A new form of the high-temperature isopiestic technique and its application to mercury–bismuth, mercury–cadmium, mercury–gallium, mercury–indium and mercury–tin binary amalgams

1988 ◽  
Vol 84 (12) ◽  
pp. 4369 ◽  
Author(s):  
Zhi-Chang Wang ◽  
Xin-Hua Zhang ◽  
Yu-Zhi He ◽  
Yu-Hong Bao
Keyword(s):  
High Temperature ◽  
New Form ◽  
Isopiestic Technique

Monodisperse single nanodiamond particulates

2008 ◽  
Vol 80 (7) ◽  
pp. 1365-1379 ◽  
Author(s):  
Eiji Ōsawa
Keyword(s):  
High Temperature ◽  
Sol Gel ◽  
Turn Of The Century ◽  
Detonation Nanodiamond ◽  
Wet Milling ◽  
Bottom Up ◽  
High Temperature And Pressure ◽  
Primary Particles ◽  
New Form ◽  
Temperature And Pressure

Detonation nanodiamond (DN) was discovered in 1963, but for several reasons was known only among a small number of scientists until the turn of the century. The most serious cause was the fact that primary nanocarbon particles formed by the "bottom-up method" are in general covalently bound together under high-temperature and -pressure conditions to form large agglutinates, which were difficult to separate by conventional methods. DN was not an exception. A breakthrough led to the isolation of primary particles having the expected size of 4-5 nm by wet-milling with zirconia micro-beads. Thus, long-waited primary particles of DN finally became available in kg quantities in the form of colloidal sol, gel, and readily redispersible flakes. Progress in the development of a new form of the old material is presented.

Stagnation pressure effect on Prandtl Meyer function for air

2016 ◽  
Vol 231 (2) ◽  
pp. 326-337 ◽  
Author(s):  
Merouane Salhi ◽  
Toufik Zebbiche ◽  
Abderrahmane Mehalem
Keyword(s):  
High Temperature ◽  
Pressure Effect ◽  
Molecular Size ◽  
State Equation ◽  
Stagnation Pressure ◽  
Intermolecular Force ◽  
Perfect Gas ◽  
Real Gas ◽  
New Form ◽  
Made In

When the stagnation pressure of a perfect gas increases, the specific heat and their ratio do not remain constant anymore and start to vary with this pressure. The gas does not stay perfect. Its state equation change and it becomes for a real gas. In this case, the effects of molecular size and intermolecular attraction forces intervene to correct the state equation, the thermodynamic parameters and the value of Prandtl Meyer function. The aim of this work is developing a new form of Prandtl Meyer function based on those assumptions; and determining the effect of stagnation pressure on this function. With the assumptions that Berthelot’s state equation accounts for molecular size and intermolecular force effects, expressions are developed for analysing the supersonic flow for thermally and calorically imperfect gas lower than the dissociation molecules threshold. The supersonic parameters depend directly on the stagnation parameters of the combustion chamber. The application is for air. A computation of error was made in this case to give a limit of the perfect gas and the high temperature models compared to the real gas model.

Extensive dolomitic volcanism through the Limagne Basin, central France: a new form of carbonatite activity

2006 ◽  
Vol 70 (2) ◽  
pp. 231-236 ◽  
Author(s):  
K. Bailey ◽  
S. Kearns ◽  
J. Mergoil ◽  
J. Mergoil Daniel ◽  
B. Paterson
Keyword(s):  
High Temperature ◽  
Silicate Glass ◽  
Silicate Melt ◽  
Central Spain ◽  
Deep Mantle ◽  
First Case ◽  
New Findings ◽  
New Form ◽  
Active Research

AbstractRecognition of widespread carbonate volcanism in central Spain has led to another case in France, of similar age (23–0 Ma) but with entirely new features. More than 100 new carbonate volcanoes are indicated already, adding a wholly unexpected dimension to this form of activity. Eruptions form layers, mostly of glassy nephelinite fragments in a dolomitic matrix, but some layers are largely dolomite. Major new findings are phenocrysts of dolomite, magnesite and calcite in silicate glass, and spectacular dolomite-nephelinite melt immiscibility, neither recorded previously. Most volcanic carbonatites are Ca rich, and dolomite is rare. The Limagne dolomites share links with those in Spain and Zambia, with chromite a hallmark in all three. Limagne is exceptional in being the first case where dolomite has erupted with co-genetic silicate melt. Mantle debris and magnesite indicate a source within ∼ 100–150 km. Chromite in the dolomite globules, and in the enclosing silicate glass, is similar to that in high-temperature kimberlites, indicating immiscibility in the deep mantle. Recognition of two large, previously undetected provinces of carbonate volcanism in Europe, where there has been active research for >200 y, must lead to the inference that similar cases may await discovery on other continents.

scholarly journals On the viscosities of gaseous chlorine and bromine

1912 ◽  
Vol 86 (585) ◽  
pp. 162-168 ◽  
Keyword(s):  
Surface Tension ◽  
High Temperature ◽  
Pressure Difference ◽  
Constant Pressure ◽  
Capillary Tube ◽  
Deep Layer ◽  
Atmospheric Temperature ◽  
Higher Temperature ◽  
New Form

The Object of the Experiments about to be described was to determine the viscosities, at various temperature, of gaseous chlorine, bromine, and iodine, by comparison with air. The apparatus, however, proved unsuitable in several respects for working at higher temperature required. It has, nevertheless, yielded satisfactory results at the lower temperatures ; and the viscosity of chlorine at atmospheric temperature and at 100° C., and that of bromine at the latter temperature only, have been measured by means of it. These values are now published, pending the extension of the investigation on the lines indicated, with a new form of apparatus which promises to be entirely adequate for the purpose. The chief difficulty which presents itself in working with the halogen gases is the readiness with which they attack mercury. On this account, the method I Have previously used* for viscosity determinations was rendered unsuitable; but it has found possible to retain one of its most desirable features, viz., the mercury pellet, which serve the double purpose of creating a constant pressure difference, and of measuring the volume of gas emerging from capillary. In other respects the apparatus is quite different, the main object in its construction being to prevent contamination of the mercury. This has been sufficiently secured by causing the pellet to aspirate the gas through the capillary tube, with a deep layer of air acting as a kind of buffer between them. The failure of the method at high temperature was chiefly due to the mercury pellet becoming unstable, owing to the diminution of surface tension.

Fine Structure of Platelet Interaction with a New Microcrystalline Collagen Preparation

1974 ◽  
Vol 32 ◽  
pp. 58-59
Author(s):  
W. H. Zucker ◽  
R. G. Mason
Keyword(s):  
Fine Structure ◽  
Platelet Aggregation ◽  
Hydrochloric Acid ◽  
Whole Blood ◽  
Platelet Adhesion ◽  
Hemostatic Agent ◽  
Native Collagen ◽  
Fibrillar Morphology ◽  
Clinical Interest ◽  
New Form

Platelet adhesion initiates platelet aggregation and is an important component of the hemostatic process. Since the development of a new form of collagen as a topical hemostatic agent is of both basic and clinical interest, an ultrastructural and hematologic study of the interaction of platelets with the microcrystalline collagen preparation was undertaken.In this study, whole blood anticoagulated with EDTA was used in order to inhibit aggregation and permit study of platelet adhesion to collagen as an isolated event. The microcrystalline collagen was prepared from bovine dermal corium; milling was with sharp blades. The preparation consists of partial hydrochloric acid amine collagen salts and retains much of the fibrillar morphology of native collagen.

Influence of Thermo-Mechanical Processing on the Microstructure of Beryllia Dispersed Nickel Alloys

1973 ◽  
Vol 31 ◽  
pp. 184-185
Author(s):  
M.S. Grewal ◽  
S.A. Sastri ◽  
N.J. Grant
Keyword(s):  
High Temperature ◽  
Nickel Alloys ◽  
Thermomechanical Processing ◽  
Cold Work ◽  
High Temperature Strength ◽  
Strengthening Effect ◽  
Mechanical Processing ◽  
Uniform Dispersion ◽  
Oxide Particles ◽  
Nickel Base

Currently there is a great interest in developing nickel base alloys with fine and uniform dispersion of stable oxide particles, for high temperature applications. It is well known that the high temperature strength and stability of an oxide dispersed alloy can be greatly improved by appropriate thermomechanical processing, but the mechanism of this strengthening effect is not well understood. This investigation was undertaken to study the dislocation substructures formed in beryllia dispersed nickel alloys as a function of cold work both with and without intermediate anneals. Two alloys, one Ni-lv/oBeo and other Ni-4.5Mo-30Co-2v/oBeo were investigated. The influence of the substructures produced by Thermo-Mechanical Processing (TMP) on the high temperature creep properties of these alloys was also evaluated.

Application of TEM to Deformation, Wear, and Fracture of Ceramics

1974 ◽  
Vol 32 ◽  
pp. 472-473
Author(s):  
B. J. Hockey
Keyword(s):  
Wear Resistance ◽  
High Temperature ◽  
Mechanical Behavior ◽  
Brittle Materials ◽  
High Temperature Strength ◽  
Wide Range ◽  
Corrosive Environments ◽  
Further Development

Ceramics, such as Al2O3 and SiC have numerous current and potential uses in applications where high temperature strength, hardness, and wear resistance are required often in corrosive environments. These materials are, however, highly anisotropic and brittle, so that their mechanical behavior is often unpredictable. The further development of these materials will require a better understanding of the basic mechanisms controlling deformation, wear, and fracture.The purpose of this talk is to describe applications of TEM to the study of the deformation, wear, and fracture of Al2O3. Similar studies are currently being conducted on SiC and the techniques involved should be applicable to a wide range of hard, brittle materials.

Lattice Imaging of Grain Boundaries in Ceramics

1977 ◽  
Vol 35 ◽  
pp. 114-115
Author(s):  
D. R. Clarke ◽  
G. Thomas
Keyword(s):  
Mechanical Properties ◽  
High Temperature ◽  
Silicon Nitride ◽  
Grain Boundaries ◽  
High Temperature Strength ◽  
Current Interest ◽  
Lattice Imaging ◽  
Special Significance ◽  
Structural Applications ◽  
Refractory Ceramics

Grain boundaries have long held a special significance to ceramicists. In part, this has been because it has been impossible until now to actually observe the boundaries themselves. Just as important, however, is the fact that the grain boundaries and their environs have a determing influence on both the mechanisms by which powder compaction occurs during fabrication, and on the overall mechanical properties of the material. One area where the grain boundary plays a particularly important role is in the high temperature strength of hot-pressed ceramics. This is a subject of current interest as extensive efforts are being made to develop ceramics, such as silicon nitride alloys, for high temperature structural applications. In this presentation we describe how the techniques of lattice fringe imaging have made it possible to study the grain boundaries in a number of refractory ceramics, and illustrate some of the findings.

Effect of Improved ThO2 Particle Dispersion in Nickel on High-Temperature Strength

1970 ◽  
Vol 28 ◽  
pp. 444-445
Author(s):  
E. R. Kimmel ◽  
H. L. Anthony ◽  
W. Scheithauer
Keyword(s):  
High Temperature ◽  
Metal Matrix ◽  
Oxide Particle ◽  
Oxide Phase ◽  
Dislocation Motion ◽  
Particle Dispersion ◽  
High Temperature Strength ◽  
Strengthening Effect ◽  
Oxide Particles ◽  
The Stability

The strengthening effect at high temperature produced by a dispersed oxide phase in a metal matrix is seemingly dependent on at least two major contributors: oxide particle size and spatial distribution, and stability of the worked microstructure. These two are strongly interrelated. The stability of the microstructure is produced by polygonization of the worked structure forming low angle cell boundaries which become anchored by the dispersed oxide particles. The effect of the particles on strength is therefore twofold, in that they stabilize the worked microstructure and also hinder dislocation motion during loading.

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