Effect of surface porosity on ceramics during Al2O3/Ti bonding through brazing

Until recently the prime purposes of filters have been to produce clear filtrates or to collect particles from solution and then remove the filter medium and examine the particles by transmission electron microscopy. These filters have not had the best characteristics for scanning electron microscopy due to the size of the pores or the surface topography. Advances in polymer chemistry and membrane technology resulted in membranes whose characteristics make them versatile substrates for many scanning electron microscope applications. These polysulphone type membranes are anisotropic, consisting of a very thin (0.1 to 1.5 μm) dense skin of extremely fine, controlled pore texture upon a much thicker (50 to 250μm), spongy layer of the same polymer. Apparent pore diameters can be controlled in the range of 10 to 40 A. The high flow ultrafilters which we are describing have a surface porosity in the range of 15 to 25 angstrom units (0.0015-0.0025μm).

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Nucleation and initial growth of Pd2Si crystals on Si(111)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100150058 ◽

1993 ◽

Vol 51 ◽

pp. 844-845

Author(s):

Xianghong Tong ◽

Oliver Pohland ◽

J. Murray Gibson

Keyword(s):

High Vacuum ◽

Dark Field ◽

Ultra High Vacuum ◽

Initial Growth ◽

Surface And Interface ◽

Dark Field Imaging ◽

Transmission Electron ◽

Initial Stage ◽

Effect Of Surface

The nucleation and initial stage of Pd2Si crystals on Si(111) surface is studied in situ using an Ultra-High Vacuum (UHV) Transmission Electron Microscope (TEM). A modified JEOL 200CX TEM is used for the study. The Si(111) sample is prepared by chemical thinning and is cleaned inside the UHV chamber with base pressure of 1x10−9 τ. A Pd film of 20 Å thick is deposited on to the Si(111) sample in situ using a built-in mini evaporator. This room temperature deposited Pd film is thermally annealed subsequently to form Pd2Si crystals. Surface sensitive dark field imaging is used for the study to reveal the effect of surface and interface steps.The initial growth of the Pd2Si has three stages: nucleation, growth of the nuclei and coalescence of the nuclei. Our experiments shows that the nucleation of the Pd2Si crystal occurs randomly and almost instantaneously on the terraces upon thermal annealing or electron irradiation.

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Review for "Combined effect of both surface finish and sub‐surface porosity on component strength under repeated load conditions"

10.1002/eng2.12248/v1/review3 ◽

2020 ◽

Author(s):

Romali Biswal

Keyword(s):

Surface Finish ◽

Combined Effect ◽

Surface Porosity ◽

Component Strength ◽

Repeated Load ◽

Load Conditions

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EFFECT OF SURFACE CONDITIONS ON COERCIVITIES FOR Nd-Fe-B MAGNETS

Le Journal de Physique Colloques ◽

10.1051/jphyscol:19888290 ◽

1988 ◽

Vol 49 (C8) ◽

pp. C8-641-C8-642

Author(s):

Y. Otani ◽

H. Miyajima ◽

S. Chikazumi ◽

S. Hirosawa ◽

M. Sagawa

Keyword(s):

Surface Conditions ◽

Effect Of Surface

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A Modified Thromboplastin Screening Test

Thrombosis and Haemostasis ◽

10.1055/s-0038-1654580 ◽

1961 ◽

Vol 06 (03) ◽

pp. 492-497 ◽

Cited By ~ 2

Author(s):

Janet C. Macpherson ◽

R. M Hardisty

Keyword(s):

Standard Method ◽

Comparative Studies ◽

Screening Test ◽

Incubation Mixture ◽

Surface Contact ◽

Modified Test ◽

Effect Of Surface

SummaryA modification of the thromboplastin screening test of Hicks and Pitney is described, in which the effect of surface contact on the test plasma is controlled by the addition of a suspension of kaolin to the incubation mixture before recalcification.Comparative studies show the modified test to give more reproducible results than the standard method.

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