Coverage‐time dependence during island growth at a solid surface with application to diamond deposition from the gas phase

1992 ◽  
Vol 72 (4) ◽  
pp. 1589-1594 ◽  
Author(s):  
M. Tomellini
Keyword(s):  
Time Dependence ◽  
Gas Phase ◽  
Solid Surface ◽  
Island Growth ◽  
Diamond Deposition

Phase diagrams for CVD diamond deposition from halogen-containing gas phase

1999 ◽  
Vol 342 (1-2) ◽  
pp. 42-46 ◽  
Author(s):  
Zhi-Jie Liu ◽  
David Wei Zhang ◽  
Jian-Yun Zhang ◽  
Yong-Zhong Wan ◽  
Ji-Tao Wang
Keyword(s):  
Phase Diagrams ◽  
Gas Phase ◽  
Cvd Diamond ◽  
Diamond Deposition

THERMIONIC EMISSION FROM FULLERENES

1992 ◽  
Vol 06 (23n24) ◽  
pp. 3881-3891 ◽  
Author(s):  
Gerhard Walder ◽  
Olof Echt
Keyword(s):  
Time Dependence ◽  
Gas Phase ◽  
Mass Spectrometer ◽  
Rate Constants ◽  
Size Range ◽  
Thermionic Emission ◽  
Pulsed Laser ◽  
Yag Laser ◽  
Enhanced Sensitivity ◽  
Extraction Field

Fullerenes in the gas phase, excited by a pulsed laser, exhibit thermionic emission. We analyze the time dependence of the ion yield of C n + in a mass spectrometer. By pulsing the extraction field of the ion lens, we are able to observe delayed ions formed as late as 50 µs after excitation by the 2nd, 3rd or 4th harmonic of a Q-switched YAG laser. The enhanced sensitivity of this new technique allows us to detect delayed ions not only from excited C 60 and C 70, but from all other even-sized clusters in the size range 36≤ n ≤70. Our results do not confirm the assertion that thermionic emission from C 60 and C 70 can be characterized by just 2 or 3 distinct rate constants.

Contact angles and hysteresis, with some reference to flotation research

1977 ◽  
Vol 30 (1) ◽  
pp. 205 ◽  
Author(s):  
IW Wark
Keyword(s):  
Surface Roughness ◽  
Contact Angle ◽  
Gas Phase ◽  
Water Vapour ◽  
Relative Motion ◽  
Solid Surface ◽  
Contact Angles ◽  
Russian School ◽  
Angle Measurements ◽  
Contact Angle Measurements

A technique used in flotation research for contact angle measurements is recommended for wider use. The effect of one aspect of surface roughness on the relative motion of fluid/solid systems is discussed. The function of the water vapour present in the gas phase adjacent to the line of triple contact is examined. A claim of the Russian school of surface chemists is questioned, namely, that a discrete film of water on the solid surface invariably dominates both hysteresis and contact angle.

scholarly journals The interaction of vapour molecules with a crystal surface

1937 ◽  
Vol 161 (904) ◽  
pp. 68-79 ◽  
Keyword(s):  
Gas Phase ◽  
Solid Surface ◽  
Crystal Surface ◽  
Crystal Surfaces ◽  
Early Evidence ◽  
Gas Molecules ◽  
Special Case ◽  
Vapour Molecule

When a gas or vapour molecule strikes a solid surface it may either condense on the surface and remain there for some time before returning to the gas phase, or it may rebound at once from the surface. The ratio of the number of molecules condensing on any surface per second to the total number incident on that surface per second may be defined as the “coefficient of condensation” f . The value of this coefficient will be expected to vary with the nature of the solid surface and of the gas but in a number of cases (Langmuir 1916) early evidence indicated that it is close to unity and it has sometimes been assumed that this is always so. The experiments described in the present paper were designed to test the correctness of this assumption, and for this purpose the coefficient of condensation has been measured at a number of crystal surfaces. The measurement can be made very directly in the special case in which the solid and the gas molecules are identical in nature, and for this reason crystals which sublime at ordinary temperatures have been used and f has been measured for the collisions of the vapour molecules with a solid surface of the same substance.

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