Detailed mechanism of the unsteady combustion around hypersonic projectiles

AIAA Journal ◽  
1996 ◽  
Vol 34 (10) ◽  
pp. 2082-2089 ◽  
Author(s):  
Akiko Matsuo ◽  
Kozo Fujii
Author(s):  
C. Vannuffel ◽  
C. Schiller ◽  
J. P. Chevalier

Recently, interest has focused on the epitaxy of GaAs on Si as a promising material for electronic applications, potentially for integration of optoelectronic devices on silicon wafers. The essential problem concerns the 4% misfit between the two materials, and this must be accommodated by a network of interfacial dislocations with the lowest number of threading dislocations. It is thus important to understand the detailed mechanism of the formation of this network, in order to eventually reduce the dislocation density at the top of the layers.MOVPE growth is carried out on slightly misoriented, (3.5°) from (001) towards , Si substrates. Here we report on the effect of this misorientation on the interfacial defects, at a very early stage of growth. Only the first stage, of the well-known two step growth process, is thus considered. Previously, we showed that full substrate coverage occured for GaAs thicknesses of 5 nm in contrast to MBE growth, where substantially greater thicknesses are required.


1975 ◽  
Vol 142 (2) ◽  
pp. 312-320 ◽  
Author(s):  
G S Habicht ◽  
J M Chiller ◽  
W O Weigle

It was possible to terminate the induced unresponsive state to bovine serum albumin (BSA) and the natural unresponsive state to autologous thyroglobulin in rabbits (RTg) by immunization with complexes composed of heterologous cross-reacting antibody and the tolerated antigens. The unresponsive state was terminated in rabbits made unresponsive by neonatal injections of BSA and then 3 mo later injected with complexes composed of BSA and guinea pig antihuman serum albumin. This termination was manifested by the presence of anti-BSA plaque-forming cells. Similarly, the natural unresponsive state was terminated in adult rabbits injected with complexes between RTg and guinea pig antibovine thyroglobulin (BTg) in that thyroid lesions and circulating anti-RTg were produced. The results can be best explained by the presence of unresponsive T cells and competent B cells, where the guinea pig gamma globulin (antibody) activates T cells specific for the guinea pig gamma globulin portion of the complexes and thus permits stimulation of B cells competent to the exposed determinants of the tolerated (BSA or RTg) portion of the complexes. The detailed mechanism for the activation of B cells in tolerant animals is discussed.


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