Relationship between Erosion and Mechanical Characteristics of Fine-Grained Hard Alloy WC – 16% Co Obtained by Solid-Phase and Liquid-Phase Consolidation. Part 1. Erosion Resistance

The liquid-phase sintering at 1860‒2100 °C was used to prepare the silicon-carbide materials with the 5‒10 weigh percent of oxide additions. The SiC material with the 20 weigh percent of three-component MgO‒Y2O3‒Al2O3system addition showed the ultimate physical and mechanical properties. The mechanical characteristics of the liquidphase sintered materials with the 15 weigh percent of the three-component oxides addition exceed those of both the reactive-sintered and the solid-phase sintered materials and approach to those of the hot-pressed materials.Ill. 5. Ref. 31. Tab. 2.

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Microstructural and Mechanical Characteristics of in Situ Synthesized Chromium-Nickel-Graphite Composites

Materials Science Forum ◽

10.4028/www.scientific.net/msf.534-536.1209 ◽

2007 ◽

Vol 534-536 ◽

pp. 1209-1212 ◽

Cited By ~ 5

Author(s):

Jüri Pirso ◽

Mart Viljus ◽

Sergej Letunovits ◽

Kristjan Juhani

Keyword(s):

Mechanical Characteristics ◽

Erosion Resistance ◽

Rupture Strength ◽

High Energy ◽

Binder Phase ◽

Reactive Sintering ◽

In Situ Composite ◽

Fine Grained ◽

Graphite Composites

Cr-C-Ni composites were synthesized in situ from elemental powders of Cr, Ni and C by high energy milling followed by reactive sintering. The milled powders with the grain size in nano-scale were pressed to compacts and sintered. During the thermal treatment that was performed after the pressing the chromium carbide was formed first and then the Cr3C2-Ni cermets were sintered in one cycle. The interface between the binder phase and the carbide grains of the in situ composite has a good bonding strength as it is not contaminated with oxidation films or other detrimental surface reactions. The microstructure of such cermets is fine-grained and more homogeneous than that of cermets produced by conventional method. As a result the cermets have higher hardness, transverse rupture strength and 1.2-2 times higher wear and erosion resistance.

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Identification of hepatitis a virus in cell cultures by solid phase immune electron microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100142815 ◽

1986 ◽

Vol 44 ◽

pp. 238-239

Author(s):

C.D. Humphrey ◽

T.L. Cromeans ◽

E.H. Cook ◽

D.W. Bradley

Keyword(s):

Electron Microscopy ◽

Liquid Phase ◽

Cell Cultures ◽

Rapid Detection ◽

Hepatitis A ◽

Hepatitis A Virus ◽

Solid Phase ◽

Immune Electron Microscopy ◽

Detection And Identification

There is a variety of methods available for the rapid detection and identification of viruses by electron microscopy as described in several reviews. The predominant techniques are classified as direct electron microscopy (DEM), immune electron microscopy (IEM), liquid phase immune electron microscopy (LPIEM) and solid phase immune electron microscopy (SPIEM). Each technique has inherent strengths and weaknesses. However, in recent years, the most progress for identifying viruses has been realized by the utilization of SPIEM.

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SYNTHESIS OF HYDROGEN IN ACOUSTOPLASMA DISCHARGE IN A LIQUID-PHASE STREAM

Alternative Energy and Ecology (ISJAEE) ◽

10.15518/isjaee.2019.01-03.042-048 ◽

2019 ◽

pp. 42-48 ◽

Cited By ~ 2

Author(s):

N. A. Bulychev

Keyword(s):

Liquid Phase ◽

Organic Compounds ◽

Electrode Materials ◽

Solid Phase ◽

Plasma Discharge ◽

Raw Material ◽

Two Phase ◽

Reduced Pressure ◽

External Power Source ◽

Phase Medium

In this paper, the plasma discharge in a high-pressure fluid stream in order to produce gaseous hydrogen was studied. Methods and equipment have been developed for the excitation of a plasma discharge in a stream of liquid medium. The fluid flow under excessive pressure is directed to a hydrodynamic emitter located at the reactor inlet where a supersonic two-phase vapor-liquid flow under reduced pressure is formed in the liquid due to the pressure drop and decrease in the flow enthalpy. Electrodes are located in the reactor where an electric field is created using an external power source (the strength of the field exceeds the breakdown threshold of this two-phase medium) leading to theinitiation of a low-temperature glow quasi-stationary plasma discharge.A theoretical estimation of the parameters of this type of discharge has been carried out. It is shown that the lowtemperature plasma initiated under the flow conditions of a liquid-phase medium in the discharge gap between the electrodes can effectively decompose the hydrogen-containing molecules of organic compounds in a liquid with the formation of gaseous products where the content of hydrogen is more than 90%. In the process simulation, theoretical calculations of the voltage and discharge current were also made which are in good agreement with the experimental data. The reaction unit used in the experiments was of a volume of 50 ml and reaction capacity appeared to be about 1.5 liters of hydrogen per minute when using a mixture of oxygen-containing organic compounds as a raw material. During their decomposition in plasma, solid-phase products are also formed in insignificant amounts: carbon nanoparticles and oxide nanoparticles of discharge electrode materials.

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Prion-Like Proteins in Phase Separation and Their Link to Disease

Biomolecules ◽

10.3390/biom11071014 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1014

Author(s):

Macy L. Sprunger ◽

Meredith E. Jackrel

Keyword(s):

Protein Folding ◽

Phase Transitions ◽

Phase Separation ◽

Liquid Phase ◽

Protein Misfolding ◽

Solid Phase ◽

Liquid Phase Separation ◽

Therapeutic Approaches ◽

Important Physiological Process ◽

Liquid Liquid Phase Separation

Aberrant protein folding underpins many neurodegenerative diseases as well as certain myopathies and cancers. Protein misfolding can be driven by the presence of distinctive prion and prion-like regions within certain proteins. These prion and prion-like regions have also been found to drive liquid-liquid phase separation. Liquid-liquid phase separation is thought to be an important physiological process, but one that is prone to malfunction. Thus, aberrant liquid-to-solid phase transitions may drive protein aggregation and fibrillization, which could give rise to pathological inclusions. Here, we review prions and prion-like proteins, their roles in phase separation and disease, as well as potential therapeutic approaches to counter aberrant phase transitions.

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Application of the Composite Hardness Models in the Analysis of Mechanical Characteristics of Electrolytically Deposited Copper Coatings: The Effect of the Type of Substrate

Metals ◽

10.3390/met11010111 ◽

2021 ◽

Vol 11 (1) ◽

pp. 111

Author(s):

Ivana O. Mladenović ◽

Nebojša D. Nikolić ◽

Jelena S. Lamovec ◽

Dana Vasiljević-Radović ◽

Vesna Radojević

Keyword(s):

Mechanical Characteristics ◽

Dislocation Creep ◽

Average Current Density ◽

Fine Grained ◽

Copper Coatings ◽

Electrochemically Deposited ◽

Composite Models ◽

Average Current ◽

Composite Hardness ◽

Coating Hardness

The mechanical characteristics of electrochemically deposited copper coatings have been examined by application of two hardness composite models: the Chicot-Lesage (C-L) and the Cheng-Gao (C-G) models. The 10, 20, 40 and 60 µm thick fine-grained Cu coatings were electrodeposited on the brass by the regime of pulsating current (PC) at an average current density of 50 mA cm−2, and were characterized by scanning electron (SEM), atomic force (AFM) and optical (OM) microscopes. By application of the C-L model we determined a limiting relative indentation depth (RID) value that separates the area of the coating hardness from that with a strong effect of the substrate on the measured composite hardness. The coating hardness values in the 0.9418–1.1399 GPa range, obtained by the C-G model, confirmed the assumption that the Cu coatings on the brass belongs to the “soft film on hard substrate” composite hardness system. The obtained stress exponents in the 4.35–7.69 range at an applied load of 0.49 N indicated that the dominant creep mechanism is the dislocation creep and the dislocation climb. The obtained mechanical characteristics were compared with those recently obtained on the Si(111) substrate, and the effects of substrate characteristics such as hardness and roughness on the mechanical characteristics of the electrodeposited Cu coatings were discussed and explained.

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A Study of the Impact of Graphite on the Kinetics of SPS in Nano- and Submicron WC-10%Co Powder Compositions

Ceramics ◽

10.3390/ceramics4020025 ◽

2021 ◽

Vol 4 (2) ◽

pp. 331-363

Author(s):

Eugeniy Lantcev ◽

Aleksey Nokhrin ◽

Nataliya Malekhonova ◽

Maksim Boldin ◽

Vladimir Chuvil'deev ◽

...

Keyword(s):

Activation Energy ◽

Solid Phase ◽

Continuous Heating ◽

Diffusion Creep ◽

Hard Alloys ◽

Fine Grained ◽

Plasma Sintering ◽

Spark Plasma ◽

The Impact ◽

Kinetics Of

This study investigates the impact of carbon on the kinetics of the spark plasma sintering (SPS) of nano- and submicron powders WC-10wt.%Co. Carbon, in the form of graphite, was introduced into powders by mixing. The activation energy of solid-phase sintering was determined for the conditions of isothermal and continuous heating. It has been demonstrated that increasing the carbon content leads to a decrease in the fraction of η-phase particles and a shift of the shrinkage curve towards lower heating temperatures. It has been established that increasing the graphite content in nano- and submicron powders has no significant effect on the SPS activation energy for “mid-range” heating temperatures, QS(I). The value of QS(I) is close to the activation energy of grain-boundary diffusion in cobalt. It has been demonstrated that increasing the content of graphite leads to a significant decrease in the SPS activation energy, QS(II), for “higher-range” heating temperatures due to lower concentration of tungsten atoms in cobalt-based γ-phase. It has been established that the sintering kinetics of fine-grained WC-Co hard alloys is limited by the intensity of diffusion creep of cobalt (Coble creep).

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Effect of maturity of Napier grass (Pennisetum purpureum) hay on intake, digestibility, and rumen dynamics when given to zebu bulls

Proceedings of the British Society of Animal Science ◽

10.1017/s1752756200001459 ◽

2000 ◽

Vol 2000 ◽

pp. 144-144

Author(s):

A.J. Ayala-Burgos ◽

F.D.DeB. Hovell ◽

R.M. Godoy ◽

Hamana S. Saidén ◽

R. López ◽

...

Keyword(s):

Liquid Phase ◽

Solid Phase ◽

Napier Grass ◽

Pennisetum Purpureum ◽

Ad Libitum ◽

The Tropics ◽

Kinetics Of

Cattle in the tropics mostly depend on pastures. During dry periods the forage available is usually mature, constraining both intake and digestion. These constraints need to be understood, for intake and digestibility define productivity. Intake depends on the rumen space made available by fermentation and outflow. Markers such as PEG (liquid phase), and chromium mordanted fibre (solid phase) can be used to measure rumen volume and outflow, but have limitations. The objective of this experiment was to measure intake, digestibility, and rumen kinetics of cattle fed ad libitum forages with very different degradation characteristics, and also to compare rumen volumes measured with markers with those obtained by manual emptying.

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Effect of microbial isolates on microbial yield estimation in RUSITEC system

BSAP Occasional Publication ◽

10.1017/s0263967x0003295x ◽

1998 ◽

Vol 22 ◽

pp. 306-308

Author(s):

M. D. Carro ◽

E. L. Miller

Keyword(s):

Protein Synthesis ◽

Liquid Phase ◽

Solid Phase ◽

Liquid Fraction ◽

Microbial Protein ◽

Microbial Protein Synthesis ◽

Continuous Culture System ◽

The One

The estimation of rumen microbial protein synthesis is one of the main points in the nitrogen (N)-rationing systems for ruminants, as microbial protein provides proportionately 0.4 to 0.9 of amino acids entering the small intestine in ruminants receiving conventional diets (Russell et al., 1992). Methods of estimating microbial protein synthesis rely on marker techniques in which a particular microbial constituent is related to the microbial N content. Marker : N values have generally been established in mixed bacteria isolated from the liquid fraction of rumen digesta and it has been assumed that the same relationship holds in the total population leaving the rumen (Merry and McAllan, 1983). However, several studies have demonstrated differences in composition between solid-associated (SAB) and fluid-associated bacteria in vivo (Legay-Carmier and Bauchart, 1989) and in vitro (Molina Alcaide et al, 1996), as well in marker : N values (Pérez et al., 1996). This problem could be more pronounced in the in vitro semi-continuous culture system RUSITEC, in which there are three well defined components (a free liquid phase, a liquid phase associated with the solid phase and a solid phase), each one having associated microbial populations.The objective of this experiment was to investigate the effect of using different bacterial isolates (BI) on the estimation of microbial production of four different diets in RUSITEC (Czerkawski and Breckenridge, 1977), using (15NH4)2 SO4 as microbial marker, and to assess what effects any differences would have on the comparison of microbial protein synthesis between diets.This study was conducted in conjunction with an in vitro experiment described by Carro and Miller (1997). Two 14-day incubation trials were carried out with the rumen simulation technique RUSITEC (Czerkawski and Breckenridge, 1977). The general incubation procedure was the one described by Czerkawski and Breckenridge (1977) and more details about the procedures of this experiment are given elsewhere (Carro and Miller, 1997).

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