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111.
R. A. J. Janssen D. Moses N. S. Sariciftci A. J. Heeger 《Molecular Crystals and Liquid Crystals》2013,570(1):921-926
Abstract Photoexcitation of a nonathiophene in film or solution across the π-π* energy gap produces a metastable triplet state. In the presence of C60, on the other hand, an ultra fast electron transfer from the photoexcited nonathiophene onto C60 is observed in films, whereas in solution C60 is involved in an efficient energy transfer reaction with the triplet-state nonathiophene. 相似文献
112.
Elisabeth W. Leib Robert M. Pasquarelli Malte Blankenburg Martin Müller Andreas Schreyer Rolf Janssen Horst Weller Tobias Vossmeyer 《Particle & Particle Systems Characterization》2016,33(9):645-655
Zirconia microspheres synthesized by a wet‐chemical sol–gel process are promising building blocks for various photonic applications considered for heat management and energy systems, including highly efficient reflective thermal barrier coatings and absorbers/emitters used in thermophotovoltaic systems. As previously shown, pure zirconia microparticles deteriorate at working temperatures of ≥1000 °C. While the addition of yttrium as a dopant has been shown to improve their phase stability, pronounced grain growth at temperatures of ≥1000 °C compromises the photonic structure of the assembled microspheres. Here, a new approach for the fabrication of highly stable ceramic microparticles by doping with lanthanum, gadolinium, and a combination of those with yttrium is introduced. The morphological changes of the particles are monitored by scanning electron microscopy, ex situ X‐ray diffraction (XRD), and in situ high‐energy XRD as a function of dopant concentration up to 1500 °C. While the addition of lanthanum or gadolinium has a strong grain growth attenuating effect, it alone is insufficient to avoid a destructive tetragonal‐to‐monoclinic phase transformation occurring after heating to >850 °C. However, combining lanthanum or gadolinium with yttrium leads to particles with both efficient phase stabilization and attenuated grain growth. Thus, ceramic microspheres are yielded that remain extremely stable after heating to 1200 °C. 相似文献
113.
Littrow Steinheil W. Gibbs M. Janssen Valentiner und R. Simmler 《Fresenius' Journal of Analytical Chemistry》1863,2(1):190-192
Ohne Zusammenfassung 相似文献
114.
115.
H. Nissenson und R. L. Janssen 《Fresenius' Journal of Analytical Chemistry》1923,62(1-2):63-64
Ohne Zusammenfassung 相似文献
116.
117.
Summary Nowadays SIMS is a well-established analytical technique in semiconductor research. Materials research and process development are the main fields of application in silicon technology, whereas for III–V compound semiconductors much attention has been paid to assessment of multilayer structures grown by advanced growth methods. Recent applications of SIMS in these fields are the subject of the present paper. Emphasis will be placed upon optimizing the SIMS results with respect to accuracy and depth resolution.
Anwendungen von SIMS in der Halbleiterforschung相似文献
118.
M.A.J. van Gils O. van der Sluis G.Q. Zhang J.H.J. Janssen R.M.J. Voncken 《Microelectronics Reliability》2007,47(2-3):179-186
For the development of state-of-the-art Cu/low-k CMOS technologies, the integration and introduction of new low-k materials is one of the major bottlenecks owing to the bad thermal and mechanical integrity of these materials and the inherited weak interfacial adhesion. Especially the forces resulting from packaging related processes such as dicing, wire bonding, bumping and molding are critical and can easily result in cracking, delamination and chipping of the IC back-end structure if no appropriate measures are taken. This paper presents a methodology for optimizing the thermo-mechanical reliability of bond pads by using a 3D multi-scale finite element approach. An important characteristic of this methodology is the use of a novel energy-based failure index, which allows a fast qualitative comparison of different back-end structures. The usability of the methodology will be illustrated by a case study in which several bond pad structures are analysed. 相似文献
119.
Janssen A.J.E.M. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》1996,42(2):621-623
We present an example of a positive function g with a positive Fourier transform gˆ and reasonable smoothness and decay properties such that (-1)nmexp(πitm)g(t-n), n, m∈Z does not constitute a frame for L2(R ). We also give counterexamples for the statement that one can tell (in)definiteness of a Weyl-Heisenberg frame operator from (in)definiteness of its Weyl symbol 相似文献
120.
Cassandra L Schlamp Yan Li Joel A Dietz Katherine T Janssen Robert W Nickells 《BMC neuroscience》2006,7(1):66-14