Initial stage of the C49-TiSi, formation was investigated at 530 “C and at a rate of 10 “C/m using transmission electron microscopy. Morphological studies reveal that the C49 phase first separately nucleates at the interface between amorphous silicide and crystalline silicon, then followed by simultaneous lateral and vertical growth. The growth proceeds very fast until the formation of a contin...

Microstructural study of the C49-TiSi, to C54-TiSi, polymorphic transformation has been performed to elucidate microstructural evolution and possible mechanism of the phase transformation. It has been shown that the nucleation of the C54-TiSi, is heterogeneous, and preferentially takes place at triple grain junctions or grain boundaries. The interphase interfaces between C49 and C54 disilicides...

Abstract Background Chronic renal failure is a common comorbidity in patients undergoing TAVI. Large amounts of contrast media are generally needed to safely perform TAVI with potential deleterious effects on function and long term life quality. Objectives Every step the procedure can be replaced by no techniques: ultrasound guided vascular puncture final check, alignement 3 guides Valsalva sin...

1010-7940/$ see front matter Q 2005 Elsevier B.V. All rights reserved. doi:10.1016/j.ejcts.2005.06.039 * Corresponding author. Tel.: C49 3641 9322901; fax: C49 3641 9322902. E-mail address: [email protected] (P.B. Rahmanian). paresis in both legs. MR surprisingly revealed a large intraspinal, but extramedullar tumor localized at Th 1–3 (Fig. 2). European Journal of Cardio-thoracic Su...

Evolution of the Ti/a-GelSi trilayer reactions has been investigated using transmission electron microscopy and Auger electron spectroscopy. Instead of amorphous phase formation, as usually observed in the Ti/Si bilayer reaction, the crystalline Ti,GeS is the first phase observed during the reaction. Preceding the equilibrium C5CTi(Si,Ge),, a substitutional solid solution type C49-Ti(Si,Ge), fo...

We demonstrate that picosecond ultrasonics is a sensitive nondestructive probe of the formation of TiSi, from the reaction of titanium films on silicon annealed at temperatures of 300-800 “C. From the measured change in optical reflectivity, the responses due to electronic excitation, acoustic echoes, and thermal coupling to the underlying Si are resolved. The results show significant differenc...

It has been demonstrated that C54 TiSi2 phase formation can be significantly enhanced by multi-thermal-shock (MTS) method. In this work, the enhancement mechanism of C54 phase formation and the interfacial reactions between TiSi2 and Si were investigated. The results indicate that the semi-coherent interface between TiSi2 C49 phase and Si substrate may be responsible for the rough surface of th...

In a recent paper [Phys. Rev. C49, 2142 (1994)], Haberzettl presented cluster N-body equations for arbitrarily large systems of nucleons and mesons. Application to the three-nucleon system is claimed to yield a new kind of three-nucleon force. We demonstrate that these three-nucleon equations contain double counting. 21.30.+y, 21.45+v, 21.60.-n, 21.60.Gx Typeset using REVTEX

We give new simple general expressions for the asymptotic covariance of the estimated system parameters (A,B,C,D) in subspace identification. The formulas can be applied to a whole class of subspace methods including N4SID, MOESP, CVA etc. The asymptotic expressions highlight how the conditioning of the estimation problem influences the accuracy of the estimates. Journal of Economic Literature ...